A

adhesive, n
A material which is adhesive resistant and applicable as a non-sticking surface coating; release agent.

abrasion resistance, n
Ability of a tape to withstand rubbing and still function satisfactorily.

accelerated aging, n
A set of laboratory conditions designed to produce in a short time the results of normal aging (usual factors include temperature, light, oxygen, water, and other environments as needed).

accelerator, n
An ingredient used in small amounts to speed up the action of a curing agent (sometimes used as a synonym for curing agent).
Related Words  curing agent, n

acceptance test, n
A test, or series of tests conducted by the procuring agency, or an agent thereof, upon receipt to determine whether an individual lot of materials conforms to the purchase order or contract or to determine the degree of uniformity of the material supplied by the vendor, or both. (Compare preproduction test and qualification test.) (ASTM D 907-06)
Related Words  preproduction test, n; qualification test, n

acetate (cellulose acetate), n
A transparent film which is used for various reasons in tape backings; the primary characteristic is that of being more moisture resistant than cellophane.

acrylic, adj, n
A synthetic polymer with excellent aging characteristics that can be used as either a single component adhesive, coating or saturant, depending upon composition.

activator, n
A material that speeds up normal curing mechanisms.

adhere, v
To cause two surfaces to be held together by adhesion. (ASTM D 907-06)

adherend, n
A body held to another body by an adhesive. adherend preparation, n—see surface preparation. (ASTM D 907-06)
Related Words  surface preparation, n

adhesion (adhesive) failure, n
Rupture of an adhesive bond in which the separation appears visually to be at the adhesive/adherend interface. (ASTM D 907-06); in building construction, failure of the bond between the sealant, adhesive, or coating and the substrate surface. (ASTM C 717-07a); in pressure sensitive tapes, when performing a loop tack test, after the initial touch of the coated stock to the stainless steel plate, all of the adhesive remains on the coated stock. Compare cohesion failure.
Related Words  cohesion (cohesive) failure, n

adhesion build-up, n
An increase in the peel adhesion value of a pressure-sensitive tape after it has been allowed to dwell on the applied surface.

adhesion promoter, n
A substance used to improve bonding of the adhesive to the substrate. (Compare coupling agent and primer.) Discussion—The adhesion promoter may be added to an adhesive formulation or applied to the substrate. (ASTM D 907-06)
Related Words  coupling agent, n; primer, n

adhesion to backing, n
The bond produced by contact between a pressure-sensitive adhesive and the tape backing when one piece is applied to the back of another piece of the same tape.

adhesion, n
The state in which two surfaces are held together by interphase forces; mechanical adhesion, n—adhesion between surfaces in which the adhesive holds the parts together by interlocking action; specific adhesion, n—adhesion between surfaces which are held together by intermolecular forces of a chemical or physical nature. (ASTM D 907-06)

adhesive n
A substance capable of holding materials together by surface attachment. (See also glue, gum, mucilage, paste, resin, and sizing.) Discussion—Adhesive is the general term and includes among others cement, glue, mucilage, and paste. These terms are loosely used interchangeably. Various descriptive adjectives are applied to the term adhesive to indicate certain characteristics as follows: (1) Physical form, that is, liquid adhesive, tape adhesive; (2) Chemical type, that is, silicate adhesive, resin adhesive; (3) Materials bonded, that is, paper adhesive, metal-plastic adhesive; (4) Conditions of use, that is, hot-setting adhesive. (ASTM D 907-06)
Related Words  cement, n; glue (archaic), n; gum, n; mucilage, n; paste, n; resin, n; sizing, n

adhesive deposit, n
A pressure-sensitive adhesive which is pulled away from the tape and remains on the surface to which the tape was applied.

adhesive dispersion, n
A two-phase system in which one phase is suspended in a liquid. (Compare to emulsion.) (ASTM D 907-06)
Related Words  emulsion, n

adhesive joint, n
The location at which two adherends are held together with adhesive. (ASTM D 907-06)

adhesive transfer, n
The transfer of adhesive from its normal position on the tape to the surface to which the tape was attached, either during unwind or removal.

adhesive, anaerobic, n
See anaerobic adhesive.
Related Words  anaerobic adhesive, n

adhesive, assembly, n
See assembly adhesive.
Related Words  assembly adhesive, n

adhesive, bulk, n
See bulk adhesive.
Related Words  bulk adhesive, n

adhesive, casein, n
See casein adhesive.
Related Words  casein adhesive, n

adhesive, cellular, n
See cellular adhesive.
Related Words  cellular adhesive

adhesive, cold-setting, n
See cold-setting adhesive.
Related Words  cold-setting adhesive, n

adhesive, contact, n
See contact adhesive.
Related Words  contact adhesive, n

adhesive, encapsulated, n
See encapsulated adhesive.
Related Words  encapsulated adhesive, n

adhesive, film, n
See film adhesive.
Related Words  film adhesive, n

adhesive, foamed, n
See foamed adhesive.
Related Words  foamed adhesive, n

adhesive, gap-filling, n
See gap-filling adhesive.
Related Words  gap-filling adhesive, n

adhesive, heat activated, n
See heat activated adhesive.
Related Words  heat activated adhesive, n

adhesive, hot-melt, n
See hot-melt adhesive.
Related Words  hot-melt adhesive, n

adhesive, hot-setting, n
See hot-setting adhesive.
Related Words  hot-setting adhesive, n

adhesive, intermediate-temperature-setting, n
See intermediate-temperature-setting adhesive.
Related Words  intermediate-temperature-setting adhesive, n

adhesive, mastic, n
See mastic adhesive.
Related Words  mastic adhesive, n

adhesive, multiple-layer, n
See multiple-layer adhesive.
Related Words  multiple-layer adhesive, n

adhesive, polyvinyl acetate emulsion, n
See polyvinyl acetate emulsion adhesive.
Related Words  polyvinyl acetate emulsion adhesive, n

adhesive, pressure-sensitive, n
See pressure-sensitive adhesive.
Related Words  pressure-sensitive adhesive (PSA), n

adhesive, room-temperature-setting, n
See room-temperature-setting adhesive.
Related Words  room-temperature-setting adhesive, n

adhesive, separate application, n
See separate-application adhesive.
Related Words  separate-application adhesive, n

adhesive, silicone, n
See silicone adhesive.
Related Words  silicone adhesive, n

adhesive, solvent, n
See solvent adhesive.
Related Words  solvent adhesive, n

adhesive, solvent-activated, n
See solvent-activated adhesive.
Related Words  solvent-activated adhesive, n

adhesive, structural, n
See structural adhesive.
Related Words  structural adhesive, n

adhesive, thermoplastic, n
See thermoplastic adhesive under thermoplastic.
Related Words  thermoplastic, n, adj

adhesive, thermosetting, n
See thermosetting adhesive under thermoset.
Related Words  thermoset, n, adj

adhesive, two-component, n
See two-component adhesive.
Related Words  two-component adhesive, n

adhesive, urea-formaldehyde, n
See urea-formaldehyde adhesive.
Related Words  urea-formaldehyde adhesive, n

adhesive, UV-curing, n
See UV curing adhesive under ultraviolet light.
Related Words  ultraviolet light (UV), n

adhesive, warm-setting, n
See warm-setting adhesive.
Related Words  warm-setting adhesive, n

adhesive-joint failure, n
The locus of fracture occurring in an adhesively-bonded joint resulting in a loss of load-carrying capability. (ASTM D 907-06)

adsorption, n
The action of a body in condensing and holding gases and other materials at its surface.

aging, aging time, n
See joint conditioning time.
Related Words  joint conditioning time

alligatoring, n
Cracking of a surface into segments so that it resembles the hide of an alligator.

ambient temperature, n
Temperature of the air surrounding the object under construction or test.

amylaceous, adj
Pertaining to, or of the nature of, starch; starchy. (ASTM D 907-06)

anaerobic adhesive, n
An adhesive that is kept in the uncured state by oxygen, as in air, and that cures in the absence of oxygen when exposed to metal ions, especially copper or iron. (ASTM D 907-06)

apparent viscosity, n
In non-Newtonian behavior, the ratio of the shearing stress to the rate of shear of a fluid, given at the corresponding shearing stress. (ASTM D 907-06)

asphalt, n
A naturally occurring mineral pitch or bitumen.

assembly (for adhesives), n
A group of materials or parts, including adhesive, placed together for bonding or which has been bonded together. (ASTM D 907-06)

assembly adhesive, n
An adhesive that can be used for bonding parts together, such as in the manufacture of a boat, airplane, furniture, and the like. Discussion—The term assembly adhesive is commonly used in the wood industry to distinguish such adhesives (formerly called joint glues) from those used in making plywood (sometimes called veneer glues). It is applied to adhesives used in fabricating finished structures or goods, or subassemblies thereof, as differentiated from adhesives used in the production of sheet materials for sale as such, for example, plywood or laminates. (ASTM D 907-06)

assembly time, n
The time interval between applying the adhesive on the substrate and the application of pressure, or heat, or both, to the assembly. Discussion—For assemblies involving multiple layers or parts, the assembly begins with applying the adhesive on the first substrate.
closed assembly time, n – time interval between the closing together of substrates after the adhesive has been applied, and the application of pressure, heat, or both, to the assembly.
open assembly time, n – time interval between applying adhesive on the substrates and closing them together before bonding. (ASTM D 907-06)
Related Words  closed assembly time, n; open assembly time, n

assembly, n
See adhesive, assembly.
Related Words  adhesive, assembly, n

A-stage, n
An early stage in the preparation of certain thermosetting resins, in which the material is still soluble in certain liquids, and fusible. (ASTM D 907-06)

 

B

back bedding, n
See bedding.
Related Words  bedding, n

back putty, n
See bedding.
Related Words  bedding, n

backing, n
In pressure-sensitive tapes, a relatively thin flexible supporting material to which an adhesive is applied. Pressure sensitive adhesives are commonly backed with paper, plastic films, fabric, or metal foil while heat curing thermosetting adhesives are often supported on glass cloth backing.

back-up material, n
See sealant backing.
Related Words  sealant backing

bag molding, n
A method of molding or bonding involving the application of fluid pressure, usually by means of air, steam, water, or vacuum, to a flexible cover which, sometimes in conjunction with the rigid die, completely encloses the material to be bonded. (ASTM D 907-06)

band aid sealant joint, n
Use bridge sealant joint (preferred term). (ASTM C717-07a)
Related Words  bridge sealant joint, n

batch, n
The manufactured unit or a blend of two or more units of the same formulation and processing. (Compare manufactured unit.) (ASTM D 907-06)
Related Words  manufactured unit, n

batten plate, n
A thin metal plate separated by sealant beads to bridge poorly designed joints.

bead, n
In building construction, in sealants and glazing, a strip of applied sealant, glazing compound, or putty. (ASTM C717-07a)

bed, n
See bedding.
Related Words  bedding, n

bed, v
In building construction in glazing, to apply a bead of sealant between a lite of glass or a panel and the stationary stops or sight bars of the sash or frame. (ASTM C717-07a)

bedding, n
In building construction in glazing, a bead of sealant applied between a lite of glass or a panel and the stationary stop or sight bar of the sash or frame. It is usually the first bead to be applied when setting glass or panels. (ASTM C717-07a)

bicellular sealant backing, n
A flexible and very compressible extruded shape (usually cylindrical), with a surface skin, that is composed of both open and closed cell material. (ASTM C717-07a)

bi-directional, adj
Related to strapping tapes, in which the reinforcing material consists of filaments in both strength and cross directions, usually a woven cloth.

binder, n
In adhesive compounds , a component of an adhesive composition that is primarily responsible for its mechanical strength and adhesion. (ASTM D 907-06)

birefringence, n
The refraction of light in two slightly different directions to form two rays; the phenomenon can be used to locate stress in a transparent material.

bite, n
In building construction in glazing, the effective structural contact dimension of a structural sealant. (ASTM C717-07a)
Click here for figure.

bleaching, n
An erroneous term used to denote a corrosion of the surface under a tape which has remained the original surface color while the surround­ing surface area has discolored.

bleeding, n
Penetration through the tape of a coloring liquid (paint, etc.) onto the surface to which the tape is applied.

blister, n
An elevation of the surface of varied contour and dimensions, with a void beneath it. (ASTM D 907-06) Discussion—a blister may be caused by: insufficient adhesive; inadequate curing time, temperature, or pressure; trapped air, water, or solvent vapor.

blocked curing-agent, n
A curing or hardening agent temporarily rendered unreactive, which can be reactivated as desired by physical or chemical means. (ASTM D 907-06)

blocking, n
An undesired adhesion between touching layers of a material, such as occurs under moderate pressure during storage or use. (ASTM D 907-06)

bloom, n
In building construction, a substance formed by blooming. (ASTM C717-07a)

blooming, v
In building construction, movement or diffusion of a component such as a plasticizer, monomer, unreacted polymer or other formulation ingredient to a sealant surface. (ASTM C717-07a)

bond breaker, n
In building construction, a material to prevent adhesion at a designated interface. (ASTM C717-07a)

bond durability, n
Test cycle, as described in ASTM C-920, for measuring the bond strength after repeated weather and extension cycling.

bond strength, n
The unit load applied to tension, compression, flexure, peel, impact, cleavage, or shear, required to break an adhesive assembly with failure occurring in or near the plane of the bond. (See also adhesion and bond.) Discussion— The term adherence is frequently used in place of bond strength.
dry strength, n—the strength of an adhesive joint determined immediately after drying under specified conditions or after a period of conditioning in a standard laboratory atmosphere.
wet strength, n—the strength of an adhesive joint determined immediately after removal from a liquid in which it has been immersed under specified conditions of time, temperature, and pressure. Discussion—The term is commonly used alone to designate strength after immersion in water. In latex adhesives the term is also used to describe the joint strength when the adherends are brought together with the adhesive still in the wet state. (ASTM D 907-06)
Related Words  adhesion, n; bond, n

bond, n
The attachment between an adhesive and an adherend.
edge joint, n—in wood bonding, a type of laminate joint made by bonding adherends edge-to-edge with grain directions parallel to form wider stock.
face joint, n—in wood bonding, a type of laminate joint made by bonding adherends face-to-face with grain directions parallel to form thicker stock.
laminate joint, n—in wood bonding, a joint made by bonding layers of adherends face-to-face or edge-to-edge to form thicker or wider stock. (ASTM D 907-06)

bond, v
To join adherends by means of an adhesive. (ASTM D 907-06)

bondline, n
The layer of adhesive which attaches two adherends. (See interphase.) (ASTM D 907-06)

bridge sealant joint, n
In building construction, a joint where sealant is applied over the joint to the face of substrates that are in approximately the same plane.  Discussion—Not to be confused with joints in bridges. (ASTM C717-07a)
Click here for figure.

B-stage, n
An intermediate stage in the reaction of certain thermosetting resins in which the material swells when in contact with certain liquids and softens when heated, but may not entirely dissolve or fuse. (ASTM D 907-06)

building seal, n
See seal.
Related Words  seal, n

built-up laminated wood, n
See built-up laminated wood under wood laminates.
Related Words  wood laminates, n

bulk adherend, n
As related to interphase, the adherend, unaltered by the adhesive. (Compare to bulk adhesive.) (ASTM D 907-06)
Related Words  bulk adhesive, n

bulk adhesive, n
As related to interphase, the adhesive, unaltered by the adherend. (Compare to bulk adherend.) (ASTM D 907-06)
Related Words  bulk adherend, n

bulk compounds, n
Any sealant or caulk that has no defined shape and is stored in a container.

bursting strength, n
The ability of a tape to resist damage when force is evenly applied perpendicularly to the surface of the tape.

butt glazing, n
In building construction, a glazing system wherein butt joints are formed between lites and filled with a glazing sealant. (ASTM C717-07a)

butt joint, n
See butt sealant joint.
Related Words  butt sealant joint, n

butt sealant joint, n
In building construction, a joint where sealant is applied within the joint between approximately parallel substrate surfaces that are face-to-edge or edge-to-edge. (ASTM C717-07a)
Click here for figure.

 

C

cap bead, n
A bead placed above a gasket in a glazing design.

carbon black, n
Finely divided carbon used as a reinforcing filler in sealants.

carrier, n
Sometimes used to refer to the backing material, particularly in double-faced tapes.

casein adhesive, n
An aqueous colloidal dispersion of casein that may be prepared with or without heat, may contain modifiers, inhibitors, and secondary binders to provide specific adhesive properties, and includes a subclass, usually identified as casein glue, that is based on a dry blend of casein, lime, and sodium salts, mixed with water and prepared without heat. (ASTM D 907-06)

catalyst, n
A substance that initiates or changes the rate of chemical reaction, but is not consumed or changed by the reaction. (See also hardener.) (Compare inhibitor.) (ASTM D 907-06)
Related Words  hardener, n; inhibitor, n

caul, n
A sheet of material employed singly or in pairs in hot or cold pressing of assemblies being bonded.
Discussion—A caul is used to protect either the faces of the assembly or the press platens, or both, against marring and staining to prevent sticking; to facilitate press loading; to impart a desired surface texture or finish; and to provide uniform pressure distribution.
Discussion—A caul may be made of any suitable material such as aluminum, stainless steel, hardboard, fiberboard, or plastic; the length and width dimensions being generally the same as those of the plates of the press where it is used. (ASTM D 907-06)

caulk, n
See sealant.
Related Words  sealant (n)

caulk, v
In building construction, to install or apply a sealant across or into a joint, crack, or crevice.

caulking compound, n
See sealant.
Related Words  sealant (n)

caulking, n
See sealant.
Related Words  sealant (n)

cell, n
A single small cavity surrounded partially or completely by walls. (ASTM C 717-07a)

cellophane (regenerated cellulose), n
A thin trans­parent film manufactured from wood pulp.

cellular adhesive
See foamed adhesive.
Related Words  foamed adhesive, n

cellular material, n
A generic term for materials containing many cells (either open, closed, or both) dispersed through the mass. (ASTM C717-07a)

cement, n
See Discussion under adhesive.
Related Words  adhesive (n)

cement, v
See bond, v.
Related Words  bond, v

chain stopper, n
A material added during the polymerization process to terminate or control the degree of the reaction. This could result in soft sealants, or higher elongation.

chalk, n
In building construction, a powder formed by chalking. Discussion—The powder is not necessarily white. (ASTM C717-07a)

chalking, v
In building construction, formation of a powder on the surface of a sealant that is caused by the disintegration of the polymer or binding medium due to weathering. Discussion—Chalk on a light color sealant is often white, however a darker color can also exhibit chalking. (ASTM C717-07a)

channel glazing, n
The method of glazing in which lites are set in a channel formed by two stops (ASTM C717-07a)
Click here for figure.

chemical cure, n
Curing by a chemical reaction. Usually involves the cross-linking of a polymer.

cleavage strength, n
The force per unit width of bond line required to produce progressive separation by wedge or other crack-opening type action of two adherends. (ASTM D 907-06)

cleavage, n
In an adhesively bonded joint, a separation in the joint caused by wedge or other crack-opening type action. (ASTM D 907-06)

cleavage-peel strength, n
The force per unit width of bondline required to produce progressive separation by wedge or other crack-opening type action of two adherends where one or both undergo significant bending. (ASTM D 907-06)

closed assembly time, n
The time between the assembling of adhesive-coated surfaces and the application of heat or pressure, or both, to set the adhesive. (ASTM D 907-06)

closed cell material, n
A cellular material in which substantially all cells in the mass are closed cells. (ASTM C 717-07a)

closed cell sealant backing, n
In building construction, a flexible and somewhat compressible extruded shape (usually cylindrical), with a surface skin, that is composed of closed cell material. (ASTM C717-07a)

closed cell, n
A cell totally enclosed by its walls and hence not interconnecting with other cells. (ASTM C717-07a)

coated cloth, n
Fabric with a rubber or plastic back coating to give increased moisture resistance and longer wear.

cohesion (cohesive) failure, n
Rupture of a bonded assembly in which the separation appears visually to be in the adhesive or the adherend. (ASTM D 907-06); in building construction, failure characterized by rupture within the sealant, adhesive, or coating. (ASTM C 717-07a); in pressure sensitive tapes, when the adhesive is left on both the substrate that it was coated to and the substrate that it comes into contact with, after it is removed from that substrate. For example, when performing a loop tack, after the initial touch of the coated stock to the stainless steel plate, the adhesive is left on both the coated stock and the stainless steel plate. See adhesion (adhesive) failure, n.
Related Words  adhesion (adhesive) failure, n

cohesion, n
The state in which the constituents of a mass of material are held together by chemical and physical forces. (ASTM D 907-06); the ability of the adhesive or sealant to resist splitting.

cohesive blocking, n
See blocking.
Related Words  blocking, n

cold flow
See creep.
Related Words  creep, n

cold pressing, n
A bonding operation in which an assembly is subjected to pressure without the application of heat. (ASTM D 907-06)

cold-setting adhesive, n
An adhesive that sets without the application of heat. (ASTM D 907-06)

colophony, n
See rosin.
Related Words  rosin, n

color stability, n
The ability of a tape to retain its original color, particularly when exposed to light.

color, n
The particular color of a tape, when looking at the backing, regardless of the color of the adhesive.

compatibility, n
In building construction, the capability of two or more materials to be placed in contact or close proximity with no detrimental interaction. Discussion—Compatibility for a sealant is characterized by, among others, no significant change in adhesive and cohesive properties or aesthetic appearance for its service life. (ASTM C717-07a)

compatible materials, n
In building construction, compounds or substances that can exist in close proximity to one another without detrimental effects on either. (ASTM C717-07a)

compression seal, n
A seal which is attained by a compressive force on the sealing material. (ASTM C717-07a)

condensation, n
A chemical reaction in which two or more molecules combine with the separation of water or some other simple substance. (See also polymerization.) Discussion—The process is called polycondensation if a polymer is formed. (ASTM D 907-06)

conditioning time, n
See joint conditioning time. (See also curing time and setting time.)
Related Words  cure, curing time, n; joint conditioning time; setting time, n

cone penetrometer, n
An instrument for measuring the relative hardness of soft deformable materials.

conformability, n
The ability of tape to fit snugly or make essentially complete contact with the surface of an irregular object without creasing or folding.

consistency, n
That property of a liquid adhesive by virtue of which it tends to resist deformation. (See also viscosity and viscosity coefficient.) Discussion—Consistency is not a fundamental property but is comprised of viscosity, plasticity, and other phenomena. (ASTM D 907-06)
Related Words  viscosity coefficient, n; viscosity, n

contact adhesive, n
Adhesive that is applied to both adherends and after a specified open assembly time will instantly develop a bond when a firm but not sustained pressure is applied. (ASTM D 907-06)

contact bond adhesive, n
Synonym for contact adhesive.
Related Words  contact adhesive, n

copolymer, n
See polymer.
Related Words  polymer, n

copolymerization, n
See polymerization.
Related Words  polymerization, n

corrosion, n
The chemical reaction between the adhesive or contamination and the adherend surfaces, due to reactive compounds in the adhesive film, leading to deterioration of the bond strength.

coupling agent, n
A substance having functional groups that are capable of reacting with the surfaces of two different substances, thereby chemically bridging them. (ASTM D 907-06)

coverage, n
The spreading power of an adhesive over the surface area of the adherend.

crazing, n
A fracture at or under the surface. (ASTM D 907-06)

creep strain, n
The total strain, at any given time, produced by the applied stress during a creep test. (ASTM D 907-06)

creep, n
In an adhesive, the time-dependent deformation usually resulting from sustained stress (sometimes called cold flow). (ASTM D 907-06); Discussion—phenomena as oozing and increases in adhesion often result from this characteristic.

creped, adj
In pressure-sensitive tapes, paper or some other material which has small “folds” in it, giving it high stretch.

cross laminate, n
See cross laminate under laminate , n.
Related Words  laminate, n

crosslink, v
To form chemical bonds between molecules to produce a three-dimensional network. (ASTM D 907-06) Discussion—An improvement in shear resistance, high temperature resistance, and oil or solvent resis­tance will normally result.

C-stage, n
The final stage in the reaction of thermosetting resins, in which the material is practically insoluble and infusible. (ASTM D 907-06)

cupping, n
In pressure sensitive tapes, a slightly U-shaped deformation of the tape (at right angles to the length) which usually appears after unwind tension is relaxed.

cure, curing time, n
The period of time during which an assembly is subjected to heat or pressure, or both, to cure the adhesive. (See also joint-conditioning time, setting time.) Discussion – further cure may take place after removal of the assembly from the conditions of heat or pressure, or both. (ASTM D 907-06)

cure, n
The process by which a compound attains its intended performance properties by means of evaporation, chemical reaction, heat, radiation, or combinations thereof. (ASTM C717-07a)

cure, v
To develop the strength properties of an adhesive (or sealant) by chemical reaction. (ASTM D 907-06)

curing agent, n
A substance or mixture of substances that controls a curing reaction. (ASTM D 907-06)

curing temperature, n
The temperature to which an adhesive or an assembly is subjected to cure the adhesive. (ASTM D 907-06)

curling, n
In pressure sensitive tapes, the tendency of a tape to curl back on itself when unwound from the rod and allowed to hang from the roll.

 

D

dead stretch, n
In pressure sensitive tapes, the net increase in length after tape has been elongated without breaking and allowed to recover.

delamination, n
The separation of layers in a laminate because of failure of the adhesive, either in the adhesive itself or at the interface between the adhesive and the adherend. (ASTM D 907-06); in pressure sensitive tapes, a separation or splitting of the tape such as separation of the backing into two distinct layers, separation between laminations of a tape con­sisting of more than one backing, or the separation between filaments and backing of a filament reinforced tape.

delayed strain, n
See latent strain.
Related Words  latent strain, n

depolymerization, n
Separation of a complex molecule into simple molecules; also softening of a sealant by the same action.

destructive test
See test, destructive.
Related Words  test, destructive, n

dextrin, n
A water based product derived from the acidification and/or roasting of starch.

dielectric curing, n
The use of a high frequency electric field through a joint to cure a synthetic thermosetting adhesive; a curing process for wood and other nonconductive joint materials.

dielectric strength, n
In pressure sensitive tapes, the voltage which a tape will withstand without allowing passage of the current through it.

diluent, n
A liquid additive, whose function is to reduce the concentration of solids or viscosity, or both, of an adhesive. (ASTM D 907-06)

discoloration, n
See stain.
Related Words  stain, n

dishing, n
See telescoping.
Related Words  telescoping, n

dispersion, n
A two-phase system in which one phase is suspended in a liquid. (ASTM D 907-06)

doctor blade, n
A scraper mechanism that regulates the dimensional thickness of adhesive on the spreader rolls or on the surface being coated. (Synonyms: doctor knife; doctor bar.) (ASTM D 907-06)

doctor roll, n
A revolving roller mechanism resulting in a wiping action for regulating the adhesive supplied to the spreader roll. (ASTM D 907-06)

double spread adhesive, n
An application of adhesive to both adherends or as two layers on one adherend. (ASTM D 907-06)

double spread, n
See double spread under spread.
Related Words  spread, n

double-coated, adj
In pressure sensitive tapes, the adhesive is applied on both sides of the backing, which serves principally as a car­rier for the adhesive.

dry bond adhesive, n
Synonym for contact adhesive.
Related Words  contact adhesive, n

dry strength, n
See bond strength.
Related Words  bond strength, n

dry tack, n
See dry tack under tack.
Related Words  tack, n

dry, v
To change the physical state of an adhesive on an adherend or between adherends by the loss of solvent constituents by evaporation or absorption, or both. (ASTM D 907-06)

drying agent, n
A component of a sealant that accelerates the oxidation of oils or unsaturated polymers.

drying temperature, n
The temperature to which an adhesive or an assembly is subjected to dry the adhesive. (ASTM D 907-06)

drying time, n
The period of time during which an adhesive or an assembly is allowed to dry, with or without the application of heat or pressure, or both. (ASTM D 907-06)

durability, n
As related to adhesive joints, the endurance of joint strength relative to the required service conditions. Discussion—Service conditions may include water and other chemicals, temperature, stress, radiation, microorganisms, and other environmental factors. (ASTM D 907-06); in building construction, a general term for resistance to deleterious change of an installed sealant. Discussion– Durability describes the ability of a sealant to maintain the required properties for its intended service. Durability is based on the length of time that a sealant can maintain its innate characteristics in use. This time will vary depending on the environment and use of the sealant (e.g. outdoor vs. indoor use). (ASTM C717-07a)

durometer, n
An instrument used to measure hardness or Shore A hardness; may also refer to the hardness rather than the instrument.

Back to Top

 

E

edge curl, n
The peeling back or lifting of the outer edge of a tape after application. (See cupping)
Related Words  cupping, n

edge joint
See joint.
Related Words  joint, n

elastic memory, n
A tendency of some tape back­ings to attempt to return to their original length after being elongated.

elasticity, n
The ability of a material to return to its original shape after removal of a load.

elastomer, n
A macromolecular material that can withstand large strains on short time scales without permanent plastic deformation. (ASTM D 907-06); a macromolecular material that returns rapidly to approximately its original dimensions and shape after substantial deformation by a weak force and release of the force (Note: Elastomers are divided into two major polymer systems – thermoset and thermoplastic) (ASTM C 717-07a)

electrolytic corrosion factor, n
A measure of the tape’s corrosive effect on a copper conductor. This is particularly important in the selection of tapes for use as electrical insulation.

elongation (stretch, ultimate elongation), n
The distance a tape will stretch lengthwise before breaking, expressed as a percentage of original length. Elongation is not necessarily an indication of conformability.

emulsion, n
A heterogeneous system in which an immiscible liquid is distributed in fine drops in another liquid. Discussion—The internal phase is sometimes described as the disperse phase. (ASTM D 907-06)

encapsulated adhesive, n
An adhesive in which the particles or droplets of one of the relative components are enclosed in a protective film (microcapsules) to prevent cure until the film is destroyed by suitable means.

epoxy, n
A resin formed by combining epichlorohydrin and bisphenols. Requires a curing agent for conversion to a plastic like solid. Has outstanding adhesion and excellent chemical resistance.

exothermic, adj
A chemical reaction that gives off heat.

extender, n
Substance added to an adhesive to reduce the amount of the primary binder required per unit area. (ASTM D 907-06)

extensibility, n
The ability of a sealant to stretch under tensile load.

extrudability, n
In building construction, the ability of a sealant under pressure to flow through an orifice. (ASTM C 717-07a)

extrusion failure, n
Failure that occurs when a sealant is forced too far out of a joint by compression forces. The sealant may be abraded by dirt or folded over by traffic.

 

F

face clearance, n
The distance between a glass plate and the edge of the stop.

face glazing, n
The method of glazing in which a rabbeted glazing recess, with no movable stop, is used and a triangular bead of compound is applied to the face of the lite and extended onto the recess (ASM C 717-07a).
Click here for figure.

failure, n
See adhesion failure, cohesion failure, extrusion failure, and fatigue failure
Related Words  adhesion (adhesive) failure, n; cohesion (cohesive) failure, n; extrusion failure, n ; fatigue failure, n

fall-off, n
Condition in which a tape pulls completely away from the surface to which it is applied and drops off.

fatigue failure, n
Failure of a material as a result of rapid cyclic deformation

faying surface, n
The surface of an adherend which makes contact with another adherend.

feathering, n
The tapering of an adherend on one side to form a wedge section, as used in a scarf joint; in pressure sensitive tapes, a jagged, irregular paint line frequently characterized by small “feathers” of the top-coat projecting into the masked area.

fiber tear, n
In an FRP adhesively bonded joint, failure occurring exclusively within the fiber reinforced plastic matrix, charisterized by the appearance of reinforcing fibers on both ruptured surfaces. (Also called fiber tear failure.) (ASTM D 907-06)

fiber-reinforced plastic (FRP), n
A plastic that contains fibers in various forms such as cloth, mat, strands, or chopped to enhance properties. (ASTM D 907-06)

filaments, n
In pressure sensitive tapes, thin longitudinal “threads” of glass, polyester, nylon, or other high strength materials.

filler sheet, n
Sheet of deformable or resilient material which, when placed between the assembly to be bonded and the pressure applicator, or when distributed within a stack of assemblies, aids in providing uniform application of pressure over the area to be bonded. (ASTM D 907-06)

filler, n
A solid material added to an adhesive to modify its strength, permanence, working properties, or other qualities, or to lower cost. (ASTM D 907-06)

fillet sealant joint, n
In building construction, a joint where sealant is applied over the joint to the face of substrates that are approximately perpendicular to each other. (ASTM C717-07a)
Click here for figure.

fillet, n
That portion of an adhesive which fills the corner or angle formed where two adherends are joined. (ASTM D 907-06)

film adhesive, n
An adhesive in film form, with or without a carrier, usually set by means of heat and/or pressure. The main advantage is uniformity of glueline thickness.

film, n
Uniform, homogenous, non-fibrous synthetic webs.

finger joint, n
See finger joint under joint.
Related Words  joint, n

finger tack, n
See quick stick.
Related Words  quick stick, n

fisheyes, n
In pressure sensitive tapes, relatively small deformations (pock-marks) in the adhesive caused by the entrapment of air between layers in the roll. Note this is not an indication of a quality defect.

flagging, n
In pressure sensitive tapes, a peeling away from the surface of the end of a length of tape, particularly in a spiral-wrap application.

flaking, n
In pressure sensitive tapes, a condition sometimes occurring during the removal of masking tape, in which flakes or particles of paint break off of the tape backing.

flame resistance, n
Ability of a tape to withstand exposure to flame. Flame Resistant (fire retardant, self-extinguishing) materials will burn when exposed to flame, but will not continue to burn after the flame is removed. Compare to fireproof materials, which will not burn even when exposed to flame.

flatback, n
In pressure sensitive tapes, smooth paper backing.

flexibility, n
Ability of a tape to be freely bent or flexed.

flow, n
Movement of an adhesive during the bonding process before the adhesive is set. (ASTM D 907-06)

fluorocarbon films, n
A film with very high and low temperature limits, and excellent electrical characteristics. Typically exhibit a very slippery, non-sticking surface. Note: One example is DuPont’s Teflon®.

foam, n
In pressure sensitive tape backing, a soft, cushiony material formed by creating bubbles in base materials, such as natural or synthetic rubbers, or other elastomeric materials.

foamed adhesive, n
An adhesive whose apparent density has been decreased by the presence of numerous gas-filled cells throughout its mass. (ASTM D 907-06)

four-side structural sealant glazing, n
In building construction, a glazing system wherein all sides of a rectangular-shaped lite or panel are structural sealant glazed. (ASTM C717-07a)

freezing, n
In pressure sensitive tapes, a hardening of the adhesive after application, so that tape cannot be easily or cleanly removed.

 

G

gap-filling adhesive, n
An adhesive capable of forming and maintaining a bond between surfaces that are not close-fitting. Discussion—Close-fitting is relative to a given material and industry; for example, standards in construction differ from standards in electronics. Some adhesives will bond by bridging without completely filling the gap, others by filling the gap completely. (ASTM D 907-06)

gapping, n
In pressure sensitive tapes, openings between layers of tape within a roll.

gasket, n
Any preformed, deformable device designed to be placed between two adjoining parts to provide a seal. (ASTM C 717-07a)

gel, n
A semisolid system consisting of a network of solid aggregates in which liquid is held. (ASTM D 907-06)

gelation, n
Formation of a gel. (ASTM D 907-06)

ghosting, n
See offsetting.
Related Words  offsetting, n

glass transition temperature (Tg), n
The temperature at which an adhesive will become markedly less elastic and flexible.

glazing compound, n
In building construction in glazing, a putty material composed primarily of oil- or resin-based ingredients used for sealing window glass in frames. Discussion—Historically these compounds cure primarily through solvent evaporation, oxidation or both. Compounds other than oil- or resin-based can be used for glazing, though they may not have a putty-like consistency. (ASTM C717-07a)

glazing, construction site, n
In building construction, the installation of glass or panels into a metal framing system, at a construction site, under generally uncontrolled environmental conditions. (ASTM C717-07a)

glazing, factory,
See glazing, shop.
Related Words  glazing, shop, n

glazing, field,
See glazing, construction site.
Related Words  glazing, construction site, n

glazing, protective, n
In building construction, systems with glazed openings that are designed to mitigate the effects of bomb blasts, projectiles, natural disasters, or forced entry. Discussion—Protective glazing systems assist in the mitigation of the potential for hazardous debris dispersal from natural disasters, withstand projectile impact and resist unauthorized human entry through glazed openings. Protective glazing systems include the selection of an appropriate glazing material, the design of metal framing members and their anchorages, and the retention of the glazing material within the framing all to resist a specified threat. (ASTM C717-07a)

glazing, shop, n
In building construction, the installation of glass or panels into a metal framing system under controlled environmental conditions. Discussion—Shop glazing typically occurs at a location remote to a construction site. However, shop glazing can be performed at the construction site if acceptable to the code authority and provided appropriate management controls and environmental conditions are maintained. (ASTM C717-07a)

glazing, v
In building construction, the installation of glass or other materials in prepared openings. (ASTM C717-07a)
Click here for figure representing typical glazing profiles.
Related Words  channel glazing, n ; face glazing, n

gloss, n
In pressure sensitive tapes, an appearance characteristic of tape back­ings. Usually expressed by such terms as glossy, low gloss, matte, etc.

glue (archaic), n
A hard gelatin obtained from hides, tendons, cartilage, bones, etc., of animals, and also an adhesive prepared from this substance by heating with water. See adhesive, n. (ASTM D 907-06)
Related Words  adhesive (n)

glue line, n
Synonym for bondline.
Related Words  bondline, n

glue, v
See bond, v.
Related Words  bond, v

glue-laminated wood, n
See glue-laminated wood under wood laminates.
Related Words  wood laminates, n

GLULAM, n
Synonym for structural-glued-laminated timber.
Related Words  structural-glued-laminated timber, n

gum, n
Any of a class of colloidal substances, exuded by or prepared from plants, sticky when moist, composed of complex carbohydrates and organic acids, which are soluble or swell in water. (See also adhesive and resin.) Discussion—The term gum is sometimes used loosely to denote various materials that exhibit gummy characteristics under certain conditions, for example, gum balata, gum benzoin, and gum asphaltum. Gums are included by some in the category of natural resins. (ASTM D 907-06)
Related Words  adhesive (n); resin, n

gunability, n
The ability of a sealant to extrude out of a cartridge in a caulking gun.

gun-grade, n
In building construction, a material of a suitable viscosity to extrude through the nozzle of a hand- or power-operated device. (ASTM C717-07a)

gypsum wallboard, n
A sandwich type material. Gypsum plaster with a heavy paper coating on both sides. When fastened directly to studs, it forms a wall surface.

 

H

hardboard, n
Fine pieces of wood bound together with an adhesive and pressed into sheets. Thermosetting resins are used as the adhesive binder.

hardener, n
Synonym for curing agent.
Related Words  curing agent, n

hardness, n
In building construction, the resistance to indentation as measured under specified conditions (ASTM C 717-07a); typically measured using a Durometer; on a Shore A Durometer scale, numbers range from 0 to 100 for rubber-like materials.

head, n
The top member of a window or door frame.

heat activated adhesive, n
A type of adhesive pre-applied to one or both adherends, that is rendered tacky by application of heat and forms a bond on cooling. (ASTM D 907-06)

heat resistance, n
The ability of a tape to with­stand exposure to specified temperatures after applica­tion to a surface. Clean removal after exposure may or may not be important depending on the intended func­tion of the tape and the type of adhesive.

heel bead, n
The ability of a tape to with­stand exposure to specified temperatures after applica­tion to a surface. Clean removal after exposure may or may not be important depending on the intended func­tion of the tape and the type of adhesive.

high temperature crossover (TxOver), n
Temperature at which an adhesive loses its elastomeric properties and melts to a flowable liquid. This value is a stability indicator for high temperature applications. For example, the higher the value, generally, the more heat stable the product is.

high-speed unwind, n
The unwinding or dispensing of tapes at a relatively high rate of speed, usually over 50 feet per minute.

Hochman test cycle, n
The bond durability test cycle used in ASTM C 920.

holding power (shear adhesion), n
The ability of a tape to resist the static forces applied in the same plane as the backing. Usually expressed in terms of time required for a given weight to cause a given amount of tape to come loose from a vertical panel.

holiday, n
A small defect, particularly in an electrical or pipe wrapping tape, which lowers the dielectric strength at the point of the defect below a certain desired minimum.

hot-melt adhesive, n
A thermoplastic adhesive that is applied in a molten state and forms a bond upon cooling to a solid state. (ASTM D 907-06); a pressure sensitive adhesive applied to a tape backing in a molten form which then cools to form a conventional pressure sensitive.

hot-setting adhesive, n
A thermoplastic adhesive that is applied in a molten state and forms a bond upon cooling to a solid state. (ASTM D 907-06); a pressure sensitive adhesive applied to a tape backing in a molten form which then cools to form a conventional pressure sensitive.

hypalon, n
A chlorosulfonated polyethylene synthetic polymer that is a base for making solvent based sealants.

 

I

impact resistance (shock resistance), n
The ability of a tape to resist sudden pulls or shocks as may some­times be encountered by packages in transit.

impact strength, n
The kinetic energy per area absorbed by an adhesively-bonded joint when fractured by shock loading. (ASTM D 907-06)

inhibitor, n
A substance used to suppress a chemical reaction. (ASTM D 907-06); a substance added to slow down the cure rate of a sealant.

insulation resistance, n
The ability of a tape to prevent the flow of current across its surface, usually measured on the backing.

intermediate-temperature-setting adhesive, n
An adhesive that sets in the temperature range from 31 to 99°C (87 to 211°F). (Synonym warm-setting adhesive.) (Compare cold-setting adhesive, hot-setting adhesive, and room-temperature-setting adhesive.) (ASTM D 907-06)
Related Words  cold-setting adhesive, n; hot-setting adhesive, n; room-temperature-setting adhesive, n; warm-setting adhesive, n

interphase, n
In an adhesive joint, a region of finite dimension extending from a point in the adherend where the local properties (chemical, physical, mechanical, and morphological) begin to change from the bulk properties of the adherend to a point in the adhesive where the local properties equal the bulk properties of the adhesive. (ASTM D 907-06)

 

J

joint aging time, n
Synonym for joint conditioning time.
Related Words  joint conditioning time

joint conditioning time
The time interval between the removal of the joint from the conditions of heat or pressure, or both, used to accomplish bonding and the attainment of approximately maximum bond strength. (Synonym joint aging time.) (See also curing time, drying time, and setting time.) (ASTM D 907-06)
Related Words  cure, curing time, n; drying time, n; joint aging time, n; setting time, n

joint filler, n
A compressible material used in a partial or totally filled expansion, control, or isolation joint by its permanent placement in or between building materials such as concrete or masonry during construction; sometimes used as a sealant backing in a partially filled joint. (ASTM C 717-07a)

joint, n
Adhesive joint, n—location at which two adherends are held together with a layer of adhesive. (See also bond, n);
finger joint, n—a joint formed by bonding two precut members shaped like fingers.  Click here for figure.
laminate joint, n—in wood bonding, a joint made by bonding layers of adherends face to face to form thicker stock.;
lap joint, n— a joint made by placing one adherend partly over another and bonding together the overlapped portions.;
scarf joint, n— a joint made by cutting away similar angular segments of two adherends and bonding the adherends with the cut areas fitted together.;
starved joint, n— a joint that has an insufficient amount of adhesive to produce a satisfactory bond. Discussion—This condition may result from too thin a spread to fill the gap between the adherends, excessive penetration of the adhesive into the adherend, too short an assembly time, or the use of excessive pressure. (ASTM D 907-06)
Related Words  bond, n

 

K

knife-grade, n
In building construction, a compound of such consistency that it is generally applied with a knife or spatula hand tool. (ASTM C 717-07a)

 

L

label stock, n
Pressure sensitive materials, which are usually printed, frequently die-cut, furnished in roll or sheet form with a liner, and intended for use as labels.

laitance, n
In building construction, a weak layer of cement and aggregate fines on a concrete surface that is usually caused by an overwet mixture, overworking the mixture, improper or excessive finishing, or combinations thereof. (ASTM C 717-07a)

laminate joint
See joint.
Related Words  joint, n

laminate, n
Product made by bonding together two or more layers of material or materials.
cross laminate, n—a laminate in which some of the layers of material are oriented at right angles to the remaining layers with respect to the grain or strongest direction in tension.  Discussion—Balanced construction of the laminations above the center line of the thickness of the laminate is normally assumed.
parallel laminate, n—a laminate in which all the layers of material are oriented approximately parallel with respect to the grain or strongest direction in tension. (ASTM D 907-06)

laminate, v
To bond layers of material(s).

laminated veneer lumber (LVL), n
Lumber made by laminating veneers in which the grain of all the veneers is essentially parallel to the lengthwise dimension. laminated wood product, n –See wood laminates.
Related Words  wood laminates, n

lamination, n
1 ) The process of preparing a laminate. 2) any layer in a laminate. (Compare laminate, n and wood laminate.) (ASTM D 907-06) 3) in pressure sensitive tapes, a combination of two or more similar or dissimilar materials, which function as one backing (e.g. acetate and tissue in acetate fiber tapes).
Related Words  laminate, n; wood laminates, n

lap joint, n
A joint made by placing one adherend partly over another and bonding together the overlapped portions. (ASTM D 907-06); a joint in which the component parts overlap so that the sealant or adhesive is placed into shear action.

lap sealant joint, n
In building construction, a joint where sealant is applied within the joint between approximately parallel substrates that are face-to-face. (ASTM C 717-07a)
Click here for figure.

latent strain, n
A discoloration in a surface to which tape has been applied, which does not become noticeable until some time after removal, usually after the surface has been exposed to sunlight or heat.

latex caulks or sealants, n
A caulking compound or sealant using latex as the base raw material. The most common latex caulks are polyvinyl acetate and vinyl acrylic.

latex, n
A stable dispersion of polymeric substance in an essentially aqueous medium. (ASTM D 907-06); a colloidal dispersion of a rubber (synthetic or natural) in water, which is the base for a sealant.

layer, n
As related to veneer and plywood, a single veneer ply or two or more plies laminated with grain direction parallel. Discussion—A parallel laminated layer is two or more plies laminated with grain direction parallel. (ASTM D 907-06)

legging, n
The drawing of filaments or strings when adhesive-bonded substrates are separated. (See also stringiness and webbing.) (Compare teeth.) (ASTM D 907-06)
Related Words  stringiness, n; teeth, n; webbing, n

lifting, n
A situation where a section of tape has pulled away from the surface to which it has been applied.

lite, n
One piece of glazing (also spelled light), synonym: pane. (ASTM C 717-07a)

load transfer device, n
Any device embedded in the concrete on both sides of a pavement joint to prevent relative vertical movement of slab edges.

loop tack, n
The initial attraction or grab of an adhesive to a substrate without any external pressure. Measured in pounds per lineal inch (PLI).

 

M

manufactured unit, n
A quantity of finished adhesive or finished adhesive component, processed at one time. (Compare batch.) Discussion—The manufactured unit may be a batch or a part thereof. (ASTM D 907-06)
Related Words  batch, n

mass, n
In pressure sensitive tapes, sometimes used as another name for the adhesive.

mastic adhesive, n
A gap-filling adhesive applied as a paste or putty-like material. (Also called mastic.) (ASTM D 907-06)

mastic, n
See mastic adhesive.
Related Words  mastic adhesive, n

maturing temperature, n
The temperature, as a function of time and bonding condition, that produces desired characteristics in bonded components. Discussion—The term is specific for ceramic adhesives. (ASTM D 907-06)

mechanical adhesion, n
See mechanical adhesion under adhesion.
Related Words  adhesion, n

membrane pressing, n
A process in which an adherend is brought in intimate contact with a substrate to form an assembly by application of overpressure to a flexible film. (ASTM D 907-06)

mercaptan, n
An organic compound containing –SH groups; a main curing agent for polysulfide adhesives and sealants.

metal foil, n
Thin, flexible sheets of metal (e.g. aluminum and lead) used as tape backings because of inherent properties such as weather-resistance, reflectivity, etc.

migration, n
In pressure sensitive tapes, the movement, over a long period of time, of an ingredient from one component to another when the two are in surface contact. May occur between tape components or between a tape and the surface to which it is applied. Some plastic films and foams contain plasticizers, which are apt to migrate into the tape adhesive, causing the adhesive to soften.

modifier, n
Ingredient which, when added to an adhesive, changes its properties. (ASTM D 907-06)

modulus, n
As related to sealants used in building construction, the stress (force/unit area) at a corresponding strain (elongation) expressed as a percent of the original dimension. Discussion—When the stress to strain values are expressed as a ratio, this describes the slope of a line tangent to the given point on the stress-strain curve. This is the tangent modulus.
Related Words  modulus, tangent, n

modulus, secant, n
Slope of the line connecting the origin and a given point of the stress-strain curve. (ASTM C 717-07a)

modulus, tangent, n
Slope of the line touching (tangent to) the stress-strain curve at a given point on the curve. (ASTM C 717-07a)

monomer, n
A relatively simple compound which can react to form a polymer. (Compare polymer.) (ASTM D 907-06); a building block in the manufacture of polymers.
Related Words  polymer, n

mucilage, n
An adhesive prepared from a gum and water, and also in a more general sense, a liquid adhesive which has a low order of bonding strength. (See also adhesive, glue, paste, and sizing.) (ASTM D 907-06)
Related Words  adhesive (n); glue (archaic), n; paste, n; sizing, n

mullion, n
External structural member in a curtain wall building, usually vertical. May be placed between two opaque panels, between two window frames, or between a panel and a window frame.

multiple-layer adhesive, n
Film adhesive, usually supported, with a different adhesive composition on each side. (ASTM D 907-06)

MVT, n
Moisture vapor transmission, usually expressed in terms of grams of water per square meter per 24 hours.

 

N

neck down, n
The change in the cross section areas of a sealant as it is extended.

needle glazing
In building construction, the application of a small bead of a sealant at the sight line adhering to the sash and glass or panel by means of a nozzle with an orifice not exceeding 3.18 mm [1 /8 in.] in diameter. (ASTM C 717-07a)

Newtonian behavior, n
The property of a liquid in which its viscosity is constant over a stated range of strain rates. (Compare non-Newtonian behavior.) (ASTM D 907-06)
Related Words  non-Newtonian behavior, n

nominal stress, n
The stress at a point calculated on the net cross section by simple elastic theory without taking into account the effect on the stress produced by discontinuities such as holes, grooves, fillets, or any combination of them. (ASTM D 907-06)

non-compression glazing system, n
In building construction, a sealant or combination of sealant(s) used to provide weather-tightness by way of the adhesive/cohesive characteristics of the components in the joint. (ASTM C 717-07a)

non-compression glazing, v
In building construction, the act of installing components into a non-compression glazing system. (ASTM C 717-07a)

non-destructive test
See test, non-destructive.
Related Words  test, nondestructive, n

non-Newtonian behavior, n
The property of a liquid in which its viscosity is not constant over a stated range of strain rates. (ASTM D 907-06)

nonvolatile content, n
The portion of a material that remains after volatile matter has been evaporated under specified ambient or accelerated conditions. (See solids content.) Discussion—The measured percentage of nonvolatile matter in an adhesive will vary according to the analytical procedure. A standard test method must be used to obtain consistent results. (ASTM D 907-06)

non-woven materials, n
Paper “tissues” or synthetic (e.g. rayon) non-woven fabrics.

novolak, n
A phenolic resin containing less than a 1:1 ratio of formaldehyde to phenol so that normally it remains thermoplastic until heated with an appropriate amount of a compound (for example, formaldehyde or hexamethylenetetramine) capable of giving additional linkages, thereby producing an infusible material. (ASTM D 907-06)

 

O

off-core, adj.
Condition in which ayers of tape are in correct alignment, but tape is displaced sideways on core.

offsetting, n
Cndition occurs when a printed tape is unwound and some of the printing ink is picked off by the adhesive or migrates into the adhesive. It is in effect a delamination of the ink.

oil (drying), n
An oil that dries to a hard, vanish like film. Linseed oil is common example.

oozing, n
In pressure sensitive tapes, a “squeezing out” of the adhesive from under the backing. When this occurs during the time in which the tape is in roll form, the edges of the roll become tacky.

opaqueness, n
In pressure sensitive tapes, the ability of a tape to prevent the transmission of light.

open assembly time, n
Interval between adhesive application to the adherends and assembly of the adhesive joint.

open cell material, n
A cellular material in which substantially all cells in the mass are open cells. (ASTM C 717-07a)

open cell sealant backing, n
In building construction, a flexible and very compressible fabricated shape (usually cylindrical), without a surface skin, that is composed of open cell material. (ASTM C 717-07a)

open time, n
Time interval from when an adhesive is applied to when in becomes unworkable.

outgassing, n
The emission of occluded gasses from a material by vacuum, heat, or pressure. Discussion—As applied to sealant backing materials contained within a filled joint, outgassing may occur when it is compressed or punctured causing gas bubbles to form in the overlying sealant. (ASTM C 717-07a)

 

P

paint line, n
The line between a tape masked surface and a painted or otherwise treated surface.

parallel laminate, n
See parallel laminate under laminate, n. (ASTM D 907-06)
Related Words  laminate, n

particle board, n
Same as hardboard, except that larger wood chips are used as the filler.

paste, n
An adhesive composition having a characteristic plastic-type consistency, that is, a high order of yield value, such as that prepared by heating a mixture of starch and water and subsequently cooling the hydrolyzed product. (Compare adhesive, glue, mucilage, and sizing.) (ASTM D 907-06)
Related Words  adhesive (n); glue (archaic), n; mucilage, n; sizing, n

pavement growth, n
An increase in the length of a pavement caused by incompressibles working into the joints.

peak load, n
Maximum force recorded during a strength test. (ASTM D 907-06)

peaking, n
In pressure sensitive tapes, large singular upheavals in the outer layers of a roll of tape.

peel adhesion, n
The force per unit width, typically expressed in oz/in width (US), required to break the bond between a tape and a surface when peeled back usually at 180 degrees at a standard rate and condition. See peel test.
Related Words  peel test, n

peel strength, n
The average load per unit width of bondline required to separate progressively a flexible member from a rigid member or another flexible member. Discussion—Flexible has different meanings in different peel tests, such as “T,” 180-degree, floating-roller, or climbing drum. The angle between the members varies with the type of peel test. (ASTM D 907-06)

peel test, n
A test of an adhesive or sealant using one rigid and one flexible substrate. The flexible material is folded back (usually 90 or 180 degrees) and the substrates are peeled apart. Strength is usually measured in pounds per inch of width (PLI).

penetration resistance, n
The ability of a tape to resist slow puncture under pressure.

penetration, n
The entering of an adhesive into an adherend. Discussion—This property of a system is measured by the depth of penetration of the adhesive into the adherend. (ASTM D 907-06)

permanence, n
Resistance to appreciable changes in characteristics with time and environment. (ASTM D 907-06)

permanent set, n
The amount of deformation that remains in a sealant or adhesive after removal of a load.

phenolic resin, n
A thermosetting resin; usually formed by the reaction of phenol with formaldehyde.

physical cure, n
Cure by applied heat or evaporation. Discussion — Physically curing adhesives are already present in their final chemical state upon application.

pick-up roll, n
The part of a spreading device that runs in a bath or reservoir of adhesive. (ASTM D 907-06)

pin-and-collar specimen, n
An assembly of a metal pin bonded inside a metal collar, used to measure the shear strength of an adhesive. (ASTM D 907-06)
Click here for figure.

pinhole, n
In pressure sensitive tapes, a very small hole, which, may permit the passage of fight, moisture or electrical current.

plain cloth, n
In pressure sensitive tapes, fabric woven from cotton, glass or other fibers, without further treatment.

plasticity, n
A property of a material that allows the material to be deformed continuously and permanently without rupture upon the application of a force that exceeds the yield value of the material. (ASTM D 907-06)

plasticizer, n
A substance of low or negligible volatility that lowers the softening range and increases workability, flexibility or extensibility of a polymer. (ASTM D 907-06)

plastisol, n
A physical mixture of resin (usually vinyl) compatible plasticizers and pigments. Mixture requires fusion at elevated temperatures in order to convert the plastisol to a homogeneous plastic material.

PLI, n
Pounds per linear inch, unit of measure associated with peel test. See peel test.
Related Words  peel test, n

plywood, n
See plywood under wood laminates.
Related Words  wood laminates, n

poise, n
Measure of viscosity (in cgs units).
Related Words  viscosity, n

polycondensation, n
See condensation.
Related Words  condensation, n

polyester, n
In pressure sensitive tapes, a strong film, usually transparent, having good resistance to moisture, solvents, oils, caustics, and many other chemicals.

polyethylene, n
A tough, stretchy film having very good low temperature characteristics.

polymer, n
Acompound formed by the reaction of simple molecules having functional groups which permit their combination to proceed to higher molecular weights under suitable conditions. Discussion—Polymers may be formed by polymerization (additional polymer) or polycondensation (condensation polymer). When two or more monomers are involved, the product is called a copolymer. (ASTM D 907-06)

polymerization, n
A chemical reaction in which the molecules of a monomer(s) are linked together in repeating units to form larger molecules. (ASTM D 907-06)

polypropylene, n
A new cousin of polyethylene, with generally similar properties, but stronger and hav­ing a higher temperature resistance.

polyvinyl acetate emulsion adhesive, n
A latex adhesive in which the polymeric portion comprises polyvinyl acetate, copolymers based mainly on polyvinyl acetate, or a mixture of these, and which may contain modifiers and secondary binders to provide specific properties. (ASTM D 907-06)

polyvinylidene chloride (PVDC), n
In pressure sensitive tapes, a usually very thin transparent film with excellent resistance to acids, water and organic solvents.

postcure, n
In pressure sensitive tapes, a usually very thin transparent film with excellent resistance to acids, water and organic solvents.

postcure, v
After the initial cure, to further treat an adhesive by time or temperature, or both, to modify specific properties. (ASTM D 907-06)

pot life (working life), n
After the initial cure, to further treat an adhesive by time or temperature, or both, to modify specific properties. (ASTM D 907-06)

pre-bond treatment, n
Synonym for surface preparation.
Related Words  surface preparation, n

preproduction test, n
A test or series of tests conducted by (1) an adhesive manufacturer to determine conformity of an adhesive batch to established production standards, (2) a fabricator to determine the quality of an adhesive before parts are produced, or (3) an adhesive specification custodian to determine conformance of an adhesive to the requirements of a specification not requiring qualification tests. (Compare acceptance test and qualification test.) (ASTM D 907-06)
Related Words  acceptance test, n; qualification test, n

pressure-sensitive adhesive (PSA), n
A viscoelastic material which in solvent-free form remains tacky and will adhere instantaneously to most solid surfaces with the application of very slight pressure. (ASTM D 907-06). Discussion—pressure sensitive adhesives require no activation by water, solvent or heat in order to exert a strong adhesive holding force toward such materials as paper, plastic, glass, wood, cement and metals. They have a suf­ficiently cohesive holding and elastic nature so that, despite their aggressive tackiness, they can be handled with the fingers and removed from smooth surfaces without leaving a residue. General trade usage by lead­ing tape manufacturers does not sanction extension of the term “pressure-sensitive” to embrace tapes and adhesives merely because they are sticky (e.g. fly­papers), or merely because they adhere or cohere to a particular type of surface (e.g. self-sealing envelopes); terms other than “pressure-sensitive” should be used in such cases to avoid confusion.

pressure-sensitive article, n
A combination of a pressure-sensitive adhesive with a backing or with a backing and release liner. Discussion—Examples of such articles include tapes, labels, stickers and handspreads;
transfer failure, n –in characterizing the locus of failure in a pressure-sensitive article, separation at the interface of adhesive and backing. (ASTM D 907-06)

primer, n
A coating applied to a surface, prior to the application of an adhesive, to improve the performance of the bond. (ASTM D 907-06)

priming, n
Applying a coating to improve the performance of the bond; in pressure sensitive tapes, coating the backing on the adhesive side with a thin layer of adhesive-like material, which serves as a bonding agent between the adhesive and the backing.

printability, n
The ability of a tape to accept and hold a printed legend, and especially to resist offset of the printing when rewound into a roll after printing.

proportional limit, n
The maximum stress that a material is capable of sustaining without significant deviation from proportionality of stress to strain. (ASTM D 907-06)

puckering, n
The uneven, non-flat condition of mask­ing paper to which tape has been applied.

putty, n
In building construction, a knife-grade compound generally used as a glazing compound or to fill cracks or holes. (ASTM C 717-07a)

 

Q

qualification test, n
A series of tests conducted by the procuring activity, or an agent thereof, to determine conformance of materials, or materials system, to the requirements of a specification which normally results in a qualified products list under the specification. (Compare acceptance test and preproduction test.) Discussion—Generally, qualification under a specification requires a conformance to all tests in the specification, or it may be limited to conformance to a specific type or class, or both, under the specification. (ASTM D 907-06)
Related Words  acceptance test, n; preproduction test, n

quick stick, n
Also known as quick tack, finger tack, initial adhesion, wet grab — the property of a pressure sensitive adhesive which allows it to adhere to a surface under very light pressure; it is determined by the ability of the adhesive to quickly wet the surface contacted.

Back to Top

 

R

rate of creep, n
The slope of the creep-time curve at a given time. (ASTM D 907-06)

recovery, n
In pressure sensitive tapes, the difference between ultimate elonga­tion and dead stretch.

reflection crack, n
A crack through a bituminous overlay on Portland cement concrete pavement. The crack occurs above any working joint in the base pavement.

reinforcement, n
in sealants, this is the increase in modulus, toughness, tensile strength, by the addition of selected fillers; in pressure sensitive tapes, material added to a tape to provide additional strength.

release agent, n
An adhesive material which prevents bond formation.

release coat transfer, n
Condition in which particles of the release coat stick to the adhesive during the unwind phase — result­ing tape will have little or no ability to stick.

release coating, n
A coating applied to the backing on the side opposite the adhesive, which provides ease of unwind, and prevents delamination or tearing.

release liner, n
A web or sheet of material covering the adhesive side of a tape. It is removed prior to appli­cation. Most frequently found on double-coated tapes and label stocks.

release paper, n
A sheet, serving as a protectant or carrier, or both, for an adhesive film or mass, which is easily removed from the film or mass prior to use. (ASTM D 907-06)

removal, n
In pressure sensitive tapes, the act of pulling tape away from the surface to which it has been applied.

resilience, n
A measure of energy stored and recovered during a loading cycle. It is expressed as a percentage.

resin, n
Solid, semisolid, or liquid, usually organic material that has an indefinite molecular mass and, when solid, usually has a softening or melting range and exhibits a tendency to flow when subjected to stress. (ASTM D 907-06)

resinoid, n
Any of the class of thermosetting synthetic resins, either in their initial temporarily fusible state or in their final infusible state. (See also novolak and thermoset.) (ASTM D 907-06)
Related Words  novolak, n; thermoset, n, adj

retarder, n
Synonym for inhibitor.
Related Words  inhibitor, n

reverse stain, n
See bleaching.
Related Words  bleaching, n

ridging, n
In pressure sensitive tapes, a mound-like swelling on the outer layers of a roll, lengthwise to the tape. Usually found on the more moisture sensitive materials, such as cellophane.

room-temperature-setting adhesive, n
An adhesive that sets in the temperature range from 20 to 30°C (68 to 86°F), in accordance with the limits for Standard Room Temperature specified in ASTM D618. (Compare cold-setting adhesive, hot-setting adhesive, and intermediate-temperature-setting adhesive.) (ASTM D 907-06)
Related Words  cold-setting adhesive, n; hot-setting adhesive, n; intermediate-temperature-setting adhesive, n

rope stock, n
In pressure sensitive tapes, a smooth paper made of hemp fiber for high tensile strength.

rosin, n
A resin obtained as a residue in the distillation of crude turpentine from the sap of the pine tree (gum resin) or from an extract of the stumps and other parts of the tree (wood rosin). (Compare resin.) (ASTM D 907-06)
Related Words  resin, n

RTV, n
Room temperature vulcanization. (ASTM D 907-06)
Related Words  vulcanization, n

 

S

SAFT, n
Abbreviation for Shear Adhesion Failure Temperature.
Related Words  shear adhesion failure temperature (SAFT), n

sag, n
In building construction, the gravity-induced downward flow of a sealant or glazing compound, resulting in an uneven thickness, when applied on a vertical surface. (ASTM C 717-07a)

saturation (impregnation), n
In pressure sensitive tapes, the process of adding materials (saturant) to the backing for improvement of physical properties, and resistance to various deleterious environments. The backing of paper tapes, for instance, may actually contain as much as 50% by weight of a rubber-based impregnant.

scarf joint, n
See scarf joint under joint.
Related Words  joint, n

seal, n
In building construction, a barrier against the passage of liquids, solids, or gases. (ASTM C 717-07a)

sealant (n)
In building construction, a material that has the adhesive and cohesive properties to form a seal (ASTM C 717-07a)

sealant backing
In building construction, a compressible material placed in a joint before applying a sealant. Discussion—The purpose of the sealant backing is to assist in providing the proper sealant configuration, to limit the depth of the sealant, and in some cases, to act as a bond breaker. (ASTM C 717-07a)

sealant, aerosol foam, n
In building construction, a sealant that expands in volume as it is dispensed from a container, using propellant under pressure, to form a rigid or semi-rigid cellular mass. (ASTM C 717-07a)

sealant, aerosol foam, straw-type, n
In building construction, an aerosol foam sealant that is extruded through a narrow tube. Discussion—A straw-type dispenser is attached to the valve of the container and is controlled by a lever actuator-connector. (ASTM C 717-07a)

sealant, chemically curing, n
In building construction, a compound that cures primarily through chemical reaction. (ASTM C 717-07a)

sealant, emulsion
See sealant, latex.
Related Words  sealant, latex, n

sealant, hot-applied, n
In building construction, a compound that is applied in a molten state and cures primarily by cooling to ambient temperatures. Discussion—A hot-applied sealant is sometimes called a hot-melt sealant. (ASTM C 717-07a)

sealant, latex, n
In building construction, a compound that cures primarily through water evaporation. Discussion—The terms latex sealant and emulsion sealant are sometimes used interchangeably. (ASTM C 717-07a)

sealant, non-sag, n
In building construction, a compound that exhibits little or no flow when applied in vertical or inverted joints. (ASTM C 717-07a)

sealant, precured, n
In building construction, a sealant having encapsulated therein solids or discrete particles that limit its deformation within a joint under compression. Discussion—The sealant may be in tape or bulk form. Encapsulated solids or particles may include such materials as continuous rods of resilient plastic or rubber, glass beads, or string, which act as shims or space fillers. (ASTM C 717-07a)

sealant, preshimmed tape, n
In building construction, a preshimmed sealant in tape sealant form.  Discussion—The shim is usually a continuous plastic or rubber rod or discrete particles placed within the body of the tape sealant to regulate the compressibility of the tape sealant. See also sealant, tape and sealant, preshimmed. (ASTM C 717-07a)
Related Words  sealant, preshimmed, n; sealant, tape, n

sealant, preshimmed, n
In building construction, a sealant having encapsulated therein solids or discrete particles that limit its deformation within a joint under compression. Discussion—The sealant may be in tape or bulk form. Encapsulated solids or particles may include such materials as continuous rods of resilient plastic or rubber, glass beads, or string, which act as shims or space fillers. (ASTM C 717-07a)

sealant, self-leveling , n
In building construction, a compound that exhibits flow sufficient to seek gravitational leveling. (ASTM C 717-07a)

sealant, silicone, n
In building construction, a liquid-applied curing compound based on polymer(s) of polysiloxane structures. (ASTM C 717-07a)

sealant, solvent-release, n
In building construction, a compound that cures primarily through solvent evaporation. (ASTM C 717-07a)

sealant, structural, n
In building construction, a sealant capable of transferring dynamic or static (“live” or “dead,” or both) loads, or both, across joint members exposed to service environments typical for the structure involved. (ASTM C 717-07a)

sealant, tape, n
In building construction, a sealant having a preformed shape, and intended to be used in a joint initially under compression. (ASTM C 717-07a)

sealer, n
Surface coating generally applied to fill cracks, pores, or voids in a surface.

secant modulus, n
The slope of the secant drawn from the origin to any specified point on the stress-strain curve. (ASTM D 907-06)

self-curing, adj
See self-vulcanizing.
Related Words  self-vulcanizing, adj

self-leveling sealant, n
A sealant that is fluid enough to be poured into horizontal joints. It forms a smooth, level surface without tooling.

self-vulcanizing, adj
Pertaining to an adhesive that undergoes vulcanization without the application of heat. (See also vulcanization, n .) (ASTM D 907-06)
Related Words  vulcanization, n

separate-application adhesive, n
A term used to describe an adhesive consisting of two parts, one part being applied to one adherend and the other part to the other adherend and the two brought together to form a joint. (ASTM D 907-06)

service life, n
In building construction, the period of time an installed sealant is reasonably expected to function successfully without replacement or significant repair, assuming reasonable or expected periodic maintenance is performed. (ASTM C 717-07a)

set, v
To convert an adhesive into a fixed or hardened state by phsyical or chemical action, such as condensation, polyerization, oxidation, vulcanization, gelation, cooling, hydration, or evaporation of volatile constituents (See also cure and dry). (ASTM D 907-06)
Related Words  cure, v; dry, v

setting temperature, n
The temperature to which an adhesive or an assembly is subjected to set the adhesive. (See also curing temperature and drying temperature.) Discussion—The temperature attained by the adhesive in the process of setting (adhesive setting temperatures) may differ from the temperature of the atmosphere surrounding the assembly (assembly setting temperature). (ASTM D 907-06)

setting time, n
The period of time necessary for an adhesive in an assembly to set under specified conditions of temperature or pressure, or both. (ASTM D 907-06)

shape factor, n
The width-to-depth proportions of a field molded sealant.

shear adhesion failure temperature (SAFT), n
Refers to the upper temperature limit at which an adhesive is able to support a certain amount of weight. Polymer degradation, incorrect raw material ratios and incorrect blending can affect the SAFT results. This is not a measure of the bond between the adhesive and a substrate, but a measure of the internal strength of the adhesive itself. Generally, as the shear strength of an adhesive system in increased, tack and adhesive performance will decrease.

shear modulus, n
The ratio of shear stress to corresponding shear strain below the proportional limit. (Compare secant modulus.) (See proportional limit.) Discussion—The term shear modulus is generally reserved for materials that exhibit linear elastic behavior over most of their stress-strain diagram. Many adhesives exhibit curvilinear or nonelastic behavior, or both, in which case some other term, such as secant modulus, may be substituted. (ASTM D 907-06)
Related Words  proportional limit, n; secant modulus, n

shear strain, n
The angular change, expressed in radians, between two lines originally perpendicular to each other, due to shear stress. (ASTM D 907-06)

shear strength, n
An adhesive joint, the maximum average stress when a force is applied parallel to the joint. (See bond strength.) Discussion—In most adhesive test methods, the shear strength is actually the maximum average stress at failure of the specimen, not necessarily the true maximum stress in the material. (ASTM D 907-06)
Related Words  bond strength, n

shear, n
In an adhesively-bonded joint, stress, strain or failure resulting from applied forces that tends to cause adjacent planes of a body to slide parallel in opposite directions. (ASTM D 907-06)

shelf life, n
Synonym for storage life.
Related Words  storage life, n

Shore A hardness, n
The measurement of firmness of a rubbery compound or sealant by means of a Durometer hardness gauge; numbers range from 0 to 100 for rubber-like materials.

shortness, n
A qualitative term that describes an adhesive that does not string, cotton, or otherwise form filaments or threads during application. (ASTM D 907-06)

shrinkage, n
The volume reduction occurring during adhesive curing, sometimes expressed as percentage volume or linear shrinkage; size reduction of adhesive layer due to solvent loss or catalytic reaction; in pressure sensitive tapes, a reduction in any dimension of a tape.

silicone adhesive, n
A pressure-sensitive adhesive capable of functioning effectively at extreme temperatures.

silicone, adj
In pressure sensitive tapes, a unique polymer system which can be a very effective release coating;

single spread, n
See single spread under spread.
Related Words  spread, n

single-faced, adj
In pressure sensitive tapes, the adhesive is applied to one side of the backing only. Most pressure-sensitive tapes are of this type.

size (sizing), n
Application of a material (sealer, size) to the surface of an adherend, prior to that of the adhesive, in order to reduce the absorbency of the adherend. (ASTM D 907-06)

sized, adj.
Referring to fabric, usually cotton, treated to give added stiffness and easier handling.

sizing, n
The process of applying a material on a surface in order to fill pores and thus reduce the absorption of the subsequently applied adhesive or coating or to otherwise modify the surface properties of the substrate to improve the adhesion, and also, the material used for this purpose. (Synonym size.) (See also primer.) (ASTM D 907-06)
Related Words  primer, n; size (sizing), n

skewed joints, n
Transverse joints in a pavement slab, which are placed at an angle and not perpendicular to the direction of traffic.

slip sheet (interliner), n
A treated sheet used to cover the adhesive to facilitate handling.

slippage, n
The movement of adherends with respect to each other during the bonding process. (ASTM D 907-06)

slivering, n
In pressure sensitive tapes, tape tears or breaks into small pieces, either on unwind or removal from a surface.

smoothness, n
In pressure sensitive tapes, the relative flatness of the tape backing.

softening point, n
The temperature at which an adhesive goes from a solid to a molten form, measured in Fahrenheit or Celsius.

solids content, n
The percentage by weight of the nonvolatile matter in an adhesive. (See nonvolatile content.) (ASTM D 907-06)
Related Words  nonvolatile content, n

solvent adhesive, n
An adhesive having a volatile organic liquid as a vehicle. Discussion—This term excludes water-based adhesives. (ASTM D 907-06)

solvent reactivating, n
The application of solvent to a dry adhesive layer to regenerate its wetting properties.

solvent welding, n
The process of joining articles made of thermoplastic resins by applying a solvent capable of softening the surfaces to be joined and pressing the softened surfaces together. Adhesion is attained by means of evaporation of the solvent, absorption of the solvent into the adjacent materials and/or polymerization of the solvent cement.

solvent-activated adhesive, n
A dry adhesive on an adherend that is rendered tacky just prior to use by application of a solvent. (ASTM D 907-06)

spalling, n
A surface failure of concrete, usually occurring at the joint. It may be caused by incompressibles in the joint, by overworking the concrete, or by sawing joints too soon.

specific adhesion, n
See specific adhesion under adhesion.
Related Words  adhesion, n

spread, n
The quantity of adhesive per unit of area applied to an adherend. double spread, n — application of adhesive to both adherends of a joint. single spread, n — application of adhesive to only one adherend of a joint. (ASTM D 907-06)

squeeze-out, n
Adhesive pressed out of the joint during the bonding process. (ASTM D 907-06)

stabilizer, n
An adhesive additive which prevents or minimizes change in properties, e.g.., by adherend absorption, demulsification, or rapid chemical reaction.

stain resistance, n
The ability of a tape to be applied to a surface without discoloring the surface.

stain, n
A discoloration of a surface to which tape has been applied.

starved joint, n
See starved joint under joint.
Related Words  joint, n

stiffness, n
The measure of a tape’s flexibility and conformability.

stopless glazing, n
The use of a sealant as a glass adhesive to keep glass in permanent position without the use of exterior stops.

storage life, n
The period of time during which a packaged adhesive (or sealant) can be stored under specified temperature conditions and remain suitable for use. (Synonym shelf life.) (Compare working life.) (ASTM D 907-06)
Related Words  shelf life, n; working life, n

storage stability (roll-aging resistance), n
The ability of a tape to retain its original properties after storage.

strain, n
The unit change due to stress, in the size or shape of a body referred to its original size or shape. (ASTM D 907-06); the change in length divided by the original length of a test specimen and expressed as a percentage.

strength, n
See bond strength.
Related Words  bond strength, n

stress relaxation, n
Reduction in stress in a material that is held in constant deformation for an extended period of time.

stress, n
Force exerted per unit area at a point within a plane. Discussion—Stress on a planar surface is identical at all points on the plane. Stress on a non-planar surface varies with the location of the point, depending upon the direction of the application of stress. (ASTM D 907-06)

stringiness, n
The property of an adhesive that results in the formation of filaments or threads when adhesive transfer surfaces are separated. (See also legging and webbing.) (Compare teeth.) Discussion—Transfer surfaces may be rolls, picker plates, stencils, etc. (ASTM D 907-06)
Related Words  teeth, n

structural adhesive, n
A bonding agent used for transferring required loads between adherends exposed to service environments typical for the structure involved. (ASTM D 907-06). An adhesive of proven reliability in engineering structural applications in which the bond can be stressed to a high proportion of its maximum failing load for long periods without failure.

structural sealant glazing, n
In building construction, a glazing system wherein a structural sealant is used to transfer loads between a lite or panel and a supporting framework, without mechanical fasteners or other methods of attachment. (C 717-07a)

structural-glued-laminated timber, n
An engineered, stress-rated product of a timber laminating plant comprising assemblies of specially selected and prepared wood laminations securely bonded together with adhesives, with the following characteristics: ( 1) The grain of all laminations is approximately parallel longitudinally, and (2) The laminations may be comprised of pieces end-joined to form any length, of pieces placed or glued edge-to-edge to make wider ones, or of pieces bent to curved form during gluing. (Synonym GLULAM) (ASTM D 907-06)
Related Words  GLULAM, n

substrate, n
A material upon which an adhesive or sealant is applied. (Compare adherend.) (ASTM D 907-06)

surface preparation, n
Physical or chemical treatments, or both, applied to adherends to render them suitable for bonding. (ASTM D 907-06)

syneresis, n
The exudation of small amounts of liquid by gels on standing. (ASTM D 907-06)

 

T

tack range, n
The period of time in which an adhesive will remain in the tacky-dry condition after application to an adherend, under specified conditions of temperature and humidity. (ASTM D 907-06)

tack, n
The property of an adhesive that enables it to form a bond of measurable strength immediately after adhesive and adherend are brought into contact under low pressure. (See also tack range and tacky-dry.)
aggressive tack, n — synonym for dry tack.
dry tack, n — the property of certain adhesives, particularly nonvulcanizing rubber adhesives, to adhere on contact to themselves at a stage in the evaporation of volatile constituents, even though they seem dry to the touch. (Synonym aggressive tack.) (ASTM D 907-06); in building construction, the sticky condition of the surface of an applied sealant (or adhesive). (ASTM C 717-07a)
Related Words  tack range, n; tacky-dry, adj

tackiness, n
The stickiness of the surface of a sealant or adhesive.

tacky-dry, adj
Pertaining to the condition of an adhesive when the volatile constituents have evaporated or been absorbed sufficiently to leave it in a desired tacky state. (ASTM D 907-06)

tear resistance, n
Ability of a tape to resist tearing, after a tear has been started by cutting or nicking the edge.

tear strength, n
The load required to tear apart a sealant specimen. ASTM test method D 624 expresses tear strength in pounds per inch of width.

tearing, n
Breaking or slivering of a tape during unwind.

teeth, n
The resultant surface irregularities or projections formed by the breaking of filaments or strings which may form when adhesive-bonded substrates are separated. (Compare legging, stringiness, and webbing.) (ASTM D 907-06)
Related Words  legging, n; stringiness, n; webbing, n

telegraphing, n
Condition in a laminate or other type of composite construction by which irregularities, imperfections, or patterns of an inner layer are visibly transmitted to the surface. (ASTM D 907-06)

telescoping, n
A sideways sliding of the tape layers, one over the other, such that the roll looks like a funnel or a telescope.

tensile strength, n
In an adhesive joint, the maximum tensile stress that a material is capable of sustaining calculated from the maximum load applied perpendicular to the joint divided by the original cross-sectional area of the joint. (ASTM D 907-06); in pressure sensitive tapes, the force required to break a piece of tape by pulling on opposite ends of the piece.

test, destructive, n
Tests involving the destruction of assemblies in order to evaluate the maximum performance of the adhesive bond.

test, nondestructive, n
Inspection tests for the evaluation of bond quality without damaging the assembly, e.g., ultrasonic, visual inspection, etc.

Tg, n
See glass transition temperature.
Related Words  glass transition temperature (Tg), n

thermoplastic, n, adj
Polymer or copolymer capable of being softened by heating and hardened by cooling. (ASTM D 907-06) Discussion—a thermoplastic adhesive becomes softer as temperature increases, regardless of the number of heating cycles to which it is exposed.

thermoset, n, adj
Monomer, polymer or copolymer, which when cured, changes into a substantially infusible and insoluble product. (ASTM D 907-06) Discussion—a thermosetting adhesive which sets up or hardens on first exposure to heat, and remains set regardless of subsequent temperature cycles.

thickness, n
Distance from one surface of either a tape, backing or adhesive to the other, usually expressed in mils or thousandths of an inch; usually measured under slight pressure with a special gauge or caliper.

thinner, n
A volatile liquid added to an adhesive to reduce the viscosity or other properties. (ASTM D 907-06)

thixotropy (non-sagging), n
A material that maintains shape unless agitated. A thixotropic sealant can be placed in a joint in a vertical wall and will maintain its shape or position without sagging during the curing process.

tooling time, n
Of a sealant, the time interval after application of a one-component sealant or after mixing and application of a multi-component sealant during which tooling is possible. (ASTM C 717-07a)

tooling, n
In building construction , the act of compacting and contouring a sealant in a joint. (ASTM C717-07a)

transfer, n
In pressure sensitive tapes, normally refers to “adhesive transfer,” but sometimes referring to any tape component which moves from its proper place to some other position during either unwind or removal.

transparency, n
The ability of a tape to allow trans­mission of light. A tape is rated as transparent if 10-point type can be easily read when the tape is applied directly over it.

transverse joint, n
A joint perpendicular to the direction of traffic in a highway pavement.

twisting, n
In pressure-sensitive tapes, the curling around the length-wise axis of a length of tape which has been unwound from the roll and allowed to hang freely.

two-component adhesive, n
An adhesive supplied in two parts which are mixed before application. Such adhesives usually cure at room temperature.

TxOver, n
Abbreviation for high temperature crossover.
Related Words  high temperature crossover (TxOver), n

 

U

ultimate adhesive, n
Maximum adhesion available from a pressure-sensitive adhesive, determined by the force necessary to remove a strip of tape from a surface after an extended period of time.

ultraviolet light (UV), n
Part of the light spectrum which can cause chemical changes in adhesive and sealant materials. Discussion— A UV curing adhesive requires no high temperatures, no solvents and no particularly complex equipment to be cured. All that is needed is exposure to UV light waves. Curing times range from as little as 1 second up to several minutes.

uniformity, n
The consistency of a single type of tape, either within a roll, or from roll to roll, or from lot to lot.

Unplasticized Vinyl (UPVC), n
A tough durable plastic film, differing from PVC principally in that UPVC is not very stretchy.

unwind (unrolling), n
Force required to remove tape from the roll.

unwind adhesion, n
See unwind (unrolling).
Related Words  unwind (unrolling), n

urea-formaldehyde adhesive, n
(1) an aqueous colloidal dispersion of urea-formaldehyde polymer which may contain modifiers and secondary binders to provide specific adhesive properties, (2) a type of adhesive, based on a dry urea-formaldehyde polymer and water. Discussion—A curing agent is commonly used with this type of adhesive. (ASTM D 907-06)

 

V

vacuum forming, n
A process in which an adherend is brought in intimate contact with a substrate to form an assembly by the evacuation of the surrounding air. (ASTM D 907-06)

vehicle, n
The carrier medium (liquid) for an adhesive material which improves its ease of application to adherends; solvent component of an adhesive.

vinyl (plasticized polyvinyl chloride, PVC), n
A tough durable plastic film having excellent resis­tance to oils, chemicals and many solvents. It has excel­lent abrasion-resistance and can be colored. Its high stretch is due to the addition of a plasticizer.

viscosity coefficient, n
The shearing stress tangentially applied that will induce a velocity gradient. A material has a viscosity of one poise when a shearing stress of one dyne per square centimeter produces a velocity gradient of (1 cm/s)/cm. (See also viscosity.) (ASTM D 907-06)
Related Words  viscosity, n

viscosity, n
Of a liquid, the resistance to flow expressed as the ratio of the applied shear stress to the resulting rate of shearing strain. (See Newtonian behavior, non-Newtonian behavior, and thixotropy.) (Compare consistency.) Discussion—The value for the viscosity of a liquid is the viscosity coefficient. (ASTM D 907-06)
Related Words  consistency, n; Newtonian behavior, n; non-Newtonian behavior, n; thixotropy (non-sagging), n

void, n
In pressure sensitive tapes, a bare uncoated area on either the adhesive or release coated side of the tape.

vulcanization, n
An irreversible chemical change (for example, cross-linking) in which a rubber compound becomes less plastic with greater elasticity, strength, stability, and chemical resistance over a greater range of temperatures. (ASTM D 907-06)

vulcanize, v
To subject to vulcanization. (ASTM D 907-06)

 

W

warm-setting adhesive, n
Synonym for intermediate-temperature-setting adhesive.
Related Words  intermediate-temperature-setting adhesive, n

warp, n
A significant variation from the original true, or plane surface. (ASTM D 907-06)

water absorption, n
The measure of the amount of water which will be soaked up by a tape and held.

water penetration rate (WPR), n
In pressure sensitive tapes, the measure of a tape’s ability to resist the passage of water through the tape itself expressed as g/100sq/in./24h.

water vapor transmission (WVT), n
In pressure sensitive tapes, the weight of water vapor transmission through a tape measured in gram/hundred square inches/24 hours.

weathering, accelerated, n
See accelerated aging.
Related Words  accelerated aging, n

weaving, n
In pressure sensitive tapes, a poorly wound roll of tape in which the individual layers of tape are not in alignment with the other layers.

webbing, n
(1) phenomenon that occurs when an adhesive is ejected from a spray gun as a series of web-like threads, (2) filaments or threads that may form when adhesive transfer surfaces are separated. (ASTM D 907-06)

wedge, n
In the field of adhesive technology, a tool made from a rigid material, tapering to a thin edge, used to separate adherends by force. (ASTM D 907-06)

wet strength, n
See wet strength under bond strength.
Related Words  bond strength, n

wood failure, n
The rupturing of wood fibers in strength tests on bonded specimens, usually expressed as the percentage of the total area involved which shows such failure.
deep wood failure, n—failure that is invariably several to many cells away from the adhesive layer, in which the fracture path is strongly influenced by the grain angle and the growth-ring structure.
shallow wood failure, n—failure that is invariably within the first one or two layers of cells beyond the adhesive layer in which the fracture path is not influenced by the wood-grain angle or growth-ring structure. (ASTM D 907-06)

wood laminates, n
(See also laminate, n) n—an assembly made by joining layers of lumber with mechanical fastenings so that the grain of all laminations is essentially parallel.
glue-laminated wood, n—an assembly made by bonding layers of veneer or lumber with an adhesive so that the grain of all laminations is essentially parallel.
plywood, n— a panel generally flat built up of layers of veneer called plies, united under pressure by an adhesive to create a panel with the bond between the plies as strong as, or stronger than, the wood, and that has the following characteristics: (1) is constructed of an odd number of layers with grain of adjacent layers perpendicular, (2) with a layer consisting of either a single ply or two or more plies laminated with parallel grain direction, and (3) with outer layers and all odd numbered layers generally having the grain direction oriented parallel to the long dimension of the panel. Discussion— The odd number of layers with alternating grain direction equalizes strains, reduces splitting, and minimizes dimensional change and warping of the panel. (ASTM D 907-06)
Related Words  glue-laminated wood, n; laminate, n; plywood, n

wood veneer, n
A thin sheet of wood, generally within the thickness range from 0.01 to 0.25 in. (0.3 to 6.3 mm) to be used in a laminate. (ASTM D 907-06)

working life, n
The period of time during which an adhesive, after mixing with catalyst, solvent, or other compounding ingredients, remains suitable for use. (Synonym pot life.) (Compare storage life.) (ASTM D 907-06)
Related Words  pot life (working life), n; storage life, n

 

X

 

Y

yield strain, n
The strain below which a material acts in an elastic manner, and above which it begins to exhibit permanent deformation or flow. Discussion—If a force or stress applied to a material strains that material less than its yield strain, all of the energy absorbed in the deformation is recovered when the force or stress is removed. All points within the material return to their original positions, thus showing elastic behavior. If the material is deformed more than the yield strain, some permanent deformation (flow) occurs and the points within the material do not return to their original positions when the stress is removed. Part of the energy is consumed in the permanent deformation. (ASTM D 907-06)

yield stress, n
The stress (either normal or shear) at which a marked increase in deformation occurs without an increase in load. (Synonym yield value) (ASTM D 907-06)
Related Words  yield value, n

yield value, n
Synonym for yield stress.
Related Words  yield stress, n

 

Z