Pressure Sensitive Adhesive Tape Glossary


Abrasion resistance - The ability of a tape to withstand rubbing and still function satisfactorily.

Acrylic polymer – A synthetic polymer with excellent ageing characteristics that can be used either as a single component adhesive or a coating or saturate, depending upon composition.

Adhesion - The state in which two surfaces are held together by interfacial forces.

Adhesion build up - An increase in the adhesion value of a pressure sensitive tape after it has been allowed to dwell on the substrate.

Adhesion to backing - The force required to remove a tape (in the same manner as peel adhesion) from its own backing to which it has been reapplied with a defined pressure after being removed from the roll.

Adhesive residue (deposit) - Adhesive, which is pulled away from the tape on removal and remains on the substrate.

Adhesive transfer - The conveyance of adhesive from its normal position on the tape backing to a surface to which the tape was attached, either during unwind or removal.

Anchorage - Specific adhesion of a pressure sensitive adhesive to a face material or an anchor coat.


Backing - The flexible supporting film, fabric, foil, or paper, to which a pressure sensitive adhesive is applied.

Backsize – An occlusive coating applied to the non-pressure sensitive side of a porous backing, such as paper, to provide a satisfactory surface that the pressure sensitive adhesive side can contact when the tape is wound into a roll.

Bleeding - Penetration through the tape of a coloring material (paint, etc.) onto the surface to which the tape is applied.

Blocking - Adhesion between the sheets of the plies of rolls of coated material, usually due to extreme conditions of pressure, temperature or humidity.

Breaking load - The force required to break a unit width of tape under prescribed conditions.
Bursting strength- The ability of a tape to resist damage when force is applied perpendicularly to the surface of the tape.


Caliper - The thickness (as of a sheet of paper) measured under specified conditions. See also Thickness.
Carrier - The base material onto which a pressure sensitive adhesive is applied, on both faces, to produce a double-sided tape.

Cellophane film - A thin transparent film manufactured from wood pulp.
Closed side (adhesive) - That surface of the adhesive on a double sided tape, which normally remains in contact with the release liner on unwinding.

Closed side (liner) - Is that surface of a release liner, which normally remains in contact with the adhesive on unwinding.

Cohesion (cohesive strength, internal bond) - The ability of the adhesive to resist shear stress and splitting. Good cohesion is necessary for clean removal.
Cohesive failure - Failure of an adhesive bond such that the separation is within the adhesive.

Cold Flow - The tendency of a pressure sensitive adhesive to act as a heavy viscous liquid over long periods of time. Such phenomena as oozing and increase in adhesion with time are the result of this characteristic.

Colour - Usually describes the colour of a tape when looking at the backing, regardless of the colour of the adhesive.
Colour stability - The ability of a tape to retain its original color, particularly when exposed to light.

- The process of subjecting material to specific temperatures and relative humidity conditions for a stipulated period of time.
Conformability - The ability of tape to fit snugly or make essentially complete contact with a surface or an irregularly shaped object without creasing or folding.

Core - The inner cylinder of cardboard or plastic on which the tape is wound.

Corona resistance - The ability of an elastomeric adhesive, coating, or sealer acting as an insulator to withstand the effects of high-voltage discharge. Indications of failure appear as surface cracks.
Creep - The slow movement of the adhesive or backing under shear stress.
Cross-linking - The developing of a three-dimensional molecular structure in an adhesive normally activated by heat or irradiation. An improvement in shear resistance, high temperature resistance and oil or solvent resistance will normally result.
Cure - To alter the properties of an adhesive by chemical reaction, which may be condensation, polymerization or vulcanization. This is usually accomplished by the action of heat and catalysts, alone or in combination, with or without pressure.
Curling- The tendency of paper by itself or in a laminate to bend or partly wrap around the axis of one of its dimensions.


Dead stretch - The increase of length of a piece of tape after it has been stretched without breaking and allowed to recover.

Delamination - 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; separation between filaments and backing of a filament reinforced tape; or separation of the adhesive from the backing.
Dielectric strength - The measure of the maximum voltage stress that a single layer of tape can withstand before dielectric failure occurs, with the test being carried out under prescribed conditions.
Dimensional stability - The property of a material that relates to the constancy of its dimensions, particularly in relation to external influences such as moisture or temperature.
Double coated - An adhesive application to both sides of a backing. 


Edge curl - The peeling back or lifting of the outer edge of a tape after application.

Edge lift - The tendency for the edge of an adhesive label to lift from a surface to which it has been adhered.
Elasticity - The extensible property of adhesive films or adhesive interfaces to contract and expand in such a manner as to overcome the differential contraction and expansion rates that the bonded adherents may exhibit.

Elastic memory - A tendency of some tape backings to attempt to return to their original length after being elongated.

Elastomer - An elastic, polymeric substance, such as natural or synthetic rubber.

Electrical strength - The voltage at which breakdown of the tape occurs under the prescribed conditions of test, divided by the distance apart of the two electrodes between which the voltage is applied.
Electrolytic corrosion factor - A measure of the tape’s corrosive effect on an electrical conductor, particularly copper. This is particularly important in the selection of tapes for electrical insulation.
Elongation (stretch, ultimate elongation)- The distance a tape will stretch in the machine or cross direction before breaking under controlled conditions, expressed as a percentage of original length. Elongation is not necessarily an indication of conformability. 


Face stock - Any paper, film, fabric, laminate, or foil material suitable for converting into pressure sensitive material stock. In the finished construction this web is bonded to the adhesive layer and becomes the functional part of the tape construction.
Fall-off - When a tape pulls completely from the surface to which it is applied and drops off.
Fatigue - A weakness resulting from stress created by repeated flexing or impact force upon the adhesive-adherend interface.
Filaments - Thin longitudinal threads of glass, polyester, Nylon or other high strength materials.

- Uniform, homogeneous, non-fibrous synthetic webs.

Fisheyes - Relatively small deformations (pockmarks) in the adhesive caused by the entrapment of air between layers in the roll. These are not a indication of a quality defect.

- A peeling away from the surface or tape backing of the end of a length of tape, particularly in a spiral wrap application.
Flaking - A condition sometimes occurring during removal of masking tape in which flakes or particles of paint flake away from the tape backing.
Flame resistance - The ability of a tape to withstand exposure to flame. Fireproof materials will not burn even when exposed to flame. Flame-resistant (fire-retardant, self-extinguishing) materials will burn when exposed to flame, but will not sustain the burn after the flame is removed.

Flatback - A term used to describe a smooth paper backing for a tape to distinguish it from crepe paper backings.
Flexibility - The ability of a tape to be freely bent or flexed during application, particularly applicable in low temperature use.

Fluting- Distortion of a roll of tape such that the layers no longer form a circle. 


Gapping - Openings between layers of tape within a finished roll.
Gloss- A light reflection characteristic of tape backings, usually expressed by such terms as glossy, low gloss, matte, etc. 


Heat resistance - The ability of a tape to withstand a specified temperature under well defined conditions.

Heat seal -  An adhesive film intended to be reactivated by the application of physical or chemical changes caused by exposure to high temperatures.
High-speed unwind - A term referring to the process of unwinding or dispensing of tapes at a relatively high rate of speed, usually over 15 meters / minute.
Holding power (shear adhesion, shear resistance) - The ability of a tape to resist static forces applied in the same plane as the backing. Usually expressed in a time required for a given weight and length of tape to shear free from a vertical panel.
Hot melt - (pressure sensitive adhesive) - A pressure sensitive adhesive applied to the backing in a hot molten form, which cools to form a conventional pressure sensitive adhesive.
Hygroscopic- A tendency of some materials to readily absorb moisture from the atmosphere. 


Impact resistance (shock resistance) - The ability of a tape to resist sudden shocks as may sometimes be encountered by packages in transit.

Insulating tape - Normally applies to tape used for electrical insulation.

Insulation resistance - The ability of tape to prevent the flow of electrical current across its surface, usually measured on the backing.

Interleave - See Release liner.

Interliner - See Release liner.

Internal bond - See Cohesion.


Key - The bond between the adhesive and the carrier or backing.

Key failure- Failure of an adhesive bond such that separation is at the interface of adhesive and carrier or backing.


Label stock - Pressure sensitive insulation materials furnished in roll or sheet form with liner that can be later printed, frequently die cut, and intended for use as labels.

Laminate, lamination - Combinations of two or more materials which function as one backing e.g. Polyurethane foam and Polyester film.
Lap joint - A joint made by lapping one material over another to provide a mated area that can be joined with an adhesive.
Latent stain - A stain in a surface to which tape has been applied, which does not become noticeable until some time after the tape is removed—usually after the surface has been exposed to sunlight or heat.
Lifting - Occurs when sections of tape lose contact with the surface to which the tape applied.

Liner - See Release liner.

Low tack tape- Used (often incorrectly) to describe a pressure sensitive tape which has low adhesion. 


Metal foil - Thin flexible sheets of metal, such as aluminum, copper and lead used as tape backings because of their inherent properties, such as weather resistance, electrical conductivity, reflectivity, etc.

Migration - The movement over a 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 substrate.
Moisture Vapour Transmission Rate- A measure of the rate of water vapor transmission through a pressure-sensitive product usually measured in grams / square meter / 24 hours. 


Non-oriented- A material that has yet to be stretched or expanded to it's maximum size.


Off-Core - A roll of tape in which the layers are in correct alignment, but the tape is displaced sideways on the core.
Offsetting - The movement of a component of a tape, usually the adhesive, from its backing; this transfer may occur during unwinding of tape, or on removal of the tape from a substrate.

Oozing - A "squeezing out" of the adhesive from under the backing. Occurrence when a tape is in a roll form causes the edges of the roll to become tacky.
Opacity - The ability of a tape to prevent the transmission of light.

Open side (adhesive) - That surface of the adhesive on a double sided tape which is exposed on normal unwinding or separation.

Open side (liner) - Is that surface of a release liner which is exposed on normal unwinding or separation.
Out-gassing- The release of volatile components under heat or vacuum. 


Pattern coated - Refers to the width and spacing arrangement of strips of adhesive laid down parallel to machine direction and across the width of pressure sensitive stock during its production.

Peaking - Large singular upheavals in the outer layers of a roll of tape.
Peel adhesion - The force per unit width required to break the bond between a pressure sensitive adhesive tape and the surface to which it has been applied when the tape is peeled back at a controlled angle at a standard rate and condition.

Permanent adhesion - An Adhesive that has been designed to remain permanently in position under the specified service conditions.

Pinholes - Very small defects in a tape, which may permit the passage of light, electricity or water vapour, the minute holes may be in the backing and/or the adhesive.

Plasticization - The softening of an adhesive when exposed to migrating plasticizers or oils.

Plasticised Plyvinylchloride - A tough durable plastic film having excellent resistance to oils, chemicals and many solvents. It has excellent abrasion resistance. It can also be coloured. Its high stretch is due to the addition of a plasticizer.

Polyester film - A strong film having good resistance to moisture, solvents, oils, caustics and many other chemicals. It is usually transparent.

Polyethylene film
- A similar film to polyethylene, but stronger and having a higher temperature resistance.

Polyvinylidene Chloride film - A usually very thin transparent film with excellent resistance to acids, water and organic solvents.

Pre-release - The unwanted separation of a tape from its release liner during unwinding.
Pressure sensitive - A term commonly used to designate a distinct category of adhesive tapes and adhesives which in dry form (solvent / water free) are aggressively and permanently tacky at room temperature, and that firmly adhere to a variety of dissimilar surfaces upon mere contact without the need of more than finger or hand pressure. These products 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 metal. They have sufficient cohesive holding power 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.
Pressure sensitive adhesive tape - Pressure sensitive adhesive tape can be defined as a continuous flexible strip of cloth, paper, metal, plastic or foam coated on one or both sides with a permanently tacky adhesive at room temperature that will adhere to a variety of surfaces with light pressure (finger pressure) with no phase change (liquid to solid) and usually in roll form. PSAs can be blends of natural or synthetic rubber and resin, acrylic, silicone or other polymer systems, with or without additives.

Prime coat- A coating on the adhesive side of the backing, which serves as a bonding agent between adhesive and backing.

Printability- The ability of a tape to accept and hold a printed legend, and especially to resist offsetting of the print when unwound from a roll. 


Quick stick (Finger tack, initial adhesion, wet grab) - See Tack


Reinforcement - A material, which strengthens the backing and/ or the adhesive.

Release coating - A coating applied to a tape backing to facilitate the unwinding of the tape.

Release liner - A web of sheet material used as a protective liner, which covers the adhesive side of the tape. It is removed prior to application. It is most frequently found on double- sided tapes and label stocks.
Release force - The measure of the force required to separate a unit width of pressure sensitive tape from a release coated surface at a controlled angle and speed.
Removal - The act of pulling tape away from the substrate.

Removable adhesive
- An adhesive that has been designed to allow subsequent removal, without damaging or contaminating the substrate under specified conditions.

Resistance to acids, alkalies - The ability of a tape to resist exposure to such conditions after application and to perform satisfactorily.

Resistance to oils, grease, solvents etc. - The ability of a tape to resist exposure to such conditions after application and to perform satisfactorily.

Rewinding - The operation of winding the webstock from the reel onto a core to produce rolls of the desired width, diameter, and tension.

Roll ageing resistance - See Storage stability.

Rope stock- A smooth paper made wholly or largely of hemp fiber for tensile strength. 


Saturation - Adding materials (saturant) to the backing for improvement of physical properties and resistance to various deleterious environments.

Self-seal - An adhesive joint that is accomplished by coating both adherend surfaces, and bringing them under pressure; an elastomeric adhesive (cohesive) used on envelope flaps, box closures, etc., whereby the adhesive film will bond only to itself.
Shear adhesion - The time required, under specified test conditions (surface area, weight load), to slide a standard area of pressure sensitive tape from a standard flat surface in a direction parallel to the surface. See Holding power.
Shear strength after solvent immersion - The force required to separate a bond by shear force after immersion in a typical varnish solvent under designated conditions.

Shock resistance - See Impact resistance.

Shrinkage - Reduction of any dimension of a tape.
Single faced - A tape to which a pressure sensitive adhesive is applied to only one side of the backing.
Slip sheet or Interliner -See Release liner.
Slivering - When the tape tears or breaks into small pieces, either on unwind or on removal from a surface.

Splitting - See Delamination.

Stain - A discoloration of the substrate.

Stain resistance - The ability of a tape to be applied to a substrate without discolouring the substrate.

Stiffness - The measure of a tape’s flexibility and conformability.

Storage stability 
- The ability of a tape to retain a specified level of its original properties after defined conditions and length of time of storage.

Subsequent adhesion - The force required to remove a unit width of pressure sensitive tape from a standard panel after it has been in contact with a release liner for a given period of time. This must be compared with the adhesion of the same tape that has not been in contact with the release liner to determine the degree of loss of adhesion.

Substrate - The surface to which a pressure sensitive tape is applied.
Surface energy (surface wetting ability) - The measure of surface tension in dynes. The lower the surface energy of a substrate, the more difficult it becomes for an adhesive or coating to wet out that surface.
Surface treating- Any method of treating a polyolefin so as to alter the surface and render it receptive to inks, paints, lacquers, and adhesives such as chemical, flame, and electronic oxidation. 


Tack - The property of a pressure sensitive adhesive that allows it to adhere to a surface under very slight pressure. It is determined by the ability of the adhesive to wet quickly the surface it contacts.
Tear resistance - The force required to propagate a tear in a tape in a given direction after the tear has been initiated.
Telescoping - A sideways sliding of the tape layers, one over another, such that the roll looks like a funnel or a telescope, usually occurring over a period of time.
Tensile strength (breaking strength) - The force required to break a unit width of tape by controlled pulling on opposite ends.

Thermoplastic - Softens on heating. Reverts to original state when cooled. This process may be repeated.

Thermosetting - Becomes firmer on heating and remains so on cooling. Thermosetting of adhesive improves solvent resistance and increases softening temperature.

Thickness (caliper, gauge) - The perpendicular distance from one surface of either a tape, backing or adhesive to the other, usually expressed in mils, thousandths of an inch, or millimeters. This is usually measured under controlled slight pressure with a special gauge.
Transfer - Normally refers to “adhesive transfer”, but sometimes said of any tape component which moves from its proper place to some other position during either unwind or removal.

Transfer tape - A pressure-sensitive adhesive unsupported applied to a two-side release coated liner.

Transparent- The ability of a tape to allow the 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. 


Ultimate adhesion - The maximum adhesion available from a pressuresensitive adhesive, determined from the force necessary to remove a strip of tape from a surface after an extended period of time.

Unplasticised vinyl - A tough durable plastic film made from polyvinyl chloride without the addition of plasticiser.
Unwind or Unwind adhesion- The force required to remove tape from a roll under prescribed conditions. 


Vinyl- An abused abbreviation applied indiscriminately to both PVC and UPVC. 


Water absorption - The measure of the amount of water which will be soaked up by a tape under stated conditions and be retained by it.

Water penetration rate (WPR) - The weight of water transmitted through a controlled area of tape under a specified time and conditions.
Water Vapour transmission rate (WVTR) -  The weight of water vapour allowed through a controlled area of tape within a specified time period and under controlled conditions.

Wet grab - See Tack.

Information above is prepared with the use of materials on Afera and PSTC websites.