ABRASION RESISTANCE
The ability of a tape to withstand rubbing and still function satisfactorily.

ACCELERATED AGING
A means whereby the deterioration of a tape encountered in natural aging may be accelerated and reproduced in the laboratory.

ACCELERATED WEATHERING (weathering)
A means whereby the deterioration caused by outdoor exposure may be accelerated and reproduced in the laboratory.

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

ADHESION
A bond produced between a pressure sensitive adhesive and a surface.

ADHESION BUILD-UP
An increase in the peel adhesion value of a pressure sensitive tape after it has been allowed to dwell to the applied surface.

ADHESION TO BACKING
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.

ADHESIVE
Any material that will usefully hold two or more objects together solely by intimate surface contact.

ADHESIVE DEPOSIT
Adhesive that is pulled away from the tape and remains on the surface to which the tape was applied.

ADHESIVE MASS
Sometimes used as another name for the adhesive.

ADHESIVE RESIDUE
See Adhesive Deposit.

ADHESIVE TRANSFER
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.

AIR BUBBLES
Trapped air between the material and the liner. Trapped air will cause distortion in the material.

ANGLE CUTS
The edges of the part should be perpendicular to the top and bottom of the part.

ASTM
American Society for Testing and Materials. The ASTM develops standards on characteristics and performance of materials.

BACKING
A relatively thin, flexible material to which the adhesive is applied. Theoretically, any material that is reasonably flat, relatively thin and flexible could be used as a tape backing.

BACK SLIT
The product to be die cut is threaded into the machine with the side to be back slit towards the die. The die blade(s) cut through the liner and slightly into the material, but do not cut completely through the material.

BLEACHING
An erroneous term used to denote a condition of the surface under a tape that has remained the original surface color while the surrounding exposed area has discolored.

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

BLOWHOLES
Cavities in the material from the supplier. Acceptance criteria - the size of the hole must be under .063" in diameter unless otherwise specified.

BOND
The ability of the material to adhere to the adhesive system.

BURSTING STRENGTH
The ability of a tape to resist damage when force is applied evenly perpendicular to the surface of the tape.

CARRIER
Sometimes used to refer to the backing material particularly in double-faced tapes.

CHILL ROLLER
A device to cool the adhesive after it has been coated to a material. It also prevents adhesive from sticking to the drive rollers.

CLOSED CELL
A flexible, cellular material consisting of a non-interconnecting cell structure.

COHESION (cohesive strength, internal bond)
The ability of the adhesive to resist splitting. Good cohesion is necessary for clean removal.

COLD FLOW
The tendency of a pressure sensitive adhesive to act like a heavy viscous liquid over long periods of time. Such phenomena, as oozing and increases in adhesion, are the result of this characteristic.

COLOR
· The particular color of a tape when looking at the backing regardless of the color of the adhesive.
· Any deviation in color from the standard.

COLOR STABILITY
The ability of a tape to retain its original color particularly when exposed to light.

COMPRESSION DEFLECTION
PSI required to compress a given material a stated percentage of its original thickness.

COMPRESSION SET
The amount of permanent set a sample has after being compressed a stated amount, at a specific temperature, for a given amount of time and recovery period.

CONCAVITY
The wall of the part curves inwards.

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

CONFUSION
The transfer of adhesive from the tight side of the release liner to the easy side of the release liner in an adhesive system.

CONVEXITY
The wall of the part curves outwards.

CREEP
A slow movement of the adhesive or backing under stress.

CROSS-LINKED
The development of a 3-dimensional structure in an adhesive, which is activated normally by heat. An improvement in shear resistance, high temperature resistance and oil or solvent resistance will normally result.

CUPPING
A slight U-shaped deformation of the tape (at right angles to the length) which usually appears after unwind tension is relaxed.

CURED
See Cross-Linked.

CURLING
The tendency of a tape to curl back on itself when unwound from the roll and allowed to hang from the roll.

DEAD STRETCH
The net increase in length after tape has been elongated 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 or the separation between filaments and backing of a filament-reinforced tape.

DENSITY
A material's weight per unit volume.

DIE CUT OPTIONS
· KISS CUT - parts are die cut to the release liner without cutting through the liner. Each part must separate cleanly from the other parts and the liner.

· INDIVIDUAL PIECES - parts are die cut completely through the release liner. Each part must separate cleanly from the other parts and the liner.

· PADS - parts are die cut in a combination. Each part must separate cleanly from the other parts and the liner.

DIELECTRIC STRENGTH
The voltage a tape will withstand without allowing passage of the current through it.

DOUBLE COATED
The adhesive is applied on both sides of the backing which serves principally as a carrier for the adhesive.

DUROMETER
A meter used for measuring the hardness of cellular materials. The Shore 00 scale measures the hardness of sponge.

EDGE CURL
The peeling back or lifting of the outer edge of a tape after application. See Cupping.

EDGE SEAL
Material and liner are sealed together at the cut edge during the die cutting or slitting process preventing the liner from releasing from the material.

ELASTIC MEMORY
A tendency of some tape backings to attempt to return to original length after being elongated.

ELECTROLYTIC CORROSION FACTOR
A measure of the tape's corrosive effect on a copper conductor. This is particularly important factor in selection of tapes for use as electrical insulation.

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

EPDM
A rubber polymer consisting of ethylene, propylene and diene molecules. EPDM materials have ozone resistant properties.

FALL-OFF
Tape pulls completely away from the surface to which applied and drops off.

FILAMENTS
Thin longitudinal "threads" of glass, polyester, nylon or other high-strength materials.

FILM
Uniform, homogeneous, non-fibrous synthetic webs.

FISHEYES
Relatively small deformations (pock marks) in the adhesive caused by the entrapment of air between layers in the roll. They are not an indication of a quality defect.

FLAGGING
A peeling away from the surface of the end of a length of tape, particularly in a spiral-wrap application.

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 continue to burn after flame is removed.

FLEXIBILITY
The ability of a tape to be bent or flexed freely.

FLUTING
Distortion of a roll of tape such that layers no longer form a circle.

FMVSS 302
A Motor Vehicle Specification for flame spread. The rate of flame travel down a test sample must be less than 4" per minute.

FOAM
A soft, cushiony material formed by creating bubbles in base material such as natural or synthetic rubbers or other elastomeric materials.

FOAM / LINER SEPARATION
Paper liner should remove from material without the liner tearing.

FOLDOVERS
Any material having the appearance of being twice as thick as the standard.

FREEZING
A hardening or crystalizing of the adhesive after application so that tape cannot be removed easily or cleanly.

GAGE BANDING
a The uneven profile of a master of material.

GAPOSIS / REVERSAL
Spaces (gaps) between the wraps of DK rolls. Gaposis is caused by a loose rewind of the material. The log turning in the wrong direction during baloney slicing causes reversal.

GAPPING
Openings between layers of tape within a roll.

GLOSS
An appearance characteristic of tape backings usually expressed by such terms as glossy low gloss matte, etc.

HEAT RESISTANCE
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.

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

HOT MELT (pressure sensitive adhesive)
A pressure sensitive adhesive applied to the backing in a hot molten form that cools to form a conventional pressure sensitive adhesive.

HYDROPHIILIC
Having affinity for water: dissolving in, absorbing, or mixing easily with water.

HYDROPHOBIC
Not compatible with water: will not absorb or mix with water.

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

INSULATION RESISTANCE
The ability of a tape to prevent the flow of current across its surface usually measured on the backing.

INSULATING TAPE
Normally refers to tape used for electrical insulation.

IRREGULAR CELL STRUCTURE
Any appearance of cell structure in the material that deviates from the standard.

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K-FACTOR
A measure of thermal conductivity or heat insulation. Lower values indicate a better insulating material.

KRAFT
A sulfate wood pulp paper. See Saturation.

LAMINATION
A combination of two or more similar or dissimilar materials that function as one backing for example acetate and tissue in acetate fiber tapes.

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

LIGHTNING BOLTS
Uneven slitting of material.

LOOSE CORES
DK material that is not firmly attached or rewound to the core.

MASS
Sometimes used as another name for the adhesive.

MIGRATION
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 that are apt to migrate into the tape adhesive causing the adhesive to soften.

MULTIPLE COMPONENT ADHESIVE
A pressure sensitive adhesive containing one or more elastomers combined with resins and other components that impart tack adhesion and other necessary properties.

NON-TOXIC
A material that is free of any toxic substances in its composition.

NON-WOVEN
A manufactured sheet web or batt of directionally or randomly oriented fibers bonded by friction and/or cohesion and/or adhesion excluding paper and products that are woven knitted tufted stitch bonded incorporating binding yarns or filaments or felted by wet milling.

NOTCHES
The notched portion of the part should easily separate from the scrap or other parts when removed in multiple directions without tearing the foam or liner.

OFF-CORE
Layers of tape are in correct alignment but tape is displaced sideways on core.

OOZING
A "squeezing out" of the adhesive from under the backing. If it occurs when the tape is in roll form the edges of the roll become tacky.

OPAQUENESS
The ability of a tape to prevent the transmission of light.

OPEN CELL
A flexible, cellular material consisting of an interconnecting cell structure.

PAPER FRACTURES
From a die cut part or a DK roll the liner will not release from the material without tearing.

PEEL ADHESION
The force per unit width required to break the bond between a tape and a surface when peeled back; usually at 180 degrees at a standard rate and condition.

PENETRATION RESISTANCE
The ability of a tape to resist slow puncture under pressure.

POLYETHYLENE
A tough, stretchy film having very good low-temperature characteristics.

POLYESTER
A strong film having good resistance to moisture solvents oil caustics and many other chemicals. It is usually transparent.

POLYPROPYLENE
A cousin of polyethylene with generally similar properties but stronger and having a higher temperature resistance.

PSA
Pressure Sensitive Adhesive.

PSI
Pounds per square inch.

PRESSURE SENSITIVE
A term commonly used to designate a distinct category of adhesive tapes and adhesives, which in dry (solvent-free) form are aggressively and permanently tacky at room temperature and firmly adhere to a variety of dissimilar surfaces upon mere contact without the need of more than finger or hand pressure. They require no activation by water, solvent or heat 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. fly-papers) 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 TAPE
A combination of a pressure sensitive adhesive and a backing.

PRIMING
Coating the backing on the adhesive side with a thin layer of adhesive-like material that serves as a bonding agent between the adhesive and the backing.

PRINTABILITY
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.

PRINTING
The pattern of a tape left on a surface after tape has been removed. Most apt to occur when tape is applied to a freshly painted surface that has not fully hardened.

QUICK STICK (tack finger tack initial adhesion wet grab)
The property of a pressure sensitive adhesive that allows it to adhere to a surface under very light pressure. It is determined by the ability of the adhesive to wet the surface contacted quickly.

RECOVERY
The difference between ultimate elongation and dead stretch.

REINFORCEMENTS
A material added to a tape to provide additional strength.

RELEASE COATING (easy unwind treatment)
A coating applied to the backing on the side opposite the adhesive that provides ease of unwind and prevents delamination or tearing.

RELEASE LINER
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.

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

SHEAR ADHESION
See Holding Power.

SHRINKAGE
Reduction in any dimension of a tape.

SILICONE
A unique polymer system that can be a very effective release coating or pressure sensitive adhesive capable of functioning effectively at extreme temperatures.

SINGLE FACED
The adhesive is applied to one side of the backing only. Most pressure sensitive tapes are of this type.

SKIN
Incomplete removal of skin layer on a skived product.

SLIP SHEET OR INTERLINER
A treated sheet used to cover the adhesive to facilitate handling.

SLIVERING
Tape tears or breaks into small pieces, either on unwind or removal from a surface.

SMOOTHNESS
The relative flatness of the tape backing.

STIFFNESS
The measure of a tape's flexibility and conformability.

STORAGE STABILITY (roll-aging resistance)
The ability of a tape to retain its original properties after storage.

STRINGINESS
A condition of the adhesive in which it feels very soft and mushy and on close examination relatively long "legs" or "strings" of adhesive can be pulled out of the adhesive.

SURFACE DEFECTS
The appearance of cuts, abrasions, air bubbles, indentations or any other obvious defect in the surface of a part.

TEAR RESISTANCE
The ability of a tape to resist tearing after a tear has been started by cutting or nicking of the edge.

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

TENSILE STRENGTH (breaking strength)
The force required to break a piece of tape by pulling on opposite ends of the piece.
· CROSS DIRECTION TENSILE
Tensile strength measured at right angles to the length.

· MACHINE DIRECTION TENSILE
Tensile strength measured parallel to the length of the tape. Unless otherwise specified, tensile strengths are measured in the machine direction.

· WET TENSILE
Tensile strength of tape that has been kept wet for a specified period of time. Measures ability of tape to function satisfactorily when exposed to moisture.

THERMAL CONDUCTIVITY
The measure of heat transmission through a cellular material. Determined by the base material, cell size, density and often water resistant properties.

THERMAL STABILITY
Percent of linear shrinkage when the material is exposed to a given high temperature for a given period of time.

THERMOPLASTIC ADHESIVES
Adhesives that become softer as temperature increases, regardless of the number of heating cycles to which they are exposed.

THERMOSETTING ADHESIVES
Adhesives that set up or harden on first exposure to heat and remain set regardless of subsequent temperature cycles.

THICKNESS (caliper gauge)
Distance from one surface of either a tape backing or adhesive to the other usually expressed in mils or thousandths of an inch. This is usually measured under slight pressure with a special gauge.

THICKNESS VARIATIONS
Obvious deviations in the standard thickness of the material.

TRANSFER
Normally refers to "adhesive transfer" but sometimes is said of any tape component that moves from its proper place to some other position during unwind or removal.

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

TWISTING
The curling around the lengthwise axis of a length of tape that has been unwound from the roll and allowed to hang freely.

UL-94
Underwriters Laboratory ratings for flame spread. Horizontal burn tests in which a flame is applied to the test sample for 60 seconds and removed. The UL-94 HFB rating states the test sample cannot have a burn rate exceeding one and a half inches per minute. The UL-94 HF1 rating states that sample specimens must self-extinguish within two seconds after flame removal and not drip any flaming particles.

ULTIMATE ADHESION
The 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.

UNWIND or UNWIND ADHESION (Unrolling)
The force required to remove tape from the roll.

VINYL or PLASTICIZED POLYVINYL CHLORIDE (PVC)
A tough, durable plastic film having excellent resistance to oils, chemicals and many solvents. It has excellent abrasion resistance. It also can be colored. Its high stretch is due to the addition of a plasticizer.

VOID
A bare, uncoated area on either the adhesive or release-coated side of the tape.

WATER ABSORPTION
The measure of the amount of water that will be soaked up by a tape and held.

WATER PENETRATION RATE (WPR)
The measure of a tape's ability to resist the passage of water through the tape itself.

WATER VAPOR TRANSMISSION (WVT)
The weight of water vapor allowed through a tape within a specified time period.

WEAVING
A poorly wound roll of tape in which the individual layers of tape are not in alignment with the other layers.

WEB
The width of any material going through a machine.

WICKING
A term referring to excellent liquid absorption properties.

WRINKLES
The appearance of wrinkles in the adhesive system or material.

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