Glossary
- Resource Centre
- Glossary
Abrasion resistance
The ability of a tape to withstand rubbing and friction and still function satisfactorily.
Accelerated ageing
When the deterioration of a tape from natural ageing is accelerated and simulated in the laboratory.
Accelerated weathering
An aspect of accelerated ageing; a tape is placed in a chamber and exposed to ultraviolet light, heat, and water whereby the effect of exposure to outdoor conditions on a tape can be measured.
AccuPlace
Automated pick and place equipment for placement of difficult to handle adhesive components. Find out more here.
Acetate cloth
A type of backing used in electrical insulation tapes. This backing offers excellent absorption of electrical insulation resins and varnishes. View acetate cloth tapes here.
Acetate film
A transparent film which is used for various reasons as a tape backing. Its primary characteristic is that it is more moisture resistant than cellophane.
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.
Acrylic/acrylate
Synthetic polymer with excellent ageing characteristics that can be used as a component adhesive.
Adhesion
Adhesion is the interaction that develops between two dissimilar bodies when they are in contact. At the molecular level, adhesion is based on physical and in some cases chemical bonding. The strength of adhesion depends on the type of adhesive. Pressure sensitive adhesives build up adhesion under light pressure. The ultimate bonding strength is reached after 24-72 hours. Read our tips on getting the optimum adhesion from your adhesive tape.
Adhesion build-up
An increase in the peel adhesion value of a pressure-sensitive tape after it has been allowed to adhere to the applied surface.
Adhesion to backing
The bond produced to the backing of the same tape or another tape backing.
Adhesion to skin
A study to determine the degree of adhesion to skin of medical tapes or adhesives for up to 96 hours. Additionally, the amount of residue remaining on the skin after the material removal is assessed. For more information go to our device attachment to skin and wound care pages.
Adhesive
Adhesives are polymer materials that are used to join dissimilar materials. Adhesives may be classified in many ways, e.g. by mode of application and setting, chemical composition, cost, and suitability for various adherents and end products. The term “pressure sensitive adhesive” (PSA) is used to describe adhesives that are permanently tacky in dry form at room temperature. The most common pressure sensitive adhesives are acrylics, natural rubber/resin, and synthetic rubber/thermoplastic rubber.
Adhesive failure
Adhesive failure describes the separation of adhesive either from backing or from the substrate. The other basic failure mechanism of an adhesive bond is “cohesive failure” which refers to a fracture in the middle of the bulk adhesive. Learn more in our guide to using adhesive tapes.
Adhesive residue
Adhesive which is pulled away from the tape and remains on the surface to which the tape was applied.
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.
Ageing resistance
Ageing resistance is the degree of reliable performance of the tape over time, under certain conditions. Depending on the adhesive system being used, adhesive tapes are often usable for permanent applications. This permanence is reflected by the resistance of the adhesive against ozone (O3), oxygen (O2), UV light, temperature, humidity, water and different kinds of chemicals. Generally acrylic adhesives are much better suited to withstand these environmental influences than rubber adhesives and can maintain their permanent, reliable functionality over many years.
Anchorage
The specific adhesion of a pressure sensitive adhesive to a face material or an anchor coat.
Backing
Materials which “carry” the adhesive. The backing also reinforces the adhesive tape and improves handling and processing properties. Most commonly used backing types are film backings (e.g. PET, PP, PVC, PE), paper based backings (e.g. non-woven, tissue), foam backings (e.g. PU, PE and PVC foams).
A specialty adhesive tape type is a transfer tape which has no backing. The adhesive is directly coated on the liner.
Backside
The uncoated side or side opposite the adhesive coating. For a double coated tape, the side in contact with the liner after unwinding.
Backsize
A material applied to the backside of a tape to provide a release surface or heat seal property.
Bisco™
Bisco™ is a high performance silicone foam offering characteristics such as high resistance to temperature extremes, UV and ozone, high resilience to mechanical fatigue and excellent compression-set and creep resistance. See our foam and rubber page here for more information.
Blocking
An undesired adhesion between touching layers of 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 a force is applied evenly and perpendicularly to the surface of a tape.
CAD
Stands for Computer Aided Design. It is the use of computer programmes to produce 2D or 3D graphical representations of physical objects. These programmes enable the user to perform calculations and analyse component design variants for determining an optimum shape and size for the final output. This minimises the requirement for tooling and physical prototypes at your component design stage. Parafix offer this capability in house, learn more here.
Caliper
Thickness of a tape, backing, or adhesive, usually measured in mils (1/1000 of an inch).
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.
Clean room
A clean room is an environment with a controlled level of dust and other contaminants. Parafix has a class 7 clean room; compliant with BS EN ISO 14644-1, for the manufacturing of automotive, electrical and healthcare components. Learn more here.
Closed side (adhesive)
The surface of the adhesive on a double sided tape, which normally remains in contact with the release liner on unwinding.
Closed side (liner)
Is the surface of a release liner, which normally remains in contact with the adhesive on unwinding.
Coated cloth
Fabric with a rubber or plastic back coating. Examples are insulation tapes (including glass cloth and acetate cloth) and medical tapes (nonwovens). Browse our range of single sided cloth tapes here.
Coating weight
The amount of a solution applied to a sheet in the tape making process. The units are usually grains per 24 square inches.
Cohesion
Cohesion describes the inner strength of the adhesive. It mainly determines the holding power (shear resistance) of the tape.
Cohesive failure
Cohesive failure leaves adhesive residue on both the PSA tape backing and the laminated surface, showing that the adhesive broke internally. Use an easy check with your finger: it sticks on both the substrate and the tape.
Cold flow
The tendency of a pressure-sensitive adhesive to act like a heavy viscous liquid over periods of time. Such phenomena as oozing and increases in adhesion 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 colour, particularly when exposed to light.
Composite film
Conditioning
The process of subjecting material to specific temperatures and relative humidity conditions for a stipulated period of time.
Conformability
The backing of an adhesive tape influences its ability to adhere to curved, rough or irregular surfaces. Conformable backings increase the contact area of adhesive and substrate. Foam backings are inherently conformable and can therefore compensate for surface irregularities between the two bonding substrates.
Converting
The operation of changing a jumbo roll of adhesive tape into a finished product by slitting, short roll winding and die-cutting. Parafix has over 40 years experience as a tape converting specialist; read more about our converting capabilities here.
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.
Corona treatment
This is the method to modify the surface of a substrate to provide better anchorage of the adhesive. Corona treatment is an atmospheric plasma treatment. It is applied to non polar/low energy surfaces to facilitate the anchorage of the adhesive.
Creep
The slow movement of the adhesive or backing under shear stress.
Crepe paper
Paper which has small regular folds in it giving it a higher stretch than a flat back paper of the same weight.
Cross-linking
The development of a three dimensional structure within an adhesive to improve cohesive strength, temperature, oil or solvent resistance.
Cure
To alter the properties of an adhesive by chemical reaction, which may be condensation, polymerisation, or vulcanisation. Usually accomplished by the action of heat and catalysts, alone or in combination, with or without pressure.
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 increase of length of a piece of tape after it has been stretched without breaking and allowed to recover.
Delamination
Where the liner separates from the tape.
Dielectric strength
The measure of the maximum voltage stress that a single layer of tape can withstand before dielectric failure occurs, the test being carried out under prescribed conditions.
Dimensional stability
Correlates with humidity of liners. Dimensional stability prevents the liner from showing an irregular surface or dimensional change due to absorption of moisture. Dimensionally stable liners are mainly:
- PE coated paper liners
- Film liners
Double coated
See double-sided tape.
Double faced
See double-sided tape.
Double sided tape
Comprised of a backing material coated with adhesive on both sides. Usually one adhesive layer is covered with a release liner (closed side) in order to wind the PSA tape in roll form. In double sided tape production the backing is often pre-treated with a primer to enable a maximum anchorage between backing and adhesive.
View our range of double sided materials here.
Dual Lock™
Dual Lock™ is a 3M™ reclosable fastening system that is up to 12 times stronger than regular hook and loop systems. They offer temporary and invisible fastening for various applications, such as those within point of sale, signage and transportation.
Dwell
The length of time a tape sample is allowed to remain in contact with any specific testing surface before the test begins.
Easy unwind treatment
See release coating.
Edge curl
The peeling back or lifting of the outer edge of a tape after application.
Elastic memory
A tendency of some tape backings to return to their original length after being elongated.
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 adherends may exhibit.
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 at break
The amount a tape has stretched lengthwise at the point of breaking. It is expressed as a percentage of the original unstretched length.
EMI/RFI shielding
Where electro-magnetic interference and radio frequency interference is shielded in electronic devices. This can be achieved using various materials, including copper and aluminium tapes. Learn more here.
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.
Faceside
The side of the backing on which the adhesive is coated. For a double-coated tape; the side first exposed after unwinding.
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. View our filament reinforced tapes here.
Film
Uniform, homogeneous, plastic webs. Learn more on our single sided film tape and medical grade film pages.
Fish eyes
Relatively small deformations (pockmarks) in the adhesive caused by the entrapment of air between layers in the roll. These are not an indication of a quality defect.
Flagging
A peeling away from the surface or tape backing of the end of a length of tape, particularly in a spiral wrap application.
Flame resistance
This is 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.
Flame treatment
Method for modifying the surface of a substrate to provide better anchorage of an adhesive to a non polar backing by flame.
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
The distortion of a roll of tape such that the layers no longer form a circle.
Foam
These are materials containing small holes (cells) distributed throughout the entire body. They can be either closed cell or open cell. Most common foams are:
- AC foam
- Ethylene-vinylacetate-foam (EVA)
- Polyurethane-foam (PU)
- Polyethylene-foam (PE)
Browse our foam materials here.
Gapping
An opening between layers within a roll.
Glass cloth tape
A high strength tape offering insulation and protection against high temperatures and/or flame. They also provide solvent and abrasion resistance. View our glass cloth insulating tapes here. We also offer acetate cloth tapes.
Glass transition temperature
The glass transition temperature (TG) is the temperature at which the adhesive becomes brittle. It is important that the application temperature is distinctly above the TG of the adhesive (e.g. resealable bags that are stored in the fridge or freezer as it can prevent a safe reclosure of the bag). Learn more about storing your adhesive tape here.
Gloss
The measure of the reflectiveness of a tape backing, generally expressed by such terms as glossy, low gloss, dull, etc. A more specific definition is on the Gardner scale which measures absorption of light reflected from a beam with a stated angle of incidence.
Guillotining
Converting equipment commonly used to laminate and sheet adhesive materials. Learn more here.
Hand tearability
Property of tapes which allows manual cutting or tearing without the use of additional equipment such as knife, scissors or dispenser. Both liner and backing must be tearable.
Hard adhesive
A term usually used to characterise highly cohesive adhesive tapes. Advantages (compared to soft adhesives) include:
- Higher holding power
- Withstands higher sustained loads
- Good temperature resistance
- Less edge picking
- Improved die- cuttability
Disadvantages include:
- Low initial tack and adhesion;requires higher contact pressure
- Not suited for rough surfaces
Heat activated adhesive
A type of adhesive that is rendered tacky by application of heat and forms a bond on cooling. Browse our heat activated films here.
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 liner release
When the tape release from the liner is difficult, or above the expected result.
High-speed unwind
Unwinding or dispensing of tapes at a relatively high speed, usually over 15 metres per minute.
Holding power (shear adhesion, shear resistance)
The ability of the adhesive to resist forces applied in the same plane as the tape.
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.
Humidity resistance
Moisture or even humidity can affect the performance of an adhesive, especially if applied under wet or very humid conditions. In this instance, the adhesive absorbs the humidity, which leads to reduced adhesion performance. This effect occurs especially with water-based acrylics, which should not be used under those conditions. In general an adhesive tape is humidity resistant when it resists contact with humid air or even water without negative effects on the adhesion properties. Humidity can also damage paper liners and lead to ‘bubbles’ on the surface of the tape. All acrylics have a good humidity resistance and filmic liners are more dimensionally stable than paper ones. Read our guide on the correct storage of your adhesive tape.
HVAC
Stands for ‘heating, ventilation and air conditioning’.
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 impacts, pulls, or shocks as may sometimes be encountered by packages in transit or portable devices. Our range of foam tapes and VHB tapes are ideal for impact absorption.
Insulating tape
Tapes which are used for electrical insulation. For more information, visit our electrical insulation tapes page.
Insulation resistance
The ability of tape to prevent the flow of electrical current across its surface of the backing. Electrical insulation materials can be viewed here.
Interleave
See release liner.
Interliner
See release liner.
IP rating
The IP in “IP rating” stands for “Ingress Protection”. The IP rating refers to the robustness of a product to ingress of moisture and dust. Any enclosure should have an IP rating that classifies the design relative to application needs.
Jumbo
A large roll of tape or backing which is wound up as the material emerges from the coater or treatment. It is later converted.
Kapton®
Kapton® is the brand name for a polyimide film produced by DuPont. Browse our non-adhesive electrical insulation materials here.
Key
The bond between the adhesive and the carrier or backing.
Key coat
See prime coat.
Key failure
Failure of an adhesive bond such that separation is at the interface of adhesive and carrier or backing.
Kiss cut
A type of die-cutting where the cutter is adjusted to only cut the material and leave the liner or backing untouched.
Kraft
A sulphate wood pulp paper.
LAB
Low adhesion backsize.
Label stock
Pressure sensitive materials which are usually printed, frequently die cut, furnished in roll or sheet form with an interleave, and intended for use as labels.
Laminate, lamination
A combination of two or more materials, which function as one backing on web. Learn more about laminating here.
Lap joint
A joint made by lapping one material over another to provide a mated area that can be joined with an adhesive.
Laser cutting
Utilising laser technology to cut material. Often used to cut small and complicated geometries and to produce samples without tooling. Learn about our laser cutting capabilities here.
Latent stain
A stain in a surface to which tape has been applied, which does not become noticeable until sometime after the tape is removed, usually after the surface has been exposed to sunlight or heat.
Lifting
A situation where a section of tape has pulled away from the surface to which it has been applied, even though no outside stress is applied.
Liner
Anti-adhesive material which covers the adhesive on a double sided tape and prevents the adhesive from sticking to itself. The liner is used as a protection aid during handling, processing and storage. Most commonly used liner types are:
- Paper liners (e.g. glassine paper, PE-coated paper, clay-coated paper)
- Film liners (e.g. PP, PET, PE)
Silicone is used as a release system to avoid adhesion between liner material and adhesive.
Low release liner
The tape release from the liner is easy, or below the expected result.
Melinex™
The brand name for a polyester film made by DuPont. Browse non-adhesive insulation materials here.
Memory
The ability of a fibre or tape to return to its original form after being stressed or elongated.
Metal foil
Thin flexible sheets of metal, such as aluminium, copper and lead used as tape backings because of their inherent properties such as weather resistance, electrical conductivity and reflectivity. Browse our single sided foil tapes here.
Migration
The molecular movement over a long period of time of an ingredient from one surface to another when both are in contact. Migration may occur between tape components and the surface to which applied. Some plastic films (e.g. PVC) contain plasticisers which are apt to migrate into the tape adhesive, causing the adhesive to soften. Other ingredients like foaming, vulcanisation, age-resistant agents used for flexible seals migrate into the tape and can compromise the bond.
MSI
One thousand square inches.
MVTR
The moisture vapour transmission rate; a measure of the rate of water vapour transmission through a pressure sensitive product usually measured in grams/square meter/24 hours.
Natural rubber
Component of adhesives, not inherently self-adhesive. Resins, so called “tackifiers” need to be added to achieve self adhesive properties.
Nomex®
Nomex® is the brand name for an inherently flame-resistant aramid fibre that is manufactured by DuPont. For more information visit our non-adhesive insulation materials page or view our full range of insulation tapes here.
Non-polar substrates
Critical surfaces to adhere to due to low surface energy. The lower the surface energy the lower the molecular attraction to the adhesive (adhesion). Typical materials are polyolefins such as PP and PE, but also PS, EVA and many powder painted surfaces. By surface pretreatment (e.g. corona treatment) the polarity can be modified to achieve higher surface energy and improved adhesion. Use of primers will also act as adhesion promoters.
Non-woven
Paper and polymer fibre based backing material for adhesive tapes.
Occlusive
To prevent moisture from passing through.
Off-core
Layers of tape are in correct alignment, but tape is displaced sideways on 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 at the edge of the tape, caused by “cold flow” of a soft adhesive.
Opacity, opaqueness
The ability of a tape to prevent the transmission of light.
Open side (adhesive)
The surface of the adhesive on a double sided tape which is exposed on normal unwinding or separation.