Glossary
Abrasion resistance
Abrasion resistance is the resistance of an adhesive tape to rubbing or friction. Adhesive tapes are classified according to abrasion classes A (low abrasion resistance) to G (outstanding abrasion resistance for special application) in line with CTM 312.
Acrylic adhesive
Acrylic adhesive are made of polymerised acrylic acid esters. They can be mixed with resin to enhance tack. These adehesives are available as solutions, watery dispersions or as hot melt adhesives. Their special characteristics include high ageing, temperature and chemical resistance, good compatibility with cable insulations and high resistance to UV radiation and oxidation.
Adhesion
Adhesion describes the hold between the surface of the adhesive tape and the taped material.
Ahesive force
Adhesive force combines the terms adhesion and cohesion and describes the force that is necessary to remove an adhesive tape from a surface. Standardised laboratory tests per EN 1939 are conducted to achieve comparable values. A 20 mm - wide strip of adhesive tape is applied to a steel plate and rolled on with a steel roller. It is then pulled off a specified speed and at an angle of 180° and the force required to pull it off is measured in N/cm.
Ageing resistance
Adhesive tapes used in the automotive industry are subjected to various ageing tests (e.g. temperature endurance tests) to ascertain whether and how their properties change as a result.
Backing material
The backing material is the carrier material to which the adhesive is applied.
Breakdown voltage
The minimum voltage that makes an insulator act as a conductor. It is significant for electrical insulating tapes and is measured in kV/mm.
Cohesion
Cohesion describes the inner stability of the adhesive. Adhesives with low cohesion leave a residue on the substate when the adhesive tape is removed.
Combatibility
Ability of two or more materials to interact without impairing the performance of any one component. A good compatibility of the adhesive tape with the cable insulation is a necessity when the cables are being wound.
CTM 312
A recognized testing guideline (Coroplast Test Method) based on the previous LV (Leistungs-Vorschrift) published by German automotive manufactures for rating of wire harness tapes.
Dispersion adhesive
In dispersion adhesive, the adhesive polymer particles are finely dipersed in water. Most dispersion adhesives are solvent-free. Emulsifiers have to be added to stabilise the dispersion.
Elongation at break
The strain required to break the material. For adhesive tapes this is specified according to EN 14410 and it is started in %.
Hot-melt adhesive
A solvent free adhesive thath is applied hot. Both acrylic adhesives and synthetic rubber-based adhesives can be processed hot.
Initial tack
Pressure-sensitive adhesives bond on contact. This is called initial tack. Some adhesives, especially adhesives on a tutly or acrylate basis, only achieve maximum adhesion some hours or days after they have been applied.
Laminate
Different backing materials are joined inseraparably (laminated) whereby the combination to their respective properties results in a new back material.
Leak tightness
Leak tightness is a material´s barrier function against substances such as chemicals, moisture or gas.
Liner
Films and papers coated on one or both sides with silicone are used as liners for pressure-sensitive adhesives. The siliconization makes them adhesive-repellent, which prevents this unintentional bonding of the various layers.
μm (micron)
A micrometer or micron is one millionth of a meter or one thousandth of a millimetre (0.001 mm). It is used to measure the thickness of materials such as films.
N
Newton is a unit of a measure for force.
Non-woven
Textiles made of natural or man-made fibres without weaving. The non-woven´s internal stability is achieved by pressing under heat or by stitching the individual fibres.
Operating temperature
The operating temperature is the range of temperatures at wich the adhesive bond remains intact and has nothing to do with the processing temperature. Electrical insulating tapes are classified according to EN 60454 and wire harness tapes according to CTM 312
Polyamide (PA)
Depending on the carrier, adhesive tapes with a PA backing material exhibit high temperature and abrasion resistance. Adhesive tapes with PA textile or PA velour backing material possesss the highest level of abrasion resistance as defined by CTM 312.
Polyester (polyethylene terephthalate, PET)
PET films and fabrics have outstanding tensile strength and tearing resistance. They are extremely resistant to high temperatures, alkaline solutions, acids oils and many solvents. PET fabrics generally unite high abrasion resistance with good resistance to high temperatures and chemicals.
Polyethylene (polyethylene terephthalate, PET)
PE films are soft and elastic, with high leak tightness and low tensile strength. Polyethylene is solvent-resistant but sensitive to UV radiation. These films are used to make electrical insulating tapes and anti-corrosion tapes.
Polypropylen (PP)
PP films are halogen-free and their properties are comparable with those of PE films. Although they are slightly less flexible, they are more temperature-resistant and can be used as a substitute for PVC adhesive tapes.
Polyvinyl chloride (PVC)
PVC films have good ageing and UV resistance properties. That is why PVC adhesive tapes are often used for outdoor applications. Different quantities of plasticizer can be added to PVC to make it extremely flecible. PVC adhesive tapes are widely used as a electrical insulating tapes due to their flame-retardant properties and good dielectric breakdown values.
Pressure-sensitive adhesive
A permanently active adhesive that is widely used on adhesive tapes or labels. As the name indicatesm the adhesive is activated by pressure. Secure bonding of the adhesive strip is achieved by pressing it down firmly.
Primer
A primer improves adhesion on surfaces that make ahesion difficult. It is often applied as a solvent-containing coating
Processing temperature
The temperature at which adhesive tapes can be processed. A far as possible, however, they should be applied at ambient temperatures between +10°C and +30°C
Rubber-based adhesive
Rubber-based adhesive consist of natural or synthetic rubber with added resin and softeners to provide adhesive tack. These adhesives are available as solutions or hot-melt adhesives. They have high initial adhesion but limited resistance to chemicals, solvents and UV radiation. Rubber-based adhesives are less temperature- and plasticizer-resistant than acrylic adhesives.
Sd Value
The Sd value is the measurand of the water vapour permeability of a substance in comparison with air.
Shear resistance
Shear resistance is the bonding strength of an adhesive when it is pulled off parallel to the glued surface (0° angle). It is tested by applying a section of adhesive tape to the end of a vertical steel plate and attaching a weight to the other end. Shear resistance is measured either as the time until the bond breaks or the maximum weight that the adhesive can bear.
Shelf life
The time for which an adhesive tape can be stored without any notable impairment of performance. Adhesive tape can be stored without any notable impairment of performance. Adhesive tapes generally have a shelf life of at least 6 months.
Silicone
Silicone is made of chemically modified SiO2 (sand). It has an ahdesive-repellent surface and is thererfore used in relesase papers or films (liners)
Solvent-based adhesive
50% of the adhesive often consists of a mixture of different solvents that have to be applied as solvent-based adhesives. Adhesive tapes with these adhesives pften have a distinctive odour as a result of incomplete vapourisation of the solvents.
Sound dampening
The extend to which adhesive tapes dampen noise. Adhesive tapes are classified in sound-dampening classes A (low sound-dampening) to E (maximum sound-dampening) per CTM 312. It is measured in db(A).
Tack
A measure of the viscous flow of an adhesive that describes its stickness at minumum application pressure. Tack is measured in tests such as the "rolling ball test", in which a steel ball is rolled onto the adhesive surface. The distance that the ball rolls until it sticks to the tape frpm a ramp is measured. The shorter the distance, the higher the tack.
Tensile strength
The pull stress required to break a material. For adhesive tapes, tensile strength is determinied in accordance with EN 14410, and it is stated in N/cm.
Textiles
Textiles may be cloth, made of warp and weft, or non-wovens. Yarn and fibres are usually made of polyester, viscose or polymide.
Unwind force
The force that is necessary to unwind the adhesive tape from the roll. Unwind force is measured in N (Newton).
UV radiation
Ultra-violet radiation is component of sunlight that can cause chemical reactions. UV radiation can also be used for croll-linking to improve the stability of acrylates.