Glossary of Terms
We bring you the brief explanation of some basic and/or less frequent terms related to PSA systems, Polymers, and Adhesive bonding:
| About polymers | ||
| ABS: | acrylonitril-butadiene-styrene (terpolymer) | |
| CR: | chloroprene rubber | |
| EPDM: | ethylene-propelene-diene (terpolymer) | |
| NR: | natural rubber | |
| PA: | polyamide | |
| PC: | polycarbonate | |
| PCTFE: | polychlortrifluoethylene | |
| PE: | polyethylene | |
| PET (PETP): | polyester (polyetheleneterephthalate) | |
| PI: | polyimide | |
| PMMA: | polymethylmethacrylate | |
| PP: | polypropylene | |
| PS: | polystyrene | |
| PTFE: | polytetrafluorethylene | |
| PUR: | polyurethane | |
| PVC: | polyvinylchloride | |
| PVDC: | polyvinylidenechloride | |
| SBR: | styrene-butadiene rubber | |
| SI: | silicon | |
| Glass Temperature (=Tg) | When the polymers are used at the temperature above Tg, they are soft and elastic, when used below Tg, they are hard and glassy. The are exclusions because of the cristallinity and other reasons. The values of Tg (in degK, 0 degC = 273 degK) for the most common polymers: NR/201, PE/148, PET/342, PMMA/378, PP/265, PS/368, PTFE/390, PVC/352, SI/146 | |
| Mr Horace Day | Is considered to be the inventor of PSA tapes. His USA patent no. 3965 is from the year 1845 | |
| Surface tension (=γ) | The lower the value of γ, the more diffult is to create an adhesive bond to the relevant (solid) polymer. The values (in mN/m) of γ for the most frequent polymers: EPDM/34,5, CR/43, NR/32, PE/36, PET/ ?, PC/44, PMMA/41, PP/30, PS/ PTFE/24, PVC/42, SI/21 Cellulose/42, Starch/39, Wool/45 | |
| About PSA Systems | ||
| Adhesive | A substance capable of bonding materials together by surface attachment | |
| Backings | A material, to which the adhesive is applied (coated and/or bonded) | |
| Carrier | Sometimes used to refer to the backing, particularly in double sided PSA tapes | |
| Labels stock | Pressure sensitive materials that are usually printed, frequaently die-cut, furnished in roll or sheet from with a liner, and intended for use as labels | |
| Pressure-sensitive adhesive | A category of adhesives, which in dry form adheres to the variety of surfaces | |
| Protective foil | A foil to protect the surface from abrasion, UV light, moisture, chemicals or their combination | |
| PSA label | A combination of face material, pressure sensitive adhesive and release liner, die cut into various shapes | |
| PSA system | The PSA tape and/or the PSA label and/or the converted PSA tape | |
| PSA tape | A combination of a pressure-sensitive adhesive and a backing | |
| Release Liner | A web or sheet material covering the adhesive side of a tape. (It is removed prior to application). | |
| Transfer tape | A PSA unsupported applied to a two-sided release liner | |
| About bonding with PSA Systems | ||
| Adherend | The surface to be bonded by adhesive | |
| Adhesion | A bond produced between a pressure sensitive adhesive and a surface | |
| Adhesion build-up | An increase in the peel adhesion value of a PSA tape after it has been allowe4d to dwellk to the applied surface | |
| Cohesion | The ability of the adhesive to resist splitting | |
| Peel strength | The force required to move the PSA tape from the standard test panel under the specified conditions (after the PSA tape is bonded to the said panel under the specified conditions) | |
| Shear strength | The internal or cohesive strength of the adhesive (The shear adhesion is typically measured as a time needed to slide the PSA system from the standard surface in a direction parallel to the said surface) | |
| Shelf-life | The period of time during which the product can be stored under specified conditions and still remain suitable for use | |
| Tack | The capability of an adhesive to stick to the surface (Tack is measured by various methods) | |
| Tensile strength | The force required to breake a piece of tape by pulling on opposite ends of the piece | |
| Ultimate adhesion | The maximum adhesion of PSA (measured as the force to remove the PSA tape from the surface after an extended period of time) | |
| Unwind adhesion | The force required to move the tape from the roll under specified conditions | |