SELF-ADHESIVE COMPOSITION AND ITS USE

Abstract

A pressure-sensitive self-adhesive composition capable of compensating for substrate unevennesses comprises a base adhesive and an additive, wherein the additive is a microparticulate additive which is insoluble in the base adhesive, does not crosslink with the base adhesive and has a bulk density in the range from 0.05 g/cm3 to 0.25 g/cm3 and an averaged particle diameter in the micrometer range. Adhesive coatings and self-adhesive sheet structures formed from the pressure-sensitive self-adhesive composition are also disclosed.

Description

Claims

1. A pressure-sensitive self-adhesive composition that compensates for substrate unevenness and comprises a base adhesive and an additive, wherein the additive is a microparticulate additive which is insoluble in the base adhesive, does not crosslink with the base adhesive and has a bulk density in the range from 0.05 g/cm3 to 0.25 g/cm3 and an averaged particle diameter in the micrometer range.

2. Self-adhesive composition according to claim 1, wherein the microparticulate additive has a bulk density in the range from 0.05 g/cm3 to 0.15 g/cm3.

3. Self-adhesive composition according to claim 1, wherein at least 70% of the particles of the microparticulate additive have a diameter of 200 μm or less and also at least 50% of the particles of the microparticulate additive have a diameter of 80 μm or less.

4. Self-adhesive composition according to claim 3, wherein at least 70% of the particles of the micro-particulate additive have a diameter of 100 μm or less and also at least 50% of the particles of the microparticulate additive have a diameter of 80 μm or less.

5. Self-adhesive composition according to claim 1, wherein the self-adhesive composition comprises the microparticulate additive in a fraction of 50% by weight or less.

6. A method of forming an adhesive bond between a self-adhesive composition and a substrate and at the same time compensating for any substrate unevenness, said method comprising adhering to an uneven substrate a self-adhesive composition according to claim 1.

7. An adhesive coating comprising a pressure-sensitive self-adhesive composition according to claim 1, the self-adhesive composition being in layer form.

8. Adhesive coating according to claim 7, further comprising a first outer self-adhesive composition formed layerwise on a first side of the layer-form self-adhesive composition and covering said layer-form self-adhesive composition on one side.

9. Adhesive coating according to claim 8, further comprising a second outer self-adhesive composition formed layerwise on a second side of the layer-form self-adhesive composition and covering said layer-form self-adhesive composition on one side.

10. A self-adhesive sheet structure comprising a backing and an adhesive coating according to claim 7.

11. Sheet structure according to claim 10, wherein the layer-form self-adhesive composition has a layer thickness of 100 μm or more.

12. A method of coating a sheet structure comprising the steps of preparing the pressure-sensitive self-adhesive composition according to claim 1 by mixing the particulate additives with the base adhesive, followed by applying the resulting self-adhesive composition to a sheetlike backing, and aftertreating the resulting coated sheet structure.