Method for producing a self-adhesive
A method for producing a foamed thermally crosslinked mass system, wherein the mass system is foamed at a first temperature in a first step, and crosslinker substances are added to the mass system in a subsequent step at a second temperature lower than the first temperature, wherein the crosslinker substances are crosslinker substances for thermal crosslinking of the mass system.
1. A method for producing a self-adhesive, comprising:
foaming a mass system comprising unexpanded microballoons at a first temperature, thereby forming a foamed mass system;
mixing crosslinker substances into the foamed mass system at a second temperature, which is lower than the first temperature, thereby forming a blended mass system; and
shaping the blended mass system to form a layer, thereby forming a self-adhesive,
wherein the crosslinker substances are crosslinker substances for thermal crosslinking of the foamed mass system.
2. The method of claim 1 , wherein the first temperature is equal to or above an expansion temperature of the unexpanded microballoons and the second temperature is below the expansion temperature.
3. The method of claim 1 , wherein:
in a first mixing assembly expandable microballoons and optionally further additives are introduced into a first mass system, thereby forming a second mass system;
the second mass system is heated under superatmospheric pressure to a temperature which at least corresponds to, and is optionally higher than, an expansion temperature of the expandable microballoons under atmospheric pressure;
the expandable microballoons are expanded on emergence from the first mixing assembly, thereby forming a third mass system;
the third mass system is introduced into a second mixing assembly, whereby the third mass system is at a temperature below the expansion temperature of the unexpanded microballoons;
the crosslinker substances are added to the second mixing assembly, thereby forming a fourth mass system; and
the fourth mass system is shaped.
4. The method of claim 1 , wherein:
in a first mixing assembly expandable microballoons and optionally further additives are introduced into a first mass system, thereby forming a second mass system;
the first mixing assembly comprises a first mixing zone and a second mixing zone;
the second mass system is heated under superatmospheric pressure in the first mixing zone to a temperature which is equal to or higher than an expansion temperature of the expandable microballoons under atmospheric pressure, thereby forming a third mass system;
the third mass system is transferred from the first mixing zone into the second mixing zone;
the third mass system in the second mixing zone is at a temperature below the expansion temperature of the expandable microballoons;
the crosslinker substances are added during transfer of the third mass system to the second mixing zone and/or after transfer of the third mass system to the second mixing zone, thereby forming a fourth mass system; and
the fourth mass system is shaped.
5. The method of claim 1 , wherein the self-adhesive is applied to a web-form carrier or a release material.
6. The method of claim 1 , wherein thermal crosslinking takes place after shaping.
7. The method of claim 1 , wherein the foamed mass system is in a noncrosslinked state.
8. A self-adhesive produced by the method of claim 1 .
9. A self-adhesive for a single or double-sided self-adhesive tape comprising the self-adhesive of claim 8 .