PRESSURE-SENSITIVE ADHESIVE
Pressure-sensitive adhesive comprising at least one polyisobutylene, at least one (meth)acrylate polymer or copolymer, and optionally additives, the proportion of polyisobutylene being at least 10% by weight of the pressure-sensitive adhesive.
1 . A pressure-sensitive adhesive comprising at least one polyisobutylene, at least one (meth)acrylate polymer or copolymer, and optionally additives, the fraction of polyisobutylene in the pressure-sensitive adhesive being at least 10% by weight, based on the weight of the pressure-sensitive adhesive.
2 . The pressure-sensitive adhesive of claim 1 , wherein the amount of polyisobutylene in the pressure-sensitive adhesive is at least 25% by weight, based on the weight of the pressure-sensitive adhesive.
3 . The pressure-sensitive adhesive of claim 2 , wherein the amount of polyisobutylene in the pressure-sensitive adhesive is at least 45% by weight, based on the weight of the pressure-sensitive adhesive.
4 . The pressure-sensitive adhesive of claim 1 , wherein the amount of additives in the pressure-sensitive adhesive is between 0% and 10% by weight, based on the weight of the pressure-sensitive adhesive.
5 . The pressure-sensitive adhesive of claim 1 , wherein the weight ratio of polyisobutylene to (meth)acrylate polymer or copolymer is between 5:1 and 1:5, based on the total weight of polyisobutylene to poly(meth)acrylate polymer or copolymer in the pressure-sensitive adhesive.
6 . The pressure-sensitive adhesive of claim 5 , wherein the weight ratio of polyisobutylene to (meth)acrylate polymer or copolymer is between 2:1 and 1:2, based on the total weight of polyisobutylene to (meth)acrylate polymer or copolymer in the pressure-sensitive adhesive.
7 . The pressure-sensitive adhesive of claim 6 , wherein the weight ratio of polyisobutylene to (meth)acrylate polymer or copolymer is between 1.5:1 and 1:1.5, based on the total weight of polyisobutylene to (meth)acrylate polymer or copolymer in the pressure-sensitive adhesive.
8 . The pressure-sensitive adhesive of claim 1 , comprising based on the weight of the pressure-sensitive adhesive,
(a) 40% to 60% by weight of polyisobutylene;
(b) 60% to 40% by weight of (meth)acrylate polymer or copolymer; and
(c) 0% to 10% by weight of additives.
9 . The pressure-sensitive adhesive of claim 8 , comprising based on the weight of the pressure-sensitive adhesive,
(a) 45% to 55% by weight of polyisobutylene;
(b) 55% to 45% by weight of (meth)acrylate polymer or copolymer; and
(c) 0% to 5% by weight of additives.
10 . The pressure-sensitive adhesive of claim 9 , comprising based on the weight of the pressure-sensitive adhesive,
(a) 45% to 55% by weight of polyisobutylene;
(b) 55% to 45% by weight of (meth)acrylate polymer or copolymer; and
(c) 0% by weight of additives.
11 . The pressure-sensitive adhesive of of claim 1 cured by electron beam curing.
12 . The pressure-sensitive adhesive of claim 1 , wherein said polyisobutylene has a weight-average molecular weight of greater than or equal to 500 000.
13 . The pressure-sensitive adhesive of claim 12 , wherein said polyisobutylene has a weight-average molecular weight of greater than or equal to 800 000.
14 . The pressure-sensitive adhesive of claim 13 , wherein said polyisobutylene has a weight-average molecular weight of greater than or equal to 1 000 000.
15 . A method for producing the pressure-sensitive adhesive of following claim 1 , comprising the steps of
(a) providing the polyisobutylene, the (meth)acrylate polymer or copolymer, and optionally the additives; and
(b) mixing the components provided in step (a), to give a homogeneous mixture; and
(c) shaping the mixture obtained in step (b).
16 . The method of claim 15 , wherein step (c) comprises applying said mixture to a carrier and in the process shaping it to a layer.
17 . The method of claim 15 wherein the mixture is subjected to an electron beam treatment.
18 . The method of claim 17 , wherein the electron beam treatment is carried out subsequent to the shaping of the mixture.
19 . A pressure-sensitive adhesive tape comprising the pressure-sensitive adhesive of claim 1 .
20 . A masking tape comprising the pressure-sensitive adhesive of claim 1 .
21 . The method of claim 16 wherein the mixture is subjected to an electron beam treatment.