Silicone pressure-sensitive adhesive compositions

Claim 1

A curable pressure sensitive adhesive (PSA) composition having improved quick stick properties consisting essentially of: (A) a silicone adhesive composition consisting essentially of: (i) about 45 to 75 percent of a resin copolymer consisting primarily of R 3 SiO 1/2 and SiO 4/2 units and containing up to 5 molar percent of R 2 SiO 2/2 and RSiO 3/2 units, wherein each R individually is hydrocarbon radical containing up to 6 carbon atoms and wherein there are from 0.6 to 0.9 R 3 SiO 1/2 units for every SiO 4/2 units and wherein the resin comprises from about 0.2% to about 5.0% by weight, based upon the total resin weight of hydroxy radicals, and (ii) about 25 to about 55 percent of a silicone polymer gum having the formula ##STR3## where each R" is independently selected from alkyl, alkenyl, phenyl, aryl or arylalkyl, R'" is either a hydrogen or R 11 , R' is either a hydroxy or R", wherein the sum x+y is a number sufficient to give silicone gum a viscosity of from about 800,000 cps to about 200,000,000 cps at 25° C., and the total solids weight of (A)(i) and (A)(ii) being 100 parts, and optionally (iii) an organic solvent; and (B) about 2 to bout 30 parts by weight, based on the weight of (A)(i) and (A)(ii) being 100 parts, of silicone fluid of the general formula R 1 R 2 2 Si(OSiR 1 2 ) m (OSiR 3 R 4 ) n OSiR 2 2 R 1 or copolymers comprising R 1 R 2 2 SiO 1/2 ,R 1 2 SiO 2/2 ,R 3 R 4 SiO 2/2 , or R 1 SiO 3/2 units, wherein each R 2 independently is an alkyl, aryl, or arylalkyl group having up to 10 carbon atoms; and wherein R 1 ,R 3 , and R 4 each having up to 10 carbon atoms and independently selected from alkyl, aryl, aryalkyl, alkaryl, hydroxy, hydroxyalkyl, allyl, hydrogen, epoxide-containing-aliphatic, cycloaliphatic, aromatic, amine, aminocarboxy, fully- or partially fluorinated alkyl, alkenyl or aryl, and wherein n+m is such that the viscosity of the fluid is between 35 and 100,000 cps at 25° C., wherein said fluid is compatible with said silicone adhesive composition (A).