| abstract |
The instant invention pertains to a method of producing silicone pressure sensitive adhesives wherein the method comprises (I) combining together (A) a benzene soluble, hydroxyl containing organopolysiloxane resin consisting essentially of R3SiO1/2 siloxane units and SiO4/2 siloxane units, wherein R is a monovalent radical selected from the group consisting of hydrocarbon and halogenated hydrocarbon radicals having from 1 to 10 carbon atoms; there being from 0.5 to 1.5 R3SiO1/2 units for every SiO4/2 units and there being 1.0 to 4 wt %, based on FTIR, hydroxyl functionality and (B) a hydroxyl containing polydiorganosiloxane having a viscosity of >/=100 mPa's and (C) a catalyst selected from the group consisting of a weak organic acid or metal salt thereof; and thereafter (II) heating the mixture of (A), (B) and (C) for a time sufficient to produce the silicone pressure sensitive adhesive. |