| abstract |
An ultraviolet curable silicone adhesive composition containing (A) an organopolysiloxane resin which contains (a) a R1 3SiO1 / 2 unit (R1 represents a monovalent hydrocarbon group) and (b) a SiO4 / 2 unit, the molar ratio of unit (a) to unit (b) being 0.6: 1 to 1.2: 1, (B) a linear or branched organopolysiloxane having a viscosity greater than 50 mPa · s but less than or equal to 500000 mPa · s, while having 1 to 4 groups represented by the formula (1) and / or (2) (R2 representing H or Me, a representing a number from 1 to 3 and the broken line representing a bonding hand which is bonded to Si) as Si-linked groups and the main chain being composed of repeating diorganosiloxane units, and (C) a reactive diluent which is composed of an organo (poly) siloxane which has a viscosity from 1 to 50 mPa · s, while having a group represented by the formula (3) (a being as defined above e the broken line representing a binding hand) at one end of the molecular chain or in a molecular side chain as a Si-linked group. The composition according to the invention is rapidly cured by means of exposure to ultraviolet light and exhibits good adhesion to a sheet-like substrate. |