CPC C09J 183/04 (2013.01) [B32B 7/06 (2013.01); B32B 7/12 (2013.01); B32B 27/08 (2013.01); C08G 77/08 (2013.01); C08G 77/16 (2013.01); C08G 77/20 (2013.01); C08G 77/22 (2013.01); C08G 77/80 (2013.01); C09J 7/38 (2018.01); B32B 2457/20 (2013.01); C09J 2203/326 (2013.01); C09J 2301/162 (2020.08); C09J 2301/302 (2020.08)] | 13 Claims |
1. A pressure sensitive adhesive layer-forming organopolysiloxane composition, the composition comprising:
(A) a chain organopolysiloxane having alkenyl groups in numbers greater than 1 on average within the molecule;
(B) an organopolysiloxane resin, wherein the total content of hydroxyl groups and hydrolyzable groups with respect to all silicon atoms in the molecule is 9 mole % or less, and the weight average molecular weight (Mw) measured in terms of standard polystyrene by gel permeation chromatography (GPC) is less than 4500;
(C) an organohydrogenpolysiloxane having at least two Si—H bonds in the molecule; and
(D) an effective amount of a hydrosilylation reaction catalyst; and optionally
(A′) a chain organopolysiloxane which does not contain a carbon-carbon double bond-containing reactive group in the molecule;
wherein the mass ratio of component (B) to the sum of components (A) and (A′) is within a range of 0.9 to 1.8, and the shear storage elastic modulus G′ at −20° C. of a pressure sensitive adhesive layer obtained by curing the composition is within a range of 0.01 to 1.0 MPa.
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