| abstract |
The pressure-sensitive adhesive composition for polarizing plates of the present invention is an acrylic polymer obtained by copolymerizing a (meth) acrylic acid alkyl ester with a monomer containing a hydroxyl group-containing monomer and / or a carboxyl group-containing monomer, a tin compound having a dialkyl group as a crosslinking accelerator, and an isocyanate crosslinking agent. It is an adhesive composition melt | dissolved in the organic solvent, The acrylic polymer which forms this adhesive composition; About the solution which melt | dissolved 30 weight% in ethyl acetate; 70 weight% ethyl acetate, the viscosity of this solution measured at 23 degreeC is 0.5-10.0. The aging change of the gel fraction of the adhesive which forms the adhesive layer obtained by apply | coating the adhesive composition which is Pa.s and the weight average molecular weight of this acrylic polymer in the range of 300,000-700,000 (a) gel fraction 10 hours after adhesive layer formation. 30% or more of this, and (b) difference of the gel fraction after 10 hours of adhesive layer formation and 3 days after formation is 15% or less, (c) point It is preferable that the difference of the gel fraction after 24 hours of formation of a complex layer and 30 days after formation satisfies the conditions of 5% or less.n n n Polarizing plate, pressure-sensitive adhesive, acrylic polymer, tin compound, isocyanate. |