| abstract |
The adhesive composition for polarizing plates according to the present invention is an adhesive composition in which an acrylic polymer, a tin compound having a dialkyl group and serving as a cross-linking accelerator and an isocyanate cross-linker are dissolved in an organic solvent, the acrylic polymer being formed by copolymerization of monomers containing an alkyl (meth)acrylate, a hydroxyl group containing monomer and/or a carboxyl group containing monomer, wherein preferably, a solution containing 30% by weight of the acrylic polymer which consitutes the adhesive composition, dissolved in 70% by weight of ethyl acetate has a viscosity in the range of 0.5 to 10.0 Pa·s measured at 23°C, and the acrylic polymer has a weight-average molecular weight in the range of 300,000 to 700,000, and wherein temporal changes in the gel fraction of an adhesive forming an adhesive layer formed by the application of the adhesive composition satisfy the following conditions: n(a) the gel fraction 10 hours after the formation of the adhesive layer is 30% or more, n(b) the difference in gel fraction between 10 hours and three days after the formation of the adhesive layer is 15% or less, and n(c) the difference in gel fraction between 24 hours and 30 days after the formation of the adhesive layer is 5% or less. |