Adhesive film for polarizing plate, polarizing plate including the same and optical display including the same

摘要

An adhesive film for polarizing plates has a K value of about 0.2 to about 0.5, as calculated by Equation 1. A polarizing plate includes the adhesive film for polarizing plates. An optical display includes the polarizing plate. The adhesive films for polarizing plates according to embodiments of the invention suppress light leakage due to dimensional changes in the polarizing plates at high temperature and/or high humidity.
K=ΔG′×ΔR0  Equation 1

主权项

1. An acrylic adhesive film for polarizing plates, the acrylic adhesive film having a K value of about 0.2 to about 0.5, as calculated by Equation 1:
K=ΔG′×ΔR0  Equation 1 wherein ΔG′ is defined by Equation 2, and ΔR0 is defined by Equation 3;
ΔG′=G1−G2  Equation 2 wherein G1 is a storage modulus in MPa at 23° C. and G2 is a storage modulus in MPa at 85° C., as measured from a 500 μm thick stacked adhesive film for polarizing plates by temperature sweep testing under a strain of 5%, a normal force of 100 N and an angular frequency of 1 rad/sec while elevating temperature from 0° C. to 100° C. at a rate of 10° C./min using an advanced rheometry expansion system;
ΔR0=R01−R02  Equation 3 wherein R01 is retardation in nm at 85° C. at a wavelength of 590 nm, and R02 is retardation in nm at 23° C. at a wavelength of 590 nm, as measured from a 1 mm thick adhesive film for polarizing plates upon application of a stress of 125 mN/15 mm while elevating temperature from 0° C. to 100° C. at a rate of 10° C./min.