Patent ID: 8585941
Filing Date: 2013-11-19
Classification: G02B,Y10T

Abstract:
1. A method for making a light transmissive sheet, comprising: (a) providing a release paper; (b) coating a second layer onto the release paper, wherein the second layer at least contains 5 to 50 wt % of polyurethane resin, 0.05 to 15 wt % of a colorant, 40 to 75 wt % of methyl-ethyl ketone (MEK), 5 to 15 wt % of dimethylformamide (DMF), and 1 to 15 wt % of toluene (TOL), wherein a solid content of the polyurethane resin is 15 to 35 wt %; (c) drying the second layer; (d) coating a light transmissive intermediate layer onto the second layer, wherein the light transmissive intermediate layer at least contains 60 to 90 wt % of polyurethane resin, 0.05 to 15 wt % of a colorant, 1 to 10 wt % of MEK, 5 to 15 wt % of DMF, 1 to 15 wt % of TOL, 1 to 15 wt % of a crosslinker, and 1 to 5 wt % of an auxiliary agent, wherein a solid content of the polyurethane resin is higher than 60 wt %; (e) drying the light transmissive intermediate layer; (f) coating a first layer onto the light transmissive intermediate layer, wherein the first layer at least contains 5 to 50 wt % of polyurethane resin, 50 to 95 wt % of MEK, 5 to 15 wt % of DMF, and 1 to 15 wt % of TOL, wherein a solid content of the polyurethane resin is 15 to 35 wt %; (g) drying the first layer; (h) removing the release paper; and (i) partially removing the first layer or the second layer, so that at least one pattern is formed on the first layer or the second layer, and the at least one pattern penetrates the first layer or the second layer, so as to partially expose the light transmissive intermediate layer.