Patent ID: 7442420
Filing Date: 2008-10-28
Classification: C09K,G02B,G02F,Y10T

Abstract:
1. A retardation film comprising a liquid crystalline compound layer wherein the aligned state of the liquid crystalline compound is stabilized by UV curing, a protective layer and a polymer film, characterized in that the protective layer comprising a cured product of a UV-curable resin composition consisting of a mixture selected from the group consisting of the following mixtures (a) to (l) and a photoinitiator and which has been rubbed on the liquid crystalline compound layer side thereof is inserted between the polymer film and the liquid crystalline compound layer over the entire area thereof and is in direct contact with the polymer film and the liquid crystalline compound layer to control or block the migration to the liquid crystalline compound layer of a material present in the polymer film and affecting the optical properties of the liquid crystalline compound layer by migrating to the liquid crystalline compound layer: (a) a mixture of the reaction product of an isocyanate having an isocyanurate ring with pentaerythritol triacrylate and the reaction product of bisphenol A diglycidyl ether with acrylic acid and tetrahydrofurfuryl acrylate; (b) a mixture of the reaction product of pentaerythritol triacrylate with isophorone diisocyanate and the reaction product of bisphenol A diglycidyl ether with acrylic acid and tetrahydrofurfuryl acrylate; (c) a mixture of pentaerythritol triacrylate and tetrahydrofurfuryl acrylate; (d) a mixture of pentaerythritol triacrylate and the reaction product of 1,6-hexanediol diglycidyl ether with acrylic acid and tetrahydrofurfuryl acrylate; (e) a mixture of pentaerythritol triacrylate and polyethylene glycol diacrylate and tetrahydrofurfuryl acrylate; (f) a mixture of pentaerythritol triacrylate and the reaction product of bisphenol A diglycidyl ether with acrylic acid and tetrahydrofurfuryl acrylate; (g) a mixture of the reaction product of an isocyanate having an isocyanurate ring with pentaerythritol triacrylate and the reaction product of 1,6-hexanediol diglycidyl ether with acrylic acid and tetrahydrofurfuryl acrylate; (h) a mixture of pentaerythritol triacrylate and the reaction product of 1,6-hexanediol diglycidyl ether with acrylic acid and acryloyl morpholine; (i) a mixture of pentaerythritol triacrylate and bis(acryloxyethyl) hydroxyethyl isocyanurate and tetrahydrofurfuryl acrylate; (j) a mixture of tris(acryloxyethyl) isocyanurate and tetrahydrofurfuryl acrylate; (k) a mixture of bis(acryloxyethyl) hydroxyethyl isocyanurate and tetrahydrofurfuryl acrylate; and (l) a mixture of tris(acryloxyethyl) isocyanurate and the reaction product of bisphenol A diglycidyl ether with acrylic acid and acryloyl morpholine.