Patent ID: 7858683
Filing Date: 2010-12-28
Classification: B32B,C08K,C08L,Y10T

Abstract:
1. An interlayer film for a laminated glass which comprises a laminate of films each comprising a poly(vinyl butyral) resin acetalized with butyraldehyde and triethylene glycol di-2-ethylhexanoate as a plasticizer, and which shows a temperature dependence of loss tangent in which the lowest-temperature side maximum of loss tangent appears at 30° C. or lower when examined for dynamic viscoelasticity, and wherein the at least one constituent layer is such that the poly(vinyl butyral) resin contains a metal oxide microparticle having a heat ray-shielding function, at least one constituent layer is such that the cloud point of a solution prepared by dissolving 8 weight parts of the poly(vinyl butyral) resin in 100 weight parts of the plasticizer is not higher than 50° C., and wherein the amount of the plasticizer relative to 100 weight parts of the poly(vinyl butyral) resin is larger in at least one constituent layer than that in the other layer or layers by not less than 5 weight parts; and in which at least one constituent layer comprises a poly(vinyl butyral) resin (C) derived from a poly(vinyl alcohol) resin which is a blend of a poly(vinyl alcohol) resin (A) and a poly(vinyl alcohol) resin (B), and the plasticizer, the difference in the average polymerization degree between said poly(vinyl alcohol) resin (A) and poly(vinyl alcohol) resin (B) being not less than 500.