Patent ID: 8033360

Claim:
An interlayer film for a laminated glass, which, comprises at least a pair of protection layers and a sound-insulating layer sandwiched between the pair of the protection layers, and which has a wedge shape as a cross-sectional shape, a wedge angle θ of 0.1 to 0.7 mrad, the maximum thickness of 2000 μm or thinner, and the minimum thickness of 400 μm or thicker, the minimum thickness of the sound-insulating layer being 20 μm or thicker, wherein the protection layer contains 25 to 55 parts by weight of a plasticizer to 100 parts by weight of a polyvinyl acetal resin having an acetylation degree of 3% by mole or lower, 3 to 4 carbon atoms of an acetal group, and an acetalization degree of 60 to 70% by mole, and wherein the sound-insulating layer contains 40-80 parts by weight of a plasticizer to 100 parts by weight of a polyvinyl acetal resin.