Interlayers for use in sound-insulating laminated glasses.

摘要

The invention provides an interlayer for use in sound-insulating laminated glasses which is in the form of a laminated film of two kinds of resin films (A) and (B) each comprising a polyvinyl acetal acetalized with an aldehyde having 6 to 10 carbon atoms for the film (A) or with an aldehyde having 1 to 4 carbon atoms for the film (B), or is in the form of a resin film (C) comprising a mixture of the two kinds of polyvinyl acetal resins. The invention mitigates the coincidence effect to prevent the reduction of TL value without impairing the basic characteristics required of laminated glasses permitting the interlayer to exhibit outstanding sound-insulating properties over a wide temperature range for a prolonged period of time.