Patent ID: 6903152

Claim:
An interlayer film for a laminated glass which comprises a laminate of films each comprising a poly(vinyl acetal) resin and at least one plasticizer selected from the group consisting of triethylene glycol di-2-ethylhexanoate, tetraethylene glycol di-2-ethylhexanoate, triethylene glycol di-n-heptanoate, and tetraethylene glycol di-n-hepanoate, 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, wherein at least one constituent layer is such that the poly(vinyl acetal) resin has an average polymerization degree of not less than 1,500, an acetalization degree of 60 to 85 mol % and an acetyl up content of 8 to 30 mol %, with the combined total of said acetalization degree and acetyl group content being not less than 75 mol %.