Patent ID: 6599630
Filing Date: 2003-07-29
Classification: B32B,Y10T

Abstract:
A glass/adhesive sheet laminate comprising at least two layers of glass and a sheet of plasticized polyvinylbutyral positioned therebetween, said polyvinylbutyral having incorporated therein as an adhesion control additive an alkali metal salt to provide a preselected level of adhesion between said layers of glass and said sheet of polyvinylbutyral wherein asymmetric adhesion is present between the layers of glass and adjoining surfaces of the sheet of polyvinylbutyral, and as a leveling agent a different metal salt in an amount to provide a concentration of cation from the different metal salt in the PVB interlayer of 0.03-1.35 meq/kg, said amount being sufficient to reduce asymmetric adhesion between the plasticized interlayer and the adjoining surfaces of glass.