Ppg Industries, Inc.

Charles W Lewis

Joseph P Cherenko

Earl E Parker

This invention relates to the lamination of large glass sheets using plasticized interlayer material without the use of autoclaves. Excess liquid plasticizer is applied to the major surfaces of a sheet of plasticized interlayer material to soak the major surfaces at room temperature for sufficient soaking time to soften the surfaces so that the interlayer becomes more amenable to adhesion to glass sheets, but insufficient time to normalize the plasticizer content throughout the thickness of the plasticized sheet. The interlayer sheet is assembled between a pair of glass sheets and the excess plasticizer is removed by compressing the assembly before the soaking time is excessive and the plasticizer concentration can normalize throughout the thickness of the plasticized interlayer sheet. With the excess liquid plasticizer at the interfacial surfaces only, the assembly is subjected to a temperature range above room temperature and below the temperature at which the plasticizer develops a volatile product and a superatmospheric pressure not more than two atmospheres. This removes excess plasticizer from the interfacial surfaces so as to limit the increase in normalized plasticizer content and also permits the sheets to be laminated to one another.

Fabricating laminated safety glass without an autoclave

Safety glass is made by laminating to a ply of glass a saturated polyvinyl acetal film incorporating a photoinitiator. The exposed surface of the film is irradiated with ultraviolet light which activates the photoinitiator which in turn initiates crosslinking of the polymer. The polymer film retains its desirable mechanical and optical properties while the crosslinked surface has improved solvent-abrasion resistance.

Laminated windshield with improved innerlayer

Safety glass made by laminating to a ply of glass a polyvinyl acetal film incorporating a photoinitiator. The exposed surface of the film is irradiated with ultraviolet light which activates the photoinitiator which in turn initiates crosslinking of the polymer. The polymer film retains its desirable mechanical and optical properties while the crosslinked surface has improved solvent-abrasion resistant.

Safety glass is made by laminating to a ply of glass a polyurethane film incorporating a photoinitiator. The exposed surface of the film is irradiated with ultraviolet light which activates the photoinitiator which in turn initiates crosslinking of the polymer. The polymer film retains its desirable mechanical and optical properties while the crosslinked surface has improved solvent-abrasion resistant.

Laminated articles of at least one sheet of relatively rigid, transparent material, e.g., glass, and polyesterurethane sheet are described. Such laminates, e.g., a bilayer assembly of one glass sheet with an adhered sheet of polyesterurethane or a trilayer assembly of two glass sheets with an interlayer of polyesterurethane sheet, are useful in safety glass applications, e.g., automobile windshields, and automobile side and rear windows. The polyesterurethane is preferably the reaction product of a cycloaliphatic diisocyanate and a relatively low molecular weight hydroxy-terminated aliphatic polyester, e.g., the esterification product of an aliphatic dibasic acid and an aliphatic diol.

Growing community of inventors

Pittsburgh, PA, United States of America

Charles W Lewis