Glass laminate with thin insert obscuration having superior strength and optical quality

Abstract

Black enamel frit obscurations are commonly printed on laminated and tempered automotive safety glazing where they serve to hide the adhesive used to bind the glazing to the automotive body and to protect the adhesive from ultraviolet radiation. However, frit has a number of drawbacks. Frit weakens the surface of the glass. It can create distortion in the glass due to thermal gradients. Printed frit obscurations are incompatible and cannot be used with many types of coatings. Standard frit blocks ion exchange and cannot be used with the chemical tempering process. In addition, while many types of frits are available for printing on soda-lime glass, there are very few, if any, for non-soda lime glass. As the market moves towards thinner and lighter glazing, non-soda lime glass types are finding increasing application in automotive glazing. These limitations are overcome by replacing the printed black obscuration with an obscuration formed from a thin sheet of plastic, which is integrated into the laminate. This results in a laminate having superior optical quality, higher strength and a lower probability of breakage as compared to a laminate with a black enamel frit obscuration.