Laminated transparent polarizing glasses and method of making

A method for making a laminated transparent, polarizing glass article consisting essentially of the following steps:

• (a) forming parallel microgrooves in a surface of a support of inorganic or organic glass through gentle abrasion of said surface by brushing with a thick rotary disc of polyester foam impregnated with an abrasive selected from the group of ZrO.sub.2 and Al.sub.2 O.sub.3 suspended in water;
• (b) carefully washing said surface by first brushing with a thick rotary disc of polyester foam impregnated with water and thereafter spraying with water and then drying said surface;
• (c) stabilizing said support to a temperature of 30.degree. C. .+-.1.degree. C. and a humidity of 50%.+-.5%;
• (d) at said temperature and humidity depositing on said surface a mixture of three organic colorants corresponding to the three primary colors and exhibiting a nematic state to form a coating demonstrating polarizing properties and thereafter rotating said support in order to orient the organic molecules according to the pre-alignment generated previously through the parallel microgrooves and to dry said coating;
• (e) treating said polarizing coating with an aqueous solution of metal salts having an acid pH to produce an ionic diffusion in said surface with the formation of, with the organic molecules, a metal sulfonate which is insoluble in water to reduce the water solubility of said polarizing compound;
• (f) rinsing said polarizing coating and then drying;
• and
• (g) applying a continuous, optically transparent composite film consisting of a layer of thermoplastic polyurethane having adhesive properties and a layer of thermosetting polyurethane having anti-lacerating and self-healing properties to said polarizing coating by first subjecting it to moderate temperature and pressure conditions in order to insure a wrinkle-free and gradual spreading out and adherence of the film upon the polarizing coating, and then subjecting it to elevated temperature and pressure conditions to reinforce the mechanical bond between the film and the coating and to complete the cross linking of the composite film.