Abstract: A tintable coating is applied to a transparent substrate such as a polycarbonate lens. The coating is made from a coating solution of (1) a further curable organopolysiloxane preferably made by hydrolyzing methacryloxytrimethoxy silane and vinyl triethoxy silane with phenylphosphonic acid, and an (2) organic solvent for the organopolysiloxane. The coating is cured, and azo dye applied to the cured coating, and the coating heated to provide a highly tinted coating without sacrificing scratch resistance.

Abstract: A tintable coating is applied to a transparent substrate such as a polycarbonate lens. The coating is made from a coating solution of (1) a further curable organopolysiloxane preferably made by hydrolyzing ethyl ortho silicate with methacryloxytrimethoxy silane and/or vinyltriethoxy silane with phenylphosphonic acid, and an (2) organic solvent for the organopolysiloxane. The coating is cured, an azo dye applied to the cured coating to provide a highly tinted coating without sacrificing scratch resistance. The cured coating can be tinted with an improved tinting speed and the resultant cured tinted coating has improved abrasion resistance.

Abstract: A method for producing solventless liquid organopolysiloxanes is disclosed. The method involves hydrolyzing an organo silicon composition comprising at least one compound having the general formulaY.sub.(4-n) Si(OR).sub.nwhere Y is phenyl or a primary or secondary alkyl group having from one to four carbon atoms, R is an alkyl group having from one to three carbon atoms, and n is an integer from one to four, and wherein the ratio of OR groups to silicon atoms in the composition is from 2.3:1 to 3.1:1. The products of hydrolysis are then heated to cause substantial siloxane formation by condensation and to distill water and alcohol by-products. Heating is continued until the water content of the resulting siloxane composition is less than 1 percent. The purity of the organo silicon composition, the amount of water used for hydrolysis, the amount of acid present during hydrolysis, and the heating of the organopolysiloxane are so controlled that the solventless organopolysiloxane has a viscosity at 25.degree. C.

Abstract: A process for forming organopolysiloxanes from trialkoxysilanes and the resulting resinous products are disclosed, characterized in that the organopolysiloxane resins have increased hardness when hydrolysis and condensation of the trialkoxysilanes are carried out in aqueous solution acidified by formic acid and at a relatively high strength previously regarded as inoperative. The formic acid, for example, may be present in an amount greater than 700 ppm. After hydrolysis of the trialkoxysilane, the resulting silonetriol is condensed to form the organopolysiloxane.