Abstract: A coating composition which results from hydrolyzing 35 to 70 weight percent tetraethyl orthosilicate and 60 to 20 weight percent of certain silane is useful for providing abrasion resisting coatings for plastics after curing. Optionally, up to 20 weight percent of a silane having a reactive polar site or, in the alternative, a small percentage of a surfactant may be used to provide a dyeable coated article.

Abstract: A coating composition prepared by simultaneously hydrolyzing 20 to 50 wt. % tetraethylorthosilicate, 37 to 60 wt. % of certain silanes and 15 to 35 wt. % formalin has good abrasion resistance and resistance to crazing on substrates having a high affinity for water as well as those with a low affinity for water.

Abstract: A coating composition which results from hydrolyzing 40 to 70 weight per cent tetraethyl orthosilicate and 60 to 20 weight per cent of certain silane is useful for providing abrasion resisting coatings for plastics after curing. Optionally, up to 20 weight percent of a silane having a reactive polar site or, in the alternative, a small percentage of a surfactant may be used to provide a dyeable coated article.

Abstract: Polymeric rods suitable for manufacturing contact lenses may be improved by casting the rod in Teflon or in a Teflon-coated tube. Contact lens materials containing NVP as a monomer are preferably cast in tubes made of Teflon or having Teflon coating on the interior surface. The rods thus cast are substantially free of strain, have a uniform diameter, a smooth, continous exterior surface and an absence of voids therein. When initial polymerization is conducted at a moderate temperature in a water bath, the mixture is polymerized homogeneously to provide superior uniformity.

Abstract: Lens material suitable for ophthalmological use including implantation in the eye as an intraocular lens and as an ultra thin contact lens. The lenses are fabricated of polymethylmethacrylate (hereinafter PMMA) which PMMA is characterized by its very high molecular weight and almost complete freedom from strain. The PMMA may optionally be lightly cross-linked. The lens material is characterized by good machinability, color uniformity, and optical quality. It is substantially strain free and free from warpage when fabricated into extremely thin lenses.