Abstract: A coating composition to improve the abrasion and scratch resistance of plastics such as polycarbonate, consisting essentially of about(A) 10-40% by weight of a partially hydrolyzed siloxane compound which is obtained by hydrolyzing in water at about 50.degree.-80.degree. C. over a period of about 1-12 hours at least one of(a) a hydrocarbon-trialkoxysilane of the formula R'Si(OR").sub.3 whereinR' is an alkyl group with 1 to 4 carbon atoms or a phenyl or vinyl group, andR" is an alkyl group with 1 to 4 carbon atoms,(b) a co-condensation product of (a) and about 1 to 40% by weight of a phenyl- or vinyl-trialkoxysilane, the alkoxy group containing 1 to 4 carbon atoms,(c) a co-condensation product of 1 mol of (a) and 0.05 to 1 mol of a tetraalkoxysilane, in which the alkoxy group contains 1 to 4 carbon atoms, and(d) a co-condensation product of 1 mol of (a) and 0.05 to 1 of a dialkyldialkoxysilane, in which the alkyl and alkoxy groups contain 1 to 4 carbon atoms.

Abstract: This invention relates to new ammonium salts of .alpha.-ketocarboxylic acids, to their use for the production of amines in situ by photochemical decomposition and to photochemically hardenable coating compositions containing these ammonium salts.

Abstract: The instant invention is directed to a process for the production of molded polyisocyanate-based foam products having a compact, light- and yellowing-resistant polyurethane-based top layer comprising the steps of:A. coating a mold with a liquid polyurethane-polyurea-based coating agent, containing a binder, which reacts to form a light- and yellowing-resistant top layer andB. introducing a foamable reaction mixture into said mold,wherein said binder comprises:(i) at least one isocyanate prepolymer having at least two exclusively aliphatically and/or cycloaliphatically bound isocyanate groups and(ii) a hardener mixture composed of water and primary polyamines, at least partly in aldimine- or ketimine-blocked form, which have aliphatically and/or cycloaliphatically bound amino groups.

Abstract: The present invention is concerned with a process for producing biuret polyisocyanates and the polyisocyanates so produced. These isocyanates are produced by the reaction of at least about a four fold molar excess of a diisocyanate having aliphatically bound isocyanate groups with amino alcohols having a particular structure at a temperature between about 90 and 200.degree. C. The amino alcohols contain at least three carbon atoms, have their hydroxyl and amino groups separated by at least two carbon atoms, and may contain urea, urethane, ether or amino bonds. The present invention is also concerned with a process for producing two component and one component moisture curing lacquers using the biuret polyisocyanates of the present invention and the lacquers so produced.

Abstract: This invention relates to a process for the production of new polyisocyanate mixtures containing blocked isocyanate groups, to binders containing these polyisocyanate mixtures and to the use of the new polyisocyanate mixtures as an isocyanate component in polyurethane stoving lacquers.