Abstract: A process for the preparation of blocked polyisocyanates which comprises reacting a polyisocyanate with a cyclic amidine of the formula: ##STR1## wherein R are the same or different substituents selected from the group consisting of hydrogen, alkyl, cycloalkyl, aralkyl and aryl, and wherein either R' and R or two R' taken together form a cycloaliphatic ring, and wherein the reaction is carried out at temperatures of 0.degree.-150.degree. C. Polyisocyanates blocked with 6-membered ring bicyclic amidines.

Abstract: A process for the coating of glass surfaces with a transparent, duroplastic protective layer of more than 50 microns which comprises first treating the clean glass surface with an aqueous or alcoholic silane skim coat, drying the treated surface and then coating the dry surface with a paste of aliphatic or cycloaliphatic diisocyanates or mixtures thereof or the reaction products with water in the mole ratio of 2:.ltoreq.1 and a mixture of hydroxy-group-containing compounds consisting of40-80 wt. %, trifunctional, hydroxy-group-containing polyester polyols made of aliphatic or cycloaliphatic dicarboxylic acids or mixtures thereof and a mixture of triols, diols or tricarboxylic acids, with an average molecular weight of 300 to 1400,15-50 wt. % bifunctional, hydroxy-group-containing polyester polyols from aliphatic or cycloaliphatic dicarboxylic acids or mixtures thereof and diols, with an average molecular weight of 400 to 2000 and, if necessary,2.5-25 wt.

Abstract: Powdered, heat-hardenable coating materials with high storage stability and a grain size smaller than 0.25 mm based upon hydroxy-group-containing polyesters with melting points between 40.degree. and 120.degree. C., blocked polyisocyanates and optionally catalysts, wherein the coating material contains polyisocyanates blocked with cyclic amidines of the general formula ##STR1## wherein R=equal or different substituents selected from the group consisting of hydrogen, alkyl-, cycloalkyl-, aralkyl-, and alkyl radicals. A method for the production of the above mentioned coating materials and a process for coating substrates with these materials is also disclosed.

Abstract: A powdery polyurethane lacquer which comprises (a) a hydroxyl-group containing polyester resin with an OH number of 40-240 and (b) an .epsilon.-caprolactam-blocked polyisocyanate, selected from the group consisting of triisocyanatoisocyanurate of 3-isocyanatomethyl-3,5,5-trimethylcyclohexylisocyanate and mixtures of said triisocyanatoisocyanurate with monomeric or oligomeric 3-isocyanatomethyl-3,5,5-trimethyl-cyclohexylisocyanate; wherein the .epsilon.-caprolactam-blocked triisocyanatoisocyanurate has at least two blocked isocyanate groups and wherein the .epsilon.-caprolactam-polyisocyanate is present in an amount sufficient to cause hardening of said mixture of (a) and (b). The lacquer is especially useful for electrostatic coating of substrates.

Abstract: A method for the production of blocked isocyanate-and isocyanurate group-containing compounds which comprises:transforming a monomeric aliphatic or cycloaliphatic polyisocyanate or a mixture thereof into an intermediate mixture comprising an isocyanurate containing at least 2 free isocyanate groups; andblocking said intermediate isocyanurate mixture with dimethylketoxime at 50.degree.-120.degree. C.;wherein the amount of said dimethylketoxime is such that one equivalent of NCO group reacts with one equivalent of said dimethylketoxime.The mixtures of the present invention are particularly suited as co-catalysts for the anionic polymerization of epsilon-caprolactam, as well as hardeners for higher functional thermoplastic compounds which contain Zerewitinoff-active hydrogen atoms.

Abstract: Baking lacquers on the basis of a blend of hydroxy-group-containing polymers, blocked polyisocyanates and organic solvents which comprise40-70 wt. % hydroxy-group-containing polymers with hydroxy numbers between 40 and 240 and polyisocyanates blocked with cyclic amidines of the formula: ##STR1## wherein R are equal or different substituents selected from the group of hydrogen, alkyl-, cycloalkyl-, aralkyl- and aryl radicals, whereby the components are used in such amounts that 0.8 to 1.2 NCO-group equivalents are applied for each hydroxy group equivalent,0-2 wt. % cross-linking catalyst,30-60 wt. % organic solvent or solvent mixture, wherein the percentages of polymer, catalyst and solvent add up to 100. Pigments, colorants, flowing agents, gloss improvers, antioxidants and heat stabilizers may also be added. The lacquers are used for coil-coating lacquering in weather resistant single and double layer lacquering.

Abstract: A method for the coating and protection of a glass surface which comprises:treating the glass surface with an aqueous or an alcoholic solution of a silane in order to provide a skim coat thereon, drying the resulting silane-coated surface, coating the dried silane-coated surface with a paste comprising (1) an aliphatic or cycloaliphatic diisocyanate, a mixture thereof, or a reaction product thereof with water, wherein the mole ratio of said diisocyanate to water is 2:.ltoreq.1 and (2) a hydroxy-group containing polyester derived from a .omega.-hydroxy carboxylic acid or a lactone therefrom and a triol, wherein said acid or lactone contains at least 4 carbon atoms, and hardening the paste. Glass bottles coated by this a method are also described in this invention.

Abstract: A method for the coating of glass surfaces in order to prevent the scattering of glass particles upon bursting, with a transparent, duroplastic protective coat by depositing a paste of hydroxy group-containing 1,2-epoxy compounds with at least one 1,2-epoxide group in the molecule and a lower melting point of more than 40.degree. C. and hardening agents, and hardening the overlay at higher temperatures; which comprises first treating the clean glass surface with an aqueous or alcoholic silane skim coat, drying said surface if necessary and thereafter warming said surface to a temperature up to 120.degree. C.

Abstract: This invention relates to blocked isocyanates and to a method for making blocked isocyanates by blocking the isocyanate groups of a polyisocyanate, which may be chain extended, with a cyclic amidine compound of the formula ##STR1## where the R's are the same or different substituents inert to isocyanate groups.