EMULSIFIER-FREE COATING AGENT, MANUFACTURE AND USE THEREOF

摘要

27 Herberts Gesellschaft mit beschr?nkter Haftung : An emulsifier-free coating agent in the form of an aqueous emulsion, a method of producing it and use thereof. The resin component of the coating agent consists of: A) 30 to 70 wt.% of a polyester oligomer polyacrylate dilutable with water after neutralisation with bases and obtainable by radical polymerisation of 50 to 95 wt.% of one or more esters of unsaturated carboxylic acids with hydrophobic and hydrophilic components, in which a) the hydrophobic components are based on monomeric esters of unsaturated carboxylic acids with secondary OH groups, which can be present in a mixture with comonomers free from OH groups, and b) the hydrophilic components are based on monomeric esters of unsaturated carboxylic acids with primary OH groups and unsaturated monomers with COOH groups, which can be present in a mixture with comonomers free from OH groups, and the numerical ratio of primary to secondary OH groups originating from components b) and a) in the copolymer being 1 : 1.5 to 1 : 2.5, in 28 5 to 50 wt.% of one or more hydroxyfunctional polyester oligomers obtainable by polycondensation of one or more diols and/or polyols and one or more dicarboxylic acids and/or their derivatives, optionally with use of one or more monoalcohols and/or one or more monocarboxylic acids, with calculated molecular weight of 200 to 1000, a hydroxyl number of 100 to 600 and an acid number of 0 to 15, the monomers a) and b) being added in quantities such that the polyester oligomer polyacrylate has a hydroxyl number of 100 to 390 and an acid number of 16 to 50, and the percentages by weight in each case relating to the content of solids and adding up to 100 wt.%; and B) 70 to 30 wt.% of one or more polyisocyanates with free NCO groups, the percentages by weight of components A) and B) in each case relating to the solids content of the resins and adding up to 100 wt.%, and the ratio of OH groups in component A) to free NCO groups in component B) being between 0.5 : 1 and 2 : 1, and the coating agent also contains water and optionally one or more organic solvents, pigments, fillers and/or conventional lacquer auxiliary substances and additives.