COATING MIXTURES

摘要

1,242,005. Coating. CHEMISCHE WERKE HULS A.G. 8 Nov., 1968 [9 Nov., 1967], No. 53015/68. Heading B2E. [Also in Division C3] Sheets or glass plates may be coated with a coating mixture comprising 60-90 wt. % of (a) a polyester containing free OH and COOH gps, and 40-10 wt. % of (b) a polymer and/or oligomer containing N-methylol and/or N-methylol-ether gps. The mixture is in solution. The coating is then baked to give a layer 40-60Ám thick. In polyester (a), the alcohol component (A) comprises 80-100 mol % unsubstituted saturated vic-diol and 20-0 mol % alkane or cycloalkane diols in which OH gps are separated by 3-8 C atoms and in which up to 2 of the non-terminal C atoms may be replaced by O atoms separated by # 2 C atoms; and the acid component (B) comprises 80-100 mol % hexahydroterephthalic acid in the cis- and/or trans-form and 20-0 mol % of one or more other cycloaliphatic, aromatic, and/or olefinically unsaturated aliphatic dicarboxylic acids, such aliphatic dicarboxylic acids having # 8 C atoms. Polyester (a) has means M.W. 300- 2500. The vic-diol may be ethane-, propane-, butane-, or cyclohexane-, 1,2-diol, and may be racemates, or in the cis- and/or transforms. The other diol may be propane-1,3-diol, butane- 1,3-diol, butane-1,4-diol, hexane-1,6-diol, 2,2- dimethylpropane-1,3-diol, or 1,4-bis-(hydroxymethyl)-cyclohexane; or ethers with 2 OH gps, e.g. dipropyleneglycol, diethyleneglycol or triethyleneglycol. Acid component (B) may comprise carbocydic-phthalic, isophthalic, hexahydrophthalic, tetrahydrophthalic, or hexahydroiso phthalic acids in cis- and/or transforms; saturated aliphatic:- succinic, glutaric, adipic, or suberic acids; unsaturated aliphatic:- maleic, fumaric, itaconic, or citraconic acids. Instead of free acids, anhydrides or dimethyl, diethyl, or dipropyl esters may be used. The acid no. of the polyester may be raised by reaction with maleic anhydride. N-methylol or N-methylol-ether-compound (b) may be reaction products of formaldehyde and melamine, urea, N,N'-ethylene urea, dicyandiamide, benzoquanamine and polymers having a copolymer structure in which an amide of anα-ethylenically unsaturated carboxylic acid, having an N- methylol and/or N-methylol ether gp, is incorporated by polymerization; aminoplasts modified with alcohols, aminoplast precursors, e.g. hexamethylol melamine, or in etherified form, e.g. hexamethoxymethylolmelamine, Solvents for the coating may be xylene, butanol, butyl acetate, 2-ethoxyethanol, 2-butoxyethanol, 2-ethoxyethyl acetate, or mixtures thereof. The mixtures may also include: pigments, e.g. TiO 2 , flow agents, other binders, e.g. epoxide resins, acidic cross-linking accelerators e.g. p-toluenesulphonic acid; and maleic anhydride to raise the acid no. of the polyester.