| 摘要 |
1,211,279. Coating. VIANOVA KUNSTHARZ A.G. 24 May, 1968 [21 June, 1967], No. 25006/68. Addition to 1,182,521. Heading B2. [Also in Divisions C3 and C7] Metal surfaces are coated with compositions using as binders water soluble resins prepared by the following process: (A) a compound (I) containing more than one but not more than two epoxy groups per molecule is reacted with a precursor (II) of a heat reactive compound which contains at least one hydrogen atom capable of reacting with epoxy groups (e.g. a phenol or amine); (B) the product of (A) is reacted with an aldehyde or an aldehyde/ phenol or aldehyde/amine condensate to form a water-insoluble, epoxy free product; (C) the latter is then reacted with a polycarboxylic acid or anhydride; (D) finally the product of (C) is neutralised with an inorganic or organic nitrogen base. I may be obtained from a compound containing more than two epoxy groups by reaction with a compound containing an esterifiable carboxyl group, e.g. a monoester of a dicarboxylic acid. II may be a dihydroxy diphenyl alkane, e.g. 2,2-bis(4-hydroxyphenyl) propane, an aminotriazine, urea or an aminoplast forming derivative thereof, polycarboxylic acid anide or imide, e.g. containing units derived from (meth)acrylamide. A preferred polycarboxylic acid for use in step (C) is an adduct of an α-#-unsaturated dicarboxylic acid with a fatty acid or mixture of fatty acids. Preferred I a diglycidyl ethers of bisphenol A having M.W. 400-3000. The resultant coatings may be cross-linked by stoving. |
