GB1193357A - Resin for Electrodeposition and method for preparing the Resin - Google Patents

Abstract

1,193,357. Water-soluble resins from maleinized oil/rosin esters. SHINTO PAINT CO. Ltd. 22 Dec., 1967 [29 Dec., 1966], No. 58484/67. Heading C3R. [Also in Divisions C4 and C7] A resin for electrodeposition is prepared by mixing a drying or semi-drying oil or a corresponding fatty acid or ester thereof with 10-70 wt. per cent, based on said oil, acid or ester, of a resin acid or rosin, esterification of the mixture with at least 10% excess, over the carboxyl groups present, of a polyhydric alcohol to an acid number of 0-3, subjection of the resultant resin to reaction with maleic anhydride or fumaric acid, and neutralization of 50-100% of any free carboxyl groups in the product with a base, optionally having esterified 5-70% of the carboxyl groups initially present with a C 2-4 dihydric alcohol before the neutralization. Suitable oils are linseed, tung, safflower, perilla, hempseed, cottonseed, sesame, rapeseed, soybean, dehydrated castor and tall oils, and acids from these, and esters of these acids with glycerol, pentaerythritol, trimethylolpropane, trimethylolethane or ethylene or propylene glycol. Suitable polyhydric alcohols include ethylene glycol and the propylene and butylene glycols, hexylene glycol, glycerol, trimethylolpropane, trimethylolethane, pentaerythritol and epoxy resins of M.W. 250-500. Suitable C 2-4 dihydric alcohols include ethylene glycol, the propylene and butylene glycols and diethylene glycol. Suitable amine bases are listed. The products are dissolved in water; water-dilutability may be improved by adding 2-20 wt. per cent of, e.g., butanol or ethylene glycol butyl or ethyl ether. The paint may also contain a pigment and a phenol- or melamine-formaldehyde resin. In Examples 1-3 a linseed/ dehydrated castor oil mixture or soybean/ dehydrated castor oil or linseed oil fatty acid is heated with rosin and glycerol or pentaerythritol or a glycerol/epoxy resin mixture; the product is heated with maleic anhydride, then optionally with ethylene or propylene glycol, before being dissolved in water, optionally containing ethylene glycol butyl ether, and neutralized with triethylamine or isopropanolamine. The product is ground with rutile TiO 2 and used to coat steel plates, which are subsequently baked.