Patent GB-1102683-A (GB)
Title: Water-dilutable stoving lacquers
IPC: C09D5/44
Filed: 1965-05-28
Abstract: A water-dilutable stoving lacquer consists of (a) a plasticized synthetic resin which is a copolymer of a polymerizable vinyl or vinylidene compound containing at least one acid equivalent of a ,b -ethylenically unsaturated carboxylic acid for each 1800 grams of the total monomer mixture and wherein polymerization has been effected in the presence of an alkyd resin containing ethylenic double bonds, free carboxyl groups (acid number at least 35) and hydrophilic groups; and (b) ammonia or a strong organic nitrogen-containing base forming a soap with the plasticized synthetic resin.  The diluting water may contain a completely or substantially water-miscible organic solvent; and the lacquer may contain wetting agents and/or emulsifiers.  The alkyd resin may be formed from e.g. succinic, maleic or terephthalic acid or an adduct between e.g. fumaric acid and e.g. dehydrated castor oil or abietic acid and a polyhydric alcohol.  The alkyd resin may be reacted with the vinyl or vinylidene monomer in presence of a solvent.  Monomers specified include methyl acrylate, n-butyl crotonate, 6-hydroxy-n-hexyl acrylate and the corresponding methacrylates, ethacrylates, and phenylacrylates, di - (2 - hydroxy - n - propyl)-maleinate, 2 - hydroxy - 3 - chloro - n - propylacrylate, styrene, nuclear- and chain-substituted styrenes, acrylamide, and methacrylonitrile. The a ,b -unsaturated carboxylic acids specified include acrylic, b -benzoylacrylic, cinnamic, aconitic, and chloromaleic acids. Monomers containing carboxylic groups may be reacted individually or in mixture, individually in mixture with non-carboxylic monomers, or in mixture with mixtures of the other monomers. The organic bases specified include ethylamine, trimethylamine, piperidine, diethanolamine, diglycol amine, and triethylenetetramine.  The copolymerization temperature should not exceed 160 DEG  C., and the catalyst may be di-t-butyl or benzoyl peroxide, cumene hydroperoxide or a Redox system.  In Example 1, an alkyd resin is formed from ricinene and soya-bean oils, colophony, and pentaerythritol, and is successively reacted with maleic anhydride, butanol, and trimethylol propane.  A solution of the product in the mono-n-butyl ether of ethylene glycol is mixed with butyl methacrylate, methyl methacrylate, acrylic acid, di-t-butyl peroxide and lauryl mercaptan, the mixture is kept at 130 DEG  C., and the resulting resin is neutralized with aqueous ammonia and diluted with distilled water.  In Example 2, a mixture of ricinene, tall, and linseed oils and colophony is reacted with maleic anhydride and the product is esterified with ethylene glycol and pentaerythritol.  A solution of the resin in the mono-n-butyl ether of ethylene glycol is mixed with methyl and butyl methacrylates, acrylic acid and di-t-butyl peroxide and the mixture is kept at 130 DEG  C. for two hours.  The resin is neutralized with triethylamine, diluted with distilled water, ground with ferric oxide red, and further diluted.ALSO:Electro-phoretic coating is effected using a water-dilutable stoving lacquer consisting of (a) a plasticized synthetic resin which is a copolymer of a polymerizable vinyl or vinylidene compound and an a , b -ethenylically unsaturated carboxylic acid which contains at least one acid equivalent of copolymerizable a , b -ethylenically unsaturated carboxylic acid for each 1800 grams of the total monomer mixture and wherein polymerization has been effected in the presence of an alkyd resin containing ethylenic double bonds, free carboxyl groups (acid number at least 35) and hydrophilic groups, and (b) ammonia or a strong organic nitrogen-containing base forming a soap with the plasticized synthetic resin.  The lacquer may be diluted with water to a solids content of 10% and poured into the electro-phoresis tank, the metallic object to be coated dipped therein to serve as the anode, and a D.C. voltage of about 100 applied.  The deposited lacquer is stoved at 150-170 DEG C.