UEberzugsgemische und Verfahren zu deren Herstellung

A polyester is the reaction product of (I) a monoepoxy alcohol which is a 4-oxatetracyclo [6.2.1.02'7.O3'5] undecane substituted in the 9, or 9, 10 or 10, 11 positions by hydroxy, hydroxyalkoxy, polyhydroxyalkoxy, or hydroxy-(polyalkyleneoxy) groups, or a 10-oxapentacyclo [6.3.1.13'6.O2'7.O9'11] tridecane substituted in the 4 or 4,5 positions by the above groups or by hydroxylkyl, hydroxyalkoxymethyl, polyhydroxyalkoxymethyl or hydroxy-(polyalkyleneoxy) alkyl groups; (II) a saturated or unsaturated fatty acid or oil sufficient to provide 0.1 to 1.0 carboxy groups per hydroxy group of (I); and (III) a polycarboxylic acid or anhydride sufficient to provide 0.2 to 3.0 carboxy groups per epoxy group of (I). Coating compositions contain the polyester preferably dissolved in an inert solvent, e.g. an aromatic cycloaliphatic or paraffin hydrocarbon or a ketone or ether, which may have been used as a medium for the polyesterification. Preferred monocarboxylic acids (II) include hexanoic, caprylic, lauric, capric, myristic, palmitic, stearic, arachidic, palmitoleic, oleic, linoleic, linolenic, eleostearic, licanic, ricinoleic, hexenoic hexadienoic, and octenoic acids, and mixtures derived from castor, dehydrated castor, coconut, cottonseed, linseed, oiticica, perilla, olive, safflower, sardine, soybean, tung or tall oils. Suitable polycarboxylic acids (III) include oxalic, malonic, succinic, adipic, pimelic, suberic, sebacic, alkyl- and alkenylsuccinic, maleic, fumaric, glutaconic, isopropylidene-malonic, muconic, diglycollic, dilactic, 2-carboxy - 2 - methyl - cyclohexaneacetic, phthalic, 1:2 - naphthalene dicarboxylic, 5 - octene-3:3:6 - tricarboxylic, 1:2:4 - benzene - tricarboxylic, 1:2:3:4 - benzene - tetracarboxylic acids and polymerized fatty acids and polycarboxy polyesters. A large number of suitable anhydrides are also listed. These include glutaric, succinic and alkylsuccinic, maleic and chloromaleic, itaconic, citraconic, phthalic and various hydro- and halophthalic, chlorendic and other Diels Alder anhydrides, and polymeric iso- and terephthalic anhydrides. A preferred component (III) comprises a major amount of tetrahydrophthalic anhydride and a minor amount of maleic anhydride. Suitable catalysts include HClO45H2SO4, H3PO4, alkyl an aryl sulphonic acids, tetraalkyl titanates, NaOH, KOH, Li acetate, and tertiary amines. The product solutions may be used as paints and may have added thereto driers e.g. Co naphthenate or Co or Pb octoate, fillers and pi