Patent GB-1354783-A (GB)
Title: Lacquers containing addition polymer isocyanate products
IPC: C08F283/00
Filed: 1971-06-23
Abstract: 1354783 Synthetic lacquers BAYER AG 23 June 1971 [25 June 1970] 29420/71 Headings C3P and C3R Lacquers contain as binder, or as binder component, a substantially non-cross-linked graft copolymer of: (a) 10-89À7% (by weight) of an aliphatic, cycloaliphatic and/or araliphatic polyisocyanate, (b) 10-70% of methyl methacrylate, (c) 0À3-10% of an olefinically unsaturated compound which contains at least one isocyanate group or a group which is reactive with isocyanate groups, and (d) 0-25% of one or more other olefinically unsaturated compounds. (The term "graft polymer" is used for polymers obtained by a reaction in which an olefinically unsaturated monomer has been grafted onto a compound which does not contain olefinic double bonds but which contains methylene groups activated by isocyanate groups.) The polyisocyanate (a) preferably is one that contains at least one H atom attached to the carbon atoms adjacent to the isocyanate groups; many examples of such polyisocyanates are listed. Examples of compound (c) are allyl alcohol, hydroxyethyl and hydroxypropyl acrylates and methacrylates, mono-esters of maleic and itaconic acids, dihydroxy diesters of maleic and itaconic acids, allylamine, acrylamide, methacrylamide, acrylic acid, methacrylic acid N-methylolacrylamide, N - methylolmethacrylamide, # - isocyanatoethyl methacrylate, vinyl isocyanate and allyl isocyanate. The optional component (d) may be, for example, an olefin, conjugated diene, alkyl acrylate or methacrylate, vinyl ester of a carboxylic acid, vinyl or vinylidene chloride, methyl vinyl sulphone, N - vinylpyrrolidone, styrene or an alkyl styrene, methyl vinyl ketone, acrylonitrile, methacrylonitrile, diester of maleic or itaconic acid, N-methylol alkyl ether of acrylamide or methacrylamide, a reaction product of methoxymethyl isocyanate with a hydroxyalkyl (meth)acrylate, allyl glycidyl ether, butadiene monoxide, glycidyl acrylate or glycidyl methacrylate. The binder can be prepared by polymerizing the monomer components in bulk or in solution in organic solvents using free radical generators and/or heat and/or high energy radiation, optionally in combination with photosensitizers. The binder contains free isocyanate groups and can be modified by reaction with small amounts of compounds that are reactive with isocyanates, provided that no cross-linking takes place; such reactive compounds are a polyester of adipic acid and ethylene glycol having a molecular weight of approximately 2000 and a branched polyester of phthalic acid, trimethylolpropane, butane-1, 3-diol and 2,2-bis-(4-hydroxycyclohexyl)-propane. The binder can also be used in blocked or partly blocked isocyanate form for the production of storing lacquers. The binder can be used in a 1-component lacquer and hardens by reacting with atmospheric moisture. Also, the binder (blocked or unblocked) can be used in a 2-component lacquer system wherein the second component comprises a compound containing more than one hydroxyl, SH, NH or COOH group. The lacquer preferably includes a conventional urethanation catalyst in order to promote hardening and may optionally contain a pigment, e.g. titanium dioxide.