Powder coatings containing copolymer containing isobornyl methacrylate as melt flow modifier
AssigneeRohm and Haas Company
InventorWilliam H. Brendley, Jr.
Life of this patent
Estimating the term…
Abstract
Low molecular weight copolymers of (1) acrylic acid esters or methacrylic acid esters of alcohols such as methanol with (2) esters of bicyclic alcohols such as isobornyl alcohol and unsaturated acids such as methacrylic acid, as contrasted with high molecular weight copolymers of such monomers (1) and (2) (see U.S. Pat. No. 3,485,775) and as contrasted to other acrylic polymers, are found to be exceptional in compatibility with practically all types of hard coating resins, and to lower the flow temperature of the mixture when using powder coating methods such as an electrostatic spray or a fluidized bed, electrostatic or not, as compared with the use of the hard coating resin alone.
Claims11
A method of coating an article comprising the steps of applying a layer of a fusible polymeric powder to the article, the powder being a mixture of (A) about 3 to 10 parts by weight of a melt flow-modifying copolymer of about 40 percent to 60 percent by weight of a compound of the formula ##STR9## where R is selected from the group consisting of --CH.sub.2 --, --CH(CH.sub.3)--, and --C(CH.sub.3).sub.2 --, and M is selected from the group consisting of a hydrogen atom and at least one methyl group, and 40 percent to 60 percent by weight of a comonomer in the form of styrene, vinyl toluene, or at least one ester of acrylic acid or methacrylic acid and an aromatic, monocyclic aliphatic, or open chain aliphatic alcohol or alkoxy alcohol having from 1 to about 18 carbon atoms, or combinations thereof, said copolymer having an average molecular weight of from 1,000 to 8,500, and (B) 90 to 97 parts by weight of a coating resin selected from the group consisting of cellulose esters, nylons, epoxies, silicones, polysulfides, polycarbonates, polysulfones, polyphenylene oxide, polyimides, polyxylylenes, polyolefins, polyvinylhalides, acrylic ester polymers, chlorinated polyethers, and polyhaloolefins, fusing the layer while on the article, and cooling the article.
Dependencies are inferred from the claim text.