| 摘要 |
<p>A bead polymer of methyl methacrylate and lauryl methacrylate is prepared by polymerization in an aqueous phosphate buffer solution in the presence of benzoyl peroxide. A composition of this polymer with titanium dioxide, modified bentonite, plasticizers, solvents, nitro-cellulose and cellulose acetate is used as a top coat over a primer containing cellulose acetatebutyrate. Example (7) describes a blend of the above copolymer and a butoxylated copolymer of acrylamide, styrene, ethyl acrylate and methacrylic acid. Specification 989,684 is referred to.ALSO:A coated article comprises a layer of primer and a superimposed layer of a polymer of an alkyl methacrylate, the primer containing cellulose acetate-butyrate; the subject-matter of Specification 989,684 is excluded. The primer may contain a drying oil modified alkyd resins, a rosin modified alkyd resin, mixed or co-reacted alkyd and amino-formaldehyde resins, mixed or co-reacted alkyd resins, amino-formaldehyde resins and epoxy resins, mixed or co-reacted higher fatty acid esters of epoxy resins with alkyd resins and/or amino-formaldehyde resins, or the thermosetting co-reaction products of acid-containing acrylic resins with amino-formaldehyde resins, in addition to the cellulose ester; it may be in the form of a solution or an emulsion. The top coat may be a homopolymer of an alkyl methacrylate or a copolymer of methyl methacrylate with an ester of acrylic acid, methacrylic acid or itaconic acid, and may contain pigments such as titanium dioxide, suspending agents such as organic-modified bentonite, plasticizers, cellulose acetate and nitrocellulose.</p> |
