| 摘要 |
<p>1,119,848. Printing Processes &c. MINNESOTA MINING & MFG. CO. 8 Sept., 1965 [22 Sept., 1964], No. 38422/65. Heading B6C. A printers' blanket comprises (1) a support layer of rubber containing up to 40% of uniformly distributed voids, (2) a foundation sheet, and (3) a rubber transfer layer. (1) The support layer is formed with grooves 19 producing islands 20, and comprises rubber having a wire mesh screen forced into it, or foamed rubber. A suitable rubber composition is 100 parts of a 67:33 butadiene :acrylonitrile copolymer rubber, 5 parts zinc oxide, 94 parts carbon black, 20 parts di-butoxy-ethyl sebacate, 2 parts N-nitroso diphenyl amine, 1À5 parts stearic acid, 1À65 parts sulphur, 1À35 parts benzothiazyl disulphide, and 0À22 parts tetramethyl thiuram monosulphide. (2) The foundation sheet is two-ply, and comprises (a) adjoining the support layer, a foil of polyethylene terephthalate, polypropylene, polycarbonate or glass cloth, and (b) adjoining the transfer layer, a layer of cellulose acetate rayon cloth or glass cloth. Layers (a) and (b) are formed by adhesive. (3) The transfer layer comprises a butadiene: acrylonitrile copolymer rubber with clay and calcium carbonate as fillers. Layers (1) and (2), (2) and (3) are joined by adhesive. Compositions of the adhesives are described. After laminating the assembly is ground and polished.</p> |
