| 摘要 |
1497843 Coating surface activated polyolefine films SOC ITALIANA RESINE SIR SpA 25 May 1976 [11 June 1975] 21718/76 Heading B2E A surface activated polyolefine film, e.g. monoaxially or biaxially stretched polyethylene or polypropylene which has been activated chemically, by oxidising solutions, flame treatment or electric discharges, is coated with an organic solvent solution of a vinylidene copolymer material containing 35 to 60% vinylidene chloride, 30 to 50% of one or more alkyl esters of acrylic and/or methacrylic acid, e.g. C 1 -C 12 esters such as methyl, ethyl, butyl, isobutyl and 2-ethyl hexyl, 1 to 10% acrylic and/or methacrylic acid and 1 to 10% one or more hydroxyalkyl esters of acrylic and/or methacrylic acid, e.g. 2-hydroxyethyl acrylate and methacrylate and 2- hydroxypropyl acrylate and methacrylate, the ratio between the number of carboxyl groups and the number of hydroxyl groups being 0.5:1 to 5:1. The material consists of one or more copolymers each comprising moities of vinylidene chloride and alkyl esters, any copolymer which does not contain hydroxy alkyl esters containing acrylic acid and/or methacrylic acid and the solution containing a cross linking catalyst which liberates acid at not less than 70‹C. The coated film is heat treated at 70 to 130‹C. Suitable catalysts include the salt of an organic or inorganic acid, e.g. maleic, fumaric, p-toluene sulphonic or phosphoric, with a tertiary amine, e.g. trimethylamine, triethylamine, propyldimethylamine and triisopropylamine. Other catalysts include acid esters of polybasic inorganic acids or polycarboxylic organic acids with aliphatic alcohols, e.g. monobutyl phosphate, dibutyl phosphate, monobutyl maleate and monobutyl phthalate. A layer of an adhesion promoter, e.g. polyimines such as polyethyleneimine or prepolymerised polyesters or isocyanates, may be applied. The vinylidene copolymer material may be applied by gravure roll, reverse roll or kiss roll. |
