| 摘要 |
1,235,970. Radiation indicators. NITTO ELECTRIC INDUSTRIAL CO. Ltd. 9 July, 1969 [9 July, 1968], No. 4563/69. Heading C3P. [Also in Division H5] A radiation indicator comprises a chlorinecontaining polymer, an acid sensitive dye and 5-80 parts per 100 parts by weight of polymer of a plasticizer selected from phosphoric esters, chlorinated paraffin, a polyester or a trimellitic ester of an aliphatic alcohol. Preferably the indicator is formed by dissolving the components in a solvent, casting a film and evaporating the solvent to leave no more than 5% by wt. remaining in the film. The polymer is preferably PVC or vinyl chloride-acetate copolymer; the dye is a mixture of aniline blue with aniline yellow, methyl yellow, diethyl yellow or methyl red and optionally benzene azodiphenylamine. Suitable plasticizers are trichloroethyl phosphate, 40% chlorinated paraffin, adipic acid polyester of m.w. 1000-2000 or 2-ethylhexyl ester of trimellitic acid. Solvents used are tetrahydrofuran, cyclohexanone, diethyl formamide, and dioxane. The film made may be self-supporting or on an opaque backing of polyester film which may have a pressure-sensitive layer on the reverse. |
