| 摘要 |
1,015,925. Thermographic materials and transfer processes. EASTMAN KODAK CO. July 16, 1962 [July 14, 1961; June 27, 1962], No. 27283/62. Heading G2C. Copies are made by a thermographic transfer process using a material comprising a flexible support coated with either a crystalline polymer having a tackifying point between 50‹ and 200‹C. or a non-crystalline polymer admixed with a crystalline non-polymeric substance melting between 50‹ and 200‹C, the mixture having a tackifying point, which is imagewise exposed to infra-red radiation to produce a tacky image which remains tacky below the tackifying point, pressed against a receptor sheet to transfer at least part of the image and repeating the transfer on to further receptor sheets if desired. Specified crystalline polymers are polybutene, polypentene, poly(tetra- or penta-methylene) carbonate, polyethylene succinate, poly(2, 2 dimethyl trimethylene succinate, poly (1, 4 cyclohexanedimethylene adipate or succinate) polyethylene glycol, polypentamethylene terephthalate, polyethylene 1,4 cyclohexane dicarboxyolate and cyclohexanedimethylene adiphate/ azelate copolymers. Other polymers can be found among polyvinyls, polyacrylics, polyesters, polyamides, polyesteramides, poly-carbonates, polyethers, polyurethanes and polyureas. Non-crystalline polymers are atactic polystyrene, polyvinyl acetate, butadiene/styrene copolymer, polyalkyl acrylates and methacrylates, polyterpenes, poly vinyl butyral, cellulose butyrate or acetate butyrate, pllyethylene terephthalate, vinyl chloride/ vinyl acetate copolymer and phenol/formaldehyde resins. Crystalline non-polymeric substances specified are the benzoates of 4 biphenylyl, engenol, 4-cyclohexylphenyl and pentachlorophenyl; camphor;bensoin acetate; pentacrythritol tetra-isobutyrate; 2, 6 di-t-butyl-4-methyl phenol; triphenyl orthoformate; N, pentyl-1, 8-naphthali-mide; bis (o-methoxy-phenyl) carbonate; 2, 5, 5-triphenyl-1, 3-dioxolan-4-one; bis (benzyloxy di-phenylmethane and anthraquinone-2-carboxyethyl. The heat-sensitive layer may include dyes or substances to decrease the amount of polymer and modify the layer such as clay, glass beads, quartz, polymethylmethacrylate beads, titanium dioxide, zinc oxide, alkyl phthalates or fumarates,tricresyl phosphate, menthol, eugerol or isoeugenol. A polymeric overcoat such as polyvinyl alcohol or carboxymethylcellulose which is not porous to the tacky material may be applied to the heat-sensitive layer and removed before transfer. The heat-sensitive material may be "annealed" before exposure, i.e. heating the material to a temperature between the glass-transition temperature and the tackifying temperature to improve its crystallinity. Used materials may also be reclaimed by such annealing. The final copies may be used as hectographic or lithographic masters.
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