| 摘要 |
Cellulose acetate film, suitable as a non-inflammable motion picture film base, is obtained by casting a solution of the triacetate (acetyl content 42.5-44.0 per cent) in a solvent mixture comprising methylene chloride, an unsubstituted aliphatic monohydric alcohol, e.g. methyl or ethyl alcohol, and 4-11 per cent, based on the total solvent mixture, of cyclohexane, on a surface preferably maintained at 55-85 DEG F. Plasticizers, e.g. triphenyl or tricresyl phosphate, diethyl or dibutyl phthalate and tripropionin, may be incorporated. The solution is preferably made by dissolving the triacetate in methylene chloride-methyl alcohol and then incorporating the cyclohexane with more methylene chloride. The film may be stripped from the surface in less than 4 minutes. Specifications 640,730 and 640,731 are referred to.
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