| 摘要 |
894,589. Photographic film supports with subbing layers. AGFA A.G. July 29, 1958 [July 29, 1957], No. 24413/58. Class 98(2). A support produced from a high molecular weight polyalkyleneterephthalate is provided with a subbing layer comprising a mixed acetal of a polyvinyl alcohol with an aldehyde containing at least one water-solubilising group and an aldehyde without a watersolubilising group, the acetal being soluble in organic solvent and being capable of swelling in water. Adhesion of a subsequently coated silver halide emulsion layer to the support is thereby attained. In Example 1 a foil formed from a condensation product of terephthalic acid and glycol is dipped in a solution of the acetal from polyvinyl alcohol and benzaldehyde-2,4-disulphonic acid together with benzaldehyde itself, and which contains free polyvinyl alcohol, using a solvent mixture of methanol, phenol and methylene chloride, dried and then cast with the emulsion which latter adheres satisfactorily both dry and when wet. In Example 2 benzaldehyde-2-monosulphonic acid replaces the disulphonic acid, a vinyl chloride, hydroxide and acetate copolymer is included in the solution, and the solvent is methanol, aniline and trichlorethylene; and in Example 3 the mixed acetal is formed from butyraldehyde sulphonate and tolyl aldehyde, a styrene and allyl alcohol copolymer is included therewith and methanol and acetone with trichloracetic acid is used as solvent. Other copolymers for use together with the mixed acetals and other liquids to form the solvents, which are designed to swell the foils superficially, are listed. Specifications 522,161, 688,528, 700,957, 718,422, 726,736, 727,705, 739,477 and 782,165 are referred to. |
