| 摘要 |
871,684. Photographic developers. AGFA A. G. May 8, 1959 [May 10, 1958], No. 15938/59. Class 98(2) A photographic silver halide developer solution comprises a 4-amino-5-pyrazolone, hydroquinone and either 1-phenyl-3-pyrazolidone or 1-(p-aminophenyl)-3-amino-pyrazoline. The 4-amino-5-pyrazolone may be one of those disclosed in Specification 765,286, especially 1-phenyl- 4-amino- 5-pyrazolone- 3- carboxylic acid and its amides and esters. In the examples, the developer solutions contain also sodium sulphite, sodium carbonate and sodium hexametaphosphate. |
