| 摘要 |
1,229,077. Photographic bleach-fix solutions. EASTMAN KODAK CO. Dec. 12, 1969 [Dec. 13, 1968], No. 60786/69. Heading G2C. Photographic bleach/fix solutions are regenerated by the addition of iodine which oxidises the reduced oxident in a spent solution and precipitates the dissolved silver, which is removed. The iodine maybe added in solid, liquid or gaseous form in an amount up to 1À2g per g. of silver in solution. Suitable bleaches include those providing cupric, cobaltic or ferric ions, water-soluble quinones and complex salts of an alkali metal and a polyvalent cation with an organic acid having one of the formula: - wherein X represents a hydrocarbon residue, oxygen, sulphur or an MR<SP>12</SP> group. Suitable fixing agents are water-soluble sulphur-containing organic diols or dibasic acids, their water-soluble salts or an imidazolidinthione. |
