http://rdf.ncbi.nlm.nih.gov/pubchem/patent/GB-765250-A
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_f118956b1b7105c9778e2a2a3b839707 http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_6f837d69deabc525495a0cb3f3ce73c0 |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/G03C5-383 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/G03C5-38 |
| filingDate | 1955-02-08-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationDate | 1957-01-09-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | GB-765250-A |
| titleOfInvention | Combined developer and fixer |
| abstract | 765,250. Photographic developing and fixing compositions. GOLDHAMMER, J. S., and MAURER, J. A. Feb. 8, 1955 [Feb. 15, 1954; Feb. 15, 1954], No. 3725/55. Class 98(2) A combined photographic developing and fixing composition comprises a dihydroxybenzene, a developing agent of the amidol type (i.e. one having a total of more than two amino, substituted amino or hydroxyl groups attached to the same benzene ring) an alkali, a fixing agent and an inorganic reducing agent such as sodium sulphite. In aqueous solution the pH is not in excess of 9.5. It may also contain a density building organic developer and an antifogging agent. The preferred dihydroxybenzene is hydroquinone, but catechol or resorcinol may be used. The alkali may be sodium carbonate or an alkali metal hydroxide and the fixer may be sodium, ammonium, potassium or calcium thiosulphate or sodium or potassium thiocyanate or cyanide. A preferred combination is the use of ammonium thiosulphate and sodium hydroxide. The density building developer may be catechol, p-hydroxypheriyl . glycin or chloro, dichloro, bromo, or dibromohydroquinone. The antifoggant may be benztriazole, 6-nitrobenzimidazole nitrate or an alkali metal bromide. Specified developers of the " amidol type " are amidol, 2:4-diaminoresorcinol, 6-methyl-2:4-diamino phenol, 5- methyl - 2:4 - diaminophenol, 4 - amino - 6 - methyl-2-methylaminophenol, 6-amino-4- methyl-2-methylaminophenol, 5-dimethylamino-2-methylaminophenol, 1: 2: 4 - triaminobenzene, 5-methyl-1:2:4-triaminobenzene, 4-hydroxy-2':4'-diamino-diphenylamine, 4:2<SP>1</SP>:4<SP>1</SP>-triamino-diphenylamino and 1:3-diamino-4:6-dihydroxybenzene. Specification 11872/93, [Class 98], is referred to. |
| priorityDate | 1954-02-15-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
Total number of triples: 63.