http://rdf.ncbi.nlm.nih.gov/pubchem/patent/GB-478945-A
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_59bed722b146ab4ef9e0d5f63882295d http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_9799ffcda2dbb45041a5ab0fd08dd5fe |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C09B23-102 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/G03C1-16 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C09B23-04 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C09B23-04 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/G03C1-16 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C09B23-10 |
| filingDate | 1936-04-24-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationDate | 1938-01-24-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | GB-478945-A |
| titleOfInvention | Manufacture of cyanine dyes, and their use in modifying the properties of photographic emulsions |
| abstract | Photographic gelatino-silver halide emulsions are sensitized by means of dyestuffs containing a benzthiazine nucleus and having the formula <FORM:0478945/IV/1> or <FORM:0478945/IV/2> where A = H or alkyl, D = vinylene or phenylene, R and R1 = organic residues, X = an acid radicle, Y =--CH2--S-- or --S--CH2-- and Z = the non-metallic atoms necessary to complete a heterocyclic nucleus. Thus R and R1 may be methyl, ethyl, n-butyl, decyl, allyl, or benzyl, X may be halide, alkylsulphate, perchlorate, or p-toluene sulphonate and Z may represent the atoms necessary to complete a 5-membered heterocyclic nucleus, e.g. an oxazole, thiazole, selenazole, indolenine, thiazoline, selenazoline or a 6-membered heterocyclic nucleus, e.g. pyridine or quinoline. The dyes are obtained by condensing a quaternary salt of a 3-alkylthiol derivative of a 2 : 4-or 1 : 4-benzthiazine with a cyclammonium quaternary salt containing a reactive alkyl group in the a - or g -position. Instead of the salts and the respective bases and alkyl salts may be used. A basic condensation agent may be added. In the examples: (1) - (6) 3-methylthiol-2 : 4-benzthiazine is fused with ethyl-p-toluenesulphonate and 1-methylbenzthiazole, quinaldine, 1-methylbenzselenazole, 1 - methyl - 5 : 6 - benzbenzthiazole, 1-methyl3 : 4-benzbenzoxazole or 2-methylthiazoline; the reaction mass is dissolved in alcohol, in some cases refluxed with triethylamine to complete the condensation, and the dye precipitated with potassium iodide, (7) 3-methylthiol - 1 : 4 - benzthiazine, 1-methylbenzthiazole and methyl-p-toluenesulphonate are heated together and the dye precipitated as above. A sample has been furnished under Sect. 2 (5) of the dyestuff made by condensing 3 - ethylthiol - 2 : 4 - benzthiazine methiodide and 1-ethylbenzthiazole ethiodide in alcohol in presence of triethylamine. The dyes are added to the emulsions so that the concentration of dye is 10--20 mg./litre of emulsion. 3 - Methylthiol - 2 : 4 - benzthiazine is made by electrolytic reduction of anthranilic acid to o-aminobenzyl alcohol, treating the latter with alcoholic potassium hydroxide and carbon disulphide to form 3-thiol-2 : 4-benzthiazine and methylation. The quaternary salts are made e.g. by heating with methyl iodide or sulphate. 3 - Methylthiol - 1 : 4 - benzthiazine is made by reduction of o-nitrophenylthioglycollic acid to 3-ketodihydro-1 : 4-benzthiazine, treating the latter with phosphorus pentasulphide in boiling xylene and methylating. |
| priorityDate | 1936-04-24-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
Total number of triples: 79.