http://rdf.ncbi.nlm.nih.gov/pubchem/patent/GB-650399-A
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_1e70c0aeade92d7571d955d3b90ea06e |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C09D127-18 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C09D127-18 |
| filingDate | 1948-05-21-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationDate | 1951-02-21-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | GB-650399-A |
| titleOfInvention | Improvements in or relating to dispersions of fluorine-containing polymers |
| abstract | An aqueous colloidal dispersion of polytetrafluorethylene containing a water-soluble surface-active agent is admixed with a hydrous oxide sol containing 5 per cent to 50 per cent of oxide based on the polytetrafluoroethylene. The colloidal particles present have a size in the range 0.2 to 1 micron. The hydrous oxides are selected from the Group III and IV elements which form colloidal hydrates, dehydrate at less than 300 DEG C. to refractory solid oxides, and are insoluble in water, e.g. hydrated silicon or titanium dioxides, aluminium and zirconium oxides. The silica sols may be stabilized with 0.1 per cent to 1 per cent of an alkali metal hydroxide. The surface-active agents are preferably anion-active for silica and cation-active for alumina and may be (a) alkali metal or ammonium salts of long-chain carboxylic or sulphonic acids or sulphate esters, e.g. an alkyl sodium sulphate derived from coconut oil alcohols; (b) salts of long-chain amines or quaternary ammonium bases with a long-chain alkyl group, e.g. dodecylamine acetate; or (c) non-ionic types such as polyalcohols, polyglycol ethers or vegetable gums. In an example (4) a colloidal dispersion of polytetrafluoroethylene containing dodecylamine acetate and alumina sol is coagulated with ammonium bicarbonate, the precipitated floc filtered and peptized by addition of acetic acid to a pH of 5.6, after which the dispersion is concentrated by evaporation. The dispersions may be coated on to copper wire or glass and baked. Specifications 572,265, 583,418, 584,851, 599,580 and 631,504 are referred to. |
| priorityDate | 1947-05-23-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
Total number of triples: 36.