http://rdf.ncbi.nlm.nih.gov/pubchem/patent/CA-1142645-A
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_98604a09a20411fcde1de9b4effe7ff4 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/G11B7-245 |
| filingDate | 1979-12-07-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| grantDate | 1983-03-08-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| inventor | http://rdf.ncbi.nlm.nih.gov/pubchem/patentinventor/MD5_e34e2cbb609e3757d2c47d31b7ed09e6 |
| publicationDate | 1983-03-08-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | CA-1142645-A |
| titleOfInvention | Video disc composition and method for molding |
| abstract | ABSTRACT A videodisc member is described having a uniform value of birefringence over the entire information storage surface of the disc. This value of birefringence is the same at the inner information storage radius as at the outer information storage radius. The preferable composition of the videodisc is either a specially prepared polymethylmethacrylate, referred to as PMMA, or a combination of PMMA and acrylic rubber. The method of molding the improved videodisc member includes an extended drying time for said composition and increasing the melting temperature. The increase in melt temperature provides a low and uniform value of birefringence. The improved drying cycle eliminates splay marks, blisters and other surface imperfections as compared to manufacturer recommended drying times. |
| priorityDate | 1979-12-07-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
Total number of triples: 19.