http://rdf.ncbi.nlm.nih.gov/pubchem/patent/GB-1493196-A
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_e9e11ac16e9c5716e1f3e12ecaeb06ff |
| classificationCPCAdditional | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C03B2215-48 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C03C2218-355 |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C03B17-02 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C03B18-12 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C03B23-26 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C03B23-207 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C03B23-22 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C03B23-0302 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C03B23-047 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C03B23-037 http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C03B11-08 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C03B23-26 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C03B17-02 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C03B23-037 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C03B11-08 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C03B23-047 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C03B18-12 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C03B23-03 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C03B23-22 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C03B23-207 |
| filingDate | 1975-04-11^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationDate | 1977-11-23^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | GB-1493196-A |
| titleOfInvention | Methods of producing glass articles with ophthalmically finished surfaces |
| abstract | 1493196 Ophthalmic quality glass articles AMERICAN OPTICAL CORP 11 April 1975 15075/75 Heading ClM A glass article having at least one surface of ophthalmic quality is made by: (a) covering at least one surface of a first layer of glass with a layer of a removable glass, the glasses being fused together along their interface to form a preform; (b) flattening the preform so that a smooth surface is produced at the interface; (c) heat-softening and shaping the preform to at least approximately the desired shape; and (d) removing the covering layer of glass to expose the smoothed surface of said first glass. The first glass layer 22 (fig. 3) may be formed on the surface of molten tin 28, the covering glass 30 being applied to the upper surface 36 (from supply 32 of molten glass) to form preform 18. Covering glass 30 may alternatively be applied in frit form (Fig. 7, not shown). Preform 18 may be flattened on the molten tin surface, or between rollers (34). Preform 18 may alternatively be formed by vapour deposition of the coating glass on a rigid piece of the first glass (Fig. 8, not shown), or by forming a rod/tube assembly which is heated and drawn down to a flat preform configuration (Fig. 9, not shown). Preform 18 (Fig. 4) may be cut into lens blanks 40 at station 38, the blanks 40 then passing along conveyer 44 before loading into moulds 46. In moulds 46 the blanks may be pressed by plunger 52 to form a lens of meniscus configuration (Fig. 5, not shown). The glass covering layer, which preferably has an expansion coefficient compatible with that of the first glass layer, is then removed, e.g. by etching in 5-10% by volume HCl solution at about 65 C. (Fig. 6, not shown). A suitable glass for the substrate is ophthalmic crown glass, and the covering glass may consist of, by weight: SO 2 12À7%, B 2 O 3 17À2%, BaO 46%, Al 2 O 3 2%, La 2 O 3 12%, ThO 2 9À6% and As 2 O 3 0À5%. |
| priorityDate | 1974-03-18^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
| Predicate | Subject |
|---|---|
| isDiscussedBy | http://rdf.ncbi.nlm.nih.gov/pubchem/substance/SID419524915 http://rdf.ncbi.nlm.nih.gov/pubchem/compound/CID5352426 |
Showing number of triples: 1 to 30 of 30.