Lead aluminoborofluorosilicate moldable glasses

• Main Authors: LEROY, DOMINIQUE LEONCE JULES, MAZEAU, JEAN-PIERRE LE PRES DE VULAINES
• Format: Patent
• Language: English; French; German
• Published: 18.04.1984
• Subjects: CHEMICAL COMPOSITION OF GLASSES, GLAZES, OR VITREOUSENAMELS; CHEMISTRY; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GLASS; JOINING GLASS TO GLASS OR OTHER MATERIALS; METALLURGY; MINERAL OR SLAG WOOL; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS,MINERALS OR SLAGS; SURFACE TREATMENT OF GLASS; TECHNICAL SUBJECTS COVERED BY FORMER USPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ARTCOLLECTIONS [XRACs] AND DIGESTS

Optical glass compositions capable of being shaped under the combined action of temperature and pressure in a mold so as to obtain articles having surfaces exhibiting highly precise reproduction of the mold walls have the following constitution:-… SiO2 8-20… B2O3 5-20… PbO 50-70… Al2O3 1-11… F 2-7… expressed in terms of weight percent on the oxide basis. The glasses demonstrate softening points not exceeding 500 DEG C, refractive indices between 1.65-1.82 and Abbe numbers between 27-39.