Patent · US Expired

Opal glasses having an apatite opacifying phase

US4536480A · kind A · utility

9Cited by
3References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 23, 1984
Grant dateAug 20, 1985
Priority date
Expiry dateMar 23, 2004

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC03C4/005
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

This invention is drawn to spontaneous opal glasses containing an apatite-type crystal opacifying phase and exhibiting a temperature interval between the emulsion and high temperature crystallization liquidi of at least 50.degree. C. which consist essentially, in weight percent on the oxide basis, of ______________________________________ Na.sub.2 O 7.5-11 B.sub.2 O.sub.3 2-4.5 K.sub.2 O 0-5 SiO.sub.2 57-65 Na.sub.2 O + K.sub.2 O .ltoreq.13 P.sub.2 O.sub.5 2-5.5 BaO 0-9.5 F 1.5-4 CaO 0-3 SrO 0-5 ZnO 0.4-5 MgO 0-2.5 Al.sub.2 O.sub.3 8-13 SrO + MgO 0-5 ______________________________________ CaO and/or SrO and/or BaO at least 2.5 mole %.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.