Barium-free dental glass having good x-ray absorption

US5641347A · kind A · utility

Assignee

• Schott Glaswerke · DE

Inventors

• Danuta Grabowski · Wiesbaden, DE
• Marc Clement · Mainz, DE
• Johann Daimer · Bad Aibling, DE
• Hartmut Paschke · Ergolding, DE

Key dates

• Filing date: Nov 2, 1995
• Grant date: Jun 24, 1997
• Expiry date: Nov 2, 2015

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C03C4/087
• WIPO field: Pharmaceuticals
• WIPO sector: Chemistry

Abstract

Disclosed is a barium-free glass of good x-ray absorption, which has a composition (in wt.-% on the oxide basis) of SiO.sub.2 50-75; ZrO.sub.2 5-30; Li.sub.2 O 0-5; Na.sub.2 O 0-25; K.sub.2 O 0-25; .SIGMA. alkali oxides 0-25. Preferred is a dental glass of the composition of SiO.sub.2 55-70; ZrO.sub.2 10-25; Li.sub.2 O 0-15; Na.sub.2 O 10-25; K.sub.2 O 0-15; .SIGMA. alkaloids 15-25. The glass can furthermore contain also up to 3 wt.-% of fluorine, up to 5 wt.-% of MgO, up to 5 wt.-% of TiO.sub.2, and in each case up to 10 wt.-% of the oxides Al.sub.2 O.sub.3, GeO.sub.2, P.sub.2 O.sub.5, La.sub.2 O.sub.3, Y.sub.2 O.sub.3, Ta.sub.2 O.sub.3, Gd.sub.2 O.sub.3, ZnO and Nb.sub.2 O.sub.5. The glass finds its use in powder form with an average particle size of .ltoreq.10 .mu.m as filler for dental composites for filling teeth.