ZrO.sub.2 - containing glass-ceramic

• US 5,698,482 A
• Filed: 06/30/1995
• Issued: 12/16/1997
• Est. Priority Date: 07/01/1994
• Status: Expired due to Term

• Current Assignee: Ivoclar AG
• Original Assignee: Ivoclar AG
• Inventors: Rheinberger, Volker, Frank, Martin, Hoeland, Wolfram
• Primary Examiner(s): Bell, Mark L.
• Assistant Examiner(s): TROILO, LOUIS
• Application Number:
  US08/496,936
• Time in Patent Office: 900 Days
• Field of Search: 501/5, 501/6, 501/10, 501/32, 501/63, 501/103, 501/104, 106/35
• US Class Current: 501/10
• CPC Class Codes: A61K 6/816 comprising titanium oxide
• CPC Class Codes: A61K 6/818 comprising zirconium oxide
• CPC Class Codes: A61K 6/822 comprising rare earth metal oxides
• CPC Class Codes: A61K 6/824 comprising transition metal oxides
• CPC Class Codes: A61K 6/833 Glass-ceramic composites
• CPC Class Codes: C03C 10/0009 containing silica as main constituent
• CPC Class Codes: C03C 4/0021 for dental use

Abstract

A ZrO₂ -containing glass ceramic is described, the main crystalline phase of which is formed by ZrO₂ and which has at least one further crystalline phase, and which can be used in particular in dentistry.

Claims

1. A ZrO₂ -containing glass-ceramic composition, comprising a ZrO₂ crystalline phase, a lithium phosphate crystalline phase, and at least one additional crystalline phase, and comprising the following components:

space="preserve" listing-type="tabular">______________________________________ Component % by wt. ______________________________________ SiO.sub.2 42.5 to 58.5 Al.sub.2 O.sub.3 0 to 7.0 La.sub.2 O.sub.3 0 to 9.5 Li.sub.2 O 7.0 to 14.5 Na.sub.2 O 0 to 7.5 K.sub.2 O 0 to 13.5 P.sub.2 O.sub.5 4.0 to 13.5 ZrO.sub.2 15.0 to 28.0 TiO.sub.2 0 to 6.0 F 0 to 2.0 BaO 0 to 6.5 CaO 0 to 6.0 B.sub.2 O.sub.3 0 to 3.3 CeO.sub.2 0 to 3.0. ______________________________________

2. The glass-ceramic composition according to claim 1, comprising the following components:

space="preserve" listing-type="tabular">______________________________________ SiO.sub.2 47 to 55% by wt. Al.sub.2 O.sub.3 0 to 5% by wt. Li.sub.2 O 7 to 14% by wt. Na.sub.2 O 0 to 6% by wt. K.sub.2 O 0 to 8% by wt. P.sub.2 O.sub.5 5 to 11% by wt. ZrO.sub.2 16 to 25% by wt. F 0 to 1.5% by wt. ______________________________________

3. The glass-ceramic composition according to claim 1, wherein the ZrO₂ crystalline phase contains ZrO₂ in tetragonal modification.

4. The glass-ceramic composition according to claim 1, wherein a further crystalline phase is formed by an SiO₂ crystalline modification and/or an AlPO₄ modification isotypic to SiO₂.

5. The glass-ceramic composition according to claim 1, wherein the glass-ceramic composition is translucent.

6. The glass-ceramic composition according to claim 1, wherein the glass-ceramic composition has a flexural strength of up to 400 MPa.