Low melting point glass composition excellent in water resistance

Patent metadata

Field	Value
Publication number	US-10988403-B2
Application number	US-201916256072-A
Country	US
Kind code	B2
Filing date	Jan 24, 2019
Priority date	Jan 26, 2018
Publication date	Apr 27, 2021
Grant date	Apr 27, 2021

Abstract

To provide a glass composition which can be used for a dental porcelain or a dental ceramics coloring material, and has low temperature meltability, acid resistance and preservation stability under the humid environment which are required for a dental porcelain or a dental ceramics coloring material, and a dental porcelain and dental ceramics coloring material which contain the glass composition of the present disclosure. To provide a low melting glass composition with softening point (Ts) less than 600° C. comprising as a component; SiO2: 55.0 to 75.0 wt. %, B2O3: 6.1 to 12.0 wt. %, Al2O3: 2.0 to 8.0 wt. %, ZnO: 2.0 to 8.5 wt. % and two or more kinds of alkali metal oxide: 10.5 to 20.0 wt. %.

First claim

What is claimed is:

1. A low melting glass composition with a softening point (Ts) less than 600° C., which comprises:
SiO 2 : 55.0 to 75.0 wt. %,
B 2 O 3 : 6.1 to 12.0 wt. %,
Al 2 O 3 : 2.0 to 8.0 wt. %,
ZnO: 2.0 to 6.5 wt. %, and
two or more alkali metal oxides: 10.5 to 20.0 wt. %, wherein a thermal expansion coefficient at a temperature within a range of 25° C. to 400° C. based on ISO 6872:2015 is within a range of 7.0 to 11.0×10 −6 K −1 .

2. The low melting glass composition according to claim 1 , further comprising at least one selected from the group consisting of:
MgO: 3.0 wt. % or less,
CaO: 3.0 wt. % or less,
ZrO 2 : 4.0 wt. % or less,
TiO 2 : 3.0 wt. % or less, and
F: 2.0 wt. % or less.

3. The low melting glass composition according to claim 1 , wherein:
a dissolution amount to an acid based on ISO 6872:2015 is 35 μg/cm 2 or less.

4. A dental porcelain compounded with the low melting glass composition according to claim 1 .

5. A dental ceramics coloring material compounded with the low melting glass composition according to claim 1 .

6. The low melting glass composition according to claim 2 , wherein:
a dissolution amount to an acid based on ISO 6872:2015 is 35 μg/cm 2 or less.

7. A dental porcelain compounded with the low melting glass composition according to claim 2 .

8. A dental ceramics coloring material compounded with the low melting glass composition according to claim 2 .

9. A dental porcelain compounded with the low melting glass composition according to claim 3 .

10. A dental ceramics coloring material compounded with the low melting glass composition according to claim 3 .

Assignees

• Shofu Inc

Inventors

• Kawata Keita
• Goto Masanori
• Kono Kenji

Classifications

• A61K6/802

  comprising ceramics · CPC title

• C03C2205/06

  for dental use · CPC title

• C03C8/14

  Glass frit mixtures having non-frit additions, e.g. opacifiers, colorants, mill-additions · CPC title

• C03C4/0021 Primary

  for dental use · CPC title

• C03C3/093

  containing zinc or zirconium · CPC title