US4154717A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydraulic dental cement composition
Assignee: Sankin Industry Co Ltd
•
Filing: 1977-10-13
•
Granted: 1979-05-15
•
Expires: 1997-10-13
Abstract
Abstract A hydraulic dental cement composition which comprises a mixture of a dental cement powder having silicon oxide for its essential constituent and a setting agent powder having polyacrylic acid for its essential constituent is disclosed. This composition is of high compression strength due to the silicon dioxide contained therein, and its own pulverulence makes it excellent in workability because it has only to be kneaded with water to be placed into a useable form. Addition of zinc oxide or the like enhances the resistance to deterioration of the composition.
Inventors
- 👤 Tamotsu Kohmura
- 👤 Hiroshi Nakanaga
- 👤 Kazuhiro Ida
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 23:40
CPC Classifications
A; A61; A61K; A61K6/00; A61K6/80; A61K6/884; A61K6/887; A61K6/889
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
76 words
A hydraulic dental cement composition comprising a mixture of a dental cement powder containing from 18 to 70% by weight silicon oxide, from 9.8 to 82% by weight zinc oxide and at least one additional component selected from the group consisting of from 5 to 20% by weight aluminum oxide, from 5 to 50% by weight inorganic fluoride and from 5 to 15% by weight of aluminum phosphate; and a setting agent powder containing polyacrylic acid.
Claim 2
Dependent Claim
76 words
A hydraulic dental cement composition comprising a mixture of a dental cement powder containing from 18 to 70% by weight silicon oxide, from 9.8 to 82% by weight zinc oxide and at least one additional component selected from the group consisting of from 5 to 20% by weight aluminum oxide, from 5 to 50% by weight inorganic fluoride and from 5 to 15% by weight of aluminum phosphate; and a setting agent powder containing polyacrylic acid.
Claim 3
Dependent Claim
49 words
The composition of claim 1, wherein said dental cement powder containing silicon oxide is composed of the following ingredients: silicon oxide: 18-70% by weight zinc oxide: 9.8-82% by weight aluminum oxide: 5-20% by weight inorganic fluoride: 5-50% by weight aluminum phosphate: 5-15% by weight magnesium oxide: 5-15% by weight.
Claim 4
Dependent Claim
46 words
The composition of claim 1, wherein said dental cement powder is obtained by sintering a mixture of all said ingredients at a temperature of from 1000° to 1250° C. for at least one hour and by fine-crushing said mixture into grains of smaller than 350 mesh.
Claim 5
Dependent Claim
19 words
The composition of claim 1, wherein said dental cement powder is obtained by being fine-ground by being jet sprayed.
Claim 6
Dependent Claim
20 words
The composition of claim 1, wherein said setting agent powder contains a homopolymer of acrylic acid as its principal ingredient.
Claim 7
Dependent Claim
47 words
The composition of claim 1, wherein said setting agent powder contains a copolymer of acrylic acid with at least one member selected from the group consisting of lower (C 1 -C 6 ) alkyl acrylate, lower (C 1 -C 6 ) alkyl methacrylate, and unsaturated carboxylic acid.
Claim 8
Dependent Claim
36 words
The composition of claim 7, wherein said unsaturated carboxylic acid is at least one member selected from the group consisting of maleic acid, aconitic acid, fumaric acid, citraconic acid, mesaconic acid, itaconic acid, and methacrylic acid.
Claim 9
Dependent Claim
20 words
The composition of claim 1, wherein said setting agent powder comprises a polymer of 40 to 300 degrees of polymerization.
Claim 10
Dependent Claim
15 words
The composition of claim 1, wherein said setting agent powder contains less than 10% moisture.
Claim 11
Dependent Claim
21 words
The composition of claim 1, wherein the compounding ratio of said dental cement powder to said setting agent powder is 95-50:5-50.
Claim 12
Dependent Claim
47 words
A hydraulic dental cement composition comprising a mixture of a dental cement powder containing from 18 to 70% by weight silicon oxide, from 9.8 to 82% by weight zinc oxide and from 5 to 20% by weight aluminum oxide; and a setting agent powder containing polyacrylic acid.
Claim 13
Dependent Claim
47 words
A hydraulic dental cement composition comprising a mixture of a dental cement powder containing from 18 to 70% by weight silicon oxide, from 9.8 to 82% by weight zinc oxide and from 5 to 20% by weight aluminum oxide; and a setting agent powder containing polyacrylic acid.
Claim 14
Dependent Claim
47 words
The composition of claim 11, wherein said dental cement powder contains at least one additional component selected from the group consisting of from 5 to 50% by weight inorganic fluoride, from 5 to 15 by weight aluminum phosphate and from 5 to 15% by weight magnesium oxide.
References Cited (Backward Citations)
GB1316129A
Cited
US3741926A
Cited
US3751391A
Cited
US4016124A
Cited
US4017454A
Cited
US3962267A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-05-14 | 1982-11-13 | 1983-05-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-05-14 | 1986-11-13 | 1987-05-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-05-14 | 1990-11-13 | 1991-05-15 | $7700.00 | Window Closed / Lapsed |