US5238627A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for producing ceramics sintered article and molding method and molding apparatus to be used therefor
Assignee: NGK Insulators Ltd
•
Filing: 1990-12-06
•
Granted: 1993-08-24
•
Expires: 2010-12-06
Abstract
Abstract A ceramics shaped article having a large wall-thickness and having a complicated shape, which can not be monolithically produced by a conventional molding, can be easily produced through a monolithical molding by the use of a ceramic batch containing water as a plasticizing medium and a small amount of an organic binder as a plasticizer. The ceramic shaped article can be fired into a ceramic sintered article in high dimensional accuracy and yield.
Inventors
- 👤 Tadaaki Matsuhisa
- 👤 Shigeki Kato
- 👤 Hiroyuki Iwasaki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 20:11
CPC Classifications
B; B28; B28B; B28B1/00; B28B1/26; B28B1/261; B28B1/24; B28B1/265; B28B17/00; B28B17/02; B28B17/026; B28B7/00; B28B7/34; B28B7/344; C; C04; C04B; C04B35/00; C04B35/622; C04B35/626; C04B35/63; C04B35/632; C04B35/64
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
78 words
A method of producing ceramic articles sequentially comprising the steps of: (a) injection molding a kneaded material containing ceramic powder, sintering aids, water and organic binder to provide a molded body, said ceramic powder having a particle size within a range defined by the following formula: ##EQU3## (b) drying the molded body; (c) isostatically pressing the entire dried, molded body under hydrostatic pressure; (d) removing the organic binder from the molded body; and (e) sintering the molded body.
Claim 2
Independent Claim
78 words
A method of producing ceramic articles sequentially comprising the steps of: (a) injection molding a kneaded material containing ceramic powder, sintering aids, water and organic binder to provide a molded body, said ceramic powder having a particle size within a range defined by the following formula: ##EQU3## (b) drying the molded body; (c) isostatically pressing the entire dried, molded body under hydrostatic pressure; (d) removing the organic binder from the molded body; and (e) sintering the molded body.
Claim 3
Dependent Claim
29 words
The method of claim 1, wherein the ceramic powder comprises at least one component selected from the group consisting of silicon carbide, silicon nitride, sialon, boron nitride, and zirconia.
Claim 4
Dependent Claim
23 words
The method of claim 1, wherein the sintering aids are used in the form of particles similar to that of the ceramic powder.
Claim 5
Dependent Claim
33 words
The method of claim 1, wherein the water is added to the ceramic powder as a plasticizer in an amount of 10-50 parts by weight to 100 parts by weight of ceramic powder.
Claim 6
Dependent Claim
47 words
The method of claim 1, wherein the organic binder comprises a water soluble or water absorbable organic compound selected from the group consisting of methyl cellulose, hydroxy propyl methyl cellulose or other water soluble cellulose ether derivatives; polyvinyl alcohol, polyethylene glycol or other water absorbable high polymers.
Claim 7
Dependent Claim
33 words
The method of claim 1, wherein the organic binder has thermo-gelling and setting properties, and is selected from the group consisting of methyl cellulose, hydroxy propyl methyl cellulose, and alkylene oxide cellulose derivatives.
Claim 8
Dependent Claim
31 words
The method of claim 1, wherein the organic binder is contained in the kneaded material in an amount of 0.1-15 parts by weight to 100 parts by weight of ceramic powder.
Claim 9
Dependent Claim
33 words
The method of claim 1, wherein the ceramic powder is previously mixed with the sintering aids and the mixture of the ceramic powder and sintering aids is ground to provide a ground mixture.
Claim 10
Dependent Claim
15 words
The method of claim 8, wherein the ground mixture is dried by a spray dryer.
Claim 11
Dependent Claim
15 words
The method of claim 1, wherein the hydrostatic pressure is about 1˜10 ton/cm 2 .
Claim 12
Dependent Claim
15 words
The method of claim 1, wherein the hydrostatic pressure is about 2.5˜8 ton/cm 2 .
Claim 13
Dependent Claim
13 words
The method of claim 1, wherein the sintering aids comprise rare earth oxides.
Claim 14
Dependent Claim
30 words
The method of claim 1, wherein the sintering aids comprise at least one component selected from the group consisting of magnesia, beryllia, cerium oxide, strontium oxide, titania, zirconia and yttria.
Claim 15
Dependent Claim
26 words
The method of claim 1, wherein the sintering aids comprise at least one composite oxide selected from the group consisting of beryllium titanate and zirconia titanate.
Claim 16
Dependent Claim
25 words
The method of claim 1, wherein the sintering aids comprise at least one multi-compositional oxide selected from the group consisting of mullite and aluminum zircon.
Claim 17
Independent Claim
94 words
A method for producing a ceramic sintered article, comprising the steps of: providing a ceramic powder having a particle size satisfying the following equation: ##EQU4## forming a mixture of said ceramic powder with a sintering aid, water and an organic binder; deaerating the mixture by means of a vacuum kneading machine to produce a ceramic batch; injection molding the ceramic batch into an injection molding die to form a green shaped article; removing the water and organic binder from the green shaped article; and firing the shaped article to form said ceramic sintered article.
Claim 18
Independent Claim
94 words
A method for producing a ceramic sintered article, comprising the steps of: providing a ceramic powder having a particle size satisfying the following equation: ##EQU4## forming a mixture of said ceramic powder with a sintering aid, water and an organic binder; deaerating the mixture by means of a vacuum kneading machine to produce a ceramic batch; injection molding the ceramic batch into an injection molding die to form a green shaped article; removing the water and organic binder from the green shaped article; and firing the shaped article to form said ceramic sintered article.
Claim 19
Dependent Claim
61 words
The method of claim 16, further comprising the step of heating the injection molding die within a temperature range defied by T-10° C.≦T≦T+25° C., wherein T is the thermal gelation and curing temperature of the organic binder contained in the ceramic batch, to thermally elate and cure the organic binder and thus maintain the molded shape of the green shaped article.
References Cited (Backward Citations)
FR1059585A
Cited
US2893102A
Cited
US4341725A
Cited
JPS57146607A
Cited
US4429051A
Cited
EP0140682A1
Cited
EP0161494A1
Cited
US4677082A
Cited
US4734237A
Cited
US4923652A
Cited
JPS63236605A
Cited
EP0300681A1
Cited
DE3942666A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1996-08-23 | 1997-02-22 | 1997-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2000-08-23 | 2001-02-22 | 2001-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2004-08-23 | 2005-02-22 | 2005-08-24 | $7700.00 | Window Closed / Lapsed |