US4472332A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for the production of porous ceramic molded articles
Assignee: Toyo Tire Corp
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Filing: 1983-02-22
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Granted: 1984-09-18
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Expires: 2003-02-22
Abstract
Abstract A process for the production of a porous ceramic mold is described, compsiging adding about 40 to 60 parts by weight of water to 100 parts by weight of a ceramic material, mixing the thus-formed ceramic slurry with about 20 to 40 parts by weight of a hydrophilic urethane prepolymer having a free isocyanate group content of from about 4% to 7% by weight, reacting and foaming the resulting mixture after the introduction thereof into a mold, drying the thus-formed foamed urethane molded article, and combusting very slowly and sintering the dried foamed urethane molded article to produce a porous ceramic molded article.
Inventors
- 👤 Shigeyoshi Fukushima
- 👤 Masaaki Mizuno
- 👤 Hideaki Koga
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:55
CPC Classifications
B; B01; B01J; B01J20/00; B01J20/28; B01J20/28014; B01J20/28042; B01J20/28045; B01D; B01D39/00; B01D39/14; B01D39/20; B01D39/2068; B01D39/2093; B01J20/02; B01J20/0203; B01J20/0251; B01J20/06; B01J20/08; B01J20/10; B01J20/12; B01J20/30; B01J20/3007; B01J20/3078; B01J37/00; B01J37/0009; B01J37/0018; C; C04; C04B; C04B38/00; C04B38/06; C04B38/0615; C04B38/062; C04B38/0625
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
163 words
A process for producing a porous ceramic molded article comprising adding from about 40 to 60 parts by weight of water to 100 parts by weight of a ceramic material to prepare a ceramic slurry, adding to said slurry from about 20 to 40 parts by weight of a hydrophilic urethane prepolymer having a free isocyanate group content of from about 4% to 7% by weight, which is prepared by reacting an ethylene oxide-propylene oxide copolymer having an average molecular weight of from about 1,500 to 3,500 and an ethylene oxide content of from about 70% to 90% by weight and a polyisocyanate compound containing at least two isocyanate groups at the terminal portions thereof, introducing the resulting hydrophilic urethane prepolymer-ceramic slurry mixture into a mold, reacting and foaming the mixture to form a foamed urethane molded article, drying the thus-formed foamed urethane molded article, and combusting very slowly and sintering the foamed urethane molded article to produce a porous ceramic molded article.
Claim 2
Dependent Claim
163 words
A process for producing a porous ceramic molded article comprising adding from about 40 to 60 parts by weight of water to 100 parts by weight of a ceramic material to prepare a ceramic slurry, adding to said slurry from about 20 to 40 parts by weight of a hydrophilic urethane prepolymer having a free isocyanate group content of from about 4% to 7% by weight, which is prepared by reacting an ethylene oxide-propylene oxide copolymer having an average molecular weight of from about 1,500 to 3,500 and an ethylene oxide content of from about 70% to 90% by weight and a polyisocyanate compound containing at least two isocyanate groups at the terminal portions thereof, introducing the resulting hydrophilic urethane prepolymer-ceramic slurry mixture into a mold, reacting and foaming the mixture to form a foamed urethane molded article, drying the thus-formed foamed urethane molded article, and combusting very slowly and sintering the foamed urethane molded article to produce a porous ceramic molded article.
Claim 3
Dependent Claim
29 words
A process as in claim 1, wherein the ceramic material consists essentially of kaolin, clay, alumina, feldspar, pottery stone, mullite, zircon, zirconia, titania, silicon carbide, cordierite, or combinations thereof.
Claim 4
Dependent Claim
23 words
A process as in claim 1, wherein the ethylene oxide-propylene oxide copolymer has an average molecular weight of from about 2,500 to 3,000.
Claim 5
Dependent Claim
24 words
A process as in claim 1, wherein the weight ratio of the hydrophilic urethane prepolymer/water is within the range of from 33/100 to 100/100.
Claim 6
Dependent Claim
40 words
A process as in claim 1, wherein an open cell foaming agent is added to the hydrophilic urethane prepolymer in an amount of from about 1 to 2 parts by weight per 100 parts by weight of the ceramic material.
Claim 7
Dependent Claim
16 words
A process as in claim 1, wherein the open-cell foaming agent is polydimethyl siloxane-polyoxy alkylene copolymer.
Claim 8
Dependent Claim
21 words
A process as in claim 1, wherein the polyisocyanate compound is tolylenediisocyanate or a mixture of tolylenediisocyanate and other polyisocyanate compounds.
Claim 9
Dependent Claim
23 words
A process as in claim 1, wherein the dried urethane article is combusted with gradually heating at about 100° C. to 400° C.
References Cited (Backward Citations)
US3833386A
Cited
US3793237A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-09-18 | 1988-03-19 | 1988-09-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-09-18 | 1992-03-19 | 1992-09-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-09-18 | 1996-03-19 | 1996-09-18 | $7700.00 | Window Closed / Lapsed |