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US4480045A
Expired / Lapsed
US
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Alumina-based ceramic composition and substrate obtained by means of this composition
Assignee: CICE SA SA
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Filing: 1984-03-14
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Granted: 1984-10-30
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Expires: 2004-03-14
Abstract
Abstract Ceramic composition containing alumina, a deflocculating agent and at least one organic binder. According to the invention it is constituted, in dry extract form, by 95 to 99% by weight of a mixture of a first alumina of grain size below 2 microns, which can be fritted at a temperature below 1600 DEG C. for a bulk density below 2.3 and a second alumina of grain size below 3 microns, which can be fritted at a temperature below 1650 DEG C. for a bulk density below 2.4 and 1 to 5% by weight of organic products containing at least one deflocculating agent and at least one binder chosen from among the alkyl polyacrylates and their copolymers.
Inventors
- 👤 Yves Gougouyan
- 👤 Philippe Basseville
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 00:45
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/622; C04B35/626; C04B35/63; C04B35/632; C04B35/634; C04B35/63404; C04B35/63416; C04B35/01; C04B35/10; C04B35/111; C04B35/63424; H; H10; H10W; H10W70/00; H10W70/60; H10W70/67; H10W70/69; H10W70/692; H10W99/00
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
286 words
A process for producing a ceramic substrate for electronic components provided with holes, said substrate having a roughness of less than 10 microinch, comprising the steps of: (1) Mixing in an aqueous medium to form a composition of from about 97 to 98.5 percent by weight of a mixture of: (a) from about 65 to 95 percent by weight of a first alumina material having a grain size of from about 0.4 to 0.8 micron and a density of from about 2 to 2.20 which has been fired at a temperature of from about 1450° C. to 1580° C. to produce an alumina material having a density after firing of from about 3.85 to 3.96; and (b) From about 34 to 5 percent by weight of a second alumina material having a grain size of from about 1.2 to 1.6 microns and a density of from about 2.2 to 2.3 which has been fired at a temperature of from about 1580° C. to 1650° C. to produce an alumina material having a density of from about 3.85 to 3.96; and (c) From about 1.5 to 3 percent by weight of organic compounds comprising a deflocculating agent and an organic binder selected from the group consisting of butyl polyacrylates and copolymers thereof; (2) Atomizing said composition; (3) Screening the resulting composition to produce a granulated material having a grain size of from about 80 to 250 microns; (4) Mechanically compressing said composition in a mold to produce an unfired substrate having holes to conform to the desired configuration of said substrate; (5) Firing said substrate at a temperature of about 1580° C.; and (6) Auto-polishing a plurality of said so fired substrates in the presence of water.
Claim 2
Dependent Claim
286 words
A process for producing a ceramic substrate for electronic components provided with holes, said substrate having a roughness of less than 10 microinch, comprising the steps of: (1) Mixing in an aqueous medium to form a composition of from about 97 to 98.5 percent by weight of a mixture of: (a) from about 65 to 95 percent by weight of a first alumina material having a grain size of from about 0.4 to 0.8 micron and a density of from about 2 to 2.20 which has been fired at a temperature of from about 1450° C. to 1580° C. to produce an alumina material having a density after firing of from about 3.85 to 3.96; and (b) From about 34 to 5 percent by weight of a second alumina material having a grain size of from about 1.2 to 1.6 microns and a density of from about 2.2 to 2.3 which has been fired at a temperature of from about 1580° C. to 1650° C. to produce an alumina material having a density of from about 3.85 to 3.96; and (c) From about 1.5 to 3 percent by weight of organic compounds comprising a deflocculating agent and an organic binder selected from the group consisting of butyl polyacrylates and copolymers thereof; (2) Atomizing said composition; (3) Screening the resulting composition to produce a granulated material having a grain size of from about 80 to 250 microns; (4) Mechanically compressing said composition in a mold to produce an unfired substrate having holes to conform to the desired configuration of said substrate; (5) Firing said substrate at a temperature of about 1580° C.; and (6) Auto-polishing a plurality of said so fired substrates in the presence of water.
Claim 3
Dependent Claim
33 words
A process according to claim 1, wherein the mixture of alumina comprises from about 70 to 80% by weight of the first alumina and 30 to 20% by weight of the second alumina.
Claim 4
Dependent Claim
42 words
A process according to claim 2, which further comprises the steps of adding during mixing in aqueous medium from about 0 to 5% by weight of the ceramic composition in dry extract form, mineral products having a grain size below 2 microns.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-10-30 | 1988-04-30 | 1988-10-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-10-30 | 1992-04-30 | 1992-10-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-10-30 | 1996-04-30 | 1996-10-30 | $7700.00 | Window Closed / Lapsed |