US4368180A
Expired / Lapsed
US
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Method for producing powder of α-silicon nitride
Assignee: SHIBAURA DENKI A CORP OF JAPAN KK
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Filing: 1981-08-17
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Granted: 1983-01-11
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Expires: 2001-08-17
Abstract
Abstract A method for producing powder of a α-silicon nitride which comprises the steps of adding 0.1 to 2 parts by weight of carbon and 0.005 to 1 part by weight of at least one silicon compound selected from the group consisting of Si 3 N 4 , SiC and Si 2 ON 2 to one part by weight, when converted to SiO 2 , of a liquid alkylchlorosilane that forms a precipitate and HCl by hydrolysis which precipitate is convertible to SiO 2 at a baking temperature of 1300° to 1550° C., hydrolyzing the resultant mixture, washing the mixture to separate a solid component, and baking the solid component at a temperature of 1300° to 1550° C. in an atmosphere mainly consisting of a nitrogen gas or a gas of a nitrogen compound to effect formation of α-silicon nitride.
Inventors
- 👤 Hiroshi Inoue
- 👤 Katsutoshi Komeya
- 👤 Akihiko Tsuge
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 06:33
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/515; C04B35/58; C04B35/584; C01; C01B; C01B21/00; C01B21/06; C01B21/068; C01B21/0685; C01P; C01P2004/00; C01P2004/60; C01P2004/61; C01P2006/00; C01P2006/80
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
138 words
A method for producing powder of α-silicon nitride which comprises the steps of: adding 0.1 to 2 parts by weight of carbon and 0.005 to 1 part by weight of at least one silicon compound selected from the group consisting of Si 3 N 4 , SiC and Si 2 ON 2 to 1 part by weight, when converted to SiO 2 , of a liquid alkylchlorosilane that forms a precipitate and HCl by hydrolysis which precipitate is convertible to SiO 2 at a baking temperature of 1300° to 1550° C.; hydrolyzing the resultant mixture; washing the mixture to separate a solid component; and baking the solid component at a temperature of 1300° to 1550° C. in an atmosphere mainly consisting of a nitrogen gas or a gas of a nitrogen compound to effect formation of α-silicon nitride.
Claim 2
Independent Claim
138 words
A method for producing powder of α-silicon nitride which comprises the steps of: adding 0.1 to 2 parts by weight of carbon and 0.005 to 1 part by weight of at least one silicon compound selected from the group consisting of Si 3 N 4 , SiC and Si 2 ON 2 to 1 part by weight, when converted to SiO 2 , of a liquid alkylchlorosilane that forms a precipitate and HCl by hydrolysis which precipitate is convertible to SiO 2 at a baking temperature of 1300° to 1550° C.; hydrolyzing the resultant mixture; washing the mixture to separate a solid component; and baking the solid component at a temperature of 1300° to 1550° C. in an atmosphere mainly consisting of a nitrogen gas or a gas of a nitrogen compound to effect formation of α-silicon nitride.
Claim 3
Independent Claim
136 words
A method for producing powder of α-silicon nitride which comprises the steps of: hydrolyzing a liquid alkyl-chlorosilane to form a precipitate and HCl, the precipitate being convertible to SiO 2 at a baking temperature of 1300° to 1550° C.; washing the hydrolyzed mass to separate a solid component; adding 0.1 to 2 parts by weight of carbon and 0.005 to 1 part by weight of at least one silicon compound selected from the group consisting of Si 3 N 4 , SiC and Si 2 ON 2 to one part by weight, when converted to SiO 2 , of said precipitate; and baking the resultant mixture at a temperature of 1300° to 1550° C. in an atmosphere mainly consisting of a nitrogen gas or a gas of a nitrogen compound to effect formation of α-silicon nitride.
Claim 4
Independent Claim
136 words
A method for producing powder of α-silicon nitride which comprises the steps of: hydrolyzing a liquid alkyl-chlorosilane to form a precipitate and HCl, the precipitate being convertible to SiO 2 at a baking temperature of 1300° to 1550° C.; washing the hydrolyzed mass to separate a solid component; adding 0.1 to 2 parts by weight of carbon and 0.005 to 1 part by weight of at least one silicon compound selected from the group consisting of Si 3 N 4 , SiC and Si 2 ON 2 to one part by weight, when converted to SiO 2 , of said precipitate; and baking the resultant mixture at a temperature of 1300° to 1550° C. in an atmosphere mainly consisting of a nitrogen gas or a gas of a nitrogen compound to effect formation of α-silicon nitride.
Claim 5
Dependent Claim
23 words
The method according to claim 1 or 2, further comprising a step of grinding the solid component or resultant mixture prior to baking.
Claim 6
Dependent Claim
25 words
The method according to claim 3, wherein the solid component or resultant mixture is ground to a powder particle size of 50 μm or less.
Claim 7
Dependent Claim
22 words
The method according to claim 3, wherein the carbon is added in an amount ranging from 0.1 to 0.3 part by weight.
Claim 8
Dependent Claim
13 words
The method according to claim 1 or 2, wherein the alkylchlorosilane is methyltrichlorosilane.
Claim 9
Dependent Claim
18 words
The method according to claim 1 or 2, wherein the alkylchlorosilane is a mixture of methyltrichlorosilane and dimethyldichlorosilane.
Claim 10
Dependent Claim
17 words
The method according to claim 1 or 2, wherein the nitrogen compound gas is NH 3 .
Claim 11
Dependent Claim
33 words
The method according to claim 1 or 2, wherein the solid component is thermally dehydrated at a temperature of 200° to 300° C., before baked at a temperature of 1300° to 1550° C.
Claim 12
Dependent Claim
37 words
The method according to claim 1 or 2, wherein the reaction product is baked at a temperature of 1300° to 1550° C. is again baked in an oxidizing atmosphere at a temperature of 600° to 800° C.
Claim 13
Dependent Claim
24 words
The method according to claim 1 or 2, wherein the carbon is added in an amount ranging from 0.4 to 1 part by weight.
Claim 14
Dependent Claim
25 words
The method according to claim 1 or 2, wherein the silicon compound is added in an amount ranging from 0.01 to 0.1 part by weight.
Claim 15
Dependent Claim
20 words
The method according to claim 1 or 2, wherein the carbon has a mean particle size smaller than 1 micron.
Claim 16
Dependent Claim
21 words
The method according to claim 1 or 2, wherein the silicon compound has a mean particle size smaller than 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) | 1986-01-10 | 1986-07-12 | 1987-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-01-10 | 1990-07-12 | 1991-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-01-10 | 1994-07-12 | 1995-01-11 | $7700.00 | Window Closed / Lapsed |