US4734237A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for injection molding ceramic composition employing an agaroid gell-forming material to add green strength to a preform
Assignee: Honeywell International Inc
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Filing: 1986-05-15
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Granted: 1988-03-29
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Expires: 2006-05-15
Abstract
Abstract A process for shaping parts from metallic and/or ceramic powders is disclosed. The process comprises the steps of forming a mixture comprising metal and/or ceramic powders, a gel-forming material having a gel strength, measured at a temperature between 0° C. and about 22° C. and a gel consisting essentially of about 4 wt. % of the gel-forming material and water, of at least about 100 g/cm 2 , and a gel-forming material solvent, and molding the mixture at a temperature sufficient to produce a self-supporting article comprising the powder and a gel. The preferred gel-forming material is an agaroid and the preferred molding process is injection molding.
Inventors
- 👤 Anthony J. Fanelli
- 👤 Robert D. Silvers
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:12
CPC Classifications
B; B22; B22F; B22F3/00; B22F3/22; B22F3/225; C; C04; C04B; C04B35/00; C04B35/01; C04B35/10; C04B35/111; C04B35/50; C04B35/505; C04B35/622; C04B35/626; C04B35/63; C04B35/632; C04B35/634; C04B35/636; B22F2998/00
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
176 words
A method of forming an article comprising the steps of: (a) forming a mixture comprising (1) powders selected from the group consisting of metal powders, ceramic powders, and mixtures thereof, (2) an agaroid gel-forming material having a gel strength, measured at a temperature between 0° C. and about 22° C. on a gel consisting essentially of about 4 wt % of the agaroid gel-forming material and water, of at least about 500 g/cm 2 , and (3) an agaroid gel-forming material solvent; (b) heating the mixture to a first temperature above the gel point of the agaroid gel-forming material to solubilize the agaroid gel-forming material, said first temperature being in the range from 80° C. to 100° C.; (c) supplying the mixture to a mold; and (d) molding the mixture at a second, cooler temperature at or below the gel point of the agaroid gel-forming material to produce a self-supporting article comprising the powders and a gel comprising the agaroid gel-forming material, said second, cooler temperature being in the range from 15° C. to 45° C.
Claim 2
Independent Claim
176 words
A method of forming an article comprising the steps of: (a) forming a mixture comprising (1) powders selected from the group consisting of metal powders, ceramic powders, and mixtures thereof, (2) an agaroid gel-forming material having a gel strength, measured at a temperature between 0° C. and about 22° C. on a gel consisting essentially of about 4 wt % of the agaroid gel-forming material and water, of at least about 500 g/cm 2 , and (3) an agaroid gel-forming material solvent; (b) heating the mixture to a first temperature above the gel point of the agaroid gel-forming material to solubilize the agaroid gel-forming material, said first temperature being in the range from 80° C. to 100° C.; (c) supplying the mixture to a mold; and (d) molding the mixture at a second, cooler temperature at or below the gel point of the agaroid gel-forming material to produce a self-supporting article comprising the powders and a gel comprising the agaroid gel-forming material, said second, cooler temperature being in the range from 15° C. to 45° C.
Claim 3
Dependent Claim
20 words
The method of claim 1 wherein the powders comprise between about 50% to about 90% (by weight) of the mixture.
Claim 4
Dependent Claim
22 words
The method of claim 1 wherein the gel forming material comprises between about 0.2% and about 6% by weight of the mixture.
Claim 5
Dependent Claim
30 words
The method of claim 1 further comprising the step of maintaining the mixture at a temperature above the gel point of the gel-forming material prior to the molding step (b).
Claim 6
Dependent Claim
12 words
The method of claim 3 wherein the mixture further comprises a glycol.
Claim 7
Dependent Claim
31 words
The method of claim 5 wherein the glycol is present in an amount up to about 10% by weight of the gel-forming material and the gel forming solvent in the mixture.
Claim 8
Dependent Claim
15 words
The method of claim 1 wherein the agaroid is agar, agarose, or a mixture thereof.
Claim 9
Dependent Claim
15 words
The method of claim 3 wherein the agaroid is agar, agarose, or a mixture thereof.
Claim 10
Dependent Claim
175 words
An injection molding process comprising the steps of: (a) forming a mixture comprising (1) powders selected from the groups of metal powders, ceramic powders and mixtures thereof, (2) an agaroid gel-forming material having a gel strength, measured at a temperature between O° C. about 22° C. on a gel consisting essentially of about 4 wt % of the agaroid gel forming material and water, of at least about 500 g/cm 2 , (3) an agaroid gel-forming material solvent, and (4) a carrier; (b) injecting the mixture into a mold, the mixture being maintained prior to the injection step at a first temperature above the gel point of the agaroid gel-forming material, said first temperature being in the range from 80° C. to 100° C.; and, (c) cooling the mixture in the mold to a second temperature below the gel point of the agaroid gel-forming material to form a self supporting article comprising the powders and a gel comprising the agaroid gel-forming material, said second temperature being in the range from 15° C. to 45° C.
Claim 11
Dependent Claim
175 words
An injection molding process comprising the steps of: (a) forming a mixture comprising (1) powders selected from the groups of metal powders, ceramic powders and mixtures thereof, (2) an agaroid gel-forming material having a gel strength, measured at a temperature between O° C. about 22° C. on a gel consisting essentially of about 4 wt % of the agaroid gel forming material and water, of at least about 500 g/cm 2 , (3) an agaroid gel-forming material solvent, and (4) a carrier; (b) injecting the mixture into a mold, the mixture being maintained prior to the injection step at a first temperature above the gel point of the agaroid gel-forming material, said first temperature being in the range from 80° C. to 100° C.; and, (c) cooling the mixture in the mold to a second temperature below the gel point of the agaroid gel-forming material to form a self supporting article comprising the powders and a gel comprising the agaroid gel-forming material, said second temperature being in the range from 15° C. to 45° C.
Claim 12
Dependent Claim
74 words
The process of claim 9 wherein the powders are present in the mixture in an amount between about 50% and about 90% by weight of the mixture, the gel forming agent is present in the mixture in an amount between about 0.2 and about 6% by weight of the mixture, and the solvent is present in an amount sufficient to dissolve the gel-forming material at the first temperature and to function as the carrier.
Claim 13
Dependent Claim
12 words
The process of claim 9 wherein the mixture further comprises a glycol.
Claim 14
Dependent Claim
30 words
The process of claim 11 wherein the glycol is present in an amount up to about 10% by weight of the gel forming material and the solvent in the mixture.
Claim 15
Dependent Claim
15 words
The method of claim 9 wherein the agaroid is agar, agarose, or a mixture thereof.
Claim 16
Dependent Claim
67 words
A composition of matter comprising powder selected from the group consisting of metal powder, ceramic powder and mixtures thereof and, mixed therewith, an agaroid gel-forming material having a gel strength, measured at a temperature between 0° C. and about 22° C. on a gel consisting essentially of about 4 wt % of the agaroid gel forming material and water, of at least about 500 g/cm 2 .
Claim 17
Dependent Claim
67 words
A composition of matter comprising powder selected from the group consisting of metal powder, ceramic powder and mixtures thereof and, mixed therewith, an agaroid gel-forming material having a gel strength, measured at a temperature between 0° C. and about 22° C. on a gel consisting essentially of about 4 wt % of the agaroid gel forming material and water, of at least about 500 g/cm 2 .
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) | 1991-03-29 | 1991-09-28 | 1992-03-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-03-29 | 1995-09-28 | 1996-03-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-03-29 | 1999-09-28 | 2000-03-29 | $7700.00 | Window Closed / Lapsed |