US4329177A
Expired / Lapsed
US
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Alkali metal silicate binder compositions
Assignee: Foseco International Ltd
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Filing: 1980-02-19
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Granted: 1982-05-11
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Expires: 2000-02-19
Abstract
Abstract A binder composition in aqueous solution, suitable for use in the production of foundry sand moulds and cores is obtained by mixing (i) an alkali metal silicate (ii) a substantially water soluble carbohydrate selected from monosaccharides, disaccharides, polysaccharides and derivatives thereof and (iii) urea. The composition may also contain an oxyanion such as a borate which is capable of forming a water soluble complex with the carbohydrate. The preferred carbohydrate is a stabilized starch hydrolysate whose reducing power has been removed by a process such as hydrogenation. Moulds and cores bonded using the composition may be hardened by injection of carbon dioxide gas, or a chemical hardening agent for the alkali metal silicate may be added to the sand.
Inventors
- 👤 Raymond D. George
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 03:15
CPC Classifications
C; C04; C04B; C04B28/00; C04B28/24; C04B28/26; B; B22; B22C; B22C1/00; B22C1/16; B22C1/167; B22C1/20; B22C1/26
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
27 words
In a binder composition obtained by mixing, in aqueous solution, an alkali metal silicate and a hydrogenated starch hydrolysate, the improvement comprising including urea in said composition.
Claim 2
Dependent Claim
27 words
In a binder composition obtained by mixing, in aqueous solution, an alkali metal silicate and a hydrogenated starch hydrolysate, the improvement comprising including urea in said composition.
Claim 3
Dependent Claim
34 words
A binder composition according to claim 1 characterised in that it contains 15-47% by weight of alkali metal silicate, 2-45% by weight of the starch hydrolysate, 0.1-10% by weight of urea and balance water.
Claim 4
Dependent Claim
34 words
A binder composition according to claim 1 characterised in that it contains 26-45% by weight of alkali metal silicate, 3-27% by weight of the starch hydrolysate, 0.4-4% by weight of urea and balance water.
Claim 5
Dependent Claim
20 words
A binder composition according to any one of claims 1 to 3 characterised in that it also contains furfuryl alcohol.
Claim 6
Dependent Claim
19 words
A binder composition according to any one of claims 1 to 3 characterised in that it also contains formaldehyde.
Claim 7
Dependent Claim
22 words
A binder composition according to any one of claims 1 to 3 characterised in that the alkali metal silicate is sodium silicate.
Claim 8
Dependent Claim
51 words
In a method of making an article of bonded particulate material which comprises forming to the desired shape a mixture comprising particulate material and a binder, and causing or allowing the mixture to harden; the improvement comprising, as the binder, the composition according to any one of claims 1 to 3.
Claim 9
Dependent Claim
39 words
In a binder composition obtained by mixing, in aqueous solution, an alkali metal silicate, a substantially water soluble carbohydrate selected from monosaccharides, disaccharides, polysaccharides and derivatives thereof and an oxyanion salt, the improvement comprising including urea in said composition.
Claim 10
Dependent Claim
39 words
In a binder composition obtained by mixing, in aqueous solution, an alkali metal silicate, a substantially water soluble carbohydrate selected from monosaccharides, disaccharides, polysaccharides and derivatives thereof and an oxyanion salt, the improvement comprising including urea in said composition.
Claim 11
Dependent Claim
37 words
A binder composition according to claim 8 characterised in that it contains 15-47% by weight of alkali metal silicate, 2-45% by weight of carbohydrate, 0.5-5% by weight oxyanion salt, 0.1-10% by weight of urea and balance water.
Claim 12
Dependent Claim
37 words
A binder composition according to claim 8 characterised in that it contains 26-45% by weight of alkali metal silicate, 3-27% by weight of carbohydrate, 0.5-2% by weight oxyanion salt, 0.4-4% by weight of urea and balance water.
Claim 13
Dependent Claim
20 words
A binder composition according to any one of claims 8 to 10 characterised in that it also contains furfuryl alcohol.
Claim 14
Dependent Claim
19 words
A binder composition according to any one of claims 8 to 10 characterised in that it also contains formaldehyde.
Claim 15
Dependent Claim
22 words
A binder composition according to any one of claims 8 to 10 characterised in that the alkali metal silicate is sodium silicate.
Claim 16
Dependent Claim
23 words
A binder composition according to any one of claims 8 to 10 characterised in that the oxyanion salt is an alkali metal borate.
Claim 17
Dependent Claim
25 words
A binder composition according to any one of claims 8 to 10 characterised in that the carbohydrate is a monosaccharide selected from glucose and fructose.
Claim 18
Dependent Claim
26 words
A binder composition according to any one of claims 8 to 10 characterised in that the carbohydrate is a disaccharide selected from sucrose, maltose and lactose.
Claim 19
Dependent Claim
22 words
A binder composition according to any one of claims 8 to 10 characterised in that the carbohydrate is a hydrogenated starch hydrolysate.
Claim 20
Dependent Claim
51 words
In a method of making an article of bonded particulate material which comprises forming to the desired shape a mixture comprising particulate material and a binder, and causing or allowing the mixture to harden; the improvement comprising, as the binder, the composition according to any one of claims 8 to 10.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-05-10 | 1985-11-09 | 1986-05-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-05-10 | 1989-11-09 | 1990-05-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-05-10 | 1993-11-09 | 1994-05-11 | $7700.00 | Window Closed / Lapsed |