Patent US4568942A successfully refreshed from Google Patents.
US3590902A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Production of foundry cores and molds
Assignee: Foseco Fordath AG
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Filing: 1968-05-27
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Granted: 1971-07-06
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Expires: 1988-05-27
Abstract
Abstract A foundry core is prepared by coating said with a mixture of a novolac resin and a polyisocyanate the coated sand being introduced into a core box, mold or pattern and a volatile amine, such as triethylamine, passed into the core box, mold or pattern to obtain a rapid cure.
Inventors
- 👤 James Walker
- 👤 Geoffrey W Westwood
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 09:30
CPC Classifications
B; B22; B22C; B22C1/00; B22C1/16; B22C1/162; B22C1/20; B22C1/22; B22C1/2233; B22C1/2273; B22C9/00; B22C9/12; B22C9/123; C; C08; C08G; C08G18/00; C08G18/06; C08G18/08; C08G18/16; C08G18/18; C08G18/1891; C08G18/28; C08G18/40; C08G18/54; C08G18/542; C08G18/58
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
78 words
In a process for the production of foundry molds and cores wherein a mixture comprising a foundry aggregate and a binder including a novolac resin and a polyisocyanate are introduced into a core box, mold or pattern to form a green core or mold and an amine is passed into the core box, mold or pattern to effect curing of the core or mold, the improvement wherein said novolac resin is dissolved in an organic solvent comprising cyclohexanone.
Claim 2
Dependent Claim
78 words
In a process for the production of foundry molds and cores wherein a mixture comprising a foundry aggregate and a binder including a novolac resin and a polyisocyanate are introduced into a core box, mold or pattern to form a green core or mold and an amine is passed into the core box, mold or pattern to effect curing of the core or mold, the improvement wherein said novolac resin is dissolved in an organic solvent comprising cyclohexanone.
Claim 3
Dependent Claim
30 words
A process according to claim 1 in which the amine is passed into the core box, mold or pattern in the form of a vapor entrained in a gaseous carrier.
Claim 4
Dependent Claim
12 words
A process according to claim 2 in which the amine is triethylamine.
Claim 5
Dependent Claim
13 words
A process according to claim 1 in which the polyisocyanate is 4,4-diphenylmethane diisocyanate.
Claim 6
Dependent Claim
29 words
A process according to claim 1 in which the solution of the novolac resin in said solvent has a solids content of between 20 and 60 percent by weight.
Claim 7
Dependent Claim
29 words
A process according to claim 5 in which the solution of the novolac resin in said solvent has a solids content of between 25 and 50 percent by weight.
Claim 8
Dependent Claim
26 words
A process according to claim 6 in which the solution of the novolac resin has a solids content of between 35 and 45 percent by weight.
Claim 9
Dependent Claim
31 words
A process according to claim 1 in which the amount by weight of novolac resin in the aggregate/resin/polyisocyanate mixture is between 0.25 and 5 percent of the weight of the aggregate.
Claim 10
Dependent Claim
30 words
A process according to claim 1 in which the amount by weight of polyisocyanate in the aggregate/resin/polyisocyanate mixture is between 0.25 and 5 percent of the weight of the aggregate.
Claim 11
Dependent Claim
30 words
A process according to claim 1 in which the novolac resin is a phenolformaldehyde resin having a molar ratio of phenol to formaldehyde of 1 to between 0.55 and 0.9.
Claim 12
Dependent Claim
26 words
A process according to claim 10 in which the molar ratio of phenol to formaldehyde of the novolac resin is 1 to between 0.6 and 0.75.
Claim 13
Dependent Claim
18 words
A process according to claim 1 in which the novolac resin is admixed with a phenolformaldehyde resole resin.
Claim 14
Dependent Claim
18 words
A process according to claim 1 in which the novolac resin is admixed with a material containing polypentaerythritol.
Claim 15
Dependent Claim
46 words
A process according to claim 1 in which the ratio of the amount by weight of novolac resin in the foundry aggregate/resin/polyisocyanate mixture to the amount by weight of polyisocyanate in said mixture is within the range of 1 to from about 0.9 to about 1.35.
Claim 16
Dependent Claim
38 words
A process according to claim 1 in which the novolac resin is a phenolformaldehyde resin dissolved in an organic solvent comprising cyclohexanone and at least one member selected from the group consisting of methoxyhexanone, isophorone, xylene and chlorobenzen.
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) | 1974-07-05 | 1975-01-04 | 1975-07-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-05 | 1979-01-04 | 1979-07-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-05 | 1983-01-04 | 1983-07-06 | $7700.00 | Window Closed / Lapsed |