US3725333A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for producing foundry molds and foundry molding compositions
Assignee: Hexion Inc
•
Filing: 1970-04-20
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Granted: 1973-04-03
•
Expires: 1990-04-20
Abstract
Abstract Foundry molding composition is prepared by mixing a granular refractory material, such as sand, with a curing agent and a phenol-formaldehyde resin binder which has been modified with 1070 percent, based on the weight of the resin, of furfural or furfuryl alcohol. The molding composition is blown into a pattern box preheated to 350*-600*F and cures in less than 60 seconds. The molds prepared from this molding composition demonstrate good resistance to water pick-up, have higher initial tensile strengths, much better retained strengths and do not impart pinholing effect to the castings manufactured therewith.
Inventors
- 👤 W Adkins
- 👤 T Bauer
- 👤 J Beane
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 14:19
CPC Classifications
B; B22; B22C; B22C1/00; B22C1/16; B22C1/20; B22C1/22; B22C1/2233; B22C1/224
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
26 words
Method of claim 1 wherein said curing agent includes 7 to 25 percent chromium nitrate, 15 to 45 percent urea, and 30 to 48 percent water.
References Cited (Backward Citations)
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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) | 1976-04-02 | 1976-10-02 | 1977-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-02 | 1980-10-02 | 1981-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-02 | 1984-10-02 | 1985-04-03 | $7700.00 | Window Closed / Lapsed |