Patent US3801334A successfully refreshed from Google Patents.
US3801334A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Salt casting mixtures
Assignee: Individual
•
Filing: 1972-09-25
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Granted: 1974-04-02
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Expires: 1992-09-25
Abstract
Abstract Alkali metal nitrates and nitrites are useful as core material for making disposable cores, mandrels and other forms for use in making hollow plastic articles. The improvement discloses adding Portland cement as a method for improving the structural strength of such cores while providing a long storage life.
Inventors
- 👤 F Dewey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 12:12
CPC Classifications
B; B29; B29C; B29C33/00; B29C33/44; B29C33/52
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
15 words
The improvement as set forth in claim 1 wherein the Portland cement is type 1.
Claim 2
Dependent Claim
15 words
The improvement as set forth in claim 1 wherein the Portland cement is type 2.
Claim 3
Dependent Claim
27 words
The improvement as set forth in claim 1 wherein the amount of Portland cement is from about 15 percent by weight to about 43 percent by Weight.
Claim 4
Dependent Claim
48 words
A temperature stable water soluble disposable mandrel or relatively high compressive strength made from a material comprising a mixture of salts of the group consisting of sodium nitrate, sodium nitrite and potassium nitrate and a sufficient amount of Portland cement to stabilize the melting temperature of said mixture.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-04-01 | 1977-10-01 | 1978-04-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-01 | 1981-10-01 | 1982-04-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-01 | 1985-10-01 | 1986-04-02 | $7700.00 | Window Closed / Lapsed |