US2956038A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Erasable graphitic writing solution
Assignee: Venus Pen and Pencil Corp
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Filing: 1958-12-12
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Granted: 1960-10-11
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Expires: 1978-12-12
Abstract
No abstract record available.
Inventors
- 👤 Juelss David
- 👤 Torok Andrew
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:33
CPC Classifications
C; C09; C09D; C09D11/00; C09D11/16; C09D11/18; Y; Y10; Y10S; Y10S260/00; Y10S260/38
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
100 words
AN ERASABLE GRAPHIC WRITING FLUID COMPRISING A MINERAL OIL CARRIER, COLLOIDAL GRAPHITE DISPERSED IN SAID CARRIER, AND DISSOLVED IN SAID CARRIER, THE RESINOUS POLYMERIZATION PRODUCT OBTAINED BY CATALYTIC POLYMERIZATION OF A MIXTURE OF UNSATURATED MONOMERS DERIVED FROM DEEP CRACKING PETROLEUM, SAID RESINOUS POLYMERIZATION PRODUCT HAVING A SOFTENING POINT (B. & R.) WITHIN THE RANGE OF APPROXIMATELY 70 TO 100*C. A SPECIFIC GRAVITY AT 25* C. OF .970 TO .975, A REFRACTIVE INDEX AT 20*C. OF 1.5116, AN ACID NUMBER LESS THAN ONE, AN IODINE VALUE (WIJS) OF 120, A BROMINE NUMBER OF 7.3 AND A MOLECULAR WEIGHT OF APPROXIMATELY 1100.
Claim 2
Dependent Claim
100 words
AN ERASABLE GRAPHIC WRITING FLUID COMPRISING A MINERAL OIL CARRIER, COLLOIDAL GRAPHITE DISPERSED IN SAID CARRIER, AND DISSOLVED IN SAID CARRIER, THE RESINOUS POLYMERIZATION PRODUCT OBTAINED BY CATALYTIC POLYMERIZATION OF A MIXTURE OF UNSATURATED MONOMERS DERIVED FROM DEEP CRACKING PETROLEUM, SAID RESINOUS POLYMERIZATION PRODUCT HAVING A SOFTENING POINT (B. & R.) WITHIN THE RANGE OF APPROXIMATELY 70 TO 100*C. A SPECIFIC GRAVITY AT 25* C. OF .970 TO .975, A REFRACTIVE INDEX AT 20*C. OF 1.5116, AN ACID NUMBER LESS THAN ONE, AN IODINE VALUE (WIJS) OF 120, A BROMINE NUMBER OF 7.3 AND A MOLECULAR WEIGHT OF APPROXIMATELY 1100.
References Cited (Backward Citations)
US2894925A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-10-11 | 1964-04-11 | 1964-10-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-10-11 | 1968-04-11 | 1968-10-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-10-11 | 1972-04-11 | 1972-10-11 | $7700.00 | Window Closed / Lapsed |