US4960464A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Erasable ink composition
Assignee: Individual
•
Filing: 1989-08-31
•
Granted: 1990-10-02
•
Expires: 2009-08-31
Abstract
Abstract An ink which consists of 17-20% by weight of a graphite powder, 17-20% by weight of a lubricating oil having a low viscosity and a low melting point, 44-47% by weight of oleic acid extracted from vegetable oil, 15-17% by weight of ethylene glycol, and 450-500 ppm of ferrous sulfate, the oleic acid and the ethylene glycol reacting with one another and serving as a carrier, and the ferrous sulfate catalyzing the reaction between the oleic acid and the ethylene glycol.
Inventors
- 👤 Ching-Fei Chen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:59
CPC Classifications
C; C09; C09D; C09D11/00; C09D11/16
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
80 words
An ink consisting of 17-20% by weight of a graphite powder, 17-20% by weight of a lubricating oil having a low viscosity and a low melting point, 44-47% by weight of oleic acid extracted from vegetable oil, 15-17% by weight of ethylene glycol, and 450-500 ppm of ferrous sulfate, the oleic acid and the ethylene glycol reacting with one another and serving as a carrier, and the ferrous sulfate catalyzing the reaction between the oleic acid and the ethylene glycol.
Claim 2
Dependent Claim
80 words
An ink consisting of 17-20% by weight of a graphite powder, 17-20% by weight of a lubricating oil having a low viscosity and a low melting point, 44-47% by weight of oleic acid extracted from vegetable oil, 15-17% by weight of ethylene glycol, and 450-500 ppm of ferrous sulfate, the oleic acid and the ethylene glycol reacting with one another and serving as a carrier, and the ferrous sulfate catalyzing the reaction between the oleic acid and the ethylene glycol.
References Cited (Backward Citations)
US2239142A
Cited
US2852397A
Cited
US2715388A
Cited
US4209332A
Cited
US4371632A
Cited
US4687791A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-10-01 | 1994-04-02 | 1994-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-10-01 | 1998-04-02 | 1998-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-10-01 | 2002-04-02 | 2002-10-02 | $7700.00 | Window Closed / Lapsed |