US3753761A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pressure sensitive recording paper
Assignee: Mizusawa Industrial Chemicals Ltd
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Filing: 1971-08-31
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Granted: 1973-08-21
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Expires: 1991-08-31
Abstract
Abstract A pressure sensitive recording paper comprising a paper substrate and a coating thereon comprising a color former which comprises a member selected from the group consisting of acidtreated dioctahedral montmorillonite clay minerals and mixtures of such minerals with natural dioctahedral montmorillonite clay minerals, the minerals having a secondary color development property, K2, of at least 1.40, the value of K2 being represented by the formula
Inventors
- 👤 T Nakazawa
- 👤 M Maeno
- 👤 Y Sugahara
- 👤 K Miyazawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:43
CPC Classifications
C; C01; C01B; C01B33/00; C01B33/20; C01B33/36; C01B33/38; C01B33/42; B; B41; B41M; B41M5/00; B41M5/124; B41M5/132; B41M5/155; B41M5/1555; C01B33/26; C01B33/40; C01B33/46; Y; Y10; Y10T; Y10T428/00; Y10T428/25; Y10T428/259
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
24 words
The pressure sensitive recording paper of claim 1 wherein said minerals have a specific surface area within the range of 180 - 350 m2/g.
Claim 2
Dependent Claim
17 words
The pressure sensitive recording paper of claim 1 wherein the value of K2 is at least 1.60.
Claim 3
Dependent Claim
53 words
The pressure sensitive recording paper of claim 1 wherein of the total particles of said color former at least 85 percent by weight of said particles have a diameter of 10 microns or less and not more than 35 percent by weight of said particles have a diameter of 1 micron or less.
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) | 1976-08-20 | 1977-02-19 | 1977-08-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-20 | 1981-02-19 | 1981-08-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-20 | 1985-02-19 | 1985-08-21 | $7700.00 | Window Closed / Lapsed |