Patent US4142404A successfully refreshed from Google Patents.
US4142404A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for pressure measurement
Assignee: Fujifilm Holdings Corp
•
Filing: 1976-10-05
•
Granted: 1979-03-06
•
Expires: 1996-10-05
Abstract
Abstract A method for measuring pressures which comprises allowing a material whose pressure is to be measured to press against a recording sheet to form a color image due to the pressure, and evaluating the changes in the optical color density of the color hue of the resulting color image on the recording sheet, the color image formation due to the pressure being effected by contacting a synthetic polymer microcapsule layer containing a color former with a color developer layer under pressure, said microcapsule layer and said color developer layer being coated on the same surface of the support.
Inventors
- 👤 Yasuhiro Ogata
- 👤 Kenji Ariyasu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 22:23
CPC Classifications
G; G01; G01L; G01L1/00; G01L1/24; G01L1/247; B; B01; B01J; B01J13/00; B01J13/02
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
107 words
In a method for measuring pressures which comprises pressing a material for which a pressure measurement is desired against a recording sheet to form a color image due to the pressure and evaluating the changes in the optical color density or the color hue of the resulting color image on the recording sheet, the improvement which comprises said color image formation due to the pressure being effected by contacting a substantially colorless color former contained in synthetic polymer microcapsules with a color developer under pressure, and said microcapsules and said color developer being coated on a same side of a support thereby to form said recording sheet.
Claim 2
Dependent Claim
107 words
In a method for measuring pressures which comprises pressing a material for which a pressure measurement is desired against a recording sheet to form a color image due to the pressure and evaluating the changes in the optical color density or the color hue of the resulting color image on the recording sheet, the improvement which comprises said color image formation due to the pressure being effected by contacting a substantially colorless color former contained in synthetic polymer microcapsules with a color developer under pressure, and said microcapsules and said color developer being coated on a same side of a support thereby to form said recording sheet.
Claim 3
Dependent Claim
22 words
The method for measuring pressures of claim 1, wherein changes in optical color density with respect to the pressures are directly proportional.
Claim 4
Dependent Claim
13 words
The method for measuring pressures of claim 2, wherein said proportionality is linear.
Claim 5
Dependent Claim
29 words
The method for measuring pressures of claim 1, wherein said recording sheet is capable of being used to measure pressures ranging from about 100 to 800 Kg/cm 2 .
Claim 6
Dependent Claim
27 words
The method for measuring pressures of claim 1, wherein said color former is a substantially colorless electron-donating organic compound and said color developer is an electron-accepting material.
Claim 7
Dependent Claim
58 words
The method for measuring pressures of claim 5, wherein said color former is a triarylmethane compound, a diarylmethane compound, a xathene compound, a thiaszine compound, a spiropyran compound or a mixture thereof and said color developer is a clay, an aromatic carboxylic acid, a metal salt of an aromatic hydroxy compound, an acidic polymer, or a mixture thereof.
Claim 8
Dependent Claim
63 words
The method for measuring pressures of claim 1, wherein said evaluation of the changes in the optical color density or the color hue of the resulting color image comprises reading the optical color density or the color hue and comparing said reading with a calibration of the optical density or the color hue changes of said recording sheet obtained with varying known pressures.
Claim 9
Dependent Claim
16 words
The method of claim 1 wherein said synthetic polymer is formed by reacting polyisocyanate with polyol.
Claim 10
Dependent Claim
33 words
The method of claim 1 wherein said synthetic polymer is a product selected from the group consisting of the product formed on reacting polyisocyanate with polyamine, polyisocyanate with polyol and polyisocyanate with water.
Claim 11
Dependent Claim
23 words
The method of claim 9, wherein said microcapsules and said developer are coated as distinct layers on the same side of the support.
Claim 12
Dependent Claim
13 words
The method of claim 9, wherein said color developer is a solid acid.
Claim 13
Dependent Claim
23 words
The method of claim 1, wherein said microcapsules and said developer are coated as distinct layers on the same side of the support.
Claim 14
Dependent Claim
18 words
The method of claim 1, wherein both said microcapsules and said developer are coated as a single layer.
Claim 15
Dependent Claim
19 words
The method of claim 13, wherein the ratio of said microcapsules to said developer is from 1:10 to 10:1.
Claim 16
Dependent Claim
13 words
The method of claim 1, wherein said color developer is a solid acid.
References Cited (Backward Citations)
US2730457A
Cited
US3469439A
Cited
US3647504A
Cited
US3922463A
Cited
US4012554A
Cited
US4012538A
Cited
US3955026A
Cited
US4002060A
Cited
US4085949A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-03-05 | 1982-09-04 | 1983-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-03-05 | 1986-09-04 | 1987-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-03-05 | 1990-09-04 | 1991-03-06 | $7700.00 | Window Closed / Lapsed |