US4167725A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dew-sensing hygroscopic element
Assignee: Sony Corp
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Filing: 1977-08-04
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Granted: 1979-09-11
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Expires: 1997-08-04
Abstract
Abstract A dew-sensing hygroscopic element includes a pair of electrodes and a dew-sensing hygroscopic material arranged between the electrodes which detects dew by the change of impedance between the electrodes. The dew-sensing hygroscopic material comprises polyvinyl alcohol having a saponification equivalent of 20 to 65 as a base material and contains an organic electrolyte.
Inventors
- 👤 Hidetoshi Shimizu
- 👤 Hidemasa Tamura
- 👤 Yoshimi Makino
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 03:45
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/02; G01N27/04; G01N27/12; G01N27/121; C; C08; C08L; C08L29/00; C08L29/02; C08L29/04
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
82 words
In a dew-sensing hygroscopic element including a pair of electrodes and a dew-sensing hygroscopic material arranged between said electrodes for detecting dew with the change of impedance between said electrodes, the improvement comprising wherein said dew-sensing hygroscopic material comprises polyvinyl alcohol having a saponification equivalent raging from 20 to 65 as a base material and containing therein an amount of an organic electrolyte in the range of 6×10 -4 to 0.14 gram equivalent based on 100 grams of said dew-sensing hygroscopic material.
Claim 2
Dependent Claim
82 words
In a dew-sensing hygroscopic element including a pair of electrodes and a dew-sensing hygroscopic material arranged between said electrodes for detecting dew with the change of impedance between said electrodes, the improvement comprising wherein said dew-sensing hygroscopic material comprises polyvinyl alcohol having a saponification equivalent raging from 20 to 65 as a base material and containing therein an amount of an organic electrolyte in the range of 6×10 -4 to 0.14 gram equivalent based on 100 grams of said dew-sensing hygroscopic material.
Claim 3
Dependent Claim
27 words
In a dew-sensing hygroscopic element as defined in claim 1, wherein said organic electrolyte is a metallic salt of a C 1 to C 20 organic acid.
Claim 4
Dependent Claim
23 words
In a dew-sensing hygroscopic element as defined in claim 2 wherein said organic acid is C 1 to C 5 of fatty acid.
Claim 5
Dependent Claim
24 words
In a dew-sensing hygroscopic element as defined in claim 2, wherein a cation of said metallic salt of organic acid is an alkali metal.
Claim 6
Dependent Claim
26 words
In a dew-sensing hygroscopic element as defined in claim 1, wherein said polyvinyl alcohol has a mean polymerization degree in the range of 200 to 3000.
Claim 7
Dependent Claim
27 words
In a dew-sensing hygroscopic element as defined in claim 1, wherein said dew-sensing hygroscopic material is in the form of film having a thickness less than 10μ.
Claim 8
Dependent Claim
24 words
In a dew-sensing hygroscopic element as defined in claim 6 wherein said film has a thickness in the range of about 2 to 9μ.
References Cited (Backward Citations)
US2937524A
Cited
US3295088A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-09-10 | 1983-03-12 | 1983-09-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-09-10 | 1987-03-12 | 1987-09-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-09-10 | 1991-03-12 | 1991-09-11 | $7700.00 | Window Closed / Lapsed |