Patent US4239608A successfully refreshed from Google Patents.
US4239608A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for producing piezoelectric polymeric material
Assignee: Post Office
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Filing: 1978-07-19
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Granted: 1980-12-16
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Expires: 1998-07-19
Abstract
Abstract A method of enhancing the piezoelectric properties of a polymeric material exhibiting such properties includes the step of exposing the material to a quantity of gamma radiation lying within the range of from 1 Mrad to 200 Mrads. The material is subsequently poled. Best results are obtained when the material is exposed to between 1 Mrad and 100 Mrads of radiation. The material treated may be polyvinylidene fluoride.
Inventors
- 👤 Philippos Pantelis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 08:41
CPC Classifications
H; H10; H10N; H10N30/00; H10N30/01; H10N30/09; H10N30/098; Y; Y10; Y10S; Y10S522/00; Y10S522/911; Y10S522/912
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
93 words
A method of enhancing the piezoelectric voltage coefficient of a polymeric material exhibiting piezoelectric properties, the method including the step of exposing the material whilst in an atmosphere inert with respect to the material and at substantially room temperature to a quantity of γ radiation lying within the range of from 1 Mrad to 200 Mrads (both limits included) after which the material is subjected to a poling treatment whereby the piezoelectric voltage coefficient of the material is increased over that obtained by subjecting the material without prior irradiation to said poling treatment.
Claim 2
Independent Claim
93 words
A method of enhancing the piezoelectric voltage coefficient of a polymeric material exhibiting piezoelectric properties, the method including the step of exposing the material whilst in an atmosphere inert with respect to the material and at substantially room temperature to a quantity of γ radiation lying within the range of from 1 Mrad to 200 Mrads (both limits included) after which the material is subjected to a poling treatment whereby the piezoelectric voltage coefficient of the material is increased over that obtained by subjecting the material without prior irradiation to said poling treatment.
Claim 3
Dependent Claim
31 words
A method according to claim 1, wherein the quantity of radiation to which the material is exposed lies in the range of from 1 Mrad to 99 Mrads (both limits included).
Claim 4
Dependent Claim
25 words
A method according to claim 1, wherein the inert atmosphere is a vacuum in which the air pressure does not exceed 10 -3 mm Hg.
Claim 5
Independent Claim
81 words
A method of enhancing the piezoelectric voltage coefficient of polyvinylidene fluoride by exposing the polyvinylidene fluoride whilst in an atmosphere inert thereto and at substantially room temperature to a quantity of γ radiation lying within the range of from 1 Mrad to 200 Mrads (both limits included) after which the material is subjected to a poling treatment whereby the piezoelectric voltage coefficient of the material is increased over that obtained by subjecting the material without prior irradiation to said poling treatment.
Claim 6
Independent Claim
81 words
A method of enhancing the piezoelectric voltage coefficient of polyvinylidene fluoride by exposing the polyvinylidene fluoride whilst in an atmosphere inert thereto and at substantially room temperature to a quantity of γ radiation lying within the range of from 1 Mrad to 200 Mrads (both limits included) after which the material is subjected to a poling treatment whereby the piezoelectric voltage coefficient of the material is increased over that obtained by subjecting the material without prior irradiation to said poling treatment.
Claim 7
Dependent Claim
19 words
A method according to claim 4 wherein the polyvinylidene fluoride is in the form of a biaxially orientated film.
Claim 8
Dependent Claim
31 words
A method according to claim 4, wherein the quantity of radiation to which the material is exposed lies in the range of from 1 Mrad to 99 Mrads (both limits included).
Claim 9
Dependent Claim
25 words
A method according to claim 4, wherein the inert atmosphere is a vacuum in which the air pressure does not exceed 10 -3 mm Hg.
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) | 1983-12-16 | 1984-06-16 | 1984-12-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-12-16 | 1988-06-16 | 1988-12-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-12-16 | 1992-06-16 | 1992-12-16 | $7700.00 | Window Closed / Lapsed |