US4407846A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing a hydrophilic membrane from a polyethylene base film
Assignee: Japan Atomic Energy Agency
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Filing: 1981-10-13
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Granted: 1983-10-04
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Expires: 2001-10-13
Abstract
Abstract A method of producing a hydrophilic membrane from a polyethylene base film by first irradiating the film with ionizing radiation in air or an oxygen atmosphere and then grafting acrylic acid and/or methacrylic acid onto the irradiated film at low temperatures.
Inventors
- 👤 Sueo Machi
- 👤 Isao Ishigaki
- 👤 Takanobu Sugo
- 👤 Kazuo Murata
- 👤 Shiro Tanso
- 👤 Keizi Senoo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:40
CPC Classifications
B; B01; B01D; B01D67/00; B01D67/0081; B01D67/0093; C; C08; C08J; C08J7/00; C08J7/12; C08J7/16; C08J7/18; B01D2323/00; B01D2323/38; B01D2323/385; C08J2323/00; C08J2323/02; C08J2323/04; C08J2323/06
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
88 words
A method of producing a hydrophylic membrane from a polyethylene base film by first irradiating the film of thickness not more than 150 μm with ionizing radiation in air or an oxygen atmosphere to give a total dose of 2 to 30 Mrad at a dose rate of 5×10 4 to 10 7 rad/sec, and then grafting without additional radiation acrylic acid and/or methacrylic acid present in the form of a 10-60 wt% aqueous solution onto the irradiated film at a temperature of 10° C. to 60° C.
Claim 2
Independent Claim
88 words
A method of producing a hydrophylic membrane from a polyethylene base film by first irradiating the film of thickness not more than 150 μm with ionizing radiation in air or an oxygen atmosphere to give a total dose of 2 to 30 Mrad at a dose rate of 5×10 4 to 10 7 rad/sec, and then grafting without additional radiation acrylic acid and/or methacrylic acid present in the form of a 10-60 wt% aqueous solution onto the irradiated film at a temperature of 10° C. to 60° C.
Claim 3
Dependent Claim
27 words
A method according to claim 1 wherein the aqueous solution of acrylic acid and/or methacrylic acid has the oxygen content thereof reduced to less than 0.1 ppm.
Claim 4
Dependent Claim
15 words
A method according to claim 1 wherein the degree of graft is at least 95%.
Claim 5
Dependent Claim
16 words
A method according to claim 1, wherein said temperature is no more than about 25° C.
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) | 1986-10-03 | 1987-04-04 | 1987-10-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-10-03 | 1991-04-04 | 1991-10-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-10-03 | 1995-04-04 | 1995-10-04 | $7700.00 | Window Closed / Lapsed |