US3857778A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of rendering electrophoresis membrane transparent
Assignee: Fujifilm Holdings Corp
•
Filing: 1971-11-03
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Granted: 1974-12-31
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Expires: 1991-11-03
Abstract
Abstract The present invention renders an electrophoretic membrane having a molecular weight range from 10,000 to 150,000 transparent by first impregnating the membrane with a lower alkyl alcohol and thereafter treating the membrane with an ether until the membrane becomes transparent. The temperature of the solvent liquids generally ranges from 10* to 35* C.
Inventors
- 👤 N Hiratsuka
- 👤 K Shimoda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 23:54
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/26; G01N27/416; G01N27/447; G01N27/44704; G01N27/44717; G01N27/44721
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
62 words
A METHOD OF RENDERING A CELLULOSE ESTER ELECTROPHORETIC MEMBRANE TRANSPARENT COMPRISING THE STEPS OF: IMMERSING THE MEMBRANE IN AN ALCOHOL SOLUTION TO IMPREGNATE SAID MEMBRANE, WITHDRAWING THE IMPREGNATED MEMBRANE FROM SAID ALCOHOL PLACING THE IMPREGNATED MEMBRANE ON A SUPPORT THEREBY EXCLUDING AIR FROM THE PORES OF SAID MEMBRANE, IMMERSING THE SUPPPORTED ALCOHOL-IMPREGNATED MEMBRANE IN AN ETHER AND, REMOVING AND DRYING THE MEMBRANE.
Claim 2
Independent Claim
62 words
A METHOD OF RENDERING A CELLULOSE ESTER ELECTROPHORETIC MEMBRANE TRANSPARENT COMPRISING THE STEPS OF: IMMERSING THE MEMBRANE IN AN ALCOHOL SOLUTION TO IMPREGNATE SAID MEMBRANE, WITHDRAWING THE IMPREGNATED MEMBRANE FROM SAID ALCOHOL PLACING THE IMPREGNATED MEMBRANE ON A SUPPORT THEREBY EXCLUDING AIR FROM THE PORES OF SAID MEMBRANE, IMMERSING THE SUPPPORTED ALCOHOL-IMPREGNATED MEMBRANE IN AN ETHER AND, REMOVING AND DRYING THE MEMBRANE.
Claim 3
Dependent Claim
15 words
A method as in claim 1, where the alcohol is a primary lower alkyl alcohol.
Claim 4
Dependent Claim
31 words
A method as in claim 2, wherein the ether is selected from the group consisting of dioxane, ethylene oxide, diethyl ether, methyl ethyl ether, diethyl dioxane and mixtures of said ethers.
Claim 5
Dependent Claim
27 words
A method as in claim 3, wherein the alcohol is selected from the group consisting of methyl alcohol, ethyl alcohol, butyl alcohol and mixtures of said alcohols.
Claim 6
Dependent Claim
20 words
A method as in claim 4, wherein the membrane is immersed in the alcohol for between 2 to 3 minutes.
Claim 7
Dependent Claim
21 words
A method as in claim 5, wherein the alcohol-impregnated membrane is immersed in the ether for between 3 to 5 minutes.
Claim 8
Dependent Claim
12 words
A method as in claim 5, wherein the membrane is cellulose triacetate.
Claim 9
Dependent Claim
22 words
A method as in claim 5, where the temperature range of the alcohol and ether is maintained between 10* and 35* C.
Claim 10
Dependent Claim
17 words
A method as in claim 5, where the membrane comprises cellulose triacetate, cellulose diacetate and glyceryl triacetate.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-12-30 | 1978-07-01 | 1978-12-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-30 | 1982-07-01 | 1982-12-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-30 | 1986-07-01 | 1986-12-31 | $7700.00 | Window Closed / Lapsed |