US5032281A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Separating membrane and separation method
Assignee: Daicel Corp
•
Filing: 1990-07-20
•
Granted: 1991-07-16
•
Expires: 2010-07-20
Abstract
Abstract A separating membrane having a porous membrane structure with a pore size distribution such that the membrane does not permeate 90 percent or more of particles having a size of 0.5 micron when the membrane is 0.1 mm thick. The membrane is composed of a material having a nitrogen-containing compound and is liquid-permeable to adsorb and retain phosphopolyols contained in a liquid.
Inventors
- 👤 Shinji Nagamatsu
- 👤 Yoshikazu Tanaka
- 👤 Tohru Shibata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 05:31
CPC Classifications
A; A61; A61M; A61M1/00; A61M1/14; A61M1/16; A61M1/1654; A61M1/1656; A61M1/34; A61M1/342; A61M1/3455; B; B01; B01D; B01D39/00; B01D39/14; B01D39/16; B01D61/00; B01D61/24; B01D67/00; B01D67/0081; B01D67/0093; B01D67/00931; B01D69/00; B01D69/02; B01D71/00; B01D71/06; B01D71/58; C; C12; C12Q; C12Q1/00; C12Q1/68; G; G01; G01N; G01N33/00; G01N33/48; G01N33/50; G01N33/53; G01N33/543; G01N33/544; B01D2325/00; B01D2325/02; B01D2325/0283
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
106 words
A separating membrane for separating drugs from pyrogens having similar molecular weights, selectively absorbing a pyrogen and treating large quantities of liquid at a high speed while effectively lowering the pyrogen content thereof, said membrane comprising a nitrogen-containing compound and having a porous membrane structure with a pore size distribution such that at least 90% of particles having a size of 0.5 microns or larger are blocked by said membrane when it has a thickness of 0.1 mm or more, said membrane being liquid permeable so as to be able to absorb and remove phosphopolyols contained in a liquid while permitting the liquid to pass therethrough.
Claim 2
Dependent Claim
106 words
A separating membrane for separating drugs from pyrogens having similar molecular weights, selectively absorbing a pyrogen and treating large quantities of liquid at a high speed while effectively lowering the pyrogen content thereof, said membrane comprising a nitrogen-containing compound and having a porous membrane structure with a pore size distribution such that at least 90% of particles having a size of 0.5 microns or larger are blocked by said membrane when it has a thickness of 0.1 mm or more, said membrane being liquid permeable so as to be able to absorb and remove phosphopolyols contained in a liquid while permitting the liquid to pass therethrough.
Claim 3
Dependent Claim
16 words
The membrane as claimed in claim 1, in which the compound is a nitrogen-containing cyclic compound.
Claim 4
Dependent Claim
26 words
The membrane as claimed in claim 1, in which the compound is a nitrogen-containing compound having an aliphatic chain group of 3 to 50 carbon atoms.
Claim 5
Dependent Claim
21 words
The membrane as claimed in claim 1, in which the compound is a nitrogen-containing cyclic compound with a pai electron system.
Claim 6
Dependent Claim
124 words
In a method for separating phosphopolyols from a liquid containing them, the improvement comprising passing said liquid through a separating membrane for separating drugs from pyrogens having similar molecular weights, selectively absorbing a pyrogen and treating large quantities of liquid at a high speed while effectively lowering the pyrogen content thereof, said membrane comprising a nitrogen-containing compound and having a porous membrane structure with a pore size distribution such that at least 90% of particles having a size of 0.5 microns or larger are blocked by said membrane when it has a thickness of 0.1 mm or more, said membrane being liquid permeable so as to be able to absorb and remove phosphopolyols contained in a liquid while permitting the liquid to pass therethrough.
Claim 7
Dependent Claim
124 words
In a method for separating phosphopolyols from a liquid containing them, the improvement comprising passing said liquid through a separating membrane for separating drugs from pyrogens having similar molecular weights, selectively absorbing a pyrogen and treating large quantities of liquid at a high speed while effectively lowering the pyrogen content thereof, said membrane comprising a nitrogen-containing compound and having a porous membrane structure with a pore size distribution such that at least 90% of particles having a size of 0.5 microns or larger are blocked by said membrane when it has a thickness of 0.1 mm or more, said membrane being liquid permeable so as to be able to absorb and remove phosphopolyols contained in a liquid while permitting the liquid to pass therethrough.
Claim 8
Dependent Claim
13 words
The method as claimed in claim 5, in which the phosphopolyols are pyrogens.
Claim 9
Dependent Claim
20 words
The method as claimed in claim 5, in which the compound is a nitrogen-containing compound having a pai electron system.
Claim 10
Dependent Claim
26 words
The method as claimed in claim 5, in which the compound is a nitrogen-containing compound having an aliphatic chain group of 3 to 50 carbon atoms.
References Cited (Backward Citations)
US4261834A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-07-15 | 1995-01-14 | 1995-07-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-07-15 | 1999-01-14 | 1999-07-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-07-15 | 2003-01-14 | 2003-07-16 | $7700.00 | Window Closed / Lapsed |