EP0183103A1
Expired / Lapsed
EP
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Flat permeable membrane and method for manufacture thereof
Assignee: Terumo Corp
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Filing: 1985-11-07
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Granted: —
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Expires: 2005-11-07
Abstract
Abstract A flat permeable polyolefin membrane 10 to 500 µm in thickness, which has in one surface thereof a compact layer formed of intimately bound fine polyolefin particles and possessed of fine pores and in the interior and the other surface thereof a layer formed of an aggregate of fine discrete polyolefin particles of an average diameter in the range of 0.01 to 5 µm so adjoined as to form fine labyrinthically continuing through pores and which, therefore, establishes communication between the opposite surfaces of said membrane.
Inventors
- 👤 Yukio Seita
- 👤 Makoto Emi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-23 04:04
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/28; B; B01; B01D; B01D67/00; B01D67/0002; B01D67/0023; B01D67/003; B01D69/00; B01D69/02; B01D69/06; B01D71/00; B01D71/06; B01D71/26; B01D71/262; B01D2323/00; B01D2323/08; B01D2323/081; B01D2323/082; B01D2323/12; C08J2201/00; C08J2201/02; C08J2201/03; C08J2201/04; C08J2201/054; C08J2201/0542; C08J2201/0543; C08J2201/0545; C08J2201/0546; C08J2323/00; C08J2323/02; Y; Y10; Y10T; Y10T428/00; Y10T428/31504; Y10T428/31855; Y10T428/31909; Y10T428/31913; Y10T428/31938
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
86 words
A flat permeable polyolefin membrane 10 to 500 µm in thickness, which has in one surface thereof a compact layer formed of intimately bound fine polyolefin particles and possessed of fine pores and in the interior and the other surface thereof a layer formed of an aggregate of fine discrete polyolefin particles of an average diameter in the range of 0.01 to 5 µm so adjoined as to form fine labyrinthically continuing through pores and which, therefore, establishes communication between the opposite surfaces of said membrane.
Claim 2
Dependent Claim
86 words
A flat permeable polyolefin membrane 10 to 500 µm in thickness, which has in one surface thereof a compact layer formed of intimately bound fine polyolefin particles and possessed of fine pores and in the interior and the other surface thereof a layer formed of an aggregate of fine discrete polyolefin particles of an average diameter in the range of 0.01 to 5 µm so adjoined as to form fine labyrinthically continuing through pores and which, therefore, establishes communication between the opposite surfaces of said membrane.
Claim 3
Dependent Claim
26 words
A flat permeable polyolefin membrane according to Claim 1, wherein said compact layer accounts for not more than 30% of the total thickness of said membrane.
Claim 4
Dependent Claim
23 words
A flat permeable polyolefin membrane according to Claim 1, wherein said polyolefin membrane has a porosity in the range of 10 to 85%.
Claim 5
Dependent Claim
20 words
A flat permeable polyolefin membrane according to Claim 3, wherein said porosity is in the range of 10 to 60%.
Claim 6
Dependent Claim
29 words
A flat permeable polyolefin membrane according to Claim 1, wherein said fine pores of said compact layer have an average diameter in the range of 0.01 to 5 µm.
Claim 7
Dependent Claim
36 words
A flat permeable polyolefin membrane according to Claim 1, wherein said fine particles of said layer formed of said aggregate of fine discrete particles have an average diameter in the range of 0.02 to 1.0 µm
Claim 8
Dependent Claim
28 words
A flat permeable polyolefin membrane according to Claim 1, wherein said polyolefin is at least one member selected from the group consisting of polyethylene, polypropylene, and ethylene-propylene copolymer.
Claim 9
Dependent Claim
20 words
A flat permeable polyolefin membrane according to Claim 1, wehrein said surface constituting said compact layer is flat and smooth.
Claim 10
Dependent Claim
41 words
A flat permeable polyolefin membrane according to Claim 1, wherein said polyolefin membrane has a porosity in the range of 10 to 85% and said shrinkage after a heat treatment performed at 121°C for 120 minutes is not more than 6.0%.
Claim 11
Dependent Claim
20 words
A flat permeable polyolefin membrane according to Claim 9, wherein said porosity is in the rang of 10 to 60%.
Claim 12
Dependent Claim
18 words
A flat permeable polyolefin membrane according to Claim 9, which is used for the separation of blood components.
Claim 13
Dependent Claim
24 words
A flat permeable polyolefin membrane according to Claim 10, wherein said thickness of the membrane is in the range of 20 to 300 um.
Claim 14
Dependent Claim
20 words
A flat permeable polyolefin membrane according to Claim 12, wherein said porosity is in the range of 30 to 80%.
Claim 15
Dependent Claim
26 words
A flat permeable polyolefin membrane according to Claim 11, wherein said average diameter of said fine pores is in the range of 0.02 to 2.0 um.
Claim 16
Dependent Claim
17 words
A flat permeable polyolefin membrane according to Claim 9, wherein said shrinkage is not more than 3.0%.
Claim 17
Independent Claim
102 words
A method for the manufacture of a flat permeable membrane, which is characterized by the steps of mixing a polyolefin, an organic filler uniformly dispersable in said polyolefin in the molten state thereof, and a crystal seed forming agent, discharging the resultant mixture in the molten state thereof through a die, bringing one surface of the discharged molten membrane into contact with a cooling roll thereby cooling and solidifying said membrane, and placing the cooled and solidified flat membrane into contact with an extractant incapable of dissolving said polyolefin thereby extracting and removing said organic filler from the web of said membrane.
Claim 18
Independent Claim
102 words
A method for the manufacture of a flat permeable membrane, which is characterized by the steps of mixing a polyolefin, an organic filler uniformly dispersable in said polyolefin in the molten state thereof, and a crystal seed forming agent, discharging the resultant mixture in the molten state thereof through a die, bringing one surface of the discharged molten membrane into contact with a cooling roll thereby cooling and solidifying said membrane, and placing the cooled and solidified flat membrane into contact with an extractant incapable of dissolving said polyolefin thereby extracting and removing said organic filler from the web of said membrane.
Claim 19
Dependent Claim
24 words
A method accroding to Claim 16, wherein said organic filler is a hydrocarbon having a boiling point exceeding the melting point of said polyolefin.
Claim 20
Dependent Claim
16 words
A method accroding to Claim 17, wherein said hydrocarbon is fluid paraffin or an a-olefin oligomer.
Claim 21
Dependent Claim
34 words
A method accroding to Claim 16, wherein said organic filler is incorporated in an amount in the range of 35 to 600 parts by weight based on 100 parts by weight of said polyolefin.
Claim 22
Dependent Claim
25 words
A method accroding to Claim 16, wherein said polyolefin is at least one member selected from the group consisting of polyethylene, polypropylene, and ethylene-propylene copolymer.
Claim 23
Dependent Claim
40 words
A method accroding to Claim 16, wherein said crystal seed forming agent is an organic heat-resisting substance having a melting point of not less than 150°C and a gel point exceeding the temperature at which said polyolefin begins to crystallize.
Claim 24
Dependent Claim
36 words
A method accroding to Claim 16, wherein said crystal seed forming agent is incorporated in an amount in the range of 0.1 to 5 parts by weight based on 100 parts by weight of said polyolefin.
Claim 25
Dependent Claim
24 words
A method accroding to Claim 16, wherein said extractant is at least one member selected from the group consising of alcohols and halogenaged hydrocarbons.
Claim 26
Dependent Claim
21 words
A method accroding to Claim 16, wherein said temperature of said cooling roll is in the range of 10° to 100°C.
Claim 27
Dependent Claim
55 words
A method for the manufacture of a flat permeable membrane according to Claim 16, further comprising steps of cooling and solidifying said membrane maintaining said flat membrane in a certain area, and subjecting said formed polyolefin membrane to a heat treatment at a temperature 20° to 50°C lower than the melting point of said polyolefin.
References Cited (Backward Citations)
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