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US4331622A Expired / Lapsed US ⏱️ 0.0 years remaining

Method for manufacturing a microporous film having low electrical resistance and high durability

Assignee: Asahi Kasei Corp
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Filing: 1980-01-14
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Granted: 1982-05-25
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Expires: 2000-01-14
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Abstract

Abstract A microporous film which comprises a matrix comprising 40 to 90 volume percent of a polyolefin having a number average molecular weight of 15,000 or more and 10 to 60 volume percent of an inorganic filler, said matrix having therein void spaces at a rate of 30 to 75 volume percent based on the volume of the film; and 2 to 20 weight percent, based on the total weight of the polyolefin and the inorganic filler, of an organic substance which is substantially insoluble in and inert to sulfuric acid and has a solubility parameter ranging from 7.3 inclusive to 8.4 exclusive; said organic substance, in its majority, adhering to the overall surface of the film including the outer surfaces of the film and the surfaces of the polyolefin walls defining said void spaces in cooperation with said inorganic filler.

Inventors

  • 👤 Yoshinao Doi
  • 👤 Osamu Fujii
  • 👤 Shigeo Kaneko
  • 👤 Takeo Hanamura

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 20:18
CPC Classifications
C; C08; C08J; C08J9/00; C08J9/28; B; B29; B29C; B29C67/00; B29C67/20; B29C67/202; H; H01; H01M; H01M50/00; H01M50/40; H01M50/409; H01M50/411; H01M50/414; H01M50/417; H01M50/489; H01M50/491; C08J2201/00; C08J2201/04; C08J2201/054; C08J2201/0542; C08J2201/0543; C08J2201/0545; C08J2201/0546; C08J2323/00; C08J2323/02; H01M2300/00; H01M2300/0002; H01M2300/0005; Y; Y02; Y02E; Y02E60/00; Y02E60/10

Claims Analysis

Total Claims: 34
Claim 1
Independent Claim 217 words
A method of manufacturing a microporous film which comprises: blending a polyolefin having a number average molecular weight of 15,000 or more, an inorganic filler, and an organic liquid (A) having a solubility parameter ranging from 8.4 to 9.9 inclusive in amounts of 10 to 60 volume percent, 7 to 42 volume percent, and 30 to 75 volume percent, respectively, based on the whole volume of the polyolefin-filler-organic liquid (A) composition, the amount of the polyolefin being 2/3 to 9 multiple of the amount of the inorganic filler; subjecting the resulting blend to molding to form a film; extracting from said film the organic liquid (A) to form a matrix which comprises 40 to 90 volume percent of the polyolefin and 10 to 60 volume percent of the inorganic filler and having therein void spaces at a rate of 30 to 75 volume percent based on the volume of the film; and applying to the matrix an organic substance (B) which is substantially insoluble in and inert to sulfuric acid and has a solubility parameter ranging from 7.3 inclusive to 8.4 exclusive so that said organic substance (B) adheres to the overall surface of the film in an amount of 2 to 20 weight percent based on the total weight of the polyolefin and the inorganic filler.
Claim 2
Independent Claim 217 words
A method of manufacturing a microporous film which comprises: blending a polyolefin having a number average molecular weight of 15,000 or more, an inorganic filler, and an organic liquid (A) having a solubility parameter ranging from 8.4 to 9.9 inclusive in amounts of 10 to 60 volume percent, 7 to 42 volume percent, and 30 to 75 volume percent, respectively, based on the whole volume of the polyolefin-filler-organic liquid (A) composition, the amount of the polyolefin being 2/3 to 9 multiple of the amount of the inorganic filler; subjecting the resulting blend to molding to form a film; extracting from said film the organic liquid (A) to form a matrix which comprises 40 to 90 volume percent of the polyolefin and 10 to 60 volume percent of the inorganic filler and having therein void spaces at a rate of 30 to 75 volume percent based on the volume of the film; and applying to the matrix an organic substance (B) which is substantially insoluble in and inert to sulfuric acid and has a solubility parameter ranging from 7.3 inclusive to 8.4 exclusive so that said organic substance (B) adheres to the overall surface of the film in an amount of 2 to 20 weight percent based on the total weight of the polyolefin and the inorganic filler.
Claim 3
Dependent Claim 27 words
A method as set forth in claim 1, wherein said solubility parameter of the organic substance (B) is in the range of from 7.5 to 8.3 inclusive.
Claim 4
Dependent Claim 21 words
A method as set forth in claim 1, wherein said polyolefin has a weight average molecular weight of less than 600,000.
Claim 5
Dependent Claim 21 words
A method as set forth in claim 1, wherein said polyolefin has a weight average molecular weight of less than 300,000.
Claim 6
Dependent Claim 19 words
A method as set forth in claim 4, wherein said weight average molecular weight ranges from 85,000 to 250,000.
Claim 7
Dependent Claim 21 words
A method as set forth in claim 1, wherein said polyolefin has a number average molecular weight of 17,000 to 50,000.
Claim 8
Dependent Claim 21 words
A method as set forth in claim 1, wherein said polyolefin has a standard load melt index of 0.01 or more.
Claim 9
Dependent Claim 22 words
A method as set forth in claim 7, wherein said standard load melt index is in the range of 0.03 to 1.
Claim 10
Dependent Claim 15 words
A method as set forth in claim 1, wherein said polyolefin is an olefin homopolymer.
Claim 11
Dependent Claim 15 words
A method as set forth in claim 1, wherein said polyolefin is an olefin copolymer.
Claim 12
Dependent Claim 13 words
A method as set forth in claim 1, wherein said polyolefin is polyethylene.
Claim 13
Dependent Claim 15 words
A method as set forth in claim 10, wherein said polyolefin is an ethylene copolymer.
Claim 14
Dependent Claim 23 words
A method as set forth in claim 12, wherein said ethylene copolymer is an ethylene-propylene copolymer, an ethylene-butene copolymer or an ethylene-propylene-butene terpolymer.
Claim 15
Dependent Claim 23 words
A method as set forth in claim 12, wherein said polyolefin is a copolymer of ethylene as a main component with other olefin.
Claim 16
Dependent Claim 16 words
A method as set forth in claim 1, wherein said inorganic filler is finely divided silica.
Claim 17
Dependent Claim 34 words
A method as set forth in claim 1, wherein the amount of said organic substance (B) is 3 to 15 weight percent based on the total weight of the polyolefin and the inorganic filler.
Claim 18
Dependent Claim 46 words
A method as set forth in claim 1, wherein said organic substance (B) is a member selected from the group consisting of petroleum hydrocarbons, coal tar hydrocarbons, low molecular weight polyolefins, fatty oils, silicone oils, polymer of β-pinene, hydrogenated rosin oil, tris(nonylphenyl) phosphite, and mixtures thereof.
Claim 19
Dependent Claim 52 words
A method as set forth in claim 17, wherein the petroleum hydrocarbon is a member selected from the group consisting of a naphthenic process oil, an aromatic process oil, a paraffinic process oil, a lubricating oil, a liquid paraffin, a petroleum, an ozokelite, a petroleum asphalt, a petroleum resin, and mixtures thereof.
Claim 20
Dependent Claim 32 words
A method as set forth in claim 17, wherein the coal tar hydrocarbon is a member selected from the group consisting of coumaron-indene resin, coal tar, coal tar pitch, and mixtures thereof.
Claim 21
Dependent Claim 36 words
A method as set forth in claim 17, wherein the low molecular weight polyolefin is a member selected from the group consisting of a polyethylene wax, a polyisobutylene, a polybutadiene, an atactic polypropylene, and mixtures thereof.
Claim 22
Dependent Claim 40 words
A method as set forth in claim 17, wherein the fatty oil is a member selected from the group consisting of soya bean oil, castor oil, cotton seed oil, linseed oil, rapeseed oil, palm oil, coconut oil, and mixtures thereof.
Claim 23
Dependent Claim 28 words
A method as set forth in claim 17, wherein the silicone oil as a member selected from the group consisting of polydimethyl siloxane, polymethylphenyl siloxane, and mixtures thereof.
Claim 24
Dependent Claim 36 words
A method as set forth in claim 18, wherein said petroleum hydrocarbon is a member selected from the group consisting of a naphthenic process oil, an aromatic process oil, a paraffin process oil, and mixtures thereof.
Claim 25
Dependent Claim 34 words
A method as set forth in claim 18 wherein said petroleum hydrocarbon is a lubricating oil selected from the group consisting of a spindle oil, a machine oil, a cylinder oil and mixtures thereof.
Claim 26
Dependent Claim 27 words
A method as set forth in claim 1, wherein the application of said organic substance (B) to the matrix is carried out by dipping, spraying or coating.
Claim 27
Dependent Claim 32 words
A method as set forth in claim 1, wherein said organic substance (B) is applied to the matrix in the form of the organic substance (B) as it is or its solution.
Claim 28
Dependent Claim 35 words
A method as set forth in claim 25, wherein said dipping is carried out using a 1.5 to 15% by weight solution of the organic substance (B) in a solvent for 10 seconds or more.
Claim 29
Dependent Claim 30 words
A method as set forth in claim 25, wherein said spraying is carried out using a 1.5 to 20% by weight solution of the organic substance (B) in a solvent.
Claim 30
Dependent Claim 37 words
A method as set forth in claim 25, wherein said coating is carried out by a knife coater or roll coater using a 1.5 to 20% by weight solution of the organic substance (B) in a solvent.
Claim 31
Independent Claim 38 words
A method as set forth in any of claims 27 to 29, wherein said solvent is a member selected from the group consisting of1,1,1-trichloroethane, trichloroethylene, methanol, ethanol, isopropyl alcohol, acetone, methyl ethyl ketone, petroleum ether, heptane, and hexane.
Claim 32
Dependent Claim 25 words
A method as set forth in claim 1, wherein said solubility parameter of the organic liquid (A) is in the range of 8.6 to 9.4.
Claim 33
Dependent Claim 19 words
A method as set forth in claim 1, wherein said organic liquid (A) is dioctyl phthalate or trioctyl trimellitate.
Claim 34
Dependent Claim 43 words
A method as set forth in claim 1, wherein said matrix further contains 5 or less volume percent based on the matrix of the organic liquid (A) having a solubility parameter ranging from 8.4 to 9.9 inclusive, said organic liquid (A) remaining unextracted.

References Cited (Backward Citations)

US3351495A Cited
US3853601A Cited
US3929509A Cited
DE2627229A1 Cited
US4190707A Cited
US4210709A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1985-05-24 1985-11-23 1986-05-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1989-05-24 1989-11-23 1990-05-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1993-05-24 1993-11-23 1994-05-25 $7700.00 Window Closed / Lapsed

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