Claims
- 1. A separator film for interposition between an anode and a cathode of a storage battery, comprising a porous oriented film consisting essentially of hydrophobic resin having pores therein, and one or more hydrophilic polymers fixed to said hydrophobic resin of said porous oriented film, a heterogeneous distribution of said hydrophilic polymer or polymers in or on said porous oriented film, said heterogeneous distribution forming in said porous oriented film a first film portion and a second film portion, said first film portion formed by said heterogeneous distribution having a first hydrophilicity caused by said hydrophilic polymer or polymers, said second film portion formed by said heterogeneous distribution containing a smaller amount of said hydrophilic polymer or polymers than said first film portion or no hydrophilic polymer, whereby said second film portion has a second hydrophilicity that is lower than said first hydrophilicity of said first film portion or a hydrophobicity caused by said hydrophobic resin, and wherein said porous oriented film has a gas permeability.
- 2. The separator film of claim 1, wherein said hydrophobic resin is fluororesin.
- 3. The separator film of claim 1, wherein said porous oriented film is a biaxially oriented film.
- 4. The separator film of claim 1, wherein said second film portion is provided in the form of spots or stripes in said porous oriented film.
- 5. The separator film of claim 1, wherein said second film portion is formed along one major surface of a pair of opposite major surfaces of said porous oriented film.
- 6. The separator film of claim 1, wherein said porous oriented film comprises a stack of superposed separate film plies including a first film ply having a hydrophilicity and a second film ply having one of a hydrophobicity and a hydrophilicity lower than that of said first film ply.
- 7. The separator film of claim 1, wherein said porous oriented film has a porosity of at least about 70%, a thickness in a range of about 10 to about 500 .mu.m, and a pore size in a range of about 0.01 to about 20 .mu.m.
- 8. The separator film of claim 1, wherein said hydrophilic polymer comprises one or more polymers selected from the group consisting of a polymer containing hydroxyl groups, a polymer containing carboxyl groups, a polymer containing imine, and a polymer containing sulfonic acid groups.
- 9. A separator film for interposition between an anode and a cathode of a storage battery, consisting essentially of a single porous oriented film consisting essentially of hydrophobic resin having pores therein, and one or more hydrophilic polymers fixed to said porous oriented film, wherein said pores of said porous oriented film comprises pore sizes that vary in the thickness direction of said porous oriented film, and wherein said porous oriented film has a gas permeability.
- 10. The separator film of claim 9, wherein said hydrophobic resin is fluororesin.
- 11. The separator film of claim 9, wherein said porous oriented film is a biaxially oriented film.
- 12. The separator film of claim 1, wherein a portion of said porous oriented film positioned next to at least one major surface of a pair of major surfaces of said porous oriented film comprises pores having a smaller pore size than pores in an interior portion of said porous oriented film.
- 13. The separator film of claim 12, wherein said pore size is gradually reduced from one major surface toward the other major surface.
- 14. The separator film of claim 12, wherein said interior portion comprises pores of larger pore size than the pore size in film portions along both major surfaces.
- 15. The separator film of claim 9, further comprising a heterogeneous distribution of said hydrophilic polymer or polymers in said porous oriented film, said heterogeneous distribution forming in said porous oriented film a first film portion having a first hydrophilicity caused by said hydrophilic polymer or polymers and a second film portion having one of a hydrophobicity and a second hydrophilicity that is lower than said first hydrophilicity of said first film portion.
- 16. The separator film of claim 9, wherein said porous oriented film has a porosity of at least about 70%, a thickness in a range of about 10 to 500 .mu.m, and a pore size in a range of about 0.01 to about 20 .mu.m.
- 17. The separator film of claim 9, wherein said hydrophilic polymer or polymers comprise one or more polymers selected from the group consisting of a polymer containing hydroxyl groups, a polymer containing carboxyl groups, a polymer containing imine, and a polymer containing sulfonic acid groups.
- 18. A separator film for interposition between an anode and a cathode of a storage battery, consisting essentially of a single porous resin film consisting essentially of hydrophilized hydrophobic resin and pores in said porous resin film, said porous resin film having porosities that vary in the thickness direction of said porous resin film, and wherein said porous resin film has a gas permeability.
- 19. The separator film of claim 18, wherein said hydrophobic resin is fluororesin and/or polyolefin resin.
- 20. The separator film of claim 18, wherein said hydrophobic resin is an oriented film.
- 21. The separator film of claim 20, wherein said hydrophobic resin is a biaxially oriented film.
- 22. The separator film of claim 18, wherein said porous resin film comprises a porous film consisting essentially of hydrophobic resin, and one or more hydrophilic polymers fixed to said porous resin film.
- 23. The separator film of claim 22, further comprising a heterogeneous distribution of said hydrophilic polymer in or on said porous resin film, said porous resin film further comprising a first film portion having a first hydrophilicity caused by said hydrophilic polymer or polymers and a second film portion having one of a hydrophobicity and a second hydrophilicity that is lower than said first hydrophilicity of said first film portion.
- 24. The separator film of claim 22, wherein said porous resin film has a porosity of at least about 70%, a thickness in a range of about 10 to about 500 .mu.m, and a pore size in a range of about 0.01 to about 20 .mu.m.
- 25. The separator film of claim 22, wherein said hydrophilic polymer or polymers comprises one or more polymers selected from the group consisting of a polymer containing hydroxyl groups, a polymer containing carboxyl groups, a polymer containing imine, and a polymer containing sulfonic acid groups.
- 26. The separator film of claim 18, wherein said porous resin film comprises a plurality of film plies having different porosities, said film plies forming a stack.
- 27. The separator film of claim 18, wherein said porous resin film comprises a porous, oriented fluororesin film hydrophilized by one or more hydrophilic polymers fixed to said porous oriented fluororesin film, and a hydrophilized porous polyolefin resin film superimposed on said porous oriented fluororesin film, and wherein each of said porous oriented fluororesin film and said polyolefin resin film has a different porosity.
Priority Claims (5)
Number |
Date |
Country |
Kind |
5-219443 |
Sep 1993 |
JPX |
|
5-257174 |
Oct 1993 |
JPX |
|
5-257175 |
Oct 1993 |
JPX |
|
5-257361 |
Oct 1993 |
JPX |
|
6-012635 |
Feb 1994 |
JPX |
|
Parent Case Info
This application is a continuation of U.S. application Ser. No.: 08/299,509; filed on.: Sep. 1, 1994, now abandoned.
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5094895 |
Branca et al. |
Mar 1992 |
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5100723 |
Iwasaki et al. |
Mar 1992 |
|
5591542 |
Sakamoto et al. |
Jan 1997 |
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51-18991 |
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Continuations (1)
|
Number |
Date |
Country |
Parent |
299509 |
Sep 1994 |
|