Laminated body

Patent metadata

Field	Value
Publication number	US-10461297-B2
Application number	US-201715627736-A
Country	US
Kind code	B2
Filing date	Jun 20, 2017
Priority date	Jun 21, 2016
Publication date	Oct 29, 2019
Grant date	Oct 29, 2019

Abstract

To afford a laminated body that is usable as a nonaqueous electrolyte secondary battery separator and that is not easily curled, a laminated body includes: a porous base material containing a polyolefin-based resin as a main component; and a porous layer containing a polyvinylidene fluoride-based resin, the porous base material having a parameter X of not more than 20, the parameter X being calculated in accordance with a particular formula, the polyvinylidene fluoride-based resin containing crystal form α in an amount of not less than 36 mol % with respect to 100 mol % of a total amount of the crystal form α and crystal form β contained in the polyvinylidene fluoride-based resin.

First claim

The invention claimed is:

1. A laminated body, comprising:
a porous base material containing a polyolefin-based resin as a main component; and
a porous layer on at least one surface of the porous base material, the porous layer containing a polyvinylidene fluoride-based resin,
the porous base material having a parameter X of not more than 20, the parameter X being calculated in accordance with a formula below, where MD tan δ represents a tan δ measured in a machine direction through a viscoelasticity measurement performed at a frequency of 10 Hz and a temperature of 90° C., and TD tan δ represents a tan δ measured in a transverse direction through the viscoelasticity measurement,
X= 100×|MD tan δ−TD tan δ|/{(MD tan δ+TD tan δ)/2}

the polyvinylidene fluoride-based resin containing crystal form α in an amount of not less than 36 mol % with respect to 100 mol % of a total amount of the crystal form α and crystal form β contained in the polyvinylidene fluoride-based resin,
where the amount of the crystal form α is calculated from an absorption intensity at around 765 cm −1 in an IR spectrum of the porous layer, and an amount of the crystal form β is calculated from an absorption intensity at around 840 cm −1 in the IR spectrum of the porous layer.

2. The laminated body according to claim 1 ,
wherein
the polyvinylidene fluoride-based resin contains (i) a homopolymer of vinylidene fluoride and/or (ii) a copolymer of vinylidene fluoride and at least one monomer selected from the group consisting of hexafluoropropylene, tetrafluoroethylene, trifluoroethylene, trichloroethylene, and vinyl fluoride.

3. The laminated body according to claim 1 ,
wherein
the polyvinylidene fluoride-based resin has a weight-average molecular weight of not less than 200,000 and not more than 3,000,000.

4. The laminated body according to claim 1 ,
wherein
the porous layer contains a filler.

5. The laminated body according to claim 4 ,
wherein
the filler has a volume-average particle size of not less than 0.01 μm and not more than 10 μm.

6. A nonaqueous electrolyte secondary battery member, comprising:
a cathode;
a laminated body according to claim 1 ; and
an anode,
the cathode, the laminated body, and the anode being arranged in this order.

7. A nonaqueous electrolyte secondary battery, comprising as a separator a laminated body according to claim 1 .

Assignees

• Sumitomo Chemical Co

Inventors

• Ogata Toshihiko
• Hashiwaki Hiroki
• Murakami Chikara

Classifications

• B32B27/20 Primary

  using fillers, pigments, thixotroping agents · CPC title

• B32B33/00

  Layered products characterised by particular properties or particular surface features, e.g. particular surface coatings; Layered products designed for particular purposes not covered by another single class · CPC title

• B32B27/304

  comprising vinyl halide (co)polymers, e.g. PVC, PVDC, PVF, PVDF · CPC title

• B32B2307/734

  Dimensional stability · CPC title

• B32B2266/0235

  Vinyl halide, e.g. PVC, PVDC, PVF, PVDF · CPC title