Biaxially-oriented porous film

A porous membrane, biaxial stretching technology, applied in membrane technology, semi-permeable membrane separation, non-aqueous electrolyte and other directions, can solve the problems of easy membrane breakage, durability and reliability of biaxially oriented membrane, and easy breakage. , to achieve the effect of excellent homogeneity, high strength and small pore size

Active Publication Date: 2016-07-20
DAIKIN IND LTD
View PDF41 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] However, the thickness of the biaxially stretched polytetrafluoroethylene film is thin (usually 100 μm or less), and the film is easily broken during the stretching process or in the post-stretching process after stretching, lamination, etc.
Furthermore, when used as clothing or a separation membrane, it is also easy to break, and there are problems in the durability and reliability of the biaxially stretched film.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Biaxially-oriented porous film
  • Biaxially-oriented porous film
  • Biaxially-oriented porous film

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0430] (extrusion and calendering)

[0431] With respect to 100 parts by weight of fine powder A (PTFE-A) of modified PTFE obtained in Production Example 1, 28 parts by weight of hydrocarbon oil ("IP solvent 2028" manufactured by Idemitsu Kosan Co., Ltd.) was added as an extrusion aid and mixed and allowed to stand for 12 hours.

[0432] Next, the mixture of the fine powder A (PTFE-A) and the extrusion aid was put into a 100φmm preforming machine, and compressed at a pressure of 3 MPa to obtain a preform. Next, the above-mentioned preform was placed in an extruder with an inner diameter of 100 mm previously provided with a die with an inner diameter of 16 mmφ, and paste extrusion was performed to obtain a PTFE molded body.

[0433] Furthermore, the obtained PTFE molded body was molded (calendered) into a film shape by calender rolls to obtain an unfired PTFE film.

[0434] The hydrocarbon oil was evaporated and removed by a hot air drying furnace to obtain a strip-shaped unf...

Embodiment 2~5 and comparative example 1~4

[0459] Except having changed the kind of PTFE raw material and the quantity of an extrusion aid (hydrocarbon oil) as described in Table 2, it processed similarly to Example 1, and obtained the porous film (biaxially-stretched film).

[0460] Various physical properties were measured in the same manner as in Example 1. The results are listed in Table 2.

[0461] In Examples 1 to 5, a homogeneous and high-strength biaxially stretched film was obtained. The biaxially stretched films obtained in Comparative Examples 1 and 2 were homogeneous but inferior in strength.

[0462] In Comparative Example 3, the round bar-shaped PTFE molded body obtained by paste extrusion was hard, and thus had poor calenderability, cracks occurred in the rolled product, and a homogeneous unfired PTFE film could not be obtained. In Comparative Example 4, even if the amount of extrusion aid was increased in order to lower the extrusion pressure, the obtained biaxially oriented film was poor in homogenei...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
breaking strengthaaaaaaaaaa
particle diameteraaaaaaaaaa
particle sizeaaaaaaaaaa
Login to view more

Abstract

The purpose of the invention is to provide a biaxially-oriented porous film that is strong, has a small pore size, and exhibits superior homogeneity. The invention relates to a biaxially-oriented porous film characterized by comprising a polytetrafluoroethylene obtained from the copolymerization of tetrafluoroethylene and perfluoro(methyl vinyl ether).

Description

technical field [0001] The present invention relates to a biaxially oriented porous film. Background technique [0002] It is known that a porous body having a high porosity can be obtained by stretching a molded body obtained by paste extrusion molding polytetrafluoroethylene fine powder. The polytetrafluoroethylene porous body is composed of nodes (nodules) and fibrils (fibers), through which gases such as water vapor can pass, but since polytetrafluoroethylene is highly water-resistant, water droplets cannot pass therethrough. The porous stretched body is used as a sealing material in an unfired state, or it is fired to form a strong continuous stretched sheet or tube, which is applied to clothing or a separation membrane. [0003] In particular, biaxially oriented porous films (biaxially oriented films) have been used in a wide range of fields such as gas / liquid (including reagent) microfilters, electric wire coating materials, and breathing valves. [0004] However, t...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C08J9/00H01M8/1023H01M8/1039H01M8/1069
CPCB01D67/0027B01D71/36B01D71/76C08J5/18C08J2327/18H01M8/1023H01M8/1039H01M8/1079H01M2300/0082Y02E60/50Y02P70/50B01D71/52
Inventor 茶圆伸一山中拓安田幸平山田雅彦浦冈伸树小西智久乾邦彦涉谷吉之小野真诚
Owner DAIKIN IND LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products