{
  "$type": "site.standard.document",
  "description": "As a porous film in which the air-permeability at the time of elongation of the porous film was adjusted, whereby, when used as a battery separator, the holes of a separator in an electrode/separator wound body have been controlled, a polypropylene series resin porous film is proposed, in which…",
  "path": "/patents/993667",
  "publishedAt": "2013-01-23T00:00:00.000Z",
  "site": "at://did:plc:oql6ds5vnff4ugar6rruliwd/site.standard.publication/3mn3ohu7oxx5w",
  "tags": [
    "B32B27/08",
    "MITSUBISHI PLASTICS INC [JP]"
  ],
  "textContent": "As a porous film in which the air-permeability at the time of elongation of the porous film was adjusted, whereby, when used as a battery separator, the holes of a separator in an electrode/separator wound body have been controlled, a polypropylene series resin porous film is proposed, in which, for a porous film having a polypropylene series resin as the main component, regarding air-permeability (Pa) prior to elongation and air-permeability (Pa') at 5% elongation, (1) Pa'is 1,000 seconds/100 ml or less and (2) Pa'/Pa is 1.5 or less.",
  "title": "POROUS POLYPROPYLENE RESIN FILM, SEPARATOR FOR USE IN A BATTERY, AND BATTERY"
}