{
  "$type": "site.standard.document",
  "description": "The present invention relates to a high tenacity polyethylene naphthalate fiber containing a silica compound. This fiber is produced by a method comprising the steps of: (A) melt-spinning a solid phase-polymerized polyethylene-2,6-naphthalate chip containing ethylene-2,6-naphthalate units at more…",
  "path": "/patents/1081044",
  "publishedAt": "2005-01-05T00:00:00.000Z",
  "site": "at://did:plc:oql6ds5vnff4ugar6rruliwd/site.standard.publication/3mn3ohu7oxx5w",
  "tags": [
    "B60C9/0042",
    "HYOSUNG CORP [KR]"
  ],
  "textContent": "The present invention relates to a high tenacity polyethylene naphthalate fiber containing a silica compound. This fiber is produced by a method comprising the steps of: (A) melt-spinning a solid phase-polymerized polyethylene-2,6-naphthalate chip containing ethylene-2,6-naphthalate units at more than 85 mole% and a silica compound and having an intrinsic viscosity of 0.70-1.20, to produce a melt-spun yarn; (B) passing the melt-spun yarn through a retarded cooling zone and a cooling zone to solidify the yarn; (C) withdrawing the yarn at such a speed that the undrawn yarn has a birefringence of 0.001-0.1; and (D) subjecting the undrawn yarn to multi-stage drawing at a total draw ratio of at least 1.5 and a drawing temperature of 50-250 °C. The polyethylene naphthalate fiber has improved physical properties, such as high tenacity, and a dipped cord produced from this fiber has excellent dimensional stability and tenacity such that it can be advantageously employed as a reinforcement material of rubber products.",
  "title": "High tenacity polyethylene-2,6-naphthalate fibers"
}