{
  "$type": "site.standard.document",
  "description": "A heavy duty tire comprising a tread part, wherein the tread part comprises a plurality of circumferential grooves extending continuously in a tire circumferential direction, wherein the tread part at least comprises three rubber layers, wherein a tan δ at 70°C of the rubber composition…",
  "path": "/patents/1393609",
  "publishedAt": "2026-02-04T00:00:00.000Z",
  "site": "at://did:plc:oql6ds5vnff4ugar6rruliwd/site.standard.publication/3mn3ohu7oxx5w",
  "tags": [
    "B60C11/005",
    "SUMITOMO RUBBER IND [JP]"
  ],
  "textContent": "A heavy duty tire comprising a tread part, wherein the tread part comprises a plurality of circumferential grooves extending continuously in a tire circumferential direction, wherein the tread part at least comprises three rubber layers, wherein a tan δ at 70°C of the rubber composition constituting the first layer is smaller than a tan δ at 70°C of the rubber composition constituting the second layer, and wherein, when a tire outer diameter is defined as Dt, in m, a thickness of the first layer is defined as t1, in mm, and a groove depth at a deepest part of the circumferential grooves is defined as H, in mm, 70°C tan δ2/Dt is greater than 0.09, and t1/H is 0.90 or less.",
  "title": "HEAVY DUTY TIRE"
}