Patent · US Expired

Pneumatic tire for automobile and its fabrication method

US6412532B1 · kind B1 · utility

10Cited by
9References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 23, 1999
Grant dateJul 2, 2002
Priority date
Expiry dateDec 23, 2019

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02T10/86
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A pneumatic tire for an automobile having a tread portion in a two-layered structure of a cap tread layer and an under tread layer, in which the under tread layer is constituted by a center region defined by a range of 30 through 70% of a width of a first belt layer and up to 0.5 through 2.0 mm in a tire diameter direction from a second belt layer and a shoulder region extended from both end portions of the first belt layer continuously from the center region to an outer side by 30 mm at maximum on one side and having a thickness of 1.0 through 5.0 mm, the regions comprising rubber composition members different from each other, the center region is arranged with a rubber layer where JIS-A hardness falls in a range of 65 through 80 and an amount of blending a softening agent relative to rubber 100 weight parts is smaller than that of the cap tread layer by 10 weight parts or more, the shoulder region is arranged with a rubber layer where JIS-A hardness falls in a range of 50 through 70 and the amount of blending the softening agent relative to rubber 100 weight parts is smaller than that of the cap tread layer by 10 weight parts or more and a ratio (tan &dgr;2/tan &dgr;1) of loss ta…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.