发明名称 |
AUTOMOBILE PNEUMATIC TIRE AND MANUFACTURE THEREOF |
摘要 |
PROBLEM TO BE SOLVED: To mitigate setting conditions for reduction of rolling resistance and improvement of steering stability by making a tread part into a two-layer structure of a cap tread layer and under-tread layer. SOLUTION: An under tread layer 4b is composed of a center area in a range of 30 to 70% of a width of a belt layer 5a and 0.5 to 2.0 mm from the belt layer 5b in a tire diametral direction, and a shoulder area continuing from the center area and in a range extended outside from both ends of the belt layer 5a at a maximum 30 mm on one side and width of 1.0 to 5.0 mm, made of mutually different rubber compositions. A rubber layer 4b1 with a JIS-A hardness in a range of 65 to 80 degrees and a mixed amount of softening agent ten parts by weight or more lesser than a cap tread layer 4a is arranged in the center area. A rubber layer 4b2 with a JIS-A hardness in a range of 50 to 70 degrees and a mixed amount of softening agent ten parts by weight or more lesser than the cap tread layer 4a is arranged in the shoulder area. A ratio of a loss tangent of the rubber layer 4b2 of the shoulder area to a loss tangent of the rubber layer 4b1 is two thirds or less. |
申请公布号 |
JP2000198319(A) |
申请公布日期 |
2000.07.18 |
申请号 |
JP19980374206 |
申请日期 |
1998.12.28 |
申请人 |
YOKOHAMA RUBBER CO LTD:THE |
发明人 |
IIDA HIDEKAZU;AMINO NAOYA;TAKASUGI MOTOHIDE |
分类号 |
B29C45/00;B29C47/00;B29D30/08;B29D30/60;B29D30/70;B29L30/00;B60C1/00;B60C11/00;(IPC1-7):B60C11/00 |
主分类号 |
B29C45/00 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|