Title:
STUDLESS TIRE OF LESS CHANGE IN HARDNESS
Document Type and Number:
Japanese Patent JPS6430806
Kind Code:
A
Abstract:
PURPOSE:To reduce change in hardness by arranging an oil barrier having a specific ratio of compound polymer of halogenated butyl rubber between a tread and a belt. CONSTITUTION:An oil barrier is arranged between a tread and a belt to prevent a softening agent containing a low temperature plasticizer in the tread rubber from moving to the belt. At least 30 weight % of the polymer to be compounded into the oil barrier is substituted with halogenated butyl rubber such as chlorinated butyl rubber, brominated butyl rubber, etc. A high viscosity petroleum-based aromatic plasticizer which moves less in rubber is compounded in the barrier ply rubber at a volumetric content of at least about 40% of the total of liquid state compounding agent such as softening agent, plasticizer, etc., of the tread rubber. At the same time, the concentration gradient of the softening agent in the tread rubber and the barrier ply rubber are made small. Changes in hardness are thus restricted.
Inventors:
SUGA MASANORI
Application Number:
JP18815887A
Publication Date:
February 01, 1989
Filing Date:
July 27, 1987
Export Citation:
Assignee:
TOYO TIRE & RUBBER CO
International Classes:
B29D30/52; B60C11/00; (IPC1-7): B29D30/52; B60C11/00
Attorney, Agent or Firm:
Iwao Tamura