Tire treads and their manufacture

The process of preparing a tire tread the tread stock for which includes rubber which is curable by electron irradiation and curable by sulfur and heat which process comprises at least partially curing at least a portion of said tread stock by exposure to electron irradiation or other means of radiation having the same curing effect on the exposed rubber and thereafter assembling said tire tread with other tire elements and curing said portion by sulfur and heat.

The process of preparing a tire which comprises winding onto a carcass a length of tread stock which is treated with electron radiation or other means of radiation having the same curing effect on the exposed rubber, and by relative rotation between the tread and a source of such treatment, progressively curing the tread as it is wound onto the carcass and the successive layers are adhered to one another, and continuing the progressive curing by such treatment until the last layer of the tread is wound onto the carcass and cured.

An unfinished tire having a green tread at least a portion of the thickness of which is curable by electron irradiation or other means of radiation having the same curing effect on the exposed rubber, at least a portion of the thickness of which green tread has been only partially cured by exposure to such irradiation and contains sufficient chemical curing ingredients for completion of cure.

A pneumatic tire the tread of which is not completely cured, a portion of the thickness of the tread adjacent the carcass comprising rubber curable by electron irradiation and which portion is at least partially cured by exposure to said irradiation, at least most of the exposed surface of the tread being uncured or cured to a lesser extent than said portion adjacent the carcass.

A green tire no part of which is completely cured, and the major parts of which contain an unreacted curing agent, and at least a portion of the tread of which has been partially cured by exposure to electron irradiation or other means of radiation having the same curing effect on the exposed rubber.

The process of preparing a tread for a pneumatic tire which includes rubber containing sulfur which rubber is curable by exposure to electron irradiation or other means of radiation having the same curing effect on the exposed rubber, which process comprises effecting the curing of said tread by a combination of curing processes, first partially curing at least a portion of said rubber by exposure to electron irradiation or other means of radiation having the same curing effect on the exposed rubber and thereafter curing said rubber with heat and sulfur.

The process of preparing a molded tread for a tire which tread includes rubber curable by exposure to electron irradiation or other means of radiation having the same curing effect on the exposed rubber, which process comprises after said rubber has been incorporated in a tread stock treating and thereby partially curing at least a portion of said rubber by exposure to said irradiation and thereafter placing said tread stock in a mold.

The process of preparing a tread for a tire which tread includes rubber curable by exposure to electron irradiation or other means of radiation having the same curing effect on the exposed rubber, which process comprises after said rubber has been incorporated in the tread stock partially curing said rubber by exposure to said irradiation and thereafter curing the tread in a mold.

The process of preparing a tread for a tire the green tread for which includes rubber which is curable by electron irradiation which process comprises at least partially curing at least a portion of said green tread on the carcass by exposure to electron irradiation or other means of radiation having the same curing effect on the exposed rubber before molding of the assembled thread.

The process of preparing a tread for a tire the green tread for which includes rubber which is curable by electron irradiation and curable by sulfur and heat which process comprises at least partially curing at least a portion of said green tread by exposure to electron irradiation or other means of radiation having the same curing effect on the exposed rubber and thereafter curing said green tread rubber by sulfur and heat.