Vulcanization system containing a three-component accelerator system

Claim 2

A SULFUR VULCANIZABLE RUBBER CONTAINING 0.00 TO 3.25 PARTS BY WEIGHT OF FREE SULFUR PER 100 PARTS BY WEIGHT OF RUBBER AND 0.5 TO 5.50 PARTS BY WEIGHT PER WEIGHT OF RUBBER, OF AN ACCELERATOR SYSTEM COMPRISING A. 2-(MORPHOLINODITHIO)-BENZOTHIAZOLE, B. AT LEAST ONE BENZOTHIAZOLE ACCELERATOR HAVING THE FOLLOWING STRUCTUAL FORMULA

Claim 3

A sulfur vulcanizable rubber containing 0.00 to 3.25 parts by weight of free sulfur per 100 parts by weight of rubber and 0.5 to 5.50 parts by weight per 100 parts by weight of rubber, of an accelerator system comprising A. 2-(morpholinodithio)-benzothiazole, B. at least one benzothiazole accelerator selected from the group consisting of 2-(morpholinothio)-benzothiazole, N-(cyclohexyl)-2-benzothiazolesulfenamide, N-(t-butyl)-2-benzothiazolesulfenamide, N,N-(diisopropyl)-2-benzothiazolesulfenamide, 2-(3,6-dimethylmorpholinothio)-benzothiazole, N,N-(diethyl)-2-benzothiazolesulfenamide, N-(octyl)-2-benzothiazolesulfenamide, and 2-(3-methylpiperidinothio)-benzothiazole, and C. 4,4''-dithiomorpholine wherein the weight ratio A/B/C is 20 to 70/10 to 60/10 to 60 based on 100 parts by weight of A, B and C, and wherein the total weight of sulfur plus accelerator system is from 2.25 to 5.50 parts by weight per 100 parts by weight of rubber.

Claim 4

A sulfur vulcanizable rubber containing 0.00 to 3.25 parts by weight of free sulfur per 100 parts by weight of rubber and 0.5 to 5.50 parts by weight per 100 parts by weight of rubber, of an accelerator system comprising A. 2-(morpholinodithio)-benzothiazole, B. at least one benzothiazole accelerator selected from the group consisting of 2-(morpholinothio)-benzothiazole, N-(cyclohexyl)-2-benzothiazolesulfenamide, N-(t-butyl)-2-benzothiazolesulfenamide, N,N-(diisopropyl)-2-benzothiazolesulfenamide, 2-(3,6-dimethylmorpholinothio)-benzothiazole, N,N-(diethyl)-2-benzothiazolesulfenamide, N-(octyl)-2-benzothiazolesulfenamide, and 2-(3-methylpiperidinothio)-benzothiazole, and C. 4,4''-dithiomorpholine wherein the weight ratio A/B/C is 20 to 70/10 to 60/10 to 60 based on 100 parts by weight of A, B and C, and wherein the total weight of sulfur plus accelerator system is from 2.25 to 5.50 parts by weight per 100 parts by weight of rubber.

Claim 5

The sulfur vulcanizable rubber according to claim 1 wherein R3 is hydrogen.

Claim 6

The sulfur vulcanizable rubber according to claim 1 wherein the sulfur level is from 0.10 to 1.25 parts.

Claim 7

The sulfur vulcanizable rubber according to claim 1 wherein the sulfur level is from 1.25 to 3.25 parts.

Claim 8

The sulfur vulcanizable rubber according to claim 1 containing as an accelerator a compound selected from the group consisting of N-(cyclohexyl)-2-benzothiazylsulfenamide and 2-(morpholinothio)-benzothiazole.

Claim 9

The sulfur vulcanizable rubber according to claim 1 wherein A comprises 30 to 60 percent, B comprises 20 to 40 percent and C comprises 20 to 40 percent by weight of the three-component accelerator system.

Claim 10

A process of preparing a rubbery vulcanizate comprising heating the sulfur vulcanizable rubber of claim 1 at a vulcanizing temperature.