Tread

Claim 2

A tire, characterizing: a carcass; a tread adhered to said carcass; said tread having at least an inner layer having good heat resistant properties; said tread having at least an outer layer having good wear, cut and tear resistant properties; wherein said tread has from 3 to 10 layers, each of said tread layers containing one or more ingredients selected from the group consisting of natural cis 1,4 polyisoprene, carbon black, synthetic rubber, and hydrated amorphous silica; and wherein said tread layers are between 1/4 inch and 6 inches in thickness.

Claim 3

A tire according to Claim 1, wherein said tread has three layers, characterizing: said inner layer having a tear value of from about 830 to 1050 Newtons per inch, a rebound value of between about 82% and 96% and a Pico abrasion value of from about 70 and 90; a middle layer having a tear value of between about 1050 and 1290 Newtons per inch, a rebound value of from about 69% and 82%, and a Pico abrasion value of between about 84 and 104; and said outer layer having a tear value of between about 1230 and 1350 Newtons per inch, a rebound value of from about 64% and 74%, and a Pico abrasion value of from about 96 and 100..

Claim 4

A tire according to Claim 1, wherein said tread has six layers, comprising: said inner layer having a tear value of between about 830 and 1060 Newtons per inch, a rebound value of from about 82 and 96, and a Pico abrasion value of from about 70 and 90; a second innermost layer having a tear value of from about 1060 and 1200 Newtons per inch, a rebound value of from about 75 and 85, and a Pico abrasion value of from about 74 and 94; a third innermost layer having a tear value of from about 1190 and 1290 Newtons per inch, a rebound value of from about 69 and 81 and a Pico abrasion value of from about 84 and 104; a fourth innermost layer having a tear value of from about 1200 and 1330 Newtons per inch, a rebound value of from about 67 and 79, and a Pico abrasion value of from about 88 and 108; a fifth innermost layer having a tear value of from about 1230 and 1330 Newtons per inch, a rebound value of from about 65 and 76, and a Pico abrasion value of from about 92 and 100; and said outer layer having a tear value of from about 1230 and 1350 Newtons per inch, a rebound value of from about 64 and 74, and a Pico abrasion value of from about 96 and 112.

Claim 5

A tire according to Claim 1, wherein said tire has 3 layers and said inner layer has between about 70 and 100 PHR of a natural cis 1,4 polyisoprene; about between 30 and 0 PHR of synthetic rubber; between about 10 and 50 PHR of a low surface area carbon black; and between about 0 and 15 PHR of a hydrated amorphous silica; said outer layer has about between 0 and 30 PHR of a natural cis 1,4 polyisoprene; about between 70 and 100 PHR of synthetic rubber; about between 40 and 80 PHR of a high surface area carbon black; and about between 0 and 30 PHR of a hydrated amorphous silica; and wherein said tire has an intermediate layer having between about 30 and 75 PHR of a natural cis 1,4 polyisoprene; about between 70 and 25 PHR of synthetic rubber; about between 25 and 65 PHR of an intermediate surface area carbon black; and about between 0 and 20 PHR of a hydrated amorphous silica.

Claim 6

A tire according to Claim 1, wherein said tread has six layers, said inner layer having between about 95 and 100 PHR of natural cis 1,4 polyisoprene; between about 5 and 0 PHR of synthetic rubber; between about 20 and 40 PHR of a low surface area carbon black; and between about 0 and 15 PHR of a hydrated amorphous silica; and said outer layer having between about 0 and 5 PHR of natural cis 1,4 polyisoprene; between about 100 and 95 PHR of synthetic rubber; between' about 50 and 70 PHR of a high surface area carbon black; and between about 0 and 30 PHR of a hydrated amorphous silica; the second innermost layer having between about 80 and 95 PHR of natural cis 1,4 polyisoprene; between about 20 and 5 PHR of synthetic rubber; between about 25 and 45 PHR of a low surface area carbon black; and between about 0 and 15 PER of a hydrated amorphous silica; the third innermost layer having between about 60 and 80 PHR of natural cis 1,4 polyisoprene; between about 40 and 20 PHR of synthetic rubber; and between about 30 and 50 PHR of an intermediate surface area carbon black; and between about 0 and 20 PHR of a hydrated amorphous silica; the fourth innermost layer having between about 40 and 60 PHR of natural cis 1,4 polyisoprene; between about 60 and 40 PHR of synthetic rubber; between about 35 and 55 PHR of an intermediate surface area carbon black; and between about 0 and 20 PHR of a hydrated amorphous silica; and the fifth innermost layer having between about 5 and 40 PHR of natural cis 1,4 polyisoprene; between about 95 and 60 PHR of synthetic rubber; between about 45 and 65 PHR of a high surface area carbon black; and between about 0 and 30 PHR of a hydrated amorphous silica; and wherein said tread layers are each about 1- 1/2 inches thick and wherein said tire is an earth moving tire.

Claim 7

A process for making a tire having at least an inner tread composition and at least an .outer tread layer composition, characterizing the steps of: compounding said layer compositions ; calendering said layers to a sheet; wrapping said layers on a tire carcass; wherein said inner layer has good heat resistant properties and said outer layer has good wear, cut and tear resistant properties; wherein said tread layers contain one or more ingredients selected from the group consisting of natural cis 1,4 polyisoprene, carbon black, synethetic rubber, and hydrated amorphous silica; and wherein said tread has between 2 and about 10 layers.

Claim 8

A process for making a tire having at least an inner tread composition and at least an .outer tread layer composition, characterizing the steps of: compounding said layer compositions ; calendering said layers to a sheet; wrapping said layers on a tire carcass; wherein said inner layer has good heat resistant properties and said outer layer has good wear, cut and tear resistant properties; wherein said tread layers contain one or more ingredients selected from the group consisting of natural cis 1,4 polyisoprene, carbon black, synethetic rubber, and hydrated amorphous silica; and wherein said tread has between 2 and about 10 layers.

Claim 9

A process according to Claim 6, wherein said tire has 3 layers, said inner layer having between about 70 and 100 PHR of a natural cis 1,4 polyisoprene; about between 30 and 0 PHR of synthetic rubber; between about 10 and 50 PHR of a low surface area carbon black; said outer layer having about between 0 and 30 PHR of a natural cis 1,4 polyisoprene; about between 70 and 100 PHR of a synthetic rubber; about between 40 and 80 PHR of a high surface area carbon black; and about between 0 and 30 PHR of a hydrated amorphours silica; and wherein said tread has an intermediate layer having from about 30 and 75 PHR of a natural cis 1,4 polyisoprene; about between 70 and 25 PHR of synthetic rubber; about between 25 and 65 PHR of an intermediate surface area carbon black; and about between 0 and 20-PHR of a hydrated amorphous silica.

Claim 10

A process according to Claim 6, wherein said tread has six layers, said inner layer having between about 95 and 100 PHR of a natural cis 1, 4 polyisoprene; between about 5 and 0 PHR of synthetic rubber; between about 20 and 40 PHR of a low surface area carbon black; and between about 0 and 15 PHR of a hydrated amorphous silica; said outer layer has between about 0 and 5 PHR of.natural cis 1,4 polyisoprene; between about 100 and 95 PHR of synthetic rubber; between about 50 and 70 PHR of a high surface area carbon black; and between about 0 and 30 PHR of a hydrated amorphous silica.

Claim 11

A process according to Claim 8, wherein the second innermost layer has between about 80 and 95 PHR of natural cis 1,4 polyisoprene; between about 20 and 5 PHR of synthetic rubber; between about 25 and 45 PHR of a low surface area carbon black; and between about 0 and 15 PHR of a hydrated amorphous silica; wherein the third innermost layer has between about 60 and 80 PHR of natural cis 1,4 polyisoprene; between about 40 and 20 PHR of synthetic rubber; between about 30 and 50 PHR of an internediate surface area carbon black; and between about 0 and 20 PHR of a hydrated amorphous silica; wherein said fourth innermost layer has between about 40 and 60 PHR of natural cis 1,4 polyisoprene; between about 60 and 40 PHR of synthetic rubber; between about 35 and 55 PHR of an intermediate surface area carbon black; and between about 0 and 20 PHR of a hydrated amorphous silica; wherein the fifth innermost layer has between about 5 and 40 PHR of natural cis 1,4 polyisoprene; between-about 95 and 60 PHR of synthetic rubber; between about 45 and 65 PHR of a high surface . area carbon black; and between about 0 and 30 PHR of a hydrated amorphous silica.

Claim 12

A process according to Claim:9, including milling said layer compositior, and cold feed extruding said layer composition before calendering said layer into a sheet; wherein said tread layers are each about 1 - 1/2 inches thick and said tire is an earth moving tire.