Stress and/or temperature-indicating composition for roll covers
View Patent ↗An industrial roll includes: a substantially cylindrical core and a cover overlying the adhesive layer. The cover typically comprises a polymeric top stock layer which comprises a mixture of a polymeric material and at least one of a piezochromic material and a thermochromic material. In this configuration, the pressure and/or temperature experienced by the roll cover at any location thereon can be determined visually, without the need for external equipment.
1. An industrial roll, comprising:
a substantially cylindrical core; and
a cover overlying said core, said cover comprising a layer overlying said core comprising a mixture of a polymeric material and a piezochromic material, wherein the mixture further comprises 100 parts polymeric material by weight and between about 0.001 and 10 parts thermocbromic material by weight.
2. The roll defined in claim 1 , wherein the cover comprises a top stock layer, and wherein the top stock layer is the layer comprising the mixture of a polymeric material and a piezochromic material and a thermochromic material.
3. The roll defined in claim 2 , wherein the cover further comprises a base layer, the base layer overlying the core and underlying the top stock layer.
4. The roll defined in claim 3 , wherein the cover further comprises a tie-in layer between the base layer and the top stock layer.
5. The roll defined in claim 1 , wherein the thermochromic material is selected and included in an amount such that it displays an identifiable color change at a temperature of between about 40 and 180 degrees C.
6. The roll defined in claim 1 , wherein the mixture comprises 100 parts polymeric material by weight and between about 0.001 and 10 parts piezochromic material by weight.
7. The roll defined in claim 1 , wherein the polymeric material comprises a rubber material.
8. The roll defined in claim 1 , wherein the piezochromic material is selected and included in an amount such that it displays an identifiable color change at a pressure of between about 1450 and 15,000 psi.
9. The roll defined in claim 1 , further comprising an adhesive layer between the core and the cover.
10. The roll defined in claim 1 , wherein the layer comprising the mixture is an intermediate layer overlying the core, and wherein the cover comprises a transparent top stock layer that overlies the intermediate layer.
11. An industrial roll, comprising:
a substantially cylindrical core; and
a cover overlying said core, said cover comprising a layer overlying said core comprising a mixture of a polymeric material and a thermochromic material, and further comprising a dye-developer, a fluxing agent, and an interfacially-active substance.
12. The roll defined in claim 11 , wherein the cover comprises a top stock layer, and wherein the top stock layer is the layer comprising the mixture of a polymeric material and a thermochromic material.
13. The roll defined in claim 12 , wherein the cover further comprises a base layer, the base layer overlying the core and underlying the top stock layer.
14. The roll defined in claim 13 , wherein the cover further comprises a tie-in layer between the base layer and the top stock layer.
15. The roll defined in claim 11 , wherein the mixture comprises 100 parts polymeric material by weight and between about 0.001 and 10 parts thermochromic material by weight.
16. The roll defined in claim 11 , wherein the polymeric material comprises a rubber material.
17. The roll defined in claim 11 , wherein the thermochromic material is selected and included in an amount such that it displays an identifiable color change at a temperature of between about 40 and 180 degrees C.
18. The roll defined in claim 11 , further comprising an adhesive layer between the core and the cover.
19. The roll defined in claim 11 , wherein the layer comprising the mixture is an intermediate layer overlying the core, and wherein the cover comprises a transparent top stock layer that overlies the intermediate layer.