Semi-conductive layer-containing reinforced pressure hose and method of making same

Claim 2

A flexible hose for conveying and spraying a fluid which comprises a core tube through which the fluid flows under pressure, said core tube having a laminated wall with a first extruded lamina of a synthetic polymer adjacent to the fluid which resists chemical attack by the fluid and which conducts static electricity radially outwardly from the fluid and a second lamina disposed radially outwardly about the first lamina, said second lamina being a semi-conductive polymer which is in electrical contact with the first lamina, said semi-conductive polymer being a cross-linked polymer, said laminae being co-extensive throughout the length of the hose, at least one layer of fibrous material disposed about the core tube and reinforcing it against bursting under pressure from the fluid, a substantially non-electrical conducting synthetic polymer sheath about the said fibrous material, and a spray nozzle on one end of the hose in electrical conducting contact with said semi-conductive lamina and electrically connected to ground.

Claim 3

The flexible hose of claim 1 wherein the outer semi-conductive layer is an extruded layer.

Claim 4

The flexible hose of claim 1 wherein the extruded inner layer and semi-conductive outer layer are melt fused to provide the intimate contact therebetween.

Claim 5

The flexible hose of claim 1 wherein the synthetic polymeric material of the extruded inner layer is a nylon and the cross-linked semi-conductive outer layer material is a polyurethane.

Claim 6

The flexible hose of claim 1 wherein the semi-conductive outer layer polymeric material contains carbon particles.

Claim 7

The flexible hose of claim 1 wherein the outer layer of cross-linked semi-conductive polymeric material has an electrical volume resistivity at 20° C. of not more than about 2000 ohm-cm.

Claim 8

The flexible hose of claim 1 wherein the polymeric material of the inner layer is a nylon and the outer semi-conductive layer is an extruded layer of a polyurethane composition containing carbon particles.

Claim 9

The flexible hose of claim 1 wherein the fibrous reinforcement is bonded to the outer semi-conductive polymeric layer.

Claim 10

The flexible hose of claim 1 having more than one layer of fibrous reinforcement and the adjacent layers thereof are bonded together.

Claim 11

The flexible hose of claim 1 wherein the polymeric material is an extruded polyurethane.

Claim 12

The flexible hose of claim 1 wherein the polymeric material of the sheath is a cross-linked polymeric material.

Claim 13

The flexible hose of claim 1 wherein the cross-linked polymeric material of the semi-conductive outer layer is a radiation cross-linked material.

Claim 14

The flexible hose of claim 12 wherein the radiation cross-linked semi-conductive layer is a high energy electron radiation cross-linked material.

Claim 15

The flexible hose of claim 1 wherein the polymeric material of the sheath is an irradiation cross-linked material.

Claim 16

The flexible hose of claim 14 wherein the radiation cross-linked polymeric material of the sheath is a high energy electron radiation cross-linked material.

Claim 17

The flexible hose of claim 1 wherein the polymeric material of the inner layer is a cross-linked material.

Claim 18

The flexible hose of claim 16 wherein the cross-linked polymeric material of the inner layer is a radiation cross-linked material.

Claim 19

The flexible hose of claim 17 wherein the cross-linked polymeric material of the inner layer is a high energy electron cross-linked material.

Claim 20

In a method of making a flexible reinforced hose for conveying fluids under pressure comprising a composite core tube, one or more layers of fibrous reinforcing material disposed about the core tube and a substantially electrically non-conductive polymeric protective sheath disposed about the reinforcement material, said core tube having a laminated wall with a first extruded lamina of a synthetic polymer adjacent to the fluid which resists chemical attack by the fluid and which conducts static electricity radially outwardly from the fluid and a second lamina disposed radially outwardly about the first lamina, said second lamina being a semi-conductive polymer which is in electrical contact with the first lamina, said semi-conductive polymer being a cross-linked polymer, said laminae being co-extensive throughout the length of the hose, the method including the steps of: (a) Extruding an inner layer of a suitable flexible synthetic polymeric material into an elongate tubular shaped form; (b) Forming an outer tubular shaped layer of cross-linkable semi-conductive synthetic polymeric material coextensively about and in intimate contact with the inner layer; (c) Exposing the outer semi-conductive layer to an amount of radiation sufficient to cross-link the material; (d) Disposing one or more layers of fibrous reinforcement about the outer semi-conductive layer; and (e) Forming a protective sheath about the fibrous reinforcement material.

Claim 21

In a method of making a flexible reinforced hose for conveying fluids under pressure comprising a composite core tube, one or more layers of fibrous reinforcing material disposed about the core tube and a substantially electrically non-conductive polymeric protective sheath disposed about the reinforcement material, said core tube having a laminated wall with a first extruded lamina of a synthetic polymer adjacent to the fluid which resists chemical attack by the fluid and which conducts static electricity radially outwardly from the fluid and a second lamina disposed radially outwardly about the first lamina, said second lamina being a semi-conductive polymer which is in electrical contact with the first lamina, said semi-conductive polymer being a cross-linked polymer, said laminae being co-extensive throughout the length of the hose, the method including the steps of: (a) Extruding an inner layer of a suitable flexible synthetic polymeric material into an elongate tubular shaped form; (b) Forming an outer tubular shaped layer of cross-linkable semi-conductive synthetic polymeric material coextensively about and in intimate contact with the inner layer; (c) Exposing the outer semi-conductive layer to an amount of radiation sufficient to cross-link the material; (d) Disposing one or more layers of fibrous reinforcement about the outer semi-conductive layer; and (e) Forming a protective sheath about the fibrous reinforcement material.

Claim 22

The method of claim 19 wherein the cross-linkable semi-conductive outer layer is formed by extrusion.

Claim 23

The method of claim 19 wherein the intimate contact is provided by melt fusing the outer semi-conductive layer to the inner synthetic polymeric layer.

Claim 24

The method of claim 19 wherein the radiation is provided by high energy electrons.

Claim 25

The method of claim 19 wherein the outer protective sheath is formed by extrusion.

Claim 26

The method of claim 19 wherein the semi-conductive outer layer is exposed to radiation after the fibrous reinforcement has been disposed thereabout.

Claim 27

The method of claim 19 wherein the semi-conductive outer layer is exposed to radiation after the outer protective sheath has been formed about the fibrous reinforcement.

Claim 28

The method of claim 19 wherein the polymeric material of the inner layer is a nylon.

Claim 29

The method of claim 19 wherein the semi-conductive material of the outer layer is a polyurethane.

Claim 30

The method of claim 19 wherein the outer layer of semi-conductive material has an electrical volume resistivity at 20° C. of not more than about 2000 ohm-cm.

Claim 31

The method of claim 19 wherein the outer layer of semi-conductive material contains carbon particles.

Claim 32

The method of claim 19 wherein the fibrous reinforcement is bonded to the semi-conductive outer layer during the process of making the hose.