Root-growth-inhibiting sheet

Claim 2

A material for preventing the entry of roots into unwanted areas comprising a sheet of water-permeable material; characterised in that the sheet material carries distributed bodies of a polymer blended with from 2 to 30 percent of a 2,6-dinitroaniline; wherein the dinitroaniline is released slowly from the distributed bodies by diffusion from the polymer into the soil juxtaposed the material, thereby to prevent elongation or penetration of the roots into the soil around the material.

Claim 3

A material as defined in claim 1 wherein said dinitroaniline is trifluralin.

Claim 4

A material as defined in claim 1 or claim 2 wherein said sheet is flexible.

Claim 5

A material as defined in any preceding claim wherein said sheet is formed of a non-biodegradable composition.

Claim 6

A material as defined in any preceding claim wherein said sheet is a nonwoven fabric of a non-biodegradable polymeric composition.

Claim 7

A material as defined in any preceding claim wherein said polymer is blended further with an amount of carbon black sufficient to improve retention of said dinitroaniline.

Claim 8

A material as claimed in claim 6 wherein the concentration of carbon black is about 25 percent.

Claim 9

A material as defined in any preceding claim wherein said polymer is polyethylene.

Claim 10

A material as defined in any preceding claim wherein said polymer is in the form of buttons attached to, and distributed over, said sheet.

Claim 11

A material as defined in claim 9, wherein said buttons are 6.3 to 9.45mm (1/4 to 3/8 inch) in diameter and 3.15 to 9.45mm (1/8 to 3/8 inch) maximum thickness.

Claim 12

Material as defined in claim 9 or 10 wherein said buttons to 3 inc

Claim 13

An wherein 5

Claim 14

An wherein 5

Claim 15

An are 0.15 to 6.3mn

Claim 16

An are 0.15 to 6.3mn

Claim 17

An unwantec 10 with ref Descript DATED t i a. a. r 7 i I 6 buttons are spaced apart an average of 2.52 to 7.56 cms (1 to 3 inches). 12. A material as defined in any one of claims 1 to 8 wherein said polymer is in the form of elongated beads. 13. A material as defined in claim 12 wherein said beads are 0.158 to 0.63 cm (1/16 to 1/4 inch) wide and from 1.57 to 6.3mms (1/16 to 1/4 inch) in maximum thickness. 14. A material for preventing the entry of roots into unwanted areas substantially as hereinbefore described with reference to the description entitled "Detailed Description". DATED this 16 day of June 1992 BATTELLE MEMORIAL INSTITUTE Patent Attorneys for the Applicant: F.B. RICE CO. a e e *s