Process for high-speed extrusion coating using a composition containing a linear low density ethylene hydrocarbon copolymer

Claim 2

1) In a process for the extrusion coating of a substrate with a high pressure, low density polyethylene homopolymer or copolymer extrusion coating composition, the improvement which comprises: using as said composition one comprising more than 20 and less than 98 weight percent, preferably between about 30 and 90 weight percent of said high pressure, low density polyethylene homopolymer and/or copolymer and more than 2 and less than 80 weight percent, preferably between about 10 and 70 weight percent of at least one linear low density ethylene hydrocarbon copolymer.

Claim 3

2) In a process for applying an extruded coating to a substrate at. a temperature of at least 232 0 C (450°F)wherein a coating composition containing a high pressure, low density polyethylene homopolymer or.copolymer is fed into an extruder and converted into an extrudate which is drawn-down onto a substrate to coat said substrate, said coating being essentially free of pinholes and having a thickness below about 0.013 mm (0.5 mils), the improvement which comprises: using as said coating composition one comprising more than 20 and less than 98 weight percent, preferably between about 30 and 90 weight percent of said high pressure, low density polyethylene homopolymer and/or copoly mer and more than 2 and less than 80 weight percent, pre ferably between about 10 and 70 weight percent of a linear, low density ethylene hydrocarbon copolymer; and operating said extruder at coating speeds greater than 183 m (600 feet) per minute to apply said coating to said substrate, in the absence of neck-in greater than about 7.6 cm (3 inches).

Claim 4

2) In a process for applying an extruded coating to a substrate at. a temperature of at least 232 0 C (450°F)wherein a coating composition containing a high pressure, low density polyethylene homopolymer or.copolymer is fed into an extruder and converted into an extrudate which is drawn-down onto a substrate to coat said substrate, said coating being essentially free of pinholes and having a thickness below about 0.013 mm (0.5 mils), the improvement which comprises: using as said coating composition one comprising more than 20 and less than 98 weight percent, preferably between about 30 and 90 weight percent of said high pressure, low density polyethylene homopolymer and/or copoly mer and more than 2 and less than 80 weight percent, pre ferably between about 10 and 70 weight percent of a linear, low density ethylene hydrocarbon copolymer; and operating said extruder at coating speeds greater than 183 m (600 feet) per minute to apply said coating to said substrate, in the absence of neck-in greater than about 7.6 cm (3 inches).

Claim 5

3) A process as defined in claims 1 or 2 wherein said high pressure, low density polyethylene homopolymer or copolymer has a melt index between about 1 and about 20, pre ferably between about 2 and about 6.

Claim 6

4) A process as defined in claims 1 or 2 wherein said high pressure, low density polyethylene copolymer is a copolymer or ethylene/ethyl acrylate and ethylene/vinyl acetate having a melt index between about 2 and about 6.

Claim 7

5) A process as defined in any one of claims 1 - 4 wherein the high pressure, low density polyethylene homopolymer or copolymer is present in an amount between about 40 and 80 weight percent, and said linear low density ethylene hydrocarbon copolymer is present in an amount between about 20 and 60 weight percent.

Claim 8

6) A process as defined in any one of the claims 1 - 5 wherein high pressure, low density polyethylene homopolymer or copolymer is present in an amount less than about 50 % by weight.

Claim 9

7) A process as defined in any one of the claims 1 - 3 or 5 wherein said linear low density ethylene hydrocarbon copolymer is a copolymer of ethylene and at least one C 3 - C 8 alpha olefin having a melt index between.about 0.5 and about 100, preferably between about 2 and about 50, especially between about 10 and about 30.

Claim 10

8) A process as defined in any one of the claims 1 - 3 or 5- wherein said linear low density ethylene hydrocarbon copolymer is a copolymer of greater than about 25 mol percent ethylene and less than about 15 mol percent of at least one C 3 - C 8 alpha olefin.

Claim 11

9) A process as defined in any one of the claims 1-2 or 7 wherein said copolymer has a melt flow ratio of about >22 to ≤36 and a total unsaturation content of about ≥ 0.1 to ≤0.3 C=C/1000 C atoms.

Claim 12

10) A process as defined in any one of the claims 1 - 2 or 8 wherein the alpha olefin comprises butene-1.

Claim 13

11) An extrusion coating composition comprising more than 20 and less than 98 weight percent of a high pressure, low density polyethylene homopolymer or copolymer and more than 2 and less than 80 weight percent of a linear, low density ethylene hydrocarbon copolymer.

Claim 14

11) An extrusion coating composition comprising more than 20 and less than 98 weight percent of a high pressure, low density polyethylene homopolymer or copolymer and more than 2 and less than 80 weight percent of a linear, low density ethylene hydrocarbon copolymer.

Claim 15

12) An extrusion coating composition comprised of a blend of (1) a high pressure, low density polyethylene homopolymer or copolymer which, when extruded by itself at coating speeds greater than 183 m (600 ft)/min with a neck-in less than about 7,6 cm (3 inches), will produce a coa ting having pinholes therein at thicknesses of about 0.013 mm (0.5 mils), and (2) a linear, low density ethylene hydrocarbon copolymer, which, when extruded by itself at coating speeds greater than 91 m (300 ft)/min at a thickness of about 0.010 mm (0.4 mils) will exhibit draw resonance, said high pressure, low density polyethy lene homopolymer or copolymer being present in an amount greater than about 20-and less than about 98 weight percent, preferably between about 30 and 90 weight percent, said linear, low density ethylene hydrocarbon copolymer being present in an amount greater than about 2 and less than about 80 weight percent, preferably between 10 and 70 weight percent, said blend when extruded at a coating speed greater than 183 m (600 ft)/min with a neck-in less than about 7.6 cm (3 inches) will produce a coating free of pinholes at a thickness of about 0.013 mm (0.5 mils) in the absence of draw resonance.

Claim 16

12) An extrusion coating composition comprised of a blend of (1) a high pressure, low density polyethylene homopolymer or copolymer which, when extruded by itself at coating speeds greater than 183 m (600 ft)/min with a neck-in less than about 7,6 cm (3 inches), will produce a coa ting having pinholes therein at thicknesses of about 0.013 mm (0.5 mils), and (2) a linear, low density ethylene hydrocarbon copolymer, which, when extruded by itself at coating speeds greater than 91 m (300 ft)/min at a thickness of about 0.010 mm (0.4 mils) will exhibit draw resonance, said high pressure, low density polyethy lene homopolymer or copolymer being present in an amount greater than about 20-and less than about 98 weight percent, preferably between about 30 and 90 weight percent, said linear, low density ethylene hydrocarbon copolymer being present in an amount greater than about 2 and less than about 80 weight percent, preferably between 10 and 70 weight percent, said blend when extruded at a coating speed greater than 183 m (600 ft)/min with a neck-in less than about 7.6 cm (3 inches) will produce a coating free of pinholes at a thickness of about 0.013 mm (0.5 mils) in the absence of draw resonance.

Claim 17

13) A composition as defined in claims 11 or 12 wherein said high pressure, low density polyethylene homopolymer or copolymer has a melt index between about 1 and about 20, preferably between about 2 and about 6.

Claim 18

14) A composition as defined in claims 11 or 12 wherein said high pressure, low density polyethylene copolymer is a copolymer of ethylene ethyl acrylate and ethylene vinyl acetate having a melt index between about 2 and about 6.

Claim 19

15) A composition as defined in any one of the claims 11 - 14 wherein the high pressure, low density polyethylene homopolymer or copolymer is present in an amount between about 40 and 80 weight percent, and said linear low d en- sity ethylene hydrocarbon copolymer is present in an amount between about 20 and 60 weight percent.

Claim 20

16) A composition as defined in any one of the claims 11 - 15 wherein high pressure, low density polyethylene homopolymer or copolymer is present in an amount less than about 50 % by weight.

Claim 21

17) A composition as defined in any one of the claims 11 - 13 or 15 wherein said linear low density ethylene hydrocarbon copolymer is a copolymer of ethylene and at least one C 3 -C 8 alpha olefin having a melt index between about 0.5 and about 100, preferably between about 2 and about 100, especially between about 10 and about 30.

Claim 22

18) A composition as defined in any one of the claims 11 - 13 or 15 - 17 wherein said linear low density ethylene hydrocarbon copolymer is a copolymer of greater than about 25 mol percent ethylene and less than about 15 mol percent of at least one C 3 -C 8 alpha olefin.

Claim 23

19) A composition as defined in any one of the claims 11 - 12 or 17 wherein said copolymer has a melt flow ratio of about ≥22 to ≤36 and a total unsaturation content of about-0.1 to ≤0.3 C=C/1000 C atoms.

Claim 24

20) A composition as defined in any one of the claims 11-12 or 18 wherein the alpha olefin comprises.butene-1.

Claim 25

21) A coated article wherein the coating comprises a blend of more than 20 and less-than 98 weight percent of high pressure, low density polyethylene homopolymer and/or copolymer and more than 2 and less than 80 weight percent of at least one linear, low density ethylene hydrocarbon copolymer.

Claim 26

21) A coated article wherein the coating comprises a blend of more than 20 and less-than 98 weight percent of high pressure, low density polyethylene homopolymer and/or copolymer and more than 2 and less than 80 weight percent of at least one linear, low density ethylene hydrocarbon copolymer.