Pouches of ethylene/octene-1 copolymer film containing a flowable material

• US 4,521,437 A
• Filed: 06/02/1983
• Issued: 06/04/1985
• Est. Priority Date: 06/02/1982
• Status: Expired due to Term

• Current Assignee: Du Pont Taiwan Limited (Corteva, Inc.)
• Original Assignee: Du Pont Taiwan Limited (Corteva, Inc.)
• Inventors: Storms, William J.
• Primary Examiner(s): SLUBY, PATRICIA
• Application Number:
  US06/500,386
• Time in Patent Office: 733 Days
• Field of Search: 428/516, 428/35, 428/192, 428/518, 428/323, 428/328, 428/408, 426/130
• US Class Current: 426/130
• CPC Class Codes: B32B 1/08 Tubular products
• CPC Class Codes: B32B 2307/31 Heat sealable
• CPC Class Codes: B32B 2307/4026 within the layer by addition of a colorant, e.g. pigments, dyes
• CPC Class Codes: B32B 2439/00 Containers; Receptacles
• CPC Class Codes: B32B 27/08 of synthetic resin
• CPC Class Codes: B32B 27/20 using fillers, pigments, thixotroping agents
• CPC Class Codes: B32B 27/304 comprising vinyl halide (co)polymers, e.g. PVC, PVDC, PVF, PVDF
• CPC Class Codes: B32B 27/32 comprising polyolefins comprising vinyl (co)polymers or acrylic (co)polymers B32B27/30
• CPC Class Codes: B32B 27/36 comprising polyesters
• CPC Class Codes: C08J 2323/08 Copolymers of ethene C08J2323/16 takes precedence
• CPC Class Codes: C08J 5/18 Manufacture of films or sheets
• CPC Class Codes: C08L 2205/02 containing two or more polymers of the same C08L -group
• CPC Class Codes: C08L 2205/03 containing three or more polymers in a blend
• CPC Class Codes: C08L 23/06 Polyethene
• CPC Class Codes: C08L 23/0815 Copolymers of ethene with aliphatic 1-olefins
• CPC Class Codes: C08L 23/0853 Vinylacetate
• CPC Class Codes: C08L 2666/02 Organic macromolecular compounds, natural resins, waxes or and bituminous materials
• CPC Class Codes: C08L 2666/06 Homopolymers or copolymers of unsaturated hydrocarbons; Derivatives thereof
• CPC Class Codes: Y10T 156/1005 by inward collapsing of portion of hollow body
• CPC Class Codes: Y10T 428/1334 Nonself-supporting tubular film or bag [e.g., pouch, envelope, packet, etc.]
• CPC Class Codes: Y10T 428/1345 : Single layer [continuous layer]
• CPC Class Codes: Y10T 428/24777 : Edge feature
• CPC Class Codes: Y10T 428/25 : Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles
• CPC Class Codes: Y10T 428/256 : Heavy metal or aluminum or compound thereof
• CPC Class Codes: Y10T 428/2817 : Heat sealable
• CPC Class Codes: Y10T 428/30 : Self-sustaining carbon mass or layer with impregnant or other layer
• CPC Class Codes: Y10T 428/31913 : Monoolefin polymer
• CPC Class Codes: Y10T 428/3192 : Next to vinyl or vinylidene chloride polymer

Abstract

Pouches containing a flowable material e.g. milk, ice cream, are made of a sealant film which is from about 50 to 100 parts by weight of a linear copolymer of ethylene and a C₆ -C₁₀ α-olefin, and from 0 to 50 parts by weight of at least one polymer selected from linear copolymer of ethylene and a C₄ -C₁₀ α-olefin, and a high-pressure polyethylene. The sealant film is selected on the basis of providing (a) pouches with an M-test value substantially better, at the same film thickness, than that obtained with pouches made with film of a specified blend of an ethylene-butene copolymer and a high pressure polyethylene, or (b) an M(2)-test value of less than about 12%, for pouches having a volume of from greater than 1.3 to 5 liters, or (c) an M(1.3)-test value of less than about 5% for pouches having a volume of from 0.1 to 1.3 liters. The M, M(2) and M(1.3)-tests are defined pouch drop tests. The pouches may also be made from composite films in which the sealant film forms at least the inner layer.

Claims

1. A pouch containing a flowable material, said pouch being made from a sealant film in tubular form and having transversely heat-sealed ends, said sealant film being made from a material comprising about 50 to 100 parts of a linear copolymer of ethylene and an octene-1 having a density of from 0.916 to 0.930 g/cm³ and a melt index of 0.3 to 2.0 dg/min, and from 0 to 50 parts by weight of at least one polymer selected from the group consisting of a linear copolymer, of ethylene and a C₄ -C₁₀ α

-olefin having a density of from 0.916 to 0.930 g/cm³ and a melt index of from 0.3 to 2.0 dg/min, and a high-pressure polyethylene having a density of from 0.916 to 0.924 g/cm³ and a melt index of from about 1 to 10 dg/min, said sealant film being selected on the basis of providing (a) pouches with an M-test value substantially smaller at the same film thickness, than that of pouches made with film of a blend of 85 parts of a linear ethylene/butene-1 copolymer having a density of about 0.919 g/cm³ and a melt index of about 0.75 dg/min and 15 parts of a high pressure polyethylene having a density of about 0.918 g/cm³ and a melt index of 8.5 dg/min, or (b) an M(2)-test value of less than about 12%, for pouches having a volume of from greater than 1.3 to 5 liters, or (c) M(1.3)-test value of less than about 5% for pouches having a volume of from 0.1 to 1.3 liters.

2. A pouch according to claim 1 wherein the M-test value for said pouch is at least 30% less than that for pouches made from film of said blend of ethylene-butene copolymer and high pressure polyethylene.

3. A pouch according to claim 1 in which the sealant film is made from a blend of from 60 to 100 parts by weight of an ethylene-octene copolymer and from 0 to 40 parts by weight of a high-pressure polyethylene.

4. A pouch, according to claim 1 having a volume of from greater than 1.3 liters to 5 liters wherein the M(2)-test value is less than 6%.

5. A pouch according to claim 1 wherein the flowable material is a liquid or an emulsion.

6. A pouch according to claim 2 wherein the sealant film is made using a blown film process in which process the blown film is cooled by passing the film in close proximity to a cooled metal mandrel.

7. A pouch according to claim 2 wherein the sealant film contains a pigment.

8. A pouch according to claim 2 wherein the sealant film forms a part of a composite film, said sealant film being at least on the inside of the pouch.

9. A pouch containing a flowable material, said pouch being made from a composite film in tubular form and having transversely heat-sealed ends, said composite film containing at least one layer of a sealant film, at least one layer of the sealant film being made from a material comprising about 50 to 100 parts of a linear copolymer of ethylene and octene-1 having a density of from 0.916 to 0.930 g/cm³ and a melt index of 0.3 to 2.0 dg/min, and from 0 to 50 parts by weight of at least one polymer selected from the group consisting of a linear copolymer, of ethylene and a C₄ -C₁₀ α

-olefin having a density of from 0.916 to 0.930 g/cm³ and a melt index of from 0.3 to 2.0 dg/min, and a high-pressure polyethylene having a density of from 0.916 to 0.924 g/cm³ and a melt index of from about 1 to 10 dg/min, said sealant film being selected on the basis of providing (a) pouches made from said sealant film with an M-test value substantially smaller at the same film thickness, than that of pouches made with film of a blend of 85 parts of a linear ethylene-butene-1 copolymer having a density of about 0.919 g/cm³ and a melt index of about 0.75 dg/min and 15 parts of a high pressure polyethylene having a density of about 0.918 g/cm³ and a melt index of 8.5 dg/min, or (b) an M(2)-test value of less than about 12%, for pouches having a volume of from greater than 1.3 to 5 liters, or (c) M(1.3)-test value of less than about 5% for pouches having a volume of from 0.1 to 1.3 liters.

10. A pouch according to claim 9 wherein the sealant film is selected upon the basis of the M-test value being at least 30% less than that for pouches made from film of said blend of ethylene-butene copolymer and high pressure polyethylene.

11. A pouch according to claim 9 wherein the flowable material is milk and the composite film comprises at least one layer of sealant film containing a dark pigment and at least one layer of sealant film containing a light pigment.

12. A pouch according to claim 9 wherein the flowable material is milk and the composite film comprises at least one layer of sealant film containing a pigment selected from carbon black, iron oxide, aluminium and bronze, and at least one layer of sealant film containing a pigment selected from titanium dioxide and zinc oxide.

13. A pouch according to claim 9 wherein the composite film comprises at least one layer of said sealant film and a layer selected from nylon film, polyester film, ethylene/vinyl alcohol copolymer film and polyvinylidene chloride film.