Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
  • B32B27/28—Layered products comprising a layer of synthetic resin comprising synthetic resins not wholly covered by any one of the sub-groups B32B27/30 - B32B27/42
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B15/00—Layered products comprising a layer of metal
  • B32B15/04—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material
  • B32B15/08—Layered products comprising a layer of metal comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin

Definitions

• This invention relates to metal-polymer laminates useful for fabricating articles, such as beverage containers and aerosol containers.
• Metal-polymer laminates are known and are described, for example, in U.S. Patents 4,626,157; 4,423,823; 4,034,132; 4,686,152; 4,734,303 and 4,361 ,020.
• the polymers employed in preparing the laminates include polyesters, polypropylene, polyethylene, polycarbonate, polyimide and blends thereof. Films prepared from these polymers suffer from their inadequate adhesion to the metal, their inability to elongate during metal forming due to the highly oriented nature of the polymer film, and their tendency to delaminate during forming and/or end-use application.
• Thin polyolefin-based films with polar comonomer adhesive layers while offering good adhesion characteristics to metal, and good elongation during metal laminate forming, can suffer from inadequate laminate cuttability (resulting in coating "stringing"), and inadequate scratch resistance and end-use toughness.
• the present invention is a container comprising a laminate structure having one or more layers of a metal and one or more layers of a hydroxy- functional polyether (hydroxy-functional polyether) and, optionally, one or more layers of an organic polymer which is not hydroxy-functional polyether.
• hydroxy-functional polyetherhydroxy-functional polyethers employed in the practice of the present invention for preparing the polymer layer(s) are:
• the monolayer film will have a thickness of from 0.1 to 10.0 mils, preferably from 0.2 to 5.0 mils and most preferably, 0.4 to 1.0 mils.
• the multilayer film will have a total thickness of from 0.1 to 10.0 mils, preferably from 0.2 to 5.0 mils; with the thickness of the hydroxy-functional polyether layer(s) being from 10 percent to 90 percent, and preferably 20 percent to 80 percent of the total film thickness.
• the metals which can be employed in the practice of the present invention for preparing the polymer-metal or polymer-metal-polymer laminate include tin plate steel (TPS), tin-free steel (TFS), electrochrome-coated steel (ECCS), galvanized steel, high strength low alloy steel, stainless steel, copper-plated steel, copper and aluminum.
• the preferred metals are tin plate steel and tin-free steel.
• the metal is in the form of a flat sheet having two major surfaces.
• the metal typically ranges from 3 to 20 mils in thickness, although the hydroxy-functional polyether film can be adhered to any gauge metal. It is within the scope of this present invention to laminate the hydroxy- functional polyether film to thin metal foil such as 0.2 to 2 mil aluminum foil used in flexible packaging.
• the polymer-metal or polymer-metal-polymer laminates of the present invention can be prepared by conventional lamination techniques.
• specific laminating techniques include thermal lamination, that is, whereby an inherently melt activated adhesive film is heated and melt-bonded to a metal substrate by means of heat and pressure; or liquid coating and laminating, that is, whereby a separate adhesive such as a solvent-borne or aqueous-based adhesive is applied to the polymeric film or metal substrate at a desired thickness, the liquid driven off by a drying oven, and combining the film and the metal with heat and pressure to bond the two layers together.
• thermal lamination that is, whereby an inherently melt activated adhesive film is heated and melt-bonded to a metal substrate by means of heat and pressure
• liquid coating and laminating that is, whereby a separate adhesive such as a solvent-borne or aqueous-based adhesive is applied to the polymeric film or metal substrate at a desired thickness, the liquid driven off by a drying oven, and combining the film and the metal with heat and pressure to bond the two layers together.
• a hot-melt adhesive can be melted and applied by means of slot die coating or roll coating onto either the film or the metal and joining the two plies of film and metal together with pressure using the molten hot-melt adhesive to intimately bond the structure together, followed by cooling.
• a two-ply laminate comprising a polymer film layer and a metal layer can be prepared in accordance with the present invention by contacting one of the major surfaces of the metal layer with the polymer film at an elevated temperature with concurrent application of pressure.
• a three-ply laminate comprising a polymer film layer, a metal layer and a polymer film layer is formed by applying to the remaining major surface of the metal layer another polymer film layer which is the same as or different from the other polymer film layer.
• the polymer-metal or polymer-metal-polymer laminates can have any one of the following structures:
• a three-ply laminate comprising a first outer layer of a co-extruded hydroxy-functional polyether/PETG film, a core layer of a metal and a second outer layer of an organic polymer which is not a hydroxy-functional polyether.
• the organic polymer which is not a hydroxy-functional polyether can be a blend of two or more different organic polymers.
• a two-layer coextruded 0.6 mil film was produced from a glycol-modified copolyester (PETG), available from Eastman Chemical Company as PETG 6763 resin and a phenoxy resin (PaPhen PKFE).
• PETG resin was extruded at a melt temperature of 225°C in one layer, while the phenoxy resin was extruded at 225°C in a second adjacent layer.
• the 0.6 mil film comprises a 60 percent PETG layer and 40 percent phenoxy layer, based on the film thickness.
• the coextruded two-layer film was quenched on a chill roll at 65°C, further cooled to 30°C, and wound into a film roll.
• a monolayer film of a poly(hydroxy amino ether) (PHAE) resin was made on a conventional cast film line.
• the PHAE resin was produced from the reaction of the diglycidyl ether of bisphenol A (DGEBA) and monoethanolamine (MEA) following the procedure described in U.S. Patent 5,275,853, and had a T g of 70°C and a molecular weight of 60,000.
• DGEBA diglycidyl ether of bisphenol A
• MEA monoethanolamine
• the film was thermally laminated to a 10.5 mil tin plate steel, a 6 mil aluminum and a 6 mil ECCS at a temperature of 204°C. In all three cases, the PHAE film exhibits excellent adhesion to metal and could not be peeled from the metal.
• a 0.6 mil biaxially oriented polyester (OPET) film was coated with a solvent-based phenoxy solution (40 percent phenoxy solids in methyl-ethyl ketone, available from Phenoxy Associates as UCAR PKHS-40).
• a conventional liquid coater was used to apply the wet liquid coating to one side of the OPET film.
• the wet-coated film was then transported through a multizone hot air impingement drying oven (zone temperatures: 90°F to 150°F, 32°C to 65°C) to dry off the solvent, leaving a 0.2 mil solid phenoxy layer on the 0.6 mil OPET film.
• the 0.8 mil coated OPET film was then wound into a roll.
• the film was later thermally laminated onto pre-heated tin plate steel at 204°C using a coil metal lamination line, with the phenoxy layer adhered to the metal surface.
• the hot laminate was then quenched to room temperature using forced-air cooling and water-cooled chill rolls.
• the metal laminates of Examples 1 , 2, 3, 4, 5 and 6 were drawn and formed into a 33 mm diameter by 12 mm deep cup using a Tinius Olsen Ductomatic BUP 200 metal forming press. Cups with the laminate thin film on the outside of the cup and with the laminate thin film on the inside of the cup were produced. The thin films exhibitedexcellent adhesion to the formed metal with no film delamination observed.
• Multilayered metal laminates using the same phenoxy-based films of Examples 1 ,2,3 and 4 were produced with a coextruded 7.2 mil polypropylene (PP)-ultra linear low density polyethylene (ULLDPE) blend film simultaneously laminated onto the opposite side of the metal from the phenoxy-based film.
• the polypropylene film was a two-layer coextrusion with a 50 percent PP and 50 percent ULLDPE main layer (85 percent of film gauge) and a maleic anhydride grafted polyethylene adhesive layer (15 percent of film gauge), which was made in accordance with the teachings of U.S. Patent 5, 006,383.
• the 7.2 mil PP film was laminated to the top side of a preheated 10.5 mil tin plate steel and the respective Example 1 , 2, 3 or 4 phenoxy-based film of 0.5 to 0.8 mil gauge was laminated to the bottom side of the steel.
• Thermal lamination was conducted at 204°C on a continuous coil steel lamination coating process. After lamination, the two-sided coated steel was cooled, wound into a roll, and later slit to desired widths. The slit narrow web coils were later stamped into intricately shaped 25 mm diameter aerosol valve mounting cups (AVMC) using a commercial continuous 14-station multidie press.
• AVMC aerosol valve mounting cups
• Each of the laminated structures exhibited good formability and drawability and no signs of film delamination.
• the aerosol valve mounting cups were then further converted into aerosol valve assemblies by the addition of a valve, actuator and stem assembly using a commercial valve assembly operation.

Landscapes

• Laminated Bodies (AREA)
• Containers And Packaging Bodies Having A Special Means To Remove Contents (AREA)
• Wrappers (AREA)

Priority Applications (7)

Applications Claiming Priority (2)

Publications (1)

Family

ID=25540388

Family Applications (1)

Country Status (11)

Cited By (5)

Families Citing this family (2)

Citations (5)

• 1998
  • 1998-10-23 BR BR9813782-4A patent/BR9813782A/pt not_active IP Right Cessation
  • 1998-10-23 WO PCT/US1998/022430 patent/WO1999032281A1/en not_active Application Discontinuation
  • 1998-10-23 EP EP98967110A patent/EP1040000A1/en not_active Withdrawn
  • 1998-10-23 CN CN98812429A patent/CN1282292A/zh active Pending
  • 1998-10-23 JP JP2000525247A patent/JP2001526130A/ja active Pending
  • 1998-10-23 KR KR1020007006720A patent/KR20010033280A/ko not_active Application Discontinuation
  • 1998-10-23 NZ NZ504927A patent/NZ504927A/en unknown
  • 1998-10-23 CA CA002314243A patent/CA2314243A1/en not_active Abandoned
  • 1998-10-23 AU AU39096/99A patent/AU747013B2/en not_active Ceased
  • 1998-11-12 ID IDP981482A patent/ID22593A/id unknown
  • 1998-12-18 ZA ZA9811646A patent/ZA9811646B/xx unknown

Patent Citations (5)

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events