# US 11,078,375 B2 · Thermoplastic resin-coated metal sheet, can body and can lid made from the same metal sheet

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 11,078,375 B2
- Document ID: US11078375B2
- Status: Granted
- Kind: B2
- Application number: 14/895,152
- Filed: 2014-06-16
- Published: 2016-04-28
- Granted: 2021-08-03
- Earliest claimed: 2013-06-21
- Assignees: Toyo Seikan Group Holdings, Ltd.
- Applicants: Toyo Seikan Group Holdings, Ltd.
- Inventors: Nobuhiko Nagai; Shuhei Hiromori
- Web page: https://patentgrep.com/patent/US11078375B2

## CPC

- C09D 167/02: Polyesters derived from dicarboxylic acids and dihydroxy compounds (C09D167/06 takes precedence)
- B32B 15/08: of synthetic resin
- B32B 15/09: comprising polyesters
- B65D 1/12: Cans, casks, barrels, or drums
- B65D 1/165: {Cylindrical cans}
- C09D 5/002: {Priming paints (C09D5/08 takes precedence)}
- C09D 5/08: Anti-corrosive paints
- C09D 165/02: Polyphenylenes
- B32B 1/00: Layered products having a non-planar shape
- B32B 7/12: using interposed adhesives or interposed materials with bonding properties
- B32B 15/18: comprising iron or steel {(B32B15/011, B32B15/012 and B32B15/013 take precedence)}
- B32B 15/20: comprising aluminium or copper {(B32B15/016 and B32B15/017 take precedence)}
- B32B 27/18: characterised by the use of special additives
- B32B 2250/40: Symmetrical or sandwich layers, e.g. ABA, ABCBA, ABCCBA
- B32B 2255/06: on metal layer
- B32B 2255/205: Metallic coating
- B32B 2255/26: Polymeric coating
- B32B 2255/28: Multiple coating on one surface
- B32B 2270/00: Resin or rubber layer containing a blend of at least two different polymers
- B32B 2307/54: Yield strength; Tensile strength
- B32B 2307/714: Inert, i.e. inert to chemical degradation, corrosion
- B32B 2307/732: Dimensional properties
- B32B 2435/02: for containers
- B32B 2439/66: Cans, tins
- B65D 65/42: Applications of coated or impregnated materials
- C09D: COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR (cosmetics A61K; processes for applying liquids or other fluent materials to surfaces, in general, B05D; staining wood B27K5/02; glazes or vitreous enamels C03C; natural resins, French polish, drying-oils, driers, turpentine, per se, C09F; polishing compositions other than French polish, ski waxes C09G; adhesives or use of materials as adhesives C09J; materials for sealing or packing joints or covers C09K3/10; materials for stopping leaks C09K3/12; processes for the electrolytic or electrophoretic production of coatings C25D)
- B32B: LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B65D: CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES

## Abstract

A thermoplastic resin-coated metal sheet obtained by coating at least one surface of a metal sheet with a thermoplastic resin via a polyester type primer, wherein the polyester type primer, if it is in the form of a 10 μm-thick dry primer sheet, has a breaking elongation in a range of 9 to 200% at a tension speed of 1000 mm/min. and an MEK extractability in a range of 3 to 40%. Without using a special thermoplastic resin-coated film or surface-treated metal sheet, therefore, the cans and can lids can be formed using the thermoplastic resin-coated metal sheet of the invention maintaining excellent and close adhesion during the working, preventing the can body from breaking and the thermoplastic resin coating from peeling at the flange-forming portion during the working, the cans and can lids excelling in dent resistance and economy.

## Claims

### Claim 1

A seamless can formed from a thermoplastic resin-coated metal sheet obtained by coating at least one surface of a metal sheet with a thermoplastic resin coating via an intervening polyester primer layer comprising a polyester primer, wherein
said polyester primer comprises a polyester resin and a curing agent,
said polyester resin consists of 50 mol % of dicarboxylic acid components and 50 mol % of diol components,
the dicarboxylic acid components consist of sebacic acid, isophthalic acid, and optionally terephthalic acid, where the sebacic acid is contained in an amount of 8 to 16.2 mol %, the isophthalic acid is contained in an amount of 15 to 40 mol %, and the terephthalic acid is contained in an amount of 0 to 18.8 mol % based on the total amount of dicarboxylic acid components and diol components of the polyester resin, and
the diol components consist of cyclohexanedimethanol and at least one of ethylene glycol or propylene glycol, where the cyclohexanedimethanol is contained in an amount of 17.7 to 30 mol % and the ethylene glycol and/or the propylene glycol is contained in an amount of greater than 0 to 30 mol % based on the total amount of dicarboxylic acid components and diol components of the polyester resin,
said curing agent being at least one selected from the group consisting of a phenol resin, an isocyanate compound, and an amino resin, and being contained in an amount of 5 to 15 parts by mass per 100 parts by mass of said polyester resin,
said polyester primer layer has a thickness in a range of 0.4 to 2.7 μm,
said polyester primer, when prepared for testing in the form of a 10 μm thick dry primer sheet, has a breaking elongation in a range of 10 to 50% at a tension speed of 1,000 mm/min and an MEK extractability in a range of 9 to 27%,
said thermoplastic resin coating comprises a polyester film and has a thickness in a range of 5 to 40 μm, and
said thermoplastic resin coating is formed in two layers including a lower layer and an upper layer, the lower layer comprises a polyester resin based on an ethylene terephthalate unit containing 1 to 30 mol % of at least one of isophthalic acid or naphthalenedicarboxylic acid, and the upper layer comprises a polyester resin based on an ethylene terephthalate unit containing isophthalic acid or naphthalenedicarboxylic acid in an amount smaller than the amount of the isophthalic acid or the naphthalene dicarboxylic acid contained in the lower layer.

### Claim 2 (depends on 1)

The seamless can formed from a thermoplastic resin-coated metal sheet according to claim 1, wherein said curing agent is the phenolic resin.

### Claim 3 (depends on 1)

The seamless can formed from a thermoplastic resin-coated metal sheet according to claim 1, wherein said curing agent is a resol type phenolic resin derived from an m-cresol.

### Claim 4 (depends on 1)

The seamless can formed from a thermoplastic resin-coated metal sheet according to claim 1, wherein the polyester resin of the polyester primer is polymerized using titanium tetrabutoxide as a polymerization catalyst.