Polyolefin resin composition for metal coating, and resin film and resin-coated metal material using the same

1. A resin-coated metal material comprising a metal material at least partially coated with a sheet of a polyolefin resin composition, wherein said polyolefin resin composition comprises:

components (A), (B), (C), and (D)

wherein

(A) is a polyolefin resin,

(B) is an organified layered inorganic material,

(C) is an olefin-containing oligomer having a repeating unit of —CR 1 H—CR 2 R 3 —,

wherein R 1 and R 2 each independently represents an alkyl group having a carbon number of 1 to 12 or hydrogen, and R 3 represents an alkyl group having a carbon number of 1 to 12, an aryl group or hydrogen, wherein said olefin-containing oligomer (C) contains a functional group having polarity in which elements differing in electronegativity by 0.39 (eV) 0.5 or more are bonded to the olefin-containing oligomer, and said olefin-containing oligomer (C) has a molecular weight of 1000 to 500,000,

(D) is a rubber-like elastic material having a repeating unit of —CR 1 H—CR 2 R 3 —,

wherein R 1 and R 2 each independently represents an alkyl group having a carbon number of 1 to 12 or hydrogen, and R 3 represents an alkyl group having a carbon number of 1 to 12, an aryl group or hydrogen, wherein the rubber-like elastic material has a Young's modulus of 10 −1 to 10 3 MPa,

wherein said layered inorganic material (B) and said rubber-like elastic material (D) are dispersed in said polyolefin resin (A),

wherein a dispersion diameter of the layered inorganic material (B) is from 50 to 300 nm, and an aspect ratio of a long side to a thickness of one crystalline inorganic material layer is from 100 to 500,

wherein a long diameter of said rubber-like elastic material (D) is 3 μm or less, the ratio between the long axis and the short axis of the dispersion diameter of the rubber-like elastic material (D) is from 1 to 20, the ratio (MFR(A)/MFR(D)) between a melt flow index (MFR(A)) of said polyolefin resin (A) and a melt flow index (MFR(D)) of said rubber-like elastic material (D) is from 0.1 to 10,

wherein a dispersion diameter of the olefin-containing oligomer (C) is from 1 to 100 nm and the ratio between the long axis and the short axis of the dispersion diameter of the olefin-containing oligomer (C) is 2 or less,

wherein a thickness of the resin sheet is from 0.5 μm to 50 mm, and the layered inorganic material (B) is oriented in the direction parallel to a sheet plane, and

wherein said resin composition has a formulation such that the polyolefin resin (A) is 20 mass % or more based upon the total mass of the resin composition, the layered inorganic material (B) is from 0.01 to 30 mass % based upon the total mass of the resin composition, the olefin-containing oligomer (C) containing a functional group having polarity is from 3 to 60 mass % based upon the total mass of the resin composition, and the rubber-like elastic material (D) is from 1 to 30 mass % based upon the total mass of the resin composition.

2. The resin-coated metal material according to claim 1 , wherein said metal material is a metal sheet.

3. The resin-coated metal material according to claim 1 , wherein said rubber-like elastic material (D) is an olefin-containing rubber-like elastic material.

4. The resin-coated metal material according to claim 1 , wherein said layered inorganic material (B) is a clay mineral.

5. The resin-coated metal material according to claim 4 , wherein said clay mineral is montmorillonite.

6. The resin-coated metal material according to claim 1 , wherein the functional group having polarity in component (C) is an acid anhydride, a hydroxyl, a carboxyl, an amide, an amino, a urethane, an ester, an imide, a maleimide, a halogen, an ether, a thiol group or an epoxy.

7. The resin-coated metal material according to claim 1 , wherein the organified layered inorganic material (B) comprising replacing a cation or an anion in an interlayer of the inorganic material with an organic cation or an organic anion.

8. The resin-coated metal material according to claim 7 , wherein the organic cation or organic anion is a cation or an anion containing an alkyl group having a carbon number of 2 to 30 or an aryl group.

9. The resin-coated metal material according to claim 1 , wherein the layered inorganic material has an ion-exchange capacity of 50 to 200 milli-equivalent/100 g.

10. The resin-coated metal material according to claim 1 , wherein said metal material is a stainless steel foil.

11. The resin-coated metal material according to claim 10 , wherein said stainless steel foil has a surface which has been subjected to a surface treatment and said resin coating is provided on the surface treatment of said stainless steel foil.

12. The resin-coated metal material according to claim 11 , wherein said surface treatment is a chromate treatment.