Polyethylene multilayer substrates, printing substrates, laminates, and packaging materials

Abstract

To provide a polyethylene multilayer substrate having excellent heat resistance.SOLUTION: A polyethylene multilayer substrate has been drawn and comprises a first polyethylene layer, a second polyethylene layer, and a third polyethylene layer in the stated order in a thickness direction, where the first polyethylene layer has an indentation elastic modulus that is 3.0 or more times higher than that of the second polyethylene layer, and the third polyethylene layer has an indentation elastic modulus that is 3.0 or more times higher than that of the second polyethylene layer.SELECTED DRAWING: Figure 1

Claims

1. A first polyethylene layer containing at least medium-density polyethylene and / or high-density polyethylene, A polyethylene layer 2a containing at least linear low-density polyethylene, A second polyethylene layer containing at least linear low-density polyethylene, A second polyethylene layer b containing at least linear low-density polyethylene, A third polyethylene layer containing at least medium-density polyethylene and / or high-density polyethylene A polyethylene multilayer substrate with five layers arranged in this order in the thickness direction, Of the five polyethylene layers, at least one layer is composed of a blend of at least two types of polyethylene with different densities. In the first polyethylene layer, the mass ratio of medium-density polyethylene to high-density polyethylene (medium-density polyethylene / high-density polyethylene) is 1.1 or more and 5 or less. In the third polyethylene layer, the mass ratio of medium-density polyethylene to high-density polyethylene (medium-density polyethylene / high-density polyethylene) is 1.1 or more and 5 or less. The total content of medium-density polyethylene and high-density polyethylene in the first polyethylene layer is 80% by mass or more. The total content of medium-density polyethylene and high-density polyethylene in the third polyethylene layer is 80% by mass or more. The content of linear low-density polyethylene in the second polyethylene layer is more than 50% by mass. The indentation modulus of the first polyethylene layer is 3.0 times or more than that of the second polyethylene layer, and the indentation modulus of the third polyethylene layer is 3.0 times or more than that of the second polyethylene layer. The polyethylene multilayer substrate is obtained by stretching the longitudinal (MD) and / or transverse (TD) directions at a stretching ratio of 2 to 10 times, respectively. Polyethylene multilayer substrate.

2. The indentation modulus of the polyethylene layer 2a is 2.0 times or more than that of the second polyethylene layer, and the indentation modulus of the polyethylene layer 2b is 2.0 times or more than that of the second polyethylene layer. The polyethylene multilayer substrate according to claim 1.

3. The polyethylene multilayer substrate according to claim 1 or 2, wherein the indentation modulus of the first polyethylene layer and the third polyethylene layer are each independently 1.1 GPa or more and 6.0 GPa or less.

4. The first polyethylene layer is a surface layer on one side of the polyethylene multilayer substrate. The third polyethylene layer is the other surface layer of the polyethylene multilayer substrate. A polyethylene multilayer substrate according to any one of claims 1 to 3.

5. A polyethylene multilayer substrate according to any one of claims 1 to 4, A printed layer formed on the polyethylene multilayer substrate and A printing substrate equipped with the following features.

6. Polyethylene multilayer substrate and A heat seal layer containing polyethylene as the main component and A laminate comprising, The polyethylene multilayer substrate is A first polyethylene layer containing at least medium-density polyethylene and / or high-density polyethylene, A polyethylene layer 2a containing at least linear low-density polyethylene, A second polyethylene layer containing at least linear low-density polyethylene, A second polyethylene layer b containing at least linear low-density polyethylene, A third polyethylene layer containing at least medium-density polyethylene and / or high-density polyethylene It has a five-layer structure with these layers arranged in this order in the thickness direction. Of the five polyethylene layers, at least one layer is composed of a blend of at least two types of polyethylene with different densities. In the first polyethylene layer, the mass ratio of medium-density polyethylene to high-density polyethylene (medium-density polyethylene / high-density polyethylene) is 1.1 or more and 5 or less. In the third polyethylene layer, the mass ratio of medium-density polyethylene to high-density polyethylene (medium-density polyethylene / high-density polyethylene) is 1.1 or more and 5 or less. The total content of medium-density polyethylene and high-density polyethylene in the first polyethylene layer is 80% by mass or more. The total content of medium-density polyethylene and high-density polyethylene in the third polyethylene layer is 80% by mass or more. The content of linear low-density polyethylene in the second polyethylene layer is more than 50% by mass. The polyethylene multilayer substrate is stretched to a ratio of 2 to 10 times in the longitudinal direction (MD) and / or transverse direction (TD), respectively. The indentation modulus of the first polyethylene layer is 3.5 times or more than that of the second polyethylene layer, and the indentation modulus of the third polyethylene layer is 3.5 times or more than that of the second polyethylene layer. Laminated structure.

7. The indentation modulus of the polyethylene layer 2a is 2.0 times or more than that of the second polyethylene layer, and the indentation modulus of the polyethylene layer 2b is 2.0 times or more than that of the second polyethylene layer. The laminate according to claim 6.

8. The laminate according to claim 6 or 7, further comprising a printed layer on the polyethylene multilayer substrate.

9. The laminate according to any one of claims 6 to 8, further comprising a barrier layer formed on the surface of the polyethylene multilayer substrate or on the surface of the heat seal layer.

10. The laminate according to any one of claims 6 to 9, further comprising an adhesive layer between the polyethylene multilayer substrate and the heat seal layer.

11. A packaging material comprising a polyethylene multilayer substrate according to any one of claims 1 to 4, a printing substrate according to claim 5, or a laminate according to any one of claims 6 to 10.

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