Mutilayer polyethylene films, and articles made therefrom

Patent metadata

Field	Value
Publication number	US-10857703-B2
Application number	US-201615766394-A
Country	US
Kind code	B2
Filing date	Nov 8, 2016
Priority date	Dec 11, 2015
Publication date	Dec 8, 2020
Grant date	Dec 8, 2020

Abstract

A multilayer polyethylene film comprising a core layer, a first outer layer, and a second outer layer, wherein the core layer is positioned between the first outer layer and the second outer layer, the core layer comprises a linear low density polyethylene and, optionally, a first low density polyethylene resin, and the first outer layer and the second outer layer independently comprise a polyethylene resin and, optionally, a second low density polyethylene resin, wherein the density of the linear low density polyethylene is less than the density of the polyethylene resin.

First claim

The invention claimed is:

1. A multilayer polyethylene film comprising a core layer, a first outer layer, and a second outer layer, wherein:
the core layer is positioned between the first outer layer and the second outer layer;
the core layer comprises a linear low density polyethylene having a density of 0.900 g/cc to 0.935 g/cc and a melt index, I 2 , of 0.1 g/10 min to 10 g/10 min, and, optionally, a first low density polyethylene resin having a density from 0.915 g/cc to 0.935 g/cc and a melt index, I 2 , from 0.1 g/10 min to 15 g/10min; and
the first outer layer and the second outer layer independently comprise a polyethylene resin having a density of 0.935 g/cc to 0.970 g/cc and a melt index, I 2 , of 0.1 g/10 min to 15 g/10 min and, optionally, a second low density polyethylene resin having a density from 0.915 g/cc to 0.935 g/cc and a melt index, I 2 , from 0.1 g/10 min to 15 g/10 min;
wherein the density of the linear low density polyethylene is less than the density of the polyethylene resin,
wherein the first outer layer comprises from 5 wt. % to 40 wt. % of the second low density polyethylene resin, based on the total weight of polymers present in the first outer layer.

2. The film of claim 1 , wherein the core layer comprises from 5 wt. % to 40 wt. % of the first low density polyethylene resin, based on the total weight of polymers present in the core layer.

3. The film of claim 1 , wherein the second outer layer comprises from 5 wt. % to 40 wt. % of the second low density polyethylene resin, based on the total weight of polymers present in the second outer layer.

4. The film of claim 1 , wherein the ratio of the core layer to the first and second outer layers ranges from 50:50 to 90:10.

5. The film of claim 1 , wherein the first outer layer has the same thickness as the second outer layer.

6. The film of claim 1 , wherein the first outer layer has the same composition as the second outer layer.

7. A method of manufacturing the multilayer polyethylene film of claim 1 , wherein the method comprises:
coextruding a core layer, first outer layer, and a second outer layer to form a multilayer polyethylene film, wherein the multilayer polyethylene film comprises:
the core layer positioned between the first outer layer and the second outer layer;
the core layer comprising a linear low density polyethylene having a density of 0.900 g/cc to 0.935 g/cc and a melt index, I 2 , of 0.1 g/10 min to 10 g/10 min, and, optionally, a first low density polyethylene resin having a density from 0.915 g/cc to 0.935 g/cc and a melt index, I 2 , from 0.1 g/10 min to 15 g/10 min; and
the first outer layer and the second outer layer independently comprising a polyethylene resin having a density of 0.930 g/cc to 0.970 g/cc and a melt index, I 2 , of 0.1 g/10 min to 15 g/10 min and, optionally, a second low density polyethylene resin having a density from 0.915 g/cc to 0.935 g/cc and a melt index, I 2 , from 0.1 g/10 min to 15 g/10 min;
wherein the density of the linear low density polyethylene is less than the density of the polyethylene resin.
Wherein the first outer layer comprises from 5 wt. % to 40 wt. % of the second low density polyethylene resin, based on the total weight of polymers present in the first outer layer.

8. An ultrasonically-bonded laminate comprising:
the multilayer polyethylene film of claim 1 ; and
a nonwoven substrate at least partially ultrasonically bonded to the multilayer film to form a laminate.

9. The laminate of claim 8 , wherein the nonwoven substrate is formed from a polypropylene resin.

Assignees

• Dow Global Technologies Llc
• Dow Quim Mexicana S A De C V

Inventors

• Kalihari Vivek
• Arteaga Larios Fabricio
• Degroot Jacquelyn A

Classifications

• B32B2262/0253

  Polyolefin fibres · CPC title

• B29L2009/00

  Layered products · CPC title

• B29L2007/008

  Wide strips, e.g. films, webs · CPC title

• B29K2995/0063

  Density · CPC title

• B29K2023/0625

  LLDPE, i.e. linear low density polyethylene · CPC title