Polymeric Wrapper Structure for Recyclable Dead-Fold Packaging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Traditional candy and gum wrappers are not recyclable due to their composite nature, which includes layers such as paper and foil, and they lack sufficient dead fold characteristics, tear resistance, and barrier qualities.
Innovation Solution
A polymeric film structure composed of alternating layers of low and high density polyethylene, ethylene vinyl alcohol, and cyclic olefin copolymer, which can be co-extruded to provide recyclability and maintain dead fold, tear resistance, and barrier properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional composite wrapper structures (paper, polymeric, foil layers) are used, then barrier qualities and dead fold characteristics are improved, but recyclability deteriorates
Solution Approach 1:
The wrapper is segmented into multiple functional layers (outer polyethylene layer, barrier layer, inner polyethylene layer) that can be separated during recycling. Each layer serves a specific function while maintaining compatibility with recycling processes, allowing the wrapper to provide composite-like performance without the不可回收 nature of traditional multi-material laminates.
Solution Approach 2:
The invention changes the material parameters by using polyethylene with specific density ranges (0.910-0.940 g/cm³ for outer layer, 0.940-0.965 g/cm³ for inner layer) and controlling the thickness of each layer. These parameter optimizations enable the wrapper to achieve adequate barrier properties and mechanical strength while remaining recyclable as polyethylene, resolving the contradiction between performance and recyclability.
2Strength
If polyethylene layers with optimized thickness are used, then dead fold characteristics and tear resistance are improved, but material usage increases
Solution Approach 1:
Different regions of the wrapper have different thicknesses and material compositions optimized for their specific functions. The outer polyethylene layer (0.030-0.060 inches) provides tear resistance and structural integrity, the barrier layer (0.005-0.015 inches) provides moisture and oxygen barrier, and the inner polyethylene layer (0.020-0.040 inches) provides sealability and flexibility. This local optimization achieves adequate tear resistance without excessive material usage throughout the entire wrapper.
Solution Approach 2:
The invention uses a composite structure of different polyethylene densities and a barrier layer to achieve enhanced tear resistance and dead fold characteristics. The combination of outer polyethylene layer, barrier layer, and inner polyethylene layer creates a composite material system where each component contributes specific properties, achieving superior overall performance with optimized total thickness compared to single-layer structures.
Data Source
Figure 1
Figure 2
Figure 3A~3B
AI summary
In an embodiment, the invention comprises a wrapper with dead bend characteristics. The wrapper comprises a first polyethylene layer comprising low density polyethylene; a second polyethylene layer affixed to the first layer, wherein the second polyethylene layer comprises high density polyethylene; a first tie layer affixed to the second layer, opposite the first layer; a barrier layer affixed to the tie layer, opposite the second layer; a second tie layer affixed to the barrier layer, opposite the first tie layer; a third polyethylene layer affixed to the second tie layer, opposite the barrier layer, wherein the third polyethylene layer comprises high density polyethylene; and a fourth polyethylene layer affixed to the third polyethylene layer, opposite the second tie layer, wherein the fourth polyethylene layer comprises low density polyethylene. In an embodiment, the tie layers and the barrier layer may be substituted with a cyclic olefin copolymer layer.