Multilayer A-PET Container with Functional Resin for Heat Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional food containers fail to simultaneously achieve high heat resistance, transparency, and durability, particularly in maintaining food quality across various temperature ranges and resisting dropping impacts.
Innovation Solution
A multilayer container is developed using a process involving primary and secondary stretching and heat-setting of an amorphous polyethylene terephthalate (A-PET) sheet, combined with a functional resin layer, to enhance crystallinity and include an oxygen barrier and dropping resistance layer, ensuring high heat resistance, transparency, and food quality preservation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If A-PET or OPS sheets are used, then high transparency is achieved, but heat resistance is insufficient as they soften at around 70°C
Solution Approach 1:
The invention uses a multilayer sheet comprising an A-PET layer and a functional resin layer (such as NY resin) to combine the transparency of A-PET with the heat resistance and dropping resistance of the functional resin layer, resolving the contradiction between transparency and heat resistance
Solution Approach 2:
The invention changes the crystallinity parameter of the A-PET layer through controlled stretching and heat-setting processes, increasing crystallinity to improve heat resistance while maintaining transparency, allowing the material to resist temperatures up to 125°C
2Temperature
If PP sheet is used, then high heat resistance is achieved, but transparency is inferior
Solution Approach 1:
The invention combines A-PET layer (providing transparency) with functional resin layer (providing heat resistance), creating a composite structure that achieves both high transparency and high heat resistance simultaneously, overcoming the limitations of using PP alone
3Temperature
If conventional heat-resistant transparent container is used, then high heat resistance and transparency are achieved, but ability to keep quality of foods is insufficient
Solution Approach 1:
The invention introduces a functional resin layer with oxygen barrier properties into the multilayer structure, which prevents oxygen penetration and maintains food quality over extended periods, thereby improving reliability for long-term food storage while maintaining heat resistance
Solution Approach 2:
The invention assigns different functional properties to different layers: the A-PET layer provides transparency and structural integrity, while the functional resin layer specifically provides oxygen barrier properties to maintain food quality, creating localized functional optimization
4Temperature
If conventional heat-resistant transparent container is used, then high heat resistance and transparency are achieved, but resistance to dropping is required to be improved
Solution Approach 1:
The invention incorporates a functional resin layer (such as NY resin) known for its high strength and impact resistance properties, which enhances the overall dropping resistance of the container structure while maintaining the heat resistance provided by the A-PET layer
Solution Approach 2:
The invention places the high-strength functional resin layer in specific positions within the multilayer structure to provide localized reinforcement against dropping impacts, while the A-PET layer maintains transparency and overall structural integrity
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The multilayer container achieves high heat resistance up to 125°C, maintains food quality, and provides improved dropping resistance while maintaining transparency and gloss, effectively addressing the limitations of existing containers.
Implementation Method 1
the multilayer sheet is heated, primarily stretched and then primarily heat-set
Implementation Method 2
crystallinity of the A-PET layer is increased to 20% or more
Implementation Method 3
molded with heating in a mold of a thermoforming machine while secondary stretching is performed
Data Source
Figure 1~2
Figure 3
AI summary
This invention relates to a method of making a multilayer container which comprises: a primary stretching and heat-setting process wherein a multilayer sheet comprising a A-PET layer, a functional resin layer and a sealant layer, is heated, primarily stretched and then primarily heat-set, and a secondary stretching and heat-setting process wherein the multilayer sheet treated in the primary stretching and heat-setting process is molded with heating by a mold of a thermoforming machine while secondary stretching is performed, followed by secondary heat-setting in the same mold.