Multilayer Packaging Film Structure for Fluid Products

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing multilayer packaging films for fluid products lack satisfactory mechanical and optical properties, as well as adequate barrier and seal stability, especially when exposed to thermal and chemical treatments.

Innovation Solution

A co-extruded multilayer film structure comprising a polyamide core layer, directly adhered tie layers, high density polyethylene intermediate layers, and ethylene/alpha olefin copolymer outer layers, with optional EVOH barrier layers, providing improved mechanical, chemical, and optical properties, and enhanced sealability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If standard multilayer structures (e.g., polyamide core with ethylene/alpha olefin copolymer outer layers) are used, then basic packaging functionality is achieved, but mechanical and optical properties are insufficient

Engineering Contradiction:
Improvemechanical propertiesVSAvoidfilm structure complexity
Core Design Contradiction:
StrengthVSDevice complexity

Solution Approach 1:

The patent employs a composite multilayer structure combining polyamide core layer, tie layers, HDPE intermediate layers, and ethylene/alpha olefin copolymer outer layers. This composite approach enhances mechanical properties by integrating materials with complementary strengths, where each layer contributes specific functional characteristics to achieve superior overall performance.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The film is divided into multiple functional layers with distinct roles: the polyamide core provides structural integrity, tie layers ensure interlayer adhesion, HDPE intermediate layers enhance sealability, and outer layers provide barrier properties. This segmentation allows optimization of each layer's function while maintaining overall film performance.

Inventive Principle:
Principle #1Segmentation

2Illumination intensity

If existing multilayer films are used, then packaging functionality is provided, but optical properties (clarity and gloss) are not satisfactory

Engineering Contradiction:
Improveoptical clarityVSAvoidlayer structure complexity
Core Design Contradiction:
Illumination intensityVSDevice complexity

Solution Approach 1:

The patent applies local quality by assigning specific materials to specific layers based on their optical and functional characteristics. The outer layers use ethylene/alpha olefin copolymer for optimal optical clarity, while inner layers use materials optimized for mechanical strength and sealability. This localized material selection ensures each layer contributes to overall optical performance without compromising other properties.

Inventive Principle:
Principle #3Local quality

3Reliability

If conventional film structures are used, then basic sealability is achieved, but seal stability under thermal and chemical treatments is insufficient

Engineering Contradiction:
Improveseal stabilityVSAvoidfilm structure complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The HDPE intermediate layers act as mediators between the polyamide core and outer layers, providing a transition zone that enhances seal stability. HDPE's thermal properties facilitate reliable sealing while its compatibility with both polyamide and ethylene/alpha olefin copolymer ensures stable interlayer bonding under thermal and chemical treatments.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent extracts the sealing function into a dedicated HDPE intermediate layer, separating it from the structural polyamide core and barrier outer layers. This extraction allows the seal layer to be optimized specifically for thermal and chemical resistance without compromising the functions of other layers.

Inventive Principle:
Principle #2Taking out (Extraction)

4Stability of the object's composition

If simple film structures are used, then manufacturing is easier, but barrier properties and chemical stability are inadequate

Engineering Contradiction:
Improvechemical stabilityVSAvoidfilm structure complexity
Core Design Contradiction:
Stability of the object's compositionVSDevice complexity

Solution Approach 1:

The polyamide core layer provides inherent chemical stability and barrier properties, while the tie layers and outer layers add complementary chemical resistance. This composite structure achieves superior chemical stability and barrier performance that cannot be obtained with single-material films.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

Each layer in the multilayer structure serves multiple functions: the polyamide core provides structural integrity and chemical stability, tie layers provide both adhesion and chemical resistance, HDPE intermediate layers offer sealability and chemical stability, and outer layers provide barrier properties and chemical resistance. This multi-functionality reduces the need for additional specialized layers.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Data Source

PatentUS8734922B2Multilayer film for packaging fluid products
Publication Date: 2014.05.27 CRYOVAC INC

AI summary

Co-extruded multilayer packaging films suitable for packaging fluid products, showing a very good balance of mechanical, chemical and, optionally, barrier properties, good sealability, heat resistance and unexpectedly improved optical properties, a process for their manufacturing, pouches and packages obtained from them, are disclosed. These films comprise a core layer (D) comprising a polyamide; two tie layers (C), directly adhered to the opposite surfaces of the core layer; at least one intermediate layer (B), directly adhered to the opposite surface of a tie layer (C), comprising high density polyethylene; and two outer layers (A) comprising an ethylene/alpha olefin copolymer.