Polyelectrolyte Complex Coating for Flexible Grease Barrier Packaging

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Packaging materials with polymer-based grease barrier coatings often lack flexibility and are prone to damage at folds, bends, and corners, leading to insufficient grease barrier effects, and may contain harmful substances like heavy metals or fluorocarbons.

Innovation Solution

A method involving the use of a polyelectrolyte complex coating on packaging surfaces, composed of an anionic and a cationic polymer, which provides enhanced grease barrier properties while maintaining flexibility and temperature resistance, and excludes harmful substances.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If polymer-based grease barrier coatings are applied to packaging materials, then grease barrier properties are improved, but flexibility and resistance to damage at folds are worsened

Engineering Contradiction:
Improvegrease barrier propertiesVSAvoidflexibility and resistance to damage
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The patent changes the chemical and physical parameters of the coating by using a polyelectrolyte complex with specific charge ratios (anionic and cationic polymers in defined proportions). This creates a coating that forms a flexible, adherent film rather than a rigid barrier, maintaining grease resistance while allowing the packaging to flex without damage at folds and corners.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The invention uses a composite coating system consisting of two different polymers (anionic and cationic) that form a complex through electrostatic interaction. This composite structure combines the grease-barrier properties of polymer coatings with the flexibility needed for folding packaging, resolving the contradiction between barrier performance and mechanical flexibility.

Inventive Principle:
Principle #40Composite materials

2Reliability

If traditional grease barrier coatings are used, then penetration resistance against fats and oils is improved, but harmful substances such as heavy metals and fluorocarbon compounds may be present

Engineering Contradiction:
Improvepenetration resistance against fats and oilsVSAvoidharmful substances
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent extracts and eliminates harmful substances from the coating composition by using only water-soluble, food-safe anionic and cationic polymers. Traditional coatings containing heavy metals, fluorocarbons, or other harmful additives are replaced with a safe polyelectrolyte complex that provides equivalent or superior grease barrier properties without the harmful contaminants.

Inventive Principle:
Principle #2Taking out (Extraction)

3Reliability

If polymer coatings are applied to provide grease barrier properties, then penetration resistance is improved, but the coatings may contain substances harmful to health

Engineering Contradiction:
Improvegrease barrier propertiesVSAvoidharmful substances in coating
Core Design Contradiction:
ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The patent changes the compositional parameters of the coating to exclude harmful substances entirely. By selecting food-grade, water-soluble polymers with appropriate molecular weights and charge densities, the coating achieves effective grease barrier properties through its polyelectrolyte complex structure without incorporating any harmful additives or contaminants.

Inventive Principle:
Principle #35Parameter changes

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 polyelectrolyte complex coating significantly improves the packaging's resistance to grease and oils, especially in areas prone to bending or folding, while being flexible, temperature-resistant, and free from harmful substances.

Implementation Method 1

the polyelectrolyte complex consisting of at least a first polymer and at least a second polymer, the first polymer being an anionic polymer and the second polymer being a cationic polymer

Methodology Applied
Scientific EffectElectrostatic interaction: Ion Repulsion/Attraction

Data Source

PatentEP2315815B1Process for manufacture of packaging with grease barrier properties
Publication Date: 2014.01.08 BASF SE

AI summary

A process is described for manufacture of packaging, wherein the packaging surface is coated with a polyelectrolyte complex and wherein the polyelectrolyte complex consists of at least one first polymer and at least one second polymer, wherein the first polymer is an anionic polymer and the second polymer is a cationic polymer.  The packagings are characterized by good grease barrier properties.