Chitosan Capsule Shell Leakage in Low Surfactant Detergents

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing perfume capsules in water-soluble unit dose detergent articles exhibit high leakage in low water surfactant formulations, leading to reduced fabric freshness benefits and potential product discoloration.

Innovation Solution

The use of perfume capsules with a shell composed of a reaction product of chitosan and a cross-linking agent, specifically a mixture of di- and poly-isocyanates with alpha- and beta-aromatic moieties, which reduces leakage and enhances fabric freshness.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If perfume capsules with reduced petrochemical content (chitosan-based) are used, then environmental sustainability is improved, but perfume leakage increases in low water surfactant formulations

Engineering Contradiction:

Improveenvironmental sustainabilityVSAvoidperfume leakage resistance

Core Design Contradiction:

Object-affected harmful factorsVSReliability

Solution Approach 1:

The patent modifies the chemical parameters of the shell by using a mixture of two or more di- and/or poly-isocyanates with different aromatic moieties (alpha- and beta-aromatic isocyanates) instead of a single isocyanate type. This compositional parameter change creates a more robust cross-linked network that prevents perfume leakage while maintaining the chitosan-based environmentally sustainable formulation.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite shell structure combining chitosan (biopolymer) with a complex isocyanate cross-linking system comprising multiple aromatic isocyanates. This composite material approach integrates the environmental benefits of biodegradable chitosan with the leakage-resistant properties achieved through the multi-component isocyanate system.

Inventive Principle:

Principle #40Composite materials

2Object-affected harmful factors

If perfume capsules with reduced petrochemical content are used, then environmental sustainability is improved, but fabric freshness benefits are reduced

Engineering Contradiction:

Improveenvironmental sustainabilityVSAvoidfabric freshness delivery

Core Design Contradiction:

Object-affected harmful factorsVSQuantity of substance

Solution Approach 1:

By changing the isocyanate mixture composition to include both alpha- and beta-aromatic isocyanates in specific proportions, the patent optimizes the shell's perfume release characteristics. This parameter adjustment ensures that perfume is released at the appropriate rate during the wash cycle, delivering effective fabric freshness while maintaining environmental sustainability.

Inventive Principle:

Principle #35Parameter changes

3Ease of manufacture

If single isocyanate cross-linking agents are used, then manufacturing simplicity is maintained, but perfume leakage resistance is insufficient

Engineering Contradiction:

Improvemanufacturing simplicityVSAvoidperfume leakage resistance

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The patent merges multiple isocyanate components (two or more di- and/or poly-isocyanates with aromatic moieties) into a single cross-linking system that works synergistically. This combination approach enhances leakage resistance while maintaining practical manufacturability, as the isocyanate mixture can be applied through existing encapsulation processes.

Inventive Principle:

Principle #5Merging (Combining)

4Productivity

If low water surfactant formulations are used, then detergent efficiency is improved, but perfume capsule stability deteriorates

Engineering Contradiction:

Improvedetergent efficiencyVSAvoidcapsule stability

Core Design Contradiction:

ProductivityVSStability of the object's composition

Solution Approach 1:

The patent develops a composite shell material combining chitosan with a multi-component aromatic isocyanate cross-linking system. This composite structure provides enhanced stability and integrity in low water surfactant environments, preventing capsule failure while allowing the detergent formulation to maintain its high efficiency characteristics.

Inventive Principle:

Principle #40Composite materials

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 described solution significantly reduces perfume leakage and improves fabric freshness performance in water-soluble unit dose detergent articles, even in low water surfactant formulations, while maintaining product color stability.

Implementation Method 1

the shell comprises a polymeric material that is the reaction product of chitosan, preferably derived from an aqueous phase, and a cross-linking agent, preferably derived from an oil phase

Methodology Applied

Scientific EffectChemical reaction: Chemical Bonding