Coated Detergent Particles with Inorganic Shell

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing laundry detergent particles face challenges in maintaining stability and flowability, especially under humid conditions, and in achieving a balanced surfactant concentration that avoids either liquid or granular formulations.

Innovation Solution

The development of coated detergent particles with a surfactant core and a sodium carbonate-silicate coating, where the surfactant constitutes 40-90 wt% and the coating comprises 70-100 wt% of sodium carbonate and silicate, with specific dimensions and shapes, enhances stability and flowability while maintaining a concentrated surfactant formulation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If a concentrated surfactant formulation is used, then the unit dose required for washing is reduced, but the particle stability and flowability deteriorate under humid conditions

Engineering Contradiction:
Improvesurfactant concentrationVSAvoidparticle stability
Core Design Contradiction:
Quantity of substanceVSReliability

Solution Approach 1:

The detergent formulation is segmented into a surfactant core and a separate inorganic coating layer. This segmentation allows the surfactant to remain concentrated in the core while the coating provides protective functions for stability and flowability, resolving the contradiction between high surfactant concentration and particle reliability.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

An inorganic coating comprising carbonate and silicate acts as an intermediary layer between the surfactant core and the external environment. This coating mediates the interaction with moisture, preventing water ingress that would otherwise compromise particle stability, while maintaining the concentrated surfactant formulation inside.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Quantity of substance

If a concentrated surfactant formulation is used, then the unit dose required for washing is reduced, but the particle flowability deteriorates

Engineering Contradiction:
Improvesurfactant concentrationVSAvoidparticle flowability
Core Design Contradiction:
Quantity of substanceVSEase of operation

Solution Approach 1:

By segmenting the formulation into core and coating, the inorganic coating can be optimized specifically for flowability without diluting the surfactant concentration. The coating acts as a separate functional layer that improves handling properties while the core maintains high surfactant content.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The inorganic coating changes the physical parameters of the particle surface (roughness, electrostatic charge, moisture content) to improve flowability. This parameter change occurs at the surface level without affecting the internal surfactant concentration, resolving the contradiction between concentration and flowability.

Inventive Principle:
Principle #35Parameter changes

3Reliability

If the particle is designed to prevent water ingress, then stability under humid conditions is improved, but the formulation becomes less concentrated

Engineering Contradiction:
Improveparticle stabilityVSAvoidsurfactant concentration
Core Design Contradiction:
ReliabilityVSQuantity of substance

Solution Approach 1:

The protective function is segmented into a separate inorganic coating layer, allowing the surfactant core to remain concentrated. The coating specifically handles the water ingress prevention function, while the core maintains high surfactant concentration for effective washing at reduced doses.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The inorganic coating serves as an intermediary barrier that prevents water ingress without requiring the surfactant itself to be diluted. The coating absorbs or repels moisture, protecting the concentrated surfactant formulation inside while maintaining particle stability.

Inventive Principle:
Principle #24Intermediary (Mediator)

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 coated particles exhibit improved stability and flowability under humid conditions, allowing for a reduced unit dose in washing and avoiding the drawbacks of liquid or granular formulations, thus offering a middle ground between conventional formats.

Implementation Method 1

the water ingress of carbonate coated particles is reduced by the incorporation of silicate into the coating; this aids stability of the particles

Methodology Applied
Scientific EffectHydrophobic effect: Hydrophobe

Implementation Method 2

large detergent particles flow better after storage in humid conditions by the incorporation of silicate into a carbonate

Methodology Applied
Scientific EffectSurface modification: Coatings

Data Source

PatentEP2627749B1Laundry detergent particles
Publication Date: 2015.03.04 UNILEVER PLC

AI summary

A coated detergent particle having perpendicular dimensions x, y and z, wherein x is from 1 to 2mm, y is from 2 to 8mm, and z is from 2 to 8mm, wherein the particle comprises: (i) from 40 to 90 wt% surfactant selected from: anionic surfactant; and, non-ionic surfactant; (ii) from 20 to 40 wt% water soluble inorganic salts, the water soluble inorganic salts a mixture of sodium carbonate and sodium silicate; and, (iii) from 0 to 3 wt% of a perfume, wherein the inorganic salts are present on the detergent particle as a coating and the surfactant is present as a core, and sodium carbonate and sodium silicate comprise from 70 to 100 wt% of the coating and the ratio of sodium carbonate: sodium silicate is in the range from 4:1 to 2:3.