Solid Laundry Detergent with Carbonate and Carboxylate Builders

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Under-built granular laundry detergents face issues with cation interference causing anionic surfactant precipitation, poor physical characteristics, and reduced cleaning performance, especially in hard-water conditions due to the reduction or removal of zeolite builders, leading to poor whiteness maintenance and fabric integrity.

Innovation Solution

A solid laundry detergent composition comprising alkyl benzene sulphonate, carboxylate polymer, and carbonate salt, with controlled ratios and optional zeolite and phosphate builders, to enhance cleaning performance and physical characteristics by ensuring the carbonate salt to alkyl benzene sulphonate ratio is greater than 1:1 and the carboxylate polymer to alkyl benzene sulphonate ratio is between 0.2:1 and 5:1, maintaining good cake strength and dissolution profiles.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If zeolite builder level is significantly reduced or completely removed to improve dissolution and dispensing performance, then dissolution and dispensing performance is improved, but cation interference increases causing anionic surfactant precipitation and reduced cleaning performance

Engineering Contradiction:
Improvedissolution and dispensing performanceVSAvoidcleaning performance
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent introduces water-soluble builder intermediaries (carbonate salts and carboxylate polymers) that mediate between the need for low zeolite content and the need to prevent cation interference. These intermediaries sequester calcium cations without causing surfactant precipitation, thus maintaining cleaning performance while enabling reduced zeolite formulations.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent changes the chemical composition parameters by replacing water-insoluble zeolite builders with water-soluble carbonate salts and carboxylate polymers in specific ratios. This parameter change transforms the builder system from one that causes dissolution issues to one that maintains both dissolution performance and cleaning effectiveness through proper cation management.

Inventive Principle:
Principle #35Parameter changes

2Productivity

If zeolite builder is reduced or removed to improve dissolution performance, then dissolution performance is improved, but physical characteristics deteriorate resulting in poor cake strength

Engineering Contradiction:
Improvedissolution performanceVSAvoidcake strength
Core Design Contradiction:
ProductivityVSStrength

Solution Approach 1:

The patent creates a composite builder system combining carbonate salts and carboxylate polymers in specific weight ratios. This composite material provides both the water solubility needed for good dissolution performance and the structural properties required to maintain cake strength during storage, resolving the contradiction between dissolution and physical characteristics.

Inventive Principle:
Principle #40Composite materials

3Stability of the object's composition

If phosphate-based water-soluble builders are used to replace zeolite, then water solubility is improved, but phosphate-usage avoidance legislation prevents sufficient incorporation

Engineering Contradiction:
Improvewater solubilityVSAvoidbuilder capability
Core Design Contradiction:
Stability of the object's compositionVSAdaptability or versatility

Solution Approach 1:

The patent segments the builder function into two distinct components: carbonate salts provide water solubility and alkalinity, while carboxylate polymers provide cation sequestration and builder capability. This segmentation allows each component to optimize its specific function within legal phosphate limitations, achieving both solubility and effectiveness.

Inventive Principle:
Principle #1Segmentation

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 composition achieves improved cleaning performance, maintains fabric whiteness, and ensures good physical characteristics, such as cake strength, while minimizing water-insoluble residues and maintaining a clear wash liquor, even in hard-water conditions.

Implementation Method 1

cause the anionic detersive surfactant to precipitate out of solution

Methodology Applied
Scientific EffectPrecipitation: Precipitation

Implementation Method 2

improved the dissolution and dispensing performance of the granular laundry detergent

Methodology Applied
Scientific EffectDissolution: Solvation

Data Source

PatentUS8129323B2Solid laundry detergent composition comprising alkyl benzene sulphonate, carbonate salt and carboxylate polymer
Publication Date: 2012.03.06 PROCTER & GAMBLE CO

AI summary

A solid laundry detergent composition in particulate form comprising a plurality of particulate components, the composition comprises: alkyl benzene sulphonate anionic detersive surfactant; carboxylate polymer; carbonate salt; from 0% to less than 5%, by weight of the composition, of zeolite builder; from 0% to less than 5%, by weight of the composition, of phosphate builder; and essentially free silicate salt; wherein any particulate component that comprises at least 5%, by weight of the particulate component, of alkyl benzene sulphonate anionic detersive surfactant comprises a specific amount of carbonate salt to carboxylate polymer; and wherein the composition has a specific weight ratio of carbonate salt to carboxylate polymer.