PVOH Soluble Film Blend for Fast Dissolution Without Gelling

Solution Overview

Problem

Water-soluble unit dose articles using polyvinyl alcohol (PVOH) films face issues with gelling during dissolution due to interaction with detergent, leading to delayed cleaning onset and residues, especially in short and cold temperature cleaning processes.

Innovation Solution

A water-soluble film comprising a blend of two PVOH homopolymers with specific viscosity and hydrolysis ranges, along with optional additives, to enhance dissolution speed and minimize residues.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If a single PVOH homopolymer is used in the film, then the manufacturing process is simple, but the dissolution speed is insufficient and gelling occurs during dissolution

Engineering Contradiction:

Improvedissolution speedVSAvoidfilm composition complexity

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The film is divided into multiple functional layers with different PVOH homopolymers. The first layer uses a PVOH homopolymer with higher viscosity (12-18 cP) for structural integrity, while the second layer uses a PVOH homopolymer with lower viscosity (4-7 cP) for rapid dissolution. This segmentation allows each layer to perform its specific function optimally without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The invention creates a composite film structure combining two different PVOH homopolymers with complementary properties. The higher viscosity polymer provides mechanical strength and prevents premature rupture, while the lower viscosity polymer ensures rapid dissolution and prevents gelling. This composite approach resolves the contradiction by integrating materials that individually address different aspects of the performance requirements.

Inventive Principle:

Principle #40Composite materials

2Strength

If the film uses higher viscosity PVOH homopolymer to maintain strength, then structural integrity is improved, but dissolution speed decreases and gelling occurs

Engineering Contradiction:

Improvefilm strengthVSAvoiddissolution speed

Core Design Contradiction:

StrengthVSSpeed

Solution Approach 1:

The film is divided into multiple functional layers with different PVOH homopolymers. The first layer uses a PVOH homopolymer with higher viscosity (12-18 cP) for structural integrity, while the second layer uses a PVOH homopolymer with lower viscosity (4-7 cP) for rapid dissolution. This segmentation allows each layer to perform its specific function optimally without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the film are assigned different material properties tailored to their specific functional requirements. The first layer is optimized for mechanical strength and structural support, while the second layer is optimized for rapid dissolution and preventing gelling. This local differentiation allows the film to simultaneously achieve both strength and fast dissolution without compromise.

Inventive Principle:

Principle #3Local quality

3Loss of time

If the film dissolves rapidly, then cleaning onset is accelerated, but film strength is reduced causing premature rupture

Engineering Contradiction:

Improvedissolution timeVSAvoidfilm strength

Core Design Contradiction:

Loss of timeVSStrength

Solution Approach 1:

The film is divided into multiple functional layers with different PVOH homopolymers. The first layer uses a PVOH homopolymer with higher viscosity (12-18 cP) for structural integrity, while the second layer uses a PVOH homopolymer with lower viscosity (4-7 cP) for rapid dissolution. This segmentation allows each layer to perform its specific function optimally without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the film are assigned different material properties tailored to their specific functional requirements. The first layer is optimized for mechanical strength and structural support, while the second layer is optimized for rapid dissolution and preventing gelling. This local differentiation allows the film to simultaneously achieve both strength and fast dissolution without compromise.

Inventive Principle:

Principle #3Local quality

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 film blend achieves rapid dissolution, reduces residues, and maintains structural integrity, ensuring efficient cleaning without film remnants.

Implementation Method 1

a first PVOH homopolymer consisting essentially of vinyl alcohol monomer units and vinyl acetate monomer units and a second PVOH homopolymer consisting essentially of vinyl alcohol monomer units and vinyl acetate monomer units

Methodology Applied

Scientific EffectHydrolysis: Hydrolysis

Implementation Method 2

the interaction between a detergent and the polyvinyl alcohol during initial dissolution and contact with water can give rise to gelling that slows down further dissolution

Methodology Applied

Scientific EffectGelling: Gel

Data Source

PatentEP4650389A1Soluble films, film articles, and methods of making and using same

Publication Date: 2025.11.19 MONOSOL LLC

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AI summary

Water-soluble films, water-soluble unit dose articles, and methods of their manufacture and use. One type of film includes a polyvinyl alcohol resin blend comprising a polyvinyl alcohol resin blend comprising a first PVOH homopolymer consisting essentially of vinyl alcohol monomer units and vinyl acetate monomer units and a second PVOH homopolymer consisting essentially of vinyl alcohol monomer units and vinyl acetate monomer units,