Fibrous Absorbent Structures With Controlled Particle Distribution

Solution Overview

Problem

Existing processes for integrating solid additives like fibers and particles into fibrous structures, such as absorbent core materials, result in non-controlled distribution and random arrangement of particles, leading to structural integrity issues, fluid barrier formation, and reduced absorbency due to uneven particle distribution and gel blocking.

Innovation Solution

A controlled particle distribution process is employed to introduce particles into a fibrous structure, ensuring a non-random arrangement by managing the angle and velocity of particle introduction into a filament stream, resulting in a gradient of particle sizes within the structure to mitigate gel blocking and enhance absorbency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If a mixed solid additive stream containing particles and fibers of different size, shape, and density is used in the process, then the structure can be formed with multiple solid additives, but the different solid additives exhibit different trajectories resulting in non-controlled distribution and random arrangement of particles

Engineering Contradiction:

Improveability to incorporate multiple solid additivesVSAvoidparticle distribution control

Core Design Contradiction:

Adaptability or versatilityVSManufacturing precision

Solution Approach 1:

The process segments the solid additives by introducing them separately at different locations and angles rather than mixing them together. Particle streams are introduced at different angles (e.g., 0-30 degrees for first particles, 30-60 degrees for second particles) to achieve controlled distribution while incorporating multiple additive types.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The process creates local quality variations by strategically placing different particle sizes in different regions of the structure. Larger particles are positioned in specific zones where structural integrity is needed, while smaller particles are placed in zones requiring enhanced absorbency, giving different parts of the structure different functional properties.

Inventive Principle:

Principle #3Local quality

2Ease of manufacture

If particles are randomly distributed in the fibrous structure, then the structure can be formed with particles integrated, but gel blocking occurs and absorbency is reduced due to uneven particle distribution

Engineering Contradiction:

Improveparticle integration into structureVSAvoidabsorbency performance

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The process creates local quality variations by strategically placing different particle sizes in different regions of the structure. Larger particles are positioned in specific zones where structural integrity is needed, while smaller particles are placed in zones requiring enhanced absorbency, giving different parts of the structure different functional properties.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The process performs preliminary action by controlling particle distribution during the formation process itself, rather than allowing random distribution and then trying to correct it. The angled introduction of particle streams pre-positions particles to prevent gel blocking before it occurs.

Inventive Principle:

Principle #10Preliminary action

3Quantity of substance

If a higher concentration of particles is present in the structure, then sufficient capacity for liquid retention is provided, but the structure density increases and fluid handling properties are compromised

Engineering Contradiction:

Improveparticle concentration for liquid retentionVSAvoidstructure density

Core Design Contradiction:

Quantity of substanceVSVolume of stationary object

Solution Approach 1:

The process creates local quality variations by strategically placing different particle sizes in different regions of the structure. Larger particles are positioned in specific zones where structural integrity is needed, while smaller particles are placed in zones requiring enhanced absorbency, giving different parts of the structure different functional properties.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The process creates a composite structure with multiple particle sizes and types distributed in a controlled non-random manner. This composite arrangement allows the structure to achieve sufficient liquid retention capacity while maintaining appropriate density and fluid handling properties through the strategic distribution of different particle components.

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 process achieves a non-random arrangement of particles within the fibrous structure, reducing gel blocking and improving absorbency by strategically placing larger particles where permeability is crucial and smaller particles where absorption speed is needed, thereby enhancing the overall performance of the absorbent material.

Implementation Method 1

Known processes of integrating solid additives, such as fibers and/or particles of different size, shape, and density and/or solid additives, such as fibers and/or particles that exhibit different Stokes Numbers, for example pulp fibers and SAP particles, into single structures

Methodology Applied

Scientific EffectStokes Number: Stokes Drift

Data Source

PatentUS12409077B2Structures comprising particles and processes for making same

Publication Date: 2025.09.09 PROCTER & GAMBLE CO

AI summary

Structures, for example fibrous structures, such as absorbent material, for example absorbent core material including particles, for example super absorbent polymer particles (SAP particles), and processes for making same are provided.