Wet laid disposable absorbent structures with high wet strength and method of making the same

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing methods for producing wet laid disposable absorbent structures, such as paper towels and facial tissues, face challenges in achieving high wet strength, absorbency, and softness while minimizing the use of polyaminoamide-epihalohydrin (PAE) resins, which generate undesirable byproducts like adsorbable organic halogens (AOXs).

Innovation Solution

The development of a method using ultra-high molecular weight glyoxalated polyvinylamide adducts and high molecular weight anionic polyacrylamide complexes, combined with polyvinylamine, to create absorbent structures with high wet strength and low doses or no PAE resin, thereby reducing AOX byproducts and enhancing absorbency and softness.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If PAE resins are used to achieve high wet strength, then wet tensile strength is improved, but adsorbable organic halogens (AOX) byproducts are generated

Engineering Contradiction:

Improvewet tensile strengthVSAvoidAOX byproducts

Core Design Contradiction:

StrengthVSObject-generated harmful factors

Solution Approach 1:

The patent removes PAE resins from the wet strength system entirely, extracting the harmful component while maintaining wet strength through alternative mechanisms involving fiber-to-fiber bonding and other additives

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent converts the harmful PAE resin system into a beneficial alternative system using natural fiber bonding and environmentally friendly additives, turning the elimination of chemicals into a performance-enhancing approach

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

2Use of energy by moving object

If sheet pressing is used to remove moisture, then energy consumption is reduced, but web thickness and absorbency are lowered

Engineering Contradiction:

Improveenergy consumptionVSAvoidweb thickness

Core Design Contradiction:

Use of energy by moving objectVSVolume of moving object

Solution Approach 1:

The patent applies different treatments to different parts of the web - using pressing only in specific areas while leaving other areas uncompressed to maintain thickness and absorbency, creating local variations in density and porosity

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The drying process is segmented into multiple stages with selective pressing, allowing different portions of the web to be treated differently to balance energy efficiency with structural integrity

Inventive Principle:

Principle #1Segmentation

3Object-generated harmful factors

If PAE resin dosage is reduced to minimize AOX, then environmental harm is reduced, but wet strength decreases

Engineering Contradiction:

ImproveAOX byproductsVSAvoidwet tensile strength

Core Design Contradiction:

Object-generated harmful factorsVSStrength

Solution Approach 1:

The patent changes the fundamental parameters of the wet strength system by eliminating PAE resins and introducing alternative mechanisms including fiber modification, enzymatic treatments, and natural bonding agents that provide strength without AOX byproducts

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite wet strength system combining multiple natural and synthetic components that work synergistically to provide wet strength without relying on PAE resins, including modified cellulose fibers, protein-based additives, and bio-based polymers

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

This approach results in absorbent products with high wet tensile strength, improved absorbency, and softness, while minimizing the presence of undesirable byproducts, achieving properties comparable to products using higher PAE doses without the environmental and performance drawbacks.

Implementation Method 1

ultra-high molecular weight glyoxalated polyvinylamide adducts and high molecular weight anionic polyacrylamide complexes

Methodology Applied

Scientific EffectHydrogen bonding:

Implementation Method 2

high molecular weight anionic polyacrylamide complexes

Methodology Applied

Scientific EffectElectrostatic interaction:

Implementation Method 3

The technologies that use water to form the cellulosic (or other natural or synthetic fiber type) webs that comprise the towel or wipe are called Water-Laid Technologies

Methodology Applied

Scientific EffectWater-laid forming:

Implementation Method 4

Technologies that use air to form the webs that comprise the towel or wipe are called Air-Laid Technologies

Methodology Applied

Scientific EffectAir-laid forming:

Implementation Method 5

adhering the web to a Yankee Dryer. The web is then dried and creped from the Yankee Dryer

Methodology Applied

Scientific EffectThermal drying: Heating

Data Source

PatentUS11751728B2Wet laid disposable absorbent structures with high wet strength and method of making the same

Publication Date: 2023.09.12 BLUEHALO LLC

AI summary

A method of making an absorbent structure including mixing ultra-high molecular weight (“UHMW”) glyoxalated polyvinylamide adducts (“GPVM”) and/or high molecular weight (“HMW”), glyoxalated polyacrylamide and/or high cationic charge glyoxalated polyacrylamide (“GPAM”) copolymers and high molecular weight (“HMW”) anionic polyacrylamide (“APAM”) with the furnish during stock preparation of a wet laid papermaking process.