Absorbent Product Embossment Sealing and Fluid Diffusion

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing absorbent articles face issues with the overlapped portion opening, leading to spillage of fibers and super absorbent polymers, and the diffusion of body fluids is inhibited due to adhesive bonding, reducing absorption efficiency.

Innovation Solution

An absorbent article design featuring a permeable front-side sheet, a back-side sheet, and an absorber enveloped by an enveloping sheet with embossments on the front surface, where the overlapped portion is sealed by embossments and adhesive is avoided in the longitudinal area of the overlapped portion to prevent opening and enhance fluid diffusion.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If adhesive is applied to bond the overlapped portion of the enveloping sheet, then the overlapped portion is securely sealed, but the adhesive acts as a wall that inhibits body fluid diffusion and reduces absorption speed

Engineering Contradiction:
Improvesealing of overlapped portionVSAvoidabsorption speed
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The adhesive is completely removed from the overlapped portion area. Instead of applying adhesive to the entire overlapped portion, the patent extracts the adhesive application to only the non-overlapped areas, leaving the overlapped portion free of adhesive to allow unrestricted body fluid diffusion while maintaining sealing through the embossed structure alone

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

Different regions of the enveloping sheet are given different properties: the overlapped portion is designed with embossed sealing structures and no adhesive to promote fluid diffusion, while the non-overlapped portions use adhesive bonding for secure attachment. This local differentiation allows the overlapped portion to function as a fluid diffusion pathway while other areas provide structural bonding

Inventive Principle:
Principle #3Local quality

2Reliability

If the overlapped portion is sealed with adhesive, then the absorber is securely enclosed, but the adhesive creates barriers that reduce the diffusion area for body fluid

Engineering Contradiction:
Improveenclosure of absorberVSAvoiddiffusion area
Core Design Contradiction:
ReliabilityVSArea of stationary object

Solution Approach 1:

The adhesive is extracted from the overlapped portion to prevent it from creating diffusion barriers. The patent specifically removes adhesive application from the overlapped area, allowing the body fluid to diffuse freely across the entire overlapped portion without encountering adhesive walls, thereby maximizing the effective diffusion area

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The enveloping sheet is designed with localized bonding: adhesive is applied only to the non-overlapped front and rear ends for secure enclosure, while the overlapped side portions remain adhesive-free to provide maximum diffusion area. This creates different functional zones within the same structure

Inventive Principle:
Principle #3Local quality

3Ease of manufacture

If embossments are formed on the enveloping sheet to seal the overlapped portion, then the sealing is achieved without adhesive, but the embossments may not provide sufficient sealing force on their own

Engineering Contradiction:
Improveadhesive-free sealingVSAvoidsealing strength
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

The sealing strategy is locally optimized: embossed structures are formed specifically at the overlapped portion to provide mechanical interlocking and sealing, while adhesive bonding is applied at the non-overlapped portions for additional secure attachment. This localized differentiation allows each region to contribute its optimal sealing mechanism

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent merges two sealing mechanisms: mechanical embossing at the overlapped portion and chemical adhesive bonding at the non-overlapped portions. By combining these two different sealing approaches in different locations, the overall sealing reliability is enhanced while maintaining the benefit of adhesive-free overlapped areas for fluid diffusion

Inventive Principle:
Principle #5Merging (Combining)

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 design securely seals the overlapped portion, preventing spillage and allowing for smooth fluid diffusion and absorption, enhancing the wearability and absorption capacity of the absorbent article.

Implementation Method 1

an embossment formed in a front surface of the permeable front-side sheet... Forming the embossment to overlap the overlapped portion makes it possible to securely seal the overlapped portion

Methodology Applied
Scientific EffectCompression: Compression

Implementation Method 2

a permeable front-side sheet... allows for smooth fluid diffusion

Methodology Applied
Scientific EffectDiffusion: Diffusion

Implementation Method 3

improve the diffusibility of a body fluid in the absorber

Methodology Applied
Scientific EffectCapillary action: Capillary Action

Implementation Method 4

an absorber enveloped by an enveloping sheet and disposed between the permeable front-side sheet and the back-side sheet... absorb and retain the body fluid

Methodology Applied
Scientific EffectAbsorption: Absorption (physical)

Data Source

PatentEP3156020B1Absorbent product
Publication Date: 2020.10.14 DAIO PAPER CORP
  • EP3156020B1 patent drawingFigure 1
  • EP3156020B1 patent drawingFigure 2
  • EP3156020B1 patent drawingFigure 3

AI summary

[PROBLEM] To prevent an overlapping portion formed by overlapping the side portions of an enveloping sheet for enveloping an absorber from opening, and to enable a fluid to smoothly diffuse in the absorber. [SOLUTION] An incontinence pad (1) includes a permeable front-side sheet (3), a back-side sheet (2), an absorber (4) enveloped by an enveloping sheet (5) and disposed between the permeable front-side sheet and the back-side sheet, and bilaterally-symmetric embossments (10) formed in a front surface of the permeable front-side sheet (3). An overlapped portion (9) is formed on a front side of the absorber (4) along a longitudinal direction by overlapping the side portions of the enveloping sheet (5). The longitudinal length of one of the bilaterally-symmetrical embossments (10) that overlaps the overlapped portion (9) is greater than or equal to 70% of the longitudinal length (LS) of the overlapped portion (9), and the lateral length of one of the bilaterally-symmetrical embossments is greater than or equal to 10% of the lateral length (WS) of the overlapped portion (9). An adhesive for bonding the side portions of the enveloping sheet (5) is not applied to a longitudinal area of the overlapped portion (9) where the embossment (10) is formed.