Oil Protecting Layer for Sanitary Topsheets

Solution Overview

Problem

Sanitary articles, such as sanitary napkins and diapers, often cause skin irritation due to occlusion and moisture, and the use of hydrophobic compositions to address this issue can negatively impact absorbency performance.

Innovation Solution

Incorporating a fibrous oil protecting layer between the topsheet and absorbent core with a coating of oil composition and non-ionic surfactants, maintaining a weight ratio of at least 1:1, to enhance skin care and absorbency while preventing oil migration into the absorbent core.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If hydrophobic compositions are applied to the topsheet to provide skin protection, then skin irritation is reduced, but absorbency performance deteriorates

Engineering Contradiction:

Improveskin irritationVSAvoidabsorbency performance

Core Design Contradiction:

Object-affected harmful factorsVSReliability

Solution Approach 1:

The patent divides the topsheet into two functional zones: a hydrophobic composition application area for skin protection and an absorbent core area for fluid absorption. The hydrophobic composition is applied only to specific regions of the topsheet where skin contact occurs, while the absorbent core remains unaffected, thus maintaining both skin protection and absorbency performance.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent introduces an intermediary layer or barrier between the hydrophobic composition and the absorbent core. This intermediary structure prevents the hydrophobic composition from migrating into the absorbent core, thereby protecting the absorbency performance while allowing the skin protection function to be provided by the hydrophobic composition on the topsheet surface.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Object-affected harmful factors

If high amount of oil composition is applied to the topsheet for softness and skin care, then skin beneficial effect is improved, but oil migration into absorbent core increases

Engineering Contradiction:

Improveskin irritationVSAvoidoil migration

Core Design Contradiction:

Object-affected harmful factorsVSLoss of substance

Solution Approach 1:

The patent introduces an intermediary layer or barrier between the hydrophobic composition and the absorbent core. This intermediary structure prevents the hydrophobic composition from migrating into the absorbent core, thereby protecting the absorbency performance while allowing the skin protection function to be provided by the hydrophobic composition on the topsheet surface.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent applies the hydrophobic composition locally to specific regions of the topsheet where skin contact occurs, rather than uniformly across the entire surface. This localized application provides skin protection where needed while minimizing the total amount of oil composition that could potentially migrate into the absorbent core.

Inventive Principle:

Principle #3Local quality

3Reliability

If hydrophobic compositions are applied in low amounts to avoid impacting absorbency, then absorbency performance is maintained, but skin care effect is reduced

Engineering Contradiction:

Improveabsorbency performanceVSAvoidskin irritation

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent divides the topsheet into two functional zones: a hydrophobic composition application area for skin protection and an absorbent core area for fluid absorption. The hydrophobic composition is applied only to specific regions of the topsheet where skin contact occurs, while the absorbent core remains unaffected, thus maintaining both skin protection and absorbency performance.

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 solution provides a softer feel, improved skin care, and maintains high absorbency by retaining the oil in the fibrous layer, reducing friction and chafing, and preventing oil from impairing the absorbent core's performance.

Implementation Method 1

one or more surface active agent(s) including a non-ionic surfactant

Methodology Applied

Scientific EffectSurface tension reduction: Surfactant

Implementation Method 2

The void space provided by the non-absorbent fiber network holds the oil and prevents it to migrate down into the absorbent core

Methodology Applied

Scientific EffectCapillary action: Capillary Action

Data Source

PatentEP3474800B1Absorbent article with an oil composition and an oil protecting layer

Publication Date: 2023.05.31 ESSITY HYGIENE & HEALTH AB

AI summary

The present disclosure relates to a sanitary article such as a sanitary napkin, a panty liner, a diaper or an incontinence pad, comprising a liquid permeable topsheet, a backsheet, an absorbent core enclosed between the topsheet and the backsheet, and a fibrous layer positioned between the topsheet and the absorbent core. The topsheet includes a coating comprising a) an oil composition and b) one or more surface active agent(s) including a non-ionic surfactant, wherein the weight ratio of the oil composition and the surface active agent(s) is at least 1 : 1, and wherein the oil composition is present in an amount of at least 0.3 g/m2 of the topsheet and wherein the fibrous layer is an oil protecting layer consisting essentially of non-absorbent fibers.