Water-Soluble Sanitary Pad Coating for Skin Protection and Absorbency

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Sanitary pads cause skin irritation due to occlusion, moisture, and mechanical factors, leading to discomfort and impaired performance, especially in thinner and smaller designs like panty liners, which are prone to folding and increased friction against the skin.

Innovation Solution

A sanitary pad design with a water-soluble formulation applied in a coated zone along the rear edge and longitudinal side edges, forming a boundary that delimits a coated-free topsheet area, providing skin benefits while maintaining absorbency and preventing edge soiling.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If hydrophobic compositions are applied to provide an artificial barrier on the skin, then skin irritation is prevented, but absorbency performance deteriorates

Engineering Contradiction:

Improveskin irritationVSAvoidabsorbency performance

Core Design Contradiction:

Object-affected harmful factorsVSReliability

Solution Approach 1:

The patent changes the chemical parameter of the barrier composition from hydrophobic to water-soluble. This allows the composition to dissolve upon contact with moisture, providing temporary skin protection during application while eliminating the long-term absorbency interference that hydrophobic materials would cause.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The water-soluble barrier composition is applied in advance to protect the skin before bodily fluids contact it. The composition provides prophylactic protection rather than being applied reactively after irritation occurs, and dissolves before interfering with the absorbent core's function.

Inventive Principle:

Principle #10Preliminary action

2Ease of operation

If thinner and smaller sanitary pads are used more frequently, then comfort and flexibility are improved, but occlusion and mechanical impact on skin increase

Engineering Contradiction:

Improvecomfort and flexibilityVSAvoidocclusion and mechanical impact

Core Design Contradiction:

Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The water-soluble barrier composition is applied specifically to the rear third and side edges of the pad where it contacts the skin most frequently. This localized application provides protection exactly where mechanical impact and occlusion occur most, without adding material elsewhere that would compromise the thin, flexible design.

Inventive Principle:

Principle #3Local quality

3Adaptability or versatility

If edges of thinner sanitary pads are more flexible, then adaptability to anatomy is improved, but folding and bunching increase

Engineering Contradiction:

Improveadaptability to anatomyVSAvoidedge stability

Core Design Contradiction:

Adaptability or versatilityVSStability of the object's composition

Solution Approach 1:

The barrier composition forms a thin, flexible film on the pad edges that moves with the flexible edges during body movement. This flexible coating prevents the edges from folding inward and bunching while maintaining the pad's ability to adapt to anatomical contours.

Inventive Principle:

Principle #30Flexible shells and thin films

4Object-affected harmful factors

If water-soluble formulation is applied along edges, then skin friction is reduced, but edge soiling may occur

Engineering Contradiction:

Improveskin frictionVSAvoidedge soiling

Core Design Contradiction:

Object-affected harmful factorsVSObject-generated harmful factors

Solution Approach 1:

The use of water-soluble formulation changes the physical parameter of the barrier material from water-resistant to water-soluble. This allows the composition to dissolve cleanly upon contact with moisture, preventing the formulation from transferring to underwear while still providing friction reduction during the brief period it remains intact.

Inventive Principle:

Principle #35Parameter changes

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 reduces skin irritation and maintains product performance by minimizing friction and edge soiling, ensuring comfortable and effective absorption of bodily fluids.

Implementation Method 1

The topsheet is provided with a water-soluble formulation applied in a coated zone

Methodology Applied

Scientific EffectWater-solubility: Solvation

Implementation Method 2

The sanitary pad comprises a fluid permeable topsheet and a backsheet... ensuring comfortable and effective absorption of bodily fluids

Methodology Applied

Scientific EffectCapillary action: Capillary Action

Data Source

PatentUS20250221864A1Sanitary pad comprising a water-soluble formulation

Publication Date: 2025.07.10 ESSITY HYGIENE & HEALTH AB

AI summary

A sanitary includes a fluid permeable topsheet and a backsheet. The sanitary pad being made up of a front third, a rear third and a central third arranged between the front and the rear third, as seen in the longitudinal direction, the topsheet being provided with a water-soluble formulation applied in a coated zone arranged along the rear edge and the first and the second longitudinal side edges in the rear third of the sanitary pad forming a boundary in the rear third delimiting an inner rear zone including a coated free topsheet area, the inner rear zone extending along the longitudinal centreline, the coated zone being arranged at a distance from the rear edge and from the first and second longitudinal side edges and covers from 25% of a total surface area of the topsheet in the rear third of the sanitary pad.