Coated Abrasive With Discontinuous Island Pattern for Curl Resistance

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional coated abrasive sheets tend to curl in humid environments, leading to operational issues such as reduced flexibility and increased risk of delamination, and existing solutions like pre-flexing are inadequate in preventing curling during use.

Innovation Solution

The development of coated abrasive articles with a discontinuous coating pattern where the make layer, abrasive particle layer, and size layer are coated in registration with each other, creating pervasive uncoated areas on the backing, enhancing curl-resistance, flexibility, and durability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional coated abrasive sheets are used in humid environments, then they provide abrasive functionality, but they tend to curl which reduces flexibility and increases delamination risk

Engineering Contradiction:
Improvecurl-resistanceVSAvoidflexibility
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The coating is divided into discrete pattern features (islands) rather than a continuous layer. Each feature is separated by uncoated areas of the backing, creating a segmented structure that allows the backing to flex uniformly without the restraint of a continuous coating layer, thereby preventing curl while maintaining abrasive functionality.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The coating is applied only in specific discrete areas (islands) rather than uniformly across the entire backing surface. This local application provides coating functionality where needed (at abrasive features) while leaving other areas uncoated to maintain backing flexibility and prevent curling.

Inventive Principle:
Principle #3Local quality

2Strength

If continuous coating layers are applied to secure abrasive particles, then particle attachment is improved, but material usage increases and flexibility decreases

Engineering Contradiction:
Improveparticle attachmentVSAvoidraw material quantity
Core Design Contradiction:
StrengthVSLoss of substance

Solution Approach 1:

The harmful excess coating material is extracted/removed by applying coating only in discrete pattern features rather than as a continuous layer. This takes out the unnecessary material that would otherwise be applied to non-functional areas, reducing raw material consumption while maintaining adequate particle attachment at the coated feature locations.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

Instead of applying excessive coating material across the entire surface, the coating is applied partially only to discrete pattern features. This partial action provides sufficient coating for particle attachment at functional areas while avoiding the material waste and flexibility reduction associated with full-surface coating.

Inventive Principle:
Principle #16Partial or excessive action

3Stability of the object's composition

If continuous coating layers are used, then particle stability is enhanced, but the abrasive article becomes less flexible and more prone to curling

Engineering Contradiction:
Improveparticle stabilityVSAvoidflatness
Core Design Contradiction:
Stability of the object's compositionVSShape

Solution Approach 1:

The coating is segmented into discrete pattern features separated by uncoated areas. This segmentation allows the backing to maintain a flat shape by flexing uniformly in the uncoated areas, while the coated features provide sufficient stability to hold abrasive particles in place during use.

Inventive Principle:
Principle #1Segmentation

4Reliability

If discrete pattern features are used instead of continuous coating, then curl-resistance and flexibility are improved, but coating application complexity increases

Engineering Contradiction:
Improvecurl-resistanceVSAvoidcoating pattern complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The coating application parameters are changed to create discrete pattern features rather than continuous layers. This involves modifying coating process parameters (such as using stencils, screens, or selective deposition methods) to control where coating material is applied, transforming the coating from a simple continuous operation to a patterned application process that achieves superior performance.

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP2797717B1Coated abrasive article and method of making the same
Publication Date: 2021.11.24 3M INNOVATIVE PROPERTIES CO
  • EP2797717B1 patent drawingFigure 1~2a
  • EP2797717B1 patent drawingFigure 2b~3
  • EP2797717B1 patent drawingFigure 4

AI summary

Provided are abrasive articles in which the make layer, abrasive particle layer, and size layer are coated onto a backing according to a coating pattern characterized by a plurality of discrete islands. The coating pattern has features in which all three components are generally in registration with each other, while providing a pervasive uncoated area extending across the backing. Advantageously, this configuration provides a coated abrasive that displays superior curl-resistance compared with previously disclosed abrasive articles. Moreover, this configuration resists loading, resists de-lamination, has enhanced flexibility, and decreases the quantity of raw materials required to achieve the same level of performance as conventional abrasive articles.