Custom PU Slides: How to Control Color Rub-Off and Color Transfer

Who this article is for

This article is for footwear brands, private-label teams, wholesalers and importers developing custom PU slides with colored uppers, linings, printed details, coated surfaces or contrasting packaging materials.

It explains how to create a color-performance brief after the target shade has been approved.

Separate appearance from performance

A physical color sample answers an appearance question: is this the intended shade and finish?

A color-fastness or migration test answers a performance question: does color move, rub off, bleed or discolor another material under a defined condition?

Both questions matter, but they use different evidence. A visually accurate sample can still create transfer risk when it contacts skin, socks, tissue paper, a pale outsole, another sandal or packaging.

Map every color-contact combination

Before testing, list the materials that touch or rub against one another. Relevant combinations may include:

• colored upper against a light cloth;
• printed area against skin or socks;
• dark strap against a light sole;
• one sandal against the other inside a pair;
• colored product against tissue paper or a bag;
• adhesive layer next to a pale component;
• stacked products in warm storage.

The test plan should focus on real contact points rather than testing a color chip in isolation.

Define dry rub, wet rub and bleeding separately

ISO 17700:2019 specifies methods for assessing surface-color transfer during dry or wet rubbing and a method for determining the likelihood of color bleeding. Its scope covers footwear uppers, linings and insocks irrespective of material. [1]

The buyer should state which conditions matter for the product. A dry-rub result does not automatically answer a wet-rub question, and neither result automatically covers storage migration.

Record:

• component and color code;
• material and surface finish;
• rub condition;
• agreed method and edition;
• test cloth or adjacent material required by the method;
• number of cycles or endpoint from the approved requirement;
• assessment scale and acceptance rule;
• photographs and specimen identification.

Treat color migration as a contact-storage issue

ISO 17701:2016 addresses discoloration of another footwear material when materials are stored in close contact, including contact involving adhesives. [2]

This is different from rubbing. Migration can become visible after materials remain together under defined storage conditions. A buyer planning a dark strap with a pale sole, or a strongly colored product packed against light material, should include the relevant contact pair in the brief.

Do not assume that changing the packaging solves a material-to-material migration issue. The source and contact path need to be identified.

Approve the actual production construction

Color behavior can depend on more than the color name. The test specimen should represent:

• the production material or an approved equivalent;
• surface coating or print system;
• adhesive and adjacent component where relevant;
• actual color formulation;
• intended curing or processing condition;
• final packaging contact where relevant.

A test on a flat raw-material sheet may support development, yet it may not represent every interaction in a finished sandal. Record what the specimen does and does not cover.

Set the acceptance rule before seeing the result

The test method provides a controlled procedure. The project still needs an acceptance source, such as:

• a retailer or customer requirement;
• a brand specification;
• a destination-market rule;
• an approved reference product;
• a laboratory specification accepted by the parties.

If the project has no confirmed grade or limit, state pending confirmation. Avoid describing a result as colorfast without showing which condition and requirement it met.

Build color checks into change control

Review retesting when a change affects:

• pigment or color formulation;
• material supplier or grade;
• coating, ink or print process;
• adhesive;
• pale adjacent component;
• packaging contact material;
• curing or processing conditions.

Keep the approved shade sample, test report and tested construction version linked in the product record.

Practical color-performance checklist

Before testing, confirm:

• target shade has already been approved;
• all rubbing and contact pairs are mapped;
• dry, wet, bleeding and migration questions are separated;
• material, finish and color versions are identified;
• method and edition are agreed;
• acceptance grade or comparison source is approved;
• the specimen represents the final construction;
• report photographs and observations are required;
• retest triggers are documented.

FAQ

Is Pantone approval enough to control color transfer?

No. A Pantone reference or approved color sample controls the intended appearance. It does not measure rubbing, bleeding or migration performance.

Is dry rubbing enough for bathroom or resort slides?

Not automatically. If wet contact is relevant to the intended use, the test brief should identify the appropriate wet condition and approved requirement.

Can dark products discolor light packaging?

It is possible for certain material, print, adhesive or storage combinations. The actual product-to-packaging contact should be evaluated when it is a project risk.

Can one color result cover every colorway?

Only when the coverage is technically justified. Different pigments, coatings or formulations may perform differently, so the project should define which colors require separate checks.

Sources

1. ISO 17700:2019, Footwear — Test methods for upper components and insocks — Colour fastness to rubbing and bleeding: https://www.iso.org/standard/68279.html
2. ISO 17701:2016, Footwear — Test methods for uppers, lining and insocks — Colour migration: https://www.iso.org/standard/60981.html

Discuss your color-performance brief

Henghao Slide Sandals Factory supports color, surface and branding development for custom PU slide projects. Test conditions and acceptance requirements should be agreed for the actual material and contact combination.

For wider sourcing and development guidance, visit the Custom PU Slide Sandals Buyer Help Center: https://www.henghaoshoes.com/custom-pu-slide-sandals-buyer-help-center/

To discuss a product color and packaging combination, contact Henghao: https://www.henghaoshoes.com/contact/