1. What is a Rubbing Color Fastness Tester?
A Rubbing Color Fastness Tester (also called a Crockmeter or Abrasion Color Fastness Tester) is a laboratory instrument designed to evaluate the color transfer resistance of materials when rubbed or abraded. The test determines how firmly dyes or pigments are fixed to the surface of textiles, leather, coatings, or printed materials.
In simple terms, the tester measures how easily color rubs off from a sample onto a white test fabric or pad under controlled rubbing conditions — either dry or wet. The test result helps manufacturers ensure that the color quality of their product will remain stable during everyday use, handling, and cleaning.
This type of testing is essential for industries such as textiles, leather, coatings, automotive interiors, furniture, and printing, where color fastness directly affects product quality, durability, and customer satisfaction.
2. How Does a Rubbing Color Fastness Tester Work?
The Rubbing Color Fastness Tester operates by rubbing a white cloth (usually cotton or wool felt) against the sample surface with a standardized pressure and number of cycles. After rubbing, the degree of color transfer is evaluated visually or instrumentally using a gray scale or colorimeter.
Testing Procedure:
Prepare the specimen – cut a sample of standard size (usually 50 mm × 140 mm).
Attach it to the test bed of the rubbing tester.
Mount the rubbing finger or head covered with white cotton fabric.
Set test parameters such as stroke length, rubbing load, and number of cycles.
Perform dry and wet rubbing tests separately.
Assess the staining level on the rubbing cloth against a gray scale for color transfer.
The result is expressed on a rating scale from 1 to 5, where:
Grade 5: No color transfer (excellent color fastness)
Grade 1: Severe color transfer (poor color fastness)
3. Types of Rubbing Color Fastness Testers
Depending on the testing method and application, several models are available:
(1) Manual Crockmeter
A simple, hand-operated instrument suitable for quick and routine color fastness checks. The tester includes a handle and a reciprocating rubbing arm that allows consistent rubbing by manual operation.
Features:
Compact and cost-effective
Easy to operate
Ideal for workshop or small lab testing
Common standard: AATCC 8, ISO 105-X12
(2) Motorized Rubbing Fastness Tester
This type is fully automated, ensuring precise and repeatable test results. The motorized design eliminates human error and allows multiple test cycles under uniform pressure and speed.
Features:
Adjustable stroke length and speed
Can perform dry and wet tests
High repeatability and accuracy
Some models support multi-position (2 or 4 stations) testing
Typical applications: Laboratory use for textile, leather, and coating samples.
(3) Leather Rubbing Color Fastness Tester
Specifically designed for leather and coated materials, this tester evaluates the resistance of the leather surface to color transfer caused by rubbing. It may use a circular or linear rubbing motion, often under both dry and wet conditions.
Standards: ISO 11640, EN ISO 20433, ASTM D7255
(4) Fabric or Textile Color Fastness Tester
Used in textile testing laboratories, this model complies with standards such as ISO 105-X12 and AATCC 8. It ensures accurate evaluation of color transfer from dyed fabrics to other materials during wearing or washing.
Applications: Clothing fabrics, upholstery, carpets, non-woven fabrics.
4. Applications of Rubbing Color Fastness Testers
The Rubbing Color Fastness Tester has a wide range of industrial applications. Below are the major sectors that rely on this testing:
(1) Textile Industry
Used to assess the color durability of dyed or printed fabrics, garments, and yarns. Ensures that textile colors will not fade or stain during wearing, washing, or ironing.
(2) Leather Manufacturing
Essential for testing dyed leather, synthetic leather, and coated hides. The rubbing fastness test helps leather producers meet the requirements of furniture, automotive, and footwear industries.
(3) Paints and Coatings
Used to measure the abrasion and color transfer resistance of painted or coated surfaces — especially for powder coatings, plastic components, and automotive interiors.
(4) Printing and Packaging
Ensures that inks and printed colors on labels, packaging materials, and decorative films remain stable during handling or transport.
(5) Automotive Interiors
Assesses color fastness of car seat fabrics, dashboards, and leather trims under rubbing, ensuring long-term appearance and performance.
5. International Test Standards
Rubbing color fastness tests are standardized worldwide to ensure uniform evaluation. Below are the major international standards commonly used:
| Standard | Title / Description | Applicable Material |
|---|---|---|
| ISO 105-X12 | Color fastness to rubbing (Crocking test) | Textiles |
| AATCC 8 | Color fastness to crocking (dry and wet rubbing) | Textiles |
| ASTM D7255 | Abrasion resistance of leather (rotary platform) | Leather |
| ISO 11640 | Color fastness to cycles of to-and-fro rubbing | Leather |
| GB/T 3920 | Color fastness to rubbing (Chinese National Standard) | Textiles |
| JIS L0849 | Rubbing fastness test for dyed textiles | Japan |
| EN ISO 20433 | Leather – color fastness to rubbing using a rotating finger | Leather |
| ISO 105-A03 | Assessment of staining using gray scale | All materials |
Compliance with these standards ensures that test results are globally recognized, allowing manufacturers to meet export and quality certification requirements.
6. Common Issues and Solutions
(1) Inconsistent Test Results
Cause: Uneven sample surface, unstable load, or worn rubbing cloth.
Solution: Replace rubbing pads regularly; ensure flat specimen mounting and calibrated load.
(2) Weak Color Transfer Detection
Cause: Low observation light or poor comparison method.
Solution: Use a standardized gray scale under D65 light source for accurate color evaluation.
(3) Incorrect Wet Test Preparation
Cause: Insufficient water absorption in test cloth.
Solution: Use distilled water, soak cloth for uniform wetting, and squeeze to standard moisture content.
(4) Fabric Slippage or Misalignment
Cause: Loose clamping of sample.
Solution: Secure both ends of the specimen tightly to ensure consistent contact with the rubbing head.
(5) Non-Compliance with Standard
Cause: Using incorrect load, speed, or stroke length.
Solution: Follow the exact parameters specified by ISO or AATCC standards.
7. Factors to Consider When Selecting a Rubbing Color Fastness Tester
When choosing the right tester for your laboratory or production line, consider the following factors:
Material Type: Textile, leather, coating, or printed surface.
Automation Level: Manual for quick checks; motorized for precision testing.
Number of Stations: Single, double, or multi-position testers for higher efficiency.
Test Mode: Linear or rotary rubbing motion.
Compliance: Ensure the instrument meets ISO, ASTM, or AATCC standards.
Data Output: Some advanced models include digital counters, load sensors, or color evaluation systems.
Choosing the proper tester helps ensure consistent quality control and compliance with international requirements.
