Chlorine-free bleaching fastness is evaluated to see the discoloration of dyed or printed textile products against chlorine-free bleaching. In this study, the fabric sample to be tested according to the type of fabric and according to the standard specified by the customer is sewn onto a companion fabric and washed in suitable conditions in the washing machine. For fabrics carrying more than one color, each color is tested separately. The fabric sample is sewn on one side of the escort fabric. The washing agents used in the washing process are generally: ECE detergent, detergent according to AATCC standard, sodium perborate, free chlorine (from sodium hypochlorite solution) and sodium carbonate.

When chlorine-free bleaching fastness tests are evaluated, the gray scale used for fading assessment is used for color change (TS 423-2 EN 20105-A02).

In order to assess shade and color differences under reproducible conditions, such as chlorine bleaching fastness, fabric samples are taken into the light cabinet and visually color differences are evaluated. Light cabinets produce light close to natural light and are a good alternative to natural light.

Two types of gray scale are used in chlorine-free bleaching fastness tests. One of these is five-scale. The worst fastness value is 1 and the best fastness value is 5. The other gray scale has nine scales. Therefore, more accurate results can be obtained with this scale.

Chlorine-free bleaching fastness to determine the color changes of textile products after chlorine-free bleaching is determined according to the following standards:

• TS 400 EN ISO 105-N02 Textile - Color fastness tests - Part N02: Determination of color fastness to bleaching with peroxide
• TS 2762 EN ISO 105-N05 Textiles - Color fastness tests - Part N05: Determination of color fastness to sulfur dioxide
• AATCC 172 Color consistency in bleaching without chlorine in home laundry cleaning