sweat stain color fastness tester test method

　　The sweat stain color fastness tester is used to test the degree of influence of human sweat, water, or seawater on the color fastness of clothes; Combined with yellowing test paper, yellowing test control cloth, yellowing test film, glass sheet, etc., it can be used for phenolic yellowing test.

　　Purpose and scope:

　　This testing method is used to determine the firmness of colored fabrics to sweat, and can be used for dyeing, printing, and other colored textile fibers, yarns, and various fabrics. It can also be used to test dyes on fabrics.

　　Color fastness, n-prevents any material from changing color or coloring adjacent materials, which may be encountered when developing, testing, storing, and using these materials due to their exposure to any environment.

　　Sweat, n-alkaline liquid excreted from sweat glands.

　　Instruments and materials:

　　Sweat tester, sweat measuring instrument or related device (equipped with plastic and glass sheets).

　　Oven - Convection type.

　　Multi fiber test fabric or FA.

　　Color transmission scale or natural color pollution measurement scale.

　　Test the natural color scale for color changes.

　　Rolling and drying machine.

　　Acidic solution:

　　Prepare one liter with distilled water: 10 grams of sodium chloride, 1 gram of lactic acid, USP85%, 1 gram of Na2HPO4, 0.25 grams of ammonium chloride monohydrate.

　　The pH value of the solution must be 4.3 ± 0.2, measured using a pH meter. Do not use pH test strips because the pH of the pH test strips is not good. If the pH of the prepared acidic solution exceeds the range of 4.1-4.5, it needs to be prepared again to ensure the accuracy of ingredient weighing.