Color fastness

Color fastness is a kind of color fastness, also called color migration fastness or color fastness to bleeding. It refers to the migration and staining of dye or residual floating color on the fabric, which mainly reflects the fabric after washing or raining. The degree of contamination that causes the dye to dissolve and migrate to the white or light-colored base fabric comes from Japan and is also called the "Daimaru method" in the Japanese test method.

Color fastness has become one of the common test items in Japan. Generally, it is required to reach level 4 or above 4-5. It is mainly manifested in medium and dark colors. It is often related to staining fastness. If the color fastness is good, the color fastness to weeping will be good.

Test principle:

One end of the sample is immersed in the water containing the reagent, and the degree of color pollution caused by the rising effect of the water is evaluated by the pollution gray card. Required test materials: balance, beaker, volumetric flask, room temperature dyeing machine.

Experiment method:

1. Cut a 3cmx2.5cm size sample. When the patterned fabric cannot cut all the colors into one sample, cut the dark color (the most delicious color).

2. Cut the cotton-added white cloth into a size of (length) 20~25cm x (width) 2.5cm.

3. Place the test piece under the cotton-added white cloth, and sew a thread at each end of the 1.5cm overlapped white cloth.

4. Preparation of non-ionic surfactant solution: Dissolve 0.5 g of non-ionic surfactant in 1000 ml of distilled water.

5. Immerse one end of the test piece in the test solution to a depth of 2cm, and place it for 2 hours at room temperature according to the standard method of each company.

6. Remove the solution and allow the test piece to dry naturally in its original state.

7. Judgment: Use the JIS staining gray card to grade the sample (the staining of the white or light-colored parts of the sample).