The Operational steps of Washing Fastness Tester

refers to the situation of fade and discoloration of dye textiles when soaping. The main machines used in washing color fastness  are Washing Color Fastness Testers. Generally, there are two indicators measured in washing colorfastness test, including testing  fade of original sample and staining of white cloth. Fade of original sample is the color change of dyed textiles before and after soaping. Staining of white cloth is the situation of staining of white cloth which it is soaping together with dyed fabrics.

 

1、Take two pieces of fabric about 5cm by 5cm, one of which is undyed cotton and the other undyed wool. Stitch them together along one side.

2、Take some sample strips of the dyed yarn and spread them evenly between the two pieces of cloth so that they overlap both sides. If dyed fibre is being tested a combed sample can be used in place of the yarn.

3、Sew around all four sides of the cloth so that the yarn is held in place.

4、Prepare a similar specimen with dyed materials that has satisfactory properties and place them in two jars with screw lids containing a solution of 5gm per litre soap or detergent solution at 30oC.

5、Agitate the two jars gently for 30mins, then remove the fabrics and wash them gently in clean water for 5mins. Open the stitching and separate the pieces to dry in air. Examination:

6、Place the dyed yarn next to a sample of the same material which has not been tested, and compare the change which has taken place. Compare also with the control sample with satisfactory properties. If the dyeing being tested shows equal or less change than the satisfactory sample, then it is as good as the satisfactory sample.

7、Place the wool and cotton cloths next to samples of the same material which have not been tested and compare them with the cloths that have been tested with a satisfactory dyeing. Equal or less staining shows equal or better fastness.