Comparison of test methods for rubbing and dyeing fastness
The fastness to rubbing dyeing test refers to a test in which the colored sample is rubbed with a dry rubbing cloth and a wet rubbing cloth respectively, and then the degree of staining of the rubbing cloth is evaluated. The test results are divided into 5 levels, 5 is better, and 1 is worse. Although the test process is simple, it is a basic evaluation index for dyeing fastness of fabric products, and it is almost one of the items that buyers from all over the world must evaluate when placing orders. The technical conditions of the rubbing fastness test standards in various countries are particularly similar, but there are some differences.
The main factors affecting the fastness to rubbing dyeing and their manipulation measures
During the rubbing process between cloth products and other objects, the color fall off or the degree of staining of the rubbed object is affected by many factors. There are two ways of color shedding and staining: one is that the dye on the fabric comes off or fades and is contaminated on the surface of the friction object; the other is that the colored fiber falls off and adheres to the surface of the friction object.
Dye shedding is the main cause of staining
Although there are certain differences in the covalent bond strength and adhesion formed by reactive dyes with different chemical structures and cellulose fibers, the effects on the fastness of wet rubbing dyeing of colored fabrics are basically the same. When the colored fabric is wet rubbed, the covalent bond formed between the dye and the fiber will not break and cause floating color. The transferred dye usually does not form a covalent bond with the fiber, but only relies on van der Waals force to produce adsorption, that is, floating color.
The wet friction dyeing fastness of the protective fabric produced by the city fabric can reach 3-4 grades, and the dry friction dyeing fastness can reach 4-5 grades, which fully meets the requirements of international standards.