Views: 0 Author: Site Editor Publish Time: 2021-09-30 Origin: Site
There are many types of fixing agents. The structure of fixing agent Y is short but practical. Fixing agent is mainly used as a color fastness agent for printing or dyeing acid dyes. When used to process cotton, silk, rayon, it will enhance the fastness to washing and soap washing. In the sizing process of yarn-dyed fabrics, the use of this product can prevent penetration and color sticking. Color fastness agent Y is also used for the color fastness of lakes and paper dyes. However, it cannot be used to treat intolerant sulfur black dyes and resin finishing agents.
This passage is going to talk about the following advantages of fixing agent:
(1) Fixing agent can help improve the color fastness
(2) Fixing agent can improve the sweat fastness of fabric
(3) Cooperation between fixing agent and other additives
Use the covering performance of the fixing agent on the fabric to improve the color fastness.
From many experiments, we can conclude that the fixing agent with good coverage will have a better fixing effect. Polymers polymerized by olefins can improve color fastness even without reactive groups or cationic groups, because the polymer covering the fabric surface will reduce the dripping and dissolution of the dye. As the molecular weight increases, the fastness will increase. If a reactive group or a cationic group is introduced into the covering material, the color fastness can be improved. The new color fastness usually uses this method.
Use the acid absorption capacity of the fixing agent to improve the sweat fastness of the fabric.
As we all know, reactive dye fabrics are easily broken in acid solutions. In an acidic environment, the covalent bond between the dye and the fiber will be hydrolyzed and destroyed, resulting in reduced sweat. Because sweat contains acidic substances. In order to improve the perspiration fastness, the fixing molecule should have a strong acid absorption capacity. Therefore, the fixing agent molecule should contain nitrogen atoms. The use of polyolamines is superior to polyatomic acid or naphthalene glycol is a strong proof.
The smoothing agent is used in the coloring agent to make the fiber surface smooth and soft, and to improve the rubbing fastness of the fabric. Up to now, the fixing agent can only reach 2 to 3 grades, and cannot reach 3 or more. The reason is that the smoothness is not improved after being covered by the formaldehyde-free fixative. Therefore, the latest global development is dedicated to improving the wet rubbing fastness of the fixer, and it has been sold. These are actually special softeners, such as polyethylene emulsion, amino silicone and so on. These softeners only work for a large amount of time (greater than 50g/L). This additive can only be used in combination with fixing agent. Evolving soft materials can be grafted with fixatives. The grafting method is adopted to introduce the ultraviolet absorber into the fixing agent molecule to improve the light resistance of the dye. The light resistance of reactive dyes is much greater than that of soluble vat dyes and vat dyes. Especially in light colors, the color fastness is not ideal, and it needs to be improved by fixing treatment. Currently, ultraviolet rays can be used to increase the light resistance by half, but the durability is not good. Therefore, seeking more effective methods is the content of scientific research. The introduction of ultraviolet absorbers into the fixative molecules will reduce the anti-ultraviolet effect or remains to be tested.
