The dyeing and printing process, including the pretreatment process, is done to remove various impurities from the fabric that is made at the end of the weaving process and to improve some features of the fabric and make the fabric more attractive. We have to use different types of chemicals and chemical agents to complete these processes. Today I will tell you about all those chemicals and their work. So let’s get started without further ado. And lost in the state of Chemical. Textile chemicals and auxiliaries.
Alkalis
1. Caustic Soda, NaOH (Caustic Soda): Caustic soda is commonly used during Scouring, Mercerizing, Dyeing, and Washing. Neutralizes acidic substances. Glycerin, grease, and wax react to form soaps and removes all impurities.
2. Soda Ash, Na2CO3 (Soda Ash): It is widely used in reactive dyeing. It is also used to maintain pH while scouring.
3. Ca (OH) 2: Helps to make bleaching chemicals. Also used in Vat Dye.
Textile chemicals and auxiliaries-Acids
1. Sulfuric acid (H2SO4): It is used in Wool Carbonization. It is also widely used in the washing process.
2. Hydrochloric acid (HCl): This acid is used during souring, dyeing, and washing.
3. Acidic acid, (CH3COOH): It is used when dyeing cloth. It is also used to soothe alkalis.
4. Oxalic acid, (C2H2O4): Oxalic acid is used to remove metallic stains from clothes.
Salts
1. NaOCl: NaOCl is used when bleaching clothes.
2. Ca (OCl) Cl (Bleach powder): It is used for cotton bleaching.
3. Na2S2O4: It is used for vat dyeing and also for protein fiber washing.
Solvents: (Glycerine, Alcohol, Acetone, etc)
When the fabric is printed, it helps to get a bright design. The dye helps in the penetration of molecules into the fabric. Prevents the printing paste from slipping. Makes good printing sheds etc.
Wetting Agents: (Olive oil, T.R oil, Caster oil, etc)
It is used to reduce the surface tension of water so that the pigment or pigment particles easily penetrate the fiber during dyeing. It is also used to get a smooth/fine printing paste during printing. Its use allows the pigment particles to mix well with water and the fabric absorbs very well when the fabric is dyed.
Defoaming Agent or Anti-foaming Agent: (Silicone, defoamers, sulfated oil)
It is used in dyeing baths and printing paste to prevent foam/bubbles when dyeing or printing fabrics. Because if foam or bubbles are created, printing will not be good, even after dyeing, stains will appear on the cloth. Then that cloth will become worthless.
Surfactants (wetting agent, detergent, dispersing agent)
Surfactant is also called Surface Active Agent. Its function is similar to that of a wetting agent, in textile wet processing, it works in a solid-liquid interface and reduces water surface tension. So that the water molecules can easily get into the fabric.
Pers Dispersing Agents: (Glycerine, Alcohol, Acetone, etc)
It works much like solvents, acting as a dispersing agent. It is also used during the dyeing of polyester fabric. It is mainly used during dispersing and VAT dyeing.
