Types of dyes
Dyes for aqueous bath
Used for natural and artificial materials, there are many dyes, the choice depends on the textile composition. If the textile is composed of two or more different origins fibers, it is necessary to ensure that none of the materials is degraded.
Most of the time, we used direct or reactive dye on cellulosic fibers, and acid dye for animal fibers.
Used for synthetic materials that cannot be dyed in aqueous baths, because they are hydrophobic.
We used a lot of chemical agents and dying assistants to improve the affinity between the fiber and the dye.
The main dyeing process
- Jigger: The fabric, on a roll, is drawn into a bath, then onto another roll. This operation is performed several times.
- Autoclave: The dye bath is circulated, under pressure, at a temperature above 100°C. Among the various techniques of dyeing in autoclave, there is the beam of fabric.
The fabric or yarn is placed on perforated cylinders, the dye is dissipated under pressure through the perforations of the cylinder to dye the material.
- Padding : The fabric is dyed using a padd. This means that the fabric passes (continuously) through a dye bath, then is extruded (pressed) between two rollers to make the dye penetrate the heart of the fiber.
- Free dyeing : The fabric is rotated in a machine containing a static dye bath.