Dispersing Agent NNO-Leveling Agent in Leather Dyeing

Dyeing is an important process in the production of light leather. Through dyeing, leather can present various bright colors and increase the variety of colors to suit various uses. Leather dyeing not only needs to give leather a bright and pure hue, but also requires the color to be as uniform as possible and high dyeing fastness.

In the modern leather industry, suede leather accounts for a certain proportion. Because suede leather is not painted, the suede color should be uniform, full and pure; for the front leather, heavy dyeing and light coating is a trend, which undoubtedly puts higher requirements on dyeing. The rational use of dyeing auxiliaries can help improve the dyeing effect, and it is also possible to reduce the leather production process, save the amount of dye, and reduce the color of dyeing waste liquid. Leather dyeing auxiliaries can be divided into leveling agents, darkening agents and fixing agents according to their functions.

Because leather has certain part differences, and the dyeing process is a complex physical and chemical process, it is easy to cause uneven coloring of leather. In order to improve the uniformity of dyeing and the permeability of dyes in leather, leveling agents are often added during dyeing to achieve the purpose of uniform dyeing.

The leveling effect is generally achieved by slowing down the contact between the dye and the leather (i.e., slow dyeing), or by moving the dyed dye from the dark part of the leather to the light part (i.e., migration dyeing).

There are two main types of leveling agents. One type has a strong affinity for collagen fibers. It uses its adsorption on collagen fibers to delay the dyeing of the dye. For example, our Dispersing  Agent NNO can delay the dyeing of anionic dyes. The other type has a certain affinity for the dye. It first polymerizes with the dye to delay the action of the dye and leather, such as the Peyegal series surfactants and the OP series surfactants, which are polyoxyethylene ether surfactants.