Biological buffer has the function of maintaining the pH of the buffer system. It is mainly used in biochemical experiments and diagnostic testing. In addition, buffers also have great applications in industry, such as coatings and dyes. This article describes the application of buffer in the process of plant dyeing.
Many dyes are more sensitive to the pH value of the dye bath. If the pH value of the dye bath is slightly controlled inadvertently, dyeing defects such as light color, color difference, and color flowers will appear. In order to solve the above problems, it is necessary to add an appropriate buffer to the dye bath to maintain the pH value of the dye bath with good stability.
Factors that require buffering agents to adjust pH for fabric dyeing:
The fabric is not cleaned during the pre-treatment process, resulting in a small amount of acidic or alkaline substances brought into the dyeing bath to change the pH value.
Some additives and auxiliaries in the dyeing process are not neutral, which will affect the pH value of the dyeing bath.
The pH value of some dyes is too high or too low. If added to the dye bath, it will cause the pH value of the dye bath to change. For example, the pH value of some disperse dyes is 8.60, and some even reach 10.60.
When the boiler is supplying air, negative pressure may occasionally occur, and acid or alkaline solutions in other containers may be poured into the steam pipe. When the dye bath is heated, these substances are brought into it.
Take the high-temperature and high-pressure overflow dyeing machine to dye polyester fabric with disperse dyes as an example. Since many disperse dyes are more sensitive to the pH value of the dyeing bath, dyeing under different pH conditions will give a large difference in color. Only dyeing in a weakly acidic (pH = 5±0.5) dyeing bath will give the resulting color. The most colorful and pure. In order to make the pH value of the dye bath always maintain good stability during dyeing, a buffer solution of acetic acid and sodium acetate can be prepared.
Disperse dyes, weak acid dyes for wool, reactive dyes and other dye baths require different pH values. Different buffers need to be used to strictly control the pH value of the dyeing process. The pH value of the dyeing bath is determined by the depth of dyeing and the dyeing auxiliaries used. . Desheng is a manufacturer of biochemical buffers and can provide Tris, MOPS or other buffers required by customers.