Practical Technology: Technical Trends of Color Matching

In the foreseeable future, that is, in the next five to ten years, the trend of professional development will gradually abandon the coloring technology of water-soluble dyes under the strict conditions of environmental protection, energy saving, and higher color fastness. The choice of coloring materials will tend to be more hydrophobic and micronized. Hydrophobicity means that the coloring material is insoluble in water, and microparticulation means surface processing with a nanocoloring material whose particle size is below 1000 nm, typically between 50 nm and 80 nm. Today, this development in the color industry has a solid foundation and a good sign. Its solid foundation is the emergence of super dispersants and highly efficient hydrophobic capillary bulking wetting agents; the good signs are that these special pigments suitable for nano-coloring materials have been used in photo printing, color printing, photo and paint, and spray painting industries. Successful application. As textile dyeing and finishing counterparts must understand the momentum of the development of coloring technology.

II. Transformation and Control in Coloring Ideas

1, accurately grasp the dye curve

Traditional theories, such as the three typical adsorption theories of Nassau, Langeer, and Roindrich, only give the isocratic conditions for the concentration distribution of the dye between the coloring material and the dyeing bath, but lack of warming. Under the conditions, the theory of the coloration rate of the dyeing process, at most, gives the empirical equation that deals with the mathematical modelling of the actual dyeing curve. This shows that the actual dyeing is much more complicated than the theoretical treatment.

2. Although dyeing curve and isothermal adsorption curve are mathematically similar and all belong to the exponential curve, the meaning of the two dyeings is totally different. Especially when coloring materials and dyeing aids are changed.

E.g:

1, Diacetate fibers are dyed with disperse dyes. The isothermal adsorption generally satisfies the theory of NASCAR, but when the dyeing vehicle is present, the solute (disperse dye) faces 3 miscible solvents. The partition coefficients of each other have been completely changed. This phenomenon also includes the occasion where many synthetic fibers are dyed with disperse dyes.

2, under acidic conditions, anionic dyes dyed wool, nylon fiber and acrylic dyes dyed acrylic, generally depends on the coloring material at a specific position of the adsorption, that is, Langmuir isotherm adsorption type. When these specific parts are filled, the dye distribution in the fibers can be said to be saturated. When there is a hydrophobic capillary swelling agent, the saturated dye concentration becomes unsaturated, and the color fastness is greatly improved. At this point, the specific location may not necessarily be called specific.

3, the traditional adsorption characteristics of cellulose-stained cotton are not limited by specific parts. Depending on the available surface area of ​​the hole, this is the theory of adsorption by Roindlich. It is also an incomplete theory and can only be expressed by empirical equations. Now encountered nano-material coloring particles, due to the enormous ratio of the table, as well as a wide range of covalent bonding with the coloring material surface.

4, the outstanding advantages of nano-coloring materials: to break the traditional theory of dyeing binding, for example, nano-particle dyeing does not require filling the coloring material from the inside to the outside, which solves the traditional use of a large number of colorants to obtain the table Contradictions of the color density, a large number of saving coloring materials, the amount required only one-tenth to one-twentieth of the traditional; so that coloring material damage greatly reduced; as long as the coloring material has a relatively negative charge of colorant, It is possible to use the coloring of nanocolorants. In this way, the limitations of the three traditional adsorption theories are overcome, and the coloring material of the nano colorant can be used, as long as the nano colorant does not have to be classified too finely, that is, a nano colorant can be used to dye cotton, wool, silk, Hemp, hair, special animal fibers, including cotton, acrylic, polyester, Tencel, Modal, soy fiber, milk fiber, glass fiber, shell buttons, plastic, metal surfaces are not wrong. Because of the formation of covalent bonds, the problem of the color fastness of water-soluble dyes and large particle pigments has been completely solved.