Indigo dispersion dye grinding and dispersing machine

Indigo dye has been widely used for dyeing cotton fabrics, but the pre-treatment process is crucial when dyeing synthetic fibers, and often causes the dyed fabric to harden Many companies have overcome this challenge by dyeing the amorphous parts of synthetic fiber surfaces. The dyes contain preparations that can reduce alkalinity and do not require pre-treatment At present, the production of denim fabric in the world is divided into two methods: sheet dyeing combined with pulp dyeing and ball warp bundle dyeing. In China, the former is the main method, and indigo is mainly used as the dye, while some sulfide dyes and other reducing dyes are also selected

Dispersion stability of dispersed dyes:

Dispersed dyes are immediately dispersed into small particles when poured into water, and the particle size distribution follows a binomial expansion, with an average value ranging from 0.5 to 1 micron. The particle size of high-quality commercial dyes is very close, with a high percentage, which can be indicated by the particle size distribution curve. Dyes with poor particle size distribution have coarse particles of varying sizes and poor dispersion stability. If the particle size significantly exceeds the average range, small particle recrystallization may occur. Due to the increase in recrystallized large particles, dye precipitates and deposits on the walls or fibers of the dyeing machine.

In order to make the dye particles into stable water dispersions, there should be sufficient concentration of boiling dye dispersants in the water. The dye particles are surrounded by dispersants to prevent the dyes from getting close to each other and to prevent them from aggregating or clumping together. The charge repulsion of anions contributes to the stability of the dispersion. Common anionic dispersants include natural lignosulfonates or synthetic naphthalene sulfonic acid dispersants, as well as non-ionic dispersants, mostly alkylphenol polyoxyethylene derivatives, specifically used for synthetic paste printing.

Factors affecting the dispersion stability of dispersed dyes:

Impurities in the original dye may have adverse effects on the dispersion state. The change in dye crystallization is also an important factor, as some crystalline states are easily dispersed while others are not. During the dyeing process, the crystal state of the dye may sometimes change.

Dyes are dispersed in aqueous solutions, and due to external factors, the stable state of dispersion is disrupted, which may result in increased dye crystallization, particle aggregation, and flocculation.

The difference between aggregation and flocculation is that the former can disappear again, is reversible, and can be dispersed by stirring, while the dye in flocculation cannot be restored to a stable dispersion. The consequences of dye particle flocculation include the generation of color spots, slow coloring, reduced color yield, uneven dyeing, and fouling in the dyeing tank.

The factors that cause the instability of dye dispersion are generally: poor dye quality, high dye temperature, long time, too fast pump speed, low pH value, improper additives, unclean fabric, etc.

Indigo is first dissolved in hot water, then heated to around 90 ℃ and added with sodium hydroxide and sodium hydrosulfite. The mixture is kept at 90 ℃ for 3 minutes to prepare a latent color Adjust the pH value with acetic acid, add polyester fabric, dye at room temperature, heat up to 35 ℃ at a rate of 3 ℃/min for 30 minutes, then heat up to 120 ℃ at a rate of 2 ℃/min, continue dyeing for 20 minutes, and cool down to 40 ℃ at a rate of 3 ℃/min Take out the fabric sample, rinse, fully ventilate and oxidize for 5 minutes, soap wash, and dry Among them, the soap boiling method after fabric dyeing, the soap boiling solution prescription is 2g/L anhydrous sodium carbonate, 5g/L standard soap flakes, temperature of 60 ℃, and time of 20min Process flow: After oxidation, the fabric is boiled with soap, washed with water, and dried.

Grinding and dispersing machine is a high-tech product composed of colloid grinding and dispersing machines.

The first level consists of three-level sawtooth protrusions and grooves with increasing precision. The stator can be infinitely adjusted to the desired distance between the rotors. Under enhanced fluid turbulence. The groove can change direction at each level.
The second stage is composed of a stator. The design of the dispersing head also effectively meets the needs of substances with different viscosities and particle sizes. The difference in the design of the stator and rotor (emulsifying head) between online and batch machines is mainly due to the requirements for conveying performance. It is particularly important to note that the difference between coarse precision, medium precision, fine precision, and other types of working heads is not only the arrangement of specified rotor teeth, but also an important difference in the geometric characteristics of different working heads. The width of the slot and other geometric features can alter the different functions of the stator and rotor working heads.

The following is a model table for reference:

Indigo dispersion dye grinding and dispersing machine