How to Adjust the Transparency of Organic Pigments

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Classification：Industry dynamic
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Release time：2022-08-09
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The transparency of organic pigments has an important effect on some specific uses, the main methods to make pigments transparent are the following:

In the azo pigment synthesis process, try to form fine pigment particles, such as adding the diazo component to the coupling component quickly, or adding a specific surfactant to make the coupling component separated into fine particles; the coupling reaction is carried out at a lower temperature, and rapid stirring is adopted to promote the coupling reaction to be carried out faster, and a precipitated product with fine particle size is generated.
After the coupling reaction is completed, increase the temperature. Under the condition that the filtration efficiency is not affected, it is not advisable to heat the temperature too high or keep the heat preservation time too long to prevent the aggregation of fine particles from becoming larger. Adding auxiliary agents, such as classical derivatives of rosin acid, rosin amine and aliphatic amine, in the coupling reaction, the aggregated particles are still relatively easily redispersed and the pigment particle size is kept small.
A more effective process is to use mixed coupling techniques, such as adding a second coupling component, or a second diazo component, to prevent aggregation of the resulting pigment particles, and the reaction product not only has high transparency, but also gives high color strength. In addition, self-derivatives or pigment dispersants can also be added in the synthesis process as a pigment crystal growth inhibitor to prevent further growth of crystal particles and obtain highly transparent pigments.
Control the drying temperature and its variation range. Too high drying temperature or too long drying time will also lead to the reduction of the transparency of the pigment. Even the pulverization process of the dried pigment material, such as the high revolution of the pulverizer and the mechanical structure of the pulverizing equipment, may affect the transparency of the final pigment to a certain extent.
The method of improving transparency can also be obtained by squeezing water.
Yuhong Pigment Ink Use Recommended products: Organic Pigment Red YHR4804, YHR146; Organic Pigment Yellow YHY1235, YHY1407, Lumeijia Yellow 3; Organic Pigment Orange YHO1311, YHO1312.