Seek technology for liquid sulfur dyeing

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Since powdered sulfur dyes contain a high amount of gypsum, liquid sulfur dyes (especially Yellow Brown 5G, Red Brown B3R) suffer from severe crystallization due to the presence of antioxidants; whereas Black BN, with its high content and strength, does not exhibit crystallization. As a result, crystallization occurs during storage and transportation in winter, which affects their usability. Technical challenge: Since the reducing agents used in the production of liquid sulfur dyes are sodium hydrosulfide and sodium sulfide, their use by customers is not very environmentally friendly. The foreign company Clariant produces low-sulfur liquid sulfur dyes using sodium hydroxide and grape pomace as reducing agents, which is an environmentally friendly approach. What is produced are true achromatophores, with a high strength of the dye (providing strong coloring). The company is unsure which research institution could develop this product to replace imported ones.