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2. Product technical indicators:
Appearance: golden or orange crystalline powder
Content: ≥93%

3. Performance:
The product is easily soluble in water, has moderate coupling activity, and is compatible with 2-hydroxy-3,6-dinaphthalenesulfonic acid. The coupling appears blue-violet: when coupled with AP, it appears purple-blue.

4. Purpose:
Mainly used in the production of high-speed dry blue thread paper and medium-speed dry black thread paper.