1.Product features
2.Application
An important functional dye for the production of pressure-sensitive materials
3.Production Method
Example 1: Add 21.5 g (purity 97.0%) of 2-[4,4′-bis(dimethylamino)diphenylmethyl]-5-dimethylaminobenzoic acid to a 500 mL three-neck flask, followed by 250 mL of deionized water. Stir the resulting suspension while adding 21.5 g of activated carbon (model: SHIRASAGI-C, produced by Takeda Chemical Industries Co., Ltd.) and 2.0 g of 49% NaOH aqueous solution. Heat the reaction system to 90–95°C and maintain this temperature range. During the reaction, introduce air into the reaction system at a rate of 400 mL/min for 9 hours. After the reaction is complete, filter the reaction mixture while hot, collect the filter cake, and re-slurry it with deionized water. Slowly add 19.5 g of 36% HCl aqueous solution to the slurry until the solid is completely dissolved. Then, filter to remove the activated carbon. Adjust the pH of the filtrate to 7.0 with 49% NaOH aqueous solution to precipitate the target product crystals. The crystals were collected by vacuum filtration, washed with cold water, and dried under vacuum, yielding 20.1 g of 3,3-bis(4-dimethylaminophenyl)-6-dimethylaminophenyl phthalate with a yield of 95.4%. HPLC analysis showed a byproduct formation rate of 1.5% and a reaction selectivity of 98.4%.
