| use | weak acid brilliant blue FFR is suitable for dyeing wool, silk and their blended fabrics, and can also be directly printed on wool and silk fabrics with bright and bright colors. Levelness and extraction dyeing performance are good. When used for dyeing wool with other fibers in the same bath, acetate fiber, cellulose fiber and nylon are slightly stained. It is also used for coloring leather and matchstalk, and can be used for shoe polish to brightening. |
| Production method | Using N-ethyl-N-(m-sulfonic benzyl) m-toluidine and p-diethylaminobenzaldehyde as raw materials, first The two are condensed under the protection of nitrogen, and then oxidized and refined to obtain the product. The finished product is filtered, dried and crushed.. N-ethyl-N-(m-sulfonic benzyl) m-toluidine 132.2g (0.433mol), p-diethylaminobenzaldehyde 39.2g (0.23mol), oxalic acid aqueous solution (10%) 200mL and water 1000mL were added to the condensation reactor, and the reflux was under N2 protection for 1.5h. Then 150mL of sodium acetate aqueous solution (18%) was added and reflux continued for 1.5h. It is cooled to 95 ℃ for filtration, washed with water and methanol successively, and dried in vacuum at 80 ℃ to obtain about 142g of product. Add 23.1g (0.3mol) of the above condensation product, 400mL of 50% acetic acid and 200mL of oxalic acid solution (10%) into the oxidation reactor, stir and dissolve, cool to -10 ℃, then quickly (within 30s) add sodium dichromate aqueous solution (prepared from 3.15g sodium dichromate and 20mL of water), keep the temperature at -8-5 ℃, and stir quickly. Then 600mL of sodium sulfate saturated solution was added at 12 ℃, and then 200mL of concentrated ammonium hydroxide solution was added to neutralize acetic acid, cool to 0 ℃, and filter to obtain oxidation products. The above-mentioned oxidation product filter cake, 60mL of sulfuric acid and 600mL of water are added into the refiner, stirred and dissolved, then sodium hydroxide aqueous solution (68g 50% sodium hydroxide solution diluted to 120mL) is added below 10 ℃, stirred for 40min, filtered, filtrate (about 1400mL) is taken, 200g of anhydrous sodium sulfate is added at about 20 ℃ for salting out, stirred for 30min, filtered and dried to obtain 22.6g of pure dye. |
