| Name | fluorescent whitening agent 31# |
| Synonyms | Fluorescent brightener No.31 |
| Molecular Formula | C36H33ClN12Na2O8S2 |
| Molar Mass | 907.30 |
| Physical and Chemical Properties | Chemical quality This product is a light yellow powder, soluble in boiling water or 1,000 times of 25°C water, and the fluorescent tone is blue. Anionic type. Suitable for neutral or slightly alkaline staining. |
| Use | This product is used for cotton strong, nylon, rayon and other whitening, can make the whitened fabric white and bright. Also used for paper, synthetic detergent, soap, soap and other whitening. Used for whitening of synthetic detergent and cotton, silk and other fibers |
Add 1000kg of crushed ice water to the reaction kettle and adjust the pH value with hydrochloric acid until the Congo red test paper turns slightly purple. Then add 136kg of melamine, stir and beat. Additionally, prepare DSD acid into a 10% aqueous solution and adjust the pH to 6-7 with soda ash, then add it to the melamine slurry. Control the pH value between 5 and 6. The reaction ends at the disappearance of the amino group. Add a mixture of 41.5kg m-chloroaniline and 31kg aniline to the first condensation solution. React at 30-35 ℃ for 2 hours, then heat up to 85-95 ℃ for 2 hours until all aniline disappears. Finally, add monoethanolamine at 100 ℃ for the third condensation, and control the pH value to 6-7. Cool and filter to obtain fluorescent whitening agent No. 31. Then, it is mixed with leveling agent and water for sanding, dried, and mixed with sodium sulfate to obtain the finished product.
This product can be managed according to general industrial chemicals. When using it, gloves and protective glasses should be worn to avoid direct contact with the skin and eyes. If it gets on the skin, rinse with water and soap. Place in a cool and dry warehouse to prevent exposure to sunlight and rain.
add 1 000 kg of crushed ice water to the reaction kettle, and adjust the pH value to Congo red test paper with hydrochloric acid to be slightly purple. Then add 136 kg of cyanogen chloride and stir and beat. In addition, DSD acid is prepared into a 10% aqueous solution, and the pH value is adjusted to 6~7 with soda ash. It is then added to the cyanide chloride slurry. The pH value is controlled to be 5~6. The reaction ends with the disappearance of the amino group. A mixture consisting of 41.5kg of m-chloroaniline and 31 kg of aniline was added to the first condensation solution. After reacting at 30~35 ℃ for 2 h, the temperature is raised to 85~95 ℃ for 2 h until aniline disappears. Finally, monoethanolamine was added at 100 ℃ for the third synthesis, and the pH value was controlled to be 6~7. Cool and filter to obtain fluorescent whitening agent 31#. Then it is mixed with levelling agent and water for sanding, and after drying, it is mixed with anhydrine to obtain the finished product.