| Name | synthetic tanning agent DLT-1 |
| Synonyms | PO type synthetic tanning agent DLT-1 synthetic tanning agent Synthetic tanning agent DLT-1 |
| PH | 1.5~2.0 |
| Physical and Chemical Properties | Chemical properties light red viscous liquid, easily soluble in water, has the function of dissolving tannin extract, reducing precipitation and accelerating penetration. |
| Use | Combination tanning of heavy leather. Used for fur tanning. |
| Caution | Irritating, pay attention to protection. Wash immediately with soap and water if it gets on the skin. Do not come into contact with iron products. Place in a cool storage area, avoiding high heat and |
Put 400kg of phenol into the condensation kettle. Heat and melt, add a catalyst amount of sulfuric acid, and start dripping 244kg of 37% formaldehyde aqueous solution at around 65 ℃. After dripping, react at a temperature of 90-95 ℃ for 3-4 hours, then reduce pressure for dehydration. After dehydration, press the material into a sulfonation kettle, and add 79kg of acetic anhydride dropwise at 80-85 ℃ with stirring. Control the reaction temperature below 85 ℃ during the dripping process. After dripping, cool to 70 ℃ and start adding 160kg of concentrated sulfuric acid. After dripping, react at 85-90 ℃ for 4 hours. Dilute with water to the required content to obtain the product.