冬青油中含水杨酸甲酯（可达98%）。本品为无色至淡黄色或微红色油状液体

Wintergreen oil contains methyl salicylate (up to 98%). This product is colorless to light yellow or reddish oily liquid. There is a special smell of holly. In case of iron, the color becomes darker. Boiling point (simultaneous decomposition) 219 ~ 224 ℃. Soluble in ethanol and glacial acetic acid, the solubility in water is minimal. Add salicylic acid to the reaction kettle, add excess methanol, add catalyst sulfuric acid under stirring, and heat to react. After the reaction is complete, wash with water until neutral. Distillation is carried out first, and methanol and residual water are distilled off under normal pressure, and then the fraction can be collected by distillation under reduced pressure.

Holly oil contains salicylic acid (up to 98%). This product is colorless to pale yellow or slightly red oily liquid. There is a special smell of holly. In the event of a deep erstwon color. Boiling point (simultaneous decomposition) 219 to 224 degrees C. Soluble in ethanol and ice acetic acid, the solubility in water is minimal. Add salicylic acid to the reactor, add excess methanol, stir and then add the catalyst sulfuric acid, heating for reaction. After the reaction is complete, wash with water to neutral. Distillation, first often steamout methanol and residual water, and then de-stress distillation to collect fractions can be.

The Holly oil contains methyl salicylate (up to 98%). This product is colorless to light yellow or reddish oily liquid. It has the special smell of holly. The color turns dark when encountering iron. Boiling point (simultaneous decomposition) 219 ~ 224 ℃. Soluble in ethanol and glacial acetic acid, the solubility in water is very small. Salicylic acid is added to the reactor, and excessive methanol is added. Under stirring, sulfuric acid is added to the catalyst, and the reaction is carried out by heating. After reaction, wash with water to neutral. Then carry on the distillation, the first atmospheric distillation of methanol and residual water, and then vacuum distillation to collect the fraction.<br>