Due to the solubility and volatility of rosin, and the fact that it can quickly condense into a "strong and transparent film" after evaporation, painters generally make their own in order to protect the painting and prevent the "sketch" from being rubbed off. The "fixed painting" liquid is: one part rosin powder, nine parts alcohol, or xylene solvent ratio. First put the rosin into a well-sealed glass container, then pour in the alcohol or xylene, and close the lid. It dissolved on its own after two days. To use, shake well and pour into the spray bottle, 20 centimeters away from the screen, spray evenly onto the screen, spray at any time, evaporate at any time, it will dry in a few minutes, and you will not be afraid of being rubbed off in the future. Note: Don’t use too much rosin, otherwise it will turn “yellow and dark”!