The film forming agent is an important part of the erasable ballpoint pen ink. Its function is to form a uniform film on the surface of the paper and act as a carrier for the dye. It is required to have a certain degree of adhesion to paper, not easy to peel off, but it can be gently wiped off with an eraser, has strong adhesion to the colorant, has good solubility in solvents, and is stable with other ingredients, and can be stored for a long time . In this experiment, rubber film formers were used.
