What is the principle of carbonless copy paper?

There are two kinds of coatings in carbonless copy paper: CF layer containing color developer and CB layer containing color developer. The chromogenic agent is a special leuco dye, which has been dissolved in a non-volatile carrier oil and encapsulated by 3~7μm microcapsules. The impact pressure of hard writing and printing can crush the microcapsules, so that the leuco dye solution flows out and comes into contact with the color developer, and a chemical reaction occurs to present colored pictures and texts, so as to achieve the purpose of copying. Carbonless copy paper is divided into 45g/m2CB paper, 47g/m2CF paper and 52g/m2CFB paper according to the quantitative point; according to the color of the paper, there are five kinds of red, yellow, green, blue and white; Yellow, orange, black, red and other colors.