Carbonless copy paper is divided into top sheet, middle sheet, and bottom sheet. The next side of the top and middle sheets is coated with a certain medicine, while the upper side of the middle and bottom sheets is coated with another chemical. When combined in the order of top, middle, and bottom sheets, and subjected to the impact force of the print needle or the tip pressure, the two different medicines meet and leave a clear mark, thereby achieving the purpose of copying.