摘要 |
Carbonless copy paper is prepared by placing a first sheet of paper coated on one side with a hydrophilic colloid solution in which are dispersed microcapsules of oil droplets containing a colorless electron donor dye into contact with a second sheet of paper coated with an absorbent and an electron accepting color developer compound. The heat resistance and moisture resistance of the copy paper is substantially improved by adding to the hydrophilic colloid solution a graft copolymer having a backbone of carboxymethyl cellulose or gum arabic and side chains of polyacrylic acid or polymethacrylic acid. The image response time of the second sheet can be improved by adding pectin or sulfated starch to the coating. |