Design of Sodium alginate/PVA based erasable film with a wide-range adjustable information storage time

Abstract

Abstract Paper manufacturing is frequently associated with severe environmental pollution. The light-responsive rewritable paper has become one of the important research directions to replace traditional paper because of its excellent non-contact writing and pollution-free characteristics. However, the reported information storage time of photoetching paper is short, making application control on various occasions difficult. In this study, ammonium molybdate was used as a photochromic agent in SA/PVA composite films. This film's printing effect and mechanical properties are equivalent to those of current paper, and the clear boundary can still be seen at a magnification of 20 times. Within 50 days, the film can still show visible color with no loss of resolution. Meanwhile, the film can be efficiently decolorized in an aqueous solution using the water-soluble properties of SA and PVA, and then regenerated by simply laying the film. The film quality and resolution did not degrade after ten cycles of "information writing-dissolution erasing-regeneration writing" demonstrating excellent recycling performance. As a result, this study not only achieves long-term storage of the film's information, but also employs a simple and environmentally friendly recycling process to adjust its storage time, thereby providing a new method for the design of photoetching paper.