METHOD FOR REVERSIBLY DEVELOPING COLOR STORING/PHOTOCHROMIC FUNCTION OF WRITING IMAGE AND REVERSIBLE COLOR STORING/PHOTOCHROMIC WRITING UTENSIL

摘要

PPROBLEM TO BE SOLVED: To provide a method for mutually storing and holding a color developing condition and a color erasing condition in a photochromic writing utensil, and a reversible color storing/photochromic writing utensil utilizing the above described method. PSOLUTION: The writing utensil contains a photochromic ink which comprises a photochromic compound with a photo-memory function (color storing/photochromic) and forms a photochromic writing image which develops a color by irradiating with UV rays or the sunlight containing UV rays, and erases the color by irradiating with visible rays to change it to a color erasing condition on the surface of an object. A color converting means which contains a UV absorbing agent and/or a photo-masking pigment for masking at least UV rays, and cut the UV rays in the sunlight, and erases the photochromic compound under a color developing condition by irradiating with the visible light to displace it to a color erasing condition and to keep it, is provided. The color converting means is arranged under a contact or non-contact condition with the photochromic image, and color developing condition and a color erasing condition are reversibly stored and held. PCOPYRIGHT: (C)2005,JPO&NCIPI