| 摘要 |
<p>Fluorescent particles capable of emitting fluorescence strongly upon irradiation with ultraviolet rays which comprises granules prepared by granulating a mixture of a water-insoluble fluorescent dye and/or pigment capable of emitting fluorescence upon irradiation with ultraviolet rays and a powdery substance comprising starch, cellulose, polysaccharide, saccharide and the like, or comprises granules comprising the powdery substance and, formed on the surface of the granules, a coating layer comprising the fluorescent dye and/or pigment; and a method for preparation of the particles. The combined use of a resin having a group reactive with a hydroxyl group of the powdery substance as a binder leads to the preparation of particles excellent in resistance to water. Water-resistant particles can also be prepared by a method of incorporation of an anionic binder into the granules and of a cationic substance into the coating layer, or, incorporation of a cationic binder into the granules and of an anionic substance into the coating layer, through the interaction of the anionic and cationic ingredients incorporated. The fluorescent particles can be used for providing the paper for preventing forgery containing particles which emit fluorescence in a specific hue and become clearly visible upon irradiation with ultraviolet rays.</p> |
