FLUORESCENT PARTICLE, METHOD FOR PREPARING THE SAME AND PAPER FOR PREVENTING FORGERY USING THE FLUORESCENT PARTICLE

WIPO Patent Application WO/2000/039246

A1

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.

MURAKAMI TORU (JP)
ASAI YASUHIKO (JP)
NAKAJIMA TOHRU (JP)
WATANABE YOSHIHIRO (JP)

PCT/JP1999/007208

July 06, 2000

December 22, 1999

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TOKUSHU PAPER MFG CO LTD (JP)
MURAKAMI TORU (JP)
ASAI YASUHIKO (JP)
NAKAJIMA TOHRU (JP)
WATANABE YOSHIHIRO (JP)

B41M5/52; C09C3/10; C09K11/02; C09K11/08; D21H21/30; D21H21/48; D21H27/32; (IPC1-7): C09K11/02; C09K11/06; C09K11/08; C09C3/10; D21H21/48; G07D7/12

EP0692517A1	1996-01-17
JPS5378986A	1978-07-12
JPS5925874A	1984-02-09
JPH02308892A	1990-12-21
JPH04331282A	1992-11-19
JPH05125358A	1993-05-21
JPH0790252A	1995-04-04
JPH10121039A	1998-05-12
JPH066500U	1994-01-28
JPH11200281A	1999-07-27
JPH11323785A	1999-11-26

See also references of EP 1074599A4

Omata, Yukio (4th floor 16-13, Ginza 8-chom, Chuo-ku Tokyo, JP)

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