Dai Nippon Printing Co., Ltd.

Akiko Kitamura

Mitsuru Kitamura

Tsuyoshi Yamauchi

Manabu Yamamoto

Yoko Sekine

Sakurako Hatori

Kenji Ueda

Makio Kurashige

Masachika Watanabe

Tomoko Kumasawa

A light-emitting medium including a light-emitting image having a pattern area formed on a substrate by using a first fluorescent ink containing a first fluorescent material, a background area formed on the substrate by using a second fluorescent ink containing a second fluorescent material, and a overcoat layer formed on the first fluorescent material of the pattern area and the second fluorescent material of the background area. The first fluorescent material is made of a fluorescent material which emits light of blue color when UV-A is irradiated, and emits light of red color when UV-C is irradiated. The second fluorescent material is made of a fluorescent material which emits light of blue color or light of a color that is viewed as the same color as the blue color when the UV-A is irradiated, and emits light of green color when the UV-C is irradiated.

Light-emitting medium

A main object of the present invention is to provide fine particles, a particle group, an anti-counterfeiting ink, an anti-counterfeiting toner, an anti-counterfeiting sheet, and an anti-counterfeiting medium enabling to achieve a high level of authentication. The object of the present invention is achieved by providing the fine particle comprising an identification information group including multiple types of identification information identifiable by magnification, characterized in that the identification information group includes first identification information and second identification information which cannot be identified at any magnifying power capable of identifying the first identification information.

Fine particles, particle group, anti-counterfeiting ink, anti-counterfeiting toner, anti-counterfeiting sheet, and anti-counterfeiting medium

A main object of the invention is to provide a taggant particle group that has a plurality of authentication steps and an excellent anti-counterfeit effect and can be applied to various anti-counterfeit media. The invention attains the object by providing a taggant particle group which is an aggregate of taggant particles which individually have a plurality of identification information items, wherein one identification information item among the plurality of identification information items possessed by the individual particles is common identification information that is possessed in common by the taggant particles that constitute the taggant particle group, and another identification information item among the plurality of identification information items possessed by the individual particles is non-common identification information of which the authenticity can be determined in combination with other identification information items possessed by other taggant particles that constitute the taggant particle group.

Taggant particle group; and anti-counterfeit ink, anti-counterfeit toner, anti-counterfeit sheet, and anti-counterfeit medium comprising same

A light-emitting medium having a light-emitting image including first pattern elements formed on a substrate by using a first fluorescent ink containing a first fluorescent material, and second pattern elements formed on the substrate by using a second fluorescent ink containing a second fluorescent material. The first and second pattern elements form a plurality of micro-character rows m, and the first pattern elements form a latent image in the micro-character rows m. The first fluorescent material is made of a fluorescent material which emits light of blue color when UV-A is irradiated, and emits light of red color when UV-C is irradiated. The second fluorescent material is made of a fluorescent material which emits light of blue color or light of a color that is viewed as the same color as the blue color when the UV-A is irradiated, and emits light of green color when the UV-C is irradiated.

A process by which a multi-image type hologram, wherein one 3D image changes over to another depending on a viewing direction, can be fabricated in a simple construction, and a multi-image type hologram fabricated by that process. According to the process for the fabrication of a multi-image type hologram wherein one image changes over to another depending on a viewing direction, the area of a hologram recording material is divided into a plurality of sub-areas. Objects to be displayed on different images are holographically recorded in the respective sub-areas, using reference light having the same angle of incidence, images recorded in the respective sub-areas are simultaneously reconstructed from the recorded first-stage hologram, so that a second-stage hologram recording material is located near the reconstructed object images for recording them as a reflection or transmission type volume hologram.

Fabrication process of multi-image type hologram, and multi-image type hologram fabricated by that process

A recording plane of a computer-generated hologram that is capable of reconstructing a full-color image and achieving a high resolution is divided by a multiplicity of parallel sections in the horizontal direction to define a multiplicity of areas. Amplitude information and phase information corresponding to different wavelengths which vary periodically in a direction traversing the multiplicity of areas, is recorded in the recording medium. Information about the same portion of the original image is recorded in individual points belonging to the same area, and information about another corresponding portion of the original image is recorded in individual points belonging to another area.

Computer-generated hologram including splice planes for reconstructing a full-color image with high resolution and its fabrication method

There is provided a light-emitting medium by which whether a valuable paper or the like is forged or not can be judged easily and promptly. A light-emitting medium constituting a valuable paper includes a light-emitting image. The light-emitting image is composed of a pattern area formed on a substrate by using a first fluorescent ink containing a first fluorescent material, and a background area formed on the substrate by using a second fluorescent ink containing a second fluorescent material. When UV-A is irradiated, the first fluorescent ink and the second fluorescent ink emit light of colors that are viewed as different colors from each other. In addition, when UV-C is irradiated, the first fluorescent ink and the second fluorescent ink emit light of colors that are viewed as different colors from each other, the colors being different from the colors that are viewed when the UV-A is irradiated.

Light-emitting medium and method of confirming light-emitting medium

A computer-generated hologram that is capable of reconstructing a full-color image and achieving a high resolution is provided. A recording plane of the hologram is divided by a multiplicity of parallel sections in the horizontal direction to define a multiplicity of areas. Amplitude information and phase information corresponding to different wavelengths which vary periodically in a direction traversing the multiplicity of areas, is recorded in the recording medium. Information about the same portion of the original image is recorded in individual points belonging to the same area, and information about another corresponding portion of the original image is recorded in individual points belonging to another area.

Growing community of inventors

Nagareyama, Japan

Akiko Kitamura