US 8,523,238 B2 · Light-emitting medium and method of confirming light-emitting medium

Abstract

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.

Claims23

Dependent claims

A light-emitting medium including a light-emitting image on a substrate,

wherein:
the light-emitting image includes a first area containing a first fluorescent material and a second area containing a second fluorescent material;
when invisible light within a first wavelength range is irradiated, the first fluorescent material and the second fluorescent material emit light of colors that are viewed as different colors from each other;
when invisible light within a second wavelength range is irradiated, the first fluorescent material and the second fluorescent material 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 invisible light within the first wavelength range is irradiated;
and
when the invisible light within the first wavelength range and the invisible light within the second wavelength range are simultaneously irradiated, the first fluorescent material and the second fluorescent material emit light of colors that are viewed as the same color with each other.

3 more elements

A light-emitting medium including a light-emitting image on a substrate,

wherein:
the light-emitting image includes a first area containing a first fluorescent material and a second area containing a second fluorescent material;
when invisible light within a first wavelength range is irradiated, the first fluorescent material and the second fluorescent material emit light of colors that are viewed as different colors from each other;
when invisible light within a second wavelength range is irradiated, the first fluorescent material and the second fluorescent material 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 invisible light within the first wavelength range is irradiated;
the first fluorescent material emits light of a first color when the invisible light within the first wavelength range is irradiated, and emits light of a second color when the invisible light within the second wavelength range is irradiated;
and
the second fluorescent material emits light of the second color or light of a color that is viewed as the same color with the second color when the invisible light within the first wavelength range is irradiated, and emits light of the first color or light of a color that is viewed as the same color with the first color when the invisible light within the second wavelength range is irradiated.

4 more elements

Dependencies are inferred from the claim text.

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

Life of this patent

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

Life of this patent

Abstract

Claims23