WO2018186324A1 - Latent image aqueous ink composition, usage method and printed object thereof, printed object of solid preparation, and method for printing solid preparation - Google Patents

Abstract

Provided are: a latent image aqueous ink composition, where a latent image obtained thereby has suppressed visibility in the visible light region, and the aqueous ink composition is capable of developing the latent image after irradiation with ultraviolet rays; and a usage method and printing object thereof. This latent image aqueous ink composition is optically transparent in the visible light region and is used for printing a latent image, wherein: the latent image aqueous ink composition includes at least a fluorescent agent that emits fluorescence in the visible light region due to irradiation with ultraviolet rays having a wavelength region in the range of 100-400 nm; the fluorescent agent is at least one selected from the group consisting of riboflavin, a riboflavin butyric acid ester, a riboflavin sodium phosphate ester, a cinnamic acid derivative, L-tryptophan, tyrosine, phenylalanine, quinine, quinine hydrochloride dihydrate, quinine sulfate, red no. 3, red no. 104, red no. 105, red no. 106, fumaric acid, chlorophyll, and rhodamine; and the fluorescent agent content is within a range of 0.001-10% by mass relative to the total mass of the latent image aqueous ink composition.

Description

Aqueous ink composition for latent image, method of use and printed matter, and printed matter of solid formulation and printing method of solid formulation

The present invention relates to an aqueous ink composition for a latent image, a method of use, and a printed material. More specifically, for example, on a recording medium such as a pharmaceutical, an image that is a latent image in the visible light region and is visualized after ultraviolet irradiation. It is related with the aqueous ink composition for latent images which can print, and a usage method and printed matter.

The present invention also relates to a printed matter of a solid preparation and a printing method of the solid preparation, and more specifically, to a solid preparation such as a pharmaceutical or food, a latent image that can be visualized by ultraviolet irradiation, and under visible light irradiation. The present invention relates to a printed matter of a solid preparation on which a visible image that can be visually recognized is printed, and a printing method of the solid preparation.

In recent years, concerns have increased that counterfeit pharmaceutical products (counterfeit drugs) have become widespread. Counterfeit products not only exacerbate the profits of authorized manufacturers, but also pose a health hazard to consumers who buy without knowing that they are counterfeit products. For this reason, it is necessary to prevent counterfeit pharmaceutical products from entering the market.

On the other hand, for pharmaceutical products such as tablets and capsules, product information is directly printed by stamp printing, stamp printing, ink jet printing, etc., so that the product information of the pharmaceutical products can be visually confirmed to the user. For example, in an edible ink-jet ink composition that can be directly printed on a tablet having an orally disintegrating property, Patent Document 1 uses a squid ink pigment composed of particles having a particle size of 10 nm or more and 1 μm or less as a food pigment. It is disclosed. Patent Document 2 discloses that the edible inkjet ink composition uses a synthetic dye aluminum lake as a food dye. Further, Patent Document 3 discloses that a water-soluble ink composed only of a dye-based food coloring is used to print an image on the surface of a solid preparation.

However, when product information is printed on tablets or the like using these edible ink-jet ink compositions, anyone can view the product information, so counterfeiters print the same product information on counterfeit products. It becomes possible to do. As a result, the printing of product information using conventional edible inkjet ink compositions facilitates the production of counterfeit products that are difficult to confirm as genuine. In addition, in known optical reading methods such as OCR, OMR, barcode, and two-dimensional code, since the code is visible as a printed image line, there is a risk of decoding and tampering, and it is used as a measure for preventing forgery and alteration. Is not enough. On the other hand, the product information includes information that can be visually recognized by general users.

Japanese Patent Laying-Open No. 2015-81315 JP 2012-111824 A Japanese Patent Laying-Open No. 2015-3883

The present invention has been made in view of the above-mentioned problems, and a first object thereof is a latent image in which visibility is suppressed under a visible light region, and the latent image is visualized after ultraviolet irradiation. It is an object to provide a latent aqueous ink composition for latent images, a method of use, and a printed matter.

In addition, the second object of the present invention is a latent image that is difficult to visually recognize under irradiation with visible light and can be visualized by irradiation with ultraviolet light, and a visible image that is visible under irradiation with visible light. It is providing the printed matter of a solid formulation which has these, and the printing method of a solid formulation.

The aqueous ink composition for a latent image according to the present invention is an aqueous ink composition for a latent image for printing a latent image, having light transmittance in a visible light region, in order to solve the above-described problems. At least a fluorescent agent that emits fluorescence in the visible light region when irradiated with ultraviolet rays having a wavelength range of 100 nm to 400 nm, and the fluorescent agent is riboflavin, riboflavin butyrate, sodium riboflavin phosphate, cinnamic acid derivative, L-tryptophan , Tyrosine, phenylalanine, quinine, quinine hydrochloride dihydrate, quinine sulfate, red 3, red 104, red 105, red 106, at least one selected from the group consisting of fumarate, chlorophyll and rhodamine The content of the fluorescent agent is 0.001% by mass to 10% by mass with respect to the total mass of the aqueous ink composition for latent images. Characterized in that it is in the range of.

Since the aqueous ink composition for latent images having the above structure (hereinafter sometimes referred to as “aqueous ink composition”) has light transmittance in the visible light region, the aqueous ink composition is used. For example, when printing is performed using an inkjet method, it is possible to print a latent image that is difficult to view under the visible light region. On the other hand, since the water-based ink composition having the above-described structure contains a fluorescent agent that emits fluorescence when irradiated with ultraviolet rays in a wavelength region of 100 nm to 400 nm, a printed image composed of a latent image is irradiated with light containing ultraviolet rays in the wavelength region. Can visualize the printed image under a visible light region.

In the above-described configuration, the content of the fluorescent agent is 0.001% by mass to 10% by mass or less with respect to the total mass of the aqueous ink composition. Thereby, in the said structure, a latent image can be printed, maintaining the light transmittance in visible region. In addition, it is possible to prevent the solubility of the fluorescent agent in the aqueous ink composition from being excessively lowered, to maintain the ejection stability from the ink jet nozzles well, and to prevent the flying performance from being lowered.

In the above-described configuration, it is preferable that the aqueous ink composition for a latent image is used for printing a latent image by an inkjet method on a solid preparation, and the fluorescent agent is edible. The water-based ink composition of the present invention makes it possible to print a latent image that can be visualized by irradiation with ultraviolet rays in the wavelength range. Therefore, when a solid preparation is used as a recording medium and product information is printed as a latent image on the recording medium, it becomes difficult to visually recognize the product information etc. under the visible light region, thus suppressing the production of counterfeit products. Can do. When it is desired to confirm an image such as product information printed as a latent image or to confirm the authenticity of a product, this can be visualized by irradiating the printed image including the latent image with ultraviolet rays. .

Further, in order to solve the above-mentioned problems, the method for using the latent image aqueous ink according to the present invention uses a latent image aqueous ink containing a latent image aqueous ink composition to form a latent image on a recording medium. A method of using a latent ink for printing a latent image, wherein the surface of the recording medium has a light-transmitting property with respect to visible light and is irradiated with ultraviolet rays having a wavelength range of 100 nm to 400 nm. A latent image printing step of forming a latent image ink layer that emits fluorescence and irradiating the latent image ink layer with light containing ultraviolet rays in a wavelength region of at least 100 nm to 400 nm, The latent image ink layer generates fluorescence in the visible light region and visualizes the latent image, and the latent image water-based ink composition has a wavelength range of 100 nm to 400 nm. Visible light by UV irradiation A fluorescent agent that emits fluorescence in the region, and the fluorescent agent is riboflavin, riboflavin butyrate ester, sodium riboflavin phosphate ester, cinnamic acid derivative, L-tryptophan, tyrosine, phenylalanine, quinine, quinine hydrochloride dihydrate, Quinine sulfate, Red No. 3, Red No. 104, Red No. 105, Red No. 106, at least one selected from the group consisting of fumarate, chlorophyll and rhodamine, and the content of the fluorescent agent is an aqueous ink for latent images A composition having a composition in the range of 0.001% by mass to 10% by mass with respect to the total mass of the composition is used.

According to the above-described configuration, the latent image water-based ink (hereinafter sometimes referred to as “water-based ink”) includes the water-based ink composition having light transmittance in the visible light region. In addition, it is possible to print a latent image ink layer including a latent image that is difficult to visually recognize in the visible light region. Further, since the aqueous ink composition contains a fluorescent agent that emits fluorescence when irradiated with ultraviolet rays in a wavelength range of 100 nm to 400 nm, in the visualization step, the latent image ink layer contains light containing at least ultraviolet rays in the wavelength range. , The latent image can be visualized (visualized) in the visible light region.

In the above configuration, a solid preparation can be used as the recording medium. The method of use of the present invention includes a step of printing a latent image that can be visualized by irradiation with ultraviolet rays in the wavelength range. Therefore, when a solid preparation is used as a recording medium and product information is printed as a latent image on the recording medium, it becomes difficult to visually recognize the product information etc. under the visible light region, thus suppressing the production of counterfeit products. Can do. If you want to check the product information image printed as a latent image, or if you want to check the authenticity of the product, you can visualize this by irradiating the printed image containing the latent image with ultraviolet rays. it can.

In order to solve the above problems, the printed material according to the present invention is a printed material in which a latent image is provided on at least a part of the surface of the recording medium, and the latent image is light transmissive to visible light. And a latent image ink layer that emits fluorescence in the visible light region when irradiated with ultraviolet rays having a wavelength range of 100 nm to 400 nm, and the latent image ink layer is riboflavin, riboflavin butyrate, sodium riboflavin phosphate Cinnamic acid derivatives, L-tryptophan, tyrosine, phenylalanine, quinine, quinine hydrochloride dihydrate, quinine sulfate, red 3, red 104, red 105, red 106, fumarate, chlorophyll and rhodamine It includes at least one fluorescent agent selected from the group consisting of:

According to the above configuration, the latent image ink layer provided on the recording medium has light transmittance under the visible light region and includes a latent image. Can be difficult. Since the latent image ink layer contains a fluorescent agent capable of emitting fluorescence when irradiated with ultraviolet rays in a wavelength range of 100 nm to 400 nm, the printed matter having the above structure is irradiated with light containing the ultraviolet rays. By generating fluorescence in the latent image ink layer, the latent image ink layer including the latent image can be visualized.

In the above configuration, the recording medium can be a solid preparation. As a result, when product information is printed with a latent image ink layer containing a latent image, it is difficult to visually recognize under the visible light region, so that it is possible to make it difficult to manufacture a counterfeit product on which the product information is printed. . In addition, the product information formed by the latent image ink layer can be easily visualized by irradiating the latent image ink layer with ultraviolet rays, so the printed product information can be confirmed and dispensing errors can occur. Can be suppressed, and the authenticity of the product can be confirmed.

Further, in order to solve the above problems, a printed matter of a solid preparation according to the present invention is a printed matter of a solid preparation in which a latent image and a visible image are provided on at least a part of the surface. Consists of a latent image ink layer that is transparent to visible light and emits fluorescence in the visible light region when irradiated with ultraviolet light in the wavelength range of 100 nm to 400 nm. The visible image is visible under visible light irradiation. It consists of a possible visible ink layer.

According to the above configuration, a latent image composed of the latent image ink layer and a visible image composed of the visible ink layer are provided on at least a part of the surface of the solid preparation. Since the latent image ink layer has a light-transmitting property with respect to visible light, it is difficult to visually recognize the latent image made of the latent image ink layer under irradiation of visible light. Further, since the latent image ink layer emits fluorescence in the visible light region when irradiated with ultraviolet rays in a wavelength range of 100 nm to 400 nm, the latent image formed of the latent image ink layer is visualized (visualized) under the irradiation of the ultraviolet rays, It can be visually recognized well. On the other hand, since the visible ink layer can be viewed under irradiation with visible light, a visible image made of the visible ink layer can be viewed well under irradiation with visible light. Therefore, when the solid preparation is a printed matter having the above-described configuration, it becomes possible to record information on the surface of the solid preparation as a latent image or a visible image according to the content of the information, and the degree of freedom of the information recording method is improved. be able to.

In the above configuration, the latent image ink layer is composed of riboflavin, riboflavin butyrate ester, sodium riboflavin phosphate ester, cinnamic acid derivative, L-tryptophan, tyrosine, phenylalanine, quinine, quinine hydrochloride dihydrate, quinine sulfate, It is preferable to include at least one fluorescent agent selected from the group consisting of Red No. 3, Red No. 104, Red No. 105, Red No. 106, fumarate, chlorophyll and rhodamine.

Further, in the above configuration, the latent image ink layer is formed of a dry film of a latent image aqueous ink, and the latent image aqueous ink includes the latent image aqueous ink composition containing the fluorescent agent. The content of the fluorescent agent is preferably in the range of 0.001% by mass to 10% by mass with respect to the total mass of the aqueous coating composition.

According to the above configuration, the latent image ink layer is made of a dry film of the water-based ink printed using the latent image water-based ink (hereinafter sometimes referred to as “water-based ink”). Can do. In the aqueous ink composition for latent images contained in the aqueous ink (hereinafter sometimes referred to as “aqueous ink composition”), the fluorescent agent is added in an amount of 0.001 mass relative to the total mass of the aqueous ink composition. Since it is contained in the range of 10% to 10% by weight, it is possible to print a latent image while maintaining light transmittance in the visible light region. In addition, since the solubility of the fluorescent agent in the aqueous ink composition is prevented from excessively decreasing, for example, when printing a latent image ink layer by an inkjet method, the ejection stability from the inkjet nozzle is improved. It can maintain and can suppress that flying property falls.

Further, in the above-described configuration, the visible ink layer and the latent image ink layer may be provided in different regions on the surface, or may be sequentially stacked on the surface at least partially overlapping each other. When the latent image ink layer and the visible ink layer are formed in different regions on the surface of the solid preparation, the latent image visualized by the irradiation of the ultraviolet ray and the visible image are visually recognized. Can be prevented. In addition, when the latent image ink layer and the visible ink layer are laminated in a state where at least part of them overlap, more information can be obtained even when the area of the printable region on the solid preparation is small. Can be recorded.

In the case where the visible ink layer and the latent image ink layer are laminated in a state where at least a part thereof overlaps, the latent image ink layer is laminated on the visible ink layer. As a result, the entire area of the latent image ink layer can be irradiated with ultraviolet rays at the time of visualization by irradiation with the ultraviolet rays, and the latent image can be visualized in a good state. In addition, since the latent image ink layer has light transmittance in the visible light region, it is possible to suppress a reduction in the visibility of the visible image under visible light irradiation.

Further, the solid preparation printing method according to the present invention is a solid preparation printing method for printing a latent image and a visible image on at least a part of the surface of the solid preparation in order to solve the above-mentioned problems, On the surface of the solid preparation, a visible ink layer that is visible under irradiation with visible light is printed to form the visible image, a visible image printing region, a region different from the visible image printing region, An area that is different from the area to be printed or an area that at least partially overlaps the visible image printing area has optical transparency to visible light and is visible by irradiation with ultraviolet rays having a wavelength range of 100 nm to 400 nm. A latent image printing step of printing a latent image ink layer that emits fluorescence in the light region to form the latent image.

According to the above configuration, in the visible image printing step, the visible ink layer that is visible under visible light irradiation is printed on the surface of the solid preparation, thereby forming a visible image. Further, in the latent image printing step, the latent image ink has a light-transmitting property with respect to visible light on the surface of the solid preparation and emits fluorescence in the visible light region when irradiated with ultraviolet rays having a wavelength range of 100 nm to 400 nm. Form a layer. Thereby, it is difficult to visually recognize under irradiation of visible light, and a latent image that can be visualized by emitting fluorescence can be formed under irradiation of ultraviolet rays in the wavelength range.

Here, when printing of the latent image ink layer in the latent image printing step is performed in an area different from the print area of the visible image or an area different from the print scheduled area of the visible image, the latent image ink layer is exposed by the irradiation of the ultraviolet rays. It is possible to prevent the visualized latent image and the visible image from being visually recognized. In addition, when the latent image ink layer is printed in an area at least partially overlapping the print area of the visible image, more information is obtained when the area of the printable area on the solid preparation is small. Can be recorded on the formulation surface. Note that when the latent image ink layer is printed in an area at least partially overlapping the visible image print area, the latent image ink layer is printed so as to be partially laminated on the visible ink layer. As a result, the entire area of the latent image ink layer can be irradiated with ultraviolet rays at the time of visualization by irradiation with the ultraviolet rays, and the latent image can be visualized in a good state. In addition, since the latent image ink layer has light transmittance in the visible light region, it is possible to suppress a reduction in the visibility of the visible image under visible light irradiation.

Further, in the above configuration, the latent image printing step is a step of printing the latent image ink layer by an inkjet method using a latent image aqueous ink containing a latent image aqueous ink composition, The aqueous ink composition for latent images contains a fluorescent agent that emits fluorescence in the visible light region when irradiated with ultraviolet rays having a wavelength range of 100 nm to 400 nm, and has light transmittance in the visible light region. preferable. As a latent image aqueous ink for printing a latent image ink layer, by using a latent image water-based ink composition having light transmittance in the visible light region, the latent image ink layer can be visually recognized under irradiation with visible light. A difficult latent image ink layer can be formed. Also, a latent image ink layer that can be visualized by generating fluorescence in the visible light region upon irradiation with the ultraviolet rays is formed by using the aqueous ink composition for latent images containing the fluorescent agent. can do.

In the above structure, the fluorescent agent includes riboflavin, riboflavin butyrate ester, sodium riboflavin phosphate ester, cinnamic acid derivative, L-tryptophan, tyrosine, phenylalanine, quinine, quinine hydrochloride dihydrate, quinine sulfate, It is preferable to use at least one selected from the group consisting of Red No. 3, Red No. 104, Red No. 105, Red No. 106, fumarate, chlorophyll and rhodamine.

In the above configuration, the content of the fluorescent agent is preferably 0.001% by mass to 10% by mass with respect to the total mass of the latent image water-based ink composition.

By using a water-based ink containing a fluorescent agent in the range of 0.001% by mass to 10% by mass with respect to the total mass of the aqueous ink composition for latent images, light transmittance in the visible light region is maintained. It becomes possible to print the latent image. In addition, the solubility of the fluorescent agent in the latent ink composition for the latent image is prevented from excessively decreasing, and the ejection stability from the ink jet nozzle is well maintained, and the flying property is suppressed from decreasing. Can do.

The aqueous ink composition for latent images of the present invention contains a fluorescent agent that has optical transparency in the visible light region and emits fluorescence when irradiated with ultraviolet rays having a wavelength region of 100 nm to 400 nm. Therefore, for example, when the aqueous ink composition for latent images of the present invention is used for printing in an ink jet system, it is difficult to visually recognize under the visible light region, and emits fluorescence after being irradiated with the ultraviolet rays. Thus, a latent image that can be visualized can be printed as a print image. Thereby, for example, when the aqueous ink composition for latent images of the present invention is used for printing product information on a solid preparation, it becomes possible to prevent the production of counterfeit products. In addition, if you want to check the product information, etc. to make preparations, or if you want to check the authenticity of the product, print images can be easily visualized by irradiating light containing ultraviolet rays in the wavelength range of at least 100 nm to 400 nm. There is an effect that can be done.

In addition, according to the printed matter of the solid preparation of the present invention, a visible image composed of a visible ink layer that is visible under irradiation with visible light, light transmittance with respect to visible light, and a wavelength range of 100 nm to 400 nm. A configuration having a latent image composed of a latent image ink layer that emits fluorescence in the visible light region when irradiated with ultraviolet rays in a range is employed. For this reason, for example, product information that can be visually recognized is printed as a visible image, and product information necessary for confirmation of preparation or product authenticity is printed as a latent image. It is possible to provide a printed matter of a solid preparation with an improved degree of freedom.

Furthermore, according to the method for printing a solid preparation of the present invention, it is possible to record information on the surface of the solid preparation, depending on the content of the information, etc., while properly using the latent image or visible image. It is possible to provide a method for printing a solid preparation capable of improving the degree of freedom.

[Embodiment 1]
(Latent image water-based ink composition and latent image water-based ink)
The latent image aqueous ink composition according to Embodiment 1 will be described below.
The aqueous ink composition for latent images of the first embodiment is a composition containing at least a fluorescent agent and using water as a main solvent. In addition, the latent image aqueous ink composition of the first embodiment has edible properties by using a material that complies with the standards of pharmaceutical additives, Japanese Pharmacopoeia or Food Additives specified by the Pharmaceutical Affairs Law. And can be suitably used for recording an image or the like by an inkjet method.

As used herein, “edible” means a substance that is approved for oral administration as a pharmaceutical product or pharmaceutical additive and / or a food product or food additive. Further, in this specification, the “inkjet method” means that a latent image aqueous ink containing a latent image aqueous ink composition is ejected as droplets from a fine inkjet head, and the droplets are fixed on a recording medium. Means a method of forming an image. Details of the recording medium will be described later.

The latent ink composition for latent images preferably has a light transmittance in the visible light region (400 nm to 760 nm). As a result, when the latent image ink layer is formed using the latent image aqueous ink containing the latent image aqueous ink composition, the latent image ink layer can be provided with a light-transmitting property with respect to visible light. . The light transmittance of the latent ink composition for a latent image may be colored as well as colorless. In the present specification, “light-transmitting” means a property of transmitting at least a part of incident visible light.

The fluorescent agent is a component that, when irradiated with ultraviolet rays (excitation light) having a wavelength range of 100 nm to 400 nm, absorbs the ultraviolet rays and converts the wavelength into the visible light range (380 nm to 760 nm) to emit fluorescence. Specifically, for example, vitamin B group such as riboflavin, riboflavin butyrate and sodium riboflavin phosphate; cinnamic acid derivatives such as methyl cinnamate and ethyl cinnamate; amino acids such as L-tryptophan, tyrosine and phenylalanine; quinine Quinine hydrochlorides such as quinine hydrochloride dihydrate and quinine sulfate; colored fluorescent dyes such as red 3, red 104, red 105 and red 106; fumarate such as disodium fumarate and monosodium fumarate Acid (alkali metal) salts; basic dyes such as chlorophyll and rhodamine, beeswax etc. . These fluorescent agents can be used alone or in combination of two or more.

Among the fluorescent agents listed above, methyl cinnamate, ethyl cinnamate, L-tryptophan, tyrosine, phenylalanine, and fumaric acid (alkali metal) salts are colorless and transparent, and other fluorescent agents are colored and transparent.

Among the fluorescent agents listed above, riboflavin phosphate sodium, red No. 3, red No. 104, red 106 from the viewpoint of improving visibility when fluorescence is generated and visualized. No. is preferred. From the standpoint of ensuring good ejection performance from the inkjet head, riboflavin, riboflavin phosphate sodium ester, L-tryptophan, red No. 104, and red No. 106 are preferable.

In this specification, “fluorescence” includes visible light emitted from the fluorescent agent during the ultraviolet irradiation, and visible light having a short decay time among the afterglow emitted from the fluorescent agent even after the ultraviolet irradiation is completed. Meaning. The decay time means the time required for the transition from the start of light emission of the fluorescent agent to the return to the ground state (fluorescence disappears).

In addition, when the latent ink composition for latent images of the present embodiment is used for printing on a solid preparation, the fluorescent agent is preferably edible. Further, from the viewpoint of visualizing the printed image by visualizing the latent image ink layer, it is preferable that the fluorescent agent has a relatively long decay time and has a luminous property. Thereby, even after the end of ultraviolet irradiation, the visibility of the visualized printed image can be improved by confirming the afterglow emitted by the fluorescent agent.

When the fluorescent agent is colorless and transparent, the content of the fluorescent agent is preferably 0.001% by mass to 10% by mass with respect to the total mass of the latent ink aqueous ink composition. More preferably, it is within the range of 2% by mass to 2% by mass. Further, when the fluorescent agent is colored and transparent, it is preferably 0.001% by mass to 10% by mass, and preferably 0.01% by mass to 1% by mass with respect to the total mass of the latent image aqueous ink composition. More preferably within the range. By setting the content of the fluorescent agent to 10% by mass or less, it is possible to make it difficult to visually recognize an image printed as a latent image. On the other hand, by setting the content of the fluorescent agent to 0.001% by mass or more, it is possible to prevent the latent image ink layer from becoming difficult to visually recognize even after the ultraviolet irradiation. In addition, the content of the fluorescent agent is within the numerical range, considering the visibility of the printed image when the latent image ink layer is formed, the visibility of the latent image ink layer when the fluorescence is generated, and the like. It is preferable to set for each type of fluorescent agent mentioned above.

In the latent image aqueous ink composition of the present embodiment, a dye that does not emit fluorescence may be blended. Examples of such dyes include azo dyes and triphenylmethane dyes. The azo dye is not particularly limited, and examples thereof include Red No. 102, Red No. 40, Yellow No. 4, Yellow No. 5, and the like. The triphenylmethane dye is not particularly limited, and examples thereof include blue No. 1 and green No. 3. Furthermore, it is also possible to use edible natural pigments such as cochineal pigment, copper chlorophyllin sodium, cacao pigment and caramel pigment together. These dyes comply with the standards of pharmaceutical additives, Japanese pharmacopoeia or official food additives specified by the Pharmaceutical Affairs Law, and can be appropriately selected according to the use.

Further, in the aqueous image composition for latent images of the present embodiment, other additives may be blended. Examples of other additives include surface tension adjusting agents, wetting agents, water-soluble resins, organic amines, surfactants, pH adjusting agents, chelating agents, preservatives, viscosity adjusting agents, and antifoaming agents. When the aqueous ink composition for latent images of the present embodiment is used for printing on the surface of solid preparations such as food preparations and pharmaceutical preparations, these other additives are pharmaceutical additives specified by the Pharmaceutical Affairs Law, Japan Pharmacy It is preferable that it complies with the standard of the method or food additive official standard. In addition, the content of these additives is not particularly limited except for the surface tension adjusting agent and the wetting agent, and can be appropriately set as necessary (for the contents of the surface tension adjusting agent and the wetting agent, respectively. (It will be described later.)

The surface tension adjusting agent is not particularly limited, and specific examples include glycerin fatty acid esters and polyglycerin fatty acid esters. Examples of the glycerin fatty acid ester include caprylic acid decaglyceryl, lauric acid hexaglycerin ester, oleic acid hexaglycerin ester, condensed linolenic acid tetraglycerin ester, fatty acid ester palm palm, lauric acid decaglyceryl having an HLB of 15 or less, and HLB. Examples include decaglyceryl oleate of less than 13. You may use these individually by 1 type or in mixture of 2 or more types. In addition, since all of the exemplified surface tension adjusting agents conform to standards such as the Pharmaceutical Affairs Law, they can be applied to printing on solid preparations.

As the caprylic acid decaglyceryl, it is possible to use a commercially available product. Examples of such a commercially available product include Ryoto (registered trademark) polyglycerate CE19D (trade name, manufactured by Mitsubishi Chemical Foods Co., Ltd., HLB). Value 15), SY glister MCA750 (trade name, manufactured by Sakamoto Pharmaceutical Co., Ltd., HLB value 16), and the like.

The HLB value is an HLB value according to the Griffin method and means a value obtained by the following equation.
HLB value = 20 × (sum of formula weight of hydrophilic group / molecular weight)
The HLB value is a value in the range of 0 to 20. The larger the HLB value, the stronger the hydrophilicity, and the smaller the HLB value, the stronger the hydrophobicity.

As the decaglyceryl laurate, those having an HLB of 15 or less can be used. When the decaglyceryl laurate has an HLB of more than 15, the ejection stability is lowered, for example, the occurrence of fading due to clogging of the nozzles of the inkjet head. The lower limit of HLB is preferably 10 or more from the viewpoint of solubility in an aqueous solvent. Further, as decaglyceryl laurate having an HLB of 15 or less, a commercially available product can be used. Examples of such a commercially available product include NIKKOL (registered trademark) DECAGLYN 1-L (trade name, Nikko Chemicals ( HLB value 14.5), SY Glister ML-750 (trade name, manufactured by Sakamoto Pharmaceutical Co., Ltd., HLB value 14.8), and the like.

As the decaglyceryl oleate, those having an HLB of less than 13 can be used. When the HLB is 13 or more, the ejection stability is deteriorated, such as blurring due to clogging of the nozzles of the inkjet head. In addition, it is preferable that the minimum of HLB is 10 or more from a viewpoint of the solubility with respect to a water solvent. Further, as decaglyceryl oleate having an HLB of less than 13, a commercially available product can be used. Examples of such a commercially available product include NIKKOL (registered trademark) DECAGLYN 1-OV (trade name, Nikko Chemicals ( Co., Ltd., HLB value 12), SY Glister MO-7S (trade name, manufactured by Sakamoto Pharmaceutical Co., Ltd., HLB value 12.9), and the like.

As the lauric acid hexaglycerin ester, a commercially available product can be used, and as such a commercially available product, for example, NIKKOL (registered trademark) HEXAGLYN 1-L (trade name, manufactured by Nikko Chemicals Co., Ltd., HLB) Value 14.5), SY Glister ML-500 (trade name, manufactured by Sakamoto Pharmaceutical Co., Ltd., HLB value 13.5), and the like.

Commercially available products can be used as the oleic acid hexaglycerin ester. Examples of such commercially available products include SY Glyster MO-5S (trade name, manufactured by Sakamoto Pharmaceutical Co., Ltd., HLB value 11. 6) and the like.

Commercially available products can be used as the condensed linolenic acid tetraglycerin ester. Examples of such commercially available products include SY Glyster CR-310 (trade name, manufactured by Sakamoto Pharmaceutical Co., Ltd.). It is done.

As the fatty acid ester palm palm, a commercially available product can be used, and examples of such a commercially available product include Tirabazole W-01 (trade name, manufactured by Taiyo Kagaku Co., Ltd.).

The content of the surface tension adjusting agent is preferably within a range of 0.1% by mass to 5% by mass with respect to the total mass of the aqueous ink composition for latent images, and within a range of 1% by mass to 2% by mass. It is more preferable that When the content of the surface tension adjusting agent is 0.1% by mass or more, when printing is performed by an inkjet method, ejection failure due to meniscus formation failure or the like at the nozzle in the inkjet head is prevented, and the nozzle is clogged. Can be prevented. As a result, the discharge stability can be improved. On the other hand, when the content of the surface tension adjusting agent is 5% by mass or less, it is possible to prevent an adverse effect on discharge due to insoluble matter or poor emulsification of the surface tension adjusting agent.

The wetting agent is not particularly limited, and specific examples include polyethylene glycol, propylene glycol, glycerin and the like. In addition, since these wetting agents meet standards such as the Pharmaceutical Affairs Law, they can also be applied to printing on solid preparations.

The amount of the wetting agent added is preferably 1% by mass to 50% by mass, and more preferably 10% by mass to 40% by mass with respect to the total mass of the latent image aqueous ink composition. By setting the content of the wetting agent to 1% by mass or more, clogging in the vicinity of the nozzle of the inkjet head can be prevented, and the ejection performance can be further improved. On the other hand, by setting the content of the wetting agent to 50% by mass or less, the viscosity of the latent image aqueous ink composition can be appropriately controlled.

The latent image aqueous ink composition of the present embodiment contains water (water as a main solvent). As the water, it is preferable to use water from which ionic impurities such as ion-exchanged water, ultrafiltered water, reverse osmosis water, distilled water, or ultrapure water have been removed. In particular, water sterilized by ultraviolet irradiation or addition of hydrogen peroxide is preferable because generation of mold and bacteria can be prevented over a long period of time. Moreover, it does not specifically limit as content of water, It can set suitably as needed.

The viscosity of the latent ink composition for a latent image is preferably 2 mPa · s to 6 mPa · s, more preferably 3 mPa · s to 5 mPa · s at the time of ink jet nozzle ejection, in consideration of ejection stability from the ink jet nozzle. By setting the viscosity of the aqueous ink composition for latent images within the above-mentioned numerical range, it is possible to suppress clogging at the ink jet nozzle and maintain good ejection stability, and to suppress a decrease in flying performance. can do. The viscosity of the latent image water-based ink composition is obtained, for example, by measuring the viscosity at a measurement temperature of 25 ° C. using a viscometer (trade name: VISCOMATE MODEL VM-10A, manufactured by Seconic Corporation). It is done.

The aqueous ink composition for latent images of the present embodiment can be produced by mixing the above-described components by an appropriate method. The mixing method and the order of addition are not particularly limited. After mixing, the mixture is sufficiently stirred, and if necessary, filtration is performed to remove coarse particles and foreign matters that cause clogging. Thereby, the aqueous ink composition for latent images according to the present embodiment can be obtained.

The mixing method of each material is not particularly limited, and for example, the materials can be sequentially added to a container equipped with a stirring device such as a disper, a mechanical stirrer, or a magnetic stirrer to perform stirring and mixing. Moreover, it does not specifically limit as a filtration method, For example, centrifugal filtration, filter filtration, etc. are employable.

The storage of the latent ink for a latent image is preferably performed using a light-shielding container capable of shielding at least ultraviolet rays (wavelength range of 100 nm to 400 nm). This suppresses photodegradation of the fluorescent agent in the aqueous ink composition for latent images, and can be stored for a long period of time. The light-shielding container is not particularly limited, and a conventionally known container such as an aluminum container, a colored container, or a synthetic resin container containing an ultraviolet absorber can be used.

The latent image aqueous ink of the present embodiment includes at least the above-described latent image aqueous ink composition. In particular, when using a latent ink for a latent image containing a pharmaceutical additive stipulated by the Pharmaceutical Affairs Law, a fluorescent agent that conforms to the standards of the Japanese Pharmacopoeia or the Food Additives Standard, etc. Since the water-based ink is edible, it can be directly printed on the surface of a solid agent comprising tablets or capsules such as pharmaceuticals or supplements. In addition, non-contact printing by an ink jet method is possible even for tablets with poor surface smoothness such as uncoated tablets and OD tablets. The method for storing the latent image water-based ink is the same as that of the above-described latent image water-based ink composition.

(Usage method of aqueous ink for latent image)
The method of using the latent ink for latent image according to the first embodiment includes a printing process for printing a latent image ink layer including a latent image, and irradiating the latent image ink layer with ultraviolet rays to visualize (visualize) the latent image. At least a visualization step.

The printing process of the latent image ink layer is a process of printing and forming the latent image ink layer on the recording medium by an ink jet method. More specifically, the latent image aqueous ink containing the latent image aqueous ink composition is ejected as droplets from a fine nozzle, and the droplets are deposited on a recording medium. There are no particular limitations on the method of discharging the latent image water-based ink. For example, a known method such as a continuous ejection type (charge control type, spray type, etc.), on-demand type (piezo type, thermal type, electrostatic suction type, etc.) Can be adopted. Printing conditions such as ink droplet ejection amount and printing speed are not particularly limited, and can be set as necessary.

In addition, the printing process includes a drying process for drying ink droplets attached to the surface of the solid preparation. It does not specifically limit as a drying method, In addition to hot air drying, natural drying etc. can be performed. Also, the drying conditions such as drying time and drying temperature are not particularly limited, and can be appropriately set according to the ejection amount of ink droplets, the type of the latent image aqueous ink composition, and the like.

The latent image visualization step is a step that enables visualization of a printed image by irradiating the latent image ink layer printed in the printing step with light containing ultraviolet rays in a wavelength region of at least 100 nm to 400 nm. is there. When irradiated with ultraviolet rays, the fluorescent agent uniformly contained in the latent image ink layer absorbs the ultraviolet rays and emits (fluoresces) light in the visible light region (380 nm to 760 nm). Thereby, the entire latent image ink layer in which the fluorescent agent is present emits fluorescence and is visualized.

Here, when the latent image ink layer before ultraviolet irradiation is colorless and transparent in the visible light region, the latent image ink layer can be visualized by fluorescence. In addition, fluorescent dyes (red No. 3, red No. 104, red No. 105 or red No. 106) and basic dyes (chlorophyll or rhodamine) are used as fluorescent agents, and the latent image ink layer before UV irradiation is colored in the visible light region. When it is transparent, the visibility is further improved by the fluorescence of the latent image ink layer.

Irradiation light used for visualization of the latent image is not particularly limited as long as it includes at least ultraviolet rays having a wavelength range of 100 nm to 400 nm. Therefore, in the visualization step, for example, it is possible to visualize the latent image using ultraviolet rays in the wavelength range in the presence of light in the visible range in the room. Note that most of the fluorescent agents used in the present embodiment have a maximum absorption wavelength in the range of 280 nm to 380 nm. For this reason, it is more preferable to include ultraviolet rays within a range of 280 nm to 380 nm in the light used for developing the latent image. Thereby, the ultraviolet absorption by the fluorescent agent is maximized, and the light intensity of the fluorescence emitted by the fluorescent agent can be further increased.

In addition, it is not necessary to block light other than ultraviolet rays in the range of 100 nm to 400 nm using, for example, a filter with respect to the irradiation light. In general, a light emitting device that emits light including an ultraviolet region emits light in the visible light region in addition to the ultraviolet region. Therefore, if a filter or the like is used to block light other than the ultraviolet light in the wavelength range, the ultraviolet light is blocked by the filter as a result. As a result, the cumulative amount of ultraviolet light irradiated on the latent image ink layer. May also decrease. Thereby, the light intensity of the fluorescence emitted from the latent image ink layer may decrease.

Moreover, the wavelength range of the ultraviolet rays contained in the irradiation light can be appropriately set according to the type of the fluorescent agent. Further, the integrated light amount (mJ / cm ² ) of the irradiation light can be appropriately set according to the type of the fluorescent agent, the content in the latent image ink layer, the degree of photodegradability, and the like.

Note that the latent image visualization step may include an observation step of observing the visualized printed image. The observation method is not particularly limited, and imaging means such as a camera may be used in addition to visual observation. The imaging means is not particularly limited, and can be appropriately selected according to the type of fluorescent agent or recording medium.

(Printed matter)
In the printed matter of the first embodiment, at least a latent image ink layer including a latent image is provided on a recording medium. The latent image ink layer printed with the latent image water-based ink of the present embodiment is made of a dry film of the latent image water-based ink and has light transmittance in the visible light region. The dry film is composed of at least a fluorescent agent contained in the latent image aqueous ink composition. The fluorescent agent is uniformly present in the latent image ink layer (dried film of the latent image aqueous ink).

In this specification, the latent image ink layer includes a dry film of a latent image aqueous ink and forms at least a part of a printed image. In addition to the latent image, the printed image includes an image that can be visually recognized under the visible light region. In addition, the type of the print image is not particularly limited, and examples thereof include a pattern, characters, patterns, and combinations thereof. When the recording medium is a solid preparation, the print image is the product information represented by the characters. expressed.

As described above, the latent image ink layer has light transmittance in the visible light region. As used herein, “light transmissive” means a property of transmitting at least part of incident visible light. More specifically, the transmittance of visible light having a wavelength range of 400 nm to 800 nm is 50% or more with respect to the latent image ink layer having a thickness of 2 μm, preferably 50% or more, preferably The case is 70% or more, more preferably 90% or more.

The thickness of the latent image ink layer (after dry coating) is not particularly limited, and is appropriately determined in consideration of the composition and printing speed of the latent image aqueous ink, the fixability of the droplets of the latent image aqueous ink, the drying speed, and the like. Can be set.

The recording medium is not particularly limited, and a conventionally known recording medium can be used. Specific examples include printing paper such as art paper, coated paper, and matte paper. Further, it can be applied to a solid preparation as a recording medium. In the present specification, the term “solid preparation” includes food preparations and pharmaceutical preparations. Examples of solid preparation forms include OD tablets (orally disintegrating tablets), plain tablets, and FC (film coat) tablets. And tablets or capsules such as sugar-coated tablets. The solid preparation may be used for pharmaceuticals or food. Examples of tablets for food use include health foods such as tablet confectionery and supplements. Among solid preparations, the tablet is solid at room temperature, and for example, a tablet prepared by compressing and / or molding a tablet material containing an active ingredient into a certain shape is preferable. The shape of the tablet is not particularly limited, and any shape can be adopted. When applied to a solid preparation as a recording medium, it is possible to prevent deterioration of the printed image of various information printed to improve identification for the user such as product information. It is possible to provide a solid preparation that maintains visibility and prevents dispensing errors and accidental ingestion.

[Embodiment 2]
(Printed product of solid preparation)
The printed matter of the solid preparation according to the second embodiment will be described below.
The printed matter of the solid preparation of the second embodiment has a latent image and a visible image on at least a part of the surface. The meaning of “solid preparation” is as described above.

Further, in this specification, the “latent image” means an image that is difficult to distinguish under an environment irradiated with visible light (wavelength range of greater than 400 nm and less than 760 nm) and is visualized under a specific condition. To do. Further, in this specification, the “visible image” means an image that can be identified in an environment irradiated with visible light (wavelength range: 400 nm to 760 nm). Here, the image printed as a latent image or a visible image can be printed by, for example, an inkjet method using an aqueous inkjet ink.

The latent image is composed of a latent image ink layer. The latent image ink layer is preferably composed of a dry film of an aqueous ink for latent images applicable to inkjet printing (details are as described in Embodiment 1). The dry film can be formed by directly printing on the surface of the solid preparation using the latent ink for latent images, for example, by an inkjet method or the like.

The latent image ink layer has optical transparency in the visible light region (greater than 400 nm and less than 760 nm). This makes it difficult to visually recognize the latent image ink layer under visible light irradiation. As used herein, “light transmissive” means a property of transmitting at least part of incident visible light. More specifically, the transmittance of visible light having a wavelength range of 400 nm to 760 nm is 50% or more with respect to the latent image ink layer having a thickness of 2 μm, preferably 50% or more, preferably The case is 70% or more, more preferably 90% or more. In addition, the term “light transmissivity” means that the latent image ink layer is colored as well as colored.

In addition, the latent image ink layer contains a fluorescent agent, whereby the latent image ink layer emits fluorescence in the visible light region when irradiated with ultraviolet rays having a wavelength range of 100 nm to 400 nm.

The thickness of the latent image ink layer (after dry coating) is not particularly limited, and is appropriately determined in consideration of the composition and printing speed of the latent image aqueous ink, the fixability of the droplets of the latent image aqueous ink, the drying speed, and the like. Can be set.

The visible image is composed of a visible ink layer. The visible ink layer is an ink layer that is visible under visible light irradiation. The visible ink layer is preferably composed of a dry film of a water-based ink for visible images (details will be described later) that can be applied to printing by an inkjet method. The dry film can be formed by printing directly on the surface of the solid preparation using the above-described aqueous ink for visible images, for example, by an ink jet method.

The latent image ink layer and the visible ink layer can be provided in different areas on the surface of the solid preparation. For example, when the solid preparation is a disc-shaped or lens-shaped tablet, a latent image ink layer can be provided on one side and a visible ink layer can be provided on the other side. By making the print areas of the latent image ink layer and the visible ink layer different from each other, it is possible to prevent the visible image and the latent image visualized by emitting fluorescence in the visible light region from being overlapped. , Visibility can be suppressed.

Further, the latent image ink layer and the visible ink layer may be laminated on the surface of the solid preparation at least partially overlapping. Thereby, even when the area of the printable area is small, more information can be recorded on the surface of the solid preparation. In the case where the latent image ink layer and the visible ink layer are laminated in a state where at least a part thereof overlaps, the latent image ink layer is preferably laminated on the visible ink layer. This makes it possible to irradiate the entire area of the latent image ink layer with ultraviolet rays when the ultraviolet rays are irradiated. As a result, the latent image can be visualized in a good state. In addition, since the latent image ink layer has light transmittance in the visible light region, it is possible to suppress a reduction in the visibility of the visible image under visible light irradiation.

(Latent image water-based ink composition and latent image water-based ink)
As the latent image aqueous ink composition used for forming the latent image ink layer according to the second embodiment, the latent image aqueous ink composition used in the first embodiment can be used. Therefore, the detailed description is abbreviate | omitted.

(Water-based ink composition for visible image and water-based ink for visible image)
The visible ink aqueous ink composition used for forming the visible ink layer is not particularly limited, and a conventionally known aqueous ink composition containing at least one dye or pigment and having a main solvent as water can be used. . Further, the water-based ink composition for visible images can be made edible by using a material that complies with the standards of pharmaceutical additives, Japanese pharmacopoeia, or food additives official regulations specified by the Pharmaceutical Affairs Law. In addition, it can be suitably used for recording an image or the like by an inkjet method.

The water-based ink composition for visible image is preferably visible under irradiation with visible light. Thereby, when the visible ink layer is formed using the visible image water-based ink containing the visible image water-based ink composition, identification by visual observation or the like is enabled.

The visible image water-based ink contains at least the visible image water-based ink composition. In particular, when a water-based ink composition for visible images that conforms to the standards of pharmaceutical additives, Japanese pharmacopoeia, or food additives official regulations stipulated by the Pharmaceutical Affairs Law, water-based inks for visible images are edible. Therefore, it is possible to print directly on the surface of a solid agent comprising tablets or capsules such as pharmaceuticals or supplements. In addition, non-contact printing by an ink jet method is possible even for tablets with poor surface smoothness such as uncoated tablets and OD tablets.

(Printing method of solid preparation)
The method for printing a solid preparation according to Embodiment 2 includes at least a visible image printing process for printing a visible image on the surface of the solid preparation, and a latent image printing process for printing a latent image on the surface of the solid preparation. .

The visible image printing step is a step of forming a visible image on the surface of the solid preparation by printing a visible ink layer using the visible image water-based ink. A method for forming the visible ink layer is not particularly limited, but printing by an inkjet method is preferable. More specifically, the printing of the visible ink layer by the ink jet method is performed by ejecting the visible image water-based ink as droplets from a fine nozzle and attaching the droplets onto the solid preparation. There are no particular limitations on the method for ejecting the water-based ink for visible images. For example, a known method such as a continuous ejection type (charge control type, spray type, etc.), on-demand type (piezo type, thermal type, electrostatic suction type, etc.) Can be adopted. Printing conditions such as ink droplet ejection amount and printing speed are not particularly limited, and can be set as necessary.

The visible image printing step may include a drying step of drying the droplets of the visible image water-based ink attached to the surface of the solid preparation. It does not specifically limit as a drying method, In addition to hot air drying, natural drying etc. can be performed. Also, drying conditions such as drying time and drying temperature are not particularly limited, and can be appropriately set according to the discharge amount of the droplets, the type of the aqueous ink composition for visible images, and the like.

The latent image printing step is a step of forming a latent image by printing a latent image ink layer on the surface of the solid preparation using the latent ink for latent images. The method for forming the latent image ink layer is not particularly limited, but as in the case of the visible image printing step, printing by an ink jet method is preferable. The printing of the latent image ink layer by the inkjet method is the same as that in the visible image printing step except that the latent image water-based ink is used. The latent image printing step may include a drying step of drying the latent image aqueous ink droplets attached to the surface of the solid preparation. The drying method and drying conditions are the same as those in the visible image printing step.

Here, when the printing area of the visible image and the printing area of the latent image are made different on the surface of the solid preparation, the order of the visible image printing process and the latent image printing process is not particularly limited. For example, when the latent image printing process is performed before the visible image printing process, the latent image may be printed in an area different from the scheduled printing area of the visible image. In addition, in the case where the visible image printing area and the latent image printing area are at least partially overlapped on the surface of the solid preparation, first, after the visible image is printed in the visible image printing process, the latent image is printed in the latent image printing process. It is preferable to print. As a result, in a region where the visible image and the latent image overlap, the latent image ink layer can be laminated on the visible ink layer, and ultraviolet rays are emitted from the latent image when the latent image ink layer is visualized. The entire area of the ink layer can be irradiated.

It should be noted that the solid pharmaceutical printing method according to the present embodiment may include the latent image visualization step. The visualization step is a step that enables the latent image to be visualized by irradiating the latent image ink layer printed in the latent image printing step with light containing ultraviolet rays in a wavelength region of at least 100 nm to 400 nm. When irradiated with ultraviolet rays, the fluorescent agent uniformly contained in the latent image ink layer absorbs the ultraviolet rays and emits (fluoresces) light in the visible light region (380 nm to 760 nm). Thereby, the entire latent image ink layer in which the fluorescent agent is present emits fluorescence and is visualized.

Here, when the latent image ink layer before ultraviolet irradiation is colorless and transparent in the visible light region, the latent image ink layer can be visualized by fluorescence. In addition, fluorescent dyes (red No. 3, red No. 104, red No. 105 or red No. 106) and basic dyes (chlorophyll or rhodamine) are used as fluorescent agents, and the latent image ink layer before UV irradiation is colored in the visible light region. When it is transparent, the visibility is further improved by the fluorescence of the latent image ink layer.

Irradiation light used for visualization of the latent image is not particularly limited as long as it includes at least ultraviolet rays having a wavelength range of 100 nm to 400 nm. Therefore, in the visualization step, for example, it is possible to visualize the latent image using ultraviolet rays in the wavelength range in the presence of light in the visible range in the room. Note that most of the fluorescent agents used in the present embodiment have a maximum absorption wavelength in the range of 280 nm to 380 nm. For this reason, it is more preferable to include ultraviolet rays within a range of 280 nm to 380 nm in the light used for developing the latent image. Thereby, the ultraviolet absorption by the fluorescent agent is maximized, and the light intensity of the fluorescence emitted by the fluorescent agent can be further increased.

In addition, it is not necessary to block light other than ultraviolet rays in the range of 100 nm to 400 nm using, for example, a filter with respect to the irradiation light. In general, a light emitting device that emits light including an ultraviolet region emits light in the visible light region in addition to the ultraviolet region. Therefore, if a filter or the like is used to block light other than the ultraviolet light in the wavelength range, the ultraviolet light is blocked by the filter as a result. As a result, the cumulative amount of ultraviolet light irradiated on the latent image ink layer. May also decrease. Thereby, the light intensity of the fluorescence emitted from the latent image ink layer may decrease.

Moreover, the wavelength range of the ultraviolet rays contained in the irradiation light can be appropriately set according to the type of the fluorescent agent. Further, the integrated light amount (mJ / cm ² ) of the irradiation light can be appropriately set according to the type of the fluorescent agent, the content in the latent image ink layer, the degree of photodegradability, and the like.

Note that the latent image visualization step may include an observation step of observing the visualized latent image. The observation method is not particularly limited, and imaging means such as a camera may be used in addition to visual observation. The imaging means is not particularly limited, and can be appropriately selected according to the type of fluorescent agent or recording medium.

Hereinafter, preferred embodiments of the present invention will be described in detail by way of example. However, materials, contents, and the like described in the following examples are not intended to limit the scope of the present invention only to those unless otherwise specified. In addition, each material of the water-based ink composition for visible images and the water-based ink composition for latent images conforms to the standards of pharmaceutical additives, Japanese pharmacopoeia, or official food additives defined by the Pharmaceutical Affairs Law.

Example 1-1
As shown in Table 1 below, 0.01% by weight of red No. 3 as a fluorescent agent, 2% by weight of decaglyceryl caprylate (trade name: SY Glister MCA750, manufactured by Sakamoto Yakuhin Kogyo Co., Ltd.) as a surface tension adjuster, As a wetting agent, 30% by mass of propylene glycol and 67.9% by mass of pure water were mixed to prepare a latent image aqueous ink composition according to this example. The obtained aqueous ink composition for latent images was stored in a container that shields from ultraviolet rays (wavelength range: 100 nm to 400 nm) and visible light (400 nm to 760 nm).

Subsequently, the latent image ink layer containing the latent image on the surface of the uncoated tablet is printed on one surface of the uncoated tablet by an inkjet recording method using the latent image aqueous ink composed of the latent image aqueous ink composition. (Printing process, see Table 2 below). The latent image ink layer was light transmissive in the visible light region.

Printing was performed by a single pass (one pass) method using an inkjet printer (KC 600 dpi head, medium speed printing jig). Printing was performed in an environment with an air temperature of 25 ° C. and a relative humidity of 40%. Thereafter, hot air was directly applied with a dryer to sufficiently dry the printed surface. Thus, a sample according to this example was produced.

Subsequently, the latent image ink layer printed on the surface of the uncoated tablet was irradiated with light containing ultraviolet rays having a wavelength range of 280 nm to 350 nm to cause the fluorescent agent contained in the latent image ink layer to fluoresce (visualization). Process). The results are shown in Table 2 below. The visualization process was performed in a dark place.

Example 1-2
In this example, a latent image aqueous ink composition was prepared in the same manner as in Example 1-1 except that Red 104 was used as the fluorescent agent, and the latent image aqueous ink composition was used. Printing on uncoated tablets was performed using the latent image aqueous ink. The results are shown in Table 2 below.

(Example 1-3)
In this example, a latent image aqueous ink composition was prepared in the same manner as in Example 1-1 except that Red No. 105 was used as the fluorescent agent, and the latent image aqueous ink composition was used. Printing on uncoated tablets was performed using the latent image aqueous ink. The results are shown in Table 2 below.

(Example 1-4)
In this example, a latent image aqueous ink composition was prepared in the same manner as in Example 1-1 except that Red 106 was used as the fluorescent agent, and the latent image aqueous ink composition was used. Printing on uncoated tablets was performed using the latent image aqueous ink. The results are shown in Table 2 below.

(Example 1-5)
In this example, aqueous latent ink for latent images was used in the same manner as in Example 1-1 except that 0.1% by mass of tryptophan was used as the fluorescent agent and the pure water content was changed to 67.9% by mass. The composition was prepared, and printing on uncoated tablets was performed using the latent image aqueous ink composed of the latent image aqueous ink composition. The results are shown in Table 2 below.

(Example 1-6)
In this example, a latent image aqueous ink was used in the same manner as in Example 1-1 except that 0.1% by mass of quinine was used as the fluorescent agent and the pure water content was changed to 67.9% by mass. The composition was prepared, and printing on uncoated tablets was performed using the latent image aqueous ink composed of the latent image aqueous ink composition. The results are shown in Table 2 below.

(Result 1)
As shown in Table 2, in each of Examples 1-1 to 1-6, the printed image immediately after the printing process cannot be visually confirmed or is difficult to visually confirm, and all of them show a good latent image. I was able to print. In addition, after the latent image was visualized by irradiating the printed surface with light containing ultraviolet rays having a wavelength range of 280 nm to 350 nm, the printed image could be visualized well.

Example 2-1
<Preparation of aqueous ink composition for visible image>
In the aqueous ink composition of this example, 4% by weight of edible dye (3% by weight of red No. 102, 1% by weight of No. 4 of yellow, 1% by weight of green No. 3) as a dye (manufactured by Daiwa Kasei Co., Ltd.) 2% by weight decaglyceryl caprylate (trade name: SY Glyster MCA-750, manufactured by Sakamoto Yakuhin Kogyo Co., Ltd.) as a surface tension adjusting agent, 30% by weight propylene glycol and 64% by weight pure water as a wetting agent Were mixed to prepare a black water-based ink composition for visible images.

<Preparation of aqueous ink composition for latent image>
As shown in Table 3 below, 0.1% by mass of riboflavin sodium phosphate as a fluorescent agent, and 2% by mass of decaglyceryl caprylate as a surface tension adjuster (trade name: SY Glister MCA-750, Sakamoto Pharmaceutical Co., Ltd.) And 30 wt% propylene glycol as a wetting agent and 67.9 wt% pure water were mixed to prepare a yellow to orange yellow aqueous ink composition for latent images. The obtained aqueous ink composition for latent images was stored in a container that shields from ultraviolet rays (wavelength range: 100 nm to 400 nm) and visible light (400 nm to 760 nm).

<Printing visible images>
Next, printing is performed on one surface of a sugar-coated tablet (sugar-coated layer is sucrose) by an inkjet method using the visible-image aqueous ink composed of the visible-image aqueous ink composition, and the sugar-coated tablet surface is coated with a visible ink layer. A visible image was formed (visible image printing step, see Table 4 below). The visible ink layer was visible under irradiation with visible light.

Printing was performed by a single pass (one pass) method using an inkjet printer (KC 600 dpi head, medium speed printing jig). Printing was performed in an environment with an air temperature of 25 ° C. and a relative humidity of 40%. Thereafter, hot air was directly applied with a dryer to sufficiently dry the printed surface.

<Latent image printing>
Subsequently, printing is performed on the surface of the sugar-coated tablet on which the visible image is printed by using the latent-image aqueous ink composed of the latent-image aqueous ink composition, and the latent image containing the latent image on the sugar-coated tablet surface is printed. An image ink layer was formed (latent image printing step, see Table 4 below). The latent image print area was different from the visible image print area. Further, the latent image ink layer was light transmissive in the visible light region.

Printing was performed by a single pass method using the inkjet printer as in the case of the visible image printing process. Printing was performed in an environment with an air temperature of 25 ° C. and a relative humidity of 40%. Thereafter, hot air was directly applied with a dryer to sufficiently dry the printed surface. Thereby, a printed matter of the solid preparation according to this example was produced.

<Visualization of latent image>
Subsequently, the visible ink layer and the latent image ink layer printed on the surface of the sugar-coated tablet were irradiated with ultraviolet light having a wavelength of 360 nm to cause the fluorescent agent contained in the latent image ink layer to fluoresce (visualization step). The results are shown in Table 4 below. The visualization process was performed in a dark place.

(Example 2-2)
In this example, the water-based ink composition for latent images having the composition shown in Table 3 below was used. The latent image was printed such that the latent image print area overlapped with the visible image print area. Furthermore, FC tablets were used instead of sugar-coated tablets as solid preparations. A printed material of the solid preparation according to this example was prepared in the same manner as in Example 2-1, except for these. Further, the latent image printed on the surface of the sugar-coated tablet was visualized by the same method as in Example 2-1. The results are shown in Table 4 below.

(Result 2)
As shown in Table 4, in each of Examples 2-1 and 2-2, a good visible image could be visually recognized on the surface of the sugar-coated tablet under visible light irradiation. On the other hand, in any solid preparation, the latent image could not be identified under visible light irradiation. Furthermore, when ultraviolet rays having a wavelength of 360 nm were irradiated on the printing surface, fluorescence in the visible light region was generated from the latent image ink layer, and the latent image could be visualized (visualized). As a result, the latent image could be viewed well under the ultraviolet irradiation.

Claims (17)

1. A water-based ink composition for a latent image, having light transmittance in a visible light region, for printing a latent image,
   Including at least a fluorescent agent that emits fluorescence in the visible light region when irradiated with ultraviolet rays having a wavelength range of 100 nm to 400 nm,
   The fluorescent agent is riboflavin, riboflavin butyrate ester, sodium riboflavin phosphate ester, cinnamic acid derivative, L-tryptophan, tyrosine, phenylalanine, quinine, quinine hydrochloride dihydrate, quinine sulfate, red No. 3, red No. 104, Red 105, Red 106, fumarate, at least one selected from the group consisting of chlorophyll and rhodamine,
   The aqueous latent ink composition for latent images, wherein the content of the fluorescent agent is in the range of 0.001% by mass to 10% by mass with respect to the total mass of the aqueous ink composition for latent images.
2. The latent ink composition for latent image is used for printing a latent image in an ink jet system for a solid preparation,
   The aqueous ink composition for latent images according to claim 1, wherein the fluorescent agent is edible.
3. A printed matter in which a latent image is provided on at least a part of the surface of a recording medium,
   The latent image is composed of a latent image ink layer that has optical transparency to visible light and emits fluorescence in the visible light region when irradiated with ultraviolet rays having a wavelength range of 100 nm to 400 nm.
   The latent image ink layer comprises riboflavin, riboflavin butyrate, sodium riboflavin phosphate, cinnamic acid derivative, L-tryptophan, tyrosine, phenylalanine, quinine, quinine hydrochloride dihydrate, quinine sulfate, red No. 3, red 104 No., Red No. 105, Red No. 106, printed matter containing at least one fluorescent agent selected from the group consisting of fumarate, chlorophyll and rhodamine.
4. The latent image ink layer is composed of a dry film of a latent image aqueous ink,
   The latent image water-based ink contains a latent image water-based ink composition containing the fluorescent agent,
   The printed matter according to claim 3, wherein the content of the fluorescent agent is in the range of 0.001% by mass to 10% by mass with respect to the total mass of the aqueous ink composition for latent images.
5. The printed matter according to claim 3 or 4, wherein the recording medium is a solid preparation.
6. The printed matter according to any one of claims 3 to 5, wherein the fluorescent agent is edible.
7. A printed product of a solid preparation in which a latent image and a visible image are provided on at least a part of the surface,
   The latent image is composed of a latent image ink layer that has optical transparency to visible light and emits fluorescence in the visible light region when irradiated with ultraviolet rays having a wavelength range of 100 nm to 400 nm.
   The visible image is a printed product of a solid preparation composed of a visible ink layer that is visible under visible light irradiation.
8. The latent image ink layer comprises riboflavin, riboflavin butyrate, sodium riboflavin phosphate, cinnamic acid derivative, L-tryptophan, tyrosine, phenylalanine, quinine, quinine hydrochloride dihydrate, quinine sulfate, red No. 3, red 104 The printed matter of the solid formulation of Claim 7 containing at least 1 sort (s) of fluorescent agent chosen from the group which consists of No., red 105, red 106, fumarate, chlorophyll, and rhodamine.
9. The latent image ink layer is composed of a dry film of a latent image aqueous ink,
   The latent image water-based ink contains a latent image water-based ink composition containing the fluorescent agent,
   The printed material of the solid preparation according to claim 8, wherein the content of the fluorescent agent is in the range of 0.001% by mass to 10% by mass with respect to the total mass of the aqueous coating composition.
10. 10. The visible ink layer and the latent image ink layer according to any one of claims 7 to 9, wherein the visible ink layer and the latent image ink layer are respectively provided in different regions on the surface, or are sequentially stacked on the surface so as to at least partially overlap each other. Printed product of the described solid preparation.
11. The printed matter of the solid preparation according to any one of claims 7 to 10, wherein the fluorescent agent has edible properties.
12. A method for printing a solid preparation, wherein a latent image and a visible image are printed on at least a part of the surface of the solid preparation,
    On the surface of the solid preparation, a visible ink layer that is visible under irradiation with visible light is printed to form the visible image, and a visible image printing step,
    An area that is different from the visible image print area, an area that is different from the visible image print area, or an area that at least partially overlaps the visible image print area; And a latent image printing step of forming a latent image by printing a latent image ink layer that emits fluorescence in the visible light region when irradiated with ultraviolet rays having a wavelength range of 100 nm to 400 nm.
13. The latent image printing step is a step of printing the latent image ink layer by an inkjet method using a latent image aqueous ink containing a latent image aqueous ink composition,
    The latent ink composition for latent images contains a fluorescent agent that emits fluorescence in the visible light region when irradiated with ultraviolet rays having a wavelength range of 100 nm to 400 nm, and has light transmittance in the visible light region. Item 13. A method for printing a solid preparation according to Item 12.
14. Examples of the fluorescent agent include riboflavin, riboflavin butyrate ester, sodium riboflavin phosphate ester, cinnamic acid derivative, L-tryptophan, tyrosine, phenylalanine, quinine, quinine hydrochloride dihydrate, quinine sulfate, red No. 3, red No. 104, The method for printing a solid preparation according to claim 13, wherein at least one selected from the group consisting of Red No. 105, Red No. 106, fumarate, chlorophyll and rhodamine is used.
15. The method for printing a solid preparation according to claim 13 or 14, wherein the content of the fluorescent agent is 0.001% by mass to 10% by mass with respect to the total mass of the aqueous ink composition for latent images.
16. A method for using a latent image water-based ink for printing a latent image on a recording medium using a latent image water-based ink containing a latent image-based water-based ink composition, comprising:
    On the surface of the recording medium, a latent image ink layer having optical transparency to visible light and emitting fluorescence in the visible light region by irradiation with ultraviolet rays having a wavelength range of 100 nm to 400 nm is printed. A latent image printing process for forming a latent image;
    By irradiating the latent image ink layer with light containing ultraviolet rays having a wavelength range of at least 100 nm to 400 nm, the latent image ink layer generates fluorescence in the visible light region and visualizes the latent image. Including
    As the latent ink composition for latent images,
    Including at least a fluorescent agent that emits fluorescence in the visible light region when irradiated with ultraviolet rays having a wavelength range of 100 nm to 400 nm,
    The fluorescent agent is riboflavin, riboflavin butyrate ester, sodium riboflavin phosphate ester, cinnamic acid derivative, L-tryptophan, tyrosine, phenylalanine, quinine, quinine hydrochloride dihydrate, quinine sulfate, red No. 3, red No. 104, Red 105, Red 106, fumarate, at least one selected from the group consisting of chlorophyll and rhodamine,
    A method of using an aqueous latent image ink, wherein the fluorescent agent is used in an amount of 0.001% by mass to 10% by mass with respect to the total mass of the aqueous latent ink composition.
17. The method for using a latent image water-based ink according to claim 16, wherein a solid preparation is used as the recording medium.