KR100421560B1 - Fluorescent mark formed by fluorescent marking composition - Google Patents

Abstract

PURPOSE: Provided is a fluorescent mark having excellent photoresistance, heat resistance and water resistance with no generation of blotting, and formed by a fluorescent ink composition through a printing device. CONSTITUTION: The fluorescent mark is formed by a fluorescent ink composition comprising organic resin microparticles having a glass transition temperature of 30 deg.C or more and a particle diameter of 30nm or more, and a fluorescent dye which fluoresces in a visible light wavelength region. The fluorescent dye is used in an amount of 0.001-10 wt% based on the weight of the organic resin microparticles. The organic resin is selected from the group consisting of polymethacrylates, polyacrylates, polyvinyl chloride resins, benzoguanamine resins, alkyd resins, urea resins, vinyl acetate copolymers and aromatic sulfonamide resins.

Description

Fluorescent mark formed from a fluorescent ink composition {FLUORESCENT MARK FORMED BY FLUORESCENT MARKING COMPOSITION}

The present invention relates to a fluorescent ink composition and a fluorescent mark formed from the fluorescent ink composition, and more particularly, a fluorescent ink composition having excellent dispersion stability, light resistance, heat resistance, and water resistance without smearing, and formed from the fluorescent ink composition. It relates to a high concentration of fluorescent mark with no bleeding and excellent light resistance, heat resistance and water resistance.

In recent years, information such as a manufacturer, a brand name, etc. of an article is displayed by a barcode, and the stripe pattern is read by an optical detection method, and the use of the merchandise sales and distribution analysis of the article is performed. This type of bar code is usually printed using an ink jet printer or the like, and is suitable for classifying and identifying a product in a store or the like that handles a variety of products. For this reason, in recent years, not only many products using such a barcode system are seen but also those systems have been applied to file management, and the like, for example, used for mail items to which a system for distributing goods by classification by code management is applied. It is becoming.

However, as a method of printing a bar code conventionally, a method of printing a black bar code on a white paper is adopted, and this method uses a difference in reflectance between white paper and black letters. This method has a drawback that it becomes difficult to read, and in this method, since reflected light in the visible region is inevitably used, the appearance of the article may be damaged.

For this reason, as an improved version of such a black and white barcode, an infrared fluorescent barcode that excites by ultraviolet light and emits visible light, or an infrared fluorescent barcode that excites by infrared light and emits infrared light (Japanese Patent Abstract Pyeong 6-500590) ) And the like have been proposed.

By the way, since the phosphor which is excited by ultraviolet light and emits visible light is essentially visible in the visible region, not only does it impair the appearance of the article, but also becomes difficult to read due to dirt on a mark like a black and white barcode. .

In addition, in the case of using an infrared phosphor which is excited by infrared light and emits infrared light, since it does not have light emission in visible light, the presence of a barcode does not damage the appearance of the article and is not affected by marks on the dirt. Although it is possible to detect a mark, these infrared phosphors are made of an infrared fluorescent dye which absorbs and emits light at the wavelength of the infrared region, so that the marked object is likely to absorb ink such as Japanese paper. In this case, when the dye is made into ink and printed by an ink jet printer, bleeding of ink called feathering occurs, resulting in a decrease in read rate and incorrect operation. In addition, although the recording of barcodes tends to be denser, in this case, the intervals between the barcodes become narrower, so this phenomenon becomes a fatal defect and there is a problem in practical use.

In addition, since these conventional inks have a property of dyeing a to-be-marked object, which is inherent to dyes, it becomes difficult to read when the to-be-marked object absorbs infrared light, for example, black. The organic dye used in the present invention has a problem in that it is impossible to decipher the formed mark due to poor light resistance and water resistance.

There are also examples of using inorganic compounds containing neodymium, yttrium, etc. as infrared phosphors (US Patent Publication No. 4, 202, 491, Japanese Patent Publication No. 54-22326, Japanese Patent Publication No. 53-9607) Since the inorganic phosphors have a low rising speed for emitting infrared light, there is a problem in that marks cannot be discriminated from overlapping outputs with adjacent marks when a mark such as a barcode is read at high speed.

The object of the present invention is to obtain a fluorescent ink composition excellent in dispersion stability, light resistance, heat resistance and water resistance without bleeding, and results from various studies in view of such a phenomenon, using a printer such as an ink jet printer In the case of forming a fluorescent mark, there is provided a high concentration of fluorescent mark with no bleeding and excellent light resistance, heat resistance and water resistance.

Further, another object of the present invention is to provide an infrared fluorescent mark that can be read well even when an infrared fluorescent mark is provided on a mark having infrared absorption, and is suitable for densification of a barcode without being limited to the mark.

Further, another object of the present invention is to provide an ink composition for ink jet printers, which has no sedimentation, good storage stability, and no practical problem in terms of practically excellent redispersibility even when dry and solidified due to no aggregation of ink.

1 is an analysis of the Reynolds number of the fluorescent ink composition of the present invention,

2 is an analysis diagram of the weber number of the fluorescent ink composition of the present invention;

3 is a schematic explanatory diagram showing an example of a reader for detecting infrared fluorescence;

4 is a view showing an emission spectrum of a printing surface of a printed matter obtained in Example 5 and Comparative Example 4;

Fig. 5 is a diagram showing the emission spectra of the printing surface of the printed matter obtained in Example 6 and Comparative Example 5.

The fluorescent ink composition of the present invention contains organic fine particles having a glass transition temperature of 30 DEG C or more and a particle diameter of 30 nm or more, or organic particles having a part or all of hollow particles, exhibiting fluorescence in the visible light region, and having a glass transition temperature of 30 It contains organic fine particles having a particle diameter of 30 nm or more, or a part or all of them, hollow particles, and absorbs infrared light having a wavelength of 700 nm or more and emits light in the infrared region.

In addition, the fluorescent ink composition for an ink jet printer of the present invention has a relationship of viscosity (mPa · s) / nozzle diameter (µm) of 0.01 to 1, Reynolds number of 10.5 to 2100, and Weber number of 38.2 to 3360. , The relationship between viscosity (mPa · s) / surface tension is set to 0.03 to 1.0.

In addition, the fluorescent mark of the present invention includes organic fine particles having a glass transition temperature of 30 DEG C or more and a particle diameter of 30 nm or more, or organic particles having a part or all of hollow particles, exhibiting fluorescence in the visible region, and having a glass transition temperature. It contains organic fine particles having a particle diameter of 30 nm or more and a particle diameter of 30 nm or more, or some or all of the organic fine particles having hollow particles, absorbs infrared light having a wavelength of 700 nm or more, emits light in the infrared region, and irradiates infrared light. The rise time of 10 to 90% of the maximum light emission at that time is within 10 mu sec.

[Examples of the Invention]

The organic fine particles contained in the fluorescent ink composition of the present invention preferably have a glass transition temperature of 30 ° C. or more and a particle diameter of 30 nm or more, and the organic fine particles having a glass transition temperature of 30 ° C. or more are printed by, for example, an ink jet printer. The stability of the printed matter is good and good stability is obtained even when the ink is heated to around 40 ° C. for the purpose of speeding up the drying of the ink as in recent years so that stability against heat is required.

In particular, in a system of a printing apparatus, the temperature of the ink may rise to around 30 ° C. In particular, in the case of storing the ink in the summer, the organic fine particles exhibit adhesiveness due to the properties of the raw material. Causes aggregation of. Moreover, since the adhesiveness of organic fine particles is seen after forming an image, for example, an image may be transferred to a contact such as when an image is formed on paper. However, when the glass transition temperature of the organic fine particles is 30 ° C. or higher, Even if it becomes high temperature, the ink which is excellent in storage stability and heat resistance which does not raise a viscosity and does not transfer after image formation is obtained.

In addition, the glass transition temperature of the organic fine particles is not particularly limited as long as it is 30 ° C. or higher because the above properties are sufficiently expressed when the temperature is 30 ° C. or higher. Is more preferable.

When the organic fine particles of the present invention have a particle diameter of 30 nm or more, dispersion stability equivalent to that of a dye is obtained, and sufficient print concentration is obtained. When the organic fine particles of 30 nm or more are used, a dye can be contained in the organic fine particles. The bleeding of ink can be suppressed favorably. In addition, when it is 30 nm or more, it is easy to control the particle diameter in manufacturing, and when using it for an ink jet printer, since redispersibility of ink is required, it is necessary not to form a film (form: film | membrane). However, in the ink using the organic fine particles of the present invention, the wettability with the solvent is good, and therefore, an ink suitable for this point can be obtained.

In addition, since the concealability improves as the particle size increases, the larger the particle size, the larger the particle size becomes, and thus the image becomes clearer. However, from the viewpoint of versatility, 30 nm or more and 2 μm or less are preferable, and 30 nm or more and 0. 8 micrometers or less are more preferable.

As described above, in the ink composition of the present invention, when the organic fine particles are 30 nm or more and 30 ° C. or more, an image having good thermal stability and redispersibility of ink and no transferability can be obtained.

Moreover, when using these organic microparticles | fine-particles, it is more preferable to use a hollow particle among organic microparticles | fine-particles, and the organic microparticles | fine-particles whose one part is a hollow particle are also used preferably. Since the hollow particles contain a solvent in the particles, the specific gravity does not increase even when the particle diameter is increased, and even when the ink concentration is increased, the ink is not deposited and an ink having excellent redispersibility can be obtained. Moreover, since the refractive index at the time of irradiating light with a hollow particle differs in particle surface and inside after image formation, it is also preferable at the point which can improve concealment more.

If the glass transition temperature is 30 ° C. or higher and the organic particles having a particle diameter of 30 nm or more or some or all of the organic particles are hollow particles together with a fluorescent dye or a white fluorescent brightener, the glass transition temperature is 30. An organic composition containing organic fine particles having a particle diameter of 30 nm or more and a particle diameter of 30 nm or more, or a part or all of hollow particles, which exhibits fluorescence in the visible light region is obtained, and has excellent heat resistance and dispersion stability and no bleeding. A fluorescent marking composition excellent in light resistance and water resistance is obtained.

In the organic fine particles having a glass transition temperature of 30 DEG C or more and a particle diameter of 30 nm or more, or organic particles having a part or all of hollow particles, a fluorescent dye or a white fluorescent brightener is formed by a bulk resin pulverization method, an emulsion polymerization method, When the resin is precipitated or the like, the free colored fluorescent dye is trapped into the organic fine particles or the organic fine particles in which part or all of them are hollow particles so as to be impregnated and firmly bonded to each other. The fluorescent organic pigment which continued as it is is obtained, and a fluorescent ink composition is obtained using such fluorescent organic pigment. Fluorescent ink compositions using such fluorescent organic pigments have properties as pigments, and unlike fluorescent dyes, fluorescing does not occur even when used for forming marks on paper and the like, and is excellent in dispersion stability, light resistance, water resistance, and color development. Since it is a pigment, concealability can be provided and it can prevent it from being influenced by the lower limb (base) at the time of printing.

Here, the bulk resin pulverization method is a method of pulverizing solids obtained after melt mixing and cooling a fluorescent dye or a white fluorescent brightener with organic fine particles or organic particles in which some or all of them are hollow particles, and emulsion polymerization method A method of adsorbing and dyeing the fluorescent dye or white fluorescent brightener into a suspension of the organic fine particles obtained by emulsion polymerization or a part or all of the hollow microparticles, and the resin precipitation method is the organic fine particles and the fluorescent dye or white fluorescent brightener. The reaction solution was added with an aqueous solution of a metal salt to dissolve the solution. The liquid was acidified as necessary, and dissolved organic particles or organic particles in which part or all were hollow particles were adsorbed with a fluorescent dye or a white fluorescent brightener. It precipitates as a thin metal salt, and this is the method of filtration and drying.

Examples of the organic fine particles having a glass transition temperature of 30 ° C. or higher and a particle diameter of 30 nm or more include polymethacrylic acid ester, polyacrylic acid ester, polyvinyl chloride, benzoguanamine resin, alkyd resin, urea resin, vinyl chloride, and vinyl acetate. Copolymer, aromatic sulfonamide resin, etc. are used as a suitable thing, As a specific example, Nippon Paint Co., Ltd. make; Microgels, manufactured by Rohm Haas; Acrylic emulsion and Nippon Synthetic Rubber Co., Ltd .; Organic fine particles, manufactured by Mitsui Petrochemical Co., Ltd .; CHEMIPEARL etc. are mentioned. Moreover, as a hollow particle, polymethacrylic acid ester, polyacrylic acid ester, etc. are used as a suitable thing, As a specific example, Nippon synthetic rubber company; Hollow particles, manufactured by Rohm Haas; Hollow particles; and the like.

In addition, in combination with organic fine particles having a glass transition temperature of 30 ° C. or more and a particle diameter of 30 nm or more, or organic particles in which part or all of them are hollow particles, fluorescent organic pigments may be prepared from these organic particles or in part or all of organic particles of hollow particles. As the fluorescent dye used for obtaining, any structure may be used. For example, an acid dye, a direct dye, a cationic dye, a mordant dye, an acid mordant dye, a disperse dye, a reactive dye, an oxidizing dye, etc. are preferably used. . In addition, a white fluorescent brightener is preferably used alone or in combination with these fluorescent dyes.

Specific examples of the fluorescent dyes include ACID YELLOW3, ACID YELLOW7, ACID RED52, ACID RED77, ACID RED87, ACID RED92, ACID BLUE9, BASIC YELLOW1, BASIC YELLOW40, BASIC RED1, BASIC RED13, which are indicated by the color index number (C · I). VIOLET7, BASIC VIOLET10, BASIC ORANGE22, BASIC BLUE7, BASIC GREEN1, DISPERSE YELLOW121, DISPERSE YELLOW82, DISPERSE ORANGE11, DISPERSE RED58, DISPERSE BLUE7, DIRECT YELLOW85, DIRECT ORANGE8, DIRECT BLUE DIR9 DIRNENT WHITEX WS52, FLUORESCENT162, FLUORESCENT112, SOLVENT YELLOW44, SOLVENT RED49, SOLVENT BLUE5, SOLVENT PINK, SOLVENT GREEN7, PIGMENT BLUE15, PIGMENT GREEN7, PIGMENT RED53, PIGMENT RED57, PIGMENT YELLOW1.

As a specific example of the white fluorescent brightener, Fluorescent Brightening Agent 85, 86, 22, 174, 166, 90, 134, 84, 24, 87, 175, 176, 169, 167, 173, 14, 32, 30, 177, 153 , 168, 37, 104, 45, 55, 52, 54, 56, 171, 170, 135, 162, 163, 164, 112, 121, 172, 91 and the like.

When the fluorescent organic pigment is obtained, the content ratio of the fluorescent dye or the white fluorescent brightener impregnated in the organic fine particles or the organic fine particles in which some or all of them are hollow particles ranges from 0.001 to about the organic fine particles in which the organic fine particles or some or all of them are hollow particles. It is preferable to exist in the range of 10 weight%, and when it is less than this, sufficient color will not be obtained and sufficient color may not be obtained.

In addition, when organic particles or glass particles having a glass transition temperature of 30 ° C. or more and a particle diameter of 30 nm or more, or organic particles in which part or all of them are hollow particles are used together with organic dyes or white fluorescent brighteners that fluoresce in the infrared wavelength region of 700 nm or more, And an ink composition containing organic fine particles having a glass transition temperature of 30 ° C. or more and a particle diameter of 30 nm or more, or organic particles having a part or all of hollow particles, absorbing an infrared wavelength of 700 nm or more and emitting light in an infrared region. A fluorescent ink composition is obtained that is excellent in heat resistance and dispersion stability and does not generate bleeding and is excellent in light resistance and water resistance.

In addition, the organic resin or white fluorescent brightener, which exhibits fluorescence in the infrared wavelength region of 700 nm or more, in organic particles having a glass transition temperature of 30 ° C. or more and a particle diameter of 30 nm or more, or some or all of the hollow particles, are pulverized in bulk resin. Process, emulsion polymerization method, resin precipitation method, etc., the organic dye or white fluorescent brightener which fluoresces in the advantageous colored infrared wavelength region is trapped in organic fine particles or organic particles in which part or all of them are hollow particles and impregnated firmly. An infrared fluorescent organic pigment which is bound and retains the properties of an organic dye or a white fluorescent brightener that exhibits fluorescence in the infrared wavelength region is obtained, and an infrared fluorescent ink composition is obtained using such an infrared fluorescent organic pigment. Such a fluorescent ink composition using an infrared fluorescence organic pigment has a property as a pigment, and unlike fluorescent dyes, it is excellent in dispersion stability, light resistance, water resistance, color development, without bleeding even when used for forming marks on paper, etc. Moreover, since it is a pigment, concealability can be provided and it can prevent it from being influenced by the lower part at the time of printing.

As an organic dye exhibiting fluorescence in the infrared wavelength region of 700 nm or more, any structure can be used. For example, a polymethine dye, an anthraquinone dye, a dithiol metal salt dye, a phthalocyanine dye, or an indophenol A dye, an aluminum dye, a dimonium dye, an azo dye and the like are preferably used, and a polymethine dye is more preferably used in terms of weatherability. Moreover, the same thing as what is used for the said fluorescent ink composition as a white fluorescent brightener is used preferably, You may mix colored dyes.

As a specific example of a polymethine type pigment | dye, KODAK LABORATORIES Chemical Co., Ltd. make; IR-140, IR-820B by Nippon Kayaku Co., Ltd., etc. are mentioned, As a specific example of an anthraquinone type pigment | dye, IR-750 by Nippon Kayaku Co., etc. are mentioned. Moreover, as a specific example of a dithiol metal salt type pigment | dye, the Mitsui Toatsu company make; Tetrabutyl phosphononium (1, 2- benzene thiolite) nitrate (III) etc. are mentioned, As a specific example of a phthalocyanine type pigment | dye, Zn-phthalocyanine etc. are mentioned. Moreover, as a specific example of a white fluorescent brightener, the Nippon Kayaku Co., Ltd. make; Mica white ACR, Kayapor 3BS, etc. are mentioned.

When obtaining an infrared fluorescence organic pigment, the content rate of the organic dye or white fluorescent brightener which fluoresces in the infrared wavelength region of 700 nm or more which is impregnated and bonded to organic microparticles | fine-particles or some or all the hollow particle | grains is organic microparticles or a part or It is preferable that it is in the range of 0.01 to 15 weight% with respect to the organic fine particles which are all hollow particles, and when less than this, sufficient color and fluorescent effect are not obtained. Moreover, even if too many, the color becomes too dark and sufficient color is not obtained, concentration quenching occurs and fluorescence is not obtained.

As such, organic fine particles having a glass transition temperature of 30 ° C. or more and a particle diameter of 30 nm or more, or organic particles having a part or all of hollow particles in combination with a fluorescent dye or a white fluorescent brightener, or a glass transition temperature of 30 ° C. or more An ink composition using a fluorescent organic pigment impregnated with a fluorescent dye or a white fluorescent brightener impregnated with organic fine particles having a particle diameter of 30 nm or more or a part or all of hollow particles, and a glass transition temperature of 30 ° C. or higher, The organic fine particles of 30 nm or more or the organic particles of some or all of the hollow particles may be used in combination with an organic dye or a white fluorescent brightener having absorption in the infrared wavelength region of 700 nm or more, or the glass transition temperature is 30 ° C. or more and the particle diameter Infrared wavelength range of 700 nm or more to organic fine particles of 30 nm or more or organic particles of which some or all are hollow particles An ink composition using an infrared fluorescent organic pigment obtained by impregnating an organic dye or a white fluorescent brightener having an absorption into an organic fine particle or an organic fine particle of which all or part is a hollow particle is an organic fine particle of these organic fine particles or part or all of hollow particles. And fluorescent dyes or white fluorescent brighteners or fluorescent organic pigments, organic fine particles of which organic particles or part or all of them are hollow particles, and organic dyes or white fluorescent brighteners or infrared fluorescent organic pigments having absorption in the infrared wavelength region of 700 nm or more. It is prepared by mixing and dispersing together with the binder resin and the solvent if necessary.

Here, as binder resin, all conventionally used things are used, For example, polyvinyl alcohol, an acrylic resin, polyethylene oxide, starch, the formalin condensate of naphthalene sulfonate, carboxymethyl cellulose, etc. are used.

Moreover, as a solvent used as needed, water, alcohol, a ketone, ester, an ether, an aromatic hydrocarbon solvent, an aliphatic hydrocarbon solvent, etc. are used individually or in mixture.

Fluorescent ink compositions and infrared fluorescent ink compositions prepared in this way are used in various printing methods, such as for ink jet printers, screen printing, offset printing, gravure printing, convex printing, tampon printing, and the like. Dispersing agents, antifoaming agents, surfactants, moisturizing agents, conductivity giving agents and the like are used.

In particular, the fluorescent ink composition and the infrared fluorescent ink composition for ink jet printers have a relationship of viscosity (mPa · s) / nozzle diameter (μm) in the range of 0.01 to 1, Reynolds number in the range of 10.5 to 2100, and webber It is preferable that the number is in the range of 38.2 to 3360 and the relationship of viscosity (mPa · s) / surface tension is in the range of 0.04 to 1.0, and the relationship of viscosity (mPa · s) / nozzle diameter (μm) is 0.03 to 1 If it is in a range, a good mark can be formed, but if it is out of this range, a good mark cannot be formed.

Here, the principle which becomes the center of inkjet printing is considered to be the formation of droplets (liquid droplets) due to the breakup of jets and the electronic control in the flight direction of the droplets. The formation of the droplets is represented by Rayleigh's equation of motion, and the optimum fluid dynamics of the ink are obtained from the solution, but are also derived from the design conditions of the apparatus as various dimensional indices of construction [A. Kinoshita, Lecture at Print and Information Records Training Institute, Lecture Summary (1987)]. Although there are various such dimensionless numbers, there are Reynolds number and Weber number regarding ink.

Therefore, as a result of examining the Reynolds number using the ink composition of the present invention, the Reynolds number is R = ρνlη ^-1 (where, ρ = density (g / cm 3), ν: flow rate (m / s), l: Nozzle diameter (mu m) and η: viscosity (mPa · s).

Here, when the droplets can be formed and the range in which the ink flows is represented by the Reynolds number, it is necessary to be within the range of 10.5 to 2100. In the ink composition of the present invention, when the Reynolds number is out of the above range, satellite droplets (ink droplets of small particle diameter, not main ink droplets) are irregularly formed, and ink splashing occurs, and thus the desired image is produced. It was difficult to form.

In addition, as a result of conducting an examination for selecting various nozzle diameters of ink jet printers, printing barcodes, and reading barcode outputs, it is possible to form a clear image with a diameter of 80 µm, which enables printing of high output. Became clear. Therefore, as a result of conducting the printing experiment by changing the flow velocity and viscosity with the nozzle diameter of 80 µm, the flow velocity could be changed to 10 to 20 m / s, and the viscosity could be changed to 2 to 20 mPa · s. When this is shown, it is shown by the curved surface as shown in FIG. 1, and it turns out that the Reynolds number in this case is 42-840.

Next, as a result of investigating the Weber number, W = ρν2lγ ⁻¹ (where, ρ: density (g / cm 3), ν: flow rate (m / s), l: nozzle diameter (μm), and γ: surface tension (mN M- ¹ ), the web number needs to be in the range of 38.2 to 3360 in consideration of the formation of ink droplets and bubbling of the ink. In the ink composition of the present invention, when the webber number is out of the above range, the ink bubbles are severe, and printing is impossible.

As a more preferable range of Weber numbers in the case of carrying out the bar code factor, the examination was carried out by fixing the nozzle diameter to 80 mu m as in the above-mentioned Reynolds number. As a result, the flow rate was 10-20 m / s and the surface tension was 25-55 mN. M ^-1 could be changed. When this is shown, it is shown by the curved surface like FIG. 2, and it turns out that the webber number in this case changes from 152 to 1360.8.

In addition, it is necessary to take into account the function of viscosity and surface tension, not bubble formation, when the ink jet printer prints by spraying ink, but the viscosity (mPa · s) in the ink composition of the present invention. When the relationship between the? / Surface tension (mN · m ⁻¹ ) is within the range of 0.03 to 1.0, a good factor could be executed. For this reason, when using the ink composition of this invention as ink for inkjet printers, it is preferable to make the relationship of a viscosity (mPa * s) / surface tension in the range of 0.03-1.0.

The fluorescent mark formed from such a fluorescent ink composition and an infrared fluorescent ink composition exhibits fluorescence in the visible light region or absorbs infrared light with a wavelength of 700 nm or more and emits light in the infrared region, and particularly infrared light with a wavelength of 700 nm or more. Infrared fluorescent mark that absorbs light and emits light in the infrared region does not damage the appearance of the article because there is no absorption and light emission in the visible region, and is further affected by the dirt on the mark such as the material and shape of the marked object. It is possible to form an infrared fluorescent mark without any work.

Here, when the mark which fluoresces in the infrared wavelength range of 700 nm or more is affixed on the white to-be-marked object whose reflectance of the infrared light of wavelength 700 nm or more is 50% or more, the reflection output (standard white, a standard color paper made by the laboratory): standard back No.18) of the C _0, and when the output of, as measured by irradiating infrared light to the infrared fluorescent mark to C _1, and preferably not more than 4%, the ratio of C ₀ / C _1, C ₀ / C _If the ratio of ₁ is 4% or less, a read rate that is not erroneously operated can be ensured even if the read operation is performed.

In addition, when attaching an infrared fluorescent mark to a black target material having a reflectance of infrared light having a wavelength of 700 nm or more and 10% or less, the output when the infrared fluorescent mark is irradiated with infrared light and measured is C ₂ . It is preferable that the ratio C ₂ / C ₁ between the output C ₁ and ₂ measured by irradiating infrared light to ₂ and the infrared fluorescent mark is 5% or more, and when C ₂ / C ₁ is 5% or more, the infrared phosphor on the standard white The infrared fluorescent mark can be read without misdetecting the infrared fluorescent mark, and the infrared fluorescent mark can be read without any problem even if it is on a black mark.

On the other hand, when only the output ratio C ₀ / C ₁ on the standard white is 4% or less, even if a mark indicating fluorescence in the infrared wavelength region of 700 nm or more can be detected without a problem, if the lower limb is colored, for example, black In particular, when an infrared phosphor mark is provided on a marked object containing carbon black, sufficient output cannot be obtained, resulting in a misreading operation.

In addition, when the infrared fluorescent mark attached on the mark is executed at high speed, it is necessary to speed up the response speed from the infrared fluorescent mark. However, when the infrared fluorescent mark of the present invention is used, the maximum output is 10 to 90. It is possible to set the% rise time to within 10 mu sec, and sufficient excitation light can be obtained even at a high speed reading of 4 m / s or more.

The infrared fluorescent marks formed in this way can be made less susceptible to dirt on the marks and smears of the ink, and at the same time can be less affected by the underlying material of the mark. In addition, even when an infrared fluorescent mark is provided on a to-be-marked object having infrared absorption, an infrared fluorescent mark that can be read well and which is suitable for densification of a barcode can be obtained.

As a reader which can be used in combination with a fluorescence mark in the infrared wavelength region of the present invention thus obtained, any reader having a function capable of irradiating infrared light and detecting infrared fluorescence can be used without particular problem. The reader shown in FIG. 3 is used.

Hereinafter, the reader shown in FIG. 3 will be described. The reader shown in FIG. 3 is composed of a reader optical system and a reading circuit, and the reader optical system includes a semiconductor laser drive circuit 1, a semiconductor laser 2, and a lens 3 And a total reflection mirror 4, flat iron lenses 5 and 6, a slit 7, a filter 8 and a photodiode 9.

The excitation light 10 irradiated from the semiconductor laser 2 is focused to a diameter of 1 mm by the lens 3, passes through a transmission hole 41 drilled in the center of the mirror 4, and the lens ( 5) is irradiated perpendicularly to the plane of the infrared fluorescence mark carrier 11. At this time, if the excitation light 10 is emitted to the mirror 4 side without focusing, a part of the excitation light 10 is cut off (cut) by the outer peripheral portion of the transmission hole 41, and thus the infrared fluorescent mark side Since the amount of light (excitation energy) of the excitation light 10 reaching to substantially decreases, and as a result, the light emission output is small, it is necessary to regulate the focusing diameter of the excitation light 10 to be equal to or less than the diameter of the transmission hole 41. There is.

The infrared fluorescent mark 12 is conveyed on the infrared fluorescent mark carrier 11 at high speed, the excitation light 10 is irradiated to the infrared fluorescent mark 12, the infrared fluorescent material is excited, and the fluorescence is first flat iron lens. It is received by (5). The received light is reflected by the mirror 4, focused by the second flat lens 6, transmitted through the slit member 7 and the filter 8, and received by the photodiode 9.

The reading circuit is composed of a detection circuit 13 having an amplification circuit and a filter circuit, a binarization processing circuit 14, a decode circuit 15, a serial interface 16, and a personal computer 17 for data processing. .

EXAMPLE

Next, the Example of this invention is described. In addition, of course, this invention is not limited to these Examples.

Example 1

Rhodamine B (Sumitomo Chemical Co., Ltd.): Reddish violet dye, CIBasic Violet 10 based on 100 parts by weight of the hollow particle dispersion of the styrene acrylic acid ester resin (20 wt% of solid content, 0.3 μm of particle diameter, glass transition temperature of 30 ° C.) , CAS No.:81-88-9) A solution in which 0.3 parts by weight was dissolved in 6 parts by weight of ethanol was added, stirred and mixed to obtain a pink fluorescent organic pigment.

To this, 10 parts by weight of John Krill 61 (manufactured by Johnson Polymer; acrylic styrene resin, solid content of 30% by weight) and 20 parts by weight of water were added, mixed and dispersed by a ball mill for 3 hours, and then the ink composition was passed through a 1 μm filter. It prepared. This ink composition had a Reynolds number of 560, a Weber number of 1018, a viscosity / nozzle diameter of 0.0375, and a viscosity / surface tension of 0.09.

Then, the ink composition thus obtained was used to print on paper with an ink jet printer.

Example 2

Rhodamine B (manufactured by Sumitomo Chemical Co., Ltd .: reddish violet dye, CIBasic Violet 10, CAS No. 1) based on 100 parts by weight of an emulsion polymerization solution of a styrene acrylic ester resin (solid content 30% by weight, particle diameter 50nm, glass transition temperature 50 ° C). : 81-88-9) A solution in which 0.3 parts by weight was dissolved in 6 parts by weight of ethanol was added, stirred and mixed to obtain a pink fluorescent organic pigment.

To this, 10 parts by weight of John Krill 61 (manufactured by Johnson Polymer; acrylic styrene resin, solid content of 30% by weight) and 20 parts by weight of water were added, mixed and dispersed by a ball mill for 3 hours, and then the ink composition was passed through a 1 μm filter. It prepared. This ink composition had a Reynolds number of 400, a Weber number of 842, a viscosity / nozzle diameter of 0.05 and a viscosity / surface tension of 0.1.

The ink composition thus obtained was used to print on paper using an ink jet printer.

Example 3

0.2 parts by weight of Astrazone Red 6B (manufactured by Bayer, Red Dye, CI Basic Violet 7) with respect to 100 parts by weight of an emulsion polymerization solution of a styrene acrylic ester resin (solid content 30% by weight, particle diameter 50nm, glass transition temperature 50 ° C) A solution dissolved in 4 parts by weight was added, stirred and mixed to obtain a pink fluorescent organic pigment.

To this, 10 parts by weight of John Cryl 61 (manufactured by Johnson Polymer; acrylic styrene resin, 30% by weight of solid content) and 20 parts by weight of water were added, mixed and dispersed by a ball mill for 3 hours, and then the ink composition was passed through a 1 μm filter. It prepared. This ink composition had a Reynolds number of 315, a Weber number of 473, a viscosity / nozzle diameter of 0.05 and a viscosity / surface tension of 0.1.

The ink composition thus obtained was used to print on paper using an ink jet printer.

Example 4

Sola Pure Yellow 8G (Sumitomo Chemical Co., Ltd .: Yellow Dye) 0.2 part by weight based on 100 parts by weight of an emulsion polymerization solution of styrene acrylic acid ester resin (solid content 30% by weight, particle diameter 50nm, glass transition temperature 50 ° C) A solution dissolved in parts by weight was added, stirred and mixed to obtain a pink fluorescent organic pigment.

To this, 10 parts by weight of John Cryl 61 (manufactured by Johnson Polymer; acrylic styrene resin, 30% by weight of solid content) and 20 parts by weight of water were added, mixed and dispersed by a ball mill for 3 hours, and then the ink composition was passed through a 1 μm filter. It prepared. This ink composition had a Reynolds number of 236, a Weber number of 405, a viscosity / nozzle diameter of 0.067 and a viscosity / surface tension of 0.11.

The ink composition thus obtained was used to print on paper using an ink jet printer.

Example 5

Peak of IR-820 (Nippon Kayaku Co .; Polymethine Dye, Absorption Wavelength) with respect to 100 parts by weight of an emulsion polymerization solution (30 wt% of solid content, 30 nm in particle diameter, glass transition temperature of 40 ° C.) of styrene acrylic acid ester resin: 820 nm, emission wavelength peak: 900 nm) A solution obtained by dissolving 0.15 parts by weight of acetone in 5 parts by weight was added while stirring to obtain an infrared fluorescent organic pigment.

To this, 10 parts by weight of John Cryl 61 (manufactured by Johnson Polymer; acrylic styrene resin, solid content of 30% by weight) and 10 parts by weight of water were added, and dispersed in a ball mill for 3 hours to prepare an ink composition. The Reynolds number of this ink composition was 475, the Weber number was 1008, the viscosity / nozzle diameter was 0.0438, and the viscosity / surface tension was 0.11.

The ink composition thus obtained was printed using a ink jet printer on a single piece of Japanese paper classified into portions having a reflectance of 800 nm infrared light at 70% and portions at 5%.

Example 6

IR-140: Laser Pigment, CAS No. 53655-17-7 (Kodala Borato) with respect to 100 parts by weight of an emulsion polymerization solution of a styrene acrylic ester resin (solid content 30% by weight, particle diameter 40nm, glass transition temperature 40 ° C) Liz Chemical Co., Ltd .: Polymethine-based dyes, absorption wavelength peak: 826 nm, emission wavelength peak: 870 nm) 0.1 parts by weight of a solution dissolved in 5 parts by weight of dimethyl sulfoxide was added with stirring to obtain an infrared fluorescent organic pigment.

To this, 10 parts by weight of John Cryl 61 (manufactured by Johnson Polymer; acrylic styrene resin, 30% by weight of solid content) and 10 parts by weight of water were added, and dispersed in a ball mill for 3 hours to prepare an ink composition. This ink composition had a Reynolds number of 216.3, a Weber number of 463.5, a viscosity / nozzle diameter of 0.0714 and a viscosity / surface tension of 0.14.

The ink composition thus obtained was printed using a ink jet printer on a single piece of Japanese paper classified into a portion having a reflectance of 60% at 800 nm for 60% and a portion having 3%.

Example 7

Peak of IR-820 (Nippon Kayaku Co .; Polymethine Dye, Absorption Wavelength) with respect to 100 parts by weight of an emulsion polymerization solution (30 wt% of solid content, 30 nm in particle diameter, glass transition temperature of 40 ° C.) of styrene acrylic acid ester resin: 820 nm, emission wavelength peak: 900 nm) A solution obtained by dissolving 0.15 parts by weight of acetone in 5 parts by weight was added while stirring to obtain an infrared fluorescent organic pigment.

To this, 10 parts by weight of John Cryl 61 (manufactured by Johnson Polymer; acrylic styrene resin, 30% by weight of solid content) and 10 parts by weight of water were added, and dispersed in a ball mill for 3 hours to prepare an ink composition. This ink composition had a Reynolds number of 288, a Weber number of 721, a viscosity / nozzle diameter of 0.0714 and a viscosity / surface tension of 0.13.

The ink composition thus obtained was printed using a ink jet printer on a single piece of Japanese paper classified into portions having a reflectance of 800 nm infrared light at 70% and portions at 5%.

Comparative Example 1

Rhodamine B (manufactured by Sumitomo Chemical Co., Ltd .: reddish violet dye, CIBasic Violet 10,) with respect to 100 parts by weight of an emulsion polymerization solution of organic fine particles (20 wt% solids, 20 nm particle diameter, glass transition temperature 40 ° C.) of styrene acrylic ester resin CAS No.:81-88-9) A solution in which 0.15 parts by weight was dissolved in 4 parts by acetone was added while stirring to obtain a red fluorescent organic pigment.

20 weight part of water was added to this, and it mixed and dispersed for 3 hours by the ball mill, and prepared the ink composition through the 1 micrometer filter.

The ink composition thus obtained was used to print on paper using an ink jet printer.

Comparative Example 2

0.3 parts by weight of Astrazone red 6B (manufactured by Bayer, red dye, CI Basic Violet 7) with respect to 100 parts by weight of an emulsified polymerization solution of butyl acrylate (30 wt% of solid content, 3 μm of particle diameter, 30 ° C. or less of glass transition temperature). The solution dissolved in the weight part was added while stirring to obtain a yellow fluorescent organic pigment.

20 weight part of water was added to this, and it mixed and dispersed for 3 hours by the ball mill, and the ink composition was prepared through the 5 micrometer filter.

The ink composition thus obtained was used to print on paper using an ink jet printer.

Comparative Example 3

Rhodamine B (manufactured by Sumitomo Chemical Co., Ltd .: reddish violet dye, CIBasic Violet 10, CAS No.:81-88-9) 2 parts by weight, 80 parts by weight of water, 15 parts by weight of glycerin, 15 parts by weight of ethylene glycol are stirred and mixed, 1 An ink composition was prepared through a filter of μm.

The ink composition thus obtained was used to print on paper using an ink jet printer.

Comparative Example 4

IR820B: John Krill 61 (Johnson) which melt | dissolved 0.15 weight part of near-infrared absorption pigments (made by Nippon Kayaku Co., Ltd .; polymethine pigment | dye, absorption wavelength peak: 820 nm, light emission wavelength peak: 900 nm) in 2 parts by weight of acetone. 30 parts by weight of an acrylic styrene resin, 30% by weight of a solid content) and 90 parts by weight of water were added to the mixed solution to prepare an ink composition.

The ink composition thus obtained was printed using a ink jet printer on a single piece of Japanese paper classified into portions having a reflectance of 800 nm infrared light at 70% and portions at 5%.

Comparative Example 5

IR-140: 0.05 parts by weight of DMSO (dimethyl laser, CAS No. 53655-17-7 (manufactured by KODAK LABORATORIES Chemical Co., Ltd .; polymethine dye, absorption wavelength peak: 826 nm, emission wavelength peak: 870 nm)) The solution dissolved in 5 parts by weight of sulfoxide) was added to the solution obtained by mixing 30 parts by weight of John Cryl 61 (manufactured by Johnson Polymer; acrylic styrene resin, solid content of 30% by weight) and 90 parts by weight of water to prepare an ink composition.

The ink composition thus obtained was printed using a ink jet printer on a single piece of Japanese paper classified into a portion having a reflectance of 60% at 800 nm for 60% and a portion having 3%.

Comparative Example 6

Inorganic Phosphor LiNd _0.5 Yb _0.5 P ₄ O ₁₂ (Composite of Inorganic Infrared Phosphor, Synthesis Method USP 5,611,958 [Example 13, Comparative Example 1, Corresponding Japanese Patent: JP-A-7-90265 No., Japanese Patent Application Laid-Open No. Hei 7-90266; 8 parts by weight of LiNd _0.9 Yb _0.1 P ₄ O ₁₂ or LiNd _0.1 Yb _0.9 P ₄ O ₁₂ having a composition similar to that of John Cryl 61 (manufactured by Johnson Polymer; Acrylic) Styrene resin, solid content 30%) 6 parts by weight and 40 parts by weight of water were dispersed by a ball mill to prepare an ink composition.

The ink composition thus obtained was printed using a ink jet printer on one Japanese paper classified into portions having a reflectance of 800 nm infrared light at 70% and portions at 5%.

The ink compositions and printed matters obtained in Examples 1 to 4 and Comparative Examples 1 to 3 were tested for storage stability, light resistance, bleeding properties, redissolution and transfer characteristics by the following method.

In addition, in the present embodiment and the comparative example, as an ink jet printer, an ink jet printer manufactured by Hitachi Seisakusho Co., Ltd .; Printing was performed using GX-PA (nozzle diameter: 80 µm), and the glass transition temperature of the organic fine particles was measured using a differential scanning calorimeter (DSC-7) manufactured by Perkin-Elmer. It is measured by heating the sample which solidified with time drying at -20 degreeC to 5 degree-C / min.

<Storage stability>

Each ink composition was preserve | saved for 100 hours in the 50 degreeC thermostat, the sediment of fluorescent pigment was investigated, and the case where there was no sedimentation was evaluated as ((circle)) and the case where there was sedimentation as (x).

<Light resistance>

Each printed matter was irradiated with a fade meter for 5 hours, and the color change was observed by eye, and the case where there was no color change was evaluated as ((circle)) and the case where there was a color change as (x).

<Smeariness>

The bleeding of the printing surface of each printed matter was observed, and the case where there was no bleeding ((circle)) and the case where there was a bleeding were evaluated as (x).

<Dissolvability>

Each ink composition was dropped on a PET film, dried and solidified at room temperature for 24 hours, and alkaline water of pH 11 was added dropwise thereto, and redispersed was evaluated as (circle) and non-dispersed as (x).

<Transfer Characteristics>

20 printed matters were piled up, 5 kg weight was added to this, it was preserve | saved for 600 hours in the 30 degreeC thermostat, and it was set as ((circle)) which is non-transferring ((circle)). Table 1 below shows the results.

Storage stability Weather resistance Smearing Redissolution Transcription characteristics Example 1 Example 2 Example 3 Example 4 ○○○○ ○○○○ ○○○○ ○○○○ ○○○○ Comparative Example 1 Comparative Example 2 Comparative Example 3 ○ × ○ ○○ × × ○ × × ○○ ○ × ○

In addition, the emission spectrum of the printing surface of the printed matter obtained in Examples 5 and 6 and Comparative Examples 4 and 5 was measured using a spectrum measuring apparatus manufactured by Unisok. 4 and 5 show the results, FIG. 4 shows light emission spectra of the printing surface of the printed matter obtained in Example 5 and Comparative Example 4, and FIG. 5 shows the printed matter obtained in Example 6 and Comparative Example 5. The emission spectrum of the printing surface is shown.

As is clear from Figs. 4 and 5, although the infrared fluorescent dye used as a raw material is shifted to several tens of nm long wavelength side, it can be seen that the original infrared fluorescent dye is maintained.

Next, for the bar code printing of Japanese paper obtained in Examples 5 to 7 and Comparative Examples 4 to 5, the output of the reflection of the lower surface and the output of the infrared fluorescent mark of the bar code were obtained by high speed reading of 4 m / s with the detector shown in FIG. Measured under conditions. In this measurement, the output of the infrared fluorescent mark at the portion having a reflectance of 50% is set to C ₀ , the output of the infrared fluorescent mark at the portion having a reflectance of 50% is set to C ₁ , and the output of the infrared fluorescent mark at the portion having a reflectance of 10% is set to C ₀ . the C ₀ and the ratio and the ratio of the C ₂ and C ₁ a C ₁ to C ₂ when measured. In addition, each barcode was read for 100 samples, and the case where the read rate was 95% or more was evaluated as (circle), and the case where the read rate was less than 95% (x). Moreover, the printing was observed visually, and the case where it spreads was evaluated as (x) and the case where it did not spread as ((circle)).

Table 2 below shows the results.

Smearing C ₀ / C ₁ (%) C ₂ / C ₁ (%) Reading Example 5 Example 6 Example 7 ○○○ 2.52.52.8 15109 ○○○ Comparative Example 4 Comparative Example 5 Comparative Example 6 ×× ○ 2.42.62 0010 ×××

As is clear from Table 1, the ink compositions using the fluorescent organic pigments obtained in Examples 1 to 4 had good dispersion stability, and all of them printed with the ink compositions using the fluorescent organic pigments obtained in Examples 1 to 4 were all comparative examples. Ink compositions using fluorescent dyes of 1 to 3 have no bleeding and good light resistance and water resistance compared to printing and printing. According to the present invention, it is understood that a fluorescent ink composition having no bleeding and excellent dispersion stability, light resistance and water resistance is obtained. Can be.

In addition, as shown in Table 2, the infrared fluorescent marks (Examples 5 to 7) made of barcodes printed on Japanese paper in the present invention are infrared fluorescent marks made of barcodes printed on conventional Japanese paper (Comparative Examples 4 and 5). Compared with), there is no bleeding and the read rate is good, and from this, the infrared fluorescent mark according to the present invention is not affected by the dirt on the mark or the bleeding of the ink, and is not well influenced by the lower part of the mark. It can be seen that it is a stable high concentration of infrared fluorescent mark.

In addition, it can be seen that the infrared fluorescent marks of Examples 5 to 7 do not have a wrong operation even in high-speed reading as compared to the infrared fluorescent marks made of the inorganic fluorescent substance of Comparative Example 6, so that good reading is possible.

Claims (5)

Organic resin fine particles having a glass transition temperature of 30 DEG C or more and a particle diameter of 30 nm or more; Fluorescent dye is exhibited in the visible light wavelength range, containing 0.001% to 10% by weight relative to the weight of the organic resin fine particles, The organic resin is selected from the group consisting of polymethacrylic acid ester, polyacrylic acid ester, polyvinyl chloride, benzoguanamine resin, alkyd resin, urea resin, vinyl chloride, vinyl acetate copolymer, aromatic sulfonamide resin Fluorescent mark. The method of claim 1, The fine particle is a fluorescent mark comprising a hollow particle. Organic resin fine particles having a glass transition temperature of 30 DEG C or more and a particle diameter of 30 nm or more; Absorbs infrared light having a wavelength of 700 nm or more and emits light in the infrared wavelength region, and includes an infrared fluorescent dye containing 0.001% to 15% by weight based on the weight of the organic resin fine particles, The organic resin is selected from the group consisting of polymethacrylic acid ester, polyacrylic acid ester, polyvinyl chloride, benzoguanamine resin, alkyd resin, urea resin, vinyl chloride, vinyl acetate copolymer, aromatic sulfonamide resin Infrared fluorescent mark. The method of claim 3, Infrared fluorescent mark, characterized in that the fine particles comprise hollow particles. The method of claim 3, An infrared fluorescent mark characterized in that the rise time of 10% to 90% of the maximum light output when the mark is irradiated with infrared light is within 10 µsec.