JP2006274097A - Multicolored luminescent mixture, multicolored luminescent ink composition and image formation product - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a multicolored luminescent mixture that is obtained by mixing a plurality of ultraviolet excited pigments or visible light luminescent dyes having different excitation properties and luminescent wavelengths corresponding to ultraviolet radiation wavelengths and continuously changes luminescence according to irradiation wavelength of an ultraviolet range, a multicolored luminescent ink composition and an image formation product. <P>SOLUTION: The multicolored luminescent mixture is obtained by mixing at least three illuminants selected from illuminants in which a first illuminant, a second illuminant or a third illuminant which is luminescent by ultraviolet irradiation is selected from illuminants having main wavelengths in any of an R area, a G area or a B area of an RGB color display area and the illuminants luminescent in an R area, a G area and a B area selected from a first luminescent group, a second luminescent group and a third luminescent group in which the first luminescent group is at least one illuminant that is luminescent in an R area, the second luminescent group is at least one illuminant that is luminescent in a G area and the third luminescent group is at least one illuminant that is luminescent in a B area. The image formation product is provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  In the present invention, a plurality of UV-excited pigments or visible light-emitting dyes having different excitation characteristics and emission wavelengths depending on the UV irradiation wavelength are mixed in an ink vehicle, and light emission continuously changes according to the UV irradiation wavelength. The present invention relates to a multicolor luminescent mixture excellent in false discrimination, a multicolor luminescent ink composition in which the mixture is mixed with an ink vehicle, and an image formed product printed using the multicolor luminescent ink composition.

  Precious printed matter such as banknotes, securities, cards and tolls, and certificates that authenticate individuals such as driver's licenses, passports and insurance cards are always equipped with new anti-counterfeiting technology so that they are not counterfeited or tampered with by third parties There is a demand for a true / false discrimination method that can determine whether the product is genuine.

  A light emitter represented by a phosphor has at least two elements, ie, a light emission color (hue) and a light emission intensity as main authenticity determination elements. The hue is inherently unique, and the emission intensity of one is a value according to the amount of the illuminant. Therefore, by keeping the type and amount of the illuminant used constant, the hue in machine detection And true / false discrimination using the two of emission intensity.

  For example, the hue and emission intensity can be shown as waveforms on a graph with the emission wavelength on the X axis and the emission intensity on the Y axis in spectroscopic measurement. Since the shape of this waveform directly represents the hue and emission intensity, and the waveform is unique to each illuminant, it can also be determined by simply comparing this waveform obtained by spectroscopic measurement in authenticity determination. is there.

  In addition, as a simple method, only light in the wavelength region where the typical emission peak of the illuminant exists is extracted using a filter or diffraction grating (selection of hue), and photoelectric conversion (acquisition of luminescence intensity) is also judged. Is possible. Conventionally, in the mechanical determination of a light emitter, generally, there are many cases in which two of the hue and the light emission intensity are used as some authenticity determination element.

  However, hue and light emission intensity can be an excellent authenticity determination element when mechanically detecting a light emitter, but the opportunity to use the light emission intensity as a determination element in one of the visual sensory tests is very rare in practice. . This is because the sensory evaluation is a subjective evaluation and depends on the individual sense of the inspector, causing variations, and the intensity of light emission is greatly influenced by the environment at the time of observation.

  In many cases, mechanical inspection of illuminants generally uses a device that evaluates hue and luminescence intensity using a combination of photoelectric conversion elements, filters, and diffraction gratings. In any case, in order to avoid the influence of visible light In contrast, measurement is performed while blocking ambient light in a dark box, whereas sensory inspection is often performed in an environment where visible light is present.

  As an example, when measured using a spectrophotometer, even when observed in an environment where almost no visible light is inserted into a counterfeit printed material in which the emission intensity at the emission peak has dropped to an intensity of 1/3 or less, However, it is recognized as an extremely weak difference, and may be determined as an authentic product. It goes without saying that when visible light is inserted into the observation environment, the light emission of the illuminant is felt weaker, and the accuracy of the sensory test using the light emission intensity as a determination factor is further reduced.

  From this, even if the illuminant used in the counterfeit product is a illuminant different from the genuine product, if only the hue is the same, in a bright environment filled with sunlight or light from a fluorescent lamp, In sensory inspections such as ticket exchanges where fluorescent light emission must be confirmed only with black light, it may be indistinguishable from authentic products. As a discriminating element, there was a high possibility that it would not function.

  In view of this, there are cases where dichroic luminescent inks are used in which two types of light emitters are used for one ink and the hue is changed to two types according to the ultraviolet irradiation wavelength. The dichroic illuminant used in this ink is a combination of the long wave ultraviolet excitation type illuminant 1 and the short wave ultraviolet excitation type illuminant 2, and two colors are applied to one ink vehicle when inking. The light emitting material is dispersed and manufactured. As a feature, the long wave ultraviolet excitation type illuminant 1 emits light with a certain hue 1 when irradiated with ultraviolet long waves, and the long wave ultraviolet excitation type illuminant 1 and short wave when irradiated with ultraviolet short waves. When the ultraviolet-excited type illuminant 2 emits light at the same time, it emits a hue 2 that is different from the emission color at the time of ultraviolet long-wave irradiation.

  A general phosphor, emission color, and excitation characteristics are shown in FIG. As a typical example in which this dichroic luminescent material is applied to a base material, a French 500 franc ticket that emits colorless with visible light, red with ultraviolet shortwave, and green with ultraviolet shortwave is well known. There are printing colorless fluorescent light-emitting inks (see, for example, Patent Document 1) and colored dichroic light-emitting inks produced by the National Printing Bureau by mixing color pigments. In addition, as dichroic luminescent pigments, “LUMILUX CD-R / GI” of Honeywell Japan (red light emission by ultraviolet long wave, yellow light emission by ultraviolet short wave), “LUMILUX R / G CD770” (yellow light emission by ultraviolet long wave, DE-RB produced by Nemoto Special Chemical Co., Ltd. (blue light emission using ultraviolet long wave, red light emission using ultraviolet short wave), DE-RG (green light emission using ultraviolet long wave, red light emission using ultraviolet short wave), DE- GB (blue emission with ultraviolet longwave, green emission with ultraviolet shortwave), DE-GR (red emission with ultraviolet longwave, green emission with ultraviolet shortwave), etc. are known, and the user can select two hues arbitrarily Can be used.

  As described above, the dichroic luminescent material has two hues which are effective discrimination elements at the time of visual judgment, and the dichroic luminescent ink dispersed in one ink has authenticity discrimination. It is a new luminescent ink that has been improved, and since the hue is changed by two ultraviolet rays represented by ultraviolet shortwave and ultraviolet longwave, the discriminability in visual sensory inspection is expected to increase.

  In addition, in the case of mechanical inspection, until now, only one hue and emission intensity of either ultraviolet long wave or ultraviolet short wave, each having only two judgment elements, a total of two dichroic light emitters were provided. Since a total of four determination elements are provided, the determination suitability is naturally enhanced as compared with a monochromatic light-emitting body.

JP-A-10-251570

  The illuminant used for the dichroic illuminant has two types of illuminants and shows two hue changes. Therefore, the illuminant has a maximum fluorescence peak mainly due to ultraviolet shortwave (centered at 254 nm), and mainly illuminant. In general, the two light emitters are designed in combination of long light waves (centered at 365 nm), the light emitter having the maximum emission peak.

  Originally, there are not only two wavelengths of ultraviolet light that are excited by the illuminant, but it is roughly divided into ultraviolet short-wave excitation type and long-wave excitation type according to the emission line of the mercury lamp used for excitation. This is also related to the fact that many of the UV irradiation discriminating instruments possessed can only irradiate only the ultraviolet long wave region or the ultraviolet short wave region.

  The light region called ultraviolet rays exists over a wide range of 200 nm to 400 nm, but the wavelength between the ultraviolet long wave and the ultraviolet short wave, which are two typical representative wavelengths for the dichroic light emitter to show a change in hue, is 100 nm or more. Blank is present. The ultraviolet irradiation discrimination instrument used by many users is almost limited to this wavelength. Because of this, there is almost no chance of recognizing the difference regardless of what the dichroic illuminant emits at the blank wavelength, so the current dichroic illuminant is aimed at the time of ultraviolet longwave irradiation and ultraviolet shortwave irradiation. Designed to focus on.

  Considering this, the long-wave ultraviolet excitation type illuminant and the short-wave ultraviolet excitation type illuminant used for the dichroic illuminant should have the same hue only at the time of ultraviolet long-wave irradiation and ultraviolet short-wave irradiation. It is considered that it is determined to be authentic by visual sensory inspection. In this case, the hue at the ultraviolet longwave center wavelength (365 nm) and the ultraviolet shortwave center wavelength (254 nm) can be obtained without using the longwave ultraviolet excitation type illuminant and the shortwave ultraviolet excitation type illuminant used in the intrinsic product. If they match, it means that forgery is possible even when different types of light emitters having different excitation characteristics are used.

  These long-wave ultraviolet excitation type light emitters and short-wave ultraviolet excitation type light emitters used in this dichroic light emitter are already well known in the printing field where light emission printing is performed, and in addition to rough colors such as blue, red, and green. Several types of light emitters are sold by the light emitter manufacturers for each hue.

  In addition, long-wave ultraviolet-excited phosphors of various hues are now readily available at general merchandise stores, and short-wave ultraviolet-excited phosphors are becoming available. For this reason, a person who has a certain level of knowledge of the luminescent material is considered capable of forging the dichroic luminescent material. Of course, it is needless to say that it is easily reproducible for those skilled in the art involved in luminescent printing.

  In any case, it is considered that a dichroic illuminant that performs authenticity verification only in two wavelength regions of the ultraviolet region has a problem in using as a single authenticity determination element.

  Although it is difficult to forge and ink a dichroic illuminant as described above, it is relatively easy for skilled professionals including counterfeiters, even if it is more difficult than luminescent ink that emits single color light. was there.

  The present invention solves the above-mentioned problem, and specifically, in order to show high excitation characteristics at a long wave, a medium wave or a short wave, depending on the irradiation wavelength of the ultraviolet ray, any one of these ultraviolet rays is irradiated, At least three luminescent pigments or luminescent dyes that emit visible light in any of the R region, G region, and B region of the RGB color display region are mixed in an ink vehicle, and depending on the irradiation wavelength of ultraviolet rays, Visible light emission is possible with the mixed colors and RGB three primary colors that could not be obtained, and the multicolor light emission mixture excellent in authenticity discrimination in which the fluorescence emission changes continuously and the multicolor light emission produced by mixing it with the ink vehicle An object of the present invention is to provide an ink composition and an image formed by printing using the multicolor luminescent ink composition.

  The multicolor light-emitting mixture of the present invention is a multicolor light-emitting mixture formed by mixing at least three or more light emitters having different excitation characteristics by ultraviolet rays. At least one illuminant having a main wavelength of any one of the R region, G region, and B region of the region and having the main wavelength of the R region is a first luminescent group, and at least one luminescent material having the main wavelength of the G region , The second light emitting group, at least one light emitter having the dominant wavelength in the B region is the third light emitting group, and at least one light emitter having the dominant wavelength in the R region selected from the first light emitting group, At least one luminescent material having at least one luminescent material having a dominant wavelength in the G region selected from the luminescent group and at least one luminescent material having a dominant wavelength in the B region selected from the third luminescent group. UV When the light having the first wavelength in the region is irradiated, at least one of the mixed light emitters has the strongest emission intensity, and the first wavelength in the ultraviolet region is When light of different second wavelengths is irradiated, at least one of the mixed three or more light emitters has the strongest emission intensity, the first wavelength in the ultraviolet region, the second When irradiating with light having a third wavelength different from the wavelength of the first light emitter, the light emission intensity of at least one third light emitter is mixed so as to be the strongest among the at least three light emitters mixed. It is characterized by that.

  The multicolor luminescent mixture of the present invention is characterized in that it is selected from at least one phosphor or phosphor.

  The multicolor light emitting mixture of the present invention is characterized in that at least three light emitters are composed of inorganic light emitters or a combination of inorganic light emitters and organic light emitters. .

  The multicolor luminescent ink composition of the present invention is a multicolor luminescent ink composition obtained by mixing a multicolor luminescent mixture prepared by mixing three or more luminescent materials having different ultraviolet excitation characteristics into an ink vehicle. The light emitters that emit light when irradiated with ultraviolet rays each have at least one light emitter having a main wavelength in the R region, G region, or B region of the RGB display region, and having the main wavelength in the R region. The first light emitting group, at least one light emitter having a dominant wavelength in the G region is defined as a second light emitting group, and at least one light emitter having a dominant wavelength in the B region is defined as a third light emitting group. At least one light emitter having a main wavelength in the R region selected from the above, at least one light emitter having a main wavelength in the G region selected from the second light emitting group, and a main wavelength in the B region selected from the third light emitting group Of at least one illuminant having That is, at least one light emitter is mixed, and when the light having the first wavelength in the ultraviolet region is irradiated, light emission of at least one first light emitter among the mixed at least three light emitters. The emission intensity of at least one second light emitter among the at least three light emitters mixed when irradiated with light having the highest intensity and a second wavelength different from the first wavelength in the ultraviolet region. Is at least one of the mixed three or more light emitters when irradiated with light having a third wavelength different from the first wavelength and the second wavelength in the ultraviolet region. A multicolor luminescent mixture obtained by mixing so that the luminous intensity of the body is the highest is mixed with an ink vehicle.

  The image-formed product of the present invention is characterized in that a printed layer is formed using a multicolor luminescent ink composition.

  Because it has all three colors of RGB in additive color mixing, it was difficult for dichroic illuminants, depending on the combination of the “white” luminescence that cannot be developed with dichroic illuminants and the combination of illuminants used All colors including purple, indigo, blue, green, yellow, orange and red can be emitted.

  When a plurality of illuminants are excited simultaneously using a long-wave ultraviolet irradiation lamp, a medium-wave ultraviolet irradiation lamp, and a short-wave ultraviolet irradiation lamp by including RGB elements, the irradiation light quantity of each lamp and the lamp to the illuminant By changing the distance, the hue can be changed continuously like a rainbow.

  Needless to say, it is possible to distinguish all eight colors of “white” in addition to the seven main hues of “purple, indigo, blue, green, yellow, orange, red”. By fixing the irradiation light quantity of the ultraviolet irradiation lamp of the wavelength, or by fixing the distance between the lamp and the light emitter completely, it becomes possible to fix and identify the arbitrary hue determined by the user. Also, it is extremely effective in simple visual authentication considering rapidity.

  Even if only a simple sensory test (hue evaluation) is performed, one counterfeiter cannot narrow down in advance the wavelength regions used for authenticity determination, such as the conventional ultraviolet longwave region and ultraviolet shortwave region. Therefore, it can be said that it is extremely effective in improving counterfeiting and deterrence. (Medium-wave ultraviolet irradiation lamps that irradiate ultraviolet light with the central wavelength in the ultraviolet ultraviolet light region have been used as a nucleic acid emission confirmation lamp in the medical field. At present, since it is sold at almost the same price as the long wave ultraviolet irradiation lamp and the short wave ultraviolet irradiation lamp, there is no particular problem with the simple ultraviolet medium wave confirmation means).

  On the other hand, in the mechanical inspection, the conventional monochromatic illuminant and dichroic illuminant are used to determine whether the ultraviolet shortwave region centering on 254 nm or the ultraviolet longwave region centering on 365 nm is used. However, since this multicolor illuminant has complex and characteristic luminescent properties in any wavelength region of the ultraviolet region, monochromatic illuminants and dichroic illuminants. Then, it is possible to continuously obtain light emission in the entire ultraviolet region from 200 nm to 400 nm, which could not be a true / false discrimination target, and use all light emission as a determination element.

  Conventional illuminant authentication has been performed only in at least two wavelength regions, either 254 nm or 365 nm, or both. In other words, a two-dimensional form that is certified as a graph using the emission wavelength on the X-axis and the emission intensity on the Y-axis, and a three-dimensional hue space for the emission color with the ultraviolet excitation wavelength added to the Z-axis. As a matter of course, it is possible to introduce the concept of authenticating as follows, and it goes without saying that machine discrimination is remarkably enhanced as compared with the conventional case. Of course, as a simple determination, a limited method in which the user arbitrarily sets the ultraviolet irradiation wavelength region and the light receiving region for machine discrimination is possible.

  In the present invention using a plurality of different types of phosphors having different excitation characteristics, various combinations of hues and emission intensity can be adjusted according to the needs of the user, not only by the combination of the phosphors but also by the mixing ratio of the phosphors. At the same time, the forgery requires a technical level that cannot be compared with the conventional technology, so that the anti-counterfeiting effect and the anti-counterfeiting power are extremely high. In addition, due to the dramatic increase in the visual determination element and the machine determination element, authenticity discrimination is further enhanced.

  In the printed matter manufacturing process and the inspection process, the number of hues of the determination element is drastically increased, and the necessity of the concept of light emission intensity, which is one of the determination elements conventionally required in the printing process, is reduced. This means the management of the thickness of the printed film in conventional phosphor printing, and the hue of the phosphor itself is confirmed by checking a certain hue in the ink preparation stage to ensure the total hue. Since it can be managed, the quality control of the illuminant printing can be ensured only by an extremely easy method of confirming the ink application by the black light from the conventional method of quantifying the light emission intensity.

  In addition, for an authentic printer, in order to construct a print with a structure in which one image, image line, character, etc. emits multiple colors in the conventional technology, a single color is used after using three printing units. It is necessary to superimpose the three types of luminescent inks at the same position and superimpose them. If the image line or image is very small, its reproduction is extremely difficult. By producing an image line that emits multiple colors as a mixed ink, the number of printing units necessary for the production becomes one, and the problem of printing is also solved at the same time.

  In addition, when creating a light-emitting image, a light-emitting image line, or a light-emitting image having the same hue over the entire ultraviolet region by superimposing single light emitters in multiple layers, the case where the light-emitting layer is disposed above or below the light-emitting layer Since the light emission characteristics vary greatly depending on the varnish and the illuminant, obtaining an intended hue in the entire ultraviolet region requires extremely high technology and labor.

  The multicolor luminescent mixture of the present invention is prepared by mixing three or more phosphors having different ultraviolet excitation characteristics.

  Specifically, the first light emitter, the second light emitter, or the third light emitter that emits light when irradiated with ultraviolet rays has a main wavelength in any of the R region, the G region, and the B region of the RGB color display region. The first light emitter, the second light emitter, or the third light emitter is selected from at least one phosphor, and at least one light emitter that emits light in the R region is provided in the first light emitting group and the G region. At least one light emitter that emits light is a second light emission group, and at least one light emitter that emits light to the B region is a third light emission group. The first light emission group, the second light emission group, and the third light emission group The phosphor is produced by mixing at least three phosphors among the phosphors that emit light in the R region, the G region, and the B region selected from the inside.

  Furthermore, the emission intensity of one of the phosphors mixed at the first wavelength in the ultraviolet region is the strongest, and another one of the phosphors mixed at the second wavelength different from the first in the ultraviolet region. The phosphors are mixed so that the emission intensity of one of the mixed phosphors is the strongest at the third wavelength different from the first and second wavelengths in the ultraviolet region. Make it.

  Each light emitter used in the multicolor light emitting ink composition is selected from one of the light emitting groups belonging to the RGB region, and the three selected light emitters are mixed at the best mixing ratio for achieving the purpose.

  Confirmation of the effect of the produced multicolor light-emitting ink composition is a hue evaluation by irradiating ultraviolet rays. As ultraviolet irradiation means at that time, a long wave ultraviolet irradiation lamp (center wavelength 366 nm), a medium wave ultraviolet irradiation lamp (center wavelength 302 nm), and a short wave ultraviolet irradiation lamp (254 nm) are used.

  In general, light emitters tend to be broadly divided into two types: a long wave ultraviolet excitation type and a short wave ultraviolet excitation type, but in reality, they have excitation characteristics specific to each light emitter. As an example, a phosphor classified as a short wave ultraviolet excitation type emits little light in the ultraviolet long wave region and emits light only in the ultraviolet short wave region, but this is actually in the ultraviolet medium wave region. Some of them emit light rapidly, and others emit light rapidly only in the ultraviolet short wave region without emitting light in the ultraviolet medium wave region. In addition, light emitters that are simply classified as the long wave ultraviolet excitation type include those that emit light in the ultraviolet long wave region and emit light in the ultraviolet medium wave region and ultraviolet short wave region, those that do not change substantially, and those that emit more intensely.

  In addition, although organic light emitters often have problems with light resistance, they have light emission intensity that is not comparable to inorganic ones at the time of long-wave ultraviolet excitation, and the appropriate ultraviolet excitation wavelength region around the peak is narrow, Many of the light emission is attenuated. When the excitation characteristics including the difference in emission intensity are observed closely, it can be seen that the excitation characteristics are unique to each light emitter. When this difference in excitation characteristics is used, even the combination of illuminants that are generally classified as short-wave ultraviolet excitation types can be adjusted from the mid-ultraviolet region to the ultraviolet short-wave region by adjusting the blending amount. It is possible to produce a dichroic illuminant that has a remarkable hue change within half the wavelength of the same, and even in the case of a combination of illuminants of the long-wave ultraviolet excitation type, ultraviolet rays from the ultraviolet long-wave region It is also possible to produce a dichroic light emitter having a hue change up to the middle wave region.

  In this case, the combination of the short-wave ultraviolet excitation types can be realized by combining types having different long-wave excitation emission wavelengths, and the increase / decrease in the emission after the long-wave excitation emission can be used. The combination of different types of phosphors with different long-wave excitation emission wavelengths is a combination of an emitter with an excitation characteristic that emits light slowly from the ultraviolet midwave region and an emitter with a different excitation characteristic that emits light specifically in the ultraviolet shortwave region. By adjusting the composition, only one illuminant can emit light in the ultraviolet midwave region due to the difference in the long wave excitation emission wavelength, but as the ultraviolet emission wavelength becomes shorter, the other illuminant is also excited rapidly and gradually. The emission color becomes a mixed color of two colors. In this way, the final emission color can be arbitrarily adjusted by adjusting the mixing ratio of the two light emitters.

  Further, as a combination of the long wave ultraviolet excitation types, it is also possible to use the difference in the long wave excitation wavelength and the increase / decrease in the light emission after the long wave excitation light emission as in the ultraviolet short wave type. As an example, as a combination using increase / decrease in light emission after the initial light emission, an organic light emitter whose light emission intensity decreases at once after light emission and an inorganic light emitter whose light emission intensity is almost constant with respect to a change in ultraviolet wavelength are combined. There are cases.

  Since the two light emitters are excited almost simultaneously, the initial light emission is a color mixture of the colors emitted by the two light emitters. The light emission of the illuminant is dominant. However, since the emission intensity of the organic luminescent material decreases at a stretch in the subsequent region, the luminescence of the inorganic luminescent material becomes dominant. Thus, the same hue change can be obtained by using the light emitters having different hues for the organic light emitter and the inorganic light emitter, respectively.

  As an example, a combination of an organic system and an inorganic system has been described. However, if the excitation characteristics are greatly different, this can be realized by adjusting the blending with a combination of inorganic phosphors. These are special dichroic light emitters that can make a characteristic hue change within a very limited range of 50 nm or less even when compared with a conventional dichroic light emitter having a light emitting blank of about 100 nm. .

  The present invention is not limited to the special dichroism described in the conventional dichroism, but by combining three or more different light emitters, various hue expressions for sensory inspection and complicated and diverse for mechanical inspection. A wide range of UV wavelengths that have not been considered so far, rather than designing luminescent mixtures in the broad classification of long-wave ultraviolet excitation types and short-wave ultraviolet excitation types as in the past. A combination of a plurality of light emitters is considered in consideration of the fine excitation characteristics unique to each light emitter over a region, and the excitation characteristics of the individual light emitters mixed in a complicated manner. The present invention relates to a light-emitting body excellent in authenticity determination in which light emission that becomes dominant appears as a hue at the ultraviolet wavelength.

  In addition, when the purpose is to improve machine discrimination like identification information, the emission color that can be visually confirmed by selecting a light emitter of the same hue is not changed intentionally, and only the emission waveform at the time of spectroscopic measurement is used. Needless to say, a special machine-read-only ink with characteristic changes is sufficient, and it can be implemented simply by reducing the effect of the invention.

  As an example, initial light emission in the ultraviolet wavelength region of 300 nm or less, and then, in the ultraviolet wavelength region of 320 nm ultraviolet light and the green light emitter 1 having an excitation characteristic that significantly increases the emission intensity when the excitation wavelength is shifted to the short wavelength side, Thereafter, even when the excitation wavelength is shifted to the long wavelength side, the red light emitting element 2 having an excitation characteristic that hardly changes the emission intensity, emits light in the long wave ultraviolet excitation region, and then the excitation wavelength is further shifted to the long wavelength side. In the case of a mixed illuminant obtained by mixing three illuminants of the purple illuminant 3 having an excitation characteristic that does not change the emission intensity, the problem that the dichroic illuminant has so far been completely overcome. Becomes a light emitter.

  Assuming that the user performs true / false judgment only in the three-wavelength excitation region of ultraviolet longwave, ultraviolet ultraviolet medium wave, and ultraviolet shortwave, as a simple hue check for true / false discrimination, a third party can only check the excitation region. Assume that a counterfeit product that can be determined to have the same hue is manufactured.

  In the case of this multicolor illuminant, the excitation wavelength interval at the ultraviolet excitation wavelength of each illuminant is about 50 nm, which is almost half of the dichroic illuminant utilizing the conventional two-wavelength excitation region of ultraviolet long wave and ultraviolet short wave. In addition, only the violet light emitter 3 emits light in the long wave ultraviolet excitation region, the mixed color of the red light emitter 2 and the light emitter 3 in the medium wave ultraviolet excitation region, and the light emitter 1 in the short wave ultraviolet excitation region. Since the light emitting body 2 and the light emitting body 3 are all mixed colors, changing the type of the light emitting body 1 or the light emitting body 2 has a great influence on the color development in the medium wave ultraviolet excitation region or the short wave ultraviolet excitation region. Will be affected.

  In this case, it is likely that the illuminant 1 that emits light only in the short-wave ultraviolet excitation region does not affect the hue and light emission intensity in other wavelength excitation regions, and can adjust the hue and light emission by itself. Actually, this also has already been emitted with excitation light having a wavelength longer than 320 nm, so that it appears as a difference in hue and emission intensity in the medium-wave ultraviolet excitation region.

  In this way, in the wavelength region on the short wavelength side after the medium-wave ultraviolet excitation region, the light emission of different types of light emitters is a mixed color intricately intertwined, so three limited excitation wavelength regions in the ultraviolet excitation wavelength Even when trying to make the hues coincide with each other, it is extremely difficult to completely imitate the hue as compared with the conventional dichroic light emitter.

  As described above, in order to reproduce a counterfeit product that emits the same three hues as the genuine product, it is necessary to use an illuminant having almost exactly the same excitation characteristics. Since there are no different types of illuminants with the same hue and perfectly matched UV excitation characteristics, the same illuminant as that of the genuine product is required for reproduction.

  Further, even in the case of a combination of genuine luminescent materials, if the blending ratio is different, a hue that does not match in any ultraviolet excitation wavelength region appears, and thus a high technical level is required for its reproduction.

  In the best mode for carrying out the present invention, the following four examples will be described. Regarding Example 1 and Example 2, it is a multicolor light emitting ink composition prepared by mixing three kinds of light emitters, and a great effect can be obtained by visual hue evaluation using a general ultraviolet irradiation device. It is. Moreover, regarding Example 3, it is a multicolor light emitting ink composition prepared by mixing three kinds of light emitters, and a great effect can be obtained by hue evaluation using a special ultraviolet irradiation device used for machine reading. It is. Further, Example 4 is a multicolor light-emitting ink composition prepared by mixing four types of light emitters by adding another type of light emitter to the light emitter used in Example 3, and for machine reading. A great effect can be obtained by hue evaluation using a special ultraviolet irradiation device to be used, and a great effect can also be obtained by visual hue evaluation using a general ultraviolet irradiation device.

  An example of the embodiment of the present invention when the visual hue change is increased with respect to the change of the ultraviolet irradiation wavelength is shown. In this case, it is assumed that the user simply determines the hue by irradiating a lamp in the ultraviolet long wave region, the ultraviolet medium wave region, and the ultraviolet short wave region. The individual light emitters used for the multicolor light emitter are roughly selected from each of the light emitting groups belonging to the RGB region, and the selected three kinds of light emitters are mixed. The selection of the luminescent pigment that can maximize the hue change was performed as shown in FIG. In order to maximize the intended hue change, the B-based luminous body 1 was selected as the luminous body 1 having the lowest wavelength in the visible region and having a violet emission peak of 440 nm. FIG. 3A shows the relationship (excitation characteristics) between the ultraviolet irradiation wavelength of the luminous body 1 and the emission intensity at the emission peak. Moreover, it shows in FIG.3 (b) about the light emission wavelength and light emission peak of the light-emitting body 1. FIG. The illuminant 1 is generally classified into a long wave ultraviolet excitation type, but is an illuminant having an excitation characteristic that emits purple light at an ultraviolet long wave of about 380 nm and whose emission intensity does not substantially change even when irradiated with ultraviolet light having a shorter wavelength. .

  Subsequently, as the R-based illuminant 2, the illuminant 2 having the maximum wavelength in the visible region having an emission peak of 650 nm in red was selected. FIG. 4A shows the relationship (excitation characteristics) between the ultraviolet irradiation wavelength of the luminous body 2 and the emission intensity at the emission peak. Moreover, it shows in FIG.4 (b) about the light emission wavelength and light emission peak of the light-emitting body 2. FIG. The illuminant 2 is generally classified as a short-wave ultraviolet excitation type, but emits red light at about 330 nm of ultraviolet light, and emits light having an excitation characteristic that does not substantially change the emission intensity when irradiated with ultraviolet light having a shorter wavelength. Is the body.

  Subsequently, the green light emitter 3 having a light emission peak of 520 nm in green was selected as the G-based light emitter 3. FIG. 5A shows the relationship (excitation characteristics) between the ultraviolet irradiation wavelength of the luminous body 3 and the emission intensity at the emission peak. Moreover, it shows in FIG.5 (b) about the light emission wavelength and light emission peak of the light-emitting body 3. FIG. The illuminant 3 is generally classified into a short wave ultraviolet excitation type, but is an illuminant having an excitation characteristic that specifically emits green light in a short wave region shorter than the ultraviolet short wave of 300 nm.

  As in this example, when the illuminant is intended to exhibit a drastic hue change according to the ultraviolet irradiation wavelength, conditions for selecting the illuminant 1, the illuminant 2, and the illuminant 3 are necessary. come. As the selection condition, it is desirable that the luminous intensity does not increase at least greatly even when the light emitting body 1 is excited by the ultraviolet long wave 365 nm and then the irradiation wavelength shifts to a short wavelength in the ultraviolet medium wave region or the ultraviolet short wave region. When the light emission intensity of the light emitter 1 increases below the ultraviolet long wave region, it changes to a hue that overlaps with the hue of the light emitters 2 and 3 that emit light in the ultraviolet medium wave region and the ultraviolet short wave region. Therefore, it is preferable to use a light emitter that emits light with a reduced intensity at a wavelength shorter than 365 nm, which is the ultraviolet long wave authentication region.

  It is desirable that the illuminant 2 is not characterized by being excited by long wave ultraviolet rays, and it is desirable that the light emission intensity is not greatly increased by short wave ultraviolet rays. Similar to this problem, the emission colors purple and red are mixed when irradiated with long-wave ultraviolet light, and red and green are mixed when irradiated with short-wave ultraviolet light. It is also for avoiding that the visibility of a change falls.

  It is desirable that the light emitter 3 is not excited by long wave ultraviolet light and medium wave ultraviolet light. As with the light emitter 1 and light emitter 2, when green light is emitted when irradiated with long wave ultraviolet light or medium wave ultraviolet light, it is mixed with violet light and red light emission. This is a necessary property to prevent the light emission of purple or red light during medium wave excitation from being ambiguous.

  After selecting phosphor groups with different excitation characteristics and hues, each pigment content was examined. Considering practicality such as ink suitability, printing workability, and fastness of printed matter, the ratio of the pigment in the ink is often limited. Therefore, the total of luminous body 1, luminous body 2, and luminous body 3 The total weight of the light-emitting body 1, the light-emitting body 2, and the light-emitting body 3 is finely adjusted in consideration of the balance of hue. It was a method. In mixing a small amount of light emitters, a multicolor light emitter in a uniformly dispersed state was simply mixed using a mortar or the like until the light emitters were uniform.

  First, a multicolor light emitting body in which 10 parts by weight of each of the light emitting body 1, the light emitting body 2, and the light emitting body 3 shown in FIG. 1 are mixed together is manufactured, and the hue when the wavelength of ultraviolet rays to be irradiated is changed over a wide range. The change of was confirmed. As an ultraviolet irradiation means for confirming the effect, a long wave ultraviolet irradiation lamp (center wavelength 366 nm), a medium wave ultraviolet irradiation lamp (center wavelength 302 nm), and a short wave ultraviolet irradiation lamp (center wavelength 254 nm) were used.

  As a result, the purple coloration when irradiated with long-wave ultraviolet rays has a sufficient degree of recognition, but when the medium-wave ultraviolet rays are irradiated, the red coloration of the light emitter 2 is weak and mixed with the blue light emission of the phosphor 1. It was recognized as bluish purple, and the light emission colors of the light emitter 1, light emitter 2, and light emitter 3 were mixed when irradiated with short-wave ultraviolet light, resulting in light emission as almost perfect white.

  In consideration of this result, the second prototype group of FIG. 6 consisting of Sample 1 to Sample 4 having different blending ratios was produced. First, for sample 1, 10 g of the light emitter 1, 5 g of the light emitter 2, and 15 g of the light emitter 3 were mixed to produce a multicolor light emitter. For sample 2, a multicolor light emitter was prepared by mixing 10 g of the light emitter 1, 15 g of the light emitter 2, and 5 g of the light emitter 3. Regarding sample 3, a multicolor light emitter was prepared by mixing 5 g of the light emitter 1, 15 g of the light emitter 2, and 10 g of the light emitter 3. For sample 4, a multicolor light emitter was prepared by mixing 5 g of the light emitter 1, 10 g of the light emitter 2, and 15 g of the light emitter 3. Subsequently, as a result of visual evaluation of the hue of the illuminant at the time of long-wave ultraviolet irradiation (center wavelength 366 nm), medium-wave ultraviolet irradiation (center wavelength 302 nm), and short-wave ultraviolet irradiation (center wavelength 254 nm), FIG. It became as follows.

  In any of these, the luminescence change by different kinds of illuminants having different excitation characteristics, which is the essence of the present invention, is sufficiently provided, and the hue change of the luminescent color is sufficient for machine discrimination. In this example, the purpose was to increase the hue change, so the formulation was readjusted. Since the evaluation of the hue change of Sample 3 and Sample 4 was high, finally, the best blending ratio was determined by finely adjusting the pigment blending ratio in units of several percent based on these two.

  FIG. 8 shows the best blending ratio of the illuminant 1, the illuminant 2 and the illuminant 3, and FIG. 9 shows the result of the hue evaluation when each of the multicolor illuminants produced thereby is irradiated with ultraviolet rays. . The target effect is obtained by emitting purple when irradiated with long-wave ultraviolet light (center wavelength 366 nm), red when irradiated with medium-wave ultraviolet light (center wavelength 302 nm), and green when irradiated with short-wave ultraviolet light (center wavelength 254 nm). Confirmed that.

  FIG. 10 (a) shows the light emission distribution upon excitation of the long wave ultraviolet light, FIG. 10 (b) shows the light emission distribution upon excitation of the medium wave ultraviolet light, and FIG. 10 (c) shows the spectral distribution upon excitation of the short wave ultraviolet light.

  The emission intensity on the Y axis of the graphs of FIGS. 10 (a), 10 (b), and 10 (c) is a relative intensity, and the maximum peak on the waveform is about 80% on the graph. These were confirmed to have a peak wavelength sufficient for mechanical detection even in a spectrophotometer (manufactured by Hitachi, Ltd., model 850 spectrofluorometer).

  In addition, the distance between each ultraviolet irradiation lamp and the multicolor illuminant to reproduce the entire hue was investigated. FIG. 11 shows the positional relationship among the multicolor light emitter (1), the long wave ultraviolet irradiation lamp (2), the medium wave ultraviolet irradiation lamp (3), and the short wave ultraviolet irradiation lamp (4). In the positional relationship, the hue was evaluated by changing the distance between the multicolor illuminant (1) and each of the ultraviolet irradiation lamps (2), (3), and (4) into eight patterns. The result of the hue evaluation is shown in FIG. From this result, by changing the distance of each ultraviolet irradiation lamp with respect to this light emitter, in addition to reproducing the entire hue, it is possible to emit white light that was impossible with conventional monochromatic light emitters and dichroic light emitters. I was able to confirm that there was. Since the irradiation light quantity is inversely proportional to the square of the distance, it is needless to say that the hue change can be confirmed by increasing or decreasing the irradiation light quantity while keeping the distance of each ultraviolet lamp constant.

  After producing a multicolor illuminant, an ink vehicle was subsequently selected to make it into an ink. Since ink vehicles used in printing methods such as gravure printing, flexographic printing, letterpress printing, offset printing, and screen printing are all made of organic matter, they originally have the property of absorbing ultraviolet rays.

  All organic compounds containing halogen, carbonyl group, benzene ring, unsaturated group, etc. have a characteristic of absorbing ultraviolet rays, but salicylic acid type absorbers, benzophenone type ultraviolet absorbers, benzotriazole type ultraviolet absorbers Cyanoacrylate-based ultraviolet absorbers are representative, and benzotriazole-based ultraviolet absorbers are known to have remarkable absorption characteristics even in the ultraviolet longwave region.

  Polyurethane resin, polyurea resin, polyamide resin, polyester resin, polycarbonate resin, aminoaldehyde resin, melamine resin, polystyrene resin, acrylic resin, styrene acrylic copolymer, gelatin, polyvinyl alcohol, etc. are also in the ultraviolet shortwave region of the ultraviolet region. In particular, it is known to have a characteristic of absorbing light of a short wavelength.

  In this example, since the purpose is to show the hue at each wavelength clearly, it is desirable to avoid an ink vehicle having a characteristic of strongly absorbing only a certain wavelength in ultraviolet rays.

  In this embodiment, the water-based styrene acrylic varnish used in gravure printing is used. However, the selection of the ink vehicle should be designed in consideration of the printing method desired by the user. If the ink vehicle to be used is limited to those having high absorption characteristics of short-wave ultraviolet rays, the mixing ratio of the light emitter 3 in the ink is increased in consideration of the attenuation of light emission of the light emitter 3 Therefore, the printing method is not limited.

  Finally, a multicolor luminescent ink composition for gravure printing was prepared with the ink composition shown in FIG. The pigment is 30 parts by weight, and after adding the multicolor illuminant to the ink vehicle, 2 parts by weight of a silicon-based antifoaming agent is added as an auxiliary agent. The mixture was re-stirred at a maximum rotational speed of 3000 rpm for 3 minutes using a homodisper manufactured by Homo Disper) to make an ink. Using this gravure lithographic testing machine (GP-2 type manufactured by Kurabo Industries Co., Ltd.), gravure printing is performed at 175 lines / inch using a non-fluorescent gravure printing paper manufactured by the National Printing Bureau, and the intended printed matter Got.

  Since this ink composition is white under visible light and white coated paper is the base, the invisible image structure cannot be specified by visual confirmation. When the hue was confirmed by the same method as the hue confirmation of the multicolor illuminant, it was confirmed that the effect of the multicolor illuminant could be exhibited without impairing the hue of the illuminant.

  Another example of the implementation of the present invention in the case where an organic pigment is used for the light-emitting body for the purpose of high visual recognition performance will be shown. Since the emission intensity of inorganic luminescent pigments is lower than the emission intensity of organic luminescent pigments, when only inorganic luminescent pigments are used in the entire luminous body group, ink is used to satisfy the luminescent intensity required by users. In some cases, a high pigment mixing ratio exceeding 30% may be unavoidable, and depending on the printing method, the printing suitability unsuitable for continuous printing may be inferior, and the fastness of the printed matter may be lowered. In the case of the present invention, in order to develop a plurality of hues in a complicated manner, the total phosphor pigment content may be high, so that at least one of the phosphor groups is an organic compound having a high emission intensity. This is an example in which the use of a pigment reduces the content of the total luminescent pigment in the final multicolor luminescent ink, thereby improving the printability.

  As in the first embodiment, the ultraviolet irradiation wavelength region used for authenticity determination by the user is assumed to be only three limited ranges in which a long wave region, a medium wave region, and a short wave region can be easily determined. The light emitters used in the same manner as in Example 1 were selected from each of the light emitting groups belonging to the RGB region, and three types of light emitters having different hues were mixed. As in Example 1, the selection of the luminescent pigment was performed as shown in FIG.

  FIG. 15A shows the relationship between the ultraviolet irradiation wavelength of the G-based light emitter 4 and the emission intensity at the emission peak. Further, FIG. 15B shows the emission wavelength and emission peak of the luminous body 4. The illuminant 4 is an organic illuminant classified as a long wave ultraviolet excitation type having an emission peak of 520 nm, and emits green light at an ultraviolet long wave of 380 nm and emits ultraviolet light having a wavelength shorter than that. Is an illuminant having an excitation characteristic that decreases rapidly. Organic phosphors are inferior in light resistance compared to inorganic phosphors, but the emission intensity is extremely high, and light emission is significantly reduced in the mid-wave ultraviolet region and short-wave ultraviolet region after emitting light in the long-wave ultraviolet region. Therefore, as long as it satisfies the characteristics required by the user in terms of robustness and light resistance, it has preferable characteristics for use as a long wave ultraviolet excitation type light emitter constituting the present invention. ing.

  Subsequently, a blue light-emitting body 5 having an emission peak having a wavelength of 480 nm was selected as the B-based light-emitting body 5. FIG. 16A shows the relationship between the ultraviolet irradiation wavelength of the luminous body 5 and the emission intensity at the emission peak. Further, FIG. 16B shows the emission wavelength and emission peak of the luminous body 5. The illuminant 5 is an illuminant classified as a short-wave ultraviolet excitation type and emits blue light in the ultraviolet mid-wave region of 310 nm, and emits light having an excitation characteristic that does not substantially change the emission intensity when irradiated with ultraviolet light having a shorter wavelength. Is the body.

  Subsequently, a red light emitter 6 having an emission peak with a wavelength of 620 nm was selected as the R light emitter 6. FIG. 17A shows the relationship between the ultraviolet irradiation wavelength of the luminous body 6 and the emission intensity at the emission peak. In addition, FIG. 17B shows the emission wavelength and emission peak of the luminous body 6. The illuminant 6 is an illuminant classified into a short wave ultraviolet excitation type, and is an illuminant having excitation characteristics that specifically emits red light at a wavelength shorter than 300 nm in the ultraviolet short wave region.

  The conditions for selecting the light emitter 4, the light emitter 5, and the light emitter 6 are required to have the same characteristics as those of the light emitter 1, the light emitter 2, and the light emitter 3 of the first embodiment. After selecting the phosphor groups having different excitation characteristics and hues, the pigment content was examined in the same manner as in Example 1.

  The best mixing ratio is shown in FIG. Since the phosphor 4 which is an organic pigment has a very strong emission intensity compared to the phosphor 5 and the phosphor 6 which are inorganic pigments, the blending ratio is very low, and as a result, It is possible to obtain an effect of reducing the total pigment content of the multicolor luminescent material.

  Further, since the light emitter 4 emits light significantly in the ultraviolet medium wave region and the ultraviolet short wave region, it does not emit light when the medium wave ultraviolet light is excited and when the short wave ultraviolet light is excited. Can be emitted almost as is.

  As for the ultraviolet irradiation means for confirming the effect, a long wave ultraviolet irradiation lamp (center wavelength 366 nm), a medium wave ultraviolet irradiation lamp (center wavelength 302 nm), and a short wave ultraviolet irradiation lamp (center wavelength 254 nm) were used as in Example 1.

  When this multicolor illuminant is irradiated with ultraviolet rays of various wavelengths, it emits green light when irradiated with long-wave ultraviolet light, blue light when irradiated with medium-wave ultraviolet light, and orange light when irradiated with short-wave ultraviolet light to obtain the intended effect. It was confirmed. The hue evaluation is shown in FIG.

  FIG. 18A shows the light emission distribution when the long wave ultraviolet light is excited, FIG. 18B shows the light emission distribution when the medium wave ultraviolet light is excited, and FIG. 18C shows the spectral distribution when the short wave ultraviolet light is excited. All of these were measured using a spectrophotometer (850 type spectrofluorimeter manufactured by Hitachi, Ltd.). The emission intensity on the Y-axis of the graph of FIG. 8 is a relative intensity, and the maximum peak on the waveform is about 80% on the graph. As a result, it was confirmed that the peak wavelength was sufficient for machine detection in any wavelength region.

  In addition, the distance between the ultraviolet irradiation lamp and the multicolor light emitter for reproducing the whole hue was investigated. The positional relationship among the multicolor illuminant (1), the long wave ultraviolet irradiation lamp (2), the medium wave ultraviolet irradiation lamp (3), and the short wave ultraviolet irradiation lamp (4) is shown in FIG. It was as follows. In the positional relationship, the hue was evaluated by changing the distance between the multicolor illuminant (1) and each of the ultraviolet irradiation lamps (2), (3), and (4). The result of the hue evaluation is shown in FIG. In this example, the emission peak of the selected G-based illuminant is 480 nm, and the red emission peak is 620 nm, which is orange. Therefore, the purple, indigo and red hues cannot be emitted, but white emission is possible. I was able to get it.

  From this result, in addition to reproduction of hues other than purple, indigo and red by changing the distance of each ultraviolet irradiation lamp with respect to this printed matter, it was impossible with conventional monochromatic light emitters and dichroic light emitters. It was confirmed as in Example 1 that white light emission was possible.

  In this example, the organic light emitter is used only for the long wave ultraviolet excitation type light emitter 4, but there is no problem whether it is used for the light emitter 5 or the light emitter 6. Needless to say, the present invention can be implemented even if a plurality of organic light emitters are used as long as the excitation characteristics and the light resistance match those intended by the user.

  With this pigment ratio, a gravure ink was prepared in the same manner as in Example 1. In order to obtain a colored luminescent ink even under visible light, the ink composition was finally made into an ink by the same method as in Example 1 with the ink composition shown in FIG. 22 to which 1% of phthalocyanine blue 5G was added. Using this gravure lithographic testing machine (GP-2 type, manufactured by Kurabo Industries Co., Ltd.), the printed matter intended for gravure printing at 175 lines / inch using non-fluorescent printing coated paper manufactured by the National Printing Bureau Got.

  Since this ink is light blue under visible light and white coated paper is the base, a visible image configuration is obtained in which the printing position can be specified in visual confirmation. When the hue was confirmed by the same method as the hue confirmation of the luminescent material, the emission intensity was slightly reduced by using the color pigment, but the hue itself was not impaired, and the effect of the multicolor luminescent material was exhibited. It was confirmed that it was made.

  An example of the present invention having a hue change in a limited range from the ultraviolet long wave region to the ultraviolet medium wave region is shown. The multicolor illuminant in this example changes the hue of BGR in a very narrow region from 400 nm to 300 nm of long wave ultraviolet light to medium wave ultraviolet light.

  The ultraviolet irradiation apparatus currently on the market is generally a long wave ultraviolet irradiation lamp such as a black light centering on 365 nm and a short wave ultraviolet irradiation lamp used for a germicidal lamp centering on 254 nm. There is also a medical medium wave ultraviolet irradiation lamp centering around 302 nm. Since the emission lines of mercury lamps and xenon lamps used in these are distributed over a wide range, the ultraviolet wavelengths to be irradiated are mixed with various ultraviolet wavelengths that deviate from the central wavelength. It does not irradiate only the central wavelength.

  In addition, ultraviolet irradiation LEDs, which have been spreading in recent years as compact ultraviolet irradiation means, can irradiate in an area where the irradiation wavelength is sharper than that of the lamp, but the minimum wavelength is about 360 nm, and currently the ultraviolet wavelength range is less than that. Is not available.

  On the other hand, a spectrophotometer used for machine reading can measure by narrowing down to an ultraviolet irradiation range of several nm span by combining a low-pressure mercury lamp, a xenon lamp and a diffraction grating. In Example 1 and Example 2, in consideration of the user's authenticity, the design is such that the hue change is felt most greatly when an ultraviolet irradiation lamp that is generally easily available is irradiated. In general, a lamp with a wide irradiation area sold has a small color change. On the other hand, the authenticity by a spectrophotometer used for machine reading, or a simple lamp when only a special irradiation device is used. The purpose was to make a hue change that was not possible. This is a special authentication type that uses light emission as the identification information.

  The individual light emitters used for the multicolor light emitter are selected from each of the light emitting groups belonging to the RGB region, and three kinds of light emitters are mixed. The selection of the three types of luminescent pigments was as shown in FIG. As the B-based illuminant, the illuminant 7 having the lowest wavelength in the visible region having an emission peak of 440 nm in purple was selected. FIG. 24A shows the relationship (excitation characteristics) between the ultraviolet irradiation wavelength of the light emitter 7 and the light emission intensity at the light emission peak. FIG. 24B shows the emission wavelength and emission peak of the luminous body 7. The illuminant 7 is an organic illuminant and is generally classified as a long wave ultraviolet excitation type. However, the illuminant 7 emits violet light specifically at about 380 nm in the ultraviolet long wave region, and emits significantly when irradiated with ultraviolet light having a shorter wavelength. It is an illuminant with an excitation characteristic that attenuates.

  Next, the green light emitter 8 having an emission peak of 540 nm in green was selected as the G-based light emitter. FIG. 25A shows the relationship (excitation characteristic) between the ultraviolet irradiation wavelength of the light emitter 8 and the emission intensity at the emission peak. Further, FIG. 25B shows the emission wavelength and emission peak of the luminous body 3. The illuminant 8 is generally classified into a long wave ultraviolet excitation type, but is an illuminant having an excitation characteristic in which the emission intensity does not change from a long wavelength region to a short wavelength region.

  Next, as the R-based illuminant, the illuminant 9 having the maximum wavelength in the visible region having an emission peak of 650 nm in red was selected. FIG. 26A shows the relationship (excitation characteristic) between the ultraviolet irradiation wavelength of the luminous body 9 and the emission intensity at the emission peak. In addition, the emission wavelength and emission peak of the light emitter 2 are shown in FIG. The light emitter 9 is generally classified as a short wave ultraviolet excitation type, but emits red light in the ultraviolet midwave region of about 330 nm and emits light having an excitation characteristic that does not substantially change the emission intensity when irradiated with an ultraviolet wavelength shorter than that. Is the body.

  In the present example that assumes authentication under the limited conditions of the multicolor illuminant, the selection conditions of the illuminant 7, the illuminant 8, and the illuminant 9 are the same as in the first and second examples. However, the same properties as those of the light emitter 1, the light emitter 2, and the light emitter 3 are required. After selecting the phosphor groups having different excitation characteristics and hues, the pigment content was examined in the same manner as in Examples 1 and 2.

  Based on the result, the best mixing ratio is shown in FIG. Moreover, the result of the hue evaluation for every ultraviolet irradiation wavelength is shown to Fig.28 (a), (b). FIG. 28A shows a hue evaluation result when a special irradiation apparatus is used as a hue evaluation confirmation means, and FIG. 28B shows a case where a general irradiation apparatus is used as a hue evaluation confirmation means. The hue evaluation results are shown.

  First, as a special irradiator, using a spectrophotometer irradiator (xenon lamp and diffraction grating), the hue that appears in the polychromatic light emitter when the irradiation wavelength is divided into 5 nm spans is visually observed. The confirmed result is shown in FIG. From this result, it was confirmed that the reproduction of the hue including the halftone from blue to orange occurred in a limited wavelength region from 400 nm to 300 nm.

  For comparison with this result, the hue was evaluated using a general ultraviolet irradiation lamp in the same manner as in Example 1 and Example 2. As ultraviolet irradiation means for confirming the effect of hue evaluation, a long wave ultraviolet irradiation lamp (center wavelength 366 nm), a medium wave ultraviolet irradiation lamp (center wavelength 302 nm), and a short wave ultraviolet irradiation lamp (center wavelength 254 nm) are used. The reproduction results were compared. Blue in long wave ultraviolet rays, yellow in medium wave ultraviolet rays, and orange in short wave ultraviolet rays, but the green hue which is one of the three main hues of RGB should be confirmed using a simple irradiation lamp. It was impossible to confirm that the intended effect was obtained.

  FIG. 29A shows a light emission distribution at the time of long-wave ultraviolet excitation (center wavelength 365 nm), FIG. 29B shows a light emission distribution at the time of long-wave ultraviolet excitation (center wavelength 340 nm), and FIG. The spectral distribution of the central wavelength (302 nm) is shown. The emission intensity on the Y axis of each graph is a relative intensity, and the maximum peak on the waveform is about 80% on the graph. These are measured using a spectrophotometer (850 type spectrofluorometer manufactured by Hitachi, Ltd.), and as a result, it can be confirmed that they have a sufficient emission peak for mechanical detection in any wavelength range. It was.

  After producing a multicolor illuminant, an ink vehicle was selected to make it into an ink. In the same manner as in Example 1 and Example 2, a multicolor light-emitting ink composition for gravure printing was finally prepared with the ink formulation shown in FIG. After adding 30 parts by weight of pigment and 70 parts by weight of ink vehicle and adding the multicolor light emitter to the vehicle for ink ink, a silicon-based antifoaming agent is added in an extra 2% portion as an auxiliary agent. Using a special machine industry (Homo disperser), the mixture was re-stirred for 3 minutes at a maximum rotational speed of 3000 rpm to produce ink. Using this gravure lithographic testing machine (GP-2 type, manufactured by Kurabo Industries Co., Ltd.), the printed matter intended for gravure printing at 175 lines / inch using non-fluorescent printing coated paper manufactured by the National Printing Bureau Got.

  Since this ink is white under visible light and the white coated paper is the base, the print position cannot be specified by visual confirmation. When the hue was confirmed by the same method as the hue confirmation of the illuminant, it was confirmed that the effect of the multicolor illuminant could be exhibited without impairing the hue.

  An example in which different types of illuminants are added to the multicolor illuminant of Example 3 to form four types of illuminants, the hue is changed, and emission changes suitable for machine discrimination are provided. In addition to the polychromatic luminescent material produced in Example 3, a luminescent material 13 which is an R-based luminescent material that is rapidly excited by a short wave is added as a fourth luminescent material, and excited in the ultraviolet long wave region to the ultraviolet short wave region, respectively. This is an example using four light emitters having different characteristics. In consideration of the machine discrimination, the light emitter 13 has a small influence on the hue change, but the light emission balance is such that the light emission peak can be sufficiently obtained without overlapping the wavelength of the light emission peak with other light emitters.

  A light emitter group constituting this multicolor light emitter is shown in FIG. The luminous body 10, the luminous body 11, and the luminous body 12 are the same luminous bodies as the luminous body 7, the luminous body 8, and the luminous body 9 of Example 3. FIG. 32A, FIG. 32B, FIG. 33A, FIG. 33B, and FIG. 34A show excitation characteristics and light emission characteristics of the light emitter 10, light emitter 11, light emitter 12, and light emitter 13. FIG. ), FIG. 34 (b), FIG. 35 (a), and FIG. 35 (b). The light-emitting body 13 was selected from light-emitting bodies whose excitation wavelength rises at a wavelength longer than 300 nm, considering that the multicolor light-emitting body of Example 3 does not have a large wavelength change at a wavelength shorter than 300 nm. The illuminant 13 is generally classified into a short-wave ultraviolet excitation type, but is an illuminant having an excitation characteristic in which the excitation wavelength rises at a wavelength shorter than 300 nm and remarkably emits light. After selecting the phosphor groups having different excitation characteristics and hues, the pigment content was examined in the same manner as in the other examples.

  Based on the result, the best mixing ratio is shown in FIG. Moreover, the result of the hue evaluation for every ultraviolet irradiation wavelength is shown to Fig.37 (a), (b). FIG. 37A shows a hue evaluation result when a special irradiation apparatus is used as a hue evaluation confirmation means, and FIG. 37B shows a case where a general irradiation apparatus is used as a hue evaluation confirmation means. The hue evaluation results are shown.

  The special irradiation device here uses the irradiation device of the spectrophotometer used in Example 3, and the long wave ultraviolet irradiation lamp (center wavelength) used in Examples 1, 2, and 3 for general irradiation devices as well. 366 nm), medium wave ultraviolet irradiation lamp (center wavelength 302 nm), and short wave ultraviolet irradiation lamp (center wavelength 254 nm). From this result, it was confirmed that the reproduction of the hue including the intermediate color tone from blue to orange occurred in a limited wavelength region from 400 nm to 300 nm and changed from orange to red light emission in the ultraviolet short wave region. .

  FIG. 38 (a) shows the light emission distribution at the time of long wave ultraviolet excitation (center wavelength 365nm), FIG. 38 (b) shows the light emission distribution at the time of long wave ultraviolet wave excitation (center wavelength 340nm), and FIG. The spectral distribution at (center wavelength 302 nm) is shown in FIG. 38 (d), and the spectral distribution at the time of short-wave ultraviolet excitation (center wavelength 254 nm) is shown. 38A, 38B, 38D, and 38D are all relative intensities, and the maximum peak on the waveform is about 80% on the graph. It was. These are measured using a spectrophotometer (850 type spectrofluorometer manufactured by Hitachi, Ltd.), and as a result, it can be confirmed that it has a peak wavelength sufficient for mechanical detection in any wavelength region. In addition to this, it was confirmed that the emission peak of the illuminant 13 different from the multicolor illuminant of Example 3 can be remarkably confirmed during short-wave excitation.

  In this example, the blending ratio of the light emitters 13 is not only set to a light emission intensity that can be easily detected mechanically, but also has an image line configuration for the purpose of confirming a change in hue by visual observation. In the case of handling 13 as special authenticity discrimination information, it is sufficient to lower the blending ratio to suppress the hue change and to reduce the color change to a level that can be detected only by machine discrimination using a spectrophotometer. It goes without saying that it is possible in a range.

  After producing a multicolor illuminant, an ink vehicle was selected to make it into an ink. In the same manner as in Examples 1 to 3, finally, a three-color luminescent ink for gravure printing was prepared with the ink composition shown in FIG. After adding 30 parts by weight of the pigment and adding the multicolor luminescent material to 70 parts by weight of the ink-ink vehicle, 2 parts by weight of a silicon-based antifoaming agent was added as an auxiliary agent, and this was added to a high-speed disperser (special machine). (Industrial Co., Ltd., Homo Disper Homo Disper) was re-stirred at a maximum rotation number of 3000 rpm for 3 minutes to make an ink. Using this gravure lithographic test machine (GP-2 type, manufactured by Kurabo Industries Co., Ltd.), the printed matter intended for gravure printing at 175 lines / inch using non-fluorescent printing coated paper manufactured by the National Printing Bureau Got.

  Since this ink is white under visible light and the white coated paper is the base, it has an image line configuration in which the printing position cannot be specified by visual confirmation. When the hue was confirmed by the same method as the hue confirmation of the illuminant, it was confirmed that the effect of the multicolor illuminant could be exhibited without any loss of the hue.

  As described above, by using the present invention, it is possible to obtain various effects by changing the luminous body group used according to the effects desired by the user, such as visual hue change, machine discrimination, and confidentiality. . In the examples, all of the light emitters are composed of luminescent pigments, but it goes without saying that there is no problem even if they are dyes. In all the examples, a light emitting body having a completely different hue was used because priority was given to the change in hue. However, when priority is given to machine authentication, the shape of the emission spectrum, such as the light emitting body 12 and light emitting body 13 of Example 4, is used. However, it is needless to say that it is technically easy to use a combination of those belonging to the same hue as compared with the four examples of the embodiment, and is within the scope of the present invention.

The emission color, excitation characteristics, and emission wavelength of a general chemical formula are shown. 3 shows selected three types of luminescent pigments in Example 1. (A) shows the excitation characteristic of the light emitter 1, and (b) shows the light emission characteristic of the light emitter 1. (A) shows the excitation characteristic of the light emitter 2, and (b) shows the light emission characteristic of the light emitter 2. (A) shows the excitation characteristic of the light emitter 3, and (b) shows the light emission characteristic of the light emitter 3. The mixing weight of 5 types of samples which changed the mixing weight of 3 types of fluorescent pigments in Example 1 is shown. The hue evaluation of the ultraviolet representative wavelength of five types of samples in Example 1 is shown. The best mixing weight of the three types of fluorescent pigments in Example 1 is shown. The hue evaluation in each ultraviolet wavelength of a multicolor light-emitting body in Example 1 is shown. In Example 1, (a) shows the light emission distribution at the time of exciting the long wave ultraviolet light, (b) shows the light emission distribution at the time of exciting the medium wave ultraviolet light, and (c) shows the light emission distribution at the time of exciting the short wave ultraviolet light. . The positional relationship between a multicolor light emitter and each ultraviolet irradiation lamp in Example 1 is shown. The distance between the multicolor light emitter and the ultraviolet irradiation lamp for reproducing all hues in Example 1 and the evaluation of the respective hues are shown. The compounding ratio of the multicolor luminescent ink composition in Example 1 is shown. 3 shows selected three types of luminescent pigments in Example 2. (A) shows the excitation characteristics of the light emitter 4, and (b) shows the light emission characteristics of the light emitter 4. (A) shows the excitation characteristics of the light emitter 5, and (b) shows the light emission characteristics of the light emitter 5. (A) shows the excitation characteristic of the light emitter 6, and (b) shows the light emission characteristic of the light emitter 6. The best mixing weight of the three types of fluorescent pigments in Example 2 is shown. The hue evaluation in each ultraviolet wavelength of a multicolor light-emitting body in Example 2 is shown. In Example 2, (a) shows the light emission distribution at the time of excitation of the long wave ultraviolet light, (b) shows the light emission distribution at the time of excitation of the medium wave ultraviolet light, and (c) shows the light emission distribution at the time of excitation of the short wave ultraviolet light. . In Example 2, the distance between the multicolor light emitter and the ultraviolet irradiation lamp for reproduction of all hues and the evaluation of each hue are shown. The compounding ratio of the multicolor luminescent ink composition in Example 2 is shown. 3 shows selected three types of luminescent pigments in Example 3. (A) shows the excitation characteristic of the light emitter 7, and (b) shows the light emission characteristic of the light emitter 7. (A) shows the excitation characteristics of the light emitter 8, and (b) shows the light emission characteristics of the light emitter 8. (A) shows the excitation characteristic of the light emitter 9, and (b) shows the light emission characteristic of the light emitter 9. The best mixing weight of the three types of fluorescent pigments in Example 3 is shown. In Example 3, (a) shows a hue evaluation by irradiation of a special irradiation apparatus, and (b) shows a hue evaluation by irradiation of a general irradiation apparatus, with respect to the multicolor light emitter in Example 3. In Example 3, (a) shows the light emission distribution at the time of exciting the long wave ultraviolet light, (b) shows the light emission distribution at the time of exciting the long wave ultraviolet light, and (c) shows the light emission distribution at the time of exciting the short wave ultraviolet light. The compounding ratio of the multicolor luminescent ink composition in Example 3 is shown. 3 shows selected three types of luminescent pigments in Example 4. (A) shows the excitation characteristic of the light emitter 10, and (b) shows the light emission characteristic of the light emitter 10. (A) shows the excitation characteristic of the light emitter 11, and (b) shows the light emission characteristic of the light emitter 11. (A) shows the excitation characteristic of the light emitter 12, and (b) shows the light emission characteristic of the light emitter 12. (A) shows the excitation characteristic of the light emitter 13, and (b) shows the light emission characteristic of the light emitter 13. The best mixing weight of the three types of fluorescent pigments in Example 4 is shown. In Example 4, (a) shows the hue evaluation by irradiation of a special irradiation device, and (b) shows the hue evaluation by irradiation of a general irradiation device, with respect to the multicolor light emitter. (A) is a light emission distribution at the time of excitation of long wave ultraviolet light, (b) is a light emission distribution at the time of excitation of long wave ultraviolet light, and (c) is a light emission distribution at the time of excitation of medium wave ultraviolet light. d) shows the light emission distribution when the shortwave ultraviolet light is excited. The compounding ratio of the multicolor luminescent ink composition in Example 3 is shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Multicolor light-emitting body 2 Long wave ultraviolet irradiation lamp 3 Medium wave ultraviolet irradiation lamp 4 Short wave ultraviolet irradiation lamp

Claims (5)

A multicolor luminescent mixture obtained by mixing at least three luminescent materials having different excitation characteristics by ultraviolet rays,
The light emitters that emit light when irradiated with ultraviolet rays each have a main wavelength of any one of the R region, the G region, and the B region of the RGB display region,
At least one light emitter having a dominant wavelength in the R region is a first light emitting group, at least one light emitter having a dominant wavelength in the G region is a second light emitting group, and at least one having a dominant wavelength in the B region. One luminous body as a third luminous group,
At least three of at least one light emitter selected from the first light emission group, at least one light emitter selected from the second light emission group, and at least one light emitter selected from the third light emission group. A mixture of the above phosphors,
When the light having the first wavelength in the ultraviolet region is irradiated, the emission intensity of at least one of the at least three light emitters mixed is the strongest,
When irradiated with light having a second wavelength different from the first wavelength in the ultraviolet region, at least one of the mixed three or more light emitters has the highest light emission intensity. ,
Of the at least three or more light emitters mixed when irradiated with light having a third wavelength different from the first wavelength and the second wavelength in the ultraviolet region, at least one third light emitter A multicolor luminescent mixture, which is mixed so as to have the highest luminescence intensity.   The multicolor luminescent mixture according to claim 1, wherein the phosphor is selected from at least one phosphor or phosphor.   3. The multicolor luminescent mixture according to claim 1, wherein the illuminant is composed of an illuminant of an inorganic illuminant or a combination of an inorganic illuminant and an organic illuminant. .   A multicolor luminescent ink composition comprising the multicolor luminescent mixture according to claim 1, 2 or 3 mixed with a vehicle.   An image-formed product comprising a printed layer formed using the multicolor luminescent ink composition according to claim 4.

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