JP2012242411A - Hologram sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a novel hologram sheet using a hologram, in which the hologram is reproduced at a wavelength different from that of illumination light to enhance the authenticity of the hologram sheet, unlike a hologram that reproduces a hologram reproduction image at the same wavelength as that of illumination light.SOLUTION: A fluorescent layer is formed on a hologram forming layer. By illuminating the hologram sheet with light that excites the fluorescent material, a hologram reproduction image having a tone of the fluorescent emission in a visible light region can be visually checked, which enhances the counterfeit prevention property of the hologram sheet.

Description

The present invention relates to a novel hologram sheet, and more particularly to a fluorescence emission type hologram sheet in which a fluorescence emitter is arranged at the relief position of a relief hologram that exhibits a phase hologram.
Here, “total reflection” of “totally reflective thin film layer” means that light in the visible light region, that is, light having a wavelength of 400 nm to 800 nm is reflected, and light in the visible light region is reflected. It means not transmitting.
However, it is physically impossible to provide a “layer” that reflects 100% of all light within the wavelength range, and “total reflection” here means, for example, an aluminum metal thin film layer, This means a “layer” that reflects light within that wavelength range with a reflectance of 90% to 100% (the value varies depending on the wavelength of the light to be measured), and thus the transmittance of this layer within that wavelength range. Means a “layer” of less than 10%.
By providing such a “layer”, the hologram sheet of the present invention observes a hologram reproduction image only in the “reflection type”.
In the present specification, “part” indicating the formulation is based on mass. The “hologram” includes a hologram and a hologram having a light diffractive function such as a diffraction grating.

(Main applications)
The main use of the hologram sheet of the present invention is in the art / craft field and commercial field using the hologram itself for decoration, but is not limited to this, and is a hologram sheet used in the counterfeit prevention field. In particular, credit cards and other counterfeited products that can damage cardholders and card companies, driver's licenses, employee ID cards, ID cards such as membership cards, and entrance examinations Votes, passports, banknotes, gift certificates, point cards, stock certificates, securities, lottery tickets, horse betting tickets, bank passbooks, boarding tickets, passports, air tickets, admission tickets for various events, amusement tickets, transportation facilities and public telephones There are prepaid cards.
Each of these is an information recording body that holds information having economic or social value, and it is desirable to have a function that can identify the authenticity of the recording body for the purpose of preventing damage caused by forgery. .

In addition to these information recording media, expensive products such as luxury watches, luxury leather products, precious metal products, jewelry, etc., often referred to as luxury brand products, or storage of such expensive products. Boxes and cases can also be forged. In addition, mass-produced products of famous brands, such as audio products, electrical appliances, etc., or tags that are hung on them are also subject to forgery.
Furthermore, a storage body in which music software, video software, computer software, game software, or the like, which is a copyrighted work, or cases thereof can also be forged. In addition, it is desirable that products such as printer toner, paper, and the like in which supplies to be replaced are limited to genuine materials have a function of identifying their authenticity for the purpose of preventing damage caused by forgery.

(Background technology)
Conventionally, for the purpose of preventing counterfeiting of information recording bodies and various articles described above (collectively referred to as authenticity identification objects), it is said that they have manufacturing difficulties due to the precision of their structures. In many cases, holograms are applied as authenticity distinguishable. However, since the hologram manufacturing method itself is known and can be precisely processed by that method, when the hologram is merely for visual judgment, there is no difference between a genuine hologram and a forged hologram. It is difficult to distinguish.
These authentic identification objects, in particular, articles that have been subjected to hologram images in a label form or transfer form, are not only used for authentic identification of visual confirmation of hologram images, but also by using a new authenticity identification method. There is a need to identify the authenticity of.

(Prior art)
In order to meet these requirements, there has been proposed a hologram sheet having a light selective reflection layer that is laminated on a hologram and reflects only one of the left-handed polarized light and the right-handed polarized light among the incident light. (For example, refer to Patent Document 1.)
As this light selective reflection layer, cholesteric liquid crystal is used, and the anti-counterfeiting property is enhanced by a method of confirming using a polarizing plate or the like.
However, as described in Patent Document 1, since the reflectance of the reflective thin film layer on the hologram forming layer is high, the light that is transmitted without being reflected by the cholesteric liquid crystal layer (complementary light of selective reflected light) Reflecting on the reflective thin film layer and returning to the cholesteric liquid crystal layer again (hereinafter referred to as return light), this return light becomes a noise component when observing the cholesteric liquid crystal and is added to and mixed with the selectively reflected light. However, the color tone was not the original color of the liquid crystal, and it was even difficult to see and identify.

In addition, the cholesteric liquid crystal material itself is expensive, and in order to draw out the liquid crystal performance, it is indispensable to form an alignment film in contact with the liquid crystal layer. There have been problems such as blurring and distortion of the image when light for reproducing the image passes through the liquid crystal layer.
For this reason, it has been devised to suppress the light scattering property of the cholesteric liquid crystal layer or to make the cholesteric liquid crystal layer itself thin. However, in order to suppress the light scattering property of the cholesteric liquid crystal layer, the refractive index difference is reduced, When the liquid crystal layer is made thin, the function as the light selective reflection layer described above is deteriorated, and it has a drawback that it is difficult to obtain optimum conditions for ensuring the clarity and anti-counterfeit performance of the hologram image. .

JP 2007-90538 A

  Accordingly, the present invention has been made to solve such problems. The purpose is to provide a phase hologram hologram forming layer, that is, a transparent resin having a hologram relief so that a fluorescent layer is in contact with the hologram relief, and a total reflection thin film layer is further provided thereon, under natural light. The hologram reconstructed image can be visually recognized by the reflected light from the total reflective thin film layer, and at first glance, it can be observed like a normal hologram sheet, but it is different from the wavelength by illumination of a light source having a predetermined wavelength. It is to provide a novel hologram sheet that allows a hologram reproduction image having only a single wavelength to appear in a specific direction. Furthermore, since such a hologram sheet has not existed so far, it is to provide a novel decorative property and an anti-counterfeit property to which this is applied.

To solve the above problem,
The first aspect of the hologram sheet of the present invention is:
A transparent resin layer having a hologram relief including a diffraction grating group corresponding to a hologram image, a fluorescent layer provided in contact with the hologram relief, and a total reflection thin film layer in this order on one surface of the transparent substrate. It is characterized by being provided with.
According to the hologram sheet of the first aspect,
A transparent resin layer having a hologram relief including a diffraction grating group corresponding to a hologram image, a fluorescent layer provided in contact with the hologram relief, and a total reflection thin film layer in this order on one surface of the transparent substrate. It is possible to provide a hologram sheet characterized in that the hologram sheet is provided with a high design property and a high level of forgery prevention.
The second aspect of the hologram sheet of the present invention is:
The fluorescent layer is formed with a uniform thickness following the unevenness forming the hologram relief.
According to the hologram sheet of the second aspect,
It is possible to provide the hologram sheet according to the first aspect, wherein the fluorescent layer is formed with a uniform thickness following the unevenness forming the hologram relief. Can be provided.
The third aspect of the hologram sheet of the present invention is:
The fluorescent layer has a thickness of 0.01 μm or more and 0.1 μm or less.

According to the hologram sheet of the third aspect,
The hologram sheet according to the second aspect, wherein the fluorescent layer has a thickness of 0.01 μm or more and 0.1 μm or less, and can reproduce a hologram reproduction image with extremely high definition. A hologram sheet can be provided.
The fourth aspect of the hologram sheet of the present invention is:
The hologram relief of the transparent resin layer is
A transparent layer having a uniform thickness is formed on the transparent substrate, and a fluorescent layer having a uniform thickness is formed on the transparent layer, and then the transparent layer and the fluorescent layer are simultaneously deformed. It is characterized by being provided.
According to the hologram sheet of the fourth aspect,
The hologram relief of the transparent resin layer is
A transparent layer having a uniform thickness is formed on the transparent substrate, and a fluorescent layer having a uniform thickness is formed on the transparent layer, and then the transparent layer and the fluorescent layer are simultaneously deformed. It is possible to provide a hologram sheet according to any one of the second and third aspects characterized in that the hologram reproduction sheet is provided, and to provide a hologram sheet with a clearer hologram reproduction image under natural light. it can.
A diffraction grating group for reproducing a hologram image is formed as a hologram relief as a substantially flat surface on the surface of the transparent resin layer. On the hologram relief, the fluorescent layer has a uniform thickness following the hologram relief. Is provided.
In other words, the hologram relief shows the phase difference as a phase hologram in a “relief shape”, but the fluorescent layer is provided by following (along) the “relief shape” having this phase difference. Fluorescence emitted from the light will be emitted with (including) the phase difference.

Then, following the “relief shape” of the fluorescent layer having the relief shape, a total reflection thin film layer is further provided on the fluorescent layer.
Therefore, the total reflection thin film layer also has a “relief shape”, and this fluorescent layer is not visually recognized under natural light, and the hologram reproduction image is observed by the “relief shape” on the reflection surface of the total reflection thin film layer. It will be.
However, when an illumination light source that emits light from the fluorescent layer, that is, illumination of a light source having a predetermined “predetermined wavelength” is used, a hologram reproduction image by “only a specific wavelength” that is different from the “predetermined wavelength” is obtained. Appearing in a specific direction, the observer again observes the hologram reproduction image with this “specific wavelength”.
The principle of hologram reproduction by this fluorescent layer will be described below.
That is, in contrast to the Huygens secondary wave generated when the relief hologram is reproduced, in the case of the hologram sheet of the present invention, the secondary wave corresponds to the phosphor (or fluorescent light) arranged on the hologram relief surface. This light emission plays a role and includes the phase difference of the hologram relief including the diffraction grating group corresponding to the hologram image. Is emitted to the observer side.
This emitted light (hereinafter also referred to as emitted light) causes an interference phenomenon in the space on the hologram relief surface, and as a result, a predetermined hologram reproduction image is developed in a predetermined direction.
A phosphor is a substance that absorbs energy such as ultraviolet rays, electron beams, and X-rays and emits it as visible light. For example, a material obtained by adding a trace amount of metal ions responsible for light emission such as Eu and Ce to a base ceramic crystal. Etc. In this case, metal ions contribute to light emission and are excited by absorbing energy applied from outside (energy such as ultraviolet rays, electron beams, X-rays, and of course visible rays, infrared rays, etc.), and then the base. Lights when returning to the state. The lattice of the host crystal functions to chemically stabilize the ions by surrounding the metal ions, and to control the emission color and intensity by adjusting the crystal field and coordination environment.
The present invention uses a phosphor material that emits light in the visible light region by Stokes shift among these fluorescent emissions. Of course, a material that emits light in the visible light region due to infrared excitation can also be used.

The present invention reproduces a hologram with a wavelength different from the wavelength of the illumination light source of the hologram. For example, it can be illuminated with ultraviolet rays and a green hologram can be visually recognized. Among them, only the hologram shines in a place without a normally used green illumination light source (for example, an argon laser), appears to float in the air, and is excellent in design.
In addition, in a single-wavelength light source reproduction type, under the illumination light from a multi-wavelength light source such as a fluorescent lamp, a hologram reproduction image at each wavelength is doubled (reproduction angle is slightly shifted and reproduced. Image) ”), and when a hologram of a type in which the hologram reproduction image cannot be visually recognized is recorded as a relief hologram, the light emitted from the fluorescent layer is“ single wavelength ”. It is also possible to include a “hologram that can be observed only when it emits light”, and it is possible to enhance its design and anti-counterfeiting properties.
In a normal hologram, due to its reproduction principle, the direction in which the hologram reproduction image appears depends on the direction of illuminating the hologram, and when the illumination for hologram reproduction is moved obliquely upward from directly above In the hologram sheet of the present invention, the hologram reproduction image that is reflected and reproduced by the total reflection thin film layer behaves in the same manner. However, the hologram reproduction image reproduced by the light emission of the fluorescent layer shows that the illumination of the light source having the predetermined “predetermined wavelength” is applied only in the same specific direction. Since it has a unique property of “appearing”, its anti-counterfeiting property can be further enhanced.
Of course, because the wavelength range of the light source capable of reproducing the hologram is very narrow, only those who know the specific wavelength range can reproduce the hologram, which is useful for authenticity determination. . Also, only those who can know the value of the Stokes shift described above can predict the color tone of the hologram reproduction image, and only the hologram that can pass through the bandpass filter by looking through the bandpass filter adjusted to the reproduction wavelength is authentic. It can also be determined.
Further, the angle (diffraction angle) passing through the bandpass filter also depends on the amount of Stokes shift, and only those who can know the value can make a determination at the specific angle.
Furthermore, by including a plurality of phosphors, this reproduced image appears in different colors at a plurality of angles, which is superior both in terms of design and authenticity.
As shown in the Jablonsky diagram shown in FIG. 1, the principle of fluorescence emission is first determined by light absorption from the ground state (S0: singlet state) of the phosphor (including fluorescent dye, fluorescent pigment, fluorescent dye, etc.). The luminescent material excited in any one of the vibration states (S1), second (S2), third excited state (S3),... Or the triplet state (T1, T2) by intersystem crossing. The phosphor in the lowest vibration state of S1 returns to the ground state due to a non-radiation process or emits fluorescence. The molecule in the triplet state returns to the ground state by a non-radiative process or phosphorescence.

Since the transition between singlets occurs instantaneously, the half-life of fluorescence is as short as 10 ⁻⁴ sec or less. The time required for the transition is said to be excited at 10 ⁻¹⁵ sec and then to emit fluorescence at 10 ⁻⁹ to 10 ⁻⁷ sec.
On the other hand, the transition from triplet to singlet is forbidden due to the prohibition of spin change, and spontaneous emission is difficult to occur.
Whether or not light is emitted when returning to the ground state, whether the intensity of light is strong or weak, and whether the fluorescence lifetime is long or short largely depends on the molecular structure of the phosphor material and the environment in which the molecule is placed.
The wavelength distribution of the emitted light of the phosphor material is called a fluorescence spectrum, and the fluorescence spectrum is created by plotting the fluorescence intensity relative to the fluorescence wavelength. (In actual fluorescence spectrum measurement, excitation light with a constant wavelength and intensity is used as the light source, and when dealing with phosphors, the emission spectrum is called the fluorescence spectrum.) The wavelength (energy) shown in the fluorescence spectrum ) Is equal to the energy difference from the lowest vibration energy level in the primary excited state to the preferential vibration energy level in the ground state.
If the amplitude of the fluorescence is similar to the amplitude structure of the excited state and the ground state, the wavelength of the light energy absorbed by the fluorescent dye and the wavelength emitted as fluorescence are theoretically related to the amplitude of the excitation on the longest wavelength side. Will be the same. However, in practice, the fluorescence spectrum of most fluorescent dyes shifts to the longer wavelength (low energy) side. The difference between the peak wavelengths of the excitation spectrum and the fluorescence spectrum is called the Stokes shift, and this wavelength difference is caused by the energy released in the excited state before the emission of fluorescence being converted into thermal energy.
The Stokes shift is very important in the sensitivity of fluorescence, and when detecting fluorescence, the background can be lowered because it is not affected by excitation light.
When the wavelength and intensity of incident light are constant (for example, when controlled laser light is used as a light source), the emitted fluorescence is directly proportional to the amount of fluorescent material. Therefore, in order to make the fluorescence intensity constant, it is necessary to make the amount of the phosphor in the fluorescent layer formed on the hologram relief surface constant.

Of course, when the concentration of the phosphor is high, saturation occurs and the linearity is lost, resulting in a constant intensity, or the distance between the phosphors is very close, and only the vicinity of the surface is excited and the emitted fluorescence is absorbed. Therefore, in order to sufficiently obtain the coherence of fluorescent light, which is the object of the present invention, it exists uniformly only in the vicinity of the hologram relief surface, rather than a large amount of phosphors dispersed in the thickness direction of the fluorescent layer. In order to produce a higher interference phenomenon, it is desirable that the particle size is 1 to 10 times, more preferably 1 to 3 times the particle size of the phosphor. When the phosphor is a dye and is dissolved in the resin forming the fluorescent layer, it is necessary to keep the resin layer thin. When dyeing with a fluorescent dye, the above-mentioned object can be achieved by dyeing only the relief surface of the transparent resin layer itself forming the hologram relief.
Also, depending on the phosphor, the emitted fluorescence intensity (brightness) varies, and the fluorescence intensity directly affects the sensitivity, so the fluorescence intensity of the phosphor is a very important factor. The fluorescence intensity depends on the following two characteristics of the phosphor:
・ Light absorption efficiency (absorption coefficient)
-Conversion efficiency between excitation light and fluorescence (quantum yield)
Since the fluorescence intensity is proportional to the extinction coefficient (ε) and quantum yield (φ) of the phosphor, it is expressed by the following equation.
・ Fluorescence intensity (luminance) 吸 光 Absorption coefficient (ε) × quantum yield (φ)
Here, the extinction coefficient of the phosphor means the amount of light of a specific wavelength absorbed by the phosphor, and the molar extinction coefficient is defined as the optical density of a 1M (1 mol) fluorescent dye solution per 1 cm of the optical path. Useful phosphors have a molar extinction coefficient of 10,000 or more. The conversion efficiency (quantum yield) between excitation light and fluorescence can be obtained from the following equation.
Φ = number of emitted photons / number of absorbed photons Here, the quantum yield (φ) ranges from “0” (non-fluorescent substance) to “1” (efficiency 100%). Examples showing the quantum yield of the phosphor include fluorescein (φ = 0.9) and Cy5 (φ = 0.3). The peak wavelength of the absorption spectrum is used for the usual quantum yield (φ) measurement.

Fluorescein (ε = 70,000, φ = 0.9) and Cy5 (ε = 200,000, φ = 0.3) have extremely high luminance, and these phosphors have quantum yields and extinction coefficients. Although very different, the fluorescence intensity is equivalent.
Therefore, when evaluating the phosphor, it is necessary to consider both the extinction coefficient and the quantum yield. Fluorescence intensity is also affected by the intensity of incident light. Theoretically, when the amount of incident light is increased, the number of excited phosphors increases, and the amount of emitted light (the number of photons or the ground state falls to the ground state) Number) increases and is observed as an increase in fluorescence intensity. However, in reality, if the incident light intensity is increased too much, all the phosphors are always excited, causing fluorescence destruction, resulting in attenuation or disappearance of the fluorescence intensity and loss of correlation with the fluorescence intensity. Therefore, it is necessary to appropriately determine the amount of incident light.
In addition, the quantum yield, excitation spectrum, and fluorescence spectrum of the phosphor are determined based on environmental conditions, that is, environmental temperature, ion concentration, pH, excitation light intensity, covalent bond with resin, non-covalent interaction (intercalation The optical filter (low-pass filter, high-pass filter, band-pass filter, etc.) that makes it easy to recognize the excitation light wavelength and fluorescent light in consideration of these environmental conditions. May need to be set as needed.

Another environmental effect is photobleaching with light. Since the phosphor in the excited state is chemically activated as compared with the ground state, it is more likely to be destroyed and, for example, the “excited fluorescent dye molecule” proceeds with a chemical reaction, but is less frequent. May have a low fluorescence structure. The progress of this chemical reaction depends on the sensitivity of individual phosphors to photobleaching and the chemical environment, the intensity of excitation light, the irradiation time of excitation light, the number of repetitions of optical scans for observation and authentication, etc. Settings according to the purpose are required.
When the wavelength and intensity of incident light are made constant, such as when a controllable laser beam is used as the light source, the emitted fluorescence (number of photons) is directly proportional to the amount of phosphor. If the phosphor is at a very high concentration, the signal response is non-linear.
The number of photons emitted from a certain amount of phosphor can be amplified by repeating the excitation / emission cycle. When the excitation light intensity and the phosphor concentration are constant, the total amount of emitted light is proportional to the irradiation time (period in which excitation light is irradiated to a fluorescent dye or the like). If the irradiation time is longer than the time of the excitation / emission cycle, the phosphor repeats the excitation / emission cycle many times. The fluorescence intensity (number of emitted photons) can be measured by any light receiving element.
When measuring low-intensity light, a photomultiplier tube (PMT) having an amplification mechanism is effective. When light having sufficient energy enters the PMT, electrons are emitted from the cathode, and the electrons are amplified as a current. The currents of these light receiving elements are proportional to the intensity of incident light, and the fluorescence intensity is usually displayed in arbitrary units (eg, rfu: relative-fluorescence units).

The phosphor is generally manufactured by a solid phase reaction method in which a phosphor material is fired. In this solid phase reaction method, since the raw material mixture is fired at a high temperature, the obtained fired cake is often a product in which phosphor particles are hard and aggregated. Therefore, normally, when producing the phosphor, for example, a pulverization step using a ball mill, a mortar, etc., is performed, but as a method for suppressing damage to the surface of the phosphor particles at this time, using a fluid reactor device, Substantially monodispersed phosphor-precursor particles are suspended in a flowing gas and baked to produce substantially monodispersed fluorescent particles that are not aggregated. According to this method, fluorescent particles having a size of less than 1 μm can be produced.
In addition, for example, when manufacturing a ZnGa ₂ O ₄ : Mn phosphor, the phosphor raw material before firing is prepared by a wet precipitation method, which enables firing at a low temperature and suppresses aggregation of phosphor particles. can do.
Further, for example, regarding a method for producing a phosphor having an alkaline earth aluminate-based or alkaline earth silicate-based host crystal, strontium nitrate is used as a phosphor raw material containing Sr, and a raw material mixture or suspension There is a method of forming droplets so as to have a desired particle diameter and firing the droplets. As a result, a phosphor having extremely brittle properties can be obtained and can be easily pulverized to a minute size.
As the phosphor material, a compound containing an element constituting the phosphor to be manufactured (hereinafter also referred to as “phosphor constituent element”) can be used. Examples thereof include oxides, hydroxides, carbonates, nitrates, sulfates, oxalates, carboxylates, halides, nitrides and the like containing phosphor constituent elements. When selecting the phosphor raw material, it is preferable to select in consideration of the reactivity to the obtained phosphor. Furthermore, corresponding to each phosphor constituting element constituting the phosphor, one kind of phosphor raw material may be used, or two or more kinds may be used in combination in any combination and ratio.
Further, the impurities contained in each phosphor raw material of the phosphor are not particularly limited as long as the phosphor characteristics are not adversely affected.
The weight median diameter of each phosphor material is usually 0.01 μm or more and 0.5 μm or less. For this reason, depending on the type of the phosphor material, pulverization may be performed in advance by a dry pulverizer such as a jet mill. As a result, each phosphor raw material can be uniformly dispersed in the raw material mixture, and the solid phase reactivity of the raw material mixture can be increased by increasing the surface area of the phosphor raw material, thereby suppressing the generation of impurity phases. It becomes.

For example, specific examples of phosphor materials containing Ba include BaO, Ba (OH) ₂ .8H ₂ O, BaCO ₃ , Ba (NO ₃ ) ₂ , BaSO ₄ , Ba (C ₂ O ₄ ) · ₂ H _2. O, Ba (OCOCH ₃ ) ₂ , BaCl _{2 and the} like.
Specific examples of phosphor raw materials containing Ca include CaO, Ca (OH) ₂ , CaCO ₃ , Ca (NO ₃ ) ₂ .4H ₂ O, CaSO ₄ .2H ₂ O, Ca (C ₂ O ₄ ) · H. ₂ O, Ca (OCOCH ₃ ) ₂ .H ₂ O, anhydrous CaCl ₂ (however, it may be a hydrate).
Specific examples of the phosphor raw material containing Sr include SrO, Sr (OH) ₂ .8H ₂ O, SrCO ₃ , Sr (NO ₃ ) ₂ , SrSO ₄ , Sr (C ₂ O ₄ ) · H ₂ O, Sr. (OCOCH ₃ ) ₂ · 0.5H ₂ O, SrCl _{2 and the} like.
Specific examples of the phosphor material containing Zn include ZnO, Zn (C ₂ O ₄ ) · 2H ₂ O, ZnSO ₄ · 7H ₂ O, and the like.
Specific examples of the phosphor raw material containing Mg include MgCO ₃ , MgO, MgSO ₄ , Mg (C ₂ O ₄ ) · 2H ₂ O, and the like.
Specific examples of the phosphor raw material containing Si include SiO ₂ , H ₄ SiO ₄ , Si (OCOCH ₃ ) _{4 and the} like.
Specific examples of the phosphor material containing Eu include Eu ₂ O ₃ , Eu ₂ (SO ₄ ) ₃ , Eu ₂ (C ₂ O ₄ ) ₃ , EuCl ₂ , EuCl ₃ , Eu (NO ₃ ) ₃ .6H _2. O etc. are mentioned.
Specific examples of each phosphor raw material containing Sm, Tm, and Yb include compounds in which Eu is replaced with Sm, Tm, and Yb, respectively, in the compounds listed as specific examples of the Eu source.

Specific examples of the phosphor raw material containing Mn include MnO, MnO ₂ , Mn ₂ O ₃ , MnF ₂ , MnCl ₂ , MnBr ₂ , Mn (NO ₃ ) ₂ .6H ₂ O, MnCO ₃ , MnCr ₂ O _{4 and the} like. Is mentioned.
Specific examples of the phosphor material containing Cr include Cr ₂ O ₃ , CrF ₃ (may be a hydrate), CrCl ₃ , CrBr ₃ .6H ₂ O, Cr (NO ₃ ) ₂ .9H ₂ O. , (NH ₄ ) ₂ CrO _{4 and the} like.
Specific examples of the phosphor raw material containing Tb include Tb ₄ O ₇ , TbCl ₃ (including hydrate), TbF ₃ , Tb (NO ₃ ) ₃ .nH ₂ O, Tb ₂ (SiO ₄ ) ₃ , Examples thereof include Tb ₂ (C ₂ O ₄ ) ₃ · 10H ₂ O. Further, other phosphor materials (for example, Eu source) and Tb source may be co-precipitated before use.
Examples of phosphor materials containing _{Pr, Pr 2 O 3, PrCl} 3, PrF 3, Pr (NO 3) 3 · 6 H 2 O, Pr 2 (SiO 4) 3, Pr 2 (C 2 O 4 ) ₃ · 10H ₂ O and the like.
Specific examples of the phosphor raw material containing Ce include CeO ₂ , CeCl ₃ , Ce ₂ (CO ₃ ) ₃ .5H ₂ O, CeF ₃ , Ce (NO ₃ ) ₃ .6H ₂ O, and the like.
Specific examples of the phosphor material containing Lu include Lu ₂ O ₃ , LuCl ₃ , LuF ₃ (may be a hydrate), Lu (NO ₃ ) ₃ (may be a hydrate), etc. Is mentioned.
Specific examples of phosphor raw materials containing La include La ₂ O ₃ , LaCl ₃ · ₇ H ₂ O, La ₂ (CO ₃ ) ₃ · H ₂ O, LaF ₃ , La (NO ₃ ) ₃ · 6H ₂ O. , La ₂ (SO ₄ ) _{3 and the} like.
Specific examples of the phosphor material containing Gd include Gd ₂ O ₃ , GdCl ₃ .6H ₂ O, Gd (NO ₃ ) ₃ .5H ₂ O, Gd ₂ (SO ₄ ) ₃ / 8H ₂ O, GdF _{3 and the} like. Is mentioned.

Specific examples of the phosphor material containing Ge include GeO ₂ , Ge (OH) ₄ , Ge (OCOCH ₃ ) ₄ , GeCl _{4 and the} like.
Specific examples of the phosphor material containing Ga include Ga ₂ O ₃ , Ga (OH) ₃ , Ga (NO ₃ ) ₃ .nH ₂ O, Ga ₂ (SO ₄ ) ₃ , and GaCl ₃ .
Specific examples of the phosphor material containing Al include Al ₂ O ₃ such as α-Al ₂ O ₃ and γ-Al ₂ O ₃ , Al (OH) ₃ , AlOOH, Al (NO ₃ ) ₃ · 9H ₂ O, Examples include Al ₂ (SO ₄ ) ₃ and AlCl ₃ .
Specific examples of the phosphor raw material containing P include P ₂ O ₅ , Ba ₃ (PO ₄ ) ₂ , Sr ₃ (PO ₄ ) ₂ , (NH ₄ ) ₃ PO _{4 and the} like.
Specific examples of the phosphor raw material containing B include B ₂ O ₃ and H ₃ BO ₃ .
In addition, you may use the raw material illustrated above, after coprecipitating as needed.
Further, phosphor raw materials corresponding to N element, O element, halogen element, etc. are usually manufactured as phosphors as anion components of the phosphor raw materials of the respective phosphor constituting elements or as components contained in the firing atmosphere. Sometimes supplied.
After preparing a raw material mixture by mixing phosphor raw materials, the raw material mixture is fired at a predetermined temperature and atmosphere. At this time, it is preferable to perform the mixing sufficiently.
Although it does not specifically limit as said mixing method, Specifically, the method quoted as the following (A) and (B) can be used. As for these various conditions, for example, it is possible to select conditions such as mixing and using two kinds of balls having different particle diameters in a ball mill.

(A) Dry pulverizer such as hammer mill, roll mill, ball mill, jet mill, etc., or pulverization using mortar and pestle, and mixer such as ribbon blender, V-type blender, Henschel mixer, or mortar and pestle And a dry mixing method in which the above phosphor raw materials are pulverized and mixed.
(B) Add a solvent or dispersion medium such as an alcohol solvent such as methanol or ethanol or water to the phosphor raw material, and mix using, for example, a pulverizer, a mortar and pestle, or an evaporating dish and a stirring bar, A wet mixing method in which a solution or slurry is made and then dried by spray drying, heat drying, or natural drying.
The mixing of the phosphor raw material can be either wet or dry depending on the physical properties of the phosphor raw material.
In addition, when using a material that easily oxidizes and absorbs moisture, such as halide and nitride, for example, an inert gas such as argon gas or nitrogen gas is filled and mixed in a glove box in which moisture is controlled.
In addition, the phosphor material may be sieved for the purpose of, for example, uniforming the particle size during mixing and pulverization. In this case, various types of commercially available sieves can be used, but it is preferable to use a resin mesh such as a nylon mesh rather than a metal mesh in terms of preventing impurities from being mixed.
In the firing step, a fired product is obtained by firing the obtained raw material mixture. The obtained fired product usually has the composition of the intended phosphor, but the particles are sintered into a fired cake.

Furthermore, when the number of heat-resistant containers in the baking furnace is large in baking, for example, the rate of heat transfer to each heat-resistant container can be made uniform, for example, by slowing the temperature increase rate. It is preferable for firing without any problems.
The firing conditions such as the firing temperature, pressure, and atmosphere in the firing step are preferably set appropriately for each phosphor to be manufactured.
Furthermore, in order to further improve the weather resistance such as moisture resistance or to improve the dispersibility of the phosphor in the phosphor-containing part of the light emitting device, the surface of the phosphor is coated with a different substance as necessary. You may perform surface treatments, such as.
Examples of substances that can be present on the surface of the phosphor (hereinafter also referred to as “surface treatment substances”) include organic compounds, inorganic compounds, glass materials, and the like. Examples of the organic compound include acrylic resins, heat-meltable polymers such as polycarbonate, polyamide, and polyethylene, latex, polyorganosiloxane, and the like.
Examples of inorganic compounds include magnesium oxide, aluminum oxide, silicon oxide, titanium oxide, zirconium oxide, tin oxide, germanium oxide, tantalum oxide, niobium oxide, vanadium oxide, boron oxide, antimony oxide, zinc oxide, yttrium oxide, oxide Examples thereof include metal oxides such as lanthanum and bismuth oxide, metal nitrides such as silicon nitride and aluminum nitride, orthophosphates such as calcium phosphate, barium phosphate, and strontium phosphate, and polyphosphates. And at least one selected from the group consisting of lithium phosphate, sodium phosphate, and potassium phosphate, and at least one selected from the group consisting of barium nitrate, calcium nitrate, strontium nitrate, barium hydrochloride, calcium hydrochloride, and strontium hydrochloride. Can also be used in combination. Among them, it is preferable to use a combination of sodium phosphate and calcium nitrate. Further, when barium, calcium, or strontium is present on the phosphor surface, the surface treatment can be performed using only a phosphate such as sodium phosphate.

Examples of the glass material include borosilicate, phosphosilicate, and alkali silicate. Any one of these surface treatment substances may be used alone, or two or more thereof may be used in any combination and ratio.
The phosphor subjected to the surface treatment has these surface treatment substances. Examples of the presence of the surface treatment substance include the following.
(I) A mode in which the surface treatment substance constitutes a continuous film and covers the surface of the phosphor.
(Ii) An embodiment in which the surface of the phosphor is coated by the surface treatment substance becoming a large number of fine particles and adhering to the phosphor surface.
The adhesion amount or the coating amount of the surface treatment substance on the surface of the phosphor is 0.1% by weight or more, 30% by weight or less, preferably 15% by weight or less based on the weight of the phosphor. desirable. If the amount of the surface treatment substance relative to the phosphor is too large, the light emission characteristics of the phosphor may be impaired. If the amount is too small, the surface coating will be incomplete, and the moisture resistance and dispersibility will not be improved. There is.
The surface treatment method is not particularly limited. For example, a metal oxide (described below)
And a coating treatment method using silicon oxide).
The phosphor is mixed in an alcohol such as ethanol and stirred, and further an alkaline aqueous solution such as ammonia water is mixed and stirred. Next, a hydrolyzable alkyl silicate such as tetraethylorthosilicate is mixed and stirred. After the resulting solution is allowed to stand for 30 minutes, the supernatant containing silicon oxide particles that have not adhered to the phosphor surface is removed. Next, alcohol mixing, stirring, standing, and removal of the supernatant are repeated several times, and then a vacuum treatment is performed at 150 ° C. for 2 hours to obtain a surface-treated phosphor.
In addition to the surface treatment method of the phosphor, for example, a method of attaching spherical silicon oxide fine powder to the phosphor, a method of attaching a silicon compound film to the phosphor, and coating the surface of the phosphor fine particles with polymer fine particles Methods, a method of coating the phosphor with an organic material, an inorganic material, a glass material, etc., a method of coating the surface of the phosphor by a chemical vapor reaction method, a method of attaching metal compound particles, and the like can be used.
As examples of the crystal structure of the phosphor, orthosilicate crystal structures such as (Ba, Sr, Ca, Mg) ₂ SiO ₄ : Eu, Ca ₃ (Sc, Mg, Na, Li) ₂ Si ₃ O ₁₂ : Garnet-based crystal structure such as Ce, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Epatite-based crystal structure such as Eu, M ₃ Si ₆ O ₁₂ N ₂ : Eu (where M is an alkali A nitride-based crystal structure such as an earth metal element). Among these, an orthosilicate crystal structure or a garnet crystal structure is preferable.

(Green phosphor)
The emission peak wavelength of the green phosphor is usually 500 nm or more, preferably 510 nm or more, more preferably 515 nm or more, and usually 550 nm or less, especially 542 nm or less, and more preferably 535 nm or less. If this emission peak wavelength λp is too short, it tends to be bluish, while if it is too long, it tends to be yellowish, and there is a possibility that the characteristics as green light will deteriorate.
In addition, the half-value width of the emission peak of the green phosphor is usually 10 nm or more and usually 130 nm or less, and is preferably adjusted as appropriate according to the application. If the full width at half maximum FWHM is too narrow, the emission intensity may decrease, and if it is too wide, the color purity may decrease.
The green phosphor has an external quantum efficiency of usually 60% or more, preferably 70% or more, and a median diameter D50 is usually about 1 μm.
As a specific example of the green phosphor, a europium activated alkali represented by (Mg, Ca, Sr, Ba) Si ₂ O ₂ N ₂ : Eu that is composed of fractured particles having a fractured surface and emits light in the green region. Examples include earth silicon oxynitride phosphors.

Other green phosphors include Eu-activated aluminate phosphors such as Sr ₄ Al ₁₄ O ₂₅ : Eu, (Ba, Sr, Ca) Al ₂ O ₄ : Eu, and (Sr, Ba) Al _{2. Si 2 O 8: Eu, (} Ba, Mg) 2 SiO 4: Eu, (Ba, Sr, Ca, Mg) 2 SiO 4: Eu, (Ba, Sr, Ca) 2 (Mg, Zn) Si 2 O 7 : Eu, (Ba, Ca, Sr, Mg) ₉ (Sc, Y, Lu, Gd) ₂ (Si, Ge) ₆ O ₂₄ : Eu-activated silicate phosphor such as Eu, Y ₂ SiO ₅ : Ce, Ce, Tb activated silicate phosphor such as Tb, Sr ₂ P ₂ O ₇ —Sr ₂ B ₂ O ₅ : Eu activated borate phosphate phosphor such as Eu, Sr ₂ Si ₃ O ₈ -2SrCl ₂ : Eu-activated halo silicate phosphor such as Eu, Zn ₂ SiO _4: Mn-activated silicate phosphors such as _{Mn, CeMgAl 11 O 19: Tb} , ₃ Al ₅ O _12: Tb-activated aluminate phosphors such as _{Tb, Ca 2 Y 8 (SiO} 4) 6 O 2: Tb, La 3 Ga 5 SiO 14: Tb -activated silicate phosphors such as Tb, (Sr, Ba, Ca) Ga ₂ S ₄ : Eu, Tb, Sm activated thiogallate phosphors such as Eu, Tb, Sm, Y ₃ (Al, Ga) ₅ O ₁₂ : Ce, (Y, Ga, Tb, La, Sm, Pr, Lu) ₃ (Al, Ga) ₅ O ₁₂ : Ce-activated aluminate phosphor such as Ce, Ca ₃ Sc ₂ Si ₃ O ₁₂ : Ce, Ca ₃ (Sc, Mg, Na, Li) ₂ Si ₃ O ₁₂ : Ce activated silicate phosphor such as Ce, Ce activated oxide phosphor such as CaSc ₂ O ₄ : Ce, Eu activated oxynitride phosphor such as Eu activated β sialon _{, BaMgAl 10 O 17: Eu,} Eu such as Mn, Mn-activated aluminate phosphor, SrAl ₂ O _4: Eu such as Eu Activated aluminate phosphors, (La, Gd, Y) 2 O 2 S: Tb Tsukekatsusan sulfide phosphor such as Tb, LaPO _4: Ce, Ce and Tb such, Tb-activated phosphate phosphor, Sulfide phosphors such as ZnS: Cu, Al, ZnS: Cu, Au, Al, (Y, Ga, Lu, Sc, La) BO ₃ : Ce, Tb, Na ₂ Gd ₂ B ₂ O ₇ : Ce, Tb (Ba, Sr) ₂ (Ca, Mg, Zn) B ₂ O ₆ : Ce, Tb activated borate phosphors such as K, Ce, Tb, Ca ₈ Mg (SiO ₄ ) ₄ Cl ₂ : Eu, Mn Eu, Mn activated halosilicate phosphors such as (Sr, Ca, Ba) (Al, Ga, In) ₂ S ₄ : Eu activated thioaluminate phosphors and thiogallate phosphors such as Eu, (Ca, Sr) ₈ (Mg, Zn) (SiO ₄ ) ₄ Cl ₂ : Eu, Mn activated halosilicate phosphor such as Eu, Mn, M ₃ S i ₆ O ₉ N ₄ : Eu, M ₃ Si ₆ O ₁₂ N ₂ : Eu (where M represents an alkaline earth metal element). It is also possible to use Eu-activated oxynitride phosphors such as

In addition, as the green phosphor, it is also possible to use a pyridine-phthalimide condensed derivative, a benzoxazinone-based, a quinazolinone-based, a coumarin-based, a quinophthalone-based, a naltalimide-based fluorescent pigment, or an organic phosphor such as a terbium complex. is there.
Any one of the green phosphors exemplified above may be used, or two or more may be used in any combination and ratio.
(Orange to red phosphor)
The emission peak wavelength of the orange to red phosphor is usually in the wavelength range of 570 nm or more, preferably 580 nm or more, more preferably 585 nm or more, and usually 780 nm or less, preferably 700 nm or less, more preferably 680 nm or less. Is preferred.
Examples of such orange to red phosphors include europium represented by (Mg, Ca, Sr, Ba) ₂ Si ₅ N ₈ : Eu that is composed of fractured particles having a red fracture surface and emits light in the red region. The activated alkaline earth silicon nitride phosphor is composed of growing particles having a substantially spherical shape as a regular crystal growth shape, and emits light in the red region (Y, La, Gd, Lu) ₂ O ₂ S: Eu And europium activated rare earth oxychalcogenide phosphors represented by the formula:
In addition, the half-value width of the emission peak of the red phosphor is usually in the range of 1 nm to 50 nm.
The red phosphor has an external quantum efficiency of usually 60% or more, preferably 70% or more, and a median diameter D50 is usually about 1 μm.

And a phosphor containing oxynitride and / or oxysulfide containing at least one element selected from the group consisting of Ti, Zr, Hf, Nb, Ta, W and Mo, A phosphor containing an oxynitride having an alpha sialon structure in which some or all of the elements are substituted with Ga elements can also be used. These are phosphors containing oxynitride and / or oxysulfide.
In addition, examples of red phosphors include Eu-activated oxysulfide phosphors such as (La, Y) ₂ O ₂ S: Eu, Y (V, P) O ₄ : Eu, Y ₂ O ₃ : Eu, and the like. Eu-activated oxide phosphors of (Ba, Mg) ₂ SiO ₄ : Eu, Mn, (Ba, Sr, Ca, Mg) ₂ SiO ₄ : Eu, Mn-activated silicate phosphors such as Eu and Mn, Eu-activated tungstate phosphors such as LiW ₂ O ₈ : Eu, LiW ₂ O ₈ : Eu, Sm, Eu ₂ W ₂ O ₉ , Eu ₂ W ₂ O ₉ : Nb, Eu ₂ W ₂ O ₉ : Sm Eu-activated sulfide phosphors such as (Ca, Sr) S: Eu, Eu-activated aluminate phosphors such as YAlO ₃ : Eu, Ca ₂ Y ₈ (SiO ₄ ) ₆ O ₂ : Eu, LiY _{9 (SiO 4) 6 O 2:} Eu, (Sr, Ba, Ca) 3 SiO 5: Eu, Sr 2 BaSiO 5: Eu -activated silicate phosphors such as Eu, _{Y, Gd) 3 Al 5 O} 12: Ce, (Tb, Gd) 3 Al 5 O 12: Ce -activated aluminate phosphor such as Ce, (Mg, Ca, Sr , Ba) 2 Si 5 (N, Eu-activated oxides such as O) ₈ : Eu, (Mg, Ca, Sr, Ba) Si (N, O) ₂ : Eu, (Mg, Ca, Sr, Ba) AlSi (N, O) ₃ : Eu , Nitride or oxynitride phosphor, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu, Mn activated halophosphate phosphor such as Eu, Mn, Ba ₃ MgSi ₂ O ₈ : Eu, Mn, (Ba, Sr, Ca, Mg) ₃ (Zn, Mg) Si ₂ O ₈ : Eu, Mn activated silicate phosphor such as Eu, Mn, 3.5MgO · 0.5MgF ₂ · GeO _2: Mn activated germanate salt phosphors such as Mn, Eu Tsukekatsusan nitride phosphor such as Eu-activated α-sialon, (Gd, Y, Lu, _{a) 2 O 3: Eu,} Eu Bi, etc., Bi-activated oxide phosphor, (Gd, Y, Lu, La) 2 O 2 S: Eu, Eu Bi, etc., Bi Tsukekatsusan sulfide phosphor (Gd, Y, Lu, La) VO ₄ : Eu, Bi activated vanadate phosphors such as Eu and Bi, SrY ₂ S ₄ : Eu and Ce activated sulfide phosphors such as Eu and Ce, CaLa ₂ S ₄ : Ce-activated sulfide phosphor such as Ce, (Ba, Sr, Ca) MgP ₂ O ₇ : Eu, Mn, (Sr, Ca, Ba, Mg, Zn) ₂ P ₂ O ₇ : Eu, Eu, such as Mn, Mn activated phosphate phosphor, (Y, Lu) ₂ WO ₆ : Eu, Mo activated tungstate phosphor such as Eu, Mo, (Ba, Sr, Ca) x Si y Nz: Eu, Ce (where x, y, z represent an integer of 1 or more. Eu, Ce-activated nitride phosphors such as (Ca, Sr, Ba, Mg) ₁₀ (PO ₄ ) ₆ (F, Cl, Br, OH): Eu, Mn-activated halophosphoric acid such as Eu, Mn Salt activated phosphor, Ce-activated silicate fluorescence such as ((Y, Lu, Gd, Tb) ₁ -x-yScxCey) ₂ (Ca, Mg) ₁ -r (Mg, Zn) ²⁺ rSiz-qGeqO ₁₂ + δ It is also possible to use a body or the like.

Examples of red phosphors include β-diketonates, β-diketones, aromatic carboxylic acids, red organic phosphors composed of rare earth element ion complexes having an anion such as Bronsted acid as a ligand, and perylene pigments (for example, Dibenzo {[f, f ′]-4,4 ′, 7,7′-tetraphenyl} diindeno [1,2,3-cd: 1 ′, 2 ′, 3′-lm] perylene), anthraquinone pigment, Lake pigments, azo pigments, quinacridone pigments, anthracene pigments, isoindoline pigments, isoindolinone pigments, phthalocyanine pigments, triphenylmethane basic dyes, indanthrone pigments, indophenol pigments, It is also possible to use a cyanine pigment or a dioxazine pigment.
Among these, as red phosphors, (Ca, Sr, Ba) ₂ Si ₅ (N, O) ₈ : Eu, (Ca, Sr, Ba) Si (N, O) ₂ : Eu, (Ca, Sr , Ba) AlSi (N, O) ₃ : Eu, (Ca, Sr, Ba) AlSi (N, O) ₃ : Ce, (Sr, Ba) ₃ SiO ₅ : Eu, (Ca, Sr) S: Eu, It is preferable to contain (La, Y) ₂ O ₂ S: Eu or Eu complex, more preferably (Ca, Sr, Ba) ₂ Si ₅ (N, O) ₈ : Eu, (Ca, Sr, Ba) Si. (N, O) ₂ : Eu, (Ca, Sr, Ba) AlSi (N, O) ₃ : Eu, (Ca, Sr, Ba) AlSi (N, O) ₃ : Ce, (Sr, Ba) ₃ SiO _{5: Eu, (Ca, Sr} ) S: Eu or _{(La, Y) 2 O 2} S: Eu or Eu (dibenzoylmethane) ₃ · 1, Preferably comprises a β- diketone Eu complex or carboxylic acid type Eu complex such as 10-phenanthroline complex, (Ca, Sr, Ba) 2 Si 5 (N, O) 8: Eu, (Sr, Ca) AlSi ( N, O): Eu or (La, Y) ₂ O ₂ S: Eu is particularly preferred.
Of the above examples, (Sr, Ba) ₃ SiO ₅ : Eu is preferable as the orange phosphor.
In addition, orange or red fluorescent substance may use only 1 type, and may use 2 or more types together by arbitrary combinations and ratios.

(Blue phosphor)
The emission peak wavelength of the blue phosphor is usually 420 nm or more, preferably 430 nm or more, more preferably 440 nm or more, and usually 490 nm or less, preferably 480 nm or less, more preferably 470 nm or less, more preferably 460 nm or less. Preferably it is.
In addition, the half-value width of the emission peak of the blue phosphor is usually in the range of 20 nm to 80 nm.
The blue phosphor has an external quantum efficiency of usually 60% or more, preferably 70% or more, and a median diameter D50 is usually about 1 μm.
Such a blue phosphor is composed of growing particles having a substantially hexagonal shape as a regular crystal growth shape, and europium represented by (Ba, Sr, Ca) MgAl ₁₀ O ₁₇ : Eu that emits light in a blue region. The activated barium magnesium aluminate-based phosphor is composed of growing particles having a substantially spherical shape as a regular crystal growth shape, and emits light in the blue region (Mg, Ca, Sr, Ba) ₅ (PO ₄ ) ₃ (Cl , F): Europium-activated calcium halophosphate phosphor expressed by Eu, and growth particles having a substantially cubic shape as a regular crystal growth shape, and emits light in a blue region (Ca, Sr, Ba) ₂ B ₅ O ₉ Cl: europium-activated alkaline earth aluminate phosphor represented by Eu, which is constituted by fractured particles having a fractured surface, blue-green Emission at a region (Sr, Ca, Ba) Al 2 O 4: Eu or _{(Sr, Ca, Ba) 4} Al 14 O 25: europium-activated alkaline earth represented by Eu aluminate-based phosphor, and the like .

In addition, as the blue phosphor, Sn-activated phosphate phosphors such as Sr ₂ P ₂ O ₇ : Sn, (Sr, Ca, Ba) Al ₂ O ₄ : Eu or (Sr, Ca, Ba) ₄ Al ₁₄ O ₂₅ : Eu, BaMgAl ₁₀ O ₁₇ : Eu, (Ba, Sr, Ca) MgAl ₁₀ O ₁₇ : Eu, BaMgAl ₁₀ O ₁₇ : Eu, Tb, Sm, BaAl ₈ O ₁₃ : Eu attached Active aluminate phosphor, Ce-activated thiogallate phosphor such as SrGa ₂ S ₄ : Ce, CaGa ₂ S ₄ : Ce, Eu, Mn such as (Ba, Sr, Ca) MgAl ₁₀ O ₁₇ : Eu, Mn Active aluminate phosphor, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu, (Ba, Sr, Ca) ₅ (PO ₄ ) ₃ (Cl, F, Br, OH): Eu, Mn, Eu-activated halophosphate phosphors such as Sb, BaAl ₂ Si _{2 8: Eu, (Sr, Ba} ) 3 MgSi 2 O 8: Eu -activated silicate phosphors such as _{Eu, Sr 2 P 2 O 7} : Eu -activated phosphate phosphor such as Eu, ZnS: Ag, ZnS : Sulfide phosphors such as Ag and Al, Y ₂ SiO ₅ : Ce activated silicate phosphors such as Ce, Tungsten phosphors such as CaWO ₄ , (Ba, Sr, Ca) BPO ₅ : Eu, Mn _{, (Sr, Ca) 10 (} PO 4) 6 · nB 2 O 3: Eu, 2 SrO · 0.84P 2 O 5 · 0.16B 2 O 3: Eu, Mn -activated borate phosphate phosphors such as Eu _{body, Sr 2 Si 3 O 8 ·} 2 SrCl 2: Eu activated halo silicate phosphor such as _{Eu, SrSi 9 Al 19 ON 31} : Eu, Eu Tsukekatsusan nitride phosphor such EuSi ₉ Al ₁₉ ON _{31 , La 1 -xCexAl (Si 6 -zAlz} ) (N 10 -zOz) ( wherein, x, and y are each 0 ≦ x ≦ 1, Is a number satisfying ≦ z ≦ 6.), La 1 -x-yCexCayAl (Si 6 -zAlz) (N 10 -zOz) ( wherein, x, y, and z, respectively, 0 ≦ x ≦ 1, It is also possible to use Ce-activated oxynitride phosphors such as 0 ≦ y ≦ 1 and 0 ≦ z ≦ 6.

In addition, as the blue phosphor, for example, naphthalic acid imide-based, benzoxazole-based, styryl-based, coumarin-based, pyralizone-based, triazole-based compound fluorescent dyes, thulium complexes and other organic phosphors can be used. .
Among the above examples, as the blue phosphor, (Ca, Sr, Ba) MgAl ₁₀ O ₁₇ : Eu, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ (Cl, F) ₂ : Eu or (Ba, Ca, Mg, Sr) ₂ SiO \ f ₁₄ : Eu is preferably included, and (Ca, Sr, Ba) MgAl ₁₀ O ₁₇ : Eu, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ (Cl, F) ₂ : Eu or (Ba, Ca, Sr) ₃ MgSi ₂ O ₈ : Eu is more preferable, and BaMgAl ₁₀ O ₁₇ : Eu, Sr ₁₀ (PO ₄ ) ₆ (Cl, F) ₂ : Eu or Ba ₃ MgSi ₂ O ₈ : Eu is more preferable. Of these, (Sr, Ca, Ba, Mg) ₁₀ (PO ₄ ) ₆ Cl ₂ : Eu or (Ca, Sr, Ba) MgAl ₁₀ O ₁₇ : Eu is particularly preferred for illumination and display applications.
In addition, only 1 type may be used for blue fluorescent substance and it may use 2 or more types together by arbitrary combinations and a ratio.
(Yellow phosphor)
The emission peak wavelength of the yellow phosphor is usually in the wavelength range of 530 nm or more, preferably 540 nm or more, more preferably 550 nm or more, and usually 620 nm or less, preferably 600 nm or less, more preferably 580 nm or less. .
Further, the half-value width of the emission peak of the yellow phosphor is usually in the range of 60 nm to 200 nm.
The yellow phosphor has an external quantum efficiency of usually 60% or more, preferably 70% or more, and a median diameter D50 is usually about 1 μm.
Examples of such yellow phosphors include various oxide-based, nitride-based, oxynitride-based, sulfide-based, and oxysulfide-based phosphors.

In particular, RE3M ₅ O ₁₂ : Ce (where RE represents at least one element selected from the group consisting of Y, Tb, Gd, Lu, and Sm, and M consists of Al, Ga, and Sc. Or Ma ₃ Mb ₂ Mc ₃ O ₁₂ : Ce (where Ma is a divalent metal element, Mb is a trivalent metal element, and Mc is a tetravalent metal). A garnet-based phosphor having a garnet structure represented by AE ₂ MdO ₄ : Eu (where AE is at least one selected from the group consisting of Ba, Sr, Ca, Mg, and Zn) And Md represents Si and / or Ge.) Orthosilicate phosphors represented by the above, etc., and oxynitrides obtained by substituting part of oxygen of constituent elements of phosphors of these systems with nitrogen -Based phosphor, AEAlSi (N , O) ₃ : Ce (wherein AE represents at least one element selected from the group consisting of Ba, Sr, Ca, Mg and Zn), etc., nitride-based phosphors having a CaAlSiN ₃ structure, etc. And phosphors activated with Ce.
Other examples of yellow phosphors include sulfide-based fluorescence such as CaGa ₂ S ₄ : Eu, (Ca, Sr) Ga ₂ S ₄ : Eu, (Ca, Sr) (Ga, Al) ₂ S ₄ : Eu. Body, Ca x (Si, Al) ₁₂ (O, N) ₁₆ : a phosphor activated by Eu such as an oxynitride phosphor having a sialon structure such as Eu, (M ₁ -a-bEuaMnb) ₂ (BO ₃ ) _1- p (PO ₄ ) pX (wherein M represents one or more elements selected from the group consisting of Ca, Sr, and Ba, and X is selected from the group consisting of F, Cl, and Br) A, b, and p each represent a number that satisfies 0.001 ≦ a ≦ 0.3, 0 ≦ b ≦ 0.3, and 0 ≦ p ≦ 0.2. It is also possible to use a Eu-activated or Eu-Mn co-activated halogenated borate phosphor.
Examples of yellow phosphors include brilliant sulfoflavine FF (Color Index Number 56205), basic yellow HG (Color Index Number 46040), eosine (Color Index Number 45G80), 45G Etc. can also be used.

Furthermore, a bis (triazinylamino) stilbene disulfonic acid derivative, a bisstyryl biphenyl derivative (ultraviolet excitation 400 to 450 nm fluorescence), or the like can also be used.
In particular, the nano fluorescent material: Si nano fluorescent material, ZnS nanophosphors, YAG: Ce nanophosphors, LaPO _4: Ln nanophosphors, dye-doped silica nanoparticles phosphors, semiconductor nanoparticles, CdSe-ZnS quantum dots or the like, the Since the particle diameter is much smaller than the relief period of the hologram relief, it can be formed uniformly on the relief surface, and the formation thickness is easy to control. When the semiconductor thin film is formed by ultra-fine processing, the semiconductor thin film can be formed with high precision and an ultra-thin film, and the coherence can be improved by controlling the waveform and intensity of the emitted light.
In the fluorescent semiconductor quantum dot, the central core (core) is made of, for example, cadmium selenide (CdSe), and the outer side thereof is covered with a zinc sulfide (ZnS) coating layer (shell). Yes. By changing the diameter of the metal compound, the emitted fluorescence wavelength changes. Since the biopolymer arranged around the quantum dot has a reactive group peculiar to the biopolymer, the phosphor can be specifically arranged using the reactive group.
As the ultraviolet light-emitting phosphor, the peak of the fluorescence spectrum that is emitted when excited by ultraviolet light and returns to a lower energy level is in a wavelength region such as blue, green, and red. Examples of such ultraviolet light-emitting phosphors include Ca ₂ B ₅ O ₉ Cl: Eu ²⁺ , CaWO ₄ , ZnO: Zn, Zn ₂ SiO ₄ : Mn, Y ₂ O ₂ S: Eu, ZnS: Ag. YVO ₄ : Eu, Y ₂ O ₃ : Eu, Gd ₂ O ₂ S: Tb, La ₂ O ₂ S: Tb, Y ₃ Al ₅ O ₁₂ : Ce, etc. Several of these are mixed and used at an appropriate ratio.
These have peaks in the fluorescence spectrum outside the blue, red, and green wavelength regions. Further, the weight ratio of the ultraviolet fluorescent substance in the ink is not limited as long as the fluorescence can be detected by the light receiving element of the reading head.
On the other hand, some infrared light emitting phosphors have the property of receiving visible light having a wavelength λ2 upon receiving excitation light having a wavelength λ1, and having the properties of λ1 = λ2 and λ1> λ2. Examples of such infrared light emitting phosphors include YF ₃ : Yb, Er, ZnS: CuCO, and the like.

Specific examples include Lumogen FV Violet 570 (Naphthalimide: 374 nm → 413 nm), Lumogen F Yellow 083 (perylene: excitation wavelength 476 nm → emission wavelength 490 nm: the same applies hereinafter), Lumogen F orange (perylene: 525 nm → 539 nm). ), Lumogen F Red 305 (perylene: 578 nm → 613 nm), etc.
Fluorescent pigments manufactured by Deigro: Gropril T / GT series, ACT series, Z / ZQ series, GPL series, LHY series, Fluorescent dyes: DIVELIGHT D-818 Roanoke yellow, D-784 ALPARTA yellow, D-208 APACHI yellow D-288 Cherokee Red, D-688 Colorado Red, D-298 Columbia Blue, etc.
Fluorescent pigments manufactured by Sinloi: Sinroicolor FZ-2000 series (FZ-2001RED, etc.), FZ-2800 series (FZ-2808 Blue, etc.), SX-100 series (SX-104 Orange, etc.), SX-1000 series (SX-1004 Orange) SX-1005 Lemon Yellow, SX-1007 Pink, SX-1037 Magenta: average particle size 1.0 μm or less, SW-10 series (SW-11 Red Orange, SW-12NG Green, SW-13 Red Orange, SW-14 NO Orange, SW-15N Lemon Yellow , SW-16N Orange Yellow, SW-07Cerise, SW-17Pink, SW-27Rose, SW-37Rubine, SW-47Viole , SW-28Blue: average particle size 1.0 μm or less), SP series, SF-3000 series (ultrafine particle type), SF-5000 series (ultrafine particle type), SF-8000 series (ultrafine particle type), Lumilite Nano RY202 ( Particle size 30 nm, 365-370 nm → 619 nm), etc.

Manufactured by Moritechx Co., Ltd .: fluorescent particles (green: 468 nm → 508 nm) G25 (particle size 0.03 μm), G40 (particle size 0.04 μm), G50 (particle size 0.05 μm), G75 (particle size 0.07 μm), G85 (particle size 0.09 μm), G100 (particle size 0.10 μm), G140 (particle size 0.14 μm), G200 (particle size 0.20 μm), G250 (particle size 0.25 μm), G300 (particle size 0) .30 μm), G400 (particle size 0.40 μm), G450 (particle size 0.45 μm), G500 (particle size 0.50 μm),
Fluorescent particles (green: 360 nm → 530 nm) 34-1 (average particle size 3.0 μm),
Fluorescent particles (blue: 365 nm → 447 nm) B50 (particle size 0.05 μm), B100 (particle size 0.10 μm), B150 (particle size 0.14 μm), B200 (particle size 0.20 μm), B300 (particle size 0) .30 μm), B400 (particle size 0.40 μm), B500 (particle size 0.50 μm),
Fluorescent particles (red: 542 nm → 612 nm) B50 (particle size 0.05 μm), B60 (particle size 0.05 μm), B100 (particle size 0.10 μm), B160 (particle size 0.16 μm), B200 (particle size 0) .20 μm), B300 (particle size 0.30 μm), B400 (particle size 0.40 μm), B500 (particle size 0.50 μm), etc.
UV excitation fluorescent pigments UVP-1 (emission wavelength 421 nm), UVB-1 (emission wavelength 453 nm), UVG-2 (emission wavelength 517 nm), UVR-2 (emission wavelength 626 nm), visible light excitation fluorescent pigment LMS-570 (450-520 nm → 570 nm), LMS-560 (450-467 nm → 560 nm), LMS-550 (450-465 nm → 550 nm), LMS-540 (450-465 nm → 540 nm), etc.
Qdot525 nanocrystal (350-488 nm → 525 nm), Qdot565 nanocrystal (350-488 nm → 565 nm), Qdot585 nanocrystal (350-488 nm → 585 nm), Qdot605 nanocrystal (350-488 nm → 605 nm), Qdot625 nano Crystal (350-488 nm → 625 nm), Qdot655 nanocrystal (350-488 nm → 655 nm), Qdot705 nanocrystal (350-488 nm → 705 nm), Qdot800 nanocrystal (350-488 nm → 800 nm), etc.
Evidot manufactured by Evident Technologies, Inc .: CdSe / ZnS core shell Evidot (average particle size 7.2 to 9.6 nm, emission wavelength 490 nm to 620 nm), etc.
Quantum dots manufactured by Nippon Quantum Design Co., Ltd .: carboxyl group type, amino group type: diameters of 3.0 nm to 8.3 nm and emission wavelengths of 530 nm to 620 nm can be suitably used.

Next, the principle of holography will be described.
If an object is illuminated with coherent light and light diffracted from the object illuminates a recording medium (photoresist, etc.), the object wave is diffracted from the object and reaches the recording surface.
F (x, y) = A (x, y) EXP [φ (x, y)]
It is expressed. here,
A (x, y) is the amplitude distribution of the object wave,
φ (x, y) is a phase distribution.
At this time, the intensity distribution of the light wave reaching the recording medium is recorded on the recording medium. Its intensity distribution is
I (x, y) = | F (x, y) | ² = A ² (x, y) (1)
Thus, the phase distribution is not recorded.
Here, when an object wave and a coherent light wave (referred to as a reference wave) are superimposed, the intensity distribution of the recorded light wave is
I (x, y) = | F (x, y) + R (x, y) | ²
= | F (x, y) | ² + | R (x, y) | ²
+ F (x, y) R ^* (x, y) + F ^* (x, y) R (x, y) (2)
It becomes. (* Represents a complex conjugate term.)

However, if the reference light is a plane wave incident on the recording surface at an angle θ,
R (x, y) = r (x, y) EXP (2πiαx) (3)
Write,
α = SIN (θ) / λ (4)
It is. In the first and second terms of (2), the phase information is missing for both the intensity of the object wave and the intensity of the reference wave. The third term and the fourth term are interference terms. F (x, y) R * (x, y) =
A (x, y) r (x, y) EXP [i [φ (x, y) -2παx]] (5)
F * (x, y) R (x, y) =
A (x, y) r (x, y) EXP [-i [[phi] (x, y) -2 [pi] [alpha] x]] (6)
The phase term φ (x, y) of the object remains. (5) and (6) are complex conjugates of each other, and the third term in (4.2) includes the complex amplitude distribution of the object. Substituting (5) and (6) into (2),
I (x, y) = | F (x, y) | ² + | R (x, y) | ²
+ 2A (x, y) r (x, y) COS [2παx−φ (x, y)] (7)
It becomes. It can be seen that the object wave and the reference wave interfere to form an interference fringe.

In this way, holography is a method in which a reference wave is superimposed on an object wave and interference recording is performed, and the phase information of the object is recorded without being lost. A recording of (7) is called a “hologram”. The intensity transmission or amplitude reflectance of the hologram is the recorded intensity distribution I (x, y)
Proportional,
T (x, y) = τI (x, y) (8)
Let's call it. When the reference wave used when recording on this hologram is at a predetermined angle, the wavefront transmitted or reflected by the hologram is
T (x, y) R (x, y) = τ (| F (x, y) | ² + | R (x, y) | ² )
+ ΤF (x, y) | R (x, y) | ²
+ ΤF ^* (x, y) R ² (x, y) (9)
Can be expressed. This second term is τF (x, y) | R (x, y) | ² =
τA (x, y) r ² (x, y) EXP [iφ (x, y)]] (10)
The third term is
τF * (x, y) R ² (x, y) =
τA (x, y) r ² (x, y) EXP [−iφ (x, y) + 2πiα] (11)
Call it.

Therefore, the first term of (9) is a light beam penetrating the hologram in the same direction as the illumination light or a specularly reflected light beam, and the second term is a light wave having an amplitude proportional to the object light from (10). From (11), it can be seen that the third term is a light wave having a phase distribution conjugate with the object wave and propagating in the direction of 2θ.
In this way, the complex amplitude distribution can be recorded and reproduced using the holographic technique.
In the case of the present invention, the amplitude transmittance or reflectance of the hologram is proportional to the recorded intensity distribution and is expressed by the equation (8), but the reference wave used when recording on this hologram. Is not a predetermined angle, but a light-emitting wave having a spatial distribution similar to the amplitude transmittance or amplitude reflectance of (8) is emitted from this hologram.
Therefore, the emission wave is emitted while maintaining the phase term already recorded in the hologram, regardless of the conventional principle of hologram reproduction in which the phase term recorded in the hologram is given to the reference light. Therefore, theoretically, it has a three-dimensional continuous curved light emitting surface having a spatial function including the phase difference of an object, and light is emitted from the one curved surface.

To simplify the conventional hologram reproduction principle for the transmission type, when parallel light as reference light is applied to the hologram, the parallel light is shielded in the shielding part, and the parallel light is transmitted only from the transmission part. Diffraction occurs at the boundary between the transmission part and the shielding part, receives the phase term of the object, and the entire component transmitted through the hologram is superimposed, which becomes the hologram reproduction light and reaches the observer's eyes.
In the case of the present invention, there is no parallel light as the reference light described above, and the emitted light retains the phase term of the object when emitting light on the light emitting surface provided in contact with the hologram relief. Hologram reproduction is performed by an interference phenomenon between radiated lights.
The interference effect between synchrotron radiation without temporal and spatial coherence does not cause sufficient interference like laser light, but hologram reproduction is performed at the same level as when a hologram is illuminated with low coherent light. . Since the reproduction is based on the principle as described above, the reference light at the time of hologram photographing is preferably parallel light (because complicated reference light cannot be reproduced), or “hologram represented by a diffraction grating” (diffraction The grating is preferably both object light and reference light.) The diffraction grating formed by electron beam drawing, such as a computer generated hologram, is precise and suitable.

Further, for the above reason, in order to make the hologram reproduction image clearer, it is necessary to give the radiation light a characteristic similar to temporal or spatial coherence, for example, the light emitting surface of the light emitter. It is desirable to reduce the thickness of the light emission and to narrow the emission wavelength width. Further, the excitation light source is also preferably a small shape, and a spot shape or the like is particularly suitable.
In addition, it is desirable that the wavelength difference between the excitation light for exciting the illuminant and the emission wavelength is large, and it is also effective to amplify only the emission light by filtering the excitation light during observation.
As an excitation light source, energy such as ultraviolet rays, visible rays, electron beams, X-rays and the like, and depending on the case, a light source capable of emitting infrared energy can be used to emit fluorescence, etc. In order to use it for hologram authentication, it is necessary to use a light source corresponding to the phosphor, and an ultraviolet light source, a visible light source having a predetermined intensity, wavelength and size of an illumination spot, a visible light source, and in some cases an infrared light source are used.
From the fluorescent layer provided so as to be in contact with the hologram relief surface by illumination by these light sources, and more specifically, from the phosphor contained in the fluorescent layer, fluorescence of a wavelength different from the wavelength of the illumination light source, etc. To express. Since the fluorescence emission and the like have the same spatial phase as the hologram relief and have a wavelength (fluorescence wavelength) different from that of the illumination light source, the direction of specularly reflected light (0th order diffracted light) by the hologram relief, illumination The hologram image is reproduced in a direction different from the diffraction direction by the light wavelength (excitation light wavelength), that is, in the diffraction direction by the fluorescence wavelength.

However, when the thickness of the fluorescent layer is distributed on the hologram surface irrespective of the hologram relief, the fluorescence emission intensity distribution resulting from the thickness distribution may be reproduced in some cases. Unnecessary interference with light can occur, which can be a cause of blurring of the hologram reproduction image.
In order to eliminate this factor, the fluorescent layer is formed with a uniform thickness following the irregularities forming the hologram relief so that light emission of the same intensity can be generated from any position on the hologram relief surface. The reproduced image can be sharpened.
When ultraviolet light or infrared light other than visible light is used as the illumination light (excitation light) of the hologram sheet of the present invention, the light is not visible to the observer, and the hologram reproduction image is seen from the place where there is no illumination light. However, even if the illumination light is temporally and spatially coherent, as a result, this hologram reconstructed image emits light through a process of excitation and fluorescence. Therefore, the temporal and spatial coherence between the emitted lights is small, although the phase of the spatial hologram at the time of emission is included, the hologram reproduction image is a normal laser reproduction relief hologram. It is weaker than the reproduced image and is unclear.
Of course, if only observing the beam-shaped diffracted light, it is easy to check its color tone and diffraction direction, and it can be used as it is to determine the authenticity, but this weak and unclear hologram reproduction. In order to allow the observer to recognize the image and accurately determine its presence, the luminous performance of the phosphor is improved, and the diffraction angle is increased to increase the wavelength-diffraction angle dependency. It is necessary to increase the difference in the fluorescent light diffraction angle and further reduce the thickness of the fluorescent layer to suppress variation in the thickness direction of the fluorescent layer and make it uniform. (Since the light emitting surface contains phase information, its spatial shape is accurately reproduced.)

Furthermore, in order to express temporal coherence, excitation is performed with a pulse laser of 10 ⁻¹⁵ sec or less as a light source, and illumination is performed with a time interval between pulses of 10 ⁻⁷ sec or more that is a fluorescence emission time. It is also suitable. Thus, one fluorescent light emitting surface generated by one excitation pulse does not cause a disturbance phenomenon with the fluorescent light emitting surface generated by the next excitation pulse, and one fluorescent light emitting surface expressed by one pulse. Due to the holographic interference phenomenon caused by the above, a clear hologram reproduction image can be observed. Of course, even if a strobe light source that is simply turned on and off in seconds is used, the viewer seems to emit light continuously. When confirming with the above, the above-described effects can be sufficiently obtained.
The fluorescent layer uses fluorescent ink in which phosphor is mixed in resin or dispersed in solvent (or water) on the hologram relief by gravure method, offset method, silk screen method, nozzle coating method, ink jet method, etc. Can be formed.
At this time, by adjusting the content ratio of the phosphor in the fluorescent ink, the formed fluorescent layer can be formed with a uniform thickness following the unevenness forming the hologram relief.
The unevenness of the hologram relief is, for example, a gentle curve having an unevenness of a depth of 0.01 μm with a period of 1 μm level and can be regarded as a substantially flat surface. 1 to 10 pascals / second), exhibiting the leveling effect due to the weight of the ink itself, and by setting the solid content in the ink to 20% or less, further 10% or less, for example, for a thickness of 1 μm The variation can be suppressed to 1/10 or less, and further to 1/20 or less.

Here, although the fluorescent layer is on the order of 1 μm, in order to improve the clarity of the hologram reproduction image, it is preferable to make the fluorescent layer thin. For this purpose, the size of the phosphor is about 1.0 μm or less. Hereinafter, for example, 0.1 μm to 0.5 μm, more preferably 0.5 μm to 0.1 μm, more preferably 3 to 10 nm, and the dots are uniformly scattered in the hologram relief surface, and the thickness direction of the fluorescent layer In this case, it is preferable that the phosphor is arranged in the order of 1 to 10 particles or 1 to 3 particles as a unit.
In particular, the nozzle coating method and the ink jet method can be formed only with a solvent and a phosphor without using a resin, and can be formed very thin as a phosphor layer (for one to three phosphors, etc.). Therefore, it is preferable. A resin may be formed thereon to fix the phosphors.
In order to increase the clarity of the hologram reproduction image based on the above-mentioned hologram principle, it is desirable that the thickness of the fluorescent layer is thin. However, the thinner the thickness, the lower the fluorescence emission intensity during hologram reproduction. The layer thickness needs to be 0.01 μm or more and 0.1 μm or less.
If it is less than 0.01 μm (0.003 μm for one phosphor with the smallest particle size), the fluorescence emission intensity is too weak, and even if amplified using a photomultiplier tube, it can be distinguished from noise such as stray light. When the thickness exceeds 0.1 μm, depending on the formation process of the fluorescent layer, the “relief shape” on the side of the fluorescent layer not in contact with the transparent resin layer having the hologram relief and the “hologram relief of the fluorescent layer” The “relief shape” on the “side in contact with the transparent resin layer” is not substantially the same. Therefore, the thickness of the fluorescent layer is set to 2.0 μm or less, preferably 0.1 μm or less.
That is, the “relief shape” of “the side not in contact with the transparent resin layer having the hologram relief” of the fluorescent layer and the “relief shape” of the “hologram relief” provided on the transparent resin layer having the hologram relief. In the meantime, a “deviation” occurs.

This “deviation” is likely to occur in the depth direction of the “relief shape”, and the “displacement size” increases as the fluorescent layer becomes thicker.
“Deviation in the depth direction” in the hologram relief strongly affects the “brightness” of the hologram reproduction image, and the depth of the hologram relief is “the optimum depth (the depth at which the brightest hologram reproduction image can be reproduced). ")", Even if it becomes evenly shallower or even deeper, the "brightness" will decrease.
In order to minimize this "displacement", first, a "transparent layer with a uniform thickness" is formed on a transparent substrate, and a "fluorescent layer with a uniform thickness" is formed on the transparent layer. ”.
At this time, a transparent substrate having a high surface smoothness (for example, its surface roughness: Ra is 0.01 μm or less) is used, and a transparent resin material is used on the surface thereof, so that the thickness is 1 μm to 10 μm. Provided with a “transparent layer having a uniform thickness” with a thickness accuracy within ± 1%, and a fluorescent layer is formed thereon with a thickness of 0.01 μm to 2.0 μm. A “uniformly-thickness fluorescent layer” with an accuracy of within ± 5% is provided.
The plane in contact with the fluorescent layer of this “transparent layer of uniform thickness” is changed to the “relief shape” of “hologram relief” by the following deformation, and the “transparent layer of uniform thickness” It becomes “a transparent resin layer having a hologram relief including a diffraction grating group corresponding to a hologram image”. Usually, the transparent resin layer is formed to a thickness of 1 μm to 30 μm, and the transparent resin layer is formed thinner to achieve a more uniform thickness.
Such “uniformity” can be obtained by a precision coating method such as a spin coating method. In the ink composition to be used, the solid content in the ink is set as low as 0.5% to 5.0%. A method of making the thickness unevenness of the coating film before drying to be 1/20 to 1/200 by performing gentle drying after applying the ink can also be used.
For example, a transparent resin layer having a thickness of 3 μm is provided with a thickness accuracy of ± 1%, that is, a thickness unevenness of ± 0.03 μm or less, and a fluorescent layer having a thickness of 1.0 μm is formed thereon. Accuracy is ± 5%, that is, with a thickness variation of ± 0.05μm or less, “Transparent layer with uniform thickness” and “Fluorescent layer with uniform thickness” on “Transparent substrate” Are formed in layers.

An original plate (press mold) provided with a hologram relief in advance on the outermost surface of the fluorescent layer is pressed against the two uniform layers, and appropriate heating and pressurization are applied to the two uniform layers. In the “transparent layer of uniform thickness”, only the surface side that is in contact with the “fluorescent layer of uniform thickness” and in the “fluorescent layer of uniform thickness” The “fluorescent layer having a uniform thickness” itself is referred to as a “relief shape”.
As a result, the “hologram relief” formed on the interface between the “transparent layer with uniform thickness” and the “fluorescent layer with uniform thickness” and the outermost surface of the “fluorescent layer with uniform thickness” This is the same as the “hologram relief” provided in the mold with high accuracy, and the surface shape of the total reflective layer formed on the outermost surface of this “uniform thickness fluorescent layer” is also highly accurate. It can be the “hologram relief” itself.
As a result, the light reflected by the total reflection thin film layer reproduces a very clear hologram reproduction image.
The total reflective thin film layer can be provided with a thickness of 100 nm to 2000 nm by vapor deposition or a vacuum thin film method such as CVD (chemical vapor deposition).
In addition, since the formation thickness accuracy of the “totally reflective thin film layer” is very high and the formation thickness itself is very thin, the above “uniform two layers” are formed and then “total reflection” In the same manner as described above, a master plate (press mold) provided with a hologram relief in advance is pressed from the outermost surface of this “totally reflective thin film layer”, and appropriate heating and pressurization are applied. Then, the three layers are deformed, the surface side of the “transparent layer of uniform thickness” in contact with the “phosphor layer”, the “uniform thickness of phosphor layer” itself, and the total reflection thin film layer It is also preferable to adopt the “relief shape” at the same time. When this method is used, the “relief shape” of the fluorescent layer, which is likely to occur when a total reflective thin film layer is formed on the fluorescent layer already in the hologram relief shape, The hologram relief deterioration factor such as part adhesion (partially removed) can be eliminated, which is preferable.
In the hologram sheet of the present invention, light emission from the fluorescent layer is blocked by the total reflection thin film layer, and also blocks ultraviolet rays and the like, so that a hologram reproduction image by fluorescence emission is observed only from one surface of the hologram sheet. However, it is assumed that the hologram reproduction image by fluorescence emission can be observed from the other surface of the hologram sheet by further providing a fluorescent layer on the total reflection thin film layer. In that case, the position (region) where the two fluorescent layers are provided can be different, and the hologram reproduction images by the respective fluorescence emission can be different. It is suitable for increasing.
Further, an appropriate pressure-sensitive adhesive layer is formed on the total reflective thin film layer and used as a “label”, or an appropriate release layer is provided on an appropriate substrate, and a transparent film having a hologram relief thereon. It is also suitable to use as a “transfer foil” provided with a resin layer, a fluorescent layer, a transparent reflective thin film layer, and an appropriate adhesive layer.

According to the hologram sheet of the present invention,
On one surface of the transparent substrate, a transparent resin layer having a hologram relief including a diffraction grating group corresponding to a hologram image, a fluorescent layer provided in contact with the hologram relief, and a total reflection thin film layer, A hologram sheet provided in this order is provided. Under natural light, the hologram reproduction image can be visually recognized by the reflected light from the total reflection thin film layer, and at first glance, it can be observed like a normal hologram sheet, but is defined. In addition, a novel hologram sheet is provided in which a hologram reproduction image having only a specific wavelength different from the wavelength appears in a specific direction by illumination of a light source having a predetermined wavelength.

Is a Jablonsky diagram. These are sectional drawings of hologram sheet A showing one example of the present invention. (This is an example in which the fluorescent layer is “formed with a uniform thickness following the concavities and convexities forming the hologram relief”, and the illustration in the case where the fluorescent layer is provided so as to be in contact with the fluorescent layer is omitted.) Is a process for determining an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
(Transparent substrate) The transparent substrate 1 used in the present invention can be reduced in thickness, and can withstand mechanical strength and solvent resistance and heat resistance that can withstand processing when manufacturing the hologram sheet A. Those having the following are preferred. Since it depends on the purpose of use, it is not limited, but a film-like or sheet-like plastic is preferable. (See Figure 2.)
For example, various plastic films such as polyethylene terephthalate (PET), polycarbonate, polyvinyl alcohol, polysulfone, polyethylene, polypropylene, polystyrene, polyarylate, triacetyl cellulose (TAC), diacetyl cellulose, and polyethylene / vinyl alcohol can be exemplified. .
Among them, those having resistance to excitation light such as ultraviolet rays, for example, those containing ultraviolet absorbers may be used. Those containing an ultraviolet absorber also have an effect of preventing unplanned hologram reproduction, although it is faint due to ultraviolet rays contained in natural light or the like.
The thickness of the transparent substrate 1 is usually 5 to 100 μm, but in view of the visibility of the hologram reproduction image, it is preferably 5 to 50 μm, particularly 5 to 25 μm.

(Transparent resin layer having hologram relief including diffraction grating group corresponding to hologram image: also called hologram forming layer.)
As the transparent resin material for constituting the hologram forming layer 2 of the present invention, various thermoplastic resins, thermosetting resins, or ionizing radiation curable resins can be used. (See Figure 2.)
Thermoplastic resins include acrylic ester resins, acrylamide resins, nitrocellulose resins, or polystyrene resins. Thermosetting resins include unsaturated polyester resins, acrylic urethane resins, epoxy-modified acrylic resins, and epoxy-modified unsaturated resins. A polyester resin, an alkyd resin, a phenol resin, etc. are mentioned.
These thermoplastic resins and thermosetting resins can be used alone or in combination of two or more. One or more of these resins may be cross-linked using various isocyanate resins, or various curing catalysts, for example, metal soap such as cobalt naphthenate or zinc naphthenate may be blended. Or peroxide such as benzoyl peroxide and methyl ethyl ketone peroxide for initiating polymerization with heat or ultraviolet light, benzophenone, acetophenone, anthraquinone, naphthoquinone, azobisisobutyronitrile, or diphenyl sulfide good.
Examples of the ionizing radiation curable resin include epoxy acrylate, urethane acrylate, acrylic-modified polyester, etc., for the purpose of introducing a crosslinked structure into such an ionizing radiation curable resin or adjusting the viscosity, A monofunctional monomer, a polyfunctional monomer, or an oligomer may be blended and used.
In order to form the hologram forming layer 2 using the above-mentioned resin material, it can be directly formed by developing the photosensitive resin material by performing interference exposure of the hologram. It is preferable to perform molding by using a replica or a plating mold thereof as a replica mold and pressing the mold surface against the layer of the resin material.

When thermosetting resin or ionizing radiation curable resin is used, curing is performed by heating or ionizing radiation irradiation while keeping the uncured resin in close contact with the mold surface, and then cured by peeling after curing. The fine irregularities of the relief hologram can be formed on one side of the layer made of a transparent resin material. A diffraction grating forming layer having a diffraction grating formed in a pattern by a similar method can also be used as the optical diffraction structure.
The thickness of the hologram forming layer 2 is 1 μm to 30 μm, particularly 3 μm to 10 μm.
If the thickness is less than 1 μm, it is difficult to form a “relief shape”, and if it exceeds 30 μm, the “relief shape” due to thermal expansion or thermal deformation of the hologram forming layer 2 due to the processing process or usage environment of the hologram sheet. Degradation is likely to occur. When the thickness of the hologram forming layer 2 is 3 μm to 10 μm, it is excellent in handling suitability during the processing step and in use, and the uniformity can be improved.
A hologram is a recording of interference fringes due to the interference of light between object light and reference light in an uneven relief shape. For example, laser reproduction holograms such as Fresnel holograms, white light reproduction holograms such as rainbow holograms, There are color holograms utilizing the above principle, computer generated holograms (CGH), holographic diffraction gratings and the like. Further, like a machine readable hologram, the reproduction light may be converted into data by a light receiving unit and transmitted as predetermined information, or authenticity may be determined. (The hologram forming process is not shown.)
In particular, a hologram H1 capable of observing the hologram reproduction image A1 with natural light such as a white light reproduction hologram or normal illumination light such as a fluorescent lamp, and a hologram H2 capable of reproducing the hologram reproduction image A2 only with single wavelength light such as a Fresnel hologram. By multiplex recording as one hologram relief, when observing the hologram sheet of the present invention with normal illumination light, only the hologram reproduction image A1 can be visually recognized, and when illuminating light of a predetermined wavelength is applied, It is also preferable to make it possible to visually recognize the hologram reproduction image A2, which is a hologram of the above.

Further, when the illumination light having the predetermined wavelength is a light source that is not preferable to enter the eyes of an observer such as ultraviolet rays, the ultraviolet rays are reflected by the total reflection reflecting layer 4. In order to avoid entering the eyes, the incident angle is adjusted so that the reflected light travels in a direction significantly different from the direction of observation (the incident angle on the hologram sheet is set relative to the direction perpendicular to the hologram sheet surface). ± 60 degrees to ± 80 degrees, or when the illumination angle for reproducing the hologram reproduction image is above the hologram sheet and the reproduction angle is below it, the hologram sheet is incident from the right direction. It is also preferable that the light be reflected in the left direction.
Moreover, since the reproduction direction of the hologram reproduction image A2 is constant even if the angle at which the predetermined illumination light is applied is changed, the authenticity of the hologram reproduction image A2 can be determined easily and accurately.
In order to precisely create fine irregularities, not only optical methods, but also electron beam lithography equipment can be used to create precisely designed relief structures that produce more precise and complex reproduction light. Good. The relief shape is designed to have a pitch, depth, or specific periodic shape of the unevenness according to the wavelength (range) of the light or light source for reproducing or reproducing the hologram, the direction and the intensity of reproduction or reproduction.
In addition, a color hologram image is formed by a diffraction grating pixel consisting of diffraction grating lines (a minimum unit of a single diffraction grating area consisting of the same diffraction grating line. A set of light emitted from these pixels as diffracted light is one color hologram image. Such a hologram relief is a typical example including a diffraction grating group corresponding to a hologram image.), And a predetermined pixel size, grating line pitch, and grating line angle are set for each element. It is also possible to form the image by using an image processing method of assigning to elements and reproducing.
The pitch (period) of the unevenness depends on the reproduction or reproduction angle, but is usually 0.1 μm to several μm, and the depth of the unevenness is a factor that greatly affects the reproduction or reproduction intensity, but is usually 0.01 μm. ˜0.5 μm.

As in the case of a single diffraction grating, when the unevenness of exactly the same shape is repeated, as the adjacent unevenness is the same shape, the degree of interference of reflected light increases and the intensity increases, and the maximum value is reached. Converge. The blur in the diffraction direction is also minimized. When a single point of an image converges to a focal point, such as a stereoscopic image, the convergence accuracy to the focal point is improved, and a reproduced or reproduced image becomes clear.
The method of shaping (also called replicating) the hologram relief shape is as follows. A master plate on which diffraction gratings and interference fringes are recorded in a concavo-convex shape is used as a press mold (also called a stamper). The concavo-convex pattern of the original plate can be duplicated by stacking the original plate and heat-pressing both of them with an appropriate means such as a heating roll. The hologram pattern to be formed may be single or plural.
In order to accurately reproduce the above-mentioned extremely fine shape and to minimize distortion and deformation such as heat shrinkage after replication, the original plate is made of metal and replicated at low temperature and high pressure.
For the original plate, a metal having high hardness such as Ni is used. After a Cr or Ni thin film layer is formed on the surface of a glass master or the like formed by optical imaging or electron beam drawing or the like by vacuum deposition or sputtering, Ni or the like is electrodeposited (electroplating, electroless plating) Further, it can be made by peeling the metal after forming 50 to 1000 μm by composite plating or the like.
The duplication method uses a flat plate type or a rotary type, the linear pressure is 0.1 ton / m to 10 ton / m, and the duplication temperature is usually 60 ° C. to 200 ° C. (The replication process is not shown.)
Then, using the above-described method for shaping (replicating) the hologram relief shape, a “transparent layer having a uniform thickness” (not shown. This “transparent layer”) is formed on the transparent substrate 1 in advance. Becomes the hologram forming layer 2 of the hologram sheet A of the present invention, and “a fluorescent layer having a uniform thickness” (not shown) is formed on the transparent layer. Is formed on the fluorescent layer 3 of the uniform thickness, and the above-described original plate is stacked and heated and pressed by appropriate means such as a heating roll to form unevenness of the original plate. It is also preferable that the pattern is provided on the “transparent layer having a uniform thickness” to be the hologram forming layer 2 and the pattern is provided on the “fluorescent layer having a uniform thickness” to be the fluorescent layer 3.
At this time, the transparent substrate 1 has high heat resistance and pressure resistance, and is not subjected to any deformation by this heating and pressurization.
Furthermore, although “transparent layer with uniform thickness”, “fluorescent layer with uniform thickness”, and “metal thin film layer having total reflection” are formed on transparent substrate 1 in advance (4 Similarly, a method of forming a hologram relief shape from above the metal thin film layer and providing the hologram forming layer 2, the fluorescent layer 3, and the total reflection thin film layer 4 is also suitable. is there.

(Fluorescent layer)
In the present invention, the fluorescent layer 3 is formed on the hologram relief surface of the hologram forming layer 2. (See Figure 2.)
This fluorescent layer 3 is produced by using a resin-dispersed fluorescent ink in which the phosphor is uniformly dispersed in a transparent resin, or a solvent-dispersed fluorescent ink in which the phosphor is dispersed in water or a solvent. By using various forming methods such as a method, a coating method, and an ink jet method, the hologram forming layer 2 can be uniformly formed so as to be in contact with and follow the hologram relief.
The resin-dispersed fluorescent ink includes the above-described phosphor, a transparent resin, for example, an acrylic ester resin, an acrylamide resin, a nitrocellulose resin, or a polystyrene resin as a thermoplastic resin, and a thermosetting resin. Ball mills and kneaders using glass beads or steel beads to reduce secondary aggregation in unsaturated polyester resins, acrylic urethane resins, epoxy-modified acrylic resins, epoxy-modified unsaturated polyester resins, alkyd resins, or phenol resins Thoroughly kneading with a roll mill, etc., adjusting the viscosity with a solvent, etc., and using a gravure method, offset method, silk screen method, curtain coating method, nozzle coating method, and even an ink jet method as appropriate, a uniform thickness Can be formed.
The thickness of the fluorescent layer 3 is 0.01 μm or more and 2.0 μm or less, and preferably 0.01 μm or more and 0.1 μm or less.
In order to set the thickness of the fluorescent layer 3 to 0.01 μm or more and 0.1 μm or less, a coating film using a resin-dispersed ink with a solid content of 0.5 to 5.0% and a solvent or water as a solvent is used. For example, when the thickness is 2.0 μm, the thickness after evaporation of the solvent (the thickness of the fluorescent layer) is set to 1/20 to 1/200, and 0.1 μm to 0.01 μm. And

Since the solvent-dispersed fluorescent ink does not include a resin component and includes only a phosphor and a solvent, the thickness of the fluorescent layer 3 can be made thinner than that of the resin-dispersed type.
As a solvent, water, an alcohol solvent, a cellsolve solvent, or a paraffin solvent is used to disperse and hold a small particle phosphor and provided on the hologram forming layer 2 by curtain coating, nozzle coating or the like while stirring. be able to.
In this case, by adjusting the evaporation rate of the solvent, the phosphor can be moved to the recess by its own weight while the solvent is volatilized.
Furthermore, several μm of a slow volatile solvent having solubility is applied to the resin forming the hologram relief surface (a ketone solvent such as cyclohexanone for acrylic, vinyl chloride, vinyl acetate resin, polyester resin, etc.). It is also possible to dilute this solvent with a non-soluble solvent and use it to make the remaining components 0.1 μm or less.) Dissolve only the outermost surface of the hologram relief surface, There is also a method for forming the fluorescent layer 3 by imparting adhesiveness to the surface and spraying the phosphor as powder on the surface so that only the phosphor particles in contact with the adhesive surface remain on the hologram relief surface. Is preferred.
According to this method, the fluorescent layer 3 becomes almost one particle film, is uniformly formed on the hologram relief surface, and the fluorescence emission surface when the excitation light is applied from the hologram forming layer 2 side is the same as the hologram relief surface. .
In any case, since the unevenness of the hologram relief is very small, the fluorescent layer 3 has a uniform thickness and the phosphors in it have a uniform density or evenly on the hologram relief surface (partial In the case of formation, in order to form a uniform portion), it is preferable that the phosphor has a smaller particle diameter, and a nanophosphor is particularly suitable.
(Totally reflective thin film layer)
A total reflection thin film layer 4 is formed on the fluorescent layer 3 to form the hologram sheet A of the present invention. (See Figure 2.)
Since the total reflection thin film layer 4 needs to reflect incident visible light sufficiently, a metal thin film having a visible light reflectance of 90% to 100% is used.

The total reflective thin film layer 4 is provided with a metallic gloss reflection layer such as a metal thin film formed by a vacuum thin film method or the like. When the metal gloss reflection layer is partially provided, the portion without the metal gloss reflection layer is provided. Through this, the other side of the hologram sheet of the present invention can be visually recognized.
Specifically, Be, Mg, Ca, Cr, Mn, Cu, Ag, AL, Sn, In, Te, Ti, Fe, Co, Zn, Ge, Pb, Cd, Bi, Se, Ga, Rb, Sb Pb, Ni, Sr, Ba, La, Ce, W, Au and the like can be exemplified, and those having excellent adhesiveness with the fluorescent layer 3 are used.
Also, a metal thin film having high reflection over almost the entire visible light wavelength, that is, a “total reflection” property, is transparent due to its thickness, that is, when its thickness is less than 100 nm (ie, This is because the reflectance decreases, the brightness of the hologram reproduction image observed under natural light decreases, and the background of the hologram sheet overlaps with the reproduction image through the hologram sheet, thereby reducing the clarity of the hologram reproduction image.) The thickness is 100 nm to 2000 nm.
If the thickness exceeds 2000 nm, thermal damage to the fluorescent layer 3 in the thin film forming process becomes large, which causes a distortion of the “relief shape” of the fluorescent layer 3.
As a method for forming the reflective thin film layer 4, vacuum thin film methods such as vapor deposition, sputtering, ion plating, and CVD (chemical vapor deposition) can be used. In particular, the CVD method causes little thermal damage to the fluorescent layer 3. Even if other thin film forming methods are used, if the thin film layer to be formed is made thin, the thermal damage can be reduced.
When this hologram sheet A is irradiated with illumination light 5 such as a fluorescent lamp, a hologram reproduction image 6 (for example, a rainbow hologram) can be visually recognized by the reflected light from the total reflection thin film layer 4.
Further, when the hologram sheet A is irradiated with light having a predetermined wavelength that causes the phosphor of the fluorescent layer 3 to emit fluorescence, for example, ultraviolet light 7 having a wavelength of 365 nm, a “red” monochromatic hologram reproduction image 8 appears in a specific direction. . (See Figure 3.)
Even if the irradiation direction of the ultraviolet ray 7 is changed, the reproduction direction of the “red” monochromatic hologram reproduction image 8 (the above-mentioned specific direction) does not change, and it can be recognized that there is a high anti-counterfeiting property. (Not shown)

Example 1
As a transparent substrate 1, a melamine resin composition is applied to the surface of a 12 μm PET film, and a relief hologram with a hologram image position detection pattern (character image of “fluorescence”: see FIG. 3) is used as a replication mold surface Was cured by heating in contact with each other to form a relief hologram, and a hologram forming layer 2 having a thickness of 3 μm was obtained.
On this hologram forming layer 2, a resin dispersed fluorescent ink having the following composition is coated by a gravure coating method and dried to form a fluorescent layer 3 having a thickness of 2.0 μm so as to be in contact with the hologram relief,
・ <Fluorescent ink composition>
UV-excited fluorescent pigment UVR-2 manufactured by Tail Navi Co., Ltd. 5 parts by mass Acrylic resin 10 parts by mass Methyl ethyl ketone 40 parts by mass Ethyl acetate 45 parts by mass On the fluorescent layer 3, from an aluminum thin film having a thickness of 200 nm, using a vacuum deposition machine manufactured by ULVAC. A total reflection thin film layer 4 was formed to produce a hologram sheet (not shown) of the present invention.
When this hologram sheet was placed under fluorescent lamp illumination light (corresponding to 5 in FIG. 3) as shown in FIG. 3, a clear hologram reproduction image (corresponding to 6 in FIG. 3) could be visually recognized.
After the fluorescent lamp was turned off, this hologram sheet was illuminated with a 365 nm wavelength light source (UV-LED module LC-L2 manufactured by Hamamatsu Photonics, which corresponds to 7 in FIG. 3). Similar to A, this ultraviolet light is not visible, and a red hologram reproduction image “fluorescence” (corresponding to 8 in FIG. 3) can be confirmed, and only the red reproduction image appears to float in space. The design was excellent.
Appropriate pressure-sensitive adhesive is applied to this hologram sheet, cut into a 3 cm square, pasted on a passport, and illuminated with a black light fluorescent tube 40 W in a dark environment (with a cover having a 3 mm diameter hole to reduce the illumination shape. ), A red hologram reproduction image could be recognized. (Not shown)

(Example 2)
Except that the resin-dispersed fluorescent ink having the following composition was coated on the hologram forming layer 2 formed in the same manner as in Example 1 by the gravure coating method and dried to form the fluorescent layer 3 with a thickness of 0.1 μm. As in Example 1,
・ <Fluorescent ink composition>
Lumilite nano RY202 (particle size 30 nm) 5 parts by mass Polyvinyl alcohol resin 10 parts by mass Isopropyl alcohol 40 parts by mass Water 45 parts by mass The hologram sheet A of the present invention was produced. (See Figure 2.)
At this time, the fluorescent layer 3 was formed with a uniform thickness following the hologram relief of the hologram forming layer 2.
When this hologram sheet A is illuminated with visible light (illumination light) 5, a very clear hologram reproduction image 6 appears. Further, the hologram sheet A is converted into a 365 nm wavelength light source 7 (UV-manufactured by Hamamatsu Photonics). When illuminated using the LED module LC-L2), this ultraviolet ray was not visible, and the red hologram reproduction image 8 “fluorescence” could be confirmed more clearly, as in Example 1. Good results were obtained. (See Figure 3.)

(Example 3)
After forming the hologram forming layer 2, a 3 μm coating film (before drying) is formed by a gravure coating method using a solvent having the following composition, and only the quick-drying component is volatilized.
・ <Solvent composition>
Cyclohexanone 1 part by mass Methyl ethyl ketone 40 parts by mass Cyclohexane 59 parts by mass Phosphor (Lumilite Nano RY202, particle size 30 nm) was sprinkled as powder (hologram forming surface 2 faced down and sprayed). ) The phosphor layer 3 is formed, further dried, the remaining solvent is volatilized, and then the transparent resin composition having the following composition is coated and dried by the gravure coating method. It is formed so as to fill the gap (at this time, the phosphor and the transparent resin provided so as to fill the gap between the phosphors are integrated into the phosphor layer 3), and the thickness of the phosphor layer 3 is 0. A hologram sheet A of the present invention was produced in the same manner as in Example 2 except that the thickness was 0.01 μm. (See Figure 2.)
・ <Transparent resin composition>
Polyvinyl alcohol resin 1 part by mass Isopropyl alcohol 49 parts by mass Water 50 parts by mass When this hologram sheet A was observed in the same manner as in Example 2, it was possible to confirm a clear hologram reproduction image 8 from Example 2. Otherwise, good results were obtained in the same manner as in Example 2. (See Figure 3.)

Example 4
Using a 12 μm high smoothness PET film (surface roughness Ra: 10 nm) as the transparent substrate 1 and using a transparent layer composition having a uniform thickness with the following composition, a uniform thickness by spin coating. A transparent layer is formed with a thickness of 2.0 μm after drying,
・ <Transparent layer composition with uniform thickness>
Melamine resin 10 parts by weight Toluene 10 parts by weight Isopropyl alcohol 10 parts by weight Methyl ethyl ketone 30 parts by weight Ethyl acetate 40 parts by weight On top of that, using the composition for the fluorescent layer having a uniform thickness, the spin coating method is used. To form a fluorescent layer having a uniform thickness with a thickness of 1.0 μm after drying,
・ <Uniform thickness composition for fluorescent layer>
UV-excited fluorescent pigment UVR-2 5 parts by mass Melamine resin 2 parts by mass Acrylic resin 3 parts by mass Isopropyl alcohol 20 parts by mass Methyl ethyl ketone 20 parts by mass Ethyl acetate 50 parts by mass A sheet having a three-layer structure of “a layer” and “a fluorescent layer having a uniform thickness” was formed. (Not shown)
The outermost surface of the “uniformly-thickness fluorescent layer” of the three-layered sheet is brought into contact with the surface of the replication mold of the relief hologram (“fluorescent” character image: see FIG. 3) used in Example 1. Relief holograms are formed using a hot roll press method at 80 ° C., 1 ton / m, and 2 m / min. “Transparent layer with uniform thickness” and “Fluorescent layer with uniform thickness” The shape of the interface with the surface and the shape of the outermost surface of the “uniformly thick fluorescent layer” are both “relief shape” of “hologram relief” (meaning substantially the same shape). Obtained the hologram sheet A of Example 4 like Example 1. FIG. By forming the relief hologram, the “transparent layer with a uniform thickness” becomes the hologram forming layer 2, and the “fluorescent layer with the uniform thickness” becomes the fluorescent layer 3. (See Figure 2.)
When this hologram sheet A was evaluated in the same manner as in Example 1, a remarkably clear hologram reproduction image 6 appeared, and furthermore, a remarkably clear red hologram reproduction image 8 “fluorescence” could be confirmed. As in Example 1, good results were obtained. (See Figure 3.)

(Comparative example)
A hologram sheet was formed without forming a fluorescent layer, and was used as a comparative example.
When observed in the same manner as in Example 1, a hologram reproduction image that can be visually recognized under a fluorescent lamp could be confirmed, but when the surroundings were darkened and irradiated with ultraviolet rays, the hologram reproduction image did not appear. It was.
From this, it was possible to determine that the hologram sheet was not genuine and the passport was fake.

A transparent sheet (hologram forming layer) having a hologram relief including a diffraction grating group corresponding to a hologram image
3 Fluorescent layer (continuous or partial formation)
4 Totally reflective thin film layer 5 Example of observation state: Visible light (illumination light)
6 Same as above: No reproduced image 7 Same as above: Ultraviolet light (illumination light)
8 Same as above: Red reproduction image

Claims (4)

A transparent resin layer having a hologram relief including a diffraction grating group corresponding to a hologram image, a fluorescent layer provided in contact with the hologram relief, and a total reflection thin film layer in this order on one surface of the transparent substrate. A hologram sheet characterized by being provided with
The hologram sheet according to claim 1, wherein the fluorescent layer is formed with a uniform thickness following the unevenness forming the hologram relief.
The hologram sheet according to claim 2, wherein the fluorescent layer has a thickness of 0.01 μm or more and 0.1 μm or less.
The hologram relief of the transparent resin layer is
A transparent layer having a uniform thickness is formed on the transparent substrate, and a fluorescent layer having a uniform thickness is formed on the transparent layer, and then the transparent layer and the fluorescent layer are simultaneously deformed. The hologram sheet according to claim 2, wherein the hologram sheet is provided by performing the steps described above.

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