JPH11209675A - Fluorescent ink and recorded information reading device - Google Patents

Abstract

(57) [Summary] [Object] It is possible to read both information recorded using invisible or inconspicuous fluorescent ink and information recorded using ordinary colored ink. The light source has an absorption wavelength of 600 to 700 nm and a wavelength of 60 nm.
A first fluorescent substance that emits fluorescence at 0 to 900 nm;
A second fluorescent substance having an absorption wavelength of 0 nm or less and emitting fluorescence at 600 to 700 nm, and producing a fluorescent ink which emits fluorescence using a wavelength in the visible light spectrum region as an excitation wavelength, and forming a bar code with the fluorescent ink; The printed label 1 is irradiated with visible light having a wavelength of 600 to 700 nm as excitation light from the LED light source 12. By passing the light from the label through a filter that cuts off the excitation light of the filter device 15, the bar code is read by causing the CCD sensor 16 to receive only the emission light of the fluorescent ink. Also, when reading a barcode printed with colored ink from a label, a filter that cuts light emitted by the fluorescent ink is used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a fluorescent ink and a recorded information reading device.

[0002]

2. Description of the Related Art For example, information such as letters, numbers, symbols, and bar codes is recorded on a recording medium using fluorescent ink which is inconspicuous under ordinary light, and the recording medium is irradiated with an appropriate excitation light. Various methods have been proposed for reading information by causing fluorescent ink to emit light.

For example, Japanese Patent Publication No. 60-29996 discloses that information recorded by a phosphor activated by neodymium ions and ytterbium ions is excited by excitation light having a wavelength of 790 to 850 nm, which excites neodymium ions. Reading information with a photodetector having a sensitivity at a wavelength of 900 to 1100 nm. Japanese Patent Application Laid-Open No. 6-500590 hardly absorbs radiation in the visible range of about 400 to 700 nm, A mark medium containing an organic dye which has good absorption of radiation near the infrared range of 750 nm, and which responds to the excitation radiation near the infrared range and fluoresces to form fluorescent radiation having a wavelength longer than the wavelength of the excitation is used. The mark is irradiated with a laser from a light source, and the fluorescence from the mark is detected by a detector through a filter. In addition, Japanese Patent Publication No. 4-64517 discloses the use of an ink composition containing a fluorescent dye that emits fluorescence other than blue-violet and blue to impart information. The recorded information is read by irradiating ultraviolet rays, and in that case, the information is passed through a filter that cuts blue-violet and blue light.

The fluorescent inks described in these publications have substantially no absorption in the visible light spectrum region, are invisible or hardly visible under ordinary light in the case of organic dyes, and white in the case of inorganic pigments. When irradiating excitation light of a certain appropriate wavelength, it emits light in the visible light region in the case of ultraviolet excitation, and emits infrared light having a wavelength longer than the wavelength of the excitation light in the case of infrared excitation. The information recorded in the fluorescent ink is read by detecting the light emitted from the fluorescent ink with a photodetector, cutting the wavelength of the excitation light source with a filter, and detecting only the emission wavelength of the fluorescent ink.

[0005]

However, such reading of information recorded using fluorescent ink which is invisible under ordinary light is almost the same as that used for technology for preventing counterfeiting of securities and cash vouchers. At present, it is not widely used, especially in barcode systems used for managing products and the like. This is because the conventional invisible fluorescent ink requires a unique excitation light source and a unique photodetector, and is compatible with the barcode system using black ink that is currently used for managing products and the like. There is no compatibility, and a barcode system using a new invisible fluorescent ink must be constructed.

JP-A-3-288894 discloses that information recorded by a phosphor activated by neodymium ions and ytterbium ions is excited by excitation light having a wavelength of 500 to 780 nm, which excites neodymium ions. It is disclosed that information is read by a photodetector having a sensitivity at a wavelength of 840 to 1100 nm. The excitation wavelength here is a range including the wavelength of 600 to 700 nm of the light source used in the current black ink barcode system, and the sensitivity range of the photodetector is also used in the current black ink barcode system. 900n sensitivity wavelength of the photodetector
m, but the fluorescent substance used in this publication is an inorganic fluorescent pigment activated by neodymium ions and ytterbium ions.
As described in JP-A-29996, originally,
Light is emitted most efficiently at an excitation wavelength of 790 to 850 nm, and emission efficiency decreases at an excitation wavelength of 500 to 780 nm. In addition, the inorganic fluorescent pigment has a very low luminous efficiency and a small amount of emitted light as compared with the organic fluorescent dye.

Further, the absorption wavelength of the inorganic fluorescent pigment activated by neodymium ions and ytterbium ions is shown in FIG.
As shown in FIG. 1, the peak wavelength is about 750 nm and 800 n.
m, and the absorption in the wavelength range of 600 to 700 nm becomes very small, so that the excitation wavelength is 600 to 70 nm.
When light having a wavelength of 0 nm is used, the amount of emitted light becomes very small.

[0008] From the above, Japanese Patent Application Laid-Open No. 3-288894 is disclosed.
For example, a barcode is recorded using a fluorescent ink containing an inorganic fluorescent pigment activated with neodymium ions and ytterbium ions described in Japanese Patent Application Publication In the case of reading using a bar code, there is a problem that a sufficient amount of emitted light cannot be obtained and a bar code cannot be read accurately.

A fluorescent ink using an organic fluorescent dye can provide a large amount of emitted light. However, if an organic fluorescent dye having an absorption in the visible light spectrum region is used, the organic fluorescent dye becomes colored. For example, an organic fluorescent dye having an absorption at a wavelength of 600 to 700 nm is used. When a dye is used, there has been a problem that a pale blue-green to blue color is applied and an invisible ink or an ink that is not conspicuous is not obtained.

According to the present invention, there is provided a fluorescent ink which is invisible or inconspicuous and which can also be used as a device for reading recorded information by using a normal colored ink for reading recorded information. I do. The invention according to claims 7 and 8 provides a recorded information reading apparatus capable of reading both information recorded using invisible or inconspicuous fluorescent ink and information recorded using ordinary colored ink.

According to the ninth and tenth aspects of the present invention, the information recorded with each ink is separated from the recording medium on which the information is recorded with both the invisible or inconspicuous fluorescent ink and the ordinary colored ink, and the information is reliably read. To provide a recorded information reading device capable of performing the above.

[0012]

According to the first aspect of the present invention,
A first fluorescent substance having an absorption wavelength in a visible light spectrum region, and a second fluorescent substance having an absorption wavelength in a region other than the visible light spectrum region and emitting light in the visible light absorption region of the first fluorescent material. And emits fluorescence with a wavelength in the visible light spectrum region as an excitation wavelength.

According to a second aspect of the present invention, in the fluorescent ink according to the first aspect, the emission wavelength region of the fluorescence is changed from a red region to a near infrared region.

According to a third aspect of the present invention, there is provided the fluorescent ink according to the second aspect, wherein the first fluorescent substance has a wavelength of 600 nm.
It has an absorption region of up to 700 nm and a wavelength of 600 to 900 n.
That is, a fluorescent substance that emits fluorescence is used for m.

According to a fourth aspect of the present invention, in the fluorescent ink of the third aspect, a fluorescent substance comprising an organic dye or an organometallic complex is used as the first fluorescent substance.

According to a fifth aspect of the present invention, in the fluorescent ink according to the third or fourth aspect, the second fluorescent substance has an absorption region having a wavelength of 400 nm or less, and has a wavelength of 600 to 700 nm.
That is, a fluorescent substance that emits fluorescence in nm is used.

According to a sixth aspect of the present invention, in the fluorescent ink of the fifth aspect, a fluorescent substance comprising an organic dye or an organometallic complex is used as the second fluorescent substance.

According to a seventh aspect of the present invention, there is provided a first fluorescent substance having an absorption wavelength in a visible light spectrum region and an absorption wavelength in a region other than the visible light spectrum region, wherein the first fluorescent substance has a visible light spectrum. A recording medium containing a second fluorescent substance that emits light in an absorption region, and recording information with a fluorescent ink that emits fluorescence with a wavelength in a visible light spectrum region as an excitation wavelength; and a unit that irradiates the recording medium with visible light. A light detecting unit that has sensitivity to the emission wavelength of the fluorescent ink and reads recorded information from the recording medium, and cuts an excitation wavelength of the fluorescent ink disposed in front of the light detecting unit when reading recorded information from the recording medium. And a recorded information reading apparatus provided with an optical filter.

According to an eighth aspect of the present invention, in the recording information reading apparatus according to the seventh aspect, the first fluorescent substance of the fluorescent ink has an absorption region at a wavelength of 600 to 700 nm and emits fluorescence at a wavelength of 600 to 900 nm. A fluorescent substance is used, and a light detecting means having sensitivity at a wavelength of 600 to 900 nm is used.

According to a ninth aspect of the present invention, there is provided a first fluorescent substance having an absorption wavelength in a visible light spectrum region and an absorption wavelength in a region other than the visible light spectrum region, wherein the first fluorescent substance has a visible light spectrum. A fluorescent ink that contains a second fluorescent substance that emits light in the absorption region and emits fluorescence with a wavelength in the visible light spectrum region as an excitation wavelength; and a colored ink that has an absorption wavelength in the visible light spectrum absorption region of the first fluorescent material. A recording medium on which information is recorded by the method, a means for irradiating the recording medium with visible light, a light detecting means having sensitivity to the emission wavelength of the fluorescent ink and reading the recorded information from the recording medium, a fluorescent ink reading mode and a colored Mode switching means for switching the ink reading mode, and when the mode switching means selects the fluorescent ink reading mode, the fluorescent ink disposed before the light detecting means is switched. A first optical filter that cuts an emission wavelength, and a second optical filter that cuts a light emission wavelength of fluorescent ink disposed in front of the light detection means when the mode switching means selects the color ink reading mode. ,
There is a recorded information reading apparatus that reads both information recorded with fluorescent ink and information recorded with colored ink.

According to a tenth aspect of the present invention, in the recording information reading apparatus of the ninth aspect, a means for irradiating visible light having a wavelength of 600 to 700 nm is used as the visible light irradiating means, and the first fluorescent light of the fluorescent ink is used. As a substance, wavelength 600-
That is, a fluorescent substance having an absorption region of 700 nm is used.

[0022]

Embodiments of the present invention will be described with reference to the drawings. (First Embodiment) A first fluorescent substance having an absorption wavelength in a visible light spectrum region and an absorption wavelength in a region other than the visible light spectrum region and having an absorption wavelength in the visible light spectrum region of the first fluorescent material. A second fluorescent substance that emits light,
A fluorescent ink that emits fluorescence using a wavelength in the visible light spectrum region as an excitation wavelength is manufactured.

When information is read from a recording medium on which information such as a barcode is recorded using colored ink, for example, black ink, a light source in a wavelength region of 600 to 700 nm is used as a light source. Therefore, as the first fluorescent substance of the fluorescent ink, a fluorescent substance which has an absorption region at a wavelength of 600 to 700 nm and emits fluorescence at a wavelength of 600 to 900 nm is used, and the second fluorescent substance has an absorption range of 400 nm or less. A fluorescent substance having an area and emitting fluorescence at a wavelength of 600 to 700 nm is used.

As a result, the first fluorescent substance has a light blue-green to blue color due to the complementary color relation. However, the first fluorescent substance contains the second fluorescent substance so that the first fluorescent substance emits light based on the principle of additive color mixing in the light shown in FIG. The ink becomes a fluorescent ink that becomes pale white in appearance and is difficult to see. That is, FIG. 2 (a) shows the reflection characteristics of the first fluorescent substance, FIG. 2 (b) shows the characteristics of the additive color mixture dye, and FIG. 2 (c) shows the reflection characteristics of this fluorescent ink. As described above, the portion where the dye having the absorption a at 600 to 700 nm is absorbed by the additive color mixture method is supplemented to obtain a fluorescent ink close to white.

As the first fluorescent substance, Nile Blue, Rh
odamine 700, Pyridine1, Pyridine2, Rhodamine
800, Oxazine 1, Oxazine 750, DTDCI, HIDCI
, Styryl 6, Styryl 8, Styryl 11, and the like. For example, an organic fluorescent dye or an organometallic complex having high luminous efficiency is usually used because a light source such as an LED which does not have a large luminous output is usually used as the light source.

As the second fluorescent substance, CaWO ₄ , Z
n ₂ SiO ₄ : Mn, Y ₂ O ₃ : Eu, Mg ₆ As ₂ O
₁₁ : An inorganic fluorescent pigment such as Mn, a coumarin, a benzoxazine derivative, an organic fluorescent dye such as a europium complex, an organic metal complex, or the like is used, and a more convenient one is selected than the first fluorescent substance. Since the second fluorescent substance also has a small amount of ultraviolet light in natural light, an organic fluorescent dye or an organic metal complex having higher luminous efficiency than an inorganic fluorescent pigment is preferable.

The fluorescent ink is printed on a base material such as paper or label by thermal transfer recording, ink jet printing, plate printing or the like to form a bar code or the like. Since the barcode formed by the fluorescent ink has an absorption in the wavelength region of the visible light spectrum, the existing black barcode information reading type light source can be used as it is, and no special light source is required.

Accordingly, as a means for irradiating a recording medium on which information such as a barcode is recorded with visible light or a light detecting means for reading information from the recording medium, the light source or detector of a current reading apparatus for reading a black barcode is used as it is. Can be used. For example, 600 to 700 n which is generally used as a light source
m red LED or semiconductor laser can be used, and a CCD sensor or a silicon diode array can be used as a detector.

As the fluorescent ink, particularly,
It is preferable to select the first fluorescent substance so as to have absorption in a wavelength region of 700 nm. Also, it is desirable to select a second fluorescent substance that emits fluorescence at a wavelength of 600 to 700 nm in accordance with the first fluorescent substance. The fluorescent ink excited by the red LED having an emission wavelength of 600 to 700 nm emits fluorescence in a wavelength region of 600 to 900 nm.

FIG. 3 is a diagram showing a main part of a recording information reading apparatus. For example, a bar code is recorded on a label 1 serving as a recording medium with a fluorescent ink which emits fluorescence using a wavelength in the visible light spectrum region as an excitation light source. I have. This fluorescent ink has a first fluorescent substance that has an absorption wavelength of 600 to 700 nm and emits fluorescence of 600 to 900 nm using the light of this wavelength as excitation light, and a first fluorescent substance that is excited by a wavelength of 400 nm or less.
It contains two kinds of fluorescent substances, that is, a second fluorescent substance that emits fluorescence of about 700 nm.

Specifically, as the first fluorescent substance, Rh
Use odamine 700, Rhodamine 800, Oxazine 750 or the like. In addition, as the second fluorescent substance, Mg ₆ A
s ₂ O ₁₁ : Mn, europium complex or the like is used. In this way, by including the second fluorescent substance that is unemployed and transparent and emits fluorescence in the absorption region of the first fluorescent substance in the thin colored first fluorescent substance, a thin white, hardly visible fluorescent ink is obtained.

In the actual production of the fluorescent ink, each fluorescent substance is subjected to ink jet, thermal transfer, offset printing,
Formulation is performed according to each printing method such as screen printing. For example, in the case of using for thermal transfer, a barcode is printed on a recording medium using a thermal transfer ink ribbon. As the ink ribbon, one obtained by applying an ink material on a base film is used.As the base film, for example, polyester,
Use plastic films such as polypropylene, cellophane, acetate, and polycarbonate, condenser paper, paraffin paper, and the like.

As the hot melt ink, a fluorescent substance, a synthetic resin, a wax and, if necessary, a solvent and an additive (dispersant,
Surfactant, etc.). Examples of the synthetic resin include ethylene-vinyl acetate copolymer (EVA), ethylene-acrylate copolymer (EEA), polyethylene, polystyrene, polypropylene, petroleum resin, vinyl chloride resin, and vinyl chloride-vinyl acetate copolymer. Use is made of coalesce, polyvinyl alcohol, vinylidene chloride resin, methacrylic resin, polyamide, polycarbonate, fluororesin, polyvinyl formal, polyvinyl butyral, acetyl cellulose, nitrocellulose, polyvinyl acetate, polyisobutylene, ethyl cellulose, polyurethane, polyacetal, and the like. Examples of the wax include, for example, carnauba wax, paraffin wax, microcrystalline wax, beeswax, whale wax, Ibota wax, wool wax, shellac wax, montan wax,
Use candy wax, petrolactam or the like. When a solvent is required, for example, benzene, xylene, toluene, trichlene, ethyl acetate, methanol,
Ethanol, isopropanol, methyl ethyl ketone,
Use cyclohexane or the like.

As an example, Rhodamine is used as the first fluorescent substance.
700, using a europium complex as the second fluorescent substance,
On a base film consisting of a polyester film having a thickness of 6 μm, the ink thickness is about 4 μm by a hot melt coating method.
To produce a thermal transfer ink ribbon. in this case,
The fluorescent substance is a wax-like substance solid solution or a resin solid solution obtained by imparting wax-like or resin-like properties to the fluorescent dye so that thermal transferability does not decrease.

Examples of the wax-like solid solution include stearic acid monoethanolamide, lauric acid monoethanolamide, coconut oil fatty acid monoethanolamide, sorbitan behenic acid ester, glycerin monostearic acid ester, acetylsorbit, benzoylsorbitol, and acetylmannitol. Use etc. Examples of the resin solid solution include polycaprolactone having an average molecular weight of 10,000, polyethylene glycol having an average molecular weight of 6,000, low condensation polymerization melamine / toluenesulfonamide resin, low condensation polymerization benzyltoluenesulfonamide resin, acrylic resin, and linear polyamide resin. use.

As a method for producing a solid solution, there are a bulk resin pulverization method, an emulsion polymerization method, a resin precipitation method and the like. The bulk resin pulverization method is a method in which a resin and a fluorescent dye are melt-mixed and then solidified by cooling, and the obtained lump is pulverized.The emulsion polymerization method is to add a resin powder obtained by emulsion polymerization to a hot aqueous solution of a fluorescent dye to convert the dye into a resin. was sucked into the powder, a method for further filtration and drying it, also, the resin deposition is Al ₂ (sO ₄₎ the aqueous solution of water-soluble salts and fluorescent dyes of the resin ₃ · 8H ₂ water soluble, such as O This is a method in which an aqueous solution of a metal salt is added to cause a reaction, and if necessary, the solution is acidified to precipitate the dissolved resin as a metal salt while adhering to the fluorescent dye, followed by filtration and drying.

In the solid solution thus obtained, the luminescence intensity increases as the concentration of the tendency dye increases. However, when the concentration exceeds a certain concentration, concentration quenching occurs and the luminescence intensity decreases. At a certain density or less, information cannot be read. For this reason, the ratio of the fluorescent dye in the solid solution is 0.01 to 5.0, respectively.
A suitable amount is about weight%.

Here, the production of a resin solid solution of a fluorescent dye by the bulk resin pulverization method will be described. Chain polyamide resin 98.95% by weight Rhodamine 700 0.05% by weight Europium complex 1.00% by weight First, a chain polyamide resin is heated and melted at 125 ° C, and when it becomes transparent, the temperature is raised to 170 ° C to 180 ° C. increase.
Subsequently, Rhodamine 700 and a europium complex are added thereto, melted, cooled, solidified, and then pulverized to produce a resin solid solution. Although a chain polyamide resin was used as the resin, it is a matter of course that the present invention is not limited to this.

A thermal transfer ink ribbon is prepared using the resin solid solution thus manufactured. That is, resin solid solution 20% by weight paraffin wax 70% by weight ethylene-vinyl acetate copolymer 10% by weight These resin solid solution, paraffin wax and ethylene-
After the vinyl acetate copolymer is melted and expanded, the ink is formed to a thickness of about 4 μm on a base film made of a polyester film having a thickness of 6 μm by a hot melt coating method to prepare a thermal transfer ink ribbon.

The barcode 2 is printed on the label 1 by a thermal printer using the thus-prepared thermal transfer ink ribbon as shown in FIG. Character information 3 is already printed on the label 1 using colored ink.
Rhodamine 700 has an absorption region at a wavelength of 600 to 700 nm as shown in the absorption spectrum of FIG. By mixing the europium complex, a thin white fluorescent ink is obtained. The europium complex has an absorption spectrum g2 at a wavelength of 400 nm or less as shown by a dotted line in FIG. For this reason, even if the barcode 2 is printed on the character information 3, the character information 3 is not concealed, and the appearance does not seem strange.

The label 1 on which the bar code 2 is printed on the character information 3 in this manner is transmitted from the LED light source 12 of the hand-held recording information reading device 11 to wavelengths 600 to 7.
A visible light of 00 nm is irradiated as excitation light. The light from the label 1 is passed through a condenser lens 13, a reflection mirror 14, and a filter device 15 to a wavelength of 600 to
C with sensitivity at 700 nm and peak wavelength of 630 nm
It is input to the CD sensor 16. Then, after the output of the CCD sensor 16 is amplified by the amplifier circuit 17, the output is supplied to the subsequent recognition unit.

The filter device 15 has a structure in which a first filter 18 and a second filter 19 are arranged on the left and right as shown in FIG. 4, and the first filter 18 is indicated by g3 in FIG. The second filter 19 has optical characteristics and cuts a wavelength of 670 nm or less including excitation light of the fluorescent ink. The second filter 19 has an optical characteristic indicated by g4 in FIG. It is.
Note that g5 in FIG. 9 indicates the emission characteristics of the fluorescent ink, and g6 in FIG. 9 indicates the excitation characteristics of the fluorescent ink.

The filter device 15 is operated by a mode changeover switch 20 as a mode changeover means.
The position of the first filter 18 or the position of the second filter 19 is switched before 6. Therefore, as shown in FIG.
When the barcode 2 is read from the label 1 on which is printed, the changeover switch 20 is operated so that the first filter 18 is arranged in front of the CCD sensor 16.

When the label 1 is irradiated with the excitation light from the LED light source 12 in this state, the excitation light is
The character information 3 and the blank part of the label are respectively irradiated. Since the barcode 2 is printed with fluorescent ink, the barcode 2 emits light emitted from the fluorescent ink. Further, since the character information 3 is printed with colored ink, light is almost absorbed. Further, in the blank portion, light is reflected according to the reflectance of the label 1 paper.

Thus, the reflected light of the excitation light and the light emitted from the fluorescent ink are emitted from the label 1. This light is incident on the first filter 18 via the condenser lens 14 and the reflection mirror 13, but the reflected light of the excitation light is cut by the first filter 18, so that only the light emitted from the fluorescent ink is emitted. Pass through the first filter 18 and enter the CCD sensor 16.

Thus, the bar code 2 printed with the fluorescent ink from the label 1 can be reliably read. As shown in FIG. 6, when reading the bar code 22 from the label 23 on which the character information 21 and the bar code 22 are printed with the color ink, the second filter 19 is switched so as to be arranged in front of the CCD sensor 16. The switch 20 is operated.

In this state, when the light from the LED light source 12 irradiates the bar code 22 of the label 23, this light irradiates the bar and the blank portion of the bar code 22, respectively. Since the barcode 22 is printed with colored ink, light is almost absorbed. In the blank portion, light is reflected according to the reflectance of the label 23 on the paper. Thus, the reflected light from the label 23 is incident on the second filter 19 via the condenser lens 14 and the reflection mirror 13. Since the second filter 19 allows this reflected light to pass, the CCD sensor 16 can reliably read the barcode 22 printed on the label 23.

In this case, even if there is information such as a bar code printed with fluorescent ink near the bar code 22, the light emitted from the fluorescent ink is cut by the second filter 19, so The emitted light can be prevented from becoming disturbance noise, and even in such a case, the barcode 22 printed with colored ink can be reliably read.

As described above, a reading apparatus using the LED light source 12 and the CCD sensor 16 and capable of reading a normal label 23 on which a barcode 22 is printed with colored ink is provided.
A bar code 22 printed with colored ink is obtained only by disposing the filter device 15 composed of various types of filters 18 and 19.
The bar code 2 printed with the fluorescent ink can also be read. That is, a dedicated reading device for reading a barcode printed with fluorescent ink can be dispensed with.

Although the fluorescent ink absorbs light at 600 to 700 nm, it is an inconspicuous ink due to whitening due to additive color mixing, so that it is possible to read character information and barcodes printed with colored ink by fluorescent ink printing. There is no adverse effect. Therefore, the fluorescent ink barcode can be printed in the vicinity of or superimposed on the character information or barcode printed with the colored ink, and the label paper can be used effectively without waste.

(Second Embodiment) The first embodiment described above
The same parts as those of the first embodiment are denoted by the same reference numerals, and different parts will be described. The hand-held type recorded information reading device 31 shown in FIG.
Visible light of about 700 nm is emitted as excitation light onto the label 1 via the collimator lens 32 and the galvanometer mechanism 33. That is, after the excitation light from the LED light source 12 is shaped into a substantially parallel beam by the collimator lens 32, it is reflected on the reflecting surface of the galvano mechanism 33, and the barcode 2 of the label 1 is scanned by the galvano mechanism 33. Is converted to a beam.

The light from the label 1 is incident on the CCD sensor 16 via the condenser lens 14 and the filter device 15. The filter device 15 includes two types of filters 1 by a driving mechanism (not shown) such as a motor.
The configuration is such that the filters 8 and 19 are switched, and it is possible to switch between disposing the filter 18 and the filter 19 in front of the CCD sensor 16 by operating the mode switching switch 20.

In such a configuration, the barcode 2 is printed from the label 1 on which the barcode 2 is printed with the fluorescent ink.
When reading the image data, the mode changeover switch 20 is operated to change the filter 18 of the filter device 15 to the CCD sensor 16.
Place in front of. When the excitation light is emitted from the LED light source 12 in this state, the excitation light is converted into a substantially parallel beam by the collimator lens 32, and is further converted into a beam for scanning the label 1 by the galvanometer mechanism 33.

Thus, the bar code 2 on the label 1 is scanned by the excitation light. On the label 1, the fluorescent ink of the barcode 2 is excited by the excitation light to emit light, and the emitted light is emitted. Further, the character information on the label 1 absorbs the excitation light, and the blank portion reflects the excitation light. Thus label 1
Then, the light emitted from the fluorescent ink and the reflected light of the excitation light are emitted, and are incident on the filter 18 via the condenser lens 14. The filter 18 cuts off the reflected light of the excitation light and passes only the light emitted from the fluorescent ink. Thus, only light emitted from the fluorescent ink enters the CCD sensor 16 and
The CD sensor 16 can reliably read the barcode 2.

When the bar code 22 is read from a normal label 23 on which the bar code 22 is printed together with the character information 21 using colored ink, the mode switch 20 is used.
To place the filter 19 of the filter device 15 in front of the CCD sensor 16. In this state, the LED light source 12
Is emitted by the collimator lens 32, the light becomes a substantially parallel beam, and is further converted by the galvanometer mechanism 33 into a beam that scans the label 1.

Thus, the bar code 22 on the label 23
Are scanned by the light beam. On the label 23, the bar of the bar code 23 absorbs light, and the blank portion reflects light.
Thus, the reflected light of the irradiation light is emitted from the label 23 and is incident on the filter 19 via the condenser lens 14. Since the filter 19 transmits this reflected light, the reflected light is CC
The light enters the D sensor 16. Thus, the CCD sensor 16
Can reliably read the barcode 22 from the label 23.

Therefore, in this embodiment, the LED
The light source 12 and the CCD sensor 16 are used, and only the filter 34 is arranged in a reading device that can read a normal label 23 on which the barcode 22 is printed with colored ink.
Both the barcode 22 printed with colored ink and the barcode 2 printed with fluorescent ink can be read. That is,
A dedicated reader for reading a barcode printed with fluorescent ink can be dispensed with.

The printing of the fluorescent ink does not adversely affect the reading of character information or bar codes printed with the colored ink. Therefore, the fluorescent ink barcode can be printed in the vicinity of or superimposed on the character information or barcode printed with the colored ink, and the label paper can be used effectively without waste.

In each of the above-described embodiments, the case where two types of filters, that is, a filter for cutting the excitation light from the light source and a filter for cutting the emission light of the fluorescent ink are used, is not necessarily limited to this. Instead, when printing the barcode of the fluorescent ink in an area different from the character information as in the case of the normal label 23, the filter for cutting the emission light of the fluorescent ink can be omitted.

In each of the above-described embodiments, an LED light source is used as a means for irradiating a label with visible light, and a CCD sensor is used as a light detecting means for reading a bar code. However, the present invention is not limited to this. Of course. For example, 630nm, 660n instead of LED light source
A semiconductor laser that emits a laser having a wavelength of m or 670 nm may be used as the light source. Further, the reading device is not limited to the handy type. Furthermore, if a fluorescent ink excited at a wavelength in the same region as the absorption wavelength of the colored ink is used as the fluorescent ink, whitening by additive color mixing may not be performed.

[0061]

According to the first to sixth aspects of the present invention, an invisible or inconspicuous information reading apparatus can also be used as an apparatus for reading information recorded using ordinary colored ink for reading recorded information. A fluorescent ink can be provided.
According to the seventh and eighth aspects of the present invention, there is provided a recording information reading apparatus capable of reading information recorded using fluorescent ink which is invisible or inconspicuous, and information recorded using ordinary colored ink. it can.

According to the ninth and tenth aspects of the present invention, the information recorded with the respective inks is separated from the recording medium on which the information is recorded with both the invisible or inconspicuous fluorescent ink and the ordinary colored ink, thereby ensuring the separation. And a recording information reading apparatus that can read the information.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining the principle of additive color mixing in light.

FIG. 2 is a diagram for explaining the spectral principle of fluorescent ink using an additive color mixture method in light.

FIG. 3 is a schematic configuration diagram of a main part of the first embodiment of the present invention.

FIG. 4 is a diagram showing a configuration of a filter according to the embodiment.

FIG. 5 is a diagram showing an example of a label on which a barcode is printed with fluorescent ink used in the embodiment.

FIG. 6 is a view showing an example of a normal label on which a barcode is printed with colored ink used in the embodiment.

FIG. 7 shows a first fluorescent substance used in the embodiment.
The figure which shows the absorption spectrum of Rhodamine 700.

FIG. 8 shows an absorption spectrum and an emission spectrum of a europium complex which is a second fluorescent substance used in the embodiment.

FIG. 9 is a view showing optical characteristics of a filter used in the embodiment and emission characteristics and excitation characteristics of a fluorescent ink.

FIG. 10 is a schematic configuration diagram of a main part of a second embodiment of the present invention.

FIG. 11 is a diagram showing an absorption spectrum of an inorganic fluorescent pigment used in a conventional fluorescent ink.

[Explanation of symbols]

 1, 23 ... label 11 ... record information reading device 12 ... LED light source 15 ... filter device 16 ... CCD sensor 20 ... mode changeover switch

Claims (10)

[Claims] 1. A first fluorescent substance having an absorption wavelength in a visible light spectrum region, and having an absorption wavelength in a region other than the visible light spectrum region and emitting light in an absorption region of the visible light spectrum of the first fluorescent material. A fluorescent ink containing a second fluorescent substance and emitting fluorescence with a wavelength in a visible light spectrum region as an excitation wavelength. 2. The fluorescent ink according to claim 1, wherein the emission wavelength region of the fluorescence is a region from red to near infrared. 3. The method according to claim 1, wherein the first fluorescent material has a wavelength of 600 to 700.
3. The fluorescent ink according to claim 2, which has an absorption region of nm and emits fluorescence at a wavelength of 600 to 900 nm. 4. The fluorescent ink according to claim 3, wherein the first fluorescent substance comprises an organic dye or an organic metal complex. 5. The fluorescent ink according to claim 3, wherein the second fluorescent substance has an absorption region having a wavelength of 400 nm or less and emits fluorescence at a wavelength of 600 to 700 nm. 6. The fluorescent ink according to claim 5, wherein the second fluorescent substance comprises an organic dye or an organometallic complex. 7. A first fluorescent substance having an absorption wavelength in a visible light spectrum region, and having an absorption wavelength in a region other than the visible light spectrum region, and emitting light in an absorption region of the visible light spectrum of the first fluorescent material. A recording medium containing a second fluorescent substance and recording information with a fluorescent ink that emits fluorescence with a wavelength in the visible light spectrum region as an excitation wavelength; a means for irradiating the recording medium with visible light; A light detecting unit that has sensitivity to an emission wavelength and reads recorded information from the recording medium, and cuts an excitation wavelength of the fluorescent ink disposed in front of the light detecting unit when reading recorded information from the recording medium. A recorded information reading device comprising an optical filter. 8. The first fluorescent substance of the fluorescent ink has a wavelength of 6
It has an absorption range of 00 to 700 nm and a wavelength of 600 to 90
8. The recording information reading apparatus according to claim 7, wherein the recording information reading apparatus is a substance that emits fluorescence at 0 nm, and the light detection unit has sensitivity at a wavelength of 600 to 900 nm. 9. A first fluorescent substance having an absorption wavelength in a visible light spectrum region, and having an absorption wavelength in a region other than the visible light spectrum region, and emitting light in an absorption region of the visible light spectrum of the first fluorescent material. Information is recorded by a fluorescent ink containing a second fluorescent substance and emitting fluorescence with a wavelength in a visible light spectrum region as an excitation wavelength and a colored ink having an absorption wavelength in an absorption region of the visible light spectrum of the first fluorescent substance. Recording medium, means for irradiating the recording medium with visible light, light detecting means having sensitivity to the emission wavelength of the fluorescent ink, and reading recorded information from the recording medium, a fluorescent ink reading mode and a colored ink reading mode. Mode switching means for switching modes, and the fluorescent ink disposed before the light detecting means when the mode switching means selects the fluorescent ink reading mode. A first optical filter for cutting the excitation wavelength of the light, and a second optical filter for cutting the emission wavelength of the fluorescent ink disposed in front of the light detection means when the mode switching means selects the color ink reading mode. A recording information reading device provided with a filter for reading both information recorded with the fluorescent ink and information recorded with the colored ink. 10. The visible light irradiation means has a wavelength of 600 to 70.
10. The recording information reading apparatus according to claim 9, wherein the recording information reading apparatus emits 0 nm visible light, and the first fluorescent substance of the fluorescent ink has an absorption region having a wavelength of 600 to 700 nm.