JP2013208774A - Information recording medium and postcard - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an information recording medium or the like in which even when written information is protected, the written information can be easily read.SOLUTION: In an information recording medium 1, an infrared fluorescence layer 13 including a phosphor excited by excitation light caused by infrared light and emitting the infrared light having a different peak wavelength from that of the excitation light is provided on a base material 11. The infrared fluorescence layer 13 includes a material absorbing an infrared absorption material 15 and enable writing by the infrared absorption material 15. In the information recording medium 1, the written information is covered with an infrared transmitting/visible light reflecting/absorbing layer 17, so that the written information is invisible and protected, meanwhile, irradiation with the excitation light caused by the infrared light enables the written information to be read even when the infrared transmitting/visible light reflecting/absorbing layer 17 is not removed.

Description

  The present invention relates to an information recording medium using an infrared fluorescent layer, and a postcard using the information recording medium.

  As a technology for protecting information formed on a medium, an example is disclosed in which image information is printed with ink that absorbs infrared light, and a layer that emits infrared light by being excited by infrared light is provided on the image information, and this image information is concealed. It is shown in Document 1 and Patent Document 2. Although this image information is not visible to the naked eye, it can be read by infrared rays.

  However, the information to be protected is not limited to information formed in advance by printing. For example, there are cases where writing is performed using a writing instrument or the like. As an example of this, there may be a case where personal information or the like is entered in a questionnaire or the like using a postcard.

  Conventionally, a postcard provided with an information protection seal is known as a means for protecting such information. This postcard is used when conducting a questionnaire or the like, and the respondent puts an information protection sticker in order to make the written personal information invisible, and is collected by the company or the like who conducted the questionnaire. An example of this type of postcard is shown in Patent Document 3.

Utility Model Registration No. 3013328 JP 2001-96889 A JP 2011-110891 A

However, this type of conventional postcard has a problem that it is necessary to remove the protective seal when the questionnaire collector checks the information, and the work of removing the seal becomes a burden.
In particular, when it is necessary to confirm a large amount of information through a questionnaire or the like, it is desirable to reduce the time and effort required for confirmation.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide an information recording medium that can be easily read even when written information is protected.

  The first invention for achieving the above-described object is to provide a phosphor that emits infrared light having a peak wavelength different from that of excitation light, and a material that absorbs an infrared absorbing material, on a base material. The information recording medium is provided with an infrared fluorescent layer.

  When the information recording medium of the first invention is irradiated with excitation light by infrared rays, the infrared fluorescent layer emits infrared rays, while the information written by the infrared absorbing material absorbs infrared rays. Therefore, if the information recording medium is imaged by receiving infrared rays, the written information can be easily read due to the difference in the amount of infrared rays. For example, this information may be extracted by image processing or the like, or a captured image may be displayed on a monitor for confirmation. If the written information is protected by a material that transmits infrared rays, reading of the infrared rays is not hindered.

According to a second aspect of the present invention, an infrared fluorescent layer including a phosphor that emits an infrared ray that is excited by infrared excitation light and has a peak wavelength different from that of the excitation light is provided on a base material, and an infrared ray is provided on the infrared fluorescent layer. An information recording medium comprising a material that absorbs an absorbing material and provided with a layer that transmits infrared rays.
According to the second invention, the same effect as the first invention can be obtained. Furthermore, in the second invention, a layer is further provided on the infrared fluorescent layer, whereby the infrared fluorescent layer can be protected. On the other hand, in the first invention, since there is only one layer on the substrate, the information recording medium can be made thin.

The material that absorbs the infrared absorbing material is preferably a porous material.
Thereby, an infrared absorber is absorbed suitably and favorable writing property is obtained.

It is desirable that a layer that transmits infrared light and reflects or absorbs visible light is provided so as to cover the infrared fluorescent layer.
In this way, the information written on the infrared fluorescent layer of the information recording medium can be easily made invisible by covering it with a layer that transmits infrared light and reflects or absorbs visible light. Moreover, the written information can be read without peeling off this layer.

In addition, it is desirable that a layer that transmits infrared light and reflects or absorbs visible light is provided so as to be separable.
This makes it possible to separate the layers as necessary, for example, when it is desired to visually confirm the written contents.

  According to a third aspect of the present invention, a postcard paper is provided with a phosphor that emits infrared light that is excited by infrared excitation light and has a peak wavelength different from that of the excitation light, and an infrared phosphor layer that includes a material that absorbs an infrared absorber. It is a postcard characterized by that.

  According to the postcard of the third invention, information written with the infrared absorbing material can be easily read by infrared rays. Therefore, unlike the conventional postcard with an information protection seal, there is no need to remove the information protection seal in order to confirm written information, and the burden can be reduced. If the written information is protected by a material that transmits infrared rays, reading of the infrared rays is not hindered.

According to a fourth aspect of the present invention, an infrared fluorescent layer including a phosphor that emits infrared light that is excited by infrared excitation light and has a peak wavelength different from that of the excitation light is provided on the postcard paper, and infrared absorption is performed on the infrared fluorescent layer. The postcard is characterized in that it includes a material that absorbs the material and is provided with a layer that transmits infrared rays.
According to the fourth invention, the same effect as the third invention can be obtained. Furthermore, in the fourth invention, an additional layer is provided on the infrared fluorescent layer, whereby the infrared fluorescent layer can be protected. On the other hand, in the third invention, since there is only one layer on the postcard, the postcard can be made thin.

  According to the present invention, it is possible to provide an information recording medium or the like that can be easily read even when written information is protected.

The figure shown about the information recording medium 1 The figure shown about the readers 50 and 58 The figure which shows the image data 90 The figure shown about the information recording medium 1a Illustration showing postcard 60 Diagram showing writing on postcard 60 and protection of written information Illustration showing postcard 70

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[First Embodiment]
(Configuration of information recording medium)
FIG. 1 is a diagram showing an information recording medium 1 according to the first embodiment of the present invention. As shown in FIG. 1A, in the information recording medium 1, an infrared fluorescent layer 13 is provided on a base material 11.

  The base material 11 is, for example, various paper materials such as postcards, but other materials such as plastic are not particularly limited.

  The infrared fluorescent layer 13 is provided by solid-printing a fluorescent material containing a phosphor that emits infrared light having a peak wavelength different from that of the excitation light. Solid printing may be performed by offset printing, gravure printing, flexographic printing, screen printing, pad printing, or the like. Further, the infrared fluorescent layer 13 may be formed on the substrate 11 using a transfer sheet, a label, or the like. Further, the infrared fluorescent layer 13 may be formed by spray coating the fluorescent material.

  In the present embodiment, the infrared fluorescent layer 13 further includes a material that absorbs an infrared absorbing material 15 described later. This is, for example, a porous inorganic material such as silica, which can improve the writing property of the infrared fluorescent layer 13 and can serve as a sign panel for writing. Such effects are also described in JP-A-9-319307.

  The material that absorbs the infrared absorbing material 15 is not limited to silica, and other materials such as clay, talc, calcium carbonate, barium sulfate, titanium oxide, alumina, and kaolin can also be used. Further, a porous resin or the like may be used.

FIG. 1B is a diagram illustrating a state where writing is performed on the infrared fluorescent layer 13 using the infrared absorbing material 15.
The infrared absorbing material 15 is a material that absorbs infrared rays, and examples of writing instruments using the infrared absorbing material 15 include general pencils, water-based ballpoint pens, oil-based ballpoint pens, water-based signpoint pens, and oil-based signpoint pens.

  FIG. 1C is a diagram showing a state in which an infrared transmission / visible light reflection / absorption layer 17 is provided so as to cover the infrared fluorescent layer 13 on which writing is performed by the infrared absorbing material 15.

The infrared transmitting / visible light reflecting / absorbing layer 17 is a layer that transmits infrared light and reflects or absorbs visible light, and a paper material or the like can be used. However, the present invention is not limited to this, and any material that transmits infrared light and reflects or absorbs visible light can be used.
The infrared transmission / visible light reflection / absorption layer 17 is provided with an adhesive layer on one surface, and is pasted so as to cover written information. However, the present invention is not limited to this, and an infrared transmission / visible light reflection / absorption layer 17 may be used as an envelope, and the information recording medium 1 may be enclosed therein.

  As described above, in the information recording medium 1, information written on the infrared fluorescent layer 13 by the infrared absorbing material 15 becomes invisible by applying the infrared transmitting / visible light reflecting / absorbing layer 17. However, by irradiating the information recording medium 1 with infrared rays, this information can be read without removing the infrared transmission / visible light reflection / absorption layer 17. Hereinafter, reading using infrared rays will be described.

(Reading of the information recording medium 1)
Next, reading of the information recording medium 1 shown in FIG. 1C will be described with reference to FIG.
FIG. 2 is a diagram showing configuration examples 50 and 58 of a reading device for reading information written with the infrared absorbing material 15 on the infrared fluorescent layer 13 of the information recording medium 1.

  As shown in FIG. 2A, the reading device 50 includes an infrared irradiation device 51, an infrared camera 55, a filter 53, and the like.

The infrared irradiation device 51 is, for example, a light emitting diode or the like, and irradiates the information recording medium 1 with infrared rays as excitation light.
The infrared camera 55 is an infrared imaging device that receives infrared light emitted from the phosphor of the infrared fluorescent layer 13 excited by excitation light with a light receiving element, and converts the amount of light received by each light receiving element into a luminance value on an image. is there. The infrared camera 55 is not particularly limited as long as it has sensitivity in the infrared region.
The filter 53 is provided on the light receiving surface of the infrared camera 55, and cuts infrared rays irradiated as excitation light from the infrared irradiation device 51. As a result, the infrared camera 55 receives only the infrared light emitted from the infrared fluorescent layer 13.

As the excitation light, for example, infrared light having a peak wavelength of 750 to 900 nm is used, and the infrared fluorescent layer 13 is a fluorescent material that is excited by the excitation light and has an infrared peak wavelength of 901 to 1100 nm emitted by the excitation. Is used. An example of such a material is SG-YS manufactured by Nemoto Special Chemical Co., Ltd.
As the filter 53, for example, by using a filter that transmits only infrared rays having a wavelength of 901 nm or more, the excitation light from the infrared irradiation device 51 is cut, and only infrared rays emitted from the infrared fluorescent layer 13 are received by the infrared camera 55 and imaged. It can be performed.

  The infrared fluorescent layer 13 is not limited to the above, and known fluorescent materials having different peak wavelengths of excitation light and infrared light emitted by excitation may be used as appropriate. The filter 53 is not limited to the above, and a known filter that cuts the peak wavelength of the excitation light and transmits the peak wavelength of infrared light emitted by excitation may be used as appropriate.

  The information processing device 57 includes a control unit including a CPU (Central Processing Unit), a RAM (Random Access Memory), a ROM (Read Only Memory), a display unit, a storage unit, an input / output unit of a peripheral device, and the like. An image acquired from the infrared camera 55 is displayed on a display unit, or written information is extracted as data using image processing software stored in a storage unit.

  The example in FIG. 2A is a separation type in which the reading device 50 is connected to an external information processing device 57. This reading device is shown in the reading device 58 in FIG. 2B. As described above, the information processing device 57 may be an integrated type in which the information processing device 57 is incorporated. The other configuration of the reading device 58 is the same as that shown in FIG.

  When reading information written with the infrared absorbing material 15, first, the information recording medium 1 is irradiated with excitation light from the infrared irradiation device 51 of the reading device 50. Excitation light passes through the infrared transmission / visible light reflection / absorption layer 17 and excites the phosphor of the infrared fluorescent layer 13. The excited phosphor emits infrared light having a peak wavelength different from that of the excitation light. This infrared light passes through the infrared transmission / visible light reflection / absorption layer 17 and is received by the infrared camera 55 through the filter 53. The image data captured in this way is input to the information processing device 57, where the image data is displayed and written information is extracted.

  FIG. 3 is an example of image data 90 captured by the infrared camera 55. By irradiating the excitation light, the infrared fluorescent layer 13 emits infrared light, and thus appears as a high-luminance part on the image data 90 except for the writing part by the infrared absorbing material 15. On the other hand, since the writing portion by the infrared absorbing material 15 absorbs excitation light, it appears on the image data 90 with a strong contrast as a portion having a lower luminance than the surrounding infrared fluorescent layer 13.

  Due to the brightness difference between the two parts and the clarity of the outline of the writing part, information written by the infrared absorber 15 in the image data 90 can be easily read. It is convenient for reading information that the infrared fluorescent layer 13 functions as a backlight and the entire image data becomes bright. It should be noted that the base material 11 appears on the image data 90 as a low-brightness part in a part that is off the infrared fluorescent layer 13. This is because the excitation light reflected from the substrate 11 is cut by the filter 53.

  Thus, according to the first embodiment, when the information recording medium 1 is irradiated with infrared excitation light, the infrared fluorescent layer 13 emits infrared light, while the information written in the infrared absorber 15 transmits infrared light. Absorb. Therefore, if the information recording medium 1 is imaged by receiving infrared rays, the written information can be easily read due to the difference in the amount of infrared rays. For example, this information may be extracted as data by image processing or the like, or a captured image may be displayed on a monitor for confirmation.

Further, since the infrared transmitting / visible light reflecting / absorbing layer 17 is provided so as to cover the infrared fluorescent layer 13, the information written in the infrared absorbing material 15 can be made invisible and peeled off when the information is read. There is no need.
If the adhesive layer of the infrared transmission / visible light reflection / absorption layer 17 can be peeled off, the infrared transmission / visible light reflection / absorption layer 17 is peeled off and separated later, and the written contents are visually checked if necessary. You can also check it. In the case where the envelope is the infrared transmission / visible light reflection / absorption layer 17 as described above, the information recording medium 1 can be taken out of the envelope and separated.

  In addition, the information recording medium 1 of the present embodiment includes the infrared fluorescent layer 13 on the base material 11 containing a material that absorbs the infrared absorbing material 15. Instead, the information recording medium shown in FIG. As shown in the medium 1 a, an infrared fluorescent layer 13 a may be provided on the substrate 11, and a layer 18 containing a material that transmits infrared rays and absorbs the infrared absorbing material 15 may be further provided thereon.

  In this case, the infrared fluorescent layer 13a does not include a material that absorbs the infrared absorbing material 15 as described above. The infrared absorbing material 15 is placed on the upper layer 18 in, for example, a synthetic resin that transmits infrared rays. It is assumed that the material to be absorbed is dispersed and included. As a material that absorbs the infrared absorbing material 15, for example, a porous inorganic material such as silica can be used as described above.

  This information recording medium 1a can provide the same effects as the information recording medium 1 of the first embodiment. Furthermore, since the layer 18 is provided on the infrared fluorescent layer 13a, the infrared fluorescent layer 13a can be protected thereby. On the other hand, the information recording medium 1 of the first embodiment has an advantage that the medium can be made thin because there is only one layer on the substrate 11.

  The information recording medium of the present invention exemplified in the first embodiment can easily be read with infrared rays while making written information invisible, and can be used for various applications. One of them is a postcard with an information protection seal. Hereinafter, this example will be described as second and third embodiments.

[Second Embodiment]
FIG. 5 is a diagram showing a postcard 60 which is an information recording medium according to the second embodiment of the present invention. FIG. 5A is a diagram showing a plane of the postcard 60, and FIG. 5B is a diagram showing a cross section along the line AA in FIG. 5A. FIG. 6 is a diagram showing writing on the postcard 60 and protection of the written information.

  As shown in FIG. 5A, an infrared ray transmitting / visible light reflecting / absorbing layer 17 is provided on the back surface of the postcard 60 as an information protection seal. The infrared transmission / visible light reflection / absorption layer 17 is attached to the postcard with an adhesive layer on which the infrared transmission / visible light reflection / absorption layer 17 can be peeled off and reattached. The light reflection / absorption layer 17 can be separated. Thus, after the infrared transmission / visible light reflection / absorption layer 17 is peeled off and information is written by writing, it can be attached again to protect the information.

  As shown in FIG. 5B, in the postcard 60, a writable infrared fluorescent layer 13 similar to the above is provided on a predetermined writing field of the base material 11 which is a postcard paper so as to cover it. In addition, the infrared transmission / visible light reflection / absorption layer 17 is attached.

  As shown in FIG. 6A, the user once peels off the infrared transmission / visible light reflection / absorption layer 17 of the postcard 60 and performs writing with the infrared absorbing material 15 on the infrared fluorescent layer 13 in the writing column. After that, as shown in FIG. 6B, the infrared transmission / visible light reflection / absorption layer 17 is pasted again from the written information.

  Similarly to the information recording medium 1 of the first embodiment, the postcard 60 can be used to easily write written information without peeling off the infrared transmission / visible light reflection / absorption layer 17 by the reading device 50 shown in FIG. Can be read. The read information can be displayed on a monitor for confirmation or extracted as data by image processing, and the same effect as in the first embodiment can be obtained.

  Thereby, unlike the conventional postcard with an information protection seal, there is no need to remove the information protection seal in order to confirm the information of the collected postcard, and the burden can be reduced. In addition, there is an advantage that the postcard after the information protection seal is peeled off is not bulky and can be stored easily. In addition, since the infrared transmission / visible light reflection / absorption layer 17 is separable, it can be separated as necessary, and the written content can be confirmed visually.

[Third Embodiment]
FIG. 7 is a diagram showing a postcard 70 which is an information recording medium according to the third embodiment of the present invention. FIG. 7A is a view showing a plane of the postcard 70, and FIG. 7B is a view showing a cross section taken along line BB in FIG. 7A. FIG. 7C is a diagram showing the enclosing of the postcard 70 in the envelope 80.

  As shown in FIGS. 7A and 7B, on the back surface of the postcard 70, a writable infrared fluorescent layer 13 similar to the above is written on a predetermined writing field of the base material 11 which is a postcard paper. Is provided.

  As shown in FIG. 7 (c), this postcard 70 includes an information protection seal 90 in which the infrared transmission / visible light reflection / absorption layer 17 is adhered to a substrate (not shown) with an adhesive layer that can be peeled off and reattached. At the same time, it is enclosed in an envelope 80 and mailed to the user.

  The user performs writing with the infrared absorbing material 15 on the infrared fluorescent layer 13 in the writing column, as in the second embodiment. Then, the infrared transmission / visible light reflection / absorption layer 17 of the information protection seal 90 can be peeled off from the base material and pasted on the written information. Therefore, the same effect as the second embodiment can be obtained.

  Note that the same configuration as that described in the information recording medium 1a of FIG. 4 can be applied to the second and third embodiments. That is, an infrared fluorescent layer 13a similar to that described with reference to FIG. 4 is provided on the base material 11 which is a postcard paper, and further, a layer containing a material that transmits infrared rays and absorbs the infrared absorbing material 15 thereon. 18 may be provided. This also provides the same effect. In addition, it is also suitable that the infrared fluorescent layer 13a is protected. On the other hand, the second and third embodiments are the same as the first embodiment in that the postcard can be formed thin.

  The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to such examples. It will be apparent to those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea disclosed in the present application, and these naturally belong to the technical scope of the present invention. Understood.

1, 1a: Information recording medium 11: Base material 13, 13a: Infrared fluorescent layer 15: Infrared absorbing material 17: Infrared transmitting / visible light reflecting / absorbing layer 60: Postcard

Claims (7)

  Information characterized in that an infrared phosphor layer including a phosphor that emits infrared rays that have been excited by infrared excitation light and have a peak wavelength different from that of the excitation light, and a material that absorbs the infrared absorbing material is provided on the substrate. recoding media. On the base material, an infrared fluorescent layer including a phosphor that is excited by infrared excitation light and emits infrared light having a peak wavelength different from that of the excitation light is provided.
An information recording medium comprising a layer that contains a material that absorbs an infrared absorbing material and that transmits infrared light on the infrared fluorescent layer.   3. The information recording medium according to claim 1, wherein the material that absorbs the infrared absorbing material is a porous material.   The information recording medium according to any one of claims 1 to 3, wherein a layer that transmits infrared light and reflects or absorbs visible light is provided so as to cover the infrared fluorescent layer.   The information recording medium according to claim 4, wherein the layer that transmits infrared rays and reflects or absorbs visible light is provided so as to be separable.   A postcard, wherein a postcard paper is provided with a phosphor that emits infrared light that is excited by infrared excitation light and has a peak wavelength different from that of the excitation light, and an infrared fluorescent layer that includes a material that absorbs an infrared absorbing material. The postcard paper is provided with an infrared fluorescent layer including a phosphor that emits infrared light that is excited by infrared excitation light and has a peak wavelength different from that of the excitation light.
A postcard comprising a layer containing an infrared absorbing material and transmitting infrared rays on the infrared fluorescent layer.