Information display medium, information writing method, related system and method

Abstract

To provide an information display medium, a method for writing information, a related system, and a method which can be used in movement control of a moving object in a room.SOLUTION: Provided is an information display medium including an information display part that includes at least in part an infrared ray absorbable material that includes cesium tungsten oxide or 6-lanthanum boride, the infrared ray absorbability of a target portion of which, in at least a prescribed wavelength range, decreases when the target portion that includes the infrared ray absorbable material is irradiated with laser light, the distribution of infrared ray absorbability in the information display part indicating designated information for a moving object.SELECTED DRAWING: Figure 44

Description

[Technical field]

[0001] The present invention relates to an information display medium that displays information that can be recognized by a near-infrared camera or the like, an information writing method for writing such information onto the medium, and related systems and methods. [Background technology]

[0002] In recent years, development of vehicles that can move autonomously without being operated by a human, such as self-driving cars, has progressed.

[0003] Patent document 1 describes an autonomous vehicle that transmits a detection signal toward a preset range, acquires reflected signals, sets at least two detected objects as targets, sets a reference line passing through these positions, and drives the vehicle by switching steering operations along the reference line while maintaining the distance between the vehicle body and the reference line within a set range.

[0004] However, the self-driving vehicle of Patent Document 1 is premised on the existence of two or more targets, and since a large number of targets are required to enable the self-driving vehicle to travel automatically along complex routes, it may not be possible to use the self-driving vehicle of Patent Document 1 in featureless, monotonous environments (where there are not a sufficient number of targets) such as indoors. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2016-66208 A [Patent Document 2] JP 2019-159850 A [Patent Document 3] Patent No. 4323578 [Patent Document 4] Special Publication No. 2005-505444 [Patent Document 5] JP 2005-246821 A [Patent Document 6] JP 2008-162233 A [Patent Document 7] Patent No. 6443597 [Patent Document 8] Patent No. 6507096 [Patent Document 9] Patent No. 6541400 [Patent Document 10] Patent No. 6160830 [Patent Document 11] Patent No. 5854329 [Patent Document 12] International Publication No. 2018 / 151238 [Patent Document 13] Patent No. 6167803 [Patent Document 14] Special table number 2006-518898 [Patent Document 15] Patent No. 4391103 [Patent Document 16] Patent No. 5644896 Summary of the Invention [Problem to be solved by the invention]

[0006] In view of the above, an object of the present invention is to provide an information display medium, an information writing method, and related systems and methods that can be used to control the operation of a mobile object even indoors. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, the present invention provides an information display medium comprising an information display section which at least partially contains a near-infrared absorbing material including cesium tungsten oxide or lanthanum hexaboride, and which is characterized in that when laser light is applied to a target section containing the near-infrared absorbing material, the near-infrared absorbency of the target section at least in a predetermined wavelength range is reduced, and the distribution of near-infrared absorbency within the information display section indicates instruction information for a moving body.

[0008] The information display medium may be configured as a laminate including a substrate layer having near-infrared transmissivity or reflectivity, and a near-infrared absorbing layer including a near-infrared absorbing material including cesium tungsten oxide or lanthanum hexaboride, and the near-infrared absorbing layer may include an information display portion.

[0009] The information display medium may further include a printed layer containing a colored ink composition or a fluorescent ink composition, and the printed layer and the information display portion may at least partially overlap each other.

[0010] The print layer may be a print layer that displays an in-plane pattern similar to the in-plane pattern of the surface on which the information display medium is placed.

[0011] The information display medium may be configured as a laminate including a base layer, a first near-infrared absorbing layer including a first near-infrared absorbing material that is a near-infrared absorbing material including cesium tungsten oxide or lanthanum hexaboride, and a second near-infrared absorbing layer including a second near-infrared absorbing material different from cesium tungsten oxide and lanthanum hexaboride, and the first near-infrared absorbing layer may include an information display portion.

[0012] The information display medium may be configured as a laminate including a base layer and a near-infrared absorbing layer, and the near-infrared absorbing layer may include a first region including a first near-infrared absorbing material that is a near-infrared absorbing material including cesium tungsten oxide or lanthanum hexaboride, and a second region including a second near-infrared absorbing material different from cesium tungsten oxide and lanthanum hexaboride, and the first region may include the information display portion.

[0013] The second near infrared absorbing material may include one or more of antimony tin oxide, indium tin oxide, and copper pyrophosphate.

[0014] The information display medium may be configured as a laminate including a base layer, a near-infrared absorbing layer including a near-infrared absorbing material including cesium tungsten oxide or lanthanum hexaboride, and a near-infrared reflective layer including a near-infrared reflective material, and the near-infrared absorbing layer may include an information display portion.

[0015] The near infrared reflective material may include one or more of titanium oxide, silicon oxide, and tin oxide.

[0016] The present invention also provides a system comprising any of the above-mentioned information display media and a mobile body, wherein the mobile body comprises a near-infrared imaging unit that images the information display portion of the information display medium, and an operation control unit that controls the operation of the mobile body using instruction information obtained by imaging with the near-infrared imaging unit.

[0017] The present invention also provides an information writing method for writing instruction information for a moving body into an information display portion of an information display medium which at least partially contains a near-infrared absorbing material including cesium tungsten oxide or lanthanum hexaboride, and which has an information display portion in which the near-infrared absorptivity of the target portion at least in a predetermined wavelength range is reduced by applying laser light to the information display portion of the information display medium, thereby changing the distribution of near-infrared absorptivity within the information display portion.

[0018] The information display medium may be configured as a laminate including a base layer having near-infrared transmissivity or reflectivity and a near-infrared absorbing layer including a near-infrared absorbing material including cesium tungsten oxide or lanthanum hexaboride, and the near-infrared absorbing layer may include an information display portion.

[0019] The information display medium may further include a printed layer containing a colored ink composition or a fluorescent ink composition, and the printed layer and the information display portion may at least partially overlap each other.

[0020] The print layer may be a print layer that displays an in-plane pattern similar to the in-plane pattern of the surface on which the information display medium is placed.

[0021] The information display medium may be configured as a laminate including a base layer, a first near-infrared absorbing layer including a first near-infrared absorbing material that is a near-infrared absorbing material including cesium tungsten oxide or lanthanum hexaboride, and a second near-infrared absorbing layer including a second near-infrared absorbing material different from cesium tungsten oxide and lanthanum hexaboride, and the first near-infrared absorbing layer may include an information display portion.

[0022] The information display medium may be configured as a laminate including a base layer and a near-infrared absorbing layer, and the near-infrared absorbing layer may include a first region including a first near-infrared absorbing material that is a near-infrared absorbing material including cesium tungsten oxide or lanthanum hexaboride, and a second region including a second near-infrared absorbing material different from cesium tungsten oxide and lanthanum hexaboride, and the first region may include the information display portion.

[0023] The second near infrared absorbing material may include one or more of antimony tin oxide, indium tin oxide, and copper pyrophosphate.

[0024] The information display medium may be configured as a laminate including a base layer, a near-infrared absorbing layer including a near-infrared absorbing material including cesium tungsten oxide or lanthanum hexaboride, and a near-infrared reflective layer including a near-infrared reflective material, and the near-infrared absorbing layer may include the information display portion.

[0025] The near infrared reflective material may include one or more of titanium oxide, silicon oxide, and tin oxide.

[0026] The present invention also provides a method for controlling the operation of a moving body equipped with a near-infrared imaging unit and an operation control unit, the method including the near-infrared imaging unit imaging an information display unit of any of the above-mentioned information display media, and the operation control unit controlling the operation of the moving body using instruction information obtained by imaging by the near-infrared imaging unit. Effect of the Invention

[0027] According to the present invention, it is possible to print variable invisible identification information by changing the infrared absorption performance by applying laser light to a medium containing a colorless or colored infrared absorbing material. For example, if instruction information (information instructing an action, information instructing a position, etc.) for a moving body such as a vehicle or a robot is printed on the medium as invisible code information that cannot be seen by the naked eye and is not noticeable, a near-infrared camera or the like mounted on the moving body can read the instruction information to control the operation of the moving body, allowing the moving body to move autonomously. [Brief description of the drawings]

[0028] [Figure 1] 3 is a diagram showing an observation image (visible light image) of a cross section (A-A' cross section cut along line A-A' in FIG. 3 etc.; the same applies to other figures) of the information display medium in the first embodiment of the present invention under visible light. [Diagram 2] FIG. 1 is a diagram showing an observation image (near-infrared image) of a cross section of an information display medium in a first embodiment of the present invention taken with a near-infrared camera (note that the outline of the medium has been drawn in to make the image easier to see; the same applies to the other figures). [Diagram 3] 1 is a diagram showing an observed image (visible light image) of a surface (surface seen in the direction of arrow L in FIG. 1; the same applies to other figures) of an information display medium in a first embodiment of the present invention under visible light. [Figure 4] 1 is a diagram showing an observation image (near-infrared image) of the surface of the information display medium in the first embodiment of the present invention taken with a near-infrared camera. [Diagram 5]1 etc. is irradiated with laser light in the direction of arrow L, and the near-infrared absorption of the information display medium at the portion where the laser light hits is reduced (near-infrared image, cross-sectional view). [Figure 6] FIG. 6 is a diagram (near-infrared image, surface diagram) showing an observed image of the surface when laser light is irradiated onto the medium and instruction information (marker information such as ArUco marker) is written onto the medium as shown in FIG. 5. [Figure 7] A diagram (near-infrared image, surface diagram) showing an observed image of the surface when laser light is irradiated onto the medium and instruction information (two-dimensional code information) is written onto the medium as shown in Figure 5. [Figure 8] FIG. 11 is a diagram showing an observation image (visible light image) of a cross section of an information display medium (laminate) according to a second embodiment of the present invention, observed under visible light. [Figure 9] FIG. 13 is a view showing an observation image (near-infrared image) of a cross section of a laminate in a second embodiment of the present invention taken with a near-infrared camera. [Figure 10] 9 is a diagram (near-infrared image, cross-sectional view) showing that the near-infrared absorptivity of the information display medium is reduced in the portion hit by the laser light when the laminate shown in FIG. 8 etc. is irradiated with laser light in the direction of arrow L. [Figure 11] 13 is a diagram showing an observation image (visible light image) of a cross section (A-A' cross section cut along line A-A' in FIG. 13 etc.; the same applies to other figures) of a laminate in a third embodiment of the present invention under visible light. FIG. [Figure 12] FIG. 13 is a view showing an observation image (near-infrared image) of a cross section of a laminate in a third embodiment of the present invention taken with a near-infrared camera. [Figure 13] 11 is a diagram showing an observation image (visible light image) of a surface (surface seen in the direction of arrow L in FIG. 11; the same applies to other figures) of a laminate in a third embodiment of the present invention under visible light. [Figure 14] FIG. 13 is a diagram showing an image (near-infrared image) of the surface of a laminate in a third embodiment of the present invention observed by a near-infrared camera. [Figure 15]12 is a diagram (near-infrared image, cross-sectional view) showing that the near-infrared absorbency of the laminate shown in FIG. 11 etc. was reduced in the portion of the laminate where the laser light was irradiated in the direction of the arrow L. [Figure 16] FIG. 16 is a diagram showing an observed image of the surface when laser light is irradiated as shown in FIG. 15 and instruction information is written into the laminate (near-infrared image, surface view). [Figure 17] FIG. 13 is a view showing an observation image (visible light image) of a cross section of a laminate according to a fourth embodiment of the present invention under visible light. [Figure 18] FIG. 13 is a view showing an observation image (near-infrared image) of a cross section of a laminate in a fourth embodiment of the present invention taken with a near-infrared camera. [Figure 19] 17 etc. was irradiated with laser light in the direction of arrow L, and the near-infrared absorbency of the laminate was reduced in the portion where the laser light hit (near-infrared image, cross-sectional view). [Figure 20] 22 and 23. FIG. 22 is a diagram showing an observation image (visible light image) of a cross section (A-A' cross section cut along line A-A' in FIG. 22 and the like; the same applies to other figures) of a laminate in a fifth embodiment of the present invention under visible light. [Figure 21] FIG. 13 is a view showing an observation image (near-infrared image) of a cross section of a laminate in a fifth embodiment of the present invention taken with a near-infrared camera. [Figure 22] 20 is a diagram showing an observation image (visible light image) of a surface (surface seen in the direction of arrow L in FIG. 20; the same applies to other figures) of a laminate in a fifth embodiment of the present invention under visible light. FIG. [Figure 23] FIG. 13 is a view showing an image (near-infrared image) of the surface of a laminate in a fifth embodiment of the present invention observed by a near-infrared camera. [Figure 24] 20, etc. was irradiated with laser light in the direction of arrow L, and the near-infrared absorbency of the laminate was reduced in the portion where the laser light hit (near-infrared image, cross-sectional view). [Diagram 25] FIG. 25 is a diagram showing an observed image of the surface when laser light is irradiated as shown in FIG. 24 and instruction information is written into the laminate (near-infrared image, surface view). [Figure 26]FIG. 13 is a view showing an observation image (visible light image) of a cross section of a laminate according to a sixth embodiment of the present invention under visible light. [Figure 27] FIG. 13 is a view showing an observation image (near-infrared image) of a cross section of a laminate in a sixth embodiment of the present invention taken with a near-infrared camera. [Figure 28] 27 is a diagram (near-infrared image, cross-sectional view) showing that the near-infrared absorbency of the laminate shown in FIG. 26 etc. was reduced in the portion of the laminate where the laser light was irradiated. [Figure 29] 31 shows an observation image (visible light image) of a cross section (A-A' cross section cut along line A-A' in FIG. 31 etc.; the same applies to other figures) of a laminate in a seventh embodiment of the present invention under visible light. FIG. [Diagram 30] FIG. 23 is a view showing an observation image (near-infrared image) of a cross section of a laminate in a seventh embodiment of the present invention taken with a near-infrared camera. [Diagram 31] 29 is a diagram showing an observation image (visible light image) of a surface of a laminate in a seventh embodiment of the present invention under visible light (the surface seen in the direction of arrow L in FIG. 29; the same applies to other figures). FIG. [Diagram 32] FIG. 23 is a view showing an observation image (near-infrared image) of the surface of a laminate in a seventh embodiment of the present invention taken with a near-infrared camera. [Diagram 33] 29, etc., was irradiated with laser light in the direction of arrow L, and the near-infrared absorbency of the laminate was reduced in the portion where the laser light was irradiated (near-infrared image, cross-sectional view). [Diagram 34] FIG. 34 is a diagram showing an observed image of the surface when laser light is irradiated onto the medium and instruction information is written onto the medium as shown in FIG. 33 (near-infrared image, surface view). [Diagram 35] FIG. 23 is a view showing an observation image (visible light image) of a cross section of a laminate in an eighth embodiment of the present invention under visible light. [Diagram 36] FIG. 23 is a view showing an observation image (near-infrared image) of a cross section of a laminate in an eighth embodiment of the present invention taken with a near-infrared camera. [Figure 37]36 is a diagram (near-infrared image, cross-sectional view) showing that the near-infrared absorbency of the laminate shown in FIG. 35 etc. was reduced in the portion of the laminate where the laser light was hit. [Figure 38] FIG. 23 is a view showing an observation image (visible light image) of a cross section of a laminate in a ninth embodiment of the present invention under visible light. [Figure 39] FIG. 13 is a view showing an observation image (near-infrared image) of a cross section of a laminate in a ninth embodiment of the present invention taken with a near-infrared camera. [Diagram 40] 38, etc., was irradiated with laser light in the direction of arrow L, resulting in a decrease in near-infrared absorbency in the portion of the laminate where the laser light hit (near-infrared image, cross-sectional view). [Diagram 41] FIG. 23 is a view showing an observation image (visible light image) of a cross section of a laminate in a tenth embodiment of the present invention under visible light. [Diagram 42] FIG. 23 is a view showing an observation image (near-infrared image) of a cross section of a laminate in a tenth embodiment of the present invention taken with a near-infrared camera. [Diagram 43] 42 is a diagram (near-infrared image, cross-sectional view) showing that the near-infrared absorbency of the laminate shown in FIG. 41 etc. was reduced in the portion of the laminate where the laser light was irradiated. [Diagram 44] FIG. 1 is a diagram explaining how information display media are attached to indoor walls and a moving body (vehicle) moves autonomously by reading instruction information printed on each information display medium. [Diagram 45] FIG. 2 is a block diagram showing the functional configuration of a moving body (vehicle). [Diagram 46] FIG. 2 is a block diagram showing the functional configuration of an operation control unit of a moving body (vehicle). [Figure 47] FIG. 2 is a block diagram showing the device configuration of a near-infrared camera (near-infrared imaging unit) mounted on a moving object. [Figure 48] 11 is a flowchart of a control operation for controlling the operation of a moving body (vehicle) by reading information written on an information display medium by photographing the information display medium attached to a wall with a near-infrared camera. [Figure 49]13 is a flowchart (continued) of the control operation of controlling the operation of a moving body (vehicle) by reading information written on an information display medium by photographing the information display medium attached to a wall with a near-infrared camera. [Figure 50] FIG. 1 is a diagram explaining how information display media are attached to an indoor ceiling and a moving body (vehicle) moves autonomously by reading instruction information printed on each information display media. [Figure 51] 11 is a flowchart of a control operation for controlling the operation of a moving body (vehicle) by reading information written on an information display medium by photographing the information display medium attached to a ceiling with a near-infrared camera. [Figure 52] 13 is a flowchart (continued) of the control operation of controlling the operation of a moving body (vehicle) by reading information written on an information display medium by photographing the information display medium attached to the ceiling with a near-infrared camera. [Figure 53] FIG. 1 is a diagram illustrating a schematic configuration of a laser marker device. [Figure 54] FIG. 1 shows near-infrared images of a cesium tungsten oxide-containing ink and an ytterbium oxide-containing ink observed with an infrared camera, and a near-infrared image of a printed material obtained by offset printing these inks on a substrate, observed with an infrared camera. [Figure 55] A graph showing the results of measuring the reflectance in the visible to near infrared range of the printed surface before laser marking (before laser marking), and the reflectance in the visible to near infrared range of the laser-marked area on the printed surface of the prints (after laser marking) for prints that were offset printed on various substrates using ink containing cesium tungsten oxide (the graph shows the results of measuring the reflectance on the printed surface side (ink side). The same applies to the other graphs). [Figure 56] This graph is an extract of the measurement results when PC (polycarbonate) was used as the base material from the graph in Figure 55. [Figure 57] This graph is an excerpt from the graph in Figure 55 showing the measurement results when PET-G (amorphous polyester) was used as the base material. [Figure 58]This graph is an extract of the measurement results when PVC (polyvinyl chloride) was used as the base material from the graph in Figure 55. [Figure 59] This graph shows the results of measuring the reflectance of the printed surface in the visible light to near infrared light range when ink compositions with various amounts of cesium tungsten oxide (expressed as content rate, unit: weight percent; wt%) were used for offset printing on high-quality paper as a substrate. [Figure 60] This graph shows the results of measuring the reflectance in the visible to near infrared region of the printed surface before laser printing (before laser printing), and the reflectance in the visible to near infrared region of the laser-printed area of ​​the printed surface of a printed matter that was offset printed using an ink containing lanthanum hexaboride on a PC (polycarbonate) substrate (after laser printing). DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] Hereinafter, an information display medium, an information writing method, and related systems and methods, which are exemplary embodiments of the present invention, will be described with reference to the drawings. However, it should be noted that the information display medium, the information writing method, and related systems and methods according to the present invention are not limited to the specific aspects described below, and can be appropriately modified within the scope of the present invention. Individual functions, elements, etc. included in the embodiments described below can be appropriately deleted or modified within the scope of the present invention, and any functions, elements, etc. not included in the embodiments can be added within the scope of the present invention, and each embodiment can be appropriately combined and implemented. For example, in the following embodiments, the substrate (substrate layer) is described as a transparent substrate or a transparent substrate containing a near-infrared absorbing material, but a colored substrate may be used as the substrate (substrate layer). The medium may be a medium consisting of a single layer, such as a substrate containing a near-infrared absorbing material, or may have a multilayer structure. The medium taught by the present invention may be a medium in which near-infrared information that can be recognized by photographing with a near-infrared camera or the like has already been written by writing by laser marking, or may be a medium for displaying information or for another purpose in which no information has yet been written. The method of forming the near-infrared absorbing layer on the substrate layer or the like may be any method, such as coating of a near-infrared absorbing ink, offset printing using a near-infrared absorbing ink layer, silk screen printing, gravure printing, flexographic printing, inkjet printing, etc. When a plurality of near-infrared absorbing layers are formed, they may be formed by the same method or different methods. The colored printed layer or fluorescent printed layer may also be formed by any method. In the examples described below, it is shown that it is particularly effective to use near-infrared (line) laser light as the laser light, and in each embodiment, the laser light is described as being near-infrared laser light, but the laser light that can be used in the present invention is not limited to this.In other words, it is not necessary to use near-infrared laser light from a near-infrared laser (e.g., Nd:YAG laser, YVO4 laser, fiber laser, etc.) as the laser light, and it is also possible to use laser light from an ultraviolet laser (e.g., THG laser, etc.), visible light laser (e.g., SHG laser, etc.), far-infrared laser (e.g., CO2 laser), etc.

[0030] In the following embodiments, "near infrared" refers to electromagnetic waves having a wavelength of 780 nm to 2000 nm (based on "JIS Z 8117:2002 Far-infrared Terminology"). "Near-infrared laser light (near-infrared laser light)" refers to laser light having a wavelength within the above-mentioned near-infrared wavelength range. "Visible light" refers to electromagnetic waves having a wavelength of 400 nm to 780 nm. In the following embodiments, "near-infrared absorption" refers to the property of absorbing at least a part of the irradiated near-infrared light, "near-infrared transmittance" refers to the property of transmitting at least a part of the irradiated near-infrared light, and "near-infrared reflectance" refers to the property of reflecting at least a part of the irradiated near-infrared light. Similarly, in the following embodiments, "visible light absorption" refers to the property of absorbing at least a part of the irradiated visible light, "visible light transmittance" refers to the property of transmitting at least a part of the irradiated visible light, and "visible light reflectance" refers to the property of reflecting at least a part of the irradiated visible light. In the following embodiments, "laser marking" of a near-infrared absorbing layer or a near-infrared absorbing substrate by a laser beam such as a near-infrared laser beam means drawing (or writing) some display content such as a pattern, a character, or other information on the near-infrared absorbing layer or the near-infrared absorbing substrate by irradiating the near-infrared absorbing layer or the near-infrared absorbing substrate with a laser beam to change the absorption characteristics of the near-infrared absorbing layer or the near-infrared absorbing substrate against near-infrared rays. Laser marking may be performed by irradiating a laser beam to a target portion in the direction of the arrow L in each figure, or in the opposite direction (by irradiating a laser beam from the surface of the medium or laminate 1 opposite to the side of the arrow L in the opposite direction to the arrow L) as long as the laser beam reaches the target portion, or laser marking may be performed by irradiating a laser beam in any direction as long as the laser beam reaches the target portion. Unless otherwise specified, elements with the same reference numerals indicate similar elements between different drawings.

[0031] (First embodiment) FIG. 1 is a diagram showing an observation image (visible light image) of a cross section (A-A' cross section cut along line A-A' in FIG. 3 etc.; similar to other figures) of an information display medium in a first embodiment of the present invention under visible light, FIG. 2 is a diagram showing an observation image (near-infrared image) of a cross section of the information display medium taken with a near-infrared camera, FIG. 3 is a diagram showing an observation image (visible light image) of a surface of the information display medium under visible light (surface seen in the direction of arrow L in FIG. 1; similar to other figures), and FIG. 4 is a diagram showing an observation image (near-infrared image) of the surface of the information display medium taken with a near-infrared camera. In addition, although an outer frame is drawn in the visible light images of Fig. 1 and Fig. 3, this is drawn for convenience to make the drawings easier to see, and as described later, when a near-infrared absorbing substrate 2 is produced using a resin to which a near-infrared absorbing material containing one or both of cesium tungsten oxide and lanthanum hexaboride is added when producing a transparent sheet, the near-infrared absorbing substrate 2 is impossible or at least difficult to recognize in the visible light region (an outer frame is similarly drawn for convenience in the visible light images and near-infrared images of other embodiments). The information display medium 1 is made of a near-infrared absorbing substrate 2 containing a near-infrared absorbing material containing one or both of cesium tungsten oxide and lanthanum hexaboride, and by laser marking by irradiating a laser beam, instruction information for a moving object can be written in the information display medium 1 as information that can be read by a near-infrared camera or the like but is at least difficult to recognize by a visible light camera or the naked eye (the distribution of near-infrared absorptivity in the near-infrared absorbing substrate 2 after laser marking indicates instruction information for a moving object). The near-infrared absorbing substrate 2 can be produced by using a resin to which a near-infrared absorbing material containing either or both of cesium tungsten oxide and lanthanum hexaboride has been added when producing a transparent sheet (transparent to visible light and near-infrared rays) using materials such as PVC (polyvinyl chloride), PET-G (amorphous polyester), PC (polycarbonate), PET (polyethylene terephthalate), and PP (polypropylene), and by a sheet-making method such as extrusion molding or calendar molding.In another example, one or both of cesium tungsten oxide and lanthanum hexaboride are added to a transparent material (having visible light transmittance and near-infrared transmittance) such as PVC (polyvinyl chloride), PET-G (amorphous polyester), PC (polycarbonate), PET (polyethylene terephthalate), PP (polypropylene), transparent resin, etc., which is in a liquid state that has been heated and melted, and then mixed, molded into the shape of the near-infrared absorbing substrate 2, and solidified, thereby producing the near-infrared absorbing substrate 2. The near-infrared absorbing substrate 2 preferably has a visible light transmittance of 50% or more and a near-infrared transmittance of 50% or more, but the near-infrared absorbing substrate 2 may be produced in a mode that does not satisfy this condition.

[0032] As described above, cesium tungsten oxide or lanthanum hexaboride can be used as the near-infrared absorbing material to be contained in the near-infrared absorbing substrate 2. Cesium tungsten oxide is represented by the chemical formula (general formula) Cs x W y O z (x, y, z are positive real numbers). In one example, cesium tungsten oxide having a hexagonal crystal structure, which is described in Patent Document 10 (Japanese Patent No. 6160830), can be used. 0.33Fine particles represented by WO3 can be used. Fine particles represented by the chemical formula LaB6 can be used as lanthanum hexaboride. The content of cesium tungsten oxide in the near-infrared absorbing substrate 2 is arbitrary, but as shown in the examples described later, the ink containing cesium tungsten oxide has good properties at a cesium tungsten oxide content of 0.5% by weight (weight percent) to 6% by weight in one example, so the content of cesium tungsten oxide in the near-infrared absorbing substrate 2 may also be 0.5% by weight (weight percent) to 6% by weight. The content of lanthanum hexaboride in the near-infrared absorbing substrate 2 is also arbitrary, and may be 0.05% by weight (weight percent) to 6% by weight in one example, but as shown in the examples described later, the ink containing lanthanum hexaboride has good properties at a lanthanum hexaboride content of 0.3% by weight in one example, so the content of lanthanum hexaboride in the near-infrared absorbing substrate 2 may also be 0.3% by weight. Even when a near-infrared absorbing substrate 2 containing both cesium tungsten oxide and lanthanum hexaboride is used, the respective contents of cesium tungsten oxide and lanthanum hexaboride are similarly arbitrary. Note that the "content (wt%) of cesium tungsten oxide" in the near-infrared absorbing substrate 2 refers to the weight ratio of cesium tungsten oxide contained in the near-infrared absorbing substrate 2 to the total weight of the near-infrared absorbing substrate 2, Content of cesium tungsten oxide in near-infrared absorbing base material 2 (wt%)={(weight of cesium tungsten oxide) / (total weight of near-infrared absorbing base material 2)}×100 It is expressed by: Similarly, the "content (wt%) of lanthanum hexaboride" in the near-infrared absorbing substrate 2 is the ratio of the weight of lanthanum hexaboride contained in the near-infrared absorbing substrate 2 to the total weight of the near-infrared absorbing substrate 2, Content (wt%) of lanthanum hexaboride in near-infrared absorbing substrate 2={(weight of lanthanum hexaboride) / (total weight of near-infrared absorbing substrate 2)}×100 It is expressed by:

[0033] Such a near-infrared absorbing substrate 2 has visible light transparency and near-infrared transparency, while also having a certain degree of near-infrared absorption due to the inclusion of a near-infrared absorbing material. Therefore, when the near-infrared absorbing substrate 2 is photographed with a near-infrared camera or the like, a darker near-infrared image is obtained compared to a member made only of a transparent material. As will be explained later using experimental results, cesium tungsten oxide and lanthanum hexaboride have the property that their near-infrared absorption decreases when irradiated with (near-infrared) laser light. Therefore, by irradiating near-infrared laser light on near-infrared absorbing substrate 2 containing at least one of cesium tungsten oxide and lanthanum hexaboride in a manner similar to drawing (writing) an image, character, code information, or the like by laser marking, the near-infrared absorption characteristics of the drawn portion change (the decrease in near-infrared absorbency increases the near-infrared transmittance of the target portion of the laser marking compared to before the laser light was irradiated, and when photographed with a near-infrared camera, part of the near-infrared light (from the near-infrared camera light source or from the surrounding area) passes through the target portion and is reflected by an object or the like behind the target portion, thereby obtaining a near-infrared image of the target portion that is brighter than that before the laser marking). This makes it possible to display information such as images, characters, code information, etc., on near-infrared absorbing substrate 2, which is at least difficult to recognize with the naked eye or a visible light camera but can be recognized by a near-infrared camera or the like.

[0034] FIG. 5 is a diagram (near-infrared image, cross-sectional view) showing that the near-infrared absorbency of the portion of the information display medium where the laser light hits (referred to as "portion 3 irradiated with laser light"; the same applies to other diagrams) is reduced when the information display medium shown in FIG. 1 etc. is irradiated with laser light in the direction of the arrow L. Any information can be written on the near-infrared absorbing substrate 2 by laser marking using a laser marker device or the like. Examples of information that can be written are shown in FIGS. 6 to 7. FIG. 6 is a diagram (near-infrared image, surface view) showing an observation image of the surface when the medium is irradiated with laser light as shown in FIG. 5 and instruction information (marker information such as ArUco marker) is written on the medium, and FIG. 7 is a diagram (near-infrared image, surface view) showing an observation image of the surface when the medium is irradiated with laser light as shown in FIG. 5 and two-dimensional code information such as QR code (registered trademark) is written on the medium as instruction information. As shown in the experimental results in Figs. 55 to 58 and 60 described later, in the near-infrared absorbing layer printed with near-infrared absorbing ink containing cesium tungsten oxide or lanthanum hexaboride, the reflectance in the near-infrared region changes significantly upon irradiation with near-infrared laser light, while the reflectance in the visible light region does not change significantly before and after irradiation with near-infrared laser light. Therefore, even if information recognizable as a near-infrared image as shown in Figs. 6 and 7 is written by irradiation with (near-infrared) laser light, information such as marker information and two-dimensional code information is impossible or at least difficult to recognize in the visible light image of the information display medium 1 (similar to other embodiments). That is, this information is impossible or at least difficult to recognize with the naked eye or a visible light camera, but can be obtained by photographing with a near-infrared camera, and by attaching an information display medium on which such instruction information (instruction information for a moving object) is written to a wall, ceiling, object, etc., it becomes possible to control the operation of the moving object without impairing the design. In each of the embodiments described later, instruction information for a mobile object can be written in the (first) near-infrared absorbing layer 4 by laser marking.

[0035] The near-infrared absorbing substrate 2 may be a paper substrate containing at least one of cesium tungsten oxide and lanthanum hexaboride. In this case, such a near-infrared absorbing substrate 2 can be produced by adding the near-infrared absorbing material to the pulp (raw material) used in the papermaking process beforehand and then putting the pulp into the papermaking process, or by adding the near-infrared absorbing material to the paint applied to the front side of the paper in the papermaking process beforehand (when the near-infrared absorbing material is added to the paint in this way, the cross-sectional views will be similar to those of Figs. 8 to 10 shown as the second embodiment described later), etc. In view of the experimental results described later, it is believed that the near-infrared absorption of the target portion of the near-infrared absorbing substrate 2 containing cesium tungsten oxide or lanthanum hexaboride is reduced at least in a predetermined wavelength range (for example, the near-infrared region of 780 nm to 2000 nm for a substrate containing cesium tungsten oxide, and the near-infrared region of 780 nm to 1400 nm for a substrate containing lanthanum hexaboride) by applying laser light to the target portion, as in the case of printing on a substrate using a near-infrared absorbing ink composition containing cesium tungsten oxide or lanthanum hexaboride. Therefore, it is believed that the near-infrared absorbing substrate 2 can be irradiated with (near-infrared) laser light to write (draw) an image, character, code information, etc., and then the near-infrared image can be observed by photographing it with a near-infrared camera, etc., to confirm the image, character, code information, etc. written (drawn) by laser marking. Laser marking may be performed by irradiating the near-infrared absorbing substrate 2 from below, rather than from the direction of arrow L in FIG. 1 (from above, the infrared absorbing substrate 2 in the medium 1).

[0036] Second embodiment FIG. 8 is a diagram showing an observation image (visible light image) of a cross section of an information display medium (laminate) in the second embodiment of the present invention under visible light (the surface view is the same as FIG. 3, but the reference number "2" is replaced with the reference number "4"). FIG. 9 is a diagram showing an observation image (near-infrared image) of a cross section of a laminate in the second embodiment of the present invention observed by a near-infrared camera (the surface view is the same as FIG. 4, but the reference number "2" is replaced with the reference number "4"). FIG. 10 is a diagram (near-infrared image, cross-sectional view) showing that the near-infrared absorption property of the part of the information display medium where the laser light hits is reduced when the laminate shown in FIG. 8 etc. is irradiated with laser light in the direction of arrow L. Unlike the medium 1 in the first embodiment, the laminate 1 in the second embodiment includes a base layer 2 and a near-infrared absorption layer 4.

[0037] The substrate layer 2 may be a transparent sheet (having visible light transmittance and near-infrared transmittance) made of a material such as PVC (polyvinyl chloride), PET-G (amorphous polyester), PC (polycarbonate), PET (polyethylene terephthalate), or PP (polypropylene), or may be a paper substrate (such as fine paper or corded paper) (having visible light reflectance and near-infrared reflectance). The near-infrared absorbing layer 4 is a near-infrared absorbing layer containing the near-infrared absorbing material containing cesium tungsten oxide or lanthanum hexaboride described above, and in one example, it can be formed by applying a near-infrared absorbing ink containing one or both of cesium tungsten oxide and lanthanum hexaboride to the substrate layer 2, or by printing the substrate layer 2 with such a near-infrared absorbing ink.

[0038] As will be explained later with experimental results, the near-infrared absorbing ink composition containing cesium tungsten oxide or lanthanum hexaboride has the property that the absorptivity for near-infrared rays in at least a predetermined wavelength range decreases (the reflectivity increases) when exposed to near-infrared laser light. When near-infrared laser light is applied to a near-infrared absorbing layer formed by coating, printing, or the like using such a near-infrared absorbing ink composition so as to draw characters, images (pictures, figures, etc.), code information, etc. (laser marking), the near-infrared absorption characteristics of the drawn portion change, and thus characters, images, code information, etc. that can be recognized using an infrared camera, etc. but that are impossible or at least difficult to recognize with the naked eye or a visible light camera are formed on the near-infrared absorbing layer (the distribution of near-infrared absorptivity in the near-infrared absorbing layer 4 after laser marking indicates instruction information for a moving body. The same applies to the embodiments described later). For example, by performing laser marking on the near-infrared absorbing layer 4 so as to draw marker information such as a barcode, a two-dimensional code, numerical information, or an ArUco marker, it is possible to write information similar to that shown in the above-mentioned FIGS. 6 to 7 (marker information and two-dimensional code information are illustrated as examples, but any information such as a barcode or numerical information can be written) on the near-infrared absorbing layer 4 (reference numeral "2" in FIGS. 6 to 7 is replaced with reference numeral "4"). When the base layer 2 is a base layer having near-infrared transmittance such as a transparent base material, laser marking may be performed by irradiating the near-infrared absorbing layer 4 with a laser beam from the base layer 2 side, not in the direction of the arrow L in FIG. 8 (from the side of the first near-infrared absorbing layer 4 in the laminate 1).

[0039] The ink composition containing cesium tungsten oxide has the chemical formula (general formula) Cs x W y O z (x, y, z are positive real numbers). In one example, ink containing cesium tungsten oxide having a hexagonal crystal structure, as described in Patent Document 10 (Japanese Patent No. 6160830), can be used. 0.33Ink containing fine particles represented by WO3 can be used. As the lanthanum hexaboride-containing ink composition, ink containing fine particles represented by the chemical formula LaB6 can be used. The near-infrared absorbing ink contains dispersants, monomers, synthetic resins, auxiliaries, and the like in addition to cesium tungsten oxide or lanthanum hexaboride. The content of cesium tungsten oxide in the cesium tungsten oxide-containing ink is arbitrary, but in one example, it is shown in the examples below that the ink has good properties at a content of 0.5% by weight (weight percent) to 6% by weight. The content of lanthanum hexaboride in the lanthanum hexaboride-containing ink is also arbitrary, and in one example, it may be 0.05% by weight (weight percent) to 6% by weight, but in the examples below, it is shown that the ink has good properties at a content of 0.3% by weight. When using a near-infrared absorbing ink containing both cesium tungsten oxide and lanthanum hexaboride, the respective contents of cesium tungsten oxide and lanthanum hexaboride are similarly arbitrary. In either case, the preferred content can be changed depending on the printing density (amount applied), etc. Note that the "cesium tungsten oxide content (wt%)" here refers to the weight ratio of cesium tungsten oxide contained in the ink to the total weight of the ink, Content of cesium tungsten oxide in ink (% by weight) = {(weight of cesium tungsten oxide) / (total weight of ink)} x 100 It is expressed by: Similarly, "Lanthanum hexaboride content (wt%)" is the weight ratio of lanthanum hexaboride contained in the ink to the total weight of the ink, Content of lanthanum hexaboride in ink (% by weight) = {(weight of lanthanum hexaboride) / (total weight of ink)} x 100 It is expressed by:

[0040] Third embodiment FIG. 11 is a diagram showing an observation image (visible light image) of a cross section (A-A' cross section cut along line A-A' in FIG. 13, etc.; similar to other figures) of a laminate in the third embodiment of the present invention, taken under visible light; FIG. 12 is a diagram showing an observation image (near-infrared image) of a cross section of the laminate, taken with a near-infrared camera; FIG. 13 is a diagram showing an observation image (visible light image) of a surface of the laminate, taken under visible light (surface visible in the direction of arrow L in FIG. 11; similar to other figures); and FIG. 14 is a diagram showing an observation image (near-infrared image) of the surface of the laminate, taken with a near-infrared camera.

[0041] The laminate 1 of the third embodiment includes a colored printed layer or a fluorescent printed layer 5 between a base layer 2 and a (first) near-infrared absorbing layer 4. The base layer 2 may be a transparent sheet similar to that of the second embodiment, or a paper base material, and the first near-infrared absorbing layer 4 is a layer formed using a near-infrared absorbing ink containing one or both of cesium tungsten oxide and lanthanum hexaboride similar to that of the second embodiment, while the colored printed layer or the fluorescent printed layer 5 is a printed layer formed by printing using a colored ink or a fluorescent ink.

[0042] In one example, the colored printed layer or fluorescent printed layer 5 is formed by printing on the base material layer 2 using a near-infrared transparent colored ink (a visible light absorbing colored ink) such as UV SOYBI SG Yellow (manufactured by DIC Graphics), UV SOYBI SG Red (manufactured by DIC Graphics), UV SOYBI SG Blue (manufactured by DIC Graphics), UV 161 Yellow S (manufactured by T&K TOKA), UV 161 Red S (manufactured by T&K TOKA), UV 161 Blue S (manufactured by T&K TOKA), and / or a near-infrared transparent fluorescent ink such as UV Fluorescent Medium B (manufactured by T&K TOKA), UV Fluorescent Medium Y (manufactured by T&K TOKA), UV Fluorescent Medium R (manufactured by T&K TOKA), etc. When printing with colored inks or fluorescent inks, the laminate 1 can be made less noticeable by printing an in-plane pattern (such as a wallpaper pattern) similar to the in-plane pattern of the surface to which the laminate 1 will be attached, such as a wall or ceiling surface.

[0043] The laminate 1 shown in Figure 11 etc. can be produced by printing on a base layer 2 using the above-mentioned colored ink and / or fluorescent ink to form a colored printed layer or fluorescent printed layer 5, and then printing on the colored printed layer or fluorescent printed layer 5 using a near-infrared absorbing ink containing one or both of cesium tungsten oxide and lanthanum hexaboride, or by applying such a near-infrared absorbing ink onto the colored printed layer or fluorescent printed layer 5 to form a near-infrared absorbing layer 4.

[0044] FIG. 15 is a diagram (near-infrared image, cross-sectional view) showing that the near-infrared absorbency of the part of the laminate where the laser light hits is reduced when the laminate shown in FIG. 11 etc. is irradiated with laser light in the direction of the arrow L, and FIG. 16 is a diagram (near-infrared image, surface view) showing an observation image of the surface when the laminate is irradiated with laser light as shown in FIG. 15 and instruction information is written. As in the second embodiment, by performing laser marking on the near-infrared absorbing layer 4 so as to write instruction information for a moving object, for example, an information display medium 1 that is impossible or at least difficult to recognize with the naked eye or a visible light camera but can be read by a near-infrared camera can be obtained. Note that, when the base layer 2 is a base layer having near-infrared transmittance such as a transparent base layer, and the colored printed layer or fluorescent printed layer 5 transmits near-infrared rays at least in part, the first near-infrared absorbing layer 4 may be irradiated with laser light from the side of the base layer 2 to perform laser marking, not in the direction of the arrow L in FIG. 11 (from the side of the first near-infrared absorbing layer 4 in the laminate 1).

[0045] (Fourth embodiment) FIG. 17 is a diagram showing an observation image (visible light image) of a cross section of a laminate in the fourth embodiment of the present invention under visible light (surface view is similar to FIG. 13), FIG. 18 is a diagram showing an observation image (near-infrared image) of a cross section of the laminate taken with a near-infrared camera (surface view is similar to FIG. 14), and FIG. 19 is a diagram (near-infrared image, cross-sectional view) showing that the near-infrared absorbency of the portion of the laminate hit by the laser light is reduced when the laminate is irradiated with laser light in the direction of arrow L (surface view is similar to FIG. 16).

[0046] In the laminate 1 of the fourth embodiment, the order of lamination of the near-infrared absorbing layer 4 and the colored printed layer or fluorescent printed layer 5 is reversed compared to the laminate 1 of the third embodiment, but the other configurations may be the same as those of the third embodiment, and by performing laser marking on the near-infrared absorbing layer 4 as shown in Fig. 19, information that is at least difficult to recognize with a visible light camera or the naked eye but can be recognized by a near-infrared camera can be written. When the base layer 2 is a base layer having near-infrared transmittance such as a transparent base material, laser marking may be performed by irradiating the first near-infrared absorbing layer 4 with laser light from the side of the base layer 2, not in the direction of the arrow L in Fig. 19 (from the side of the colored printed layer or fluorescent printed layer 5 in the laminate 1). The laminate 1 shown in FIG. 17 etc. can be produced by printing on the base layer 2 using a near-infrared absorbing ink containing one or both of cesium tungsten oxide and lanthanum hexaboride, or by applying such near-infrared absorbing ink to the base layer 2 to form a near-infrared absorbing layer 4, and further forming a colored printed layer or fluorescent printed layer 5 on the surface of the base layer 2 facing the near-infrared absorbing layer 4 by printing with a colored ink or a fluorescent ink so as to at least partially overlap the near-infrared absorbing layer 4 (in one example, a pattern similar to that of the surface to which the information display medium 1 is attached, such as a wall surface or a ceiling surface, is printed).

[0047] Fifth embodiment FIG. 20 is a diagram showing an observation image (visible light image) of a cross section (A-A' cross section cut along line A-A' in FIG. 22, etc.; similar to other figures) of a laminate in the fifth embodiment of the present invention, taken under visible light; FIG. 21 is a diagram showing an observation image (near-infrared image) of a cross section of the laminate, taken with a near-infrared camera; FIG. 22 is a diagram showing an observation image (visible light image) of the surface of the laminate, taken under visible light (surface visible in the direction of arrow L in FIG. 20; similar to other figures); and FIG. 23 is a diagram showing an observation image (near-infrared image) of the surface of the laminate, taken with a near-infrared camera. With regard to the surface view of FIG. 23, when the area of ​​the first near-infrared absorption layer 4 is photographed with a near-infrared camera, near-infrared light is absorbed not only by the first near-infrared absorption layer 4 but also by the second near-infrared absorption layer 6 located thereunder, and therefore a near-infrared image that is actually darker than when the first near-infrared absorption layer 4 is photographed alone is obtained (the same applies to the area of ​​the first near-infrared absorption layer 4 in the surface view of FIG. 25 described later).

[0048] The laminate 1 of the fifth embodiment includes a second near-infrared absorbing layer 6 between the substrate layer 2 and the (first) near-infrared absorbing layer 4. The substrate layer 2 may be a transparent sheet similar to that of the second embodiment, or a paper substrate, and the first near-infrared absorbing layer 4 is a layer formed using a near-infrared absorbing ink containing one or both of cesium tungsten oxide and lanthanum hexaboride similar to that of the second embodiment, but the second near-infrared absorbing layer 6 is a near-infrared absorbing layer containing a near-infrared absorbing material different from cesium tungsten oxide and lanthanum hexaboride.

[0049] In one example, the second near-infrared absorbing layer 6 contains one or more of near-infrared absorbing materials whose near-infrared absorption effect is not significantly affected even when irradiated with a near-infrared laser, such as antimony tin oxide (ATO), indium tin oxide (ITO), and copper pyrophosphate (Cu2P2O7), and the second near-infrared absorbing layer 6 can be formed by printing on the substrate layer 2 using a near-infrared absorbing ink containing such a near-infrared absorbing material, or by applying such a near-infrared absorbing ink to the substrate layer 2. The near-infrared absorbing ink used for the second near-infrared absorbing layer 6 contains a dispersant, a monomer, a synthetic resin, an auxiliary, and the like, in addition to a near-infrared absorbing material (powder, etc.) such as antimony tin oxide, indium tin oxide, and copper pyrophosphate. The content of antimony tin oxide in the antimony tin oxide-containing ink is arbitrary, but in one example, the content may be 0.5% by weight (weight percent) to 6% by weight. The content of indium tin oxide in the indium tin oxide-containing ink is arbitrary, but may be 0.5% by weight (weight percent) to 6% by weight in one example. The content of copper pyrophosphate in the copper pyrophosphate-containing ink is arbitrary, but may be 0.5% by weight (weight percent) to 6% by weight in one example. Even when using a near-infrared absorbing ink containing two or more of antimony tin oxide, indium tin oxide, and copper pyrophosphate, the respective contents of antimony tin oxide, indium tin oxide, and copper pyrophosphate are similarly arbitrary. In either case, the preferred content can be changed depending on the printing density (amount) and the like. Note that the "content (weight percent) of antimony tin oxide" referred to here is the ratio of the weight of antimony tin oxide contained in the ink to the total weight of the ink, Content of antimony tin oxide in ink (% by weight) = {(weight of antimony tin oxide) / (total weight of ink)} x 100 It is expressed by: Similarly, "content of indium tin oxide (wt%)" is the weight ratio of indium tin oxide contained in the ink to the total weight of the ink, Indium tin oxide content in ink (wt%) = {(weight of indium tin oxide) / (total weight of ink)} x 100 It is expressed by: Similarly, "copper pyrophosphate content (wt%)" is the weight ratio of copper pyrophosphate contained in the ink to the total weight of the ink, Content of copper pyrophosphate in ink (% by weight) = {(weight of copper pyrophosphate) / (total weight of ink)} x 100 It is expressed by:

[0050] The laminate 1 shown in FIG. 20 etc. can be produced by printing on the base layer 2 using a near-infrared absorbing ink containing the above-mentioned antimony tin oxide, indium tin oxide, copper pyrophosphate, etc., or by applying such a near-infrared absorbing ink on the base layer 2 to form a second near-infrared absorbing layer 6, and printing on the second near-infrared absorbing layer 6 using a near-infrared absorbing ink containing one or both of cesium tungsten oxide and lanthanum hexaboride, or by applying such a near-infrared absorbing ink on the second near-infrared absorbing layer 6 to form a first near-infrared absorbing layer 4.

[0051] Fig. 24 is a diagram (near-infrared image, cross-sectional view) showing that the near-infrared absorbency of the part of the laminate where the laser light hit is reduced by irradiating the laminate shown in Fig. 20 etc. with laser light in the direction of the arrow L, and Fig. 25 is a diagram (near-infrared image, surface view) showing an observation image of the surface when the laminate is irradiated with laser light as shown in Fig. 24 and instruction information is written on the laminate. The first near-infrared absorption layer 4 containing cesium tungsten oxide or lanthanum hexaboride has a property that the near-infrared absorbency is reduced by being irradiated with near-infrared laser light, so that, for example, by performing laser marking on the near-infrared absorption layer 4 so as to draw marker information or two-dimensional code information, it is possible to write information that is at least difficult to recognize with a visible light camera or the naked eye but can be recognized by a near-infrared camera. When the base layer 2 is a base layer having near-infrared transmittance, such as a transparent base material, and the second near-infrared absorption layer 6 transmits at least a part of near-infrared rays, laser marking may be performed by irradiating the first near-infrared absorption layer 4 with laser light from the base layer 2 side, not from the direction of arrow L in FIG. 20 (from the side of the first near-infrared absorption layer 4 in the laminate 1).

[0052] Sixth embodiment FIG. 26 is a diagram showing an observation image (visible light image) of a cross section of a laminate in the sixth embodiment of the present invention under visible light (the surface view is the same as FIG. 22, but the reference number "6" is replaced with the reference number "2"). FIG. 27 is a diagram showing an observation image (near-infrared image) of a cross section of the laminate taken with a near-infrared camera (the surface view is the same as FIG. 23, but the reference number "6" is replaced with the reference number "2" and the oblique lines in that portion indicate the second near-infrared absorption layer 6 under the base layer 2). FIG. 28 is a diagram (near-infrared image, cross section) showing that the laminate is irradiated with laser light in the direction of arrow L, and the near-infrared absorbency of the portion of the laminate where the laser light hit is reduced (the surface view is the same as FIG. 25, but the reference number "6" is replaced with the reference number "2" and the oblique lines in that portion indicate the second near-infrared absorption layer 6 under the base layer 2).

[0053] In the laminate 1 of the sixth embodiment, the order of lamination of the base material layer 2 and the second near-infrared absorbing layer 6 is reversed compared to the laminate 1 of the fifth embodiment, but the other configurations may be the same as those of the fifth embodiment, and by performing laser marking on the first near-infrared absorbing layer 4 as shown in Fig. 28, information that is at least difficult to recognize with a visible light camera or the naked eye but can be recognized by a near-infrared camera can be written. When the base material layer 2 is a base material layer having near-infrared transmittance such as a transparent base material and the second near-infrared absorbing layer 6 transmits near-infrared rays at least in part, the laser marking may be performed by irradiating the first near-infrared absorbing layer 4 with laser light from the side of the second near-infrared absorbing layer 6, not in the direction of the arrow L in Fig. 28 (from the side of the first near-infrared absorbing layer 4 in the laminate 1). The laminate 1 shown in FIG. 26 etc. can be produced by printing on the base layer 2 using a near-infrared absorbing ink containing the above-mentioned antimony tin oxide, indium tin oxide, copper pyrophosphate, or the like, or by applying such a near-infrared absorbing ink onto the base layer 2 to form a second near-infrared absorbing layer 6, and printing on the surface of the base layer 2 opposite to the surface on which the second near-infrared absorbing layer 6 is formed using a near-infrared absorbing ink containing one or both of cesium tungsten oxide and lanthanum hexaboride, or by applying such a near-infrared absorbing ink to the surface of the base layer 2 opposite to the surface on which the second near-infrared absorbing layer 6 is formed to form the first near-infrared absorbing layer 4.

[0054] Seventh embodiment FIG. 29 is a diagram showing an observation image (visible light image) of a cross section (A-A' cross section cut along line A-A' in FIG. 31, etc.; similar to other figures) of a laminate in the seventh embodiment of the present invention, taken under visible light; FIG. 30 is a diagram showing an observation image (near-infrared image) of a cross section of the laminate, taken with a near-infrared camera; FIG. 31 is a diagram showing an observation image (visible light image) of the surface of the laminate, taken under visible light (surface visible in the direction of arrow L in FIG. 29; similar to other figures); and FIG. 32 is a diagram showing an observation image (near-infrared image) of the surface of the laminate, taken with a near-infrared camera.

[0055] In the laminate 1 of the seventh embodiment, the near-infrared absorbing layer on the substrate layer 2 (which may be a transparent sheet similar to that in the second embodiment, or a paper substrate, etc.) is divided into two regions, a first near-infrared absorbing region 7 and a second near-infrared absorbing region 8. The first near-infrared absorbing region 7 is formed as a layer containing a near-infrared absorbing ink composition containing one or both of cesium tungsten oxide and lanthanum hexaboride, similar to the near-infrared absorbing layer 4 in the second embodiment, and the near-infrared absorbency is reduced by irradiation with near-infrared laser light. The second near-infrared absorbing region 8 is formed as a layer containing one or more near-infrared absorbing materials whose near-infrared absorption effect is not significantly affected by irradiation with a near-infrared laser, such as antimony tin oxide, indium tin oxide, and copper pyrophosphate, which are different from cesium tungsten oxide and lanthanum hexaboride, similar to the second near-infrared absorbing layer 6 in the fifth embodiment. The laminate 1 shown in FIG. 29 etc. can be produced by printing a portion of the base layer 2 corresponding to the first near-infrared absorbing region 7 using a near-infrared absorbing ink containing one or both of the above-mentioned cesium tungsten oxide and lanthanum hexaboride, or by applying such a near-infrared absorbing ink to form the first near-infrared absorbing region 7 of the near-infrared absorbing layer, and printing a portion of the base layer 2 corresponding to the second near-infrared absorbing region 8 using a near-infrared absorbing ink containing the above-mentioned antimony tin oxide, indium tin oxide, copper pyrophosphate, etc., or by applying such a near-infrared absorbing ink to form the second near-infrared absorbing region 8 of the near-infrared absorbing layer.

[0056] FIG. 33 is a diagram (near-infrared image, cross-sectional view) showing that the near-infrared absorbency of the part of the laminate where the laser light hits is reduced when the laminate shown in FIG. 29 etc. is irradiated with laser light in the direction of the arrow L, and FIG. 34 is a diagram (near-infrared image, surface view) showing an observation image of the surface when the medium is irradiated with laser light as shown in FIG. 33 and instruction information is written on the medium. When the base layer 2 is a base layer having near-infrared transmittance such as a transparent base material, laser marking may be performed by irradiating the first near-infrared absorbing region 7 with laser light from the side of the base layer 2, not in the direction of the arrow L in FIG. 33 (from the side of the near-infrared absorbing layer in the laminate 1). Even when the laser light is irradiated, information that is at least difficult to recognize with a visible light camera or the naked eye but can be recognized by a near-infrared camera can be written.

[0057] Eighth embodiment FIG. 35 is a diagram showing an observation image (visible light image) of a cross section of a laminate in the eighth embodiment of the present invention under visible light (the surface view is the same as FIG. 3, but the reference number "2" is replaced with the reference number "4"), FIG. 36 is a diagram showing an observation image (near-infrared image) of a cross section of the laminate taken with a near-infrared camera (the surface view is the same as FIG. 4, but the reference number "2" is replaced with the reference number "4"), and FIG. 37 is a diagram (near-infrared image, cross-sectional view) showing that the near-infrared absorbency of the portion of the laminate hit by the laser light is reduced when the laminate shown in FIG. 35 etc. is irradiated with laser light in the direction of arrow L (the surface view is the same as FIGS. 6 to 7, but the reference number "2" is replaced with the reference number "4").

[0058] In the laminate 1 of the eighth embodiment, a near-infrared reflective layer 9 is formed on a base layer 2 (which may be a transparent sheet similar to that in the second embodiment, or a paper base material, etc.), and a near-infrared absorbing layer 4 (which is a layer similar to the near-infrared absorbing layer 4 in the second embodiment and contains one or both of cesium tungsten oxide and lanthanum hexaboride) is formed on the near-infrared reflective layer 9.

[0059] In one example, the near-infrared reflective layer 9 contains one or more of near-infrared reflective materials having near-infrared reflectivity, such as titanium oxide (titanium oxide (IV): TiO2), silicon oxide (SiO2), and tin oxide (tin oxide (IV): SnO2), and the near-infrared reflective layer 9 can be formed by printing on the substrate layer 2 using a near-infrared reflective ink containing such a near-infrared reflective material, or by applying such a near-infrared reflective ink to the substrate layer 2. The near-infrared reflective ink used for the near-infrared reflective layer 9 contains a dispersant, a monomer, a synthetic resin, an auxiliary, and the like, in addition to a near-infrared reflective material (powder, etc.) such as titanium oxide, silicon oxide, and tin oxide. The content of titanium oxide in the titanium oxide-containing ink is arbitrary, but in one example, it may be a content of 0.5% by weight (weight percent) to 30% by weight. The content of silicon oxide in the silicon oxide-containing ink is arbitrary, but in one example, it may be a content of 0.5% by weight (weight percent) to 30% by weight. The content of tin oxide in the tin oxide-containing ink is arbitrary, but in one example, the content may be 0.5% by weight (weight percent) to 30% by weight. When using a near-infrared reflective ink containing two or more of titanium oxide, silicon oxide, and tin oxide, the respective contents of titanium oxide, silicon oxide, and tin oxide are similarly arbitrary. In either case, the preferred content can be changed depending on the printing density (amount applied), etc. Note that the "titanium oxide content (weight %)" referred to here is the ratio of the weight of titanium oxide contained in the ink to the total weight of the ink, Titanium oxide content in ink (% by weight) = {(titanium oxide weight) / (total ink weight)} x 100 It is expressed by: Similarly, "silicon oxide content (wt%)" is the weight ratio of silicon oxide contained in the ink to the total weight of the ink, Silicon oxide content in ink (% by weight) = {(weight of silicon oxide) / (total weight of ink)} x 100 It is expressed by: Similarly, "tin oxide content (wt%)" is the percentage by weight of tin oxide contained in the ink relative to the total weight of the ink. Content of tin oxide in ink (% by weight) = {(weight of tin oxide) / (total weight of ink)} x 100 It should be noted that the near-infrared reflective layer 9 in Fig. 35 etc. may be colored (visible light absorbing) or colorless (visible light transmissive) (the same applies to other figures).

[0060] The laminate 1 shown in FIG. 35 etc. can be produced by printing on a base layer 2 using a near-infrared reflective ink containing the above-mentioned titanium oxide, silicon oxide, tin oxide, etc., or by applying such a near-infrared reflective ink onto the base layer 2 to form a near-infrared reflective layer 9, and printing on the near-infrared reflective layer 9 using a near-infrared absorbing ink containing one or both of cesium tungsten oxide and lanthanum hexaboride, or by applying such a near-infrared absorbing ink onto the near-infrared reflective layer 9 to form a near-infrared absorbing layer 4.

[0061] As in the second embodiment and the like, the near-infrared absorbing layer 4 containing cesium tungsten oxide or lanthanum hexaboride has a property of decreasing near-infrared absorbency when irradiated with near-infrared laser light. Therefore, by performing laser marking on the near-infrared absorbing layer 4 so as to depict, for example, marker information such as an ArUco marker or two-dimensional code information such as a QR code (registered trademark) (since the near-infrared reflective layer 9 is present, it is preferable to irradiate with near-infrared laser light from the side of the near-infrared absorbing layer 4 in the laminate 1 as shown by arrow L in FIG. 36), it is possible to write information that is at least difficult to recognize with a visible light camera or the naked eye but can be recognized by a near-infrared camera.

[0062] Ninth embodiment FIG. 38 is a diagram showing an observation image (visible light image) of a cross section of a laminate in the ninth embodiment of the present invention under visible light (the surface view is the same as FIG. 3, but the reference number "2" is replaced with the reference number "4"), FIG. 39 is a diagram showing an observation image (near-infrared image) of a cross section of the laminate taken with a near-infrared camera (the surface view is the same as FIG. 4, but the reference number "2" is replaced with the reference number "4"), and FIG. 40 is a diagram (near-infrared image, cross-sectional view) showing that the near-infrared absorbency of the portion of the laminate hit by the laser light is reduced when the laminate shown in FIG. 38 etc. is irradiated with laser light in the direction of arrow L (the surface view is the same as FIGS. 6 to 7, but the reference number "2" is replaced with the reference number "4").

[0063] In the laminate 1 of the ninth embodiment, the order of lamination of the base material layer 2 and the near-infrared reflective layer 9 is reversed compared to the laminate 1 of the eighth embodiment, but the other configuration may be the same as that of the eighth embodiment. As shown in FIG. 40, by performing laser marking on the near-infrared absorbing layer 4, it is possible to write information (instruction information for a moving body; the same applies to other embodiments) that is at least difficult to recognize with a visible light camera or the naked eye but can be recognized by a near-infrared camera (due to the presence of the near-infrared reflective layer 9, it is preferable to irradiate the near-infrared laser light from the side of the near-infrared absorbing layer 4 in the laminate 1, as shown by arrow L in FIG. 40). The laminate 1 shown in FIG. 38 etc. can be produced by printing on the base layer 2 using a near-infrared reflective ink containing the above-mentioned titanium oxide, silicon oxide, tin oxide, etc., or by applying such a near-infrared reflective ink onto the base layer 2 to form a near-infrared reflective layer 9, and printing on the surface of the base layer 2 opposite to the surface on which the near-infrared reflective layer 9 is formed using a near-infrared absorbing ink containing one or both of cesium tungsten oxide and lanthanum hexaboride, or by applying such a near-infrared absorbing ink to the surface of the base layer 2 opposite to the surface on which the near-infrared reflective layer 9 is formed to form the near-infrared absorbing layer 4.

[0064] Tenth embodiment FIG. 41 is a diagram showing a cross-section observation image (visible light image) of the laminate in the tenth embodiment of the present invention under visible light (the surface view is the same as FIG. 3, but the reference number "2" is replaced with the reference number "10"). FIG. 42 is a diagram showing a cross-section observation image (near-infrared image) of the laminate by a near-infrared camera (the surface view is the same as FIG. 4, but the reference number "2" is replaced with the reference number "10", and the oblique lines in that part indicate the near-infrared absorbing layer 4 under the abrasion-resistant hard coat layer 10). FIG. 43 is a diagram (near-infrared image, cross-sectional view) showing that the laser light is irradiated to the laminate shown in FIG. 41 etc. in the direction of the arrow L, and the near-infrared absorbency of the part of the laminate where the laser light hit is reduced (the surface view is the same as FIG. 6 to FIG. 7, but the reference number "2" is replaced with the reference number "10", and the oblique lines in that part indicate the near-infrared absorbing layer 4 under the abrasion-resistant hard coat layer 10).

[0065] The laminate 1 of the tenth embodiment includes, from the top in the plane of FIG. 41, an abrasion-resistant hard coat layer 10, a near-infrared absorbing layer 4, a near-infrared reflective layer 9, a substrate layer 2, an adhesive layer 11, and a release film 12.

[0066] The abrasion-resistant hard coat layer 10 (having visible light transmittance and near-infrared transmittance) is, in one example, a layer with excellent resistance to abrasion formed by applying an acrylic resin. The near-infrared absorbing layer 4 is a layer formed using a near-infrared absorbing ink containing one or both of cesium tungsten oxide and lanthanum hexaboride, as in the second embodiment. The near-infrared reflective layer 9 is a layer containing a near-infrared reflective material such as titanium oxide, silicon oxide, or tin oxide, as in the eighth embodiment. The substrate layer 2 is formed as a transparent substrate such as a transparent sheet having visible light transmittance and near-infrared transmittance, or any non-transparent substrate, as in the second embodiment. The adhesive layer 11 is formed, in one example, as described in paragraph

[0046] of Patent Document 15, by an adhesive using a mixture of an elastomer such as natural rubber, reclaimed rubber, or SBR, and a low or medium molecular weight tackifier, an antioxidant, etc. in a solution state. In the case of a thermoplastic elastomer, application in a molten state is possible. When resistance to light and oxidation is required, materials such as acrylate copolymers and polyisobutylene can be used. A hot-melt type heat sealant may also be used. As described in paragraphs

[0072] -

[0073] of Patent Document 16, for example, the release film 12 can be prepared by applying a release agent such as a water-soluble resin, a hydrophilic resin, a wax, a silicone resin, a fluororesin, an aminoalkyd resin, a melamine resin, a polyester resin, or an acrylic resin to a film using a polyester resin or a polycarbonate resin. Examples of polyester resins include polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polybutylene naphthalate, polyarylate, and polytetramethylene terephthalate. In particular, polyethylene terephthalate is preferable from the viewpoints of ease of handling, cost, and the like. In one example, after peeling off the release film 12 from the laminate 1, the adhesive layer 11 of the laminate 1 (a laminate 1 not including the release film 12 is also called "laminate 1") is attached to a wall, ceiling, etc., so that the laminate 1 can be attached to an indoor surface. The abrasion-resistant hard coat layer 10 has the effect of preventing scratches, but is not necessarily required.

[0067] In the laminate 1 of the tenth embodiment, similarly to the laminate 1 of the second embodiment, etc., by performing laser marking on the near-infrared absorbing layer 4, information that is at least difficult to recognize with a visible light camera or the naked eye but can be recognized by a near-infrared camera can be written (because of the presence of the near-infrared reflective layer 9, it is preferable to irradiate the near-infrared laser light from the side of the abrasion-resistant hard coat layer 10 in the laminate 1 as shown by the arrow L in FIG. 43). In one example, the laminate 1 shown in FIG. 41, etc., is (1) A near-infrared reflective layer 9 is formed on the substrate layer 2 by printing with a near-infrared reflective ink containing the above-mentioned titanium oxide, silicon oxide, tin oxide, or the like, or by coating such a near-infrared reflective ink on the substrate layer 2; (2) forming a near-infrared absorbing layer 4 by applying a near-infrared absorbing ink containing one or both of cesium tungsten oxide and lanthanum hexaboride onto the near-infrared reflective layer 9 or by printing on the near-infrared reflective layer 9 using such a near-infrared absorbing ink; (3) An abrasion-resistant resin is applied to the surface of the near-infrared absorbing layer 4 opposite to the near-infrared reflective layer 9 to form an abrasion-resistant hard coat layer 10; (4) Applying the adhesive material to the surface of the base layer 2 opposite to the surface on which the near-infrared reflective layer 9 is formed to form an adhesive layer 11; (5) The release film 12 is attached to the surface of the adhesive layer 11 opposite to the base layer 2. It can be produced in this way.

[0068] Eleventh embodiment Next, a system for controlling the operation of a moving object such as a vehicle indoors will be described as a specific example of a system for acquiring information by capturing an image of the information display medium 1 in each of the above-mentioned embodiments with a near-infrared camera.

[0069] FIG. 44 is a diagram for explaining that information display media are attached to indoor walls, and a moving body (vehicle) reads instruction information printed on each information display medium and moves autonomously. Information display media A1 to D1, on which instruction information for the moving body is written by laser marking, are attached to indoor walls 13 to 15 by adhesive or the like, as the information display medium 1 of any of the above-mentioned embodiments. A moving body 17 such as a vehicle first photographs the information display medium A1 with a near-infrared camera 19, reads the instruction information from the photographed image, and performs an action such as moving according to the instruction information, and then sequentially reads the information display media B1 to D1 and performs an action according to the instruction information written on each information display medium. At this time, the appearance of the information display media A1 to D1 is in a state that is at least difficult to recognize with a visible light camera or the naked eye, but can be recognized by a near-infrared camera. The size of the instruction information, which is the laser-marked area on the information display media A1-D1, is not limited, but in the case of a square shape, the length of one side is preferably 5 cm, more preferably the length of one side of the square shape may be 10 cm, or the length of one side of the square shape may be 20 cm. Although the shape of the instruction information is exemplified as a square, the shape can be changed as appropriate, such as a rectangle, a diamond, or a trapezoid.

[0070] Figure 45 is a block diagram showing the functional configuration of a moving body (vehicle), Figure 46 is a block diagram showing the functional configuration of an operation control unit of the moving body (vehicle), and Figure 47 is a block diagram showing the device configuration of a near-infrared camera (near-infrared imaging unit) mounted on the moving body.

[0071] The mobile body 17 includes a mobile body main body 18, a near-infrared camera 19, wheels 20 to 23, and a distance sensor unit 24, and the mobile body main body 18 includes a motion control unit 25, a power transmission mechanism, a direction control mechanism, etc. 26, a communication unit 27, and a power supply system 28. The near-infrared camera 19 is a near-infrared camera that captures near-infrared moving or still images and has a configuration as shown in Fig. 47, and includes an infrared camera lens 32, a sensor unit 33, a memory 34, a processing circuit 35, a communication unit 36 ​​communicatively connected to the motion control unit 25 by a cable 37, and a power supply system 38.

[0072] The infrared camera lens 32 is a lens that can refract at least near-infrared light and guide it to the infrared sensor unit 33. The infrared sensor unit 33 may be a thermal infrared sensor such as a bolometer type, a quantum infrared sensor such as an InGaAs type, or another type of infrared sensor, and may also include a cooler or the like as necessary. The memory 34 is a memory device such as a RAM (Random Access Memory), and if the captured video and images are to be stored in the near-infrared camera 19, a memory card such as a flash memory, a hard disk, an SSD (Solid State Drive), or the like may also be appropriately provided. The processing circuit 35 is a processing circuit including an A / D (analog / digital) converter that converts the near-infrared image detected by the infrared sensor unit 33 from analog information to digital data, a processor that performs various data processing, and the like. The communication unit 36 ​​includes a communication circuit (and a communication antenna as necessary in the case of wireless communication, etc.) that transmits the digital data (stored (recorded) in the memory 34 as appropriate) obtained by the conversion by the A / D converter of the processing circuit 35 to the operation control unit 25 through a cable 37, for example. The power supply system 38 includes a battery such as a lithium ion battery, and a circuit for supplying power to the processing circuit 35, etc. The near-infrared camera 19 also includes various other elements such as buttons, but since the near-infrared camera itself is well known, a further detailed description will not be given (as for other devices, etc., descriptions of well-known and well-known elements will be omitted as appropriate).

[0073] The wheels 20-23 rotate and change direction under the control of a power transmission mechanism, direction control mechanism, etc. (including various control mechanisms such as a motor, an ESC (Electric Speed ​​Controller), and a mechanism for direction control) 26, which are controlled by control signals from a motion control unit 25, to move the moving body 17 forward or backward or to change the direction of the moving body 17 by turning, etc. The distance sensor unit 24 includes distance sensors such as a laser distance sensor and an ultrasonic sensor, and transmits a signal indicating the distance between the moving body 17 and an obstacle or the like ahead to the motion control unit 25. The motion control unit 25 includes a processing circuit and the like that controls the motion of the moving body 17 by transmitting control signals to the power transmission mechanism, direction control mechanism, etc. 26. The operation control unit 25 includes an ASIC (application specific integrated circuit), an embedded system, a microcomputer, or a CPU (Central Processing Unit), and processes data such as captured image data received from the near-infrared camera 19, data indicating the distance to an obstacle, etc., received from the distance sensor unit 24, and command signals received from the outside via a communication unit 27 (including a communication circuit, a communication antenna, etc.) (the operation of the moving body 17 may be controlled by a control signal from the outside, or it may move completely autonomously under the control of the operation control unit 25). The operation control unit 25 includes a memory device such as a RAM, and also includes a hard disk, an SSD, etc. as necessary. The power supply system 28 includes a battery such as a lithium ion battery, and a circuit for supplying power to the operation control unit 25, the power transmission mechanism, the orientation control mechanism 26, etc.

[0074] 46, the operation control unit 25 includes an image processing unit 29, a code information processing unit 30, and a control signal generating unit 31. In one example, the operation control unit 25 includes a CPU and a storage device, and the CPU executes an image processing program stored in the storage device to cause the operation control unit 25 to function as the image processing unit 29, the CPU executes a code information processing program stored in the storage device to cause the operation control unit 25 to function as the code information processing unit 30, and the CPU executes a control signal generating program stored in the storage device to cause the operation control unit 25 to function as the control signal generating unit 31. The operation control unit 25 further includes a D / A converter (Digital-to-Analog Converter) as necessary, and converts a control signal as a digital signal into an analog signal and transmits it to the power transmission mechanism, the direction control mechanism, etc. 26.

[0075] The image processing unit 29 processes the captured image data of the near-infrared camera received from the near-infrared camera 19, performs keystone correction on the near-infrared image of the information display medium 1 in the near-infrared image, and extracts marker information, two-dimensional code information, etc. from the keystone corrected near-infrared image of the information display medium 1. The code information processing unit 30 processes the extracted marker information, two-dimensional code information, etc., and reads instruction information for the moving object 17 from the extracted information. In one example, the marker information is information indicating an ID (Identification) number such as "ID=1" or "ID=2" converted into a pattern shown in FIG. 6, etc., and the code information processing unit converts the pattern shown in FIG. 6, etc. into a corresponding ID number, and then reads instruction information for the moving object 17 as information instructing a specific operation corresponding to the obtained ID number. In this case, the code information processing program includes a program for converting the pattern information shown in FIG. 6 and the like into an ID number, and a program for identifying specific operation instruction information from the obtained ID number, and the storage device of the operation control unit 25 stores data in a form such as a database, such as a table format showing the correspondence between the patterns shown in FIG. 6 and the ID number, and data in a form such as a table showing the correspondence between each ID number and each specific operation. If the information extracted from the near-infrared image is two-dimensional code information, the code information processing unit 30 decodes the two-dimensional code information and reads specific operation instruction information for the moving object 17. In this case, the code information processing program includes a program for decoding the two-dimensional code information shown in FIG. 7 and the like into specific operation instruction information, and data required for decoding is also stored in the storage device of the operation control unit 25. The control signal generating unit 31 generates a control signal indicating specific operation instruction information for the moving object 17 identified by the code information processing unit 30, converts the digital signal to an analog signal by a D / A converter as necessary, and transmits it to the power transmission mechanism, orientation control mechanism, etc. 26. The control signal generating unit 31 also generates control signals for controlling marker search operations such as turning and various other operations, and if necessary, converts them from digital to analog signals using a D / A converter before transmitting them to the power transmission mechanism, orientation control mechanism, etc. 26.

[0076] 48 and 49 are flow charts of a control operation for controlling the operation of a moving body (vehicle) by reading information written on an information display medium by photographing the information display medium attached to a wall with a near-infrared camera. First, moving body 17 searches for a marker by turning or the like under the control of control signal generator 31 (step S101). At this time, near-infrared camera 19 continues to photograph the area diagonally upward in front as a video (see FIG. 44. In the examples of FIGS. 48 to 49 and 51 to 52, it is assumed that near-infrared camera 19 is always photographing video). If the near-infrared camera 19 can recognize information display medium A1 (hereinafter referred to as marker A1; the same applies to information display media B1-D1, A2-D2. Note that in the examples of Figures 48-49 and Figures 51-52, it is not necessary to read in the order of markers A1-D1 or markers A2-D2, and the moving body 17 may be operated by reading in the order of the markers that have been recognized) (the image processing unit 29 can extract marker A1 from the image captured by the near-infrared camera 19) ("Yes" in step S102), the moving body 17 approaches marker A1 so as to capture an image of marker A1 from the front, under the control of the control signal generating unit 31 using the distance signal transmitted from the distance sensor unit 24 to the operation control unit 25, and then operates as instructed by marker A1 (step S103). Specifically, as described above, the image processing unit 29 extracts marker information (it may be information in any other format, such as two-dimensional code information. It will be omitted below) from the near-infrared image captured by the near-infrared camera 19, and the code information processing unit 30 processes the extracted marker information as described above to read instruction information for the moving body 17. In the current example, the instruction information for the moving body 17 written in the marker A1 is "information instructing to turn 90 degrees to the right", and the code information processing unit 30 reads this instruction information, and the control signal generating unit 31 generates a control signal indicating this instruction information and transmits it to the power transmission mechanism, direction control mechanism, etc. 26, and the power transmission mechanism, direction control mechanism, etc. 26 controls the operation of the wheels 20 to 23, and the moving body 17 turns 90 degrees to the right. On the other hand, if the near-infrared camera 19 cannot recognize the marker A1 ("No" in step S102), the process returns to step S101, and the moving body 17 searches for the marker again.

[0077] After the moving body 17 turns 90° to the right in step S103, the moving body 17 searches for the marker by turning or the like under the control of the control signal generating unit 31 in step S104. If the near-infrared camera 19 can recognize the marker B1 (the image processing unit 29 can extract the marker B1 from the image captured by the near-infrared camera 19) ("Yes" in step S105), the moving body 17 approaches the marker B1 so as to capture the marker B1 from the front while receiving the control of the control signal generating unit 31 using the distance signal transmitted from the distance sensor unit 24 to the operation control unit 25, and then operates according to the instruction of the marker B1 (step S106). Specifically, as described above, the image processing unit 29 extracts marker information from the near-infrared image captured by the near-infrared camera 19, and the code information processing unit 30 processes the extracted marker information as described above to read instruction information for the moving body 17. In the current example, the instruction information for the moving object 17 written in the marker B1 is "information instructing the moving object 17 to turn 90° to the right and move forward a predetermined distance", and this instruction information is read by the code information processing unit 30, and the control signal generating unit 31 generates a control signal indicating this instruction information and transmits it to the power transmission mechanism, direction control mechanism, etc. 26, which controls the operation of the wheels 20 to 23, causing the moving object 17 to turn 90° to the right and move forward a predetermined distance. On the other hand, if the near-infrared camera 19 cannot recognize the marker B1 ("No" in step S105), the process returns to step S104, and the moving object 17 searches for the marker again.

[0078] In step S106, the moving body 17 turns 90° to the right and moves forward a predetermined distance, and then in step S107, the moving body 17 turns or the like under the control of the control signal generating unit 31 to search for the marker. If the near-infrared camera 19 can recognize the marker C1 (the image processing unit 29 can extract the marker C1 from the image captured by the near-infrared camera 19) ("Yes" in step S108), the moving body 17 approaches the marker C1 so as to capture the marker C1 from the front while receiving the control of the control signal generating unit 31 using the distance signal transmitted from the distance sensor unit 24 to the operation control unit 25, and then operates according to the instruction of the marker C1 (step S109). Specifically, as described above, the image processing unit 29 extracts marker information from the near-infrared image captured by the near-infrared camera 19, and the code information processing unit 30 processes the extracted marker information as described above to read instruction information for the moving body 17. In the current example, the instruction information for the moving object 17 written in the marker C1 is "information instructing the moving object 17 to turn 90° to the left", and this instruction information is read by the code information processing unit 30, and the control signal generating unit 31 generates a control signal indicating this instruction information and transmits it to the power transmission mechanism, direction control mechanism, etc. 26, which then controls the operation of the wheels 20 to 23, causing the moving object 17 to turn 90° to the left. On the other hand, if the near-infrared camera 19 cannot recognize the marker C1 ("No" in step S108), the process returns to step S107, and the moving object 17 searches for the marker again.

[0079] After the moving body 17 turns 90° to the left in step S109, the moving body 17 searches for the marker by turning or the like under the control of the control signal generating unit 31 in step S110. If the near-infrared camera 19 can recognize the marker D1 (the image processing unit 29 can extract the marker D1 from the image captured by the near-infrared camera 19) ("Yes" in step S111), the moving body 17 approaches the marker D1 so as to capture the marker D1 from the front while receiving the control of the control signal generating unit 31 using the distance signal transmitted from the distance sensor unit 24 to the operation control unit 25, and then operates according to the instruction of the marker D1 (step S112). Specifically, as described above, the image processing unit 29 extracts marker information from the near-infrared image captured by the near-infrared camera 19, and the code information processing unit 30 processes the extracted marker information as described above to read instruction information for the moving body 17. In the current example, the instruction information for the moving object 17 written in the marker D1 is "information instructing the moving object 17 to retreat a predetermined distance and stop", and this instruction information is read by the code information processing unit 30, and the control signal generating unit 31 generates a control signal indicating this instruction information and transmits it to the power transmission mechanism, direction control mechanism, etc. 26, which then controls the operation of the wheels 20 to 23, causing the moving object 17 to retreat a predetermined distance and stop. On the other hand, if the near-infrared camera 19 cannot recognize the marker D1 ("No" in step S111), the process returns to step S110, and the moving object 17 searches for the marker again.

[0080] FIG. 50 is a diagram for explaining that information display media are attached to an indoor ceiling, and a moving body (vehicle) moves autonomously by reading instruction information printed on each information display media. The information display media may be attached to any location, such as a wall, ceiling, or floor. Also, FIG. 51 and FIG. 52 are flow charts of a control operation for controlling the operation of a moving body (vehicle) by reading information written on the information display media by photographing the information display media attached to the ceiling with a near-infrared camera. When the information display media (here, markers A2 to D2) are attached to the ceiling, as shown in FIG. 50, the lens 32 of the near-infrared camera 19 is directed upwards, or a wide-angle lens is used so that the ceiling surface can be photographed.

[0081] In step S201, the moving object 17 searches for a marker by turning or the like under the control of the control signal generating unit 31. At this time, the near-infrared camera 19 continues to capture an image in the upward direction as a video (see FIG. 50). If the near-infrared camera 19 can recognize the marker A2 (the image processing unit 29 can extract the marker A2 from the image captured by the near-infrared camera 19) ("Yes" in step S202), the moving object 17 adjusts its position so that the marker A2 can be captured from the front under the control of the control signal generating unit 31, and then operates according to the instruction of the marker A2 (step S203). Specifically, as described above, the image processing unit 29 extracts marker information from the near-infrared image captured by the near-infrared camera 19, and the code information processing unit 30 processes the extracted marker information as described above to read instruction information for the moving object 17. In the current example, the instruction information for the moving object 17 written in the marker A2 is "information instructing the moving object 17 to move a predetermined distance diagonally forward to the right as seen from the moving object 17, which is the direction of the next marker", and this instruction information is read by the code information processing unit 30, and the control signal generating unit 31 generates a control signal indicating this instruction information and transmits it to the power transmission mechanism, direction control mechanism, etc. 26, which controls the operation of the wheels 20 to 23, and the moving object 17 moves a predetermined distance diagonally forward to the right. On the other hand, if the near-infrared camera 19 cannot recognize the marker A2 ("No" in step S202), the process returns to step S201, and the moving object 17 searches for a marker again.

[0082] In step S203, the moving body 17 moves a predetermined distance diagonally forward to the right, and then in step S204, the moving body 17 searches for a marker by turning or the like under the control of the control signal generating unit 31. If the near-infrared camera 19 can recognize the marker B2 (the image processing unit 29 can extract the marker B2 from the image captured by the near-infrared camera 19) ("Yes" in step S205), the moving body 17 adjusts its position so that the marker B2 can be captured from the front under the control of the control signal generating unit 31, and then operates according to the instruction of the marker B2 (step S206). Specifically, as described above, the image processing unit 29 extracts marker information from the near-infrared image captured by the near-infrared camera 19, and the code information processing unit 30 processes the extracted marker information as described above to read instruction information for the moving body 17. In the current example, the instruction information for the moving object 17 written in the marker B2 is "information instructing the moving object 17 to move a predetermined distance diagonally forward and left as seen from the moving object 17, which is the direction of the next marker", and this instruction information is read by the code information processing unit 30, and the control signal generating unit 31 generates a control signal indicating this instruction information and transmits it to the power transmission mechanism, direction control mechanism, etc. 26, which controls the operation of the wheels 20 to 23, and the moving object 17 moves a predetermined distance diagonally forward and left. On the other hand, if the near-infrared camera 19 cannot recognize the marker B2 ("No" in step S205), the process returns to step S204, and the moving object 17 searches for a marker again.

[0083] After the moving body 17 moves a predetermined distance diagonally forward and left in step S206, the moving body 17 searches for the marker by turning or the like under the control of the control signal generating unit 31 in step S207. If the near-infrared camera 19 can recognize the marker C2 (if the image processing unit 29 can extract the marker C2 from the image captured by the near-infrared camera 19) ("Yes" in step S208), the moving body 17 adjusts its position so that the marker C2 can be captured from the front under the control of the control signal generating unit 31, and then operates according to the instruction of the marker C2 (step S209). Specifically, as described above, the image processing unit 29 extracts marker information from the near-infrared image captured by the near-infrared camera 19, and the code information processing unit 30 processes the extracted marker information as described above to read instruction information for the moving body 17. In the current example, the instruction information for the moving object 17 written in the marker C2 is "information instructing the moving object 17 to move a predetermined distance diagonally forward to the right as seen from the moving object 17, which is the direction of the next marker", and this instruction information is read by the code information processing unit 30, and the control signal generating unit 31 generates a control signal indicating this instruction information and transmits it to the power transmission mechanism, direction control mechanism, etc. 26, which controls the operation of the wheels 20 to 23, and the moving object 17 moves a predetermined distance diagonally forward to the right. On the other hand, if the near-infrared camera 19 cannot recognize the marker C2 ("No" in step S208), the process returns to step S207, and the moving object 17 searches for a marker again.

[0084] After the moving body 17 moves a predetermined distance diagonally forward to the right in step S209, the moving body 17 searches for a marker by turning or the like under the control of the control signal generating unit 31 in step S210. If the near-infrared camera 19 can recognize the marker D2 (if the image processing unit 29 can extract the marker D2 from the image captured by the near-infrared camera 19) ("Yes" in step S211), the moving body 17 adjusts its position so that the marker D2 can be captured from the front under the control of the control signal generating unit 31, and then operates according to the instruction of the marker D2 (step S212). Specifically, as described above, the image processing unit 29 extracts marker information from the near-infrared image captured by the near-infrared camera 19, and the code information processing unit 30 processes the extracted marker information as described above to read instruction information for the moving body 17. In the current example, the instruction information for the moving object 17 written in the marker D2 is "information instructing the moving object 17 to stop", and this instruction information is read by the code information processing unit 30, and the control signal generating unit 31 generates a control signal indicating this instruction information and transmits it to the power transmission mechanism, direction control mechanism, etc. 26, which then controls the operation of the wheels 20 to 23 to stop the moving object 17. On the other hand, if the near-infrared camera 19 cannot recognize the marker D2 ("No" in step S211), the process returns to step S210, and the moving object 17 searches for the marker again.

[0085] Fig. 53 is a diagram showing a schematic configuration of a laser marker device for performing the laser marking (drawing, printing, etc.) described above. The laser marker device 39 includes a control unit 40, a storage unit 41, a driving (scanning) unit 42, a laser light irradiating unit 43, etc. While the head of the laser light irradiating unit 43 is driven by the driving unit 42, near-infrared laser light is irradiated from the head to the near-infrared absorbing layer or to the laser coloring layer, whereby the above-mentioned laser marking is performed on the near-infrared absorbing substrate 2, the (first) near-infrared absorbing layer 4, or on other substrates, layers, etc. to be laser marked, if any. In the operation of such laser marker device 39, a drive unit 42 which is a drive device equipped with a motor and the like controlled by a control unit 40 (a separate computer external to the laser marker device 39 can also function as the control unit 40) equipped with various control circuits and the like, such as a CPU or a built-in control circuit, drives the head of the laser light irradiation unit 43 toward the near-infrared absorbing substrate 2, the (first) near-infrared absorbing layer 4, and the like (moves (scans) the head) as already described, while the laser light irradiation unit 43 (in one example, a laser light irradiation device equipped with an Nd:YAG laser which is a device that generates laser light with a laser wavelength of 1064 nm, and equipped with various devices for irradiating the laser light to a target, such as a head) irradiates near-infrared laser light (which may be a near-infrared laser beam) from the head toward the near-infrared absorbing substrate 2, the (first) near-infrared absorbing layer 4, and the like. Incidentally, the memory unit 41, which is equipped with a storage device such as a semiconductor memory, a magnetic disk, etc., stores various data such as characters, images, etc. to be drawn by laser marking and that the control unit 40 appropriately reads and uses to control the operation of the laser marker device 39, and the laser marker device 39 draws the characters, images, etc. stored in the memory unit 41 on the near-infrared absorbing substrate 2, the (first) near-infrared absorbing layer 4, etc. There are many known laser marker devices, so they will not be described in further detail here.

[0086] (Example of near infrared absorbing ink) Below, experimental results of various laminates (offset prints) produced using a cesium tungsten oxide-containing ink and a lanthanum hexaboride-containing ink as near-infrared absorbing inks that can be used in the present invention will be described, while comparing them with experimental results of offset prints produced using an ytterbium oxide-containing ink as a comparative example.

[0087] Comparative Example 1 An ink containing 25% by weight of ytterbium oxide was prepared by mixing ytterbium oxide (III) 3N5 powder with an ink medium containing monomers, synthetic resins, and other non-infrared absorbing materials in a weight ratio of 25:75. Using the ink containing ytterbium oxide prepared in this way, printing was performed on a portion of a substrate of fine paper using an offset printing machine (offset printability tester IGT C1 (manufactured by IGT Testing Systems)). The obtained print was made into the laminate of Comparative Example 1, and photographed using an infrared visualization device VSC8000 (manufactured by Foster and Freeman) with a filter attached to the camera lens of the device that cuts light with wavelengths of 925 nm or less.

[0088] Example 1 Cesium tungsten oxideCs 0.33 A dispersion containing WO3 was mixed with the same ink medium as in Comparative Example 1, which contains monomers, synthetic resins, and other non-infrared absorbing materials, so that the weight ratio of cesium tungsten oxide to all other components was 2:98, to prepare an ink containing cesium tungsten oxide at a content of 2% by weight. Using the ink containing cesium tungsten oxide prepared in this manner, printing was performed on a portion of a substrate, which was a wood-free paper, using an offset printing machine (offset printability tester IGT C1 (manufactured by IGT Testing Systems)). The obtained print was used as the laminate of Example 1, and was photographed using an infrared visualization device VSC8000 (manufactured by Foster and Freeman) with a filter attached to the camera lens of the device that cuts light with wavelengths of 925 nm or less.

[0089] FIG. 54 shows infrared photographs of the ytterbium oxide-containing ink and the cesium tungsten oxide-containing ink prepared in Comparative Example 1 and Example 1 taken by the infrared camera, respectively, and infrared photographs of the printed matter offset-printed as described above using each ink taken by the infrared camera. From the photographs of each ink, it can be seen that both the ytterbium oxide-containing ink and the cesium tungsten oxide-containing ink exhibit near-infrared absorption, but the near-infrared absorption could not be visually confirmed in the printed matter offset-printed with the ytterbium oxide-containing ink. On the other hand, in the printed matter offset-printed with the cesium tungsten oxide-containing ink with a low content, the difference in brightness between the non-printed area and the printed area could be visually confirmed, and it was confirmed that the printed area has near-infrared absorption.

[0090] The results of the above experiments are summarized in the table below. [Table 1]

[0091] In the above table, the "film thickness" refers to the film thickness of the ytterbium oxide-containing ink layer or the cesium tungsten oxide-containing ink layer formed by offset printing, but these are not measured values, but are reference values ​​assuming a typical film thickness formed in offset printing. The film thickness formed in offset printing in each of the examples described below is also estimated to be about 1 μm to about 3 μm. In addition, experiments were performed under similar conditions such as printing density for all examples in this specification, and the film thickness is considered to be similar in theory. In addition, the "infrared absorptance" in Example 1 is a value obtained using the reflectance (the ratio of the intensity of reflected light when irradiated light is reflected on the surface of a printed material, which is the ratio of the intensity of reflected light from the target printed material surface to the intensity of reflected light from the base material surface (reference part) that serves as a reference) measured using a JASCO V-670 ultraviolet-visible-near infrared spectrophotometer (manufactured by JASCO Corporation) (absorbance (%) = 100 - reflectance (%)).

[0092] Next, cesium tungsten oxide (Cs 0.33 Offset printing was performed using a near-infrared absorbing ink with a WO3) content (content) of 2% by weight, and each of the resulting printed matter was laser-printed using a laser marker device, and the reflectance of electromagnetic waves in the visible light to near-infrared wavelength range was measured for the printed and unprinted parts. Note that, as in Example 1, "reflectance" in the following examples refers to the ratio of the intensity of reflected light when irradiated light is reflected on the surface of the printed matter, and is the ratio of the intensity of reflected light from the target printed matter surface to the intensity of reflected light from the reference substrate surface (reference part) (this is a value obtained by measurement using a JASCO V-670 ultraviolet-visible-near-infrared spectrophotometer (manufactured by JASCO Corporation)). The "reflectance" in the above-mentioned Example 1 and the following Examples 2 to 11 can be generally defined by the following formula. Reflectance (%) of the target part (target surface) = {(Intensity of reflected light from the target part (target surface)) / (Intensity of reflected light from the reference part (reference surface))} x 100

[0093] Example 2 Cesium tungsten oxideCs 0.33 A dispersion containing WO3 was mixed with monomers, synthetic resins, auxiliaries, etc. so that the weight ratio of cesium tungsten oxide to all other components was 2:98, to prepare an ink containing cesium tungsten oxide at a content of 2% by weight. The ink containing cesium tungsten oxide prepared in this manner was used to print on a substrate, a PC (polycarbonate) sheet, using an offset printing machine (offset printability tester IGT C1 (manufactured by IGT Testing Systems)). The resulting print was used as the laminate of Example 2, and the reflectance of visible light to near-infrared light at wavelengths of 400 nm to 2000 nm on the printed surface before laser printing was measured using a JASCO V-670 ultraviolet-visible-near-infrared spectrophotometer (manufactured by JASCO Corporation). In addition, as a laser marker device, The printed surface was laser-printed with a 1064 nm Nd:YAG laser beam using TIFF0007653057000002.tif977. The reflectance of the laser-printed area in the visible to near-infrared range of wavelengths from 400 nm to 2000 nm was measured using a JASCO V-670 ultraviolet-visible-near-infrared spectrophotometer (manufactured by JASCO Corporation).

[0094] Example 3 Cesium tungsten oxideCs 0.33 A dispersion containing WO3 was mixed with monomers, synthetic resins, auxiliaries, etc. so that the weight ratio of cesium tungsten oxide to all other components was 2:98, to prepare an ink containing cesium tungsten oxide at a content of 2% by weight. The ink containing cesium tungsten oxide prepared in this manner was used to print on a substrate PET-G (copolyester) sheet using an offset printing machine (offset printability tester IGT C1 (manufactured by IGT Testing Systems)). The resulting print was used as the laminate of Example 3, and the reflectance of visible light to near-infrared light at wavelengths of 400 nm to 2000 nm on the printed surface before laser printing was measured using a JASCO V-670 ultraviolet-visible-near-infrared spectrophotometer (manufactured by JASCO Corporation). In addition, as a laser marker device, The printed surface was laser-printed using a 1064 nm Nd:YAG laser and TIFF0007653057000003.tif977. The reflectance of the laser-printed area in the visible to near-infrared range of 400 nm to 2000 nm was measured using a JASCO V-670 ultraviolet-visible-near-infrared spectrophotometer (manufactured by JASCO Corporation).

[0095] Example 4 Cesium tungsten oxideCs 0.33A dispersion containing WO3 was mixed with monomers, synthetic resins, auxiliaries, etc. so that the weight ratio of cesium tungsten oxide to all other components was 2:98, to prepare an ink containing cesium tungsten oxide at a content of 2% by weight. The ink containing cesium tungsten oxide prepared in this manner was used to print on a substrate PVC (polyvinyl chloride) sheet using an offset printing machine (offset printability tester IGT C1 (manufactured by IGT Testing Systems)). The resulting print was used as the laminate of Example 4, and the reflectance of visible light to near-infrared light at wavelengths of 400 nm to 2000 nm on the printed surface before laser printing was measured using a JASCO V-670 ultraviolet-visible-near-infrared spectrophotometer (manufactured by JASCO Corporation). In addition, as a laser marker device, The printed surface was laser-printed using a 1064 nm Nd:YAG laser and TIFF0007653057000004.tif977. The reflectance of the laser-printed area in the visible to near-infrared range of wavelengths from 400 nm to 2000 nm was measured using a JASCO V-670 ultraviolet-visible-near-infrared spectrophotometer (manufactured by JASCO Corporation).

[0096] The results of measuring the reflectance in Examples 2 to 4 are shown in Figure 55. The results of measuring the reflectance in Example 2 are shown in Figure 56, the results of measuring the reflectance in Example 3 in Figure 57, and the results of measuring the reflectance in Example 4 in Figure 58, all extracted from the graph in Figure 55. In the graphs in Figures 55 to 58, the values ​​on the horizontal axis are the wavelength (nm) of the electromagnetic wave, and the values ​​on the vertical axis are the reflectance (%) of the electromagnetic wave of the wavelength indicated by the value on the horizontal axis on the printed surface or laser-printed portion.

[0097] As is clear from the graphs of Figures 55 to 58, it can be seen that the reflectance increases (absorbance decreases) in the near-infrared region by laser marking, regardless of which substrate is used. The amount of increase varies depending on the wavelength on the horizontal axis, but it can be seen that in the near-infrared region of 780 nm to 2000 nm, the reflectance increases by at least 5%, and generally 10% to 15%, or more, by laser marking. Also, as a general trend, the change in reflectance before and after laser marking in the visible light wavelength range is smaller than the change in reflectance before and after laser marking in the near-infrared region, so it is believed that laser marking can depict characters, images, etc. that are relatively difficult to see with the naked eye or with a general camera.

[0098] Next, the substrate sheet was coated with high-quality paper and was doped with different amounts of cesium tungsten oxide (Cs 0.33 Offset printing was performed using six types of near-infrared absorbing inks having different WO3 contents (contents), and the reflectance of the printed surface (near-infrared absorbing ink layer) of each of the produced prints to electromagnetic waves in the visible light to near-infrared wavelength range was measured. The definition of reflectance and the equipment used for measuring reflectance are the same as those in Examples 1 to 4 above.

[0099] (Examples 5 to 10) Cesium tungsten oxideCs 0.33 A dispersion containing WO3, monomers, synthetic resins, auxiliaries, etc. is mixed in a mixture in such a way that the weight ratio of cesium tungsten oxide to all other components is: (Example 5) 0.5:99.5 Example 6 1:99 (Example 7) 1.3:98.7 (Example 8) 2:98 (Example 9) 3:97 (Example 10) 6:94 By mixing the inks so that the content of cesium tungsten oxide was 0.5% by weight to 6% by weight, six kinds of inks were prepared. Each of the inks containing cesium tungsten oxide prepared in this manner was used to print on the above-mentioned wood-free paper sheet as the substrate by an offset printing machine (offset printability tester IGT C1 (manufactured by IGT Testing Systems)). The six kinds of prints obtained were used as the laminates of Examples 5 to 10, and the reflectance of visible light to near infrared light at wavelengths of 400 nm to 2000 nm was measured using a JASCO V-670 ultraviolet-visible-near infrared spectrophotometer (manufactured by JASCO Corporation).

[0100] The results of measuring the reflectance in the above Examples 5 to 10 are shown in FIG. 59. In the graph of FIG. 59, the value on the horizontal axis is the wavelength (nm) of the electromagnetic wave, and the value on the vertical axis is the reflectance (%) of the electromagnetic wave on the printed surface at the wavelength indicated by the value on the horizontal axis. It can be seen that, at least in the near-infrared wavelength range, the greater the content of cesium tungsten oxide, the lower the reflectance at the same wavelength. A similar tendency can be seen in the visible light wavelength range. That is, the higher the content of cesium tungsten oxide in the ink, the easier it is to recognize an image, etc., offset printed using the ink using the ink using a near-infrared camera, etc., but in this case, the visible light reflectance is also lower, so the possibility of it being visible to the naked eye or a general camera, etc. is also increased, and it is considered preferable to select an appropriate content of cesium tungsten oxide in terms of security.

[0101] Next, offset printing was performed on a PC (polycarbonate) substrate sheet using a near-infrared absorbing ink with a lanthanum hexaboride (LaB6) content (content) of 0.3% by weight, and the resulting printed matter was laser-printed using a laser marker device, and the reflectance of electromagnetic waves in the visible light to near-infrared wavelength range was measured in the printed and unprinted parts. In this example, the reflectance is also the ratio of the intensity of reflected light when irradiated light is reflected on the surface of the printed matter, and is the ratio of the intensity of reflected light from the target printed matter surface to the intensity of reflected light from the reference substrate surface (reference part) (a value obtained by measurement using a JASCO V-670 ultraviolet-visible-near-infrared spectrophotometer (manufactured by JASCO Corporation)).

[0102] Example 11 A dispersion liquid containing lanthanum hexaboride (LaB6) was mixed with monomers, synthetic resins, auxiliaries, etc. so that the weight ratio of lanthanum hexaboride to all other components was 0.3:99.7, to prepare an ink containing 0.3% by weight of lanthanum hexaboride. The ink containing lanthanum hexaboride prepared in this manner was used to print on a substrate, a PC (polycarbonate) sheet, using an offset printing machine (offset printability tester IGT C1 (manufactured by IGT Testing Systems)). The resulting printed matter was used as the laminate of Example 11, and the reflectance of visible light to near-infrared light at wavelengths of 400 nm to 2000 nm on the printed surface before laser printing was measured using a JASCO V-670 ultraviolet-visible-near-infrared spectrophotometer (manufactured by JASCO Corporation). In addition, as a laser marker device, The printed surface was laser-printed using a 1064 nm Nd:YAG laser beam using TIFF0007653057000005.tif977. The reflectance of the laser-printed area in the visible to near-infrared range of wavelengths from 400 nm to 2000 nm was measured using a JASCO V-670 ultraviolet-visible-near-infrared spectrophotometer (manufactured by JASCO Corporation).

[0103] The results of the reflectance measurements carried out in Example 11 above are shown in Figure 60. In the graph of Figure 60, the values ​​on the horizontal axis are the wavelengths (nm) of electromagnetic waves, and the values ​​on the vertical axis are the reflectance (%) of the printed surface or laser-printed portion of electromagnetic waves of the wavelengths indicated by the values ​​on the horizontal axis.

[0104] As is clear from the graph in Figure 60, it can be seen that laser marking increases reflectance (decreases absorbance) in the near-infrared region. The extent of the increase varies depending on the wavelength on the horizontal axis, but it can be seen that in the near-infrared region of 780nm to 1400nm, laser marking increases reflectance by roughly 5% to 14%. Also, as a general trend, the change in reflectance before and after laser marking in the visible light wavelength range is smaller than the change in reflectance before and after laser marking in the near-infrared region of about 800nm ​​to 1200nm, so it is believed that laser marking can depict characters, images, etc. that are relatively difficult to see with the naked eye or with a general camera.

[0105] (Example of use) In each of the above embodiments, specific examples of the medium and laminate of the present invention, and a system and method using the medium and laminate of the present invention for controlling the operation of a moving object have been described. However, the medium and laminate of the present invention are not limited to the specific examples described so far, and the medium and laminate of the present invention can be used for purposes other than the specific uses described. [Industrial Applicability]

[0106] The present invention can be used to autonomously move robots, vehicles, automated products, etc. indoors, for example, for automating indoor security, inspection, inventory, etc., but can be used for any purpose, including but not limited to this. [Explanation of symbols]

[0107] 1. Laminate or medium 2. Substrate layer or near infrared absorbing substrate 3. Area irradiated with laser light 4 (First) Near-infrared absorbing layer 5 Colored or fluorescent printed layer 6 Second near-infrared absorbing layer 7 First Near-Infrared Absorption Region 8. Second Near-Infrared Absorption Region 9 Near-infrared reflective layer 10. Abrasion-resistant hard coat layer 11 Adhesive layer 12 Release film 13~15 Wall 16 Ceiling A1~D1 Information display medium A2~D2 Information display medium 17 Mobile objects (vehicles) 18 Mobile body 19 Near-infrared camera (imaging section) 20~23 wheels 24 Distance sensor section 25 Motion control section 26 Power transmission mechanism, direction control mechanism, etc. 27 Communications Department 28 Power system (battery, power circuit, etc.) 29 Image Processing Section 30 Code information processing section 31 Control signal generator 32 Infrared camera lens 33 Infrared sensor unit (including cooler, etc.) 34 Memory (storage devices) 35 Processing circuit (A / D converter, etc.) 36 Communications Department 37 Cable (communication signal line) 38 Power system (battery, power circuit, etc.) 39 Laser marker device 40 Control section 41 Storage section 42 Drive (scanning) unit 43 Laser irradiation unit

Claims

1. An information display section at least partially containing a near-infrared absorbing material including cesium tungsten oxide or lanthanum hexaboride, and in which the near-infrared absorbing property of a target portion containing the near-infrared absorbing material is reduced at least in a predetermined wavelength range by applying laser light to the target portion. Equipped with The distribution of near-infrared absorptivity in the information display unit indicates instruction information for a moving object. Information display medium.

2. A substrate layer having near-infrared transmittance or reflectivity; a near-infrared absorbing layer including the near-infrared absorbing material including cesium tungsten oxide or lanthanum hexaboride; The information display medium according to claim 1 , wherein the near-infrared absorbing layer includes the information display portion.

3. 3. The information display medium according to claim 1, further comprising a printed layer containing a colored ink composition or a fluorescent ink composition, the printed layer and the information display portion at least partially overlapping each other.

4. The information display medium according to claim 3 , wherein the print layer displays an in-plane pattern similar to an in-plane pattern of a surface on which the information display medium is placed.

5. A base layer; a first near-infrared absorbing layer including the first near-infrared absorbing material, the first near-infrared absorbing material including cesium tungsten oxide or lanthanum hexaboride; a second near infrared absorbing layer comprising a second near infrared absorbing material different from cesium tungsten oxide and lanthanum hexaboride; The information display medium according to claim 1 , wherein the first near-infrared absorbing layer includes the information display portion.

6. A base layer; Near infrared absorbing layer The laminate is configured as a laminate comprising: The near infrared absorbing layer is a first area including a first near infrared absorbing material, the near infrared absorbing material including cesium tungsten oxide or lanthanum hexaboride; a second region including a second near infrared absorbing material different from cesium tungsten oxide and lanthanum hexaboride; The information display medium according to claim 1 , wherein the first area includes the information display portion.

7. 7. The information display medium according to claim 5, wherein the second near-infrared absorbing material includes at least one of antimony tin oxide, indium tin oxide, and copper pyrophosphate.

8. A base layer; a near infrared absorbing layer comprising the near infrared absorbing material comprising the cesium tungsten oxide or lanthanum hexaboride; a near-infrared reflective layer including a near-infrared reflective material; The information display medium according to claim 1 , wherein the near-infrared absorbing layer includes the information display portion.

9. The information display medium according to claim 8 , wherein the near-infrared reflective material includes at least one of titanium oxide, silicon oxide, and tin oxide.

10. An information display medium according to any one of claims 1 to 9; The moving body and A system comprising: a near-infrared imaging unit that images the information display portion of the information display medium; an operation control unit that controls an operation of the moving object using the instruction information acquired by imaging of the near-infrared imaging unit; A system comprising:

11. An information display section at least partially containing a near-infrared absorbing material including cesium tungsten oxide or lanthanum hexaboride, and in which the near-infrared absorbing property of a target portion containing the near-infrared absorbing material is reduced at least in a predetermined wavelength range by applying laser light to the target portion. and writing instruction information for a moving body onto the information display portion of an information display medium comprising: a laser beam projected onto the information display portion to change a distribution of near-infrared absorptivity within the information display portion.

12. The information display medium is A substrate layer having near-infrared transmittance or reflectivity; a near-infrared absorbing layer including the near-infrared absorbing material including cesium tungsten oxide or lanthanum hexaboride; and the near-infrared absorbing layer includes the information display portion.

13. 13. The information writing method according to claim 11, wherein the information display medium further comprises a printed layer containing a colored ink composition or a fluorescent ink composition, and the printed layer and the information display portion at least partially overlap each other.

14. The information writing method according to claim 13 , wherein the printing layer displays an in-plane pattern similar to an in-plane pattern of a surface on which the information display medium is placed.

15. The information display medium is A base layer; a first near-infrared absorbing layer including the first near-infrared absorbing material, the first near-infrared absorbing material including cesium tungsten oxide or lanthanum hexaboride; a second near infrared absorbing layer comprising a second near infrared absorbing material different from cesium tungsten oxide and lanthanum hexaboride; and the first near-infrared absorbing layer includes the information display portion.

16. The information display medium is A base layer; Near infrared absorbing layer The laminate is configured as a laminate comprising: The near infrared absorbing layer is a first area including a first near infrared absorbing material, the near infrared absorbing material including cesium tungsten oxide or lanthanum hexaboride; a second region including a second near infrared absorbing material different from cesium tungsten oxide and lanthanum hexaboride; 12. The method of claim 11, wherein the first area includes the information display portion.

17. 17. The information writing method according to claim 15, wherein the second near infrared absorbing material includes one or more of antimony tin oxide, indium tin oxide, and copper pyrophosphate.

18. The information display medium is A base layer; a near infrared absorbing layer comprising the near infrared absorbing material comprising the cesium tungsten oxide or lanthanum hexaboride; a near-infrared reflective layer including a near-infrared reflective material; and the near-infrared absorbing layer includes the information display portion.

19. 20. The information writing method according to claim 18, wherein the near-infrared reflective material includes at least one of titanium oxide, silicon oxide, and tin oxide.

20. A method for controlling the operation of a moving object including a near-infrared imaging unit and an operation control unit, The near-infrared imaging unit captures an image of the information display unit of the information display medium according to claim 1 ; the operation control unit controls an operation of the moving object using the instruction information acquired by imaging by the near-infrared imaging unit; The method includes:

Images