JP7056060B2 - Manufacturing method of laser marking recording medium - Google Patents

Description

INDUSTRIAL APPLICABILITY According to the present invention, with respect to a laser marking recording medium to which anti-counterfeiting treatment has been applied and a method for manufacturing the same, it is possible to easily visually recognize that the recorded laser marking recording has been tampered with, and the anti-counterfeiting tampering function can be provided. The present invention relates to an enhanced laser marking recording medium and a method for manufacturing the same.

Conventionally, it is called laser engraving or laser marking that prints characters and symbols by irradiating a sheet or card whose main component is resin with laser light in the visible light region, infrared light region, or ultraviolet light region. Technology is known. In the present specification, they are collectively referred to as laser marking.

Laser marking is a technique for preventing counterfeiting, tampering, and alteration. It penetrates the surface of the base material, irradiates the inside with laser light, and absorbs the laser light with an additive that absorbs the laser light added to the base material. It is a technique for forming individual image information such as characters, symbols, and portraits inside the base material by causing the base material to develop or discolor, carbonize the inside of the base material, or remove the concealing layer. This is mainly applied to plastic base materials such as polycarbonate and PET, and has been widely used in recent years for security media such as driver's licenses, ID cards, and passports containing ID information that identifies and authenticates individuals.

However, in recent years, incidents using unauthorized ID cards and passports and damage caused by accidents have become problems, and new technologies for preventing forgery and falsification of such security media are required. For example, in Patent Document 1, a laser beam irradiation color-developing layer is provided on the card core inside the card laminate, and printing is performed on the inside of the card without damaging the card surface, thereby preventing tampering from the card surface. Technology has been proposed.

However, in recent years, falsification methods using laser light have become widely known. For example, it is possible to forge by cutting the base material from the surface and physically destroying the image. Furthermore, as illustrated in FIG. 9, an additional laser beam is applied to the facial photograph 102 to show hair, whiskers, etc. It is possible to add and falsify the additional record 104 of, and to falsify ("3" to "8") and add (add "FG") 103 to the characters 101, so forgery prevention. It is said that the effect is not sufficient.

Japanese Patent No. 4391286

The present invention has been made to solve the above-mentioned problems of forgery and falsification in the prior art, and the subject thereof is a laser marking recording medium, which is a laser beam for forgery and falsification. Provided is a recording medium capable of deterring forgery and falsification by making it possible to clarify that the addition or rewriting of the record has been performed by clearly visually recognizing the addition or rewriting by the laser, and the manufacturing method thereof. There is something in it.

In order to solve the above problems, the invention according to claim 1 of the present invention is
At least, it is a recording medium in which an internal color-developing layer that develops color by irradiation with laser light and a surface material that transmits laser light are sequentially laminated on a core base material that does not transmit laser light.
The laser marking recording medium is characterized in that an external color-developing layer that develops a color different from that of the internal color-developing layer or develops cloudiness by irradiation with a laser beam is further laminated on the surface material.

Further, the invention according to claim 2 is
The laser marking recording medium according to claim 1, wherein the cloudiness developed in the external color layer by irradiation with laser light is formed by foaming.

Further, the invention according to claim 3 is
The laser marking recording medium according to claim 1 or 2, wherein an optical device layer in which an optical device composed of a hologram, a diffraction grating, or both is formed is laminated on the external color-developing layer. Is.

Further, the invention according to claim 4 is
The first step of sequentially laminating an internal color-developing layer that develops color by irradiation with laser light and a surface material that transmits laser light on a core base material that does not transmit laser light.
A second step of irradiating a laser beam from the surface material to develop a color of the internally developed layer according to predetermined recorded information, and recording the predetermined recorded information on the internally developed layer.
A third step of further laminating an external color-developing layer that develops a color different from that of the internal color-developing layer or white turbidity by irradiation with a laser beam on the surface material.
It is a method of manufacturing a laser marking recording medium characterized by having at least.

Further, the invention according to claim 5 is
The laser marking record according to claim 4, wherein the third step is a step of thermally transferring the external color-developing layer from a thermal transfer film in which at least the external color-developing layer is laminated on a heat-resistant base film. It is a method of manufacturing a medium.

The invention according to claim 6 is the invention.
The method for manufacturing a laser marking recording medium according to claim 4, wherein the third step is a step of laminating the external color layer by an inkjet method.

Further, the invention according to claim 7 is
The fourth aspect of the present invention comprises the fourth step of laminating an optical device layer in which an optical device composed of a hologram, a diffraction grating, or both thereof is formed on the external color-developing layer, following the third step. 6. The method for manufacturing a laser marking recording medium according to any one of 6.

Further, the invention according to claim 8 is
The laser marking recording according to claim 7, wherein the fourth step is a step of thermally transferring the optical device layer from a thermal transfer film in which at least the optical device layer is laminated on a heat-resistant base film. It is a method of manufacturing a medium.

Further, the invention according to claim 9 is
The third step is to obtain the surface material from a thermal transfer film in which an optical device layer in which an optical device composed of at least a hologram or a diffraction grating or an optical device composed of at least a hologram or a diffraction grating is formed on a heat-resistant base film and the external color-developing layer are sequentially laminated. The method for manufacturing a laser marking recording medium according to claim 5, wherein the step is a step of simultaneously performing thermal transfer so that the side becomes the external color-developing layer.

According to the first aspect of the present invention, the internal color layer is irradiated with laser light through a surface material that transmits laser light, and characters, images, symbols and other predetermined information (hereinafter, together recorded information) are subjected to laser marking. () Is mainly recorded in black or dark gray on a laser marking recording medium (hereinafter, may be simply referred to as a recording medium), and the surface material is further irradiated with laser light to have a color different from that of the internal color layer. By using a recording medium having a structure in which external color-developing layers having the property of developing color or cloudiness are laminated, achromatic colors such as black and dark gray recorded on the internal color-developing layer can be recorded due to forgery or falsification of the recording medium. When laser light is additionally irradiated to falsify, add, or correct information, the external color layer develops a color different from that of the internal color layer, such as red and blue, or becomes cloudy. As a result, it becomes possible to easily see that the additional irradiation of the laser beam has been performed for addition or alteration, and a recording medium that can easily visually indicate that the forgery or alteration has been performed can be obtained.

Further, according to the second aspect of the present invention, since the white turbidity developed in the extrinsic color layer is formed by foaming, not only the color but also the portion of the extrinsic color layer swells and the properties change, for example, the base color. It is possible to obtain a recording medium in which it is possible to more easily see that the additional irradiation of the laser beam has been performed even if the recording medium is provided with a complicated print pattern on the surface.

Further, according to the invention of claim 3, the external color layer is scraped off by further laminating an optical device layer on which an optical device composed of a hologram, a diffraction grating, or both is formed on the external color layer. Depending on the method, even when trying to conceal the forgery or tampering by preventing the external color layer that develops chromatic colors from developing when additional irradiation of laser light is performed, for example, it is further laminated on the upper layer. Since the optical device layer is scraped off at the same time, it can be easily visually recognized that the scraped optical device layer is scraped off, so that it is possible to provide a recording medium in which it is difficult to conceal forgery or alteration.

Further, according to the invention of claim 4, the internally colored layer laminated on the core base material that does not transmit the laser light is irradiated with the laser light from the surface material side that transmits the laser light, and the recorded information is achromatic such as black. After recording with coloring, each information recorded in the internal coloring layer is falsified by laminating an external coloring layer that expresses a color different from the internal coloring layer, for example, achromatic color, on the surface material by irradiation with laser light. When additional irradiation of laser light is applied to add information or add information, a recording medium that can easily see that the external color development layer located above the color has been added and tampered with has been added or tampered with is a normal laminating process. A manufacturing method that can be manufactured without requiring a special process can be obtained.

Further, according to the invention of claim 5, since the external color-developing layer formed on the heat-resistant base film can be formed by heat transfer by a known means such as a thermal head or a heat roller, external color development having a uniform film thickness can be achieved. The layer can be easily formed by a dry process that does not require a drying step or the like.

Further, according to the invention of claim 6, by forming the external color layer by an inkjet method that can be realized by a relatively small device, the external color layer can be provided in a pattern, and a plurality of inkjet nozzles are used. This makes it possible to use a plurality of inks that develop different colors, and it is possible to provide the external color layer in a wider variety of ways.

Further, according to the invention of claim 7, the attempt to forge or falsify is concealed by preventing the external color layer from developing color when the additional irradiation of the laser beam is performed by a method such as scraping off the external color layer. Even if it is intended, a recording medium that is difficult to conceal forgery or falsification because it can be easily visually recognized that it has been scraped can be easily manufactured by a known laminating process.

Further, according to the invention of claim 8, since the optical device layer formed on the heat-resistant base film can be formed by thermal transfer by a known means such as a thermal head or a heat roller, the optical device having a uniform film thickness can be formed. The layer can be easily formed by a dry process that does not require a drying step or the like.

Further, according to the invention of claim 9, since the optical device layer and the external color-developing layer formed on the heat-resistant base film can be formed by heat transfer at the same time by a known means such as a thermal head or a heat roller, they are uniform. The optical device layer and the external color development layer having a thickness can be easily formed in one step by a dry process that does not require a drying step or the like.

It is explanatory drawing of the structure of 1st Embodiment of the laser marking recording medium of this invention, and the aspect of recording of recording information. It is explanatory drawing of the aspect when the addition or falsification was performed in the 1st Embodiment of the laser marking recording medium of this invention. It is explanatory drawing of another aspect when addition or falsification was performed in 1st Embodiment of the laser marking recording medium of this invention. It is explanatory drawing of the structure of the 2nd Embodiment of the laser marking recording medium of this invention. It is explanatory drawing of the aspect when the addition or falsification was performed in the 2nd Embodiment of the laser marking recording medium of this invention. It is explanatory drawing of the aspect when the tampering which scraped off the external color-developing layer was performed in the 2nd Embodiment of the laser marking recording medium of this invention. It is explanatory drawing of the structure of the 3rd Embodiment of the laser marking recording medium of this invention, and the mode of recording the recording information. It is explanatory drawing of the mode when addition or falsification was performed with the recording medium of another structure of 1st Embodiment of the laser marking recording medium of this invention. It is explanatory drawing of the conventional laser marking recording medium and the state of falsifying the recording medium.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The present invention is not construed as being limited to the following embodiments. Further, in the following, the same numbers and symbols may be added to equivalent items and the description may be omitted.

FIG. 1 is an explanatory diagram of a configuration of a first embodiment of the laser marking recording medium of the present invention and an aspect of recording information. As shown in FIG. 1A, the recording medium 10 has an internal color-developing layer 2 that mainly develops an achromatic color such as black or gray on both sides of the core base material 1 by irradiation with laser light, and a laser on the surface side thereof. A surface material 3 made of a resin that transmits light is laminated, and as shown in FIG. 1B, a laser beam 30 is irradiated from the surface material 3 side to a predetermined color-developing layer 2. Recorded information 21 such as characters, symbols, and images is formed. Needless to say, the internal color-developing layer 2 and the surface material 3 may be provided on only one side surface.

Subsequently, as shown in FIG. 1 (c), an external color layer 4 that develops a color different from that of the internal color layer 2 by irradiation with a laser beam, for example, a chromatic red color, is placed on the heat-resistant base film 6. The thermal transfer ribbon 50 formed so as to be thermally transferable is laminated on the surface material 3 side, and the external color layer 4 is thermally transferred by a known heat source (not shown) such as a thermal head or a heat roller to laminate as shown in FIG. 1 (d). It is configured. In addition to the illustrations, the recording medium 10 and the thermal transfer ribbon 50 may be appropriately provided with an adhesive layer, a peeling layer, a printing layer, or the like, if necessary.

FIG. 2 shows an embodiment in which the recording medium 10 configured as described above is later irradiated with a laser beam to illegally falsify or add to the recording. Since the core base material 1 does not transmit the laser light, the laser light 40 for falsifying or adding the recording is irradiated from the external color development layer 4 side, but before the laser light 40 reaches the internal color development layer 2. Since it passes through the external color-developing layer 4, the external color-developing layer 4 is formed with a color-developing portion 41 that absorbs the laser beam 40 and develops a red color.

FIG. 2B is a plan view of this from the surface material 3 side, and while the regular recording information 21 recorded on the internal color layer 2 is recorded in black, black gray, etc., it is recorded later. The part where the laser beam was irradiated to falsify or add to the characters and the characters were falsified (from "3" to "8") or added ("FG"), and the hair and beard were added, is the part of the external color layer 4. The color-developing portion 41 becomes a mode in which the red color can be seen, and it is possible to easily visually recognize that an illegal additional recording has been performed.

FIG. 8 is an example in which the external color-developing layer 4 is formed into a layer that foams and becomes cloudy when irradiated with laser light 40 for falsification or additional writing. When the laser beam 40 is irradiated from the surface material 3 side of the recording medium 13, gas bubbles are generated in the external color-developing layer 4 due to the heat, and the bubbles are trapped in the external color-developing layer 4 and foam and become cloudy. It is an embodiment of forming a ridge 43 which is a formed portion. When the external color layer 4 has such an aspect, it is easy to see because the gas bubbles are enclosed in a cloudy state and the appearance changes, and in particular, the base is colored or a printing layer or the like is provided. In such cases, the contrast becomes higher and it becomes easier to see.

FIG. 3 shows another aspect when an attempt is made to tamper with or add to the recorded information by irradiating the laser light, and the laser light 40 for adding or tampering is made more powerful and outside. The laser marking record 22 is added to the internal color development layer 2 by passing through the color development layer 4 and further reaching the internal color development layer 2. In such a case, it is assumed that laser marking recording can be performed on the internal color layer 2, but at the same time, the powerful laser light 40 acts more strongly on the external color layer 4 to cover the external color layer 4 over a wider range. Will be colored.

FIG. 3B is a plan view of this from the surface material 3 side, and the laser marking recording 22 is performed on the internal color layer 2 at the portion irradiated with the laser beam 40 for addition or falsification. Since the external color-developing layer 4 develops a color different from that of the internal color-developing layer 2, for example, red over a wider area, the red color-developing portion 42 overlaps the laser marking record 22 and further borders the laser marking record 22. It can also be easily visually recognized that the laser beam 40 was formed and irradiated with the laser beam 40 for addition or falsification.

FIG. 4 is an explanatory diagram of a configuration of a second embodiment of the laser marking recording medium of the present invention. First, the recording medium 11 has an embodiment in which the internal color-developing layer 2 and the surface material 3 are laminated on both sides of the core base material 1 in the same manner as that shown in FIG. 1, and is the same as described here in FIG. Is irradiated with laser light from the surface material 3 side, and recording information 21 such as predetermined characters, symbols, and images is formed in black on the internal color-developing layer 2.

Subsequently, a heat transfer ribbon 51 in which the optical device layer 5 and the external color development layer 4 are sequentially formed on the heat-resistant base film 6 so as to be heat transferable is laminated on the surface material 3 side, and a known heat source such as a thermal head or a heat roller ( The optical device layer 5 and the external color development layer 4 are thermally transferred by (not shown) to form a laminated structure as shown in the lower view of FIG.

FIG. 5 shows an embodiment in which the recording medium 11 configured as described above is later irradiated with a laser beam to illegally falsify or add to the recording. Since the core base material 1 does not transmit the laser light, when the laser light 40 is irradiated from the external color layer 4 side to falsify or add to the recording, the external color layer 4 is before the laser light 40 reaches the internal color layer 2. As in the first embodiment, the external color-developing layer 4 absorbs the laser beam 40 to form a color-developing portion 41 having a color different from that of the internal color-developing layer 2, for example, red. ..

Therefore, while the regular recording information 21 recorded in the internal color layer 2 is recorded in black, black gray, etc., the portion irradiated with the laser beam for falsification or addition later is colored externally. It can be seen that the red color can be seen as the color-developing portion 41 of the layer 4, and it can be easily seen that the illegal additional recording was performed as in the first embodiment. When the laser light for falsifying or adding a record is made stronger so that the laser marking record is formed on the internally developed color layer 2, it can be easily visually recognized as in the first embodiment.

Further, when the recording medium 11 of the present embodiment is irradiated with laser light for falsification or falsification later, the external color layer 4 develops color so that the falsification or falsification is not visually recognized. Therefore, as shown in FIG. 6, it can be assumed that after the external color layer 4 itself is scraped off, an attempt is made to record an illegal additional record 22 on the internal color layer 2.

In that case, as shown in FIG. 6, when the external color-developing layer 4 is scraped off, the optical device layer 5 on the upper layer is also scraped off at the same time, so that an optical pattern formed by a hologram or a diffraction grating formed on the optical device layer is formed. By making it invisible, it is easy to visually recognize that unauthorized scraping has been performed, and a recording medium with higher security can be obtained.

FIG. 7 is a cross-sectional view of a third embodiment of the laser marking recording medium of the present invention. Here, only the core base material 1, the internal color-developing layer 2, and the surface material 3 are shown. In the recording medium 12 of the present embodiment, the internally developed color layer 2 is composed of two layers, a black layer 25 and a concealing layer 26. In order to record characters, images, etc. on the internal color layer 2, the concealing layer is as shown in FIG. 7 (b) by irradiating a laser beam from the surface material 3 side in the same manner as in each of the above-described embodiments. Since 26 is engraved (engraved) due to condensation caused by the heat energy of the laser beam 30, the black recording unit 27 is expressed by exposing the underlying black layer 25. Is.

Although the external color development layer and the optical device layer are omitted, they can be formed by laminating in the same manner as in the first or second embodiment. Therefore, when the laser beam is irradiated for falsification or addition of the record, it can be easily visually recognized as in the first and second embodiments.

In each of the above-described embodiments, the case where the recorded image is provided on one side with respect to the core base material has been described, but it is also possible to provide the internal color development layer, the external color development layer, and the optical device layer on both sides. Therefore, it goes without saying that the same effect can be obtained even when the image is recorded on both sides.

Hereinafter, the configuration of the laser marking recording medium of the present invention will be described in more detail.

<Recording medium>
The laser marking recording medium of the present invention can be composed of a plurality of sheet base materials including a core base material 1 and an internal color-developing layer 2 that mainly develops black or dark gray when irradiated with a laser beam.

(Sheet base material)
The sheet base material such as the core base material 1, the internally colored layer 2, and the surface material 3 may be made of paper, but it is preferable to use a sheet base material containing resin as a main component, assuming that it has a card shape.
Examples thereof include polycarbonate (PC), plant-derived polycarbonate (bio-PC), polyethylene terephthalate (PET), amorphous polyethylene terephthalate (PETG), polyvinyl chloride (PVC), ABS resin and the like. The film thickness of the sheet base material is preferably in the range of 10 to 500 μm.

(Internal color layer)
The internal color-developing layer 2 that develops an achromatic color by irradiation with a laser beam is preferably one that can develop or change color to an achromatic color such as black or dark gray by irradiation with a laser beam, but is not limited thereto. As such, for example, a resin in which an additive having absorption in the wavelength range of the laser light to be used is added to each of the resins exemplified in the previous section can be used. As an additive (laser light absorber) that absorbs laser light in the wavelength range, a material that can absorb laser light and convert it into heat energy can be used. By using a material that can absorb laser light and convert it into heat energy, it is possible to develop a black color by carbonizing the resin around the laser light absorber.

Materials that can absorb laser light and convert it into heat energy include, for example, dyes and silicon-containing inorganic compounds, silicon-containing dyes, radiation-absorbing substances such as metal silicates, inorganic fillers such as hydrated alumina, and phosphates. Pigments containing, non-white titanium acid metal salts, black organic dyes, non-black inorganic lead compounds, graphite, carbon black, graphite, metal hydroxides and / and those containing metal hydrous compounds and colorants. Be done. These materials can be appropriately selected depending on the wavelength range of the laser to be used and the compatibility with the resin, and the addition amount can be appropriately set in consideration of the influence on the energy absorption efficiency and the physical properties of the sheet base material of the internal color development layer. ..

As shown in the third embodiment, when the black layer is composed of two layers, a black layer and a concealing layer, for example, the black layer is heated by absorbing the laser light exemplified above into various resins exemplified above. Among the materials that can be converted into energy, it is formed by containing a material that exhibits black color such as carbon black and graphite, and the concealing layer is laminated with an ink in which white pigments such as titanium oxide, calcium carbonate, and zinc oxide are dispersed in a known binder resin. It can be formed by painting.

Laser light includes solid-state lasers such as ruby laser, titanium sapphire laser, YAG laser (Nd: YAG laser is infrared), carbon dioxide gas laser (infrared), helium neon laser (red), and argon ion laser (mainly blue). Or green), gas lasers such as excima lasers (mainly ultraviolet), semiconductor lasers, and the like. Above all, it is preferable to use a laser in the infrared region. The output of the laser beam can be appropriately set according to the purpose.

(External color layer)
As the external color-developing layer 4, a layer in which the irradiated portion (and its vicinity) develops a color different from that of the internal color-developing layer by irradiating the sheet base material with laser light can be used. As a different color, it is preferable to use a chromatic color because it is highly distinguishable from the color of the internal color-developing layer. It is obtained by containing (manufactured by Dainichiseika Kogyo), etc., and colors such as red, blue, and yellow can be obtained. It should be noted that the reason why the irradiated portion is colored by irradiating the laser beam is that the crystal structure of the metal ion of the pigment contained in the external color-developing layer is changed by the energy of the laser beam and the chemical change occurs, and the color is developed or. It is known that this is due to discoloration.

Furthermore, as materials that absorb laser light and develop color, lead carbonate, lead sulfate, lead stearate, lead white, silver acetate, cobalt oxalate, cobalt carbonate, yellow iron oxide, basic bismuth acetate, bismuth oxide, bismuth hydroxide , Nickel acetyl acetate, nickel lactate, copper citrate, bismuth such as copper carbonate, nickel, copper, lead, manganese, chromium, antimony, iron, cobalt, tin, etc. It may be appropriately selected from known compounds. Leuco dyes can also be used. In selecting the material and the amount to be added thereof, it may be appropriately selected and set in consideration of the wavelength range of the laser light to be used, compatibility with the resin, and the like.

In addition, the color development of the external color development layer is to make it easy to visually recognize that the laser light has been additionally irradiated. Or, it may be in a mode in which the appearance property changes. For example, when the base of the recording medium is colored or a pattern is printed, it may be better to make it cloudy or foam.

(Optical device layer)
The optical device layer 5 is formed by thinly laminating a transparent to translucent inorganic substance vapor deposition layer having a high refractive index on a layer in which a pattern of an optical device such as a hologram or a diffraction grating is embossed on a transparent resin, and further providing a protective resin layer. It is a thing. As the material of the resin layer to be embossed and the protective resin layer, a thermoplastic resin, a thermosetting resin, an ultraviolet ray, an electron beam curable resin, or the like can be used. Examples of the thermoplastic resin include acrylate resin, polyurethane, and acrylic polyol resin, but any resin can be used as long as it can be used in consideration of compatibility with other layers.

Further, the inorganic substance vapor deposition layer is preferably transparent or light-colored transparent, and TiO2, SiO, ZnS or the like may be used. The thickness of the inorganic substance vapor deposition layer is preferably 100 Å to 1000 Å. In addition to the above-mentioned layers, an adhesive layer, a peeling layer, and the like may be appropriately provided as needed.

<Thermal transfer ribbon>
The base film 6 of the heat transfer ribbons 50 and 51 is not particularly limited as long as it has appropriate heat resistance and strength, but for example, polyethylene terephthalate, polyethylene naphthalate, biaxially stretched polypropylene, cellophane, polycarbonate, polyimide, polyethylene. , Polyvinyl chloride, polystyrene, unsaturated polyester, synthetic resin film such as polymethylmethacrylate, and papers such as condenser paper and paraffin paper can be exemplified alone or in combination. Of these, polyethylene terephthalate film is preferable in consideration of physical characteristics, processability, cost, and the like. Further, those having a thickness in the range of 2 μm or more and 100 μm or less can be preferably used.

1 ... Core base material 2 ... Internal color development layer 3 ... Surface material 4 ... External color development layer 5 ... Optical device layer 6 ... Base film 10, 11, 12, 13 ... Recording medium 21 ... Recording information 22 ... Additional or falsified laser marking recording 30 ... Laser light 40 ... Laser light for adding or falsifying 41, 42 ... External color layer Color-developing part 43 ... Ridge (foamed and cloudy part)
50, 51 ... Thermal transfer ribbon

Claims (6)

The first step of sequentially laminating an internal color-developing layer that develops color by irradiation with laser light and a surface material that transmits laser light on a core base material that does not transmit laser light.
A second step of irradiating a laser beam from the surface material to develop a color of the internally developed layer according to predetermined recorded information, and recording the predetermined recorded information on the internally developed layer.
A third step of further laminating an external color-developing layer that develops a color different from that of the internal color-developing layer or white turbidity by irradiation with a laser beam on the surface material.
A method for producing a laser marking recording medium, which comprises at least. The laser marking recording according to claim 1 , wherein the third step is a step of thermally transferring the external color-developing layer from a thermal transfer film in which at least the external color-developing layer is laminated on a heat-resistant base film. Method of manufacturing the medium. The method for manufacturing a laser marking recording medium according to claim 1 , wherein the third step is a step of laminating the external color-developing layer by an inkjet method. The first aspect of the present invention comprises the fourth step of laminating an optical device layer in which an optical device composed of a hologram, a diffraction grating, or both thereof is formed on the external color-developing layer, following the third step. 3. The method for manufacturing a laser marking recording medium according to any one of 3. The laser marking recording according to claim 4 , wherein the fourth step is a step of thermally transferring the optical device layer from a thermal transfer film in which at least the optical device layer is laminated on a heat-resistant base film. Method of manufacturing the medium. The third step is to obtain the surface material from a thermal transfer film in which an optical device layer in which an optical device composed of at least a hologram or a diffraction grating or an optical device composed of at least a hologram or a diffraction grating is formed on a heat-resistant base film and the external color-developing layer are sequentially laminated. The method for manufacturing a laser marking recording medium according to claim 2 , wherein the step is a step of simultaneously performing thermal transfer so that the side becomes the external color-developing layer.

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