JP2017052261A - Laser recording device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser recording device that records an image by scanning a laser beam, the recorder being simplified in device structure while maintaining and improving the quality of a recorded image.SOLUTION: The laser recording device records by emitting a laser beam LB to a recording medium 10 comprising a plurality of thermal recording layers that respectively include thermal materials of different color-development temperatures and that are layered from the surface side to which a laser beam LB is emitted so that the threshold temperatures of the thermal materials included via an intermediate layer for heat insulation and heat transfer are increased. The control part of the laser recording device records on a thermal recording layer on which recording is to be carried out by emitting a laser beam LB, such that when recording is carried out on the thermal recording layers of higher threshold temperatures, the power density of the laser beam LB is set relatively higher, and when recording on thermal recording layers of lower threshold temperatures, a practically longer time is set.SELECTED DRAWING: Figure 5

Description

  Embodiments described herein relate generally to a laser recording apparatus.

  In the conventional laser recording method, when laser recording is directly performed on a recording medium, only monochromatic recording using a change in color due to carbonization of the recording medium or reaction of the color former at the recording position (laser irradiation position) can be performed.

  Also, it is in the form of a film such as a transfer film or a laminate film, or a plastic object provided with such a film, and a laser light condensing position is controlled on such a plastic object to record a multicolor image. A method to do this has also been proposed.

Japanese Patent No. 4091423 JP 2005-138558 A Japanese Patent No. 3509246 JP 2008-179131 A JP 2010-131878 A JP 2004-25739 A

  However, in the prior art, since it was necessary to have a plurality of laser light source devices having different wavelengths and a plurality of ultraviolet light irradiation devices for stopping color development, it was difficult to reduce the device cost and downsize the device. It was. In addition, when the laser condensing position is changed in accordance with the color developing layer, the quality of the recorded image may be easily deteriorated due to variations in the recording medium, distortion, unevenness, optical system, color developing layer thickness, and the like. .

  The present invention has been made in view of the above, and in a laser recording apparatus that performs image recording by scanning a laser beam, a laser capable of simplifying the apparatus configuration while maintaining and improving the quality of a recorded image It is to provide a recording apparatus.

The laser recording apparatus of the embodiment includes heat-sensitive materials having different color development threshold temperatures, and laser light is emitted so that the threshold temperature of the heat-sensitive material included through an intermediate layer that performs heat insulation and heat transfer is increased. The laser recording apparatus performs recording by irradiating the recording medium with a plurality of thermosensitive recording layers laminated from the irradiated surface side with the laser beam.
Then, the control unit of the laser recording apparatus increases the power density of the laser light relatively as the recording time of the thermal recording layer having a higher threshold temperature, and effectively increases the irradiation time as the recording time of the thermal recording layer having a lower threshold temperature. As described above, recording is performed on the heat-sensitive recording layer to be recorded by irradiation with laser light.

FIG. 1 is an explanatory diagram of a schematic configuration of a recording medium used in the embodiment. FIG. 2 is an explanatory diagram of the coloring principle in the monochromatic color development of the embodiment. FIG. 3 is an explanatory diagram of an example of laser irradiation conditions. FIG. 4 is a schematic configuration block diagram of the laser recording apparatus according to the embodiment. FIG. 5 is an image diagram of laser irradiation as seen from a cross section perpendicular to the stacking direction of each layer of the recording medium. FIG. 6 is an image diagram of irradiation of the laser beam LB viewed from the incident direction of the laser beam LB. FIG. 7 is a diagram illustrating the correspondence between the laser irradiation image and the laser beam LB irradiation image viewed from the incident direction of the laser beam LB, as viewed from a cross section perpendicular to the stacking direction of each layer of the recording medium. . FIG. 8 is an explanatory diagram of a correspondence relationship between an image diagram of laser irradiation viewed from a cross section perpendicular to the stacking direction of each layer of the recording medium and an image of laser beam LB irradiation viewed from the incident direction of the laser beam LB. . FIG. 9 is an explanatory diagram of the numbering of the pixels constituting the image corresponding to the input image data. FIG. 10 is a process flowchart for shortening the total recording time in laser recording. FIG. 11 is an explanatory diagram for determining the sub-recording area in the second modification. FIG. 12 is a detailed process flowchart of a calculation process of a plurality of areas that can be recorded with the period Ttem in the second modification. FIG. 13 is an explanatory diagram of the effect of the second modification. FIG. 14 is a detailed process flowchart of a calculation process of a plurality of areas that can be recorded in the cycle Ttem in the third modification. FIG. 15 is an explanatory diagram for determining the sub recording area in the third modification. FIG. 16 is an explanatory diagram of the effect of the fourth modification. FIG. 17 is an explanatory diagram of a fifth modification. FIG. 18 is an explanatory diagram of the coloring principle in the multi-color coloring according to the fourth embodiment. FIG. 19 is an explanatory diagram of an energy-time relationship in which each coloring layer in the fourth embodiment exceeds a threshold temperature for coloring. FIG. 20 is an explanatory diagram of an example of laser irradiation conditions. FIG. 21 is an explanatory diagram of a specific configuration example of the recording medium. FIG. 22 is an explanatory diagram of a coloring method using a plurality of colors mixed in the first aspect. FIG. 23 is an explanatory diagram of a single color development method. FIG. 24 is an operation flowchart of the first aspect of the fourth embodiment. FIG. 25 is a flowchart of the conversion process into CMYRBK data. FIG. 26 is an operation flowchart of a modification of the first mode of the fourth embodiment. FIG. 27 is an operation flowchart of the second mode of the fourth embodiment. FIG. 28 is a flowchart of conversion processing into CMYRBK data. FIG. 29 is an explanatory diagram of a schematic configuration of a recording medium used in the fifth embodiment. FIG. 30 is an explanatory diagram of recording control according to the sixth embodiment. FIG. 31 is an operation flowchart of the sixth embodiment. FIG. 32 is a flowchart of the conversion process into CMYRGBK data. FIG. 33 is an operation flowchart of the first aspect of the fourth embodiment. FIG. 34 is an operation flowchart of the second aspect of the sixth embodiment. FIG. 35 is a flowchart of the conversion process into CMYRGBK data.

Hereinafter, embodiments will be described in detail with reference to the drawings.
[1] First Embodiment First, the principle of the first embodiment will be described.
In the laser recording method of the first embodiment, the heat generated on at least the protective layer 18 by laser irradiation is conducted to each layer and the temperature of each layer changes, depending on how the heat is applied by the laser, that is, the laser irradiation conditions. In this recording method, each layer is selectively colored by control.

FIG. 1 is an explanatory diagram of a schematic configuration of a recording medium used in the embodiment.
As shown in FIG. 1, the recording medium 10 includes a low-temperature coloring layer 13, a first spacer layer 14, an intermediate-temperature coloring layer 15, a second spacer layer 16, a high-temperature coloring layer 17 and a protective layer 18 on a substrate 12. They are stacked in order. Here, the low-temperature coloring layer 13, the medium-temperature coloring layer 15, and the high-temperature coloring layer 17 constitute a heat-sensitive recording layer (low-temperature heat-sensitive recording layer, medium-temperature heat-sensitive recording layer, and high-temperature heat-sensitive recording layer) on which image recording is performed. The layer 14 and the second spacer layer 16 constitute an intermediate layer that performs heat insulation and heat transfer.

In the above configuration, the substrate 12 holds the low temperature coloring layer 13, the first spacer layer 14, the intermediate temperature coloring layer 15, the second spacer layer 16, the high temperature coloring layer 17 and the protective layer 18.
The low temperature coloring layer 13 is a layer containing a temperature indicating material as a heat sensitive material that develops color when its temperature is equal to or higher than the first threshold temperature Tl.

The first spacer layer 14 is a layer that provides a thermal barrier when the low temperature coloring layer 13 is not colored, and suppresses heat transfer from the medium temperature coloring layer 15 side to the low temperature coloring layer 13.
The intermediate temperature coloring layer 15 is a layer including a temperature indicating material as a heat sensitive material that develops a color when the temperature is equal to or higher than the second threshold temperature Tm (> Tl).

The second spacer layer 16 is a layer that provides a thermal barrier when the medium temperature coloring layer 15 is not colored, and suppresses heat transfer from the high temperature coloring layer 17 side to the medium temperature coloring layer 15.
The high-temperature coloring layer 17 is a layer including a temperature indicating material as a heat-sensitive material that develops a color when the temperature becomes equal to or higher than a third threshold temperature Th (> Tm).

  The protective layer 18 is a layer for protecting the low temperature coloring layer 13, the first spacer layer 14, the intermediate temperature coloring layer 15, the second spacer layer 16, and the high temperature coloring layer 17.

FIG. 2 is an explanatory diagram of the coloring principle in the monochromatic color development of the embodiment.
FIG. 2A is a diagram for explaining the principle when the low-temperature coloring layer 13 is individually colored.
FIG. 2B is a diagram for explaining the principle when the intermediate temperature coloring layer 15 is individually colored.
FIG. 2C is a diagram for explaining the principle when the high-temperature coloring layer 17 is individually colored.

When only the low temperature coloring layer 13 is colored, heat needs to be transmitted from the laser irradiation position to the low temperature coloring layer 13, but at the same time, the temperature of the intermediate temperature coloring layer 15 does not exceed the second threshold temperature Tm, and Recording is performed under laser irradiation conditions in which the temperature of the high-temperature coloring layer 17 does not exceed the third threshold temperature Th.
As a result, as shown in FIG. 2A, color is developed in the color development region 21 of the low-temperature color development layer 13.

When only the intermediate temperature coloring layer 15 is colored, it is necessary to transmit heat from the laser irradiation position to the intermediate temperature coloring layer 15, but at the same time, the temperature of the high temperature coloring layer 17 does not exceed the third threshold temperature Th. In addition, heat transfer is suppressed by the spacer layer 14, and recording is performed under laser irradiation conditions in which the temperature of the low temperature coloring layer 13 does not exceed the first threshold temperature Tl.
As a result, as shown in FIG. 2B, color is developed in the color development region 22 of the intermediate temperature color development layer 15.

Further, when only the high temperature coloring layer 17 is colored, heat needs to be transferred from the laser irradiation position to the high temperature coloring layer 17, but at the same time, the heat transfer is suppressed by the spacer layer 16 and the spacer layer 14, Recording is performed under laser irradiation conditions in which the temperature of the intermediate temperature coloring layer 15 does not exceed the second threshold temperature Tm and the temperature of the low temperature coloring layer 13 does not exceed the first threshold temperature Tl.
As a result, as shown in FIG. 2C, color is developed in the color development region 23 of the high-temperature color development layer 17.

FIG. 3 is an explanatory diagram of an example of laser irradiation conditions.
As shown in FIG. 3, the power density and recording time of the laser beam for coloring each of the low temperature coloring layer 13, the medium temperature coloring layer 15 and the high temperature coloring layer 17 are set as power densities PD1, PDm and PDh, respectively. When the times are th, tm, and tl,
PDl <PDm <PDh and th <tm <tl
Set to satisfy the conditions.

In other words, for power density:
PDl + α1 = PDm + α2 = PDh (α1>α2> 0)
And In this case, the values of α1 and α2 are appropriately set in advance according to the materials constituting the low temperature coloring layer 13, the medium temperature coloring layer 15, and the high temperature coloring layer 17.

Also, regarding the recording time,
th + β1 = tm + β2 = tl (β1>β2> 0)
And In this case, the values of β1 and β2 are appropriately set in advance according to the materials constituting the low temperature coloring layer 13, the medium temperature coloring layer 15, and the high temperature coloring layer 17.

That is, in order to selectively develop the low temperature coloring layer 13, the power density PDl is relatively smallest and the recording time tl is relatively largest.
By irradiating the laser beam under such conditions, the temperature of the intermediate temperature coloring layer 15 does not exceed the second threshold temperature Tm at the stage where heat is transmitted to the high temperature coloring layer 17 and the intermediate temperature coloring layer 15, and the high temperature coloring layer. The temperature of the low-temperature coloring layer 13 can exceed the first threshold temperature Tl while the temperature of 17 does not exceed the third threshold temperature Th.

  Further, in order to selectively color the high temperature coloring layer 17, the power density PDh is relatively largest and the recording time th is relatively shortest. By irradiating the laser beam under such conditions, at the stage where heat is transmitted to the intermediate temperature coloring layer 15 and the low temperature coloring layer 13, the temperature of the intermediate temperature coloring layer 15 and the threshold temperature of the low temperature coloring layer 13 are not exceeded. Only the color developing layer 17 can exceed the threshold temperature.

  In order to selectively color only the intermediate temperature coloring layer 15, the power density PDm and the recording time tm are set to relatively intermediate values as described above.

  By irradiating the laser under such conditions, the medium temperature coloring is performed without exceeding the threshold temperature of the high temperature coloring layer 17 and the threshold temperature of the low temperature coloring layer 13 at the stage where heat is transmitted to the high temperature coloring layer 17 and the low temperature coloring layer 13. Only the layer 15 can exceed the threshold temperature.

  As described above, since each layer corresponding to the three primary colors can be selectively developed, full-color recording combining the three primary colors becomes possible. Further, according to the method of the present embodiment, since the three primary colors can be recorded in the stacking direction of each layer of the recording medium, the three primary colors are relatively low compared to the case where they are separately arranged along a two-dimensional plane. Images that look good even at resolution can be provided.

A more detailed embodiment will now be described.
FIG. 4 is a schematic configuration block diagram of the laser recording apparatus according to the embodiment.
The laser recording apparatus 100 effectively emits a laser beam LB for recording to the recording medium 10 placed on the recording stage 101, and a laser beam LB emitted from the laser head unit 102. A driving unit 103 for driving the recording stage 101 for scanning, and a control unit 104 configured as a microcomputer for controlling the laser head unit 102 and the driving unit 103 based on recording image data input from the outside; It is equipped with.

  In the above configuration, the laser head unit 102 includes the spot control unit 102A as an optical system that controls the focal position of the laser beam LB and the spot diameter of the laser beam LB under the control of the control unit 104.

  In addition, the control unit 104 controls the power density, irradiation time, focal position, spot diameter, and the like of the laser light LB emitted from the laser head unit 102 based on a control program stored in advance.

  First, with respect to the recording medium 10 in which three coloring layers corresponding to any one of the three primary colors, each having different threshold temperatures Tl, Tm, and Th, are changed for each color to be developed. Then, a method for selectively developing the three primary colors by controlling the recording time of each color will be described.

  In the first embodiment, the scanning speed of the laser beam LB is controlled as a parameter for controlling the recording time. That is, the recording time is controlled to be relatively long by relatively slowing the scanning speed of the laser beam LB.

FIG. 5 is an image diagram of laser irradiation as seen from a cross section perpendicular to the stacking direction of each layer of the recording medium.
FIG. 6 is an image diagram of the irradiation of the laser beam LB viewed from the incident direction of the laser beam LB.
In FIG. 6, the position of the spot SPT of the laser beam LB per unit time is schematically shown.

FIGS. 5A and 6A show the power density and scanning speed of the laser beam LB when the low temperature coloring layer 13 is selectively colored, and when only the low temperature coloring layer 13 is colored. For example, the laser is scanned at a power density PD1 = 0.01 to 15.0 [W / cm ² ] and a scanning speed V1 = 1.0 to 90 [mm / s].

Here, when the power density PDl <0.01 [W / cm ² ], the temperature rises to the first threshold temperature Tl that is the threshold temperature of the low-temperature coloring layer 13. This is because if the power density PD1> 15.0 [W / cm ² ], the temperature rises too much and the medium temperature coloring layer 15 and the high temperature coloring layer 17 may develop colors simultaneously. .

  Further, if the scanning speed V1 <1.0 [mm / s], the energy applied to the same portion is too large, so that the temperature rises too much and the medium temperature coloring layer 15 and the high temperature coloring layer 17 may be colored simultaneously. This is because if the scanning speed V1> 90 [mm / s], the temperature may not rise to the threshold temperature (first threshold temperature Tl) of the low-temperature coloring layer 13.

5B and 6B show the laser power density and scanning speed when the intermediate temperature coloring layer 15 is selectively colored, and when only the intermediate temperature coloring layer 15 is colored. For example, the laser is scanned at a power density PDm = 1.0 to 100.0 [W / cm ² ] and at a scanning speed V2 = 10 to 500 [mm / s].

Here, the power density PDm is in the above range when the power density PDm <1.0 [W / cm ² ], the temperature rises to the second threshold temperature Tm that is the threshold temperature of the intermediate temperature coloring layer 15. If the power density PDm> 100.0 [W / cm ² ], the temperature rises too much and the high temperature coloring layer 17 may develop color, and the temperature transmitted to the low temperature coloring layer 13 This is because there is a possibility that the color may be developed exceeding the threshold temperature (first threshold temperature Tl).

  If the scanning speed V2 <10 [mm / s], too much energy is applied to the same location, so that the temperature rises too much and the high temperature coloring layer 17 may be colored, and the low temperature coloring layer 13 There is also a possibility that the color transmitted to the color temperature exceeds the threshold temperature (first threshold temperature Tl), and when the scanning speed V2> 500 [mm / s], the second threshold temperature of the intermediate temperature coloring layer 15 is reached. This is because the temperature may not rise to the threshold temperature Tm.

5C and 6C show the scanning speed and power density of the laser beam LB when the high temperature coloring layer 17 is selectively colored, and when only the high temperature coloring layer 17 is colored. For example, the laser is scanned at a power density PDh = 150 to 1000 [W / cm ² ] and a scanning speed V3 = 750 to 6000 [mm / s].

Here, if the power density PDh is in the above range, if the power density PDh <150 [W / cm ² ], the temperature may not rise to the threshold temperature of the high-temperature coloring layer 17, and the power density PDh If it is> 1000 [W / cm ² ], the temperature rises so much that the protective layer 18 on the surface layer may be thermally destroyed, and the heat generated in the surface layer is too high. This is because, when transmitted to the color forming layer 15 and the low temperature color forming layer 13, the temperature of these layers may exceed the threshold temperature (the first threshold temperature Tl or the second threshold temperature Tm) and the color may be developed simultaneously.

  In addition, when the scanning speed V3 <750 [mm / s], the energy applied to the same portion is too large, so that the temperature rises too much and the protective layer 18 on the surface layer may be thermally destroyed. When the heat generated in the surface layer is too large, the temperature of these layers exceeds the threshold temperature (the first threshold temperature Tl or the second threshold temperature Tm) when transmitted to the medium temperature coloring layer 15 or the low temperature coloring layer 13. This is because there is a possibility that the color is developed at the same time, and if the scanning speed V3> 6000 [mm / s], the temperature may not rise to the third threshold temperature Th that is the threshold temperature of the high-temperature coloring layer 17.

  The power density and the scanning speed depend greatly on the absorption rate when the energy of the laser beam is absorbed by the surface layer. In the above example, the protective layer is a surface layer made of a material having an absorption rate of about 1% to 50%. It is an example used for.

In the above configuration, it is desirable to use the following materials for the recording medium.
For example, as the base material 12, polyester resin, polyethylene terephthalate (PET), glycol-modified polyester (PET-G), polypropylene (PP), polycarbonate (PC), polyvinyl chloride (PVC), styrene butadiene copolymer (SBR), poly A resin that can be processed into a film shape or a plate shape such as an acrylic resin, a polyurethane resin, or a polystyrene resin is used.

  Further, as a filler for the resin used for the recording medium, it is possible to use a resin such as silica, titanium oxide, calcium carbonate, alumina, etc., in which whiteness, surface smoothness, heat insulation, etc. are added to a base material.

  The above-mentioned resins and fillers are examples, and other materials can be used as long as processability and functionality are satisfied.

  The low-temperature coloring layer 13, the medium-temperature coloring layer 15, and the high-temperature coloring layer 17 are colored in three primary colors when a certain threshold temperature is exceeded using a highly transparent resin such as polyvinyl alcohol, polyvinyl acetate, or polyacryl as a binder. A leuco dye, a leuco dye or other temperature indicating material is used as a coloring material.

  Examples of leuco dyes, leuco dyes as color materials, and other temperature indicating materials include 3,3-bis (1-n-butyl-2-methyl-indol-3-yl) phthalide, 7- (1-butyl-2- Methyl-1H-indol-3-yl) -7- (4-diethylamino-2-methyl-phenyl) -7H-furo [3,4-b] pyridin-5-one, 1- (2,4-dichloro- Phenylcarbamoyl) -3,3-dimethyl-2-oxo-1-phenoxy-butyl- (4-diethylamino-phenyl) -carbamic acid isobutyl ester, 3,3-bis (p-dimethylaminophenyl) phthalide, 3,3 -Bis (p-dimethylaminophenyl) -6-dimethylaminophthalide (also known as crystal violet lactone = CVL), 3,3-bis (p-dimethylaminopheny ) -6-aminophthalide, 3,3-bis (p-dimethylaminophenyl) -6-nitrophthalide, 3,3-bis3-dimethylamino-7-methylfluorane, 3-diethylamino-7-chlorofluorane, 3 -Diethylamino-6-chloro-7-methylfluorane, 3-diethylamino-7-anilinofluorane, 3-diethylamino-6-methyl-7-anilinofluorane, 2- (2-fluorophenylamino) -6 -Diethylaminofluorane, 2- (2-fluorophenylamino) -6-di-n-butylaminofluorane, 3-piperidino-6-methyl-7-anilinofluorane, 3- (N-ethyl-p- Toluidino) -7- (N-methylanilino) fluorane, 3- (N-ethyl-p-toluidino) -6-methyl-7-anilinov Oran, 3-N-ethyl-N-isoamylamino-6-methyl-7-anilinofluorane, 3-N-methyl-N-cyclohexylamino-6-methyl-7-anilinofluorane, 3-N, Coloring dyes such as N-diethylamino-7-o-chloroanilinofluorane, rhodamine B-lactam, 3-methylspirodinaphthopyran, 3-ethylspirodinaphthopyran, 3-benzylspironaphthopyran can be mentioned. is there.

  Further, as the developer, any acidic substance used as an electron acceptor in the heat-sensitive recording material can be used, for example, an inorganic substance such as activated clay, acidic clay, inorganic acid, aromatic carboxylic acid, its anhydride or Examples thereof include organic developers such as metal salts, organic sulfonic acids, other organic acids, and phenolic compounds. Of these, phenolic compounds are preferred.

  More specific examples of the developer include bis-3-allyl-4-hydroxyphenylsulfone, polyhydroxystyrene, zinc salt of 3,5-di-t-butylsalicylic acid, and 3-octyl-5-methylsalicylic acid. Zinc salt, phenol, 4-phenylphenol, 4-hydroxyacetophenone, 2,2'-dihydroxydiphenyl, 2,2'-methylenebis (4-chlorophenol), 2,2'-methylenebis (4-methyl-6-t -Butylphenol), 4,4'-isopropylidenediphenol (also known as bisphenol A), 4,4'-isopropylidenebis (2-chlorophenol), 4,4'-isopropylidenebis (2-methylphenol), 4 , 4'-ethylenebis (2-methylphenol), 4,4'-thiobis (6-t-butyl-3- Tilphenol), 1,1-bis (4-hydroxyphenyl) -cyclohexane, 2,2'-bis (4-hydroxyphenyl) -n-heptane, 4,4'-cyclohexylidenebis (2-isopropylphenol) And phenolic compounds such as 4,4′-sulfonyldiphenol, salts of the phenolic compounds, salicylic acid anilide, novolac-type phenolic resin, benzyl p-hydroxybenzoate, and the like.

  The spacer layers 14 and 16 provided between the color-developing layers may be made of polypropylene (PP), polyvinyl alcohol (PVA), styrene butadiene copolymer (SBR), polystyrene, polyacryl, or the like.

On the other hand, the laser to be used is preferably a red to infrared laser having a strong thermal action, and the wavelength band is preferably 800 to 15000 nm. In particular, a YAG laser, a YVO ₄ laser, a CO ₂ laser, a semiconductor laser or the like used for thermal processing is preferable.

  The reason why the wavelength band of the laser beam LB is set to 800 to 15000 nm is that when the wavelength band of the laser beam LB is less than 800 nm, a special layer that absorbs light and converts it into heat in order to obtain a heat amount for color development is a surface layer. This is because it is necessary to use another color forming agent that generates color by light energy instead of heat.

  In addition, when the wavelength band of the laser beam LB exceeds 15000 nm, the beam waist at the focal point is not sufficiently reduced when the laser beam is collected by a lens or the like, and the size of a recordable pixel cannot be reduced. This is because it becomes difficult to record a high-resolution image.

  As described above, according to the first embodiment, since the recording time of each color can be controlled by changing the laser scanning speed for each color to be developed, the three primary colors can be selectively developed. The apparatus configuration can be simplified while maintaining and improving the quality of the recorded image.

[2] Second Embodiment In the first embodiment, the method for selectively developing the three primary colors by controlling the recording time of each color by changing the laser scanning speed for each color to be developed has been described. In the second embodiment, instead of changing the laser scanning speed, the laser scanning speed is made constant and the recording time is controlled by the number of scans.

  FIG. 7 is a diagram illustrating the correspondence between the laser irradiation image and the laser beam LB irradiation image viewed from the incident direction of the laser beam LB, as viewed from a cross section perpendicular to the stacking direction of each layer of the recording medium. .

  In the second embodiment, in order to control the recording time for selectively developing the three primary colors, the scanning speed of the laser beam LB is set to a constant value of, for example, 10 to 6000 [mm / s], and irradiation is repeated. The recording time is controlled by the number of times (number of scans).

FIG. 7A shows the power density and the number of scans when the low-temperature coloring layer 13 is selectively colored. When the low-temperature coloring layer 13 is colored, for example, 0.01 to 15.0 [W / Cm ² ], the same location is repeatedly scanned 3 to 50 times.
In FIG. 7, in order to facilitate understanding of the difference in the number of scans, the position of the laser spot SPT (laser irradiation position) when viewed from the laser incident direction is shifted up and down. The laser is irradiated repeatedly over the position.

Here, when the power density PDl is set to the above range, if the power density PDl <0.01 [W / cm ² ], the temperature rises to the threshold temperature (first threshold temperature Tl) of the low-temperature coloring layer 13. This is because if the power density PD1> 15.0 [W / cm ² ], the temperature rises too much and the medium temperature coloring layer 15 and the high temperature coloring layer 17 may develop colors simultaneously. .

  Also, the reason why the number of scans CT1 corresponding to the low temperature coloring layer 13 is in the above range is that when the number of scannings CT1 <3 [times], the temperature rises to the threshold temperature of the low temperature coloring layer 13 (first threshold temperature Tl). If the number of scans CT1> 50 [times], the energy applied to the same part is too large, and the temperature rises too much, so that the medium temperature coloring layer 15 and the high temperature coloring layer 17 may develop colors simultaneously. Because there is.

FIG. 7B shows the power density and the number of scans of the laser beam LB when the intermediate temperature coloring layer 15 is selectively colored. When only the intermediate temperature coloring layer 15 is colored, for example, 1. The same part is repeatedly scanned 1 to 30 times at a power density of 0 to 100.0 [W / cm ² ].

Here, when the power density PDm is set to the above range, if the power density PDm <1.0 [W / cm ² ], the temperature rises to the threshold temperature (second threshold temperature Tm) of the intermediate temperature coloring layer 15. If the power density PDm> 100.0 [W / cm ² ], the temperature rises too much and the high temperature coloring layer 17 may develop color, and the temperature transmitted to the low temperature coloring layer 13 This is because there is a possibility that the color will be developed beyond the threshold.

  The scanning number CT2 corresponding to the intermediate temperature coloring layer 15 is within the above range when the number of scanning times CT2 <1 [times], the temperature rises to the threshold temperature of the intermediate temperature coloring layer 15 (second threshold temperature Tm). This is because if the number of scans CT2> 30 [times], the energy applied to the same location is too large, so that the temperature rises too much and the high temperature coloring layer 17 may be colored, and the low temperature coloring layer. This is because the temperature transmitted to 13 may also exceed the threshold temperature (first threshold temperature Tl) to cause color development.

FIG. 7C shows the laser power density and the number of scans when the high temperature coloring layer 17 is selectively colored. When only the high temperature coloring layer 17 is colored, for example, 150 to 1000 [ The same spot is repeatedly scanned 1 to 10 times at a power density of [W / cm ² ].

Here, if the power density PDh is in the above range, if the power density PDh <150 [W / cm ² ], the temperature may not rise to the threshold temperature of the high-temperature coloring layer 17, and the power density PDh If it is> 1000 [W / cm ² ], the temperature rises too much, and the protective layer 18 on the surface layer may be thermally destroyed, and the heat generated on the surface layer is too large, resulting in low temperature color development. This is because when the temperature is transmitted to the layer 13 or the intermediate temperature coloring layer 15, the temperature of these layers exceeds the threshold temperature (the first threshold temperature Tl or the second threshold temperature Tm), and there is a possibility that the color is developed simultaneously.

Also, the reason why the number of scans CT3 corresponding to the high temperature coloring layer 17 is in the above range is that when the number of scannings CT3 <1 [times], the temperature rises to the threshold temperature of the high temperature coloring layer 17 (third threshold temperature Th). This is because if the number of scans CT3> 10 [times], the energy applied to the same location is too large, so that the temperature rises too much and the protective layer 18 on the surface layer may be thermally destroyed. At the same time, since the heat generated in the surface layer is too large, the temperature of these layers exceeds the threshold temperature (second threshold temperature Tm or first threshold temperature Tl) when transmitted to the medium temperature coloring layer 15 or the low temperature coloring layer 13. This is because there is a possibility of color development at the same time.
Other configurations and operations are the same as those in the first embodiment.

  As described above, according to the second embodiment, the recording time of each color can be controlled by changing the number of times of laser scanning for each color to be developed, so that the three primary colors can be selectively developed. The apparatus configuration can be simplified while maintaining and improving the quality of the recorded image.

[3] Third Embodiment In the first embodiment, the method for selectively developing the three primary colors by controlling the recording time of each color by changing the laser scanning speed for each color to be developed is described. In the third embodiment, instead of changing the laser scanning speed, the laser scanning speed is made constant, and the recording time is controlled by the waiting time (scan standby time) at the time of scanning.

  FIG. 8 is an explanatory diagram of a correspondence relationship between an image diagram of laser irradiation viewed from a cross section perpendicular to the stacking direction of each layer of the recording medium and an image of laser beam LB irradiation viewed from the incident direction of the laser beam LB. .

As shown in FIG. 8, in the third embodiment, in order to selectively develop the three primary colors, for example, the power density is set to a constant value of 1 to 20000 [W / cm ² ] and the scanning speed is set to 10 to 6000 [ mm / s], the number of scans is set to a constant value of 1 to 50, and control is performed with a waiting time (scan standby time) from the nth scan to the n + 1th scan when the laser scan is repeated. It is carried out.

  FIG. 8A schematically shows the power density, the scanning speed, and the number of scans when the low temperature coloring layer 13 is selectively colored. When the low temperature coloring layer 13 is colored, for example, the waiting time WT1 is set to 100 to 100,000 [μs], and the same location is repeatedly scanned at the above power density, scanning speed, and number of scans.

  Here, the reason why the waiting time WT1 is in the above range is that if the waiting time WT1 <100 [μs], the temperature rises too much and the medium temperature coloring layer 15 and the high temperature coloring layer 17 may develop colors simultaneously. If the waiting time WT1> 100000 [μs], the temperature of the low temperature coloring layer 13 may not rise to the threshold temperature.

  FIG. 8B schematically shows the power density, the scanning speed, and the number of scans of the laser beam LB when the intermediate temperature coloring layer 15 is selectively colored. When only the intermediate temperature coloring layer 15 is colored. For example, the waiting time WT2 is set to 10 to 10000 [μs], and the same portion is repeatedly scanned at the power density, the scanning speed, and the number of scans.

  Here, the reason why the waiting time WT2 is set in the above range is that if the waiting time WT1 <10 [μs], the temperature rises too much and the high temperature coloring layer 17 may be colored, and the low temperature coloring layer 17 This is because the temperature transmitted to 13 may also exceed the threshold and color may develop, and if the waiting time WT2> 10000 [μs], the temperature of the intermediate temperature coloring layer 15 may not rise to the threshold temperature.

  FIG. 8C schematically shows the laser power density, the scanning speed, and the number of scans when the high temperature coloring layer 17 is selectively colored. When only the intermediate temperature coloring layer 15 is colored, For example, the waiting time WT3 is set to 0.1 to 5000 [μs], and the same portion is repeatedly scanned at the power density, the scanning speed, and the number of scans.

Here, the reason for setting the waiting time WT3 in the above range is that if the waiting time WT1 <0.1 [μs], the temperature rises too much and the protective layer 18 on the surface layer may be thermally destroyed. In addition, since the heat that can be generated on the surface layer is too large, the temperature of these layers may exceed the threshold temperature when the heat is transmitted to the intermediate temperature coloring layer 15 or the low temperature coloring layer 13, and the coloring may occur at the same time. This is because if WT3> 5000 [μs], the temperature of the high-temperature coloring layer 17 may not rise to the threshold temperature.
Other configurations and operations are the same as those in the first embodiment.

  As described above, according to the third embodiment, the recording time of each color is controlled by changing the waiting time during irradiation with the laser beam LB for each color to be developed, and the three primary colors are selectively developed. Therefore, the apparatus configuration can be simplified while maintaining and improving the quality of the recorded image.

[4] Modified Example of First to Third Embodiments [4.1] First Modified Example In each of the above embodiments, the scanning speed of the laser beam LB, the number of scans of the laser beam LB (the number of small companies) or Although the waiting time is controlled individually, it may be configured to be controlled in combination.

[4.2] Second Modification In the above description, an image recording is performed for each recording dot. However, in the second modification, a plurality of recording dots (pixels) are arranged within a certain recording time. This is a modification of the case where the total recording time until the end of the image recording process on the recording medium 10 is shortened by adopting the recording structure.

  That is, in the second modification, the heat applied on the surface is applied to the lower layer (high temperature color layer 17 → intermediate temperature color layer 15 → low temperature) using a time lag from the irradiation of the laser beam LB to the heat transfer to each color layer. The total recording time is shortened by simultaneously recording other recording dots (pixels) while being transmitted to the coloring layer 13).

In the second modification, the laser beam LB is radiated to the same portion once or a plurality of times and at a constant cycle in order to stably raise the temperature to the color development threshold value in each recording dot.
By the way, since there are irradiation conditions of the laser beam LB suitable for developing each color, when the laser beam LB is irradiated a plurality of times, there is an optimum period in the second and subsequent irradiations.

Therefore, in the second modification, the recording area corresponding to the desired recording image is divided into a plurality of sub-recording areas that can be recorded at an optimum cycle in the second and subsequent irradiations, and the recording of each sub-recording area is finished. After that, the process proceeds to recording in the next sub-recording area, and by combining these records, a desired image is finally obtained.
In the following description, as irradiation conditions for selectively coloring a certain color developing layer (in this embodiment, the low temperature coloring layer 13, the medium temperature coloring layer 15 and the high temperature coloring layer 17),
・ Laser scanning speed at recording pixels: Vtem
-Laser scanning speed at non-recording pixels: Ve
・ Pitch in the sub-scanning direction: d
-Time period when repeatedly irradiating the same spot to a certain pixel: Ttem
And

Also, information such as pixels of the recorded image is designated as follows.
・ Width in the scanning direction of the recorded image (width in the scanning direction of the recording area): w
Width of the recorded image in the sub-scanning (height) direction (width of the recording area in the sub-scanning direction): H
・ Width of one side of one pixel: R
-Number of pixels in the scanning direction of the recorded image: w / R
-Number of pixels in the sub-scanning direction of the recorded image: H / R
· N pixels of the recording pixel data: _{I n}
-Position data of the nth pixel: P _n
Recording time in the unit recording area when recording up to the nth pixel: t _n
-Area number that can be recorded with T: X
_-Position of the end pixel of area X: P _fX
-Position of start pixel of area X: P _sX
-Distance from P _sX to P _n : D _n

FIG. 9 is an explanatory diagram of the numbering of the pixels constituting the image corresponding to the input image data.
Among the above information, the “n-th pixel” refers to a pixel at the upper left corner of a desired image (a rectangular image as a whole: corresponding to a recording area) as shown in FIG. As the pixel, it is numbered with the second pixel and the third pixel toward the right. Next to the right end (for example, the α pixel in the first column), the pixel at the left end one step down (the first pixel in the second column) Pixel: The pixel number when counted as (α + 1 pixel).

In the second modification, the low temperature coloring layer 13 is colored cyan (C), the medium temperature coloring layer 15 is magenta (M), and the high temperature coloring layer 17 is yellow (Y).
In this case, c, m, and y are used as subscripts to distinguish between the color development of the low temperature color development layer 13, the color development of the medium temperature color development layer 15, and the color development of the high temperature color development layer 17. When there is no subscript, it is not limited to any coloring layer, but generalized.

FIG. 10 is a process flowchart for shortening the total recording time in laser recording.
FIG. 11 is an explanatory diagram for determining the sub-recording area in the second modification.
First, when the recording image data is input (step S1), the control unit 104 converts the recording image data into CMY data (step S2).

  That is, when the recording image data 50 shown in FIG. 11A is input, the control unit 104, as shown in FIGS. 11B to 11D, cyan (C) data, magenta (M). Data and yellow (Y) data. In FIG. 11, four images (C, M, Y, K character images) of cyan single color, magenta single color, yellow single color, and black (= C + M + Y) correspond to the recorded image data for easy understanding. It is assumed that it is included in the image.

Next, the control unit 104 acquires CMY image data I and pixel position data P based on the converted cyan data, magenta data, and yellow data (step S3).
Subsequently, the control unit 104 sets a variable tem = 1 for specifying the recording cycle T (step S4).

Then, the control unit 104 records a plurality of areas (start points Ps1 to PsX and end points Pf1 to PfX of the plurality of sub-recording areas) that can be recorded with the period Ttem at the laser scanning speed Vtem at the recording pixel when the pixels are recorded. Further, calculation (calculation) is performed based on the laser scanning speed Ve at the non-recording pixel where the pixel is not recorded (step S5).
In the case of FIG. 11E, that is, for cyan data, the first sub-recording area (corresponding to the position of the pixel 61) is based on the laser scanning speed Vtem in the recording pixel 51 and the laser scanning speed Ve in the non-recording pixel 52. The start point Ps1 and the end point Pf1 range corresponding to the position of the pixel 62) and the second sub-recording area (the start point Ps2 corresponding to the position of the pixel 63 and the range of the end point Pf2 corresponding to the position of the pixel 64). Is calculated (calculated).

  In the case of FIG. 11F, that is, for magenta data, the first sub-recording area (corresponding to the position of the pixel 65) is based on the laser scanning speed Vtem in the recording pixel and the laser scanning speed Ve in the non-recording pixel. Start point Ps1 and end point Pf1 range corresponding to the position of the pixel 66) and second sub-recording area (start point Ps2 corresponding to the position of the pixel 67 and range of end point Pf2 corresponding to the position of the pixel 68) Is calculated (calculated).

  In the case of FIG. 11G, that is, for yellow data, there is only one sub-recording area based on the laser scanning speed Vtem at the recording pixel and the laser scanning speed Ve at the non-recording pixel. An area (a range of the start point Ps1 corresponding to the position of the pixel 69 and the end point Pf1 corresponding to the position of the pixel 70) is calculated (calculated).

Here, the calculation process (step S5) of a plurality of areas that can be recorded in the cycle Ttem will be described in detail.
FIG. 12 is a detailed process flowchart of a calculation process of a plurality of areas that can be recorded with the period Ttem in the second modification.

  In the second modified example, another pixel recording is advanced during the time using the time that the heat applied to the surface of the recording medium 10 by the irradiation of the laser beam LB is transmitted to the coloring layer in order to develop a certain coloring layer. Pixels that can be recorded during the optimum irradiation repetition period for color development are set as one sub-recording area.

First, the control unit 104 determines whether or not the previously set cycle t _n−1 is smaller than the cycle Ttem (step S411).

If it is determined in step S411 that the cycle tn _-1 is equal to or greater than the cycle Ttem (false) (step S411; No), the n-1st pixel is determined as one sub-recording area, and the nth pixel _{Is set as} the start point P _{sX + 1} of the next sub-recording area, and further, X _n = X + 1 in order to proceed to the next area with t _n = 0 (step S423), and the process proceeds to step S420.

If it is determined in step S411 that the previously set cycle t _n-1 is smaller (true) than the cycle Ttem (step S411; Yes), the control unit 104 sets (n-1) in the horizontal direction of the recorded image. And quotient A (integer part) + B (decimal part) (step S412).

Subsequently, the control unit 104 determines whether or not B = 0 (step S413).
If it is determined in step S413 that B = 0 (true) (step S413; Yes), the control unit 104 moves to a free-running movement from the rightmost pixel to the leftmost pixel one step lower in the cycle tn _−1. The necessary time is added, and the time necessary for idle running to move from the (n-1) th pixel to the start point _PsX of the area X is subtracted (step S414), and the process _proceeds to step S416.

If B ≠ 0 (false) in the determination in step S413 (step S413; No), the control unit 104 moves from the n−1th pixel to the start point _PsX of the area X from the cycle t _n−1. The time required for idle running is subtracted (step S415).
Next, the control unit 104 determines whether or not the pixel In is a recording pixel (step S416).

If it is determined in step S416 that the pixel In is a recording pixel (true) (step S416; Yes), the control unit 104 scans one pixel at the period tn and at the period tn−1 at the recording scanning speed. The time (R / Vtem) and the time required for idle running from the nth pixel to the start point _PsX are added and substituted (step S417), and the process _proceeds to step S419.

If it is determined in step S416 that the pixel In is not a recording pixel but a non-recording pixel (false) (step S416; No), the control unit 104 sets one pixel in the period tn and one period in the period tn-1. A value obtained by adding the idle running time (R / Ve) and the idle running time (D _n / Ve) required to move from the nth pixel to the start point P _sX is substituted (step S418).

Next, the control unit 104 adds 1 to the pixel number n (step S419).
Subsequently, the control unit 104 determines whether or not the pixel number n is smaller than the total number of pixels of the recorded image (step S420).

If it is determined in step S420 that the pixel number n is smaller than the total number of pixels of the recorded image (true) (step S420; Yes), the process proceeds to step S411 again, and the processes in steps S411 to S420 are repeated. .
If it is determined in step S420 that the pixel number n is equal to or greater than the total number of pixels of the recorded image (false) (step S420; No), it is determined whether or not t _n = Ttem at that time (step S421).

If it is determined in step S421 that t _n = Ttem at that time (step S421; Yes), the process proceeds to step S6 (step S61).
If it is determined in step S421 that t _n ≠ Ttem at that time (false) (step S421; No), the waiting time Wait = T−t _n−1 is set (step S422), and the process is performed in step S6 (step S421). The process proceeds to S61).

  Subsequently, the control unit 104 controls the laser head unit 102 and the driving unit 103 to repeat irradiation of the start point Ps1 to the end point Pf1 of the sub recording area N times (step S61), and start the sub recording area Ps2 to Ps2. Irradiation of the end point Pf2 is repeated N times (step S62),..., Irradiation of the sub-recording area start point PsX to end point PfX is repeated N times (steps S6X) to PfX), and a variable for specifying the recording cycle T It is determined whether or not tem = Cn (= number of types of coloring layers) (step S7).

If it is determined in step S7 that the variable tem <Cn is satisfied (step S7; No), the process has not yet been completed. Therefore, the control unit 104 adds 1 to the variable tem, and starts points Ps1 to PsX and The end points Pf1 to PfX are initialized (step S8), the process again proceeds to step S5, the process proceeds to the next sub-recording area process, and the same process is repeated thereafter.
If it is determined in step S7 that the variable tem = Cn (step S7; Yes), the process ends.

FIG. 13 is an explanatory diagram of the effect of the second modification.
According to the second modification, as shown in FIG. 13, a plurality of sub-recording areas 53, 54,... Are determined for each pixel, and recording is performed at the same period for each sub-recording area 53, 54,. Therefore, even if the scanning speeds of the recording pixels and the non-recording pixels (idle pixels) are different, irradiation can be repeatedly performed in accordance with the cycle Ttem, and an area that can be recorded in the cycle Ttem can be recorded simultaneously. is there. Therefore, the total recording time can be greatly shortened while stabilizing the color development state, and the productivity of recording can be improved.

[4.3] Third Modification As in the second modification, the third modification employs a configuration in which a plurality of recording dots (pixels) are recorded within a predetermined recording time. It is a modification in the case of shortening the total recording time until the end of the image recording process.

The difference from the second modification is that the designation of the sub-recording area that can be recorded with the period Ttem is not performed in units of pixels, but is performed in rows at regular intervals.
In the third modified example, in order to develop the color developing layer to be recorded, the time that the heat applied to the surface of the recording medium by laser irradiation is transmitted to the color developing layer is used to advance the recording of other pixels during that time. The number of lines that can be recorded during the optimum irradiation repetition period is calculated, and the lines to be recorded as one recording area are arranged at a constant interval in the entire desired recording image, which is used as one unit recording area.
The sub-recording area calculation is performed in step S5 in FIG. 10 as in the second modification.

FIG. 14 is a detailed process flowchart of a calculation process of a plurality of areas that can be recorded in the cycle Ttem in the third modification.
FIG. 15 is an explanatory diagram for determining the sub recording area in the third modification.
First, the control unit 104 assumes that one line in the width direction of the image corresponding to the input print image data 50 is a print pixel, and proceeds when the line advances at the laser scanning speed of the print pixel by one line in the width direction. The required time is calculated and set to A (step S431).

Next, the control unit 104 calculates how many lines can be recorded in the width direction in the cycle Ttem, and sets B (integer part) + C (decimal part) (step S432).
Subsequently, the control unit 104 determines whether or not the decimal part C = 0 (step S433).

If it is determined in step S433 that C = 0 (true) (step S433; Yes), the number of lines that can be recorded in the cycle Ttem is reduced by 1 as B = B-1 (step S434), and the process proceeds to step S436. . This is to secure time for _running from the end point P _fX of each recording area to the start point P _sX of the recording area.

  If it is determined in step S433 that C ≠ 0 (false) (step S433; No), the control unit 104 sets B = B (step S435), shifts the process to step S436 without change, and records it. Calculate the number of pixels (total number of lines to be recorded) in the height direction of the image, calculate the quotient divided by the number of lines B that can be recorded with the period Ttem, and D (integer part) + E (decimal part) (Step S436).

  Next, the control unit 104 determines whether X indicating the unit recording area is smaller than B × E, and determines whether or not the final row of the sub recording area is outside the desired recording image. Determination is made (S437).

  If it is determined in step S437 that X indicating the unit recording area is smaller than B × E (true) (step S437; Yes), B = B is not changed (step S438), and the process is performed. The process proceeds to step S440.

  If it is determined in step S437 that X indicating the unit recording area is greater than or equal to B × E (false) (step S437; No), the control unit 104 sets B = B-1 and the waiting time. Wait = A + AC (step S439).

Next, the control unit 104 may calculate whether the start point _{P sX} and the end point _{P fX} of X-th sub recording areas is what the second pixel, and stores the end point _{P fX} the start point _{P sX} (step S440).
Next, the control unit 104 sets X = X + 1 (step S441) to perform processing for the next sub-recording area, and determines whether X is smaller than a value obtained by adding 1 to the last recording area number D. (Step S442).

  If it is determined in step S442 that X is smaller than the value obtained by adding 1 to the last recording area number D (true) (step S442; Yes), the process returns to step S437, and steps S437 to S437 are performed. The process of S442 is repeated.

  If it is determined in step S442 that X is equal to or greater than the value obtained by adding 1 to the last recording area number D (false) (step S442; No), the process proceeds to step S6 (step S61). Processing similar to that of the second modification is performed.

  According to the third modified example, as shown in FIG. 15, a plurality of sub-recording areas 53, 54,... Are determined in units of rows (as a group of every other row in FIG. 15). Since recording is performed with a larger number of lines, when recording is performed in the same cycle for each of the sub-recording areas 53, 54,..., The influence of heat remaining when recording adjacent lines or neighboring lines is reduced. Thus, the total recording time can be greatly shortened while stabilizing the color development state, and the productivity of recording can be improved.

[4.4] Fourth Modification FIG. 16 is an explanatory diagram of the effect of the fourth modification.
In the second modification or the third modification described above, the sub-recording area is set in units of pixels or rows. However, as shown in FIG. 16, the sub-recording area is divided into the width direction and the height direction. It is also possible to configure to set 53 to 57.

[4.5] Fifth Modification FIG. 17 is an explanatory diagram of a fifth modification.
In the above description, the spot diameter of the laser beam at the time of image recording has not been described in detail. However, the spot control unit 102A controls the optical system to control the spot diameter of the laser beam on the recording medium surface. Further, the color developing layer that is more distant from the surface (in the case of the above embodiment, the high temperature coloring layer 17 → the medium temperature coloring layer 15 → the low temperature coloring layer 13). It is possible to make the size of the recording dots (minimum color development area) in the layer constant.

More specifically, in the case of the example of FIG. 17, the spot diameter SPh at the time of recording of the high temperature coloring layer 17 shown in FIG. 17 (c) so that the diameter of the coloring region becomes equal> the intermediate temperature shown in FIG. 17 (b). Spot diameter SPm at the time of recording of the coloring layer 15> spot diameter SPl at the time of recording of the low temperature coloring layer 13 shown in FIG.
With this configuration, it is possible to record a full color image with higher resolution.

[4.6] Sixth Modification In the above description, the irradiation time of the laser beam LB is controlled in an analog manner, but the laser beam is oscillated in a pulsed manner, and the irradiation time of the laser beam LB is digitally expressed by the number of pulses. It is also possible to configure so as to be controlled.

[4.7] Seventh Modification In addition to the above-described irradiation control of the laser beam LB, the recording medium 10 itself by air blowing, heating of the recording stage 101, or cooling, or the surrounding environmental temperature control is performed to further increase the recording speed. It is also possible to improve.

[4.8] Eighth Modification In the above description, the case where there are three color-developing layers has been described, but the present invention can be similarly applied to the case of two layers and the case of four or more layers.

[4.9] Ninth Modification The control unit 104 of the laser recording apparatus 100 of the present embodiment includes a control device such as a CPU, a storage device such as a ROM (Read Only Memory) and a RAM, an HDD, a CD drive device, and the like. The external storage device, a display device such as a display device, and an input device such as a keyboard and a mouse, and has a hardware configuration using a normal computer.

  A program executed by the control unit 104 of the laser recording apparatus 100 of the present embodiment is a file in an installable format or an executable format, and is a CD-ROM, a flexible disk (FD), a CD-R, a DVD (Digital Versatile Disk). And the like recorded on a computer-readable recording medium.

  Further, the program executed by the control unit 104 of the laser recording apparatus 100 according to the present embodiment may be provided by being stored on a computer connected to a network such as the Internet and downloaded via the network. good. Further, the program executed by the control unit 104 of the laser recording apparatus 100 of the present embodiment may be provided or distributed via a network such as the Internet.

  Further, the program of the control unit 104 of the laser recording apparatus 100 of the present embodiment may be configured to be provided by being incorporated in advance in a ROM or the like.

  As described above, the laser recording apparatus according to the embodiment includes the heat-sensitive materials having different color development threshold temperatures, and the threshold temperature of the heat-sensitive material included through the intermediate layer that performs heat insulation and heat transfer. A laser recording apparatus that performs recording by irradiating the laser beam on a recording medium including a plurality of heat-sensitive recording layers laminated from the surface side irradiated with the laser beam so as to be high, wherein the threshold temperature is high The power density of the laser beam is relatively increased as the recording is performed on the thermal recording layer, and the recording target is irradiated with the laser beam as the irradiation time is effectively longer as the recording is performed on the thermal recording layer where the threshold temperature is lower. Although the control part which performs the recording with respect to the said thermosensitive recording layer was provided, the following aspects are also possible as an aspect of embodiment.

In the first aspect, the control unit divides a recording area into a plurality of sub-recording areas when performing recording by irradiating the laser beam a plurality of times at the same recording position, and the same thermal recording layer You may make it control so that the irradiation period of the said laser beam in each said sub-recording area becomes the same.
Moreover, in a 2nd aspect, it has the spot control part which controls the spot diameter of the said laser beam, The said control part is the said via the said spot control part according to the lamination position of the said thermosensitive recording layer of recording object. The spot diameter of the laser beam may be changed.

  Moreover, in the third aspect, the control unit increases the spot diameter as the thermal recording layer is laminated on the surface side irradiated with the laser beam, and the recording is formed on the plurality of thermal recording layers. You may make it make the magnitude | size of a dot constant.

  In the fourth aspect, the wavelength of the laser beam may be 800 to 12000 nm.

  In the fifth aspect, the thermosensitive recording layer of the recording medium is provided for each of the three primary colors that perform color expression by subtractive color mixing, and the control unit forms a color image based on input image data. You may do it.

  Further, each of the heat-sensitive materials having different color development threshold temperatures is included, and from the surface side irradiated with laser light so that the threshold temperature of the heat-sensitive material included through the intermediate layer that performs heat insulation and heat transfer is increased. A method performed by a laser recording apparatus that performs recording by irradiating the laser beam onto a recording medium having a plurality of laminated thermal recording layers, wherein the recording temperature of the thermal recording layer is higher when the threshold temperature is higher. The process of setting the power density of laser light relatively high, and the heat-sensitive recording layer to be recorded by irradiating the laser light as an irradiation time that is effectively longer as the recording time of the heat-sensitive recording layer having a lower threshold temperature It is also possible to adopt a method comprising:

[5] Fourth Embodiment By the way, the laser recording methods of the first to third embodiments described above are recording methods in which each layer is selectively colored by controlling the laser irradiation conditions. In the method according to the third to third embodiments, when recording with three primary colors, recording is performed for each color. Therefore, at least three scans are necessary, and in the case of color mixing, the color to be mixed is determined. Since the number of scans is the same as the number of times, it takes a long time to record.

  Therefore, in the fourth embodiment, the laser power density, the irradiation time, and the irradiation cycle are controlled to specific conditions as parameters, and two or three colors adjacent in the direction perpendicular to the laser incident direction are simultaneously developed. Thus, the embodiment aims to shorten the recording time by causing the number of scans when recording mixed colors to occur.

  In the following, when recording a pixel that mixes multiple colors of the three primary colors on a recording medium in which three color layers of different primary temperatures are laminated, the laser power density, irradiation time, and irradiation cycle are appropriately controlled. By doing so, a method for selectively coloring a plurality of (two or three kinds of coloring layers in the fourth embodiment) colored layers that are sequentially different in the lamination direction according to the coloring temperature will be described. .

  In place of controlling the laser power density, irradiation time, and irradiation cycle, the laser power, pulse width, scanning speed, delay time (interval time) at repeated irradiation, spot diameter, and defocus amount are appropriately controlled. It is also possible to configure.

FIG. 18 is an explanatory diagram of the coloring principle in the multi-color coloring according to the fourth embodiment.
That is, FIG. 18A is a diagram for explaining the principle when the low temperature coloring layer 13 and the medium temperature coloring layer 15 are colored in parallel.
FIG. 18B is a diagram for explaining the principle when the medium temperature coloring layer 15 and the high temperature coloring layer 17 are colored in parallel.

FIG. 18C is a diagram for explaining the principle when the low temperature coloring layer 13, the medium temperature coloring layer 15, and the high temperature coloring layer 17 are colored in parallel.
As shown in FIG. 18A, when the recording laser beam LB is irradiated under a specific condition, the color development target region CL of the low temperature color development layer 13 exceeds the color development threshold temperature ThL, and the color development of the intermediate temperature color development layer 15 occurs. By preventing the target area CM from exceeding the color development threshold temperature ThM and preventing the high temperature color development layer 17 from exceeding the color development threshold temperature ThH, the low / medium temperature color development layer color mixture can be performed.

  Similarly, as shown in FIG. 18B, when the recording laser beam LB is irradiated under a specific condition, the color development target region CM of the intermediate temperature color development layer 15 exceeds the color development threshold temperature ThM, and the high temperature color development layer. By preventing the 17 color development target areas CH from exceeding the color development threshold temperature ThH and preventing the low temperature color development layer 13 from exceeding the color development threshold temperature ThL, the middle / high temperature color development layer can be mixed.

  Further, as shown in FIG. 18C, when the recording laser beam LB is irradiated under a specific condition, the coloring target region CL of the low-temperature coloring layer 13 exceeds the coloring threshold temperature ThL, and the medium-temperature coloring layer 15 By setting the color development target area CM to exceed the color development threshold temperature ThM and the color development target area CH of the high temperature color development layer 17 to exceed the color development threshold temperature ThH, low, medium, and high temperature color development layer mixing can be performed.

FIG. 19 is an explanatory diagram of an energy-time relationship in which each coloring layer in the fourth embodiment exceeds a threshold temperature for coloring.
In FIG. 19, for each of the coloring layers 13, 15, and 17, a threshold reaching time curve is shown in which the coloring target regions of the coloring layers 13, 15, and 17 reach the coloring threshold temperature.

  Specifically, the energy-time curve to reach the color development threshold temperature corresponding to the low-temperature color development layer 13 is a threshold arrival time curve LL indicated by a broken line, and in FIG. 19, the temperature is low in the region above the threshold arrival time curve LL. It shows that the coloring layer 13 is colored.

  Further, the energy-time curve for the color development threshold temperature corresponding to the medium temperature color development layer 15 is the threshold value arrival time curve LM indicated by a one-dot chain line, and the medium temperature color development layer in the region above the threshold value arrival time curve LM in FIG. 15 indicates color development.

  Furthermore, the energy-time curve to the color development threshold temperature corresponding to the high temperature color development layer 17 is a threshold arrival time curve LH indicated by a solid line, and in FIG. 19, the high temperature color development layer 17 is in the region above the threshold arrival time curve LH. It shows that color develops.

Thus, the left end is defined by the threshold arrival time curve LL, the lower end is defined by the threshold arrival time curve LM, in the region A _LM right end is defined by the threshold arrival time curve LH, low-temperature color-forming layer 13 and the medium temperature color-forming layer 15 It shows that color develops.

In the region A _MH where the left end is defined by the threshold arrival time curve LH, the lower end is defined by the threshold arrival time curve LM, and the upper end is defined by the threshold arrival time curve LL, the intermediate temperature coloring layer 15 and the high temperature coloring layer 17 are formed. Color develops.
Further, in the region A _LMH where the left end is defined by the threshold arrival time curve LH and the lower end is defined by the threshold arrival time curve LL, it indicates that all of the low temperature coloring layer 13, the medium temperature coloring layer 15 and the high temperature coloring layer 17 are colored. ing.

In FIG. 19, the left end is defined by the threshold arrival time curve LL, area A _L where the right end is defined by the threshold arrival time curve LM, only the low-temperature color-forming layer 13 described in the first to third embodiments Indicates that the region is colored. Similarly defined upper end, in threshold arrival time curve LL, the lower end is defined by the threshold arrival time curve LM, the area A _M of the right end is defined by the threshold arrival time curve LH, in the first to third embodiments The region A _H in which only the medium temperature coloring layer 15 described is a color developing region, the upper end is defined by the threshold arrival time curve LM, and the lower end is defined by the threshold arrival time curve LH is the first to second embodiments. Only the high-temperature coloring layer 17 described in the third embodiment is a colored area.

Here, an example of laser irradiation conditions will be described.
FIG. 20 is an explanatory diagram of an example of laser irradiation conditions.
In FIG. 20, the function of energy E giving the (low temperature) threshold arrival time curve LL shown in FIG. 19 is Tl (E), and the function of energy E giving the (medium temperature) threshold arrival time curve LM is Tm (E) [ The unit is time], the function of the energy E giving the (high temperature) threshold arrival time curve LH is Th (E), and the time for actually applying energy is T (E), as shown in FIG. By controlling the laser irradiation, it is possible to cause a plurality of color forming layers to perform color development in parallel.

More specifically, when the medium temperature coloring layer 15 and the high temperature coloring layer 17 are colored,
T (E) <Tl (E) and T (E)> Tm (E) and T (E)> Th (E)
It is necessary to satisfy.

Next, a specific configuration example of the recording medium 10 will be described.
FIG. 21 is an explanatory diagram of a specific configuration example of the recording medium.
The substrate 12 constituting the recording medium 10 has a thickness of, for example, 100 μm, and a thermal conductivity ratio of, for example, 0.01 to 5.00 W / m / K.

The low-temperature coloring layer 13 has a thickness of, for example, 1 to 10 μm, and a thermal conductivity ratio of, for example, 0.1 to 10 W / m / K.
Moreover, about the 1st spacer 14, as thickness, it is 7-100 micrometers, for example, and thermal conductivity ratio shall be 0.01-1 W / m / K, for example.

The intermediate temperature coloring layer 15 has a thickness of, for example, 1 to 10 μm, and a thermal conductivity ratio of, for example, 0.1 to 10 W / m / K.
Moreover, about the 2nd spacer 16, as thickness, it is 1-10 micrometers, for example, and thermal conductivity ratio shall be 0.01-1 W / m / K, for example.

Moreover, about the high temperature coloring layer 17, as thickness, it is 0.5-5 micrometers, for example, and thermal conductivity ratio shall be 0.1-10 W / m / K, for example.
Moreover, about the protective layer 18, as thickness, it is 0.5-5 micrometers, for example, and thermal conductivity ratio shall be 0.01-1 W / m / K, for example.

[5.1] First Aspect First, a first aspect of the fourth embodiment will be described.
FIG. 22 is an explanatory diagram of a coloring method using a plurality of colors mixed in the first aspect.
In FIG. 22, laser light is irradiated when the low temperature coloring layer 13 is a cyan (C) coloring layer, the medium temperature coloring layer 15 is a magenta (M) coloring layer, and the high temperature coloring layer 17 is a yellow (Y) coloring layer. The temperature change of each of the coloring layers 13, 15, and 17 in the case of the above will be described.
In this case, the rate of change in temperature is set by setting (changing) the power density of the laser according to the combination of the coloring layers to be colored.

First, a case where blue (B) is colored will be described.
FIG. 22A shows the temperature change rate when the cyan color forming layer 13 which is the low temperature color forming layer 13 and the magenta color forming layer 15 which is the medium temperature color forming layer 15 are colored, and the laser beam is irradiated to blue (B). It is a temperature-time curve in the case of making it color.
As shown in FIG. 22A, the magenta color forming layer which is the intermediate temperature color forming layer 15 starts color development at time t11.

  Then, a time t12 at which the cyan coloring layer that is the low-temperature coloring layer 13 starts color development (blue starts coloring at this time) elapses and a time t13 immediately before the yellow coloring layer that is the high-temperature coloring layer 17 develops color. By irradiating the laser beam LB until any time of the time TCM until the time is reached and stopping the irradiation, blue (B) can be developed.

Next, a case where red (R) is colored will be described.
FIG. 22B shows the temperature change rate in the case where the magenta coloring layer as the medium temperature coloring layer 15 and the yellow coloring layer as the high temperature coloring layer 17 are colored, irradiating with laser light, and red (R). It is a temperature-time curve in the case of making it color.

As shown in FIG. 22B, the magenta color forming layer which is the medium temperature color forming layer 15 starts color development at time t14.
Then, the time t15 when the yellow color forming layer which is the high temperature color forming layer 17 starts color development (red starts color development at this time) and the time t16 immediately before the cyan color forming layer which is the low temperature color forming layer 13 develops color is passed. By irradiating the laser beam LB until any time of the time TMY until reaching, and stopping the irradiation, red (R) can be developed.

Next, a case where black (K) is colored will be described.
FIG. 22C shows the temperature change rate when all of the cyan coloring layer as the low temperature coloring layer 13, the magenta coloring layer as the medium temperature coloring layer 15, and the yellow coloring layer as the high temperature coloring layer 17 are colored. FIG. 5 is a temperature-time curve when laser light is irradiated to develop black (K).
As shown in FIG. 22 (c), the yellow coloring layer, which is the high-temperature coloring layer 17, starts coloring at time t17.

Then, a time t18 at which the magenta coloring layer as the medium temperature coloring layer 15 starts color development (red starts coloring at this time) passes, and at a time t19 at which the cyan coloring layer as the low temperature coloring layer 13 develops color. When it reaches, black begins to develop color.
Therefore, by irradiating the laser beam LB until an appropriate time after the time t19 and stopping the irradiation, black (K) can be developed.

FIG. 23 is an explanatory diagram of a single color development method.
Also in FIG. 23, laser light is irradiated when the low temperature coloring layer 13 is a cyan (C) coloring layer, the medium temperature coloring layer 15 is a magenta (M) coloring layer, and the high temperature coloring layer 17 is a yellow (Y) coloring layer. The temperature change of each of the coloring layers 13, 15, and 17 in the case of the above will be described.
Also in this case, the rate of change of temperature is set by setting (changing) the power density of the laser according to the combination of the coloring layers to be colored as in the case of FIG.

First, a case where cyan (C) is colored alone will be described.
FIG. 23A shows a temperature-time curve when a cyan color forming layer 13 which is a low temperature color developing layer 13 is set to a temperature change rate when color is developed alone, and laser light is irradiated to develop cyan (C). It is.
As shown in FIG. 23A, the cyan color forming layer which is the low temperature color developing layer 13 starts color development at time t21.

  Then, by irradiating the laser beam LB until any time in the time TC until the time t22 immediately before the magenta coloring layer which is the medium temperature coloring layer 15 is colored, cyan (C) Can be colored independently.

Next, a case where magenta (M) is colored alone will be described.
FIG. 23B shows a temperature-time curve when magenta (M) is colored by irradiating a laser beam with the temperature change rate when the magenta coloring layer that is the medium temperature coloring layer 15 is colored alone. It is.

As shown in FIG. 23 (b), the magenta coloring layer, which is the intermediate temperature coloring layer 15, starts coloring at time t22.
Then, by irradiating the laser beam LB to any time in the time TM until the time t23 immediately before the yellow color forming layer 17 which is the high temperature color forming layer 17 starts color development, and stopping the irradiation, magenta ( M) can be developed alone.

Next, a case where yellow (Y) is colored will be described.
FIG. 23C is a temperature-time curve when yellow (Y) is colored by irradiating a laser beam with the temperature change rate when the yellow coloring layer is colored alone.
As shown in FIG. 23 (c), the yellow coloring layer, which is the high temperature coloring layer 17, starts coloring at time t24.

  Then, the laser beam LB is irradiated until any time in the time TY until the time t25 immediately before the magenta coloring layer 15 which is the intermediate temperature coloring layer 15 starts color development, and the irradiation is stopped. Y) can be colored independently.

Next, the operation of the first mode of the fourth embodiment will be described.
FIG. 24 is an operation flowchart of the first aspect of the fourth embodiment.
First, when the recording image data is input (step S11), the control unit 104 divides (converts) the recording image data into RGB data (step S12).

Next, the control unit 104 binarizes the converted R (red) data, G (green) data, and B (blue) data (step S13).
Then, the control unit 104 converts the binarized RGB data of each pixel into CMYRBK data (step S14). That is, the data is converted into data represented by cyan (C), magenta (M), yellow (Y), red (R), blue (B), and black (K). Here, green (G) is not included in the case of the fourth embodiment. The cyan coloring layer as the low temperature coloring layer 13 and the yellow coloring layer as the high temperature coloring layer 17 are interposed via the spacer layer. This is because simultaneous color development cannot be performed because they are not stacked adjacent to each other.

  Subsequently, the control unit 104 controls the laser head unit 102 and the driving unit 103 to perform cyan (C), magenta (M), yellow (Y), red (R), blue (B), and black (K). Each color is developed to record an image.

  Here, the process of converting the binarized RGB data of each pixel into CMYRBK data (step S14) will be described in detail.

FIG. 25 is a flowchart of the conversion process into CMYRBK data.
In the process of step S14, the control unit 104 first determines RGB data (a combination of binarized data) of each pixel (step S141).

Subsequently, the control unit 104 performs processing for conversion into CMYRBK data, which is recording data, based on the combination of the binarized data of RGB data (step S142).
Specifically, the control unit 104, when the combination of binarized data of RGB data is (0, 1, 1), that is, (R, G, B) = (0, 1, 1), The CMYRBK data is set as follows (step S1421).
(R, G, B) = (0, 1, 1)
→ (C, M, Y, R, B, K) = (1, 0, 0, 0, 0, 0)

Similarly, when the combination of binarized data of RGB data is (1, 0, 1), that is, (R, G, B) = (1, 0, 1), the control unit 104 determines CMYRBK data. Is set as follows (step S1422).
(R, G, B) = (1, 0, 1)
→ (C, M, Y, R, B, K) = (0, 1, 0, 0, 0, 0)

In addition, when the combination of binarized data of RGB data is (1, 1, 0), that is, (R, G, B) = (1, 1, 0), the control unit 104 reduces the CMYRBK data to the following. (Step S1423).
(R, G, B) = (1, 1, 0)
→ (C, M, Y, R, B, K) = (0, 0, 1, 0, 0, 0)

In addition, when the combination of the binarized data of RGB data is (1, 1, 0), that is, (R, G, B) = (1, 0, 0), the control unit 104 reduces the CMYRBK data to the following. (Step S1424).
(R, G, B) = (1, 0, 0)
→ (C, M, Y, R, B, K) = (0, 0, 0, 1, 0, 0)

Further, the control unit 104 determines the CMYRBK data as follows when the combination of binarized data of RGB data is (0, 1, 0), that is, (R, G, B) = (0, 1, 0). (Step S1425).
(R, G, B) = (0, 1, 0)
→ (C, M, Y, R, B, K) = (1, 0, 1, 0, 0, 0)

In addition, when the combination of the binarized data of the RGB data is (0, 0, 1), that is, (R, G, B) = (0, 0, 1), the control unit 104 determines the CMYRBK data as follows. (Step S1426).
(R, G, B) = (0, 0, 1)
→ (C, M, Y, R, B, K) = (0, 0, 0, 0, 1, 0)

Further, the control unit 104 determines the CMYRBK data as follows when the combination of binarized data of RGB data is (0, 0, 0), that is, (R, G, B) = (0, 0, 0). (Step S1427).
(R, G, B) = (0, 0, 0)
→ (C, M, Y, R, B, K) = (0, 0, 0, 0, 0, 1)

In addition, when the combination of the binarized data of the RGB data is (1, 1, 0), that is, (R, G, B) = (1, 1, 1), the control unit 104 reduces the CMYRBK data to the following. (Step S1428).
(R, G, B) = (1,1,1)
→ (C, M, Y, R, B, K) = (0, 0, 0, 0, 0, 0)
This is because (R, G, B) = (1, 1, 1) represents white, so that there is no need for recording (printing).

Then, the control unit 104 records the CMYRBK data with “1” in the CMYRBK data as a recording (printing) pixel and “0” as a non-recording (non-printing) pixel (step S143).
As described above, since recording is performed, full-color recording can be performed in a short time compared to the case where all recording is performed in a single color.

[5.1.1] Modified Example of First Aspect of Fourth Embodiment FIG. 26 is an operation flowchart of a modified example of the first aspect of the fourth embodiment.
In FIG. 26, the same parts as those in FIG. 25 are denoted by the same reference numerals. 26 differs from the first mode in FIG. 25 in that binarized RGB data is converted into CMY data for processing.

  According to the modification of the first mode of the fourth embodiment, when the recording image data is input (step S11), the control unit 104 divides (converts) the recording image data into RGB data (step S12).

Next, the control unit 104 binarizes the converted R (red) data, G (green) data, and B (blue) data (step S13).
Then, the control unit 104 converts the binarized RGB data of each pixel into CMYRBK data (step S14).

  Subsequently, the control unit 104 controls the laser head unit 102 and the driving unit 103 to perform cyan (C), magenta (M), yellow (Y), red (R), blue (B), and black (K). Each color is developed to record an image.

Here, the process of converting the binarized RGB data of each pixel into CMYRBK data (step S14) will be described in detail.
In the process of step S14, the control unit 104 first converts RGB data into CMY data (step S141A).

Subsequently, the control unit 104 determines CMY data (a combination of the binarized data) of each pixel (step S141B).
Subsequently, the control unit 104 performs processing for conversion into CMYRBK data, which is recording data, based on the combination of the binarized data of CMY data (step S142A).

Specifically, when the combination of the binarized data of CMY data is (1, 0, 0), that is, (C, M, Y) = (1, 0, 0), the control unit 104 The CMYRBK data is set as follows (step S1421).
(C, M, Y) = (1, 0, 0)
→ (C, M, Y, R, B, K) = (1, 0, 0, 0, 0, 0)

Similarly, when the combination of the binarized data of CMY data is (0, 1, 0), that is, (C, M, Y) = (0, 1, 0), the control unit 104 determines the CMYRBK data. Is set as follows (step S1422).
(C, M, Y) = (0, 1, 0)
→ (C, M, Y, R, B, K) = (0, 1, 0, 0, 0, 0)

Further, the control unit 104 determines the CMYRBK data as follows when the combination of the binarized data of the CMY data is (0, 0, 1), that is, (C, M, Y) = (0, 0, 1). (Step S1423).
(C, M, Y) = (0, 0, 1)
→ (C, M, Y, R, B, K) = (0, 0, 1, 0, 0, 0)

Further, the control unit 104 determines the CMYRBK data as follows when the combination of the binarized data of the CMY data is (0, 1, 1), that is, (C, M, Y) = (0, 1, 1). (Step S1424).
(C, M, Y) = (0, 1, 1)
→ (C, M, Y, R, B, K) = (0, 0, 0, 1, 0, 0)

In addition, when the combination of the binarized data of CMY data is (1, 0, 1), that is, (C, M, Y) = (1, 0, 1), the control unit 104 determines the CMYRBK data as follows. (Step S1425).
(C, M, Y) = (1, 0, 1)
→ (C, M, Y, R, B, K) = (1, 0, 1, 0, 0, 0)

In addition, when the combination of binarized data of CMY data is (1, 1, 0), that is, (C, M, Y) = (1, 1, 0), the control unit 104 reduces the CMYRBK data to (Step S1426).
(C, M, Y) = (1, 1, 0)
→ (C, M, Y, R, B, K) = (0, 0, 0, 0, 1, 0)

In addition, when the combination of the binarized data of CMY data is (1, 1, 1), that is, (C, M, Y) = (1, 1, 1), the control unit 104 reduces the CMYRBK data to the following. (Step S1427).
(C, M, Y) = (1, 1, 1)
→ (C, M, Y, R, B, K) = (0, 0, 0, 0, 0, 1)

Further, the control unit 104 determines the CMYRBK data as follows when the combination of the binarized data of the CMY data is (0, 0, 0), that is, (C, M, Y) = (0, 0, 0). (Step S1428).
(C, M, Y) = (0, 0, 0)
→ (C, M, Y, R, B, K) = (0, 0, 0, 0, 0, 0)
This is because (C, M, Y) = (0, 0, 0) represents white, so that there is no need for recording (printing).

Then, the control unit 104 records the CMYRBK data with “1” in the CMYRBK data as a recording (printing) pixel and “0” as a non-recording (non-printing) pixel (step S143).
Since recording is performed as described above, full-color recording can be performed in a shorter time than in the case of recording all in a single color also in this modification.

[5.1.2] Second Aspect of Fourth Embodiment Next, the operation of the second aspect of the fourth embodiment will be described.
FIG. 27 is an operation flowchart of the second mode of the fourth embodiment.
First, when recording image data in the RGB data format is input (step S21), the control unit 104 converts the RGB data into CMY data (step S22).

Next, the control unit 104 binarizes the converted C (cyan) data, M (magenta) data, and Y (yellow) data (step S23).
Then, the control unit 104 converts the binarized CMY data of each pixel into CMYRBK data (step S24). That is, the data is converted into data represented by cyan (C), magenta (M), yellow (Y), red (R), blue (B), and black (K).

  Subsequently, the control unit 104 controls the laser head unit 102 and the driving unit 103 to perform cyan (C), magenta (M), yellow (Y), red (R), blue (B), and black (K). Each color is developed and an image is recorded (step S25).

  Here, the process of converting the binarized CMY data of each pixel into CMYRBK data (step S24) will be described in detail.

FIG. 28 is a flowchart of conversion processing into CMYRBK data.
In FIG. 28, the same parts as those in FIG. 26 are denoted by the same reference numerals, and the detailed description thereof is incorporated.
In the process of step S24, the control unit 104 first determines CMY data (a combination of binarized data) of each pixel (step S241).

Subsequently, the control unit 104 performs processing for conversion into CMYRBK data that is recording data based on the combination of the binarized data of the CMY data (step S242).
And the process of step S1421-step S1425 and step S143 is performed similarly to the modification of the 1st aspect of 4th Embodiment.

  As described above, since the second mode of the fourth embodiment performs recording, full-color recording can be performed in a shorter time in the second mode of the fourth embodiment than in the case of recording all in a single color. .

[6] Fifth Embodiment Next, a fifth embodiment will be described.

FIG. 29 is an explanatory diagram of a schematic configuration of a recording medium used in the fifth embodiment.
As shown in FIG. 1, the recording medium 10 </ b> A has a low-temperature coloring layer 13, a first spacer layer 14, a medium-temperature coloring layer 15, a second spacer layer 16, a high-temperature coloring layer 17, a protective layer 18, a release layer on a substrate 12. The layer 191 and the light / heat conversion layer 192 are laminated in this order. Here, the substrate 12, the low temperature coloring layer 13, the first spacer layer 14, the intermediate temperature coloring layer 15, the second spacer layer 16, the high temperature coloring layer 17, and the protective layer 18 are the same as those in the above embodiments.

In the above configuration, the peeling layer 191 is a layer for peeling the light / heat conversion layer 192 after the end of recording.
The light / heat conversion layer 192 is a layer for absorbing visible light and converting it into thermal energy. In order to efficiently absorb the laser LB, a pigment or dye of a color including the complementary color of the laser LB is included. Preferably it is. Alternatively, it is possible to include a component such as carbon black that is black and absorbs all visible light.

  With this configuration, according to the fifth embodiment, a laser with a shorter wavelength can be used when recording with the laser LB, and the resolution is improved by reducing the minimum spot diameter during focusing. It becomes possible to achieve high definition.

[7] Sixth Embodiment In the above description, an embodiment has been described in which CMYRBK data is converted prior to image recording. In the sixth embodiment, G (green) is further added to CMYRGBK data. It is an embodiment in the case of conversion.

First, the principle of the sixth embodiment will be described.
In the above-described recording media 10 and 10A, when the laser LB is controlled at a constant power density or a constant irradiation cycle, the low temperature coloring layer 13 and the high temperature coloring layer 17 are colored, and only the intermediate temperature coloring layer 15 is formed. Control that did not cause color development could not be performed.
Therefore, in the sixth embodiment, the power density, irradiation period, irradiation time, and the like of the laser LB are modulated so that only the intermediate temperature coloring layer 15 is not colored.

FIG. 30 is an explanatory diagram of recording control according to the sixth embodiment.
Specifically, as shown in FIG. 30, by changing the temperature of the surface layer of the recording medium 10 (the surface layer of the protective layer 18) as indicated by the temperature curve TTS, the temperature of the high temperature coloring layer 17 is changed to the temperature curve TTY. As shown in time t3, time t31 to time t32, the color of the high-temperature coloring layer 18 is made to exceed the threshold temperature ThH.
Then, between time t32 and time t34, the temperature of the surface layer of the recording medium 10 is set to a predetermined temperature between the threshold temperature ThH and the threshold temperature ThM. As a result, the temperature of the intermediate temperature coloring layer 15 becomes a predetermined temperature between the threshold temperature ThM and the threshold temperature ThC as shown in the temperature curve TTM, and the intermediate temperature coloring layer 15 does not develop color.
On the other hand, the temperature of the low temperature coloring layer 13 exceeds the threshold temperature ThL at time t33, as indicated by the temperature polarity TTC.
In parallel with this, by controlling the laser LB so that the temperature of the surface layer of the recording medium 10 becomes lower than the threshold temperature ThL at time t34, the temperature of the high temperature coloring layer 17, the temperature of the intermediate temperature coloring layer 15, and the low temperature coloring layer. 13 gradually decreases, and at time t35, the temperature of the low temperature coloring layer 13 falls below the threshold temperature ThL as indicated by the temperature polarity TTC, and the recording ends.
Since the laser LB irradiation control and the temperature control of the recording medium 10 are performed in this manner, only the intermediate temperature coloring layer 15 is not colored, and G (green) coloring can be performed.

Next, the operation of the sixth embodiment will be described.
FIG. 31 is an operation flowchart of the sixth embodiment.
First, when recording image data is input (step S31), the control unit 104 divides (converts) the recording image data into RGB data (step S32).

Next, the control unit 104 binarizes the converted R (red) data, G (green) data, and B (blue) data (step S33).
Then, the control unit 104 converts the binarized RGB data of each pixel into CMYRGBK data (step S34). That is, the data is converted into data represented by cyan (C), magenta (M), yellow (Y), red (R), green (G), blue (B), and black (K).

  Subsequently, the control unit 104 controls the laser head unit 102 and the driving unit 103 to perform cyan (C), magenta (M), yellow (Y), red (R), green (G), and blue (B). Then, an image is recorded by developing each color of black (K) (step S35).

Here, the process of converting the binarized RGB data of each pixel into CMYRGBK data (step S14) will be described in detail.
FIG. 32 is a flowchart of the conversion process into CMYRGBK data.
In the process of step S34, the control unit 104 first determines RGB data (combining binarized data) of each pixel (step S341).

Subsequently, the control unit 104 performs processing for conversion into CMYRGBK data, which is recording data, based on the combination of the binarized data of RGB data (step S342).
Specifically, the control unit 104, when the combination of binarized data of RGB data is (0, 1, 1), that is, (R, G, B) = (0, 1, 1), The CMYRGBK data is set as follows (step S3421).
(R, G, B) = (0, 1, 1)
→ (C, M, Y, R, G, B, K) = (1, 0, 0, 0, 0, 0, 0)

Similarly, when the combination of binarized data of RGB data is (1, 0, 1), that is, (R, G, B) = (1, 0, 1), the control unit 104 determines the CMYRGBK data. Is set as follows (step S3422).
(R, G, B) = (1, 0, 1)
→ (C, M, Y, R, G, B, K) = (0, 1, 0, 0, 0, 0, 0)

In addition, when the combination of the binarized data of RGB data is (1, 1, 0), that is, (R, G, B) = (1, 1, 0), the control unit 104 determines the CMYRGBK data as follows. (Step S3423).
(R, G, B) = (1, 1, 0)
→ (C, M, Y, R, G, B, K) = (0, 0, 1, 0, 0, 0, 0)

In addition, when the combination of binarized data of RGB data is (1, 1, 0), that is, (R, G, B) = (1, 0, 0), the control unit 104 determines the CMYRGBK data as follows. (Step S3424).
(R, G, B) = (1, 0, 0)
→ (C, M, Y, R, G, B, K) = (0, 0, 0, 1, 0, 0, 0)

In addition, when the combination of the binarized data of RGB data is (0, 1, 0), that is, (R, G, B) = (0, 1, 0), the control unit 104 reduces the CMYRGBK data to the following. (Step S3425).
(R, G, B) = (0, 1, 0)
→ (C, M, Y, R, G, B, K) = (0, 0, 0, 0, 1, 0, 0)

Further, the control unit 104 determines the CMYRGBK data as follows when the combination of binarized data of RGB data is (0, 0, 1), that is, (R, G, B) = (0, 0, 1). (Step S3426).
(R, G, B) = (0, 0, 1)
→ (C, M, Y, R, G, B, K) = (0, 0, 0, 0, 0, 1, 0)

Further, the control unit 104 determines the CMYRGBK data as follows when the combination of binarized data of RGB data is (0, 0, 0), that is, (R, G, B) = (0, 0, 0). (Step S3427).
(R, G, B) = (0, 0, 0)
→ (C, M, Y, R, G, B, K) = (0, 0, 0, 0, 0, 0, 1)

In addition, when the combination of binarized data of RGB data is (1, 1, 0), that is, (R, G, B) = (1, 1, 1), the control unit 104 sets CMYRGBK as follows: (Step S3428).
(R, G, B) = (1,1,1)
→ (C, M, Y, R, G, B, K) = (0, 0, 0, 0, 0, 0, 0)
This is because (R, G, B) = (1, 1, 1) represents white, so that there is no need for recording (printing).

Then, the control unit 104 records the CMYRGBK data with “1” in the CMYRGBK data as a recording (printing) pixel and “0” as a non-recording (non-printing) pixel (step S343).
As described above, since recording is performed, full-color recording including green (G) can be performed in a short time compared to the case of recording all in a single color.

[7.1] First Mode of Sixth Embodiment FIG. 33 is an operation flowchart of the first mode of the fourth embodiment.
In FIG. 33, the same parts as those in FIG. 32 are denoted by the same reference numerals. 33 is different from the first mode in FIG. 32 in that binarized RGB data is converted into CMY data for processing.
According to the modification of the first mode of the sixth embodiment, when the recording image data is input (step S31), the control unit 104 divides (converts) the recording image data into RGB data (step S32).

Next, the control unit 104 binarizes the converted R (red) data, G (green) data, and B (blue) data (step S33).
Then, the control unit 104 converts the binarized RGB data of each pixel into CMYRGBK data (step S34).

  Subsequently, the control unit 104 controls the laser head unit 102 and the driving unit 103 to perform cyan (C), magenta (M), yellow (Y), red (R), green (G), and blue (B). In addition, an image is recorded by developing each color of black (K).

Here, the process of converting the binarized RGB data of each pixel into CMYRGBK data (step S34) will be described in detail.
In the process of step S34, first, the control unit 104 converts RGB data into CMY data (step S341A).
Subsequently, the control unit 104 determines CMY data (a combination of binarized data) of each pixel (step S341B).
Subsequently, the control unit 104 performs processing for conversion into CMYRGBK data, which is recording data, based on the combination of the binarized data of CMY data (step S342).
And the process of step S3421-step S3425 and step S343 is performed similarly to 6th Embodiment.
As described above, since the first mode of the sixth embodiment performs recording, the modified example of the first mode of the sixth embodiment also has a full color in a short time compared to the case of recording all in a single color. Can record.

[7.2] Second Aspect of Sixth Embodiment Next, the operation of the second aspect of the sixth embodiment will be described.
FIG. 34 is an operation flowchart of the second aspect of the sixth embodiment.
First, when recording image data in the RGB data format is input (step S41), the control unit 104 converts the RGB data into CMY data (step S42).

Next, the control unit 104 binarizes the converted C (cyan) data, M (magenta) data, and Y (yellow) data (step S43).
Then, the control unit 104 converts the binarized CMY data of each pixel into CMYRGBK data (step S44). That is, the data is converted into data represented by cyan (C), magenta (M), yellow (Y), red (R), green (G), blue (B), and black (K).

  Subsequently, the control unit 104 controls the laser head unit 102 and the driving unit 103 to perform cyan (C), magenta (M), yellow (Y), red (R), green (g) blue (B), and An image is recorded by developing each color of black (K) (step S45).

Here, the process of converting the binarized CMY data of each pixel into CMYRGBK data (step S44) will be described in detail.
FIG. 35 is a flowchart of the conversion process into CMYRGBK data.
In FIG. 35, the same components as those in FIG. 33 are denoted by the same reference numerals, and the detailed description thereof is cited.
In the process of step S44, first, the control unit 104 determines CMY data (a combination of binarized data) of each pixel (step S441).
Subsequently, the control unit 104 performs processing for conversion to CMYRBK data that is recording data based on the combination of the binarized data of the CMY data (step S442).
And the process of step S3421-step S3425 and step S343 is performed similarly to the 1st aspect of 6th Embodiment.
As described above, since the second aspect of the sixth embodiment performs recording, full-color recording can be performed in a shorter time in the second aspect of the sixth embodiment as compared to the case where everything is recorded in a single color. .

As described above, according to the fourth to sixth embodiments, since a plurality of colors can be developed simultaneously in parallel, the apparatus configuration is simplified while maintaining and improving the quality of the recorded image. Furthermore, full color recording can be performed in a short time.
In the above description, the three color development layers, ie, the low temperature color development layer 13, the medium temperature color development layer 15 and the high temperature color development layer 17, have been described. It is also possible to adopt a configuration in which the coloring layers are colored in parallel.

DESCRIPTION OF SYMBOLS 10, 10A Recording medium 12 Base material 13 Low temperature coloring layer 14 1st spacer layer 15 Medium temperature coloring layer 16 2nd spacer layer 17 High temperature coloring layer 18 Protective layer 21-23 Coloring area 30 Laser spot 50 Recording image data 51 Recording pixel 52 Non Recording pixels 53 to 57 Sub-recording area 100 Laser recording device 101 Recording stage 102 Laser head unit 102A Spot control unit 103 Drive unit 104 Control unit 191 Peeling layer 192 Light / heat conversion layer CT1 to CT3 Number of scans LB Laser light PDh, PDl, PDm Power density Pf1 to PfX End point Ps1 to PsX Start point SPT Spot SPh, SPl, SPm Spot diameter Th Third threshold temperature Tl First threshold temperature Tm Second threshold temperature Ttem Period Ve Laser scanning speed Vtem Laser scanning speed th, tl , Tm Recording time V1~V3 scanning speed WT1~WT3 waiting time

Claims (8)

Each of the heat-sensitive materials having different color development threshold temperatures is included, and is laminated from the surface side irradiated with laser light so that the threshold temperature of the heat-sensitive material included through the intermediate layer for heat insulation and heat transfer is increased. A laser recording apparatus that performs recording by irradiating the recording medium with a plurality of thermal recording layers with the laser beam,
The laser beam power density is relatively increased as the recording temperature of the thermosensitive recording layer having a higher threshold temperature, and the irradiation time is effectively increased as the recording time of the thermosensitive recording layer having a lower threshold temperature. Recording apparatus including a control unit that performs recording on the heat-sensitive recording layer to be recorded. The control unit slows down the scanning speed of the laser light at the same recording position as the thermosensitive recording layer has a lower threshold temperature.
The laser recording apparatus according to claim 1. The control unit increases the number of times of irradiation of the laser light at the same recording position as the thermosensitive recording layer has a lower threshold temperature.
The laser recording apparatus according to claim 1. The control unit makes the waiting time from the previous irradiation of the laser beam to the current irradiation at the same recording position longer for the thermosensitive recording layer having a lower threshold temperature,
The laser recording apparatus according to claim 1. The controller performs the recording for each thermosensitive recording layer.
The laser recording apparatus according to any one of claims 1 to 4. Each of the heat-sensitive materials having different color development threshold temperatures is included, and is laminated from the surface side irradiated with laser light so that the threshold temperature of the heat-sensitive material included through the intermediate layer for heat insulation and heat transfer is increased. A laser recording apparatus that performs recording by irradiating the recording medium with a plurality of thermal recording layers with the laser beam,
A laser recording apparatus including a control unit that performs recording by irradiating the laser beam to the same recording position of a plurality of the heat-sensitive recording layers that are stacked to simultaneously color the plurality of heat-sensitive recording layers to be colored. . The control unit controls the laser beam so as to color the plurality of heat-sensitive recording layers stacked in close proximity to each other or the plurality of heat-sensitive recording layers stacked via another heat-sensitive recording layer;
The laser recording apparatus according to claim 6. The control unit controls the power density, irradiation time, and irradiation cycle of the laser light, and simultaneously develops a plurality of thermosensitive recording layers to be colored,
The laser recording apparatus according to claim 6 or 7.

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