JP6206016B2 - Image processing method - Google Patents

Description

  The present invention relates to an image processing method.

  Conventionally, when an image is recorded on a thermoreversible recording medium and when an image recorded on the thermoreversible recording medium is erased, a contact type in which a heat source is brought into contact with the thermoreversible recording medium to heat the thermoreversible recording medium is used. It has been. As the heat source, a thermal head is usually used when recording an image, and a heat roller, a ceramic heater, or the like is used when erasing the recorded image.

  However, while the stored information is read and rewritten from a position where the RF-ID tag is separated in a non-contact manner, there is a demand for rewriting an image from a position away from the thermoreversible recording medium.

  For example, as a method for recording an image and a method for erasing the recorded image from a distant position on a thermoreversible recording medium having irregularities on the surface, a method of irradiating a laser beam is known. In addition, a laser marker is known as an apparatus that can control the position at which a thermoreversible recording medium is irradiated with laser light. When a laser marker is used to irradiate a thermoreversible recording medium with laser light, the photothermal conversion material in the thermoreversible recording medium absorbs the light and converts it into heat, recording an image on the thermoreversible recording medium, and thermoreversible. The image recorded on the recording medium can be erased.

  Generally, when erasing an image recorded on a thermoreversible recording medium, the area where the image is recorded is not necessarily the same. Scan in parallel at predetermined intervals.

  However, there is a problem that an image recorded on the thermoreversible recording medium cannot be erased in a short time.

  Patent Document 1 discloses a drawing control method in which a computer controls a drawing apparatus that draws a drawing target by irradiating a thermoreversible recording medium with a laser. At this time, the computer divides the drawing target into a plurality of lines, a drawing position determining step for determining a drawing position for drawing each of the plurality of lines on the thermoreversible recording medium, and a drawing target while reversing the drawing direction of adjacent lines. A drawing order determination step that determines the drawing order of each line of a plurality of lines so as to draw a line, and when drawing another line next to one line by reciprocating scanning on a thermoreversible recording medium, Is adjusted to be lower than the laser output for drawing the end point side of another row, or the first distance between the end point of one row and the start point of the other row is one row. An adjustment step of adjusting the drawing position so as to be longer than the second distance between the start point of the line and the end point of the other row, and a drawing command generation step of generating a drawing command reflecting the drawing position and the drawing order .

  However, it is desired to erase the image recorded on the thermoreversible recording medium in a shorter time without increasing the irradiation energy density of the laser beam.

  One embodiment of the present invention is an image processing capable of erasing an image recorded on a thermoreversible recording medium in a short time without increasing the irradiation energy density of laser light in view of the problems of the above-described conventional technology. It is an object to provide a method and an image processing apparatus.

One aspect of the present invention is an image processing method for have a step of eliminating the image by scanning the laser beam in parallel to the thermally reversible recording medium which images are recorded, the process is the laser beam the area to be scanned in parallel, divided into regions of multiple and to the direction of scanning the laser beam, erasing the image by scanning a laser beam in parallel to each of the divided plurality of regions a step of, among the plurality of regions, adjacent regions have an overlap ratio of the overlapping width of the region in contact該隣for spot diameter of the laser light is 0.20 or more and 1.6 or less.

  According to one aspect of the present invention, there is provided an image processing method and an image processing apparatus capable of erasing an image recorded on a thermoreversible recording medium in a short time without increasing the irradiation energy density of laser light. can do.

It is the schematic which shows an example of the image processing method. FIG. 2 is a schematic diagram showing a method of not dividing an image recording area in the image processing method of FIG. 1. It is the schematic which shows the other example of the image processing method. FIG. 4 is a schematic diagram showing a method of not dividing an image recording area in the image processing method of FIG. 3. It is the schematic which shows the other example of the image processing method. It is the schematic which shows the other example of the image processing method. It is the schematic which shows an example of an image processing apparatus. It is a schematic sectional drawing which shows the 1st example of the layer structure of a thermoreversible recording medium. It is a schematic sectional drawing which shows the 2nd example of the layer structure of a thermoreversible recording medium. It is a schematic sectional drawing which shows the 3rd example of a layer structure of a thermoreversible recording medium.

  Next, the form for implementing this invention is demonstrated with drawing.

  The image processing method includes an image erasing step, and may further include an image recording step.

  The image erasing step is a step of erasing an image by scanning laser light in parallel on a thermoreversible recording medium on which the image is recorded.

  At this time, in the image erasing step, a region where laser light is scanned in parallel is divided into a plurality of regions in the scanning direction of the laser light, and adjacent regions of the plurality of regions have overlap. For this reason, the image recorded on the thermoreversible recording medium can be erased in a short time without increasing the irradiation energy density of the laser beam.

Here, the irradiation energy density [mJ / mm ² ] of the laser beam is such that the laser beam output is P [W], the laser beam scanning speed is V [mm / s], and the laser beam irradiation interval is I [mm]. Then, the formula P × 1000 / (V × I)
It is represented by

  The ratio of the overlapping width of adjacent regions to the laser beam spot diameter is 0.20 to 1.6, preferably 0.20 to 1.0. If the ratio of the overlapping width of the adjacent regions to the laser beam spot diameter is less than 0.20, the image at the boundary portion between the plurality of regions will be insufficiently erased, and if it exceeds 1.6, the image will be erased. The time will be longer.

  FIG. 1 shows an example of an image processing method. FIG. 1 shows an example in which the thermoreversible recording medium 100 on which an image is recorded in the image recording area 101 is scanned in parallel with laser light to erase the image, and the scanning direction of the adjacent laser light is opposite.

  At this time, the image recording area 101 that scans in parallel with the laser light is divided into four areas 101a, 101b, 101c, and 101d in the scanning direction of the laser light, and the adjacent areas 101a, 101b, 101b, and 101c, 101c, and 101d have an overlap with an overlap width of L. Further, the scanning direction of the laser beam is the short direction of the image recording area 101.

  In the figure, the solid line and the dotted line are scanned in a state where the laser beam is irradiated (laser beam drawing line) and between adjacent laser beam drawing lines in a state where the laser beam is not irradiated. Is the behavior that has been done.

  FIG. 2 shows a method in which the image recording area 101 is not divided in the image processing method of FIG.

  In this case, when the laser beam is scanned with the laser beam irradiation energy density adjusted to an optimum condition other than the laser beam drawing line folding part, the laser beam irradiation energy density at the laser beam drawing line folding part is determined by the residual heat. Because it is affected, it becomes excessive.

  On the other hand, when the laser beam is scanned by adjusting the irradiation energy density of the laser beam at the folded portion of the laser beam drawing line to an optimum condition, the irradiation energy density at the portion other than the folded portion of the laser beam drawing line is affected by the residual heat. Because it is difficult, it is insufficient.

  Here, as in the image processing method of FIG. 1, when the image recording area 101 that scans laser beams in parallel is divided with respect to the scanning direction of the laser beams, irradiation energy other than the folded portion of the laser beam drawing lines. The density is also excessive because it is affected by the residual heat. For this reason, it is possible to increase the scanning speed of the laser beam or to increase the irradiation interval of the laser beam, and as a result, it is possible to shorten the time for erasing the image.

  FIG. 3 shows another example of the image processing method. FIG. 3 shows an example in which the thermoreversible recording medium 100 in which an image is recorded in the image recording area 101 is scanned with laser light in parallel to erase the image, and the scanning direction of the adjacent laser light is the same.

  At this time, the image recording area 101 that scans in parallel with the laser light is divided into four areas 101a, 101b, 101c, and 101d in the scanning direction of the laser light, and the adjacent areas 101a, 101b, 101b, and 101c, 101c, and 101d have an overlap with an overlap width of L. Further, the scanning direction of the laser beam is the short direction of the image recording area 101.

  In the figure, the solid line and the dotted line are scanned in a state where the laser beam is irradiated (laser beam drawing line) and between adjacent laser beam drawing lines in a state where the laser beam is not irradiated. Is the behavior that has been done.

  FIG. 4 shows a method in which the image recording area 101 is not divided in the image processing method of FIG.

  In this case, when the laser beam is scanned with the laser beam irradiation energy density adjusted to an optimum condition other than the laser beam drawing line folding part, the laser beam irradiation energy density at the laser beam drawing line folding part is determined by the residual heat. Because it is difficult to be affected by, it does not become excessive.

  Here, when the image recording area 101 is divided in the laser beam scanning direction as in the image processing method of FIG. 3, the irradiation energy density of the laser beam drawing line is affected by the residual heat. Become excessive. For this reason, it is possible to increase the scanning speed of the laser beam or to increase the irradiation interval of the laser beam, and as a result, it is possible to shorten the time for erasing the image.

  FIG. 5 shows another example of the image processing method. FIG. 5 is an example in which the thermoreversible recording medium 100 in which an image is recorded in the image recording area 101 is scanned with laser light in parallel to erase the image and the scanning direction of the adjacent laser light is the same.

  At this time, the image recording area 101 scanned in parallel with the laser light is divided into two areas 101a and 101b in the scanning direction of the laser light, and the adjacent areas 101a and 101b have an overlap width of L. Has some overlap. Further, the scanning direction of the laser beam is the short direction of the image recording area 101.

  In the figure, the solid line and the dotted line are scanned in a state where the laser beam is irradiated (laser beam drawing line) and between adjacent laser beam drawing lines in a state where the laser beam is not irradiated. Is the behavior that has been done.

  FIG. 6 shows another example of the image processing method. FIG. 6 shows an example in which the thermoreversible recording medium 100 in which an image is recorded in the image recording area 101 is scanned with laser light in parallel to erase the image, and the scanning direction of the adjacent laser light is the same.

  At this time, the image recording area 101 that scans in parallel with the laser beam is divided into six areas 101a, 101b, 101c, 101d, 101e, and 101f with respect to the direction in which the laser beam is scanned. 101b, 101b and 101c, 101c and 101d, 101d and 101e, 101e and 101f have overlap with an overlap width of L. Further, the scanning direction of the laser beam is the short direction of the image recording area 101.

  In the figure, the solid line and the dotted line are scanned in a state where the laser beam is irradiated (laser beam drawing line) and between adjacent laser beam drawing lines in a state where the laser beam is not irradiated. Is the behavior that has been done.

  The number of divisions of the image recording area 101 that scans laser beams in parallel with respect to the scanning direction of the laser beams is usually 2 to 100, and preferably 2 to 80. When the number of divisions of the image recording area 101 that scans the laser beams in parallel with respect to the scanning direction of the laser beams exceeds 100, the time for erasing the image recorded on the thermoreversible recording medium 100 becomes longer. Sometimes.

  The ratio of the length of the laser beam drawing line to the laser beam spot diameter is usually 1.5 or more. When the ratio of the length of the laser beam drawing line to the laser beam spot diameter is less than 1.5, the time for erasing the image recorded on the thermoreversible recording medium 100 may be longer.

  The scanning direction of the laser beam is preferably the short direction of the image recording area 101. As a result, the image recorded on the thermoreversible recording medium 100 can be erased in a short time.

  Note that the image recording area 101 that scans the laser beams in parallel may be divided equally or non-uniformly.

  Further, the image recording area 101 that scans in parallel with the laser beam may be further divided in a direction perpendicular to the scanning direction of the laser beam.

  The output of the laser beam irradiated when erasing the image is usually 5 W or more, preferably 7 W or more, and more preferably 10 W or more. If the output of the laser beam irradiated when erasing the image is less than 5 W, it may take time to erase the image. Further, the output of the laser beam irradiated when erasing the image is usually 200 W or less, preferably 190 W or less, and more preferably 180 W or less. If the output of the laser beam irradiated when erasing the image exceeds 200 W, the laser device may be increased in size.

  The scanning speed of the laser beam irradiated when erasing the image is usually 100 mm / s or more, preferably 200 mm / s or more, and more preferably 300 mm / s or more. If the scanning speed of the laser beam irradiated when erasing the image is less than 100 mm / s, it may take time to erase the image. Moreover, the scanning speed of the laser beam irradiated when erasing an image is usually 15000 mm / s or less, preferably 10,000 mm / s or less, and more preferably 8000 mm / s or less. If the scanning speed of the laser beam irradiated when erasing the image exceeds 15000 mm / s, it may be difficult to erase the image uniformly.

  The spot diameter of the laser beam irradiated when erasing the image is usually 0.5 mm or more, preferably 1.0 mm or more, and more preferably 2.0 mm or more. If the spot diameter of the laser beam irradiated when erasing the image is less than 0.5 mm, it may take time to erase the image. Further, the spot diameter of the laser beam irradiated when erasing the image is usually 14.0 mm or less, preferably 12.0 mm or less, and more preferably 10.0 mm or less. If the spot diameter of the laser beam irradiated when erasing an image exceeds 14.0 mm, the output may be insufficient and an image erasing failure may occur.

  Note that the image erasing step may be performed on a thermoreversible recording medium on which no image is recorded.

  The image recording step is a step of recording an image after the image is erased, before the image is erased or by heating a thermoreversible recording medium on which no image is recorded.

  A method for heating the thermoreversible recording medium is not particularly limited, and examples thereof include a non-contact heating method using a laser beam and the like, a contact heating method using a thermal head and the like. In particular, when a distribution line is assumed, a method of irradiating with laser light is preferable because even if irregularities are generated on the surface of the thermoreversible recording medium, there is little influence and recording can be performed from a remote position.

  At this time, an image may be recorded on the entire surface of the thermoreversible recording medium, or an image may be recorded by providing blank portions on the top, bottom, left and right of the thermoreversible recording medium.

  The output of the laser beam irradiated when recording an image is usually 1 W or more, preferably 3 W or more, and more preferably 5 W or more. If the output of the laser beam irradiated when recording an image is less than 1 W, it may take time to record the image. Further, the output of the laser beam irradiated when recording an image is usually 200 W or less, preferably 150 W or less, and more preferably 100 W or less. If the output of the laser beam irradiated when recording an image exceeds 200 W, the laser device may be increased in size.

  The scanning speed of the laser beam irradiated when recording an image is usually 300 mm / s or more, preferably 500 mm / s or more, and more preferably 700 mm / s or more. If the scanning speed of the laser beam irradiated when recording an image is less than 300 mm / s, it may take time to record the image. In addition, the scanning speed of the laser light irradiated when recording an image is usually 15000 mm / s or less, preferably 10,000 mm / s or less, and more preferably 8000 mm / s or less. If the scanning speed of the laser beam irradiated when recording an image exceeds 15000 mm / s, it may be difficult to form an image uniformly.

  The spot diameter of the laser beam irradiated when recording an image is usually 0.02 mm or more, preferably 0.1 mm or more, and more preferably 0.15 mm or more. When the spot diameter of the laser beam irradiated when recording an image is less than 0.02 mm, the line width of the image becomes narrow and visibility may be lowered. Further, the spot diameter of the laser beam irradiated when recording an image is usually 3.0 mm or less, preferably 2.5 mm or less, and more preferably 2.0 mm or less. If the spot diameter of the laser beam irradiated when recording an image exceeds 3.0 mm, the line width of the image becomes thick, and adjacent lines may overlap, making it difficult to record a small image.

The light source of the laser light is not particularly limited, and examples thereof include a semiconductor laser, a YAG laser, a fiber laser, and a CO ₂ laser. Among these, a semiconductor laser is preferable because it has a wide wavelength selectivity, a small light source, and a reduction in size and cost of the apparatus.

  The wavelength of laser light emitted from a semiconductor laser, YAG laser, or fiber laser is usually 700 nm or more, preferably 720 nm or more, and more preferably 750 nm or more. When recording an image, if the wavelength of laser light emitted from a semiconductor laser, YAG laser, or fiber laser is in the visible light region of less than 700 nm, the contrast of the image recorded on the thermoreversible recording medium is reduced, The thermoreversible recording medium may be colored. When the wavelength of laser light emitted from a semiconductor laser, YAG laser, or fiber laser is in the ultraviolet region, the thermoreversible recording medium may be easily deteriorated. In addition, the photothermal conversion material added to the thermoreversible recording medium requires a high decomposition temperature in order to ensure durability. When an organic dye is used as the photothermal conversion material, the photothermal conversion material has a high decomposition temperature and a long absorption wavelength. Hard to get. For this reason, the wavelength of the laser light emitted from the semiconductor laser, YAG laser, or fiber laser is usually 2000 nm or less, preferably 1500 mm or less, and more preferably 1200 nm or less.

The wavelength of the laser light emitted from the CO ₂ laser is 10.6 μm in the far infrared region, and even on the surface of the thermoreversible recording medium without adding an additive for absorbing the laser light and generating heat. Absorbs laser light. In addition, even if a laser beam having a wavelength in the near-infrared region is used as an additive, visible light may also be absorbed, but a CO ₂ laser that does not require an additive is used for thermoreversible recording. A decrease in contrast of an image recorded on a medium can be suppressed.

  FIG. 4 shows an example of the image processing apparatus.

  The image processing apparatus has an oscillator unit including a laser oscillator 1, a beam expander 2, and a scanning unit 5.

  The laser oscillator 1 arranges mirrors on both sides of the laser medium, pumps the laser medium, increases the number of excited atoms, forms an inversion distribution, and stimulates emission. As a result, only the light in the optical axis direction is selectively amplified, so that the directivity of the light is increased and the laser light is emitted from the output mirror.

  The scanning unit 5 includes a galvanometer 4 and a mirror 4A attached to the galvanometer 4. The laser light output from the laser oscillator 1 is rotated and scanned by two mirrors 4A in the X-axis direction and the Y-axis direction attached to the galvanometer 4, thereby recording an image on the thermoreversible recording medium 100. Or erase.

  The image processing apparatus includes a power source control unit that includes a drive power source for a light source that excites a laser medium, a drive power source for a galvanometer, a cooling power source for a Peltier element, and a control unit that controls each unit.

  The image processing apparatus has a program unit for inputting and creating an image by inputting conditions such as laser light intensity and laser scanning speed in order to record or erase an image by touch panel input or keyboard input.

  The image processing apparatus further includes a transport unit that transports the thermoreversible recording medium 100, a touch panel, and the like.

  The thermoreversible recording medium 100 has a thermoreversible recording layer formed on a support, and if necessary, a photothermal conversion layer, an oxygen blocking layer, an ultraviolet absorbing layer, an intermediate layer, a protective layer, an under layer, a back layer. Further, an adhesive layer, an adhesive layer, a colored layer, an air layer, a light reflecting layer, and the like are further formed.

  Each of these layers may have a single layer structure or a laminated structure.

  In addition, when a photothermal conversion material is added, it is added to the thermoreversible recording layer or the photothermal conversion layer, but it is preferably added to the thermoreversible recording layer from the viewpoint of recording sensitivity.

  Photothermal conversion materials can be broadly classified into inorganic materials and organic materials.

  The inorganic material is not particularly limited, and examples thereof include metals or metalloids such as carbon black, Ge, Bi, In, Te, Se, and Cr, alloys containing metal or metalloid, metal borides, and metal oxides. .

  Examples of the metal boride and metal oxide include hexaboride, tungsten oxide, antimony-doped tin oxide (ATO), tin-doped indium oxide (ITO), and zinc antimonate. Among these, hexaboride and tungsten oxide are preferable because of less absorption in the visible region.

  Although it does not specifically limit as an organic material, When using a semiconductor laser as a light source, the near-infrared absorption pigment | dye which has an absorption peak in a 700-1500 nm wavelength range is used.

  Examples of near infrared absorbing dyes include cyanine dyes, quinone dyes, quinoline derivatives of indonaphthol, phenylenediamine nickel complexes, phthalocyanine compounds, and the like, and two or more of them may be used in combination. Of these, phthalocyanine compounds are preferred because of their excellent heat resistance.

  FIG. 8 shows a first example of the layer structure of the thermoreversible recording medium.

  In the thermoreversible recording medium 100 </ b> A, a thermoreversible recording layer 120 is formed on a support 110.

  FIG. 9 shows a second example of the layer structure of the thermoreversible recording medium.

  In the thermoreversible recording medium 100B, a thermoreversible recording layer 120 and a photothermal conversion layer 130 are sequentially stacked on a support 110.

  The order in which the thermoreversible recording layer 120 and the photothermal conversion layer 130 are stacked may be reversed.

  FIG. 10 shows a third example of the layer structure of the thermoreversible recording medium.

  In the thermoreversible recording medium 100C, a thermoreversible recording layer 120A, a photothermal conversion layer 130, and a thermoreversible recording layer 120B are sequentially laminated on a support 110.

  Although it does not specifically limit as a shape of the support body 110, Flat shape etc. are mentioned.

  The structure of the support 110 may be a single layer structure or a laminated structure.

  The material constituting the support 110 is not particularly limited, but inorganic materials such as glass, quartz, silicon, silicon oxide, aluminum oxide, metal, paper, cellulose derivatives such as cellulose triacetate, synthetic paper, polyethylene terephthalate, polycarbonate Organic materials such as polystyrene and polymethyl methacrylate may be used, and two or more kinds may be used in combination. Among these, organic materials are preferable, polyethylene terephthalate, polycarbonate, and polymethyl methacrylate are more preferable, and polyethylene terephthalate is particularly preferable.

  The support 110 is preferably surface-modified. Thereby, the adhesiveness of a coating layer can be improved.

  The surface modification treatment is not particularly limited, and examples thereof include corona discharge treatment, oxidation reaction treatment (for example, chromic acid treatment), etching treatment, easy adhesion treatment, and antistatic treatment.

  The support 110 preferably contains a white pigment such as titanium oxide.

  The average thickness of the support 110 is usually 10 μm to 2 mm, and preferably 20 μm to 1 mm.

  Note that the support 110 may be omitted.

  The thermoreversible recording layer 120 includes a material in which either transparency or color tone reversibly changes depending on temperature.

  A material whose transparency and color tone reversibly change depending on the temperature is a material that can exhibit a phenomenon that causes a visible change reversibly due to temperature change. Depending on the difference in cooling rate, it is possible to change between a relatively colored state and a decolored state. In this case, the visible change is divided into a color state change and a shape change. The change in the color state is caused by, for example, changes in transmittance, reflectance, absorption wavelength, scattering degree, etc., and the color state of the thermoreversible recording medium actually changes depending on a combination of these changes.

  The material in which either the transparency or the color tone reversibly changes depending on the temperature is not particularly limited. However, the material becomes transparent at the first specific temperature and becomes cloudy at the second specific temperature (Japanese Patent Application Laid-Open Sho 55-154198), materials that develop color at the second specific temperature and erase at the first specific temperature (Japanese Patent Laid-Open Nos. 4-224996, 4-247985, and 4-267190) No., etc.), a material that becomes cloudy at the first specific temperature and becomes transparent at the second specific temperature (see JP-A-3-169590), black, red, blue, etc. at the first specific temperature And a material that can be erased at a second specific temperature (see JP-A-2-188293, JP-A-2-188294, etc.). Among them, it is preferable to use a leuco dye and a developer from the viewpoint of reversibly showing a transparent state and a colored state and recording an image having a high contrast.

  A leuco dye is a colorless or light-colored dye precursor.

  The leuco dye is not particularly limited, but is triphenylmethanephthalide, triallylmethane, fluoran, phenothiazine, thioferolane, xanthene, indophthalyl, spiropyran, azaphthalide, chromenopyrazole, Examples thereof include methine series, rhodamine anilinolactam series, rhodamine lactam series, quinazoline series, diazaxanthene series, and bislactone series, and two or more kinds may be used in combination. Among these, fluoran-based or phthalide-based leuco dyes are preferable in terms of excellent color development / decoloring properties, color, and storage stability.

  The developer is not particularly limited as long as it can reversibly develop and decolorize by using heat as a factor. And a compound having at least one structure (for example, a long-chain hydrocarbon group) that controls the cohesive force between phosphoric acid groups and molecules.

  The structure having a color developing ability to develop a leuco dye is preferably a phenolic hydroxyl group.

  The carbon number of the long chain hydrocarbon group is usually 8 or more and preferably 11 or more. Moreover, carbon number of a long chain hydrocarbon group is 40 or less normally, and it is preferable that it is 30 or less.

  In addition, the structure having a color developing ability for causing the leuco dye to develop and the structure for controlling the cohesive force between molecules may be linked via a divalent or higher valent linking group containing a hetero atom. Further, the long chain hydrocarbon group may be substituted with the same linking group and / or aromatic group.

  Developer is a general formula

（式中、Ｒ^１は、単結合又は炭素数が１〜２４の２価の脂肪族炭化水素基であり、Ｒ^２は、置換基を有していてもよい炭素数が２以上の２価の脂肪族炭化水素基であり、Ｒ^３は、炭素数が１〜３５の１価の脂肪族炭化水素基であり、Ｘ及びＹは、それぞれ独立に、Ｎ原子又はＯ原子を含む２価の基であり、ｎは０又は１である。）
で表される化合物であることが好ましく、一般式

(In the formula, R ¹ is a single bond or a divalent aliphatic hydrocarbon group having 1 to 24 carbon atoms, and R ² is a divalent having 2 or more carbon atoms which may have a substituent. R ³ is a monovalent aliphatic hydrocarbon group having 1 to 35 carbon atoms, and X and Y are each independently a divalent aliphatic group containing an N atom or an O atom. And n is 0 or 1.)
Is preferably a compound represented by the general formula

で表される化合物であることがさらに好ましい。

It is further more preferable that it is a compound represented by these.

R ² preferably has 5 or more carbon atoms, more preferably 10 or more.

R ³ preferably has 6 or more carbon atoms, more preferably 8 or more.

The sum of the carbon number of R ¹ , R ² and R ³ is usually 8 or more and preferably 11 or more. Moreover, the sum of the carbon numbers of R ¹ , R ² and R ³ is usually 40 or less, and preferably 35 or less. When the sum of the carbon numbers of R ¹ , R ² and R ³ is less than 8, the color development stability and decoloring property may be lowered.

  The aliphatic hydrocarbon group may be linear or branched, and may have an unsaturated bond, but is preferably linear.

  Although it does not specifically limit as a substituent, A hydroxyl group, a halogen atom, an alkoxy group, etc. are mentioned.

Although it does not specifically limit as bivalent group containing N atom or O atom, An oxygen atom, an amide bond (-NHCO-), a urea bond (-HNCONH-), Chemical formula -COHN-NHCO-
A group represented by the formula: -HNCO-CONH-
A group represented by the formula: -HNCONHCO-
The group etc. which are represented by these are mentioned. Of these, an amide bond and a urea bond are preferable.

  The developer is dispersed in the form of particles in the thermoreversible recording layer 120.

  The thermoreversible recording layer 120 preferably further contains a decolorization accelerator.

As the decoloring accelerator, amide bond (—NHCO—) and / or chemical formula —OCONH—
If it has one or more groups represented by, it will not specifically limit.

  In the process of forming a decolored state, the decoloring accelerator induces an intermolecular interaction with the developer, and can improve the color development / decoloring characteristics.

  The thermoreversible recording layer 120 may further contain an additive in order to improve the coating characteristics and the color-decoloring characteristics.

  Although it does not specifically limit as an additive, Surfactant, a electrically conductive agent, a filler, antioxidant, a light stabilizer, a coloring stabilizer, etc. are mentioned.

  The thermoreversible recording layer 120 may further contain a binder resin.

  The binder resin is not particularly limited, but is preferably a thermoplastic resin, a thermosetting resin, an ultraviolet curable resin, or an electron beam curable resin that can be cured by a crosslinking agent in order to improve durability during repetition. A thermoplastic resin that can be cured by a crosslinking agent is particularly preferred.

  The thermoplastic resin that can be cured by the crosslinking agent is not particularly limited, but is not particularly limited as long as it has a group capable of reacting with the crosslinking agent, but is not limited thereto. Examples include propionate, cellulose acetate butyrate, acrylic polyol, polyester polyol, and polyurethane polyol. Among these, acrylic polyol, polyester polyol, and polyurethane polyol are preferable.

  The mass ratio of the binder resin to the leuco dye is usually 0.1 to 10. When the mass ratio of the binder resin to the leuco dye is less than 0.1, the thermal strength of the thermoreversible recording layer 120 may be reduced, and when it exceeds 10, the color density may be reduced.

  Although it does not specifically limit as a crosslinking agent, Isocyanates, amino resin, a phenol resin, amines, an epoxy compound, etc. are mentioned. However, isocyanates are preferred, and polyisocyanates having a plurality of isocyanate groups are particularly preferred.

  The molar ratio of the active group of the crosslinking agent to the group capable of reacting with the crosslinking agent of the thermoplastic resin is usually 0.01-2. When the molar ratio of the active group possessed by the crosslinking agent to the group capable of reacting with the crosslinking agent possessed by the thermoplastic resin is less than 0.01, the thermal strength of the thermoreversible recording layer 120 may be lowered. If it exceeds, the color development and decoloring characteristics may deteriorate.

  The crosslinking agent may be used in combination with a catalyst for the crosslinking reaction.

  The gel fraction of the thermoreversible recording layer 120 is usually 30% or more, preferably 50% or more, and more preferably 70% or more. When the gel fraction of the thermoreversible recording layer 120 is less than 30%, the durability of the thermoreversible recording medium 100 may decrease.

  A method for forming the thermoreversible recording layer 120 is not particularly limited, but after applying a coating solution in which a composition containing a binder resin, a leuco dye and a developer is dissolved or dispersed in a solvent on a support. And a drying method.

  Although it does not specifically limit as a solvent, Tetrahydrofuran, methyl ethyl ketone, methyl isobutyl ketone, chloroform, carbon tetrachloride, ethanol, toluene, benzene etc. are mentioned.

  The method for preparing the coating solution is not particularly limited, and examples thereof include a method for dissolving or dispersing the composition in a solvent, a method for dissolving or dispersing a material other than the binder resin after dissolving the binder resin in the solvent, and the like. It is done.

  The coating solution may further contain an antifoaming agent, slip agent, preservative, crosslinking agent, plasticizer and the like.

  The application method of the coating liquid is not particularly limited, but blade coating method, wire bar coating method, spray coating method, air knife coating method, bead coating method, curtain coating method, gravure coating method, kiss coating method, reverse roll coating method , Dip coating method, die coating method and the like.

  The average thickness of the thermoreversible recording layer 120 is usually 1 to 20 μm, and preferably 3 to 18 μm. If the average thickness of the thermoreversible recording layer is less than 1 μm, the color density may decrease, and if it exceeds 20 μm, the color development temperature may not be reached and a portion that does not develop color may occur.

  The photothermal conversion layer 130 includes a photothermal conversion material and is formed on one side or both sides of the thermoreversible recording layer 120.

The content of the photothermal conversion material in the light-to-heat conversion layer 130 is usually 0.005~20g / ^{m 2,} is preferably 0.01 to 10 g / ^{m 2.}

  The photothermal conversion layer 130 may further contain a binder resin.

  As the binder resin, either a thermoplastic resin or a thermosetting resin may be used, and the same resin as the binder resin of the thermoreversible recording layer 120 can be used. Among these, in order to improve durability, a thermosetting resin, an ultraviolet curable resin, and an electron beam curable resin are preferable, and a thermosetting resin that can be cured by a crosslinking agent is preferable.

  The average thickness of the photothermal conversion layer 130 is usually 0.1 to 20 μm.

  A barrier layer may be formed between the thermoreversible recording layer 120 and the photothermal conversion layer 130.

  The barrier layer includes a binder resin.

  The binder resin is not particularly limited, and examples thereof include a thermosetting resin, an ultraviolet curable resin, and an electron beam curable resin.

  An oxygen blocking layer may be further formed on the thermoreversible recording layer 120 or the photothermal conversion layer 130. Thus, by preventing oxygen from entering the thermoreversible recording layer 120 and the photothermal conversion layer 130, it is possible to prevent photodegradation of the leuco dye in the thermoreversible recording layer 120 and to repeatedly heat to a high temperature. Oxidation of the photothermal conversion material due to this can be prevented.

The oxygen permeability of the oxygen barrier layer at 25 ° C. and 80% RH is usually 0.5 mL / (m ² · 24 hr · atm) or less and 0.1 mL / (m ² · 24 hr · atm) or less. Is more preferable, and 0.05 mL / (m ² · 24 hr · atm) or less is more preferable. If the oxygen permeability of the oxygen blocking layer at 25 ° C. and 80% RH exceeds 0.5 mL / (m ² · 24 hr · atm), oxygen may not be sufficiently blocked.

  The oxygen permeability can be measured by a measuring method according to JIS K7126B method (isobaric method) and ATSMD3985.

  Although it does not specifically limit as an oxygen barrier layer, Water-soluble resin films, such as polyvinyl alcohol and an ethylene-polyvinyl alcohol copolymer, Deposition layers of inorganic oxides, such as a silica and an alumina, Resins, such as polyethylene terephthalate (PET) and nylon Examples thereof include an inorganic vapor deposition film in which a vapor deposition layer of an inorganic oxide such as silica, alumina, silica / alumina, etc. is formed on the film. Among these, an inorganic vapor deposition film is preferable. The inorganic oxide in the inorganic vapor-deposited film is preferably silica because it is inexpensive, has high oxygen barrier properties, and has little influence on temperature and humidity. Moreover, it is preferable that the resin film in an inorganic vapor deposition film is a polyethylene terephthalate (PET) from the point of vapor deposition suitability, oxygen barrier stability, and heat resistance.

  Between the thermoreversible recording layer 120 or the photothermal conversion layer 130 and the oxygen blocking layer, an ultraviolet absorbing layer, an intermediate layer, a protective layer, an adhesive layer, an adhesive layer, and the like may be further formed.

  An oxygen blocking layer is further formed between the support 110 and the thermoreversible recording layer 120 or the photothermal conversion layer 130 or on the surface of the support 110 where the thermoreversible recording layer 120 is not formed. Is preferred. Thereby, oxygen can be cut off effectively.

  Note that the oxygen blocking layers formed above and below the thermoreversible recording layer 120 may be the same or different.

  The method for forming the (water-soluble) resin film is not particularly limited, and examples thereof include a coating method and a laminating method.

  The method for depositing the inorganic oxide is not particularly limited, and examples thereof include a PVD method and a CVD method.

  The average thickness of the oxygen blocking layer is usually 0.005 to 1000 μm, preferably 0.007 to 500 μm. When the average thickness of the oxygen blocking layer exceeds 1000 μm, the transparency may be lowered and the recording sensitivity may be lowered.

  The average thickness of the vapor deposition layer of an inorganic oxide is 5-100 nm normally, and it is preferable that it is 7-80 nm. If the average thickness of the inorganic oxide vapor deposition layer is less than 5 nm, oxygen may be insufficiently blocked. If the average thickness exceeds 100 nm, transparency may be lowered or coloring may occur.

  An adhesive layer or an adhesive layer may be further formed between the oxygen blocking layer and the lower layer.

  Although it does not specifically limit as a formation method of an contact bonding layer or an adhesion layer, A coating method, a lamination method, etc. are mentioned.

  The average thickness of the adhesive layer or the pressure-sensitive adhesive layer is usually 0.1 to 20 μm.

  The material constituting the adhesive layer or the adhesive layer is not particularly limited, but urea resin, melamine resin, phenol resin, epoxy resin, vinyl acetate resin, vinyl acetate-acrylic copolymer, ethylene-vinyl acetate copolymer , Acrylic resin, polyvinyl ether resin, vinyl chloride-vinyl acetate copolymer, polystyrene resin, polyester resin, polyurethane resin, polyamide resin, chlorinated polyolefin resin, polyvinyl butyral resin, acrylic ester Examples thereof include a copolymer, a methacrylate ester copolymer, natural rubber, a cyanoacrylate resin, and a silicone resin.

  The adhesive layer or the pressure-sensitive adhesive layer may be cross-linked by a cross-linking agent or may be a hot melt type.

  Two or more inorganic vapor deposition films may be laminated. Thereby, oxygen barrier property can be improved.

  Although it does not specifically limit as a method of laminating | stacking an inorganic vapor deposition film, The method etc. which are bonded together using an contact bonding layer or an adhesion layer are mentioned.

  A protective layer may be further formed on the thermoreversible recording layer 120 or the photothermal conversion layer 130.

  The protective layer is preferably formed on the surface.

  The protective layer contains a binder resin and may further contain a release agent, a filler, and the like.

  The binder resin is not particularly limited, and examples thereof include a thermosetting resin, an ultraviolet curable resin, and an electron beam curable resin. Among these, an ultraviolet curable resin and a thermosetting resin are preferable.

  Use of UV curable resin can form a hard protective layer, and can prevent damage due to physical contact with the surface and deformation of the thermoreversible recording medium due to laser heating, thus improving durability. Can do.

  Further, when a thermosetting resin is used, the durability can be improved although it is slightly inferior to the case of using an ultraviolet curable resin.

  The UV curable resin is not particularly limited, but urethane acrylate, epoxy acrylate, polyester acrylate, polyether acrylate, vinyl, unsaturated polyester oligomer, monofunctional or polyfunctional acrylate, monofunctional or Monomers such as polyfunctional methacrylates, vinyl esters, ethylene derivatives, and allyl compounds are listed. Of these, tetrafunctional or higher polyfunctional monomers or oligomers are preferable.

  At this time, the hardness, shrinkage, flexibility, and coating strength of the protective layer can be adjusted by using two or more ultraviolet curable resins in combination.

  In order to cure the ultraviolet curable resin, it is necessary to use a photopolymerization initiator and a photopolymerization accelerator.

  The mass ratio of the photopolymerization initiator or photopolymerization accelerator to the ultraviolet curable resin is usually 0.1 to 20%, and preferably 1 to 10%.

  The method of curing the ultraviolet curable resin is not particularly limited, and examples thereof include a method of irradiating ultraviolet rays using an ultraviolet irradiation device.

  The ultraviolet irradiation device includes a light source, a lamp, a power source, a cooling device, a transport device, and the like.

  Although it does not specifically limit as a light source, A mercury lamp, a metal halide lamp, a potassium lamp, a mercury xenon lamp, a flash lamp etc. are mentioned.

  As the thermosetting resin, the same resin as the thermosetting resin of the thermoreversible recording layer 120 can be used.

  The thermosetting resin preferably has a group capable of reacting with a crosslinking agent such as a hydroxyl group, an amino group, or a carboxyl group, and more preferably has a hydroxyl group.

  As the crosslinking agent, the same crosslinking agent as that of the thermoreversible recording layer 120 can be used.

  Examples of the release agent include a silicone resin having a polymerizable group, a resin grafted with a silicone resin, wax, zinc stearate, and silicone oil in order to improve transportability.

  The mass ratio of the release agent to the binder resin is usually 0.01 to 50%, preferably 0.1 to 40%.

  The protective layer may further contain a surfactant, a leveling agent, an antistatic agent and the like.

  As a method for forming the protective layer, a method similar to the method for forming the thermoreversible recording layer 120 can be used.

  The average thickness of the protective layer is usually 0.1 to 20 μm, preferably 0.5 to 10 μm, and more preferably 1.5 to 6 μm. When the average thickness of the protective layer is less than 0.1 μm, the durability of the thermoreversible recording medium 100 may be reduced, and when it exceeds 20 μm, the color development / decoloration characteristics of the thermoreversible recording medium 100 may be reduced. is there.

  It is preferable that an ultraviolet absorbing layer is further formed on the thermoreversible recording layer 120 or the photothermal conversion layer 130. As a result, it is possible to prevent deterioration of the resin component in the thermoreversible recording layer 120 due to ultraviolet rays, coloring of the leuco dye due to ultraviolet rays, and disappearance due to photodegradation.

  The ultraviolet absorbing layer contains an ultraviolet absorber and may further contain a binder resin, a filler, a lubricant and the like.

  As the ultraviolet absorber, either an organic compound or an inorganic compound may be used.

  Although it does not specifically limit as an organic type ultraviolet absorber, Ultraviolet absorbers, such as a benzotriazole type, a benzophenone type, a salicylic acid ester type, a cyanoacrylate type, and a cinnamic acid type, are mentioned. Among these, benzotriazole-based ultraviolet absorbers are preferable, and ultraviolet absorbers in which hydroxyl groups are protected by adjacent bulky groups are more preferable.

  Specific examples of the benzotriazole ultraviolet absorber include 2- (2′-hydroxy-3 ′, 5′-di-t-butylphenyl) benzotriazole, 2- (2′-hydroxy-3′-t- Butyl-5′-methylphenyl) benzotriazole, 2- (2′-hydroxy-3 ′, 5′-di-t-butylphenyl) -5-chlorobenzotriazole, 2- (2′-hydroxy-3′-) t-butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-5'-t-octylphenyl) benzotriazole, 2,2'-methylenebis [6-2H-benzotriazole- 2-yl] -4- (1,1,3,3-tetramethylbutyl) phenol]) and the like.

  In addition, when used for a long period of time, an ultraviolet absorbing structure may be pendant on a copolymerized polymer such as an acrylic resin or a styrene resin to prevent aggregation or bleeding of the ultraviolet absorber. After coating the surface of an inorganic material such as an organic ultraviolet absorber, the surface may be treated with dimethicone.

  The content of the organic ultraviolet absorber in the ultraviolet absorbing layer is usually 1 to 95% by mass.

  The inorganic ultraviolet absorber is not particularly limited, but zinc oxide, indium oxide, alumina, silica, zirconia, tin oxide, cerium oxide, iron oxide, antimony oxide, barium oxide, calcium oxide, barium oxide, bismuth oxide, Metal oxides such as nickel oxide, magnesium oxide, chromium oxide, manganese oxide, tantalum oxide, niobium oxide, thorium oxide, hafnium oxide, molybdenum oxide, iron ferrite, nickel ferrite, cobalt ferrite, barium titanate, potassium titanate, etc. Composite oxides, metal sulfides or sulfate compounds such as zinc sulfide and barium sulfate, titanium carbide, silicon carbide, molybdenum carbide, tungsten carbide, tantalum carbide and other metal carbides, aluminum nitride, silicon nitride Boron nitride, zirconium nitride, vanadium nitride, titanium nitride, niobium nitride, and metal nitrides such as gallium nitride. Among these, metal oxides or composite oxides thereof are preferable, and silica, alumina, zinc oxide, titanium oxide, cerium oxide, and bismuth oxide are more preferable.

  The average particle size of the inorganic ultraviolet absorber is usually 100 nm or less.

  The surface of the inorganic ultraviolet absorber may be treated with silicone, wax, organic silane, silica or the like.

  The content of the inorganic ultraviolet absorber in the ultraviolet absorbing layer is usually 1 to 95% by volume.

  As the binder resin, either a thermoplastic resin or a thermosetting resin may be used, and the same resin as the binder resin of the thermoreversible recording layer 120 can be used.

  The binder resin is not particularly limited, and examples thereof include polyethylene, polypropylene, polystyrene, polyvinyl alcohol, polyvinyl butyral, polyurethane, saturated polyester, unsaturated polyester, epoxy resin, phenol resin, polycarbonate, and polyamide.

  The average thickness of the ultraviolet absorbing layer is usually from 0.1 to 30 μm, and preferably from 0.5 to 20 μm.

  As a method for forming the ultraviolet absorbing layer, a method similar to the method for forming the thermoreversible recording layer 120 can be used.

  Note that an ultraviolet absorber may be added to the thermoreversible recording layer 120.

  An intermediate layer may be further formed on the thermoreversible recording layer 120 or the photothermal conversion layer 130. Thereby, the adhesiveness of the thermoreversible recording layer 120 or the photothermal conversion layer 130 and the oxygen blocking layer can be improved, and the surface of the thermoreversible recording layer 120 or the photothermal conversion layer 130 can be smoothed.

  The intermediate layer includes a binder resin and may further include a filler, a lubricant, and the like.

  As the binder resin, either a thermoplastic resin or a thermosetting resin may be used, and the same resin as the binder resin of the thermoreversible recording layer can be used.

  The intermediate layer may further contain an ultraviolet absorber similar to the ultraviolet absorbing layer.

  The average thickness of the intermediate layer is usually 0.1 to 20 μm, and preferably 0.5 to 10 μm.

  As a method for forming the intermediate layer, a method similar to the method for forming the thermoreversible recording layer can be used.

  An under layer may be further formed between the thermoreversible recording layer 120 or the photothermal conversion layer 130 and the support 110. Accordingly, the heat generated is effectively utilized to increase the sensitivity, and the adhesion between the support 110 and the thermoreversible recording layer 120 or the photothermal conversion layer 130 is improved, so that the thermoreversible recording layer 120 to the support 110 is improved. Alternatively, permeation of the material of the photothermal conversion layer 130 can be prevented.

  The under layer includes hollow particles and may further include a binder resin or the like.

  Examples of the hollow particles include single hollow particles in which one hollow portion is present in the particle, multi-hollow particles in which many hollow portions are present in the particle, and the like, and two or more kinds may be used in combination.

  Although it does not specifically limit as a material which comprises a hollow particle, A thermoplastic resin etc. are mentioned.

  Examples of commercially available hollow particles include Microsphere R-300 (manufactured by Matsumoto Yushi Co., Ltd.), Ropaque HP1055, Ropaque HP433J (above, manufactured by Nippon Zeon Co., Ltd.), SX866 (manufactured by JSR Corporation), and the like.

  The content of the hollow particles in the under layer is usually 10 to 80% by mass.

  As the binder resin, either a thermoplastic resin or a thermosetting resin may be used, and the same resin as the binder resin of the thermoreversible recording layer can be used.

  The under layer may further contain a filler, a lubricant, a surfactant, a dispersant and the like.

  As the filler, either an inorganic filler or an organic filler may be used, but an inorganic filler is preferably used.

  The material constituting the inorganic filler is not particularly limited, and examples thereof include calcium carbonate, magnesium carbonate, titanium oxide, silicon oxide, aluminum hydroxide, kaolin, and talc.

  The average thickness of the under layer is usually 1 to 80 μm, preferably 4 to 70 μm, and more preferably 12 to 60 μm.

  A back layer may be further formed on the side of the support 110 where the thermoreversible recording layer 120 is not formed. As a result, curling and charging of the thermoreversible recording medium 100 can be prevented and the transportability can be improved.

  The back layer contains a binder resin and may further contain a filler, a conductive filler, a lubricant, and the like.

  The binder resin is not particularly limited, and examples thereof include a thermosetting resin, an ultraviolet curable resin, and an electron beam curable resin. Among these, an ultraviolet curable resin and a thermosetting resin are preferable. As the binder resin, a resin similar to the binder resin of the thermoreversible recording layer 120 can be used.

  An adhesive layer or an adhesive layer may be further formed on the side of the support 110 where the thermoreversible recording layer 120 is not formed to form a thermoreversible recording label. Thereby, a thermoreversible recording label can be affixed on the entire surface or a part of a thick substrate such as a PVC card with a magnetic stripe that is difficult to form by applying the thermoreversible recording layer 120. As a result, a part of the information stored in the magnetism can be displayed, and convenience is improved. The thermoreversible recording label can also be applied to thick cards such as IC cards and optical cards.

  The material constituting the adhesive layer or the adhesive layer is not particularly limited, but urea resin, melamine resin, phenol resin, epoxy resin, vinyl acetate resin, vinyl acetate-acrylic copolymer, ethylene-vinyl acetate copolymer , Acrylic resin, polyvinyl ether resin, vinyl chloride-vinyl acetate copolymer, polystyrene resin, polyester resin, polyurethane resin, polyamide resin, chlorinated polyolefin resin, polyvinyl butyral resin, acrylic ester Examples thereof include a copolymer, a methacrylate ester copolymer, natural rubber, a cyanoacrylate resin, and a silicone resin.

  The adhesive layer or the pressure-sensitive adhesive layer may be crosslinked with a crosslinking agent or may be a hot melt type.

  The thermoreversible recording label may be a release paper type in which a release paper is attached on an adhesive layer or an adhesive layer, or may be a non-release paper type in which no release paper is attached on an adhesive layer or an adhesive layer. .

  A colored layer may be further formed between the support 110 and the thermoreversible recording layer 120. Thereby, visibility can be improved.

  The colored layer includes a colorant and a binder resin.

  Although it does not specifically limit as a formation method of a colored layer, The method of drying after apply | coating the coating liquid in which the composition containing a coloring agent and binder resin is melt | dissolving or disperse | distributing in a solvent, A coloring agent and binder resin are included. The method etc. which stick a colored sheet are mentioned.

  The thermoreversible recording medium 100 may further include a thermally irreversible recording layer. In this case, the color tone of the thermoreversible recording layer may be the same as or different from the color tone of the thermoreversible recording layer 120.

  Offset printing or gravure printing on a part or the entire surface of the thermoreversible recording medium 100 where the thermoreversible recording layer 120 is formed or a part of the thermoreversible recording medium 100 where the thermoreversible recording layer 120 is not formed. A pattern or the like may be further formed by printing such as an ink jet printer, a thermal transfer printer, a sublimation printer, or the like. At this time, an OP varnish layer containing a curable resin may be further formed on a part or the entire surface of the pattern.

  In addition, you may color by adding dye and / or a pigment to either of each layer.

  The thermoreversible recording medium 100 may be provided with a hologram in order to improve security. Further, the thermoreversible recording medium 100 may be provided with a design such as a person image, a company emblem, a symbol mark, or the like by forming irregularities in a relief shape or an intaglio shape in order to impart design properties.

  The shape of the thermoreversible recording medium 100 is not particularly limited, and examples thereof include a card shape, a tag shape, a label shape, a sheet shape, and a roll shape.

  Examples of the card-like thermoreversible recording medium 100 include prepaid cards, point cards, credit cards, and the like.

  Examples of the tag-like thermoreversible recording medium 100 smaller than the card size include a price tag. On the other hand, the tag-like thermoreversible recording medium 100 larger than the card size includes a process management document, a shipping instruction document, a ticket, and the like.

  The label-like thermoreversible recording medium 100 is processed into various sizes and then attached to a cart, a container, a box, a container, etc., and can be used for process management, article management, and the like.

  Examples of the sheet-like thermoreversible recording medium 100 include general documents and process management instructions.

  The image processing method and image processing apparatus can be applied to logistics and delivery systems because it can record and erase images repeatedly at high speed on thermoreversible recording media such as labels attached to containers such as cardboard and plastic containers. can do. In this case, for example, an image can be recorded and erased on the label while moving the cardboard or the plastic container placed on the belt conveyor, and the shipping time can be shortened because the line does not need to be stopped. Also, the cardboard or plastic container with the label attached can be reused as it is without peeling off the label, and the image can be erased and recorded again.

  Examples of the present invention will be described below, but the present invention is not limited to the examples. In addition, a part means a mass part.

(Preparation of thermoreversible recording medium 1)
A white polyester film Tetron (registered trademark) film U2L98W (manufactured by Teijin DuPont) having an average thickness of 125 μm was used as a support.

  30 parts of a styrene-butadiene copolymer PA-9159 (manufactured by Nippon A & L), 12 parts of polyvinyl alcohol POVAL PVA103 (manufactured by Kuraray), 20 parts of hollow particle microsphere R-300 (manufactured by Matsumoto Yushi Co., Ltd.) and water 40 parts was stirred for 1 hour, and the coating liquid for underlayers was obtained.

  An under layer coating solution was applied onto the support using a wire bar, and then dried at 80 ° C. for 2 minutes to form an under layer having an average thickness of 20 μm.

  Chemical formula

で表される顕色剤５部、化学式

5 parts developer represented by the chemical formula

で表される消色促進剤１部、水酸基価が２００ｍｇＫＯＨ／ｇのアクリルポリオールの５０質量％溶液１０部及びメチルエチルケトン８０部を、ボールミルを用いて平均粒径が約１μｍになるまで分散させた。次に、ロイコ染料２−アニリノ−３−メチル−６−ジエチルアミノフルオラン１部、光熱変換材料ＬａＢ_６の１．８５質量％分散液ＫＨＦ−７Ａ（住友金属鉱山社製）１．２部及びイソシアネートのコロネートＨＬ（日本ポリウレタン社製）５部を加えた後、撹拌して、熱可逆記録層用塗布液を得た。

1 part, 10 parts of a 50% by weight acrylic polyol solution having a hydroxyl value of 200 mgKOH / g, and 80 parts of methyl ethyl ketone were dispersed using a ball mill until the average particle size was about 1 μm. Next, 1 part of leuco dye 2-anilino-3-methyl-6-diethylaminofluorane, 1.2 part of 1.85% by weight dispersion KHF-7A (manufactured by Sumitomo Metal Mining) of photothermal conversion material LaB ₆ and isocyanate After adding 5 parts of Coronate HL (manufactured by Nippon Polyurethane Co., Ltd.), the mixture was stirred to obtain a coating solution for a thermoreversible recording layer.

  After applying the thermoreversible recording layer coating solution on the under layer using a wire bar, the thermoreversible recording layer having an average thickness of 10 μm is dried at 100 ° C. for 2 minutes and cured at 60 ° C. for 24 hours. Formed.

  A UV absorbent polymer coating solution was obtained by stirring 10 parts UV-G302 (manufactured by Nippon Shokubai Co., Ltd.) 10 parts, 1 part of an isocyanate coronate HL (manufactured by Nippon Polyurethane) and 12 parts of methyl ethyl ketone. .

  On the thermoreversible recording layer, an ultraviolet absorbing layer coating solution is applied using a wire bar, then dried at 90 ° C. for 1 minute, and crosslinked at 60 ° C. for 24 hours to form an ultraviolet absorbing layer having an average thickness of 10 μm. Formed.

Urethane adhesive TM-567 (manufactured by Toyo Morton Co., Ltd.), 5 parts, isocyanate CAT-RT-37 (manufactured by Toyo Morton Co., Ltd.) and 5 parts of ethyl acetate were stirred to obtain an adhesive layer coating solution. . Next, after applying the adhesive layer coating liquid using a wire bar on a silica-deposited PET film IB-PET-C (Dai Nippon Printing Co., Ltd.) having an oxygen permeability of 15 mL / m ² / day / MPa, It was dried at 80 ° C. for 1 minute to form an adhesive layer. Further, the silica-deposited PET film on which the adhesive layer was formed was bonded onto the ultraviolet absorbing layer, and then heated at 50 ° C. for 24 hours to form a first oxygen blocking layer having an average thickness of 12 μm.

  An average thickness of 12 μm is obtained in the same manner as in the first oxygen blocking layer except that the silica-deposited PET film with the adhesive layer formed thereon is bonded to the surface of the support on which the thermoreversible recording layer is not formed. A second oxygen barrier layer was formed.

  Pentaerythritol hexaacrylate KAYARAD DPHA (Nippon Kayaku Co., Ltd.) 3 parts, urethane acrylate oligomer art resin UN-3320HA (Negami Kogyo Co., Ltd.) 3 parts, dipentaerythritol caprolactone acrylate ester KAYARAD DPCA-120 (Japan) 3 parts of Kayaku Co., Ltd., 1 part of silica P-526 (manufactured by Mizusawa Chemical Co., Ltd.), 0.5 part of photopolymerization initiator Irgacure 184 (manufactured by Ciba Geigy Japan) and 11 parts of isopropyl alcohol were averaged using a ball mill. Dispersion was carried out until the particle size became about 3 μm to obtain a coating solution for protective layer.

  On the first oxygen barrier layer, a protective layer coating solution is applied using a wire bar, dried at 90 ° C. for 1 minute, and irradiated with ultraviolet rays using an 80 W / cm ultraviolet lamp to be crosslinked. A protective layer having an average thickness of 4 μm was formed.

  Pentaerythritol hexaacrylate KAYARAD DPHA (manufactured by Nippon Kayaku Co., Ltd.) 7.5 parts, urethane acrylate oligomer art resin UN-3320HA (manufactured by Negami Kogyo Co., Ltd.) 2.5 parts, photopolymerization initiator Irgacure 184 (manufactured by Ciba Geigy Japan) 0.5 parts and 13 parts of isopropyl alcohol were stirred using a ball mill to obtain a coating solution for a back layer.

  On the first oxygen barrier layer, a back layer coating solution was applied using a wire bar, dried at 90 ° C. for 1 minute, and crosslinked by irradiation with an 80 W / cm ultraviolet lamp, and an average thickness of 4 μm. The back layer was formed.

  The thermoreversible recording medium 1 was obtained by cutting into a size of 45 mm length and 55 mm width.

(Preparation of thermoreversible recording medium 2)
A thermoreversible recording layer coating solution is obtained in the same manner as the thermoreversible recording medium 1 except that the 1.85% by mass dispersion KHF-7A (manufactured by Sumitomo Metal Mining Co., Ltd.) of the photothermal conversion material LaB ₆ is not added. It was.

6 parts of 50% by weight acrylic polyol resin solution LR327 (manufactured by Mitsubishi Rayon), 1.25 parts of 1.85% by weight dispersion KHF-7A (manufactured by Sumitomo Metal Mining) of photothermal conversion material LaB ₆ , coronate HL of isocyanate 2.4 parts (made by Nippon Polyurethane Co., Ltd.) and 14 parts of methyl ethyl ketone were stirred to obtain a coating solution for a photothermal conversion layer.

  Except for using the obtained thermoreversible recording layer coating liquid and applying the photothermal conversion layer coating liquid on the thermoreversible recording layer to further form a photothermal conversion layer, the same procedure as in the thermoreversible recording medium 1 was performed. A thermoreversible recording medium 2 was obtained.

  At this time, a photothermal conversion layer coating solution was applied on the thermoreversible recording layer using a wire bar, dried at 90 ° C. for 1 minute, and crosslinked at 60 ° C. for 2 hours to obtain a photothermal material having an average thickness of 3 μm. A conversion layer was formed.

(Example 1-1)
Using a semiconductor laser marker LDM200 series (manufactured by Ricoh Co., Ltd.), the thermoreversible recording medium 1 is 2.5 mm above and below, left and right under the conditions of an output of 18 W, an irradiation distance of 150 mm, a spot diameter of 0.5 mm, and a scanning speed of 3000 mm / s. A blank image was provided, and a solid image was recorded by irradiating an image recording area of 40 mm × 50 mm with laser light having a center wavelength of 980 nm.

  Next, under the conditions of an output of 24 W, an irradiation distance of 190 mm, a spot diameter of 3.0 mm, and a scanning speed of 1900 mm / s, the solid image is erased by scanning the thermoreversible recording medium 1 on which the solid image is recorded in parallel. did. Specifically, the direction in which the laser beam is scanned is the short direction of the image recording region 101, and the image recording region 101 in which the laser beam is scanned in parallel is equally divided into two laser beam scanning directions. The image was erased by dividing into regions 101a and 101b (see FIG. 5). At this time, the length of the drawing line of the laser beam was 20.3 mm, that is, the overlapping width L of the adjacent regions 101a and 101b was 0.6 mm. Further, the laser beam irradiation interval was set to 0.2 to 0.4 mm, and the scanning directions of the adjacent laser beams were the same. As a result, the laser beam irradiation interval when the remaining amount of the solid image was 0.03 was 0.25 mm, and the time for erasing the solid image was 5.3 seconds. At this time, the solid image at the boundary between adjacent regions was sufficiently erased.

(Remaining amount of solid image)
First, the background density of the image recording area before forming the solid image and the density of the image recording area after erasing the solid image were measured using X-Rite 939 (manufactured by X-Rite), and the equation (solid image) Density of image recording area after erasing)-(background density of image recording area)
Thus, the remaining amount of the solid image was obtained.

(Example 1-2)
A solid image was recorded and erased in the same manner as in Example 1-1 except that the image recording area 101 scanned in parallel with laser light was divided into four areas 101a, 101b, 101c, and 101d (FIG. 3). At this time, the length of the drawing line of the laser beam was 10.45 mm, that is, the overlapping width L of the adjacent regions 101a and 101b, 101b and 101c, 101c and 101d was 0.6 mm. As a result, the laser beam irradiation interval when the remaining amount of the solid image was 0.03 was 0.30 mm, and the time for erasing the solid image was 4.8 seconds. At this time, the solid image at the boundary between adjacent regions was sufficiently erased.

(Example 1-3)
A solid image was recorded and erased in the same manner as in Example 1-2 except that the overlapping width L of the adjacent regions 101a and 101b, 101b and 101c, 101c and 101d was 1.2 mm. At this time, the length of the drawing line of the laser beam was 10.9 mm. As a result, the laser beam irradiation interval when the remaining amount of the solid image was 0.03 was 0.30 mm, and the time for erasing the solid image was 5.2 seconds. At this time, the solid image at the boundary between adjacent regions was sufficiently erased.

(Example 1-4)
A solid image was recorded and erased in the same manner as in Example 1-2 except that the overlapping width L of the adjacent regions 101a and 101b, 101b and 101c, 101c and 101d was 4.2 mm. At this time, the length of the drawing line of the laser beam was 13.15 mm. As a result, the laser beam irradiation interval when the remaining amount of the solid image was 0.03 was 0.28 mm, and the time for erasing the solid image was 6.3 seconds. At this time, the solid image at the boundary between adjacent regions was sufficiently erased.

(Example 1-5)
A solid image was recorded and erased in the same manner as in Example 1-2 except that the overlapping width L of the adjacent regions 101a and 101b, 101b and 101c, 101c and 101d was 4.8 mm. At this time, the length of the drawing line of the laser beam was 13.60 mm. As a result, the laser beam irradiation interval when the remaining amount of the solid image was 0.03 was 0.28 mm, and the time for erasing the solid image was 6.6 seconds. At this time, the solid image at the boundary between adjacent regions was sufficiently erased.

(Example 1-6)
Except for the overlap width L of the adjacent regions 101a and 101b, 101b and 101c, 101c and 101d being 0.8 mm, the laser beam scanning speed of 1500 to 3000 mm / s, and the laser beam irradiation interval of 0.20 mm. In the same manner as in Example 1-2, a solid image was recorded and then erased. At this time, the length of the drawing line of the laser beam was 10.6 mm. As a result, the scanning speed of the laser beam when the remaining amount of the solid image was 0.03 was 2780 mm / s, and the time for erasing the solid image was 5.8 seconds. At this time, the solid image at the boundary between adjacent regions was sufficiently erased.

(Example 1-7)
After recording the solid image in the same manner as in Example 1-1, except that the image recording area 101 that scans the laser beams in parallel is divided into six areas 101a, 101b, 101c, 101d, 101e, and 101f, Erased (see FIG. 6). At this time, the length of the drawing line of the laser beam is 7.17 mm, that is, the overlapping width L of the adjacent regions 101a and 101b, 101b and 101c, 101c and 101d, 101d and 101e, 101e and 101f is 0.6 mm. . As a result, the laser beam irradiation interval when the remaining amount of the solid image was 0.03 was 0.33 mm, and the time for erasing the solid image was 4.7 seconds. At this time, the solid image at the boundary between adjacent regions was sufficiently erased.

(Comparative Example 1-1)
A solid image was recorded and then erased (see FIG. 4) in the same manner as in Example 1-1 except that the image recording area 101 scanned in parallel with laser light was not divided. At this time, the length of the drawing line of the laser beam was 40 mm. As a result, the laser beam irradiation interval when the remaining amount of the solid image was 0.03 was 0.19 mm, and the time for erasing the solid image was 6.7 seconds.

(Comparative Example 1-2)
A solid image was recorded and then erased in the same manner as in Example 1-2 except that the overlapping width L of the adjacent regions 101a and 101b, 101b and 101c, 101c and 101d was 0 mm. At this time, the length of the laser light drawing line was set to 10 mm. As a result, the time for erasing the solid image was 4.7 seconds, but the solid image at the boundary between adjacent regions was not sufficiently erased.

(Comparative Example 1-3)
A solid image was recorded and then erased in the same manner as in Example 1-2 except that the overlapping width L of the adjacent regions 101a and 101b, 101b and 101c, 101c and 101d was 0.5 mm. At this time, the length of the drawing line of the laser beam was 10.38 mm. As a result, the time for erasing the solid image was 4.8 seconds, but the solid image at the boundary between adjacent regions was not sufficiently erased.

(Comparative Example 1-4)
A solid image was recorded and erased in the same manner as in Example 1-4, except that the overlapping width L of the adjacent areas 101a and 101b, 101b and 101c, 101c and 101d was 5.4 mm. At this time, the length of the drawing line of the laser beam was set to 14.05 mm. As a result, the solid image at the boundary between adjacent regions was sufficiently erased, but the time to erase the solid image was 6.9 seconds.

  Table 1 shows the evaluation results when the scanning directions of adjacent laser beams are the same in the thermoreversible recording medium 1.

表１から、実施例１−１〜１−７は、レーザ光を並列に走査する画像記録領域１０１を分割しなかった比較例１−１と比較して、レーザ光の照射エネルギー密度を増大させずに、ベタ画像を消去する時間を短縮できることがわかる。

From Table 1, Examples 1-1 to 1-7 increase the irradiation energy density of the laser beam as compared with Comparative Example 1-1 in which the image recording area 101 that scans the laser beam in parallel is not divided. It can be seen that the time for erasing the solid image can be shortened.

  On the other hand, in Comparative Examples 1-2 and 1-3, since L / S is 0 to 0.17, the solid image at the boundary portion between adjacent regions is not sufficiently erased.

  In Comparative Example 1-4, since L / S is 1.8, the time for deleting the solid image becomes longer.

(Example 2-1)
A solid image was recorded and then erased in the same manner as in Example 1-2 except that the scanning speed of the laser beam was 2400 mm / s and the scanning direction of the adjacent laser beam was reversed (see FIG. 1). As a result, the laser beam irradiation interval when the remaining amount of the solid image was 0.03 was 0.29 mm, and the time for erasing the solid image was 3.4 seconds. At this time, the solid image at the boundary between adjacent regions was sufficiently erased.

(Example 2-2)
A solid image was recorded and erased in the same manner as in Example 2-1, except that the overlapping width L of the adjacent regions 101a and 101b, 101b and 101c, 101c and 101d was set to 3.0 mm. At this time, the length of the drawing line of the laser beam was 12.25 mm. As a result, the laser beam irradiation interval when the remaining amount of the solid image was 0.03 was 0.28 mm, and the time for erasing the solid image was 4.1 seconds. At this time, the solid image at the boundary between adjacent regions was sufficiently erased.

(Example 2-3)
A solid image was recorded and erased in the same manner as in Example 2-1, except that the overlapping width L of the adjacent regions 101a and 101b, 101b and 101c, 101c and 101d was 4.2 mm. At this time, the length of the drawing line of the laser beam was 13.15 mm. As a result, the laser beam irradiation interval when the remaining amount of the solid image was 0.03 was 0.27 mm, and the time for erasing the solid image was 4.4 seconds. At this time, the solid image at the boundary between adjacent regions was sufficiently erased.

(Example 2-4)
Example except that the overlapping width of adjacent regions 101a and 101b, 101b and 101c, 101c and 101d is 0.8 mm, the scanning speed of the laser light is 1500 to 3000 mm / s, and the irradiation interval of the laser light is 0.20 mm. In the same manner as in 2-1, a solid image was recorded and then erased. At this time, the length of the drawing line of the laser beam was 10.6 mm. As a result, the scanning speed of the laser beam when the remaining amount of the solid image was 0.03 was 3670 mm / s, and the time for erasing the solid image was 3.4 seconds. At this time, the solid image at the boundary between adjacent regions was sufficiently erased.

(Comparative Example 2-1)
A solid image was recorded and then erased (see FIG. 2) in the same manner as in Example 2-1, except that the image recording area 101 scanned in parallel with laser light was not divided. At this time, the length of the drawing line of the laser beam was 40 mm. As a result, the irradiation interval of the laser beam when the remaining amount of the solid image was 0.03 was 0.19 mm, and the time for erasing the solid image was 4.6 seconds. At this time, the solid image at the boundary between adjacent regions was sufficiently erased.

(Comparative Example 2-2)
A solid image was recorded and erased in the same manner as in Example 2-1, except that the overlapping width L of the adjacent regions 101a and 101b, 101b and 101c, 101c and 101d was 0 mm. At this time, the length of the laser light drawing line was set to 10 mm. As a result, the time for erasing the solid image was 3.3 seconds, but the solid image at the boundary between adjacent regions was not sufficiently erased.

(Comparative Example 2-3)
A solid image was recorded and erased in the same manner as in Example 2-1, except that the overlapping width L of the adjacent regions 101a and 101b, 101b and 101c, 101c and 101d was 0.5 mm. At this time, the length of the drawing line of the laser beam was 10.38 mm. As a result, the time for erasing the solid image was 3.4 seconds, but the solid image at the boundary between adjacent regions was not sufficiently erased.

(Comparative Example 2-4)
A solid image was recorded and erased in the same manner as in Example 2-3 except that the overlapping width L of the adjacent regions 101a and 101b, 101b and 101c, 101c and 101d was 5.4 mm. At this time, the length of the drawing line of the laser beam was set to 14.05 mm. As a result, the solid image at the boundary between adjacent regions was sufficiently erased, but the time for erasing the solid image was 4.8 seconds.

  Table 2 shows the evaluation results when the scanning directions of the adjacent laser beams are reversed in the thermoreversible recording medium 1.

表２から、実施例２−１〜２−４は、レーザ光を並列に走査する画像記録領域１０１を分割しなかった比較例２−１と比較して、レーザ光の照射エネルギー密度を増大させずに、ベタ画像を消去する時間を短縮できることがわかる。

From Table 2, Examples 2-1 to 2-4 increase the irradiation energy density of the laser light as compared with Comparative Example 2-1, in which the image recording area 101 that scans the laser light in parallel is not divided. It can be seen that the time for erasing the solid image can be shortened.

  On the other hand, in Comparative Examples 2-2 and 2-3, since L / S is 0 to 0.17, the solid image at the boundary portion between adjacent regions is not sufficiently erased.

  In Comparative Example 2-4, since the L / S is 1.8, the time for deleting the solid image becomes longer.

(Example 3-1)
A solid image was recorded in the same manner as in Example 1-1 except that the thermoreversible recording medium 2 was used instead of the thermoreversible recording medium 1 and the output was 23 W.

  Next, the solid image was erased in the same manner as in Example 1-1 except that the scanning speed of the laser light was 1500 to 3000 mm / s and the irradiation interval of the laser light was 0.20 mm. At this time, the length of the drawing line of the laser beam was 20.3 mm, that is, the overlapping width L of the adjacent regions 101a and 101b was 0.6 mm. As a result, the scanning speed of the laser beam when the remaining amount of the solid image was 0.03 was 1830 mm / s, and the time for erasing the solid image was 7.0 seconds. At this time, the solid image at the boundary between adjacent regions was sufficiently erased.

(Comparative Example 3-1)
A solid image was recorded and then erased in the same manner as in Example 3-1, except that the image recording area 101 scanned in parallel with the laser beam was not divided. At this time, the length of the drawing line of the laser beam was 40 mm. As a result, the scanning speed of the laser beam when the remaining amount of the solid image was 0.03 was 1480 mm / s, and the time for deleting the solid image was 8.6 seconds. At this time, the solid image at the boundary between adjacent regions was sufficiently erased.

  Table 3 shows the evaluation results when the scanning directions of adjacent laser beams are the same in the thermoreversible recording medium 2.

表３から、実施例３−１は、レーザ光を並列に走査する画像記録領域１０１を分割しなかった比較例３−１と比較して、レーザ光の照射エネルギー密度を増大させずに、ベタ画像を消去する時間を短縮できることがわかる。

From Table 3, Example 3-1 is solid without increasing the irradiation energy density of the laser beam as compared with Comparative Example 3-1, which did not divide the image recording area 101 that scans the laser beam in parallel. It can be seen that the time to erase the image can be shortened.

DESCRIPTION OF SYMBOLS 1 Laser oscillator 2 Beam expander 3 Mask or aspherical lens 4 Galvanometer 4A Mirror 5 Scanning unit 6 f (theta) lens 101 Image recording area 101a, 101b, 101c, 101d, 101e, 101f Area 100, 100A, 100B, 100C Thermoreversible recording medium 110 Support 120, 120A, 120B Thermoreversible recording layer 130 Photothermal conversion layer L Overlap width

JP 2011-116116 A

Claims (7)

Image by scanning the laser beam in parallel to the thermoreversible recording medium which is recorded an image processing method for have a step of eliminating the image,
The process, a region for scanning the laser beam in parallel are divided into regions of multiple and to the direction of scanning the laser beam, scanning the laser beam in parallel to each of the divided plurality of regions And erasing the image by
Among the plurality of regions, adjacent regions have an overlap,
An image processing method, wherein a ratio of an overlapping width of the adjacent region to a spot diameter of the laser light is 0.20 or more and 1.6 or less.   The image processing method according to claim 1, wherein the scanning directions of the adjacent laser beams are the same.   The image processing method according to claim 1, wherein the scanning directions of the adjacent laser beams are opposite to each other.   The image processing method according to claim 1, wherein a direction in which the laser beam is scanned is a short direction of a region in which the laser beam is scanned in parallel.   5. The thermoreversible recording medium according to claim 1, wherein a thermoreversible recording layer containing a photothermal conversion material, a leuco dye, and a developer is formed on a support. Image processing method.   The image processing method according to claim 1, wherein the laser light has a wavelength of 700 nm to 2000 nm.   The image processing method according to claim 6, wherein the laser light is scanned in parallel using one or more selected from the group consisting of a YAG laser, a fiber laser, and a semiconductor laser.

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