JP4726137B2 - Image display medium and image forming apparatus - Google Patents

Description

This invention relates to images display medium and an image forming apparatus, and more particularly, the photochromic composition capable of repeatedly forming an image by heat treatment and light irradiation, an image forming apparatus using the image display medium and this .

There have been proposals for a composition using a photochromic compound that shows reversible color change by light irradiation, and a display medium or recording medium using the composition. However, a color image can be formed by light irradiation, and There has not yet been found any proposal with excellent practicality that can be rewritten and the formed image has sufficient stability to light.

  As a method for forming a color image using a photochromic compound, for example, in Patent Document 1, a photochromic property that develops yellow-orange by 254 nm ultraviolet light irradiation, red by 313 nm ultraviolet light irradiation, and bluish purple by 365 nm ultraviolet light irradiation. A method of mixing three kinds of diarylethene compounds and irradiating ultraviolet light of each wavelength has been proposed. In order to form a full-color image, it is necessary to control the extinction / color development of three or more photochromic compounds that develop the three primary colors (blue, green, red or yellow, magenta, cyan) with light. It is necessary to be able to select whether or not each material is colored according to the three types of ultraviolet light wavelength range, that is, three or more types of photochromic compounds that do not overlap in the absorption band in the ultraviolet region are required. Although the three primary colors must be shown in the state, no system of such compounds is found in practice. For practical use, it is necessary to consider not only the color development characteristics but also the repeated durability and heat / humidity stability, and it is very difficult to develop a material satisfying all of these.

  In Patent Document 2, three types of photochromic fulgide compounds showing yellow, magenta, and cyan in a colored state are irradiated with white light through a color positive film after coloring all photochromic compounds with 366 nm ultraviolet light. Thus, a method for obtaining a color image by selectively erasing each photochromic fulgide compound as necessary has been proposed. Although this method has the advantage that only one type of ultraviolet light source can be used, it requires a color positive film for the image to be formed, and it is not practical to prepare it each time. Not suitable for use in image output. Furthermore, the image formed in this way is gradually discolored by the illumination light and the image is lost.

  In Patent Document 3, a spiropyran compound having a long chain structure is dissolved or dispersed in a polymer and irradiated with ultraviolet light while being heated to 35 to 50 ° C. or heated after irradiation with ultraviolet light to change the colored state to light. In contrast, photochromic compositions that have been stabilized are proposed. In Patent Document 4, a heat-sensitive recording material using the photochromic composition is proposed. These are not originally intended for display applications. When trying to apply to display, the hue is limited to single color display. And more essentially, in the application to display, stabilization (image fixing) after image formation is completed by controlling the color-decoloring state of the photochromic compound contained in the display medium (the display layer). ), But stabilization occurs at a temperature of about 35 ° C., so stabilization may occur unexpectedly during image formation due to, for example, the living environment in the hot season or heat accumulation in the device. Therefore, appropriate image formation cannot be performed, and application to a display medium is not possible.

Including these, related proposals, that is, photochromic compounds can be used to form a color image by light irradiation, and the image can be rewritten, and the formed image has sufficient stability to light. There are no proposals for image display media and image forming methods that are excellent in practical use.
Japanese Patent Laid-Open No. 5-271649 JP 7-199401 A Japanese Unexamined Patent Publication No. 63-20787 JP-A-1-226387

  As a result of intensive studies in view of such situations and problems, we have reached the present invention.

  The present invention provides an image display medium and an image forming method that are excellent in practicality, such that a color image can be formed by light irradiation, the image can be rewritten, and the formed image has sufficient stability to light. Is intended to provide.

  The photochromic composition of the present invention includes a photochromic compound represented by the general formula (I) and a compound having a long chain structure represented by the general formula (II).

(However, R ₁ and R ₂ are independently an alkyl group having 12 or more carbon atoms, an alkanoyloxymethyl group, an alkoxy group, an alkoxycarbonyl group, an alkoxycarbonylalkyl group, a carboxyalkyl group, a hydroxyalkyl group, and an alkylphenyl group. And R _{3 to} R ₁₃ are independently hydrogen or a substituent.)

(However, R ₁₄ and R ₁₅ are independently hydrogen or an alkyl group, X is a structure having hydrogen bonding or associating properties, and a long chain structure having 12 or more carbon atoms as a whole.)
The image display medium of the present invention is characterized in that a display layer made of the above-described photochromic composition is formed on a support substrate.

  Furthermore, the image display medium of the present invention is characterized in that the display layer contains two or more kinds of photochromic compounds having different hues in the associated state.

  The image display medium of the present invention displays a first photochromic compound that exhibits a yellow hue in an associated state, a second photochromic compound that exhibits a magenta hue, and a third photochromic compound that exhibits a cyan hue. Each photochromic compound contained in the layer is composed of the above-described photochromic composition.

  In the image display medium of the present invention, the display layer includes a display layer containing only the first photochromic compound, a display layer containing only the second photochromic compound, and a display layer containing only the third photochromic compound. It is a laminated structure.

  The image forming apparatus of the present invention also includes a rotation driving means for rotating and driving an optical disc having an optical disc label recording surface on which the display layer of the image display medium described above is formed, and an ultraviolet ray partially on the optical disc label recording surface. An ultraviolet light irradiation means for irradiating light and a heating means for raising the temperature to a predetermined temperature necessary for image stabilization are provided.

  The image forming apparatus according to the present invention includes a rotation driving means for rotating and driving an optical disc having an optical disc label recording surface on which the display layer of the image display medium described above is formed, and a portion of the display layer of the optical disc label recording surface. UV light irradiation means for irradiating ultraviolet light, heating means for heating the display layer to a predetermined temperature necessary for image stabilization, and heating the display layer to a predetermined temperature required for erasing the formed image And heating means.

  The image forming apparatus of the present invention also includes a rotation driving means for rotating and driving an optical disc having an optical disc label recording surface on which the display layer of the image display medium described above is formed, and an ultraviolet ray is applied to the display layer of the optical disc label recording surface. UV light irradiating means for irradiating light, visible light irradiating means for irradiating visible light in a wavelength region corresponding to the maximum absorption wavelength of each photochromic compound in a colored state, and a display layer at a predetermined temperature required for image stabilization And heating means for raising the temperature.

  The image forming apparatus of the present invention also includes a rotation driving means for rotating and driving an optical disc having an optical disc label recording surface on which the display layer of the image display medium described above is formed, and an ultraviolet ray is applied to the display layer of the optical disc label recording surface. UV light irradiating means for irradiating light, visible light irradiating means for irradiating visible light in a wavelength region corresponding to the maximum absorption wavelength of each photochromic compound in a colored state, and a display layer at a predetermined temperature required for image stabilization It is characterized by comprising heating means for raising the temperature, and heating means for raising the temperature of the display layer to a predetermined temperature necessary for erasing the formed image.

According to the first aspect of the present invention, it is possible to obtain an image display medium capable of imparting sufficient stability to light without being affected by the use environment temperature or the temperature in the apparatus, and further capable of full color display. Become.

According to invention of Claim 2 , in addition to the above-mentioned effect, the suitable aggregate formation effect can be provided for every photochromic compound to be used.

According to the third aspect of the present invention, there is provided a monochrome image forming apparatus capable of imparting sufficient stability to light without being affected by an operating environment temperature or an apparatus internal temperature with respect to an optical disc type medium. can get.

According to the fourth aspect of the present invention, formation and erasure of a monochrome image capable of imparting sufficient stability to light without being affected by the use environment temperature or the apparatus internal temperature with respect to the optical disc type medium. A device capable of achieving the above is obtained.

According to the fifth aspect of the present invention, a monochrome image or a multicolor image that can give sufficient stability to light without being affected by the use environment temperature or the apparatus internal temperature with respect to the optical disc type medium. The forming apparatus is obtained.

According to the invention described in claim 6 , a monochrome image or a multicolor image that can give sufficient stability to light without being affected by the use environment temperature or the apparatus internal temperature with respect to the optical disc type medium. A device capable of forming and erasing is obtained.

  Embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals, and the description thereof will not be repeated in order to avoid duplication of description.

  First, the basic mechanism of an image display medium in which a display layer containing a photochromic compound is formed on a substrate and a method for forming a color image by light irradiation on the display layer will be described.

  FIG. 1 is a schematic diagram showing the configuration of an image display medium 1 used in the present invention.

  In the image display medium 1, a display layer including two or more types of photochromic compounds having different maximum absorption wavelengths in a colored state, that is, different colors recognized in a colored state, is formed on a support substrate 10. The structure shown in FIG. 1 is formed by laminating display layers 11, 12, and 13 containing three types of photochromic compounds having different maximum absorption wavelengths. The display layer 11 containing the first photochromic compound has the characteristic of the maximum absorption wavelength shown in FIG. 2A, and the display layer 12 containing the second photochromic compound is the maximum shown in FIG. The display layer 13 having the absorption wavelength characteristic and including the third photochromic compound is composed of each having the maximum absorption wavelength characteristic shown in FIG.

  In this, after coloring all kinds of photochromic compounds contained in the display layer by ultraviolet light irradiation, in the wavelength range corresponding to the visible absorption band of each colored photochromic compound (wavelength range near the maximum absorption wavelength) A desired color image is obtained by irradiating each predetermined region with light and selectively decoloring a corresponding photochromic compound. In the example shown in FIG. 1, the first display layer 11 is decolored with respect to the light with the wavelength A, the second display layer 12 is decolored with respect to the light with the wavelength B, and the light with the wavelength C is obtained. In contrast, the third display layer 13 is decolored.

  More specifically, the fact that the maximum absorption wavelength in the colored state is different means that the recognized color is different, and this maximum absorption wavelength only needs to be set according to the color to be used for display. In addition, the type of the photochromic compound may be set corresponding to the number of colors desired for display. By using photochromic compounds in which the hues in the colored state are yellow, magenta, and cyan, respectively, three primary colors for color display are formed.For example, by adjusting the degree of decoloration of each photochromic compound in the visible light irradiation step, It becomes possible to control the density of the color obtained by the photochromic compound, and the above-described image display method enables multicolor display with a wide color reproduction range.

  The above describes the case where an image is formed on an image display medium composed of a display layer containing two or more kinds of photochromic compounds having different maximum absorption wavelengths in a colored state. When an image display medium consisting of a display layer containing only one type of photochromic compound is targeted, a so-called monochrome image having a single color hue and a different density is formed. The basic method of forming an image by controlling the degree of color development of the photochromic compound contained is the same as in the case of forming a color image described above.

  In addition, even when the photochromic compound contained in the display layer is one type or when there are two or more types having different maximum absorption wavelengths in the colored state, the photochromic compound is in a predetermined region with respect to the state where all the photochromic compounds are decolored. A monochrome image can be formed by irradiating ultraviolet light to cause color development.

  The present invention can form a color image by light irradiation based on the image display medium in which the display layer containing the photochromic compound described above is formed on a substrate and a method of forming an image by light irradiation on the display medium. In addition, the present invention was obtained as a result of studying an image display medium and an image forming method that are excellent in practical use so that an image can be rewritten and the formed image has sufficient stability to light.

  The present invention will be described in detail below.

  One of the features of the present invention is to constitute a photochromic composition comprising a photochromic compound represented by the following general formula (I) and a compound having a long chain structure represented by the general formula (II).

(However, R ₁ and R ₂ are independently alkyl groups having 12 or more carbon atoms, alkanoyloxymethyl groups, alkoxy groups, alkoxycarbonyl groups, alkoxycarbonylalkyl groups, carboxyalkyl groups, hydroxyalkyl groups, alkylphenyl groups, etc. R _{3 to} R ₁₃ are each independently hydrogen or a substituent such as halogen, alkyl group, alkoxy group, alkoxycarbonyl group, dialkylamino group, methoxy group, cyano group, amino group, nitro group, etc. .)

(However, R ₁₄ and R ₁₅ are independently hydrogen or an alkyl group, and X is an ester group, an ether group, a carbonyl group, an amide group, an imide group, an azo group, a thio group, a urethane group, a urea group, or a diimide group. And a long chain structure having 12 or more carbon atoms as a whole.
Spiropyran photochromic compounds represented by the general formula (I) (for example, 6-cyano-1 ′, 3′-dihydro-3 ′, 3′-dimethyl-1′-octadecyl-8-docosanoyloxymethylspiro [2H— 1-benzopyran-2,2 ′-[2H] indole]) changes its color to a merocyanine structure when irradiated with ultraviolet light, forms a stable aggregate upon heating, and is decolored even when irradiated with visible light. Almost never happens. When this is used by being dispersed in a polymer, the formation efficiency of the aggregate by heating may be improved by adding a long-chain alkyl compound or the like. Although details of the mechanism such as contribution of long-chain alkyl compounds in this association promoting effect have not been elucidated, compounds having a long-chain structure represented by the general formula (II) (for example, 1,3-didodecyl urea, 1-decyl) -3-octadecyl urea, octadecanoic acid octadecanoylamide, pentanonic acid octadecylamide, octadecanoic acid octadecylamide, 18-pentatriacontanone, 13-hentriacontanone, etc.), a simple long-chain alkyl compound is added. It has been found that a higher temperature heat treatment is required to form the aggregates than in the case of the above.

  Although the detailed mechanism is unknown, in promoting the association of photochromic compounds, the key is to improve the thermal mobility of long-chain structural compounds by heating. Compared to simple long-chain alkyl compounds (n-alkanes), the general formula ( By using a structure having a strong self-association force such as the long chain structure represented by II), it is considered that the temperature required for improving the thermal mobility and exhibiting the association promoting effect is increased.

  The temperature varies depending on the structure of X in the general formula (II) and also on the structure of the photochromic compound. For example, at a temperature of about 35 to 45 ° C., the association promoting effect is hardly exhibited, and a temperature range higher than that. For example, it can be expressed at 50 to 60 ° C. As for the heat treatment temperature for forming the aggregate, practically, as described above, the aggregate formation does not occur at a temperature of about 35 to 40 ° C., and the aggregate formation occurs at a higher temperature range, for example, 45 ° C. or higher. Is often preferred.

  The upper limit of the heat treatment temperature is not particularly limited. However, when the treatment temperature is too high, the photochromic compound itself is thermally discolored and formation of aggregates is difficult to occur. Many.

  Regarding the length of the long-chain structure compound, that is, the total number of carbon atoms, in general, when the long-chain structure is shorter than 12, sufficient self-association is not exhibited. Also in this invention, when the carbon number as a whole long chain structure compound is shorter than 12, sufficient self-association property is not expressed. Therefore, it is necessary to be 12 or more because the association promoting effect is not exhibited. On the other hand, the upper limit of the length is not particularly limited. However, if the length is too long, the association promoting effect tends to be impaired.

  As the polymer, for example, those having relatively small polarity such as polystyrene, polyester, polymethyl methacrylate, vinyl chloride-vinylidene chloride copolymer, polyvinyl chloride, polyvinylidene chloride, and polyvinyl acetate are preferably used.

  About each ratio in the case of comprising the photochromic composition in this invention with the photochromic compound represented by general formula (I) / long-chain structure compound represented by general formula (II) / polymer, 100 parts by weight of polymer The photochromic compound is preferably 0.1 to 50 parts by weight, and the long chain structure compound is preferably 10 to 200 parts by weight.

  Another feature of the present invention is that an image display medium is formed by forming the above-described photochromic composition as a display layer on a support substrate.

  Materials for the supporting substrate include polyethylene terephthalate, polyethersulfone, polycarbonate, phenoxy resin, aromatic polyester, phenolic resin, epoxy resin, etc., or opaque materials formed by adding a white pigment thereto, and paper Materials can be used.

  The shape of the support substrate is not limited to a sheet shape, a card shape, or a film shape, and may be a block shape, for example, and the shape is not limited.

  Examples of the method for forming the display layer include a vapor deposition method in addition to the coating method, but the coating method is simple, and the photochromic compound, the long-chain structure compound, and the polymer material are both dissolved in a solvent, a printing method, The film may be applied by a method such as spin coating and dried to form a film. The display layer does not necessarily have to be formed on the entire support substrate, and may be formed on a part. About preferable thickness of a display layer, although it changes also with the density | concentration etc. of the photochromic compound contained in a photochromic composition, about 0.1-10 micrometers is preferable.

Another feature of the present invention is that the display layer of the image display medium includes two or more photochromic compounds having different hues in an associated state.
When one type of photochromic compound is used, there is also one type of hue that can be displayed, that is, monochrome display, but when two or more types of photochromic compounds having different hues are used, each photochromic compound is erased and discolored. By controlling and combining the states, a very large number of hues can be displayed.

  Another feature of the present invention is that, as shown in FIG. 1, the display layer of the image display medium 1 includes a display layer 11 containing a first photochromic compound that exhibits a yellow hue in an associated state, and a magenta hue. And a display layer 12 containing a second photochromic compound showing a cyan color, and a display layer 13 containing a third photochromic compound showing a cyan hue. As a result, the three primary colors necessary for color display are formed, and a full color image can be formed by controlling and combining the respective photochromic compound erasing and decoloring states.

  As described above, the photochromic compound represented by the general formula (I) changes its color to a merocyanine structure upon irradiation with ultraviolet light, forms a stable aggregate upon heating, and is decolored even when irradiated with visible light. Although it hardly occurs, the hue changes slightly because the absorption characteristics change before and after the aggregate formation. Considering this, it is necessary to set the photochromic compound by paying attention to the hue in the state in which the aggregate is formed.

  Examples of the photochromic compound exhibiting a yellow hue in the associated state include 1 ′, 3′-dihydro-5 ′-(dimethylamino) -3 ′, 3′-dimethyl-6-nitro-1′-octadecyl-8-docosa. Noyloxymethyl spiro [2H-1-benzopyran-2,2 ′-[2H] indole], 6-cyano-1 ′, 3′-dihydro-5 ′-(dimethylamino) -3 ′, 3′-dimethyl- 1'-octadecyl-8-docosanoyloxymethyl spiro [2H-1-benzopyran-2,2 '-[2H] indole] and the like.

  Examples of the photochromic compound exhibiting a magenta hue in the associated state include 5′-chloro-6-cyano-1 ′, 3′-dihydro-3 ′, 3′-dimethyl-1′-octadecyl-8-docosanoyloxymethyl. Spiro [2H-1-benzopyran-2,2 ′-[2H] indole], 5 ′, 7′-dichloro-1 ′, 3′-dihydro-3 ′, 3′-dimethyl-6-nitro-1′- And octadecyl-8-docosanoyloxymethyl spiro [2H-1-benzopyran-2,2 ′-[2H] indole].

  Examples of the photochromic compound exhibiting a cyan hue in the associated state include 6-cyano-1 ′, 3′-dihydro-3 ′, 3′-dimethyl-1′-octadecyl-8-docosanoyloxymethylspiro [2H-1]. -Benzopyran-2,2 '-[2H] indole], 5'-bromo-1', 3'-dihydro-3 ', 3'-dimethyl-6-nitro-1'-octadecyl-8-docosanoyloxymethyl Spiro [2H-1-benzopyran-2,2 ′-[2H] indole], 5 ′, 7′-dibromo-1 ′, 3′-dihydro-3 ′, 3′-dimethyl-6-nitro-1′- And octadecyl-8-docosanoyloxymethyl spiro [2H-1-benzopyran-2,2 ′-[2H] indole].

  Another feature of the present invention is that the display layer of the above-described image display medium, the display layer 11 of the image display medium 1 containing only the first photochromic compound exhibiting a yellow hue in the associated state, and magenta In other words, the display layer 12 including only the second photochromic compound exhibiting the above hue and the display layer 13 including only the third photochromic compound exhibiting the cyan hue are stacked.

  The photochromic compound represented by the general formula (I) changes to a merocyanine structure when irradiated with ultraviolet light, develops color, and further forms a stable aggregate by heating, as described above, in the presence of a long-chain structure compound. Although the formation efficiency of the coalescence is improved, it can be said that the formation of the aggregate is substantially possible due to the effect in the polymer. Depending on the structure of the photochromic compound, conditions such as the structure and concentration of the long-chain structure compound that can substantially form an aggregate may be different. In such a case, a display layer may be formed under appropriate conditions for each photochromic compound and stacked.

  An intermediate layer may be provided between the display layers. In the process of laminating each layer, depending on the method of forming the laminated film, the constituent elements of each layer may be mixed around the boundary of each layer, so providing an intermediate layer prevents such mixing, resulting in each layer In this case, it becomes possible to form an appropriate aggregate. The material for forming the intermediate layer is transparent or has a certain degree of resistance to the organic solvent used in the coating method suitably used for forming the display layer, even if it is colored or small. Are preferable, and silicone resin, PVA (polyvinyl alcohol), and the like can be given. The forming method is the same as that of the display layer, and any method may be used, but the coating method is simple.

  Next, the above-described image display medium and an apparatus for forming and erasing an image of the above-described image display medium, for example, on a sheet-like printing body or a recording surface formed on a label recording surface of an optical disc will be described. First, a method for forming and erasing an image will be described.

(Method of forming a monochrome image)
A step of partially irradiating the above-described image display medium (whether one or more photochromic compounds are contained in the display layer) with ultraviolet light according to image data, and a step of raising the temperature to a predetermined temperature required for the association By applying the above, it becomes possible to form a monochrome image. Further, the image can be erased by performing a process of raising the temperature to a predetermined temperature necessary for erasure.

  First, a monochrome image is created by partially irradiating UV light based on the data corresponding to the image to be formed, with all the photochromic compounds contained in the display layer decolored as the initial state. Is formed.

  Next, by raising the temperature of the display layer to a temperature of, for example, about 50 to 60 ° C., the photochromic compound contained in the display layer forms an aggregate, so that the monochrome image is stabilized and exposed to light such as illumination for a long time. However, the image will not fade or disappear. When the image is to be erased, the display layer is heated to a temperature of about 100 ° C., for example, and the association state of the photochromic compound contained in the display layer is solved and the color is erased to erase the image.

  As a method of partially irradiating ultraviolet light, a method of combining a lamp-shaped UV light source and an array-type or surface-type shutter, a method using a UV array light source capable of controlling irradiation ON / OFF by itself, or a UV laser Scan etc. are mentioned.

  As a means for raising the temperature to a predetermined temperature required for the meeting, conventional heaters such as a heat roller, a thermal head, a halogen heater, a ceramic heater, and a quartz tube heater can be used. In addition, the heating temperature and heating time of the photosensitive layer of the image display medium can be adjusted according to conditions such as the proximity distance to the image display medium and time, or the contact pressure and time. Therefore, they can also be used as means for raising the temperature to a predetermined temperature necessary for erasing.

(Method for forming a multicolor image)
A step of developing all the photochromic compounds contained in the display layer by irradiating the above-mentioned image display medium with ultraviolet light, and visible light in a wavelength region corresponding to the maximum absorption wavelength of each of the colored photochromic compounds. By applying a process of selectively erasing the photochromic compound by irradiation based on the image data and a process of raising the temperature to a predetermined temperature required for the association, the photochromic compound contained in the display layer is applied to one type of image display medium. On the other hand, a monochrome image is formed, and a multicolor image can be formed on an image display medium having two or more photochromic compounds contained in the display layer.

  First, all the photochromic compounds contained in the display layer are colored by irradiating the entire surface of the display layer with ultraviolet light. Next, by partially irradiating visible light in the wavelength region corresponding to the maximum absorption wavelength of each colored photochromic compound corresponding to the image to be formed, based on the image data, the photochromic compound is selectively decolored. A desired image is formed. Next, by raising the temperature of the display layer to a temperature of, for example, about 50 to 60 ° C., the photochromic compound contained in the display layer forms an aggregate, so that the image is stabilized and exposed to light such as illumination for a long time. The image will not fade or disappear. When it is desired to erase this image, for example, by raising the temperature of the display layer to a temperature of about 100 ° C., the association state of the photochromic compound contained in the display layer is solved and the color is erased to erase the image.

  As a method of irradiating the entire surface of the display layer with ultraviolet light, a mercury lamp or xenon lamp may be used in combination with an optical filter to extract ultraviolet light in a desired wavelength range, or in a specific wavelength range such as an LED or LD. A light-emitting element that emits light may be used.

  As a method of partially irradiating visible light, lamps having a configuration in which an optical filter is combined with a white light source may be used, or a light emitting element that emits light in a specific wavelength range such as an LED or LD may be used. Good. As a method of irradiating only a desired region, for example, a light source array is formed by relatively moving a light source array in which light emission surfaces capable of controlling on / off of irradiation for each minute region are continuously arranged, and an image display medium. This can also be achieved by controlling on / off of irradiation of each light emitting surface of the array.

  As a means for raising the temperature to a predetermined temperature required for the meeting, conventional heaters such as a heat roller, a thermal head, a halogen heater, a ceramic heater, and a quartz tube heater can be used. In addition, the heating temperature and heating time of the photosensitive layer of the image display medium can be adjusted according to conditions such as the proximity distance to the image display medium and time, or the contact pressure and time. Therefore, they can also be used as means for raising the temperature to a predetermined temperature necessary for erasing.

  Another feature of the present invention is that ultraviolet light irradiation means for partially irradiating the above-mentioned image display medium with ultraviolet light corresponding to the image data, and raising the display layer to a predetermined temperature necessary for image stabilization. It is to construct an apparatus having heating means for heating.

  The support substrate used for the image display medium in the present invention is not limited to a sheet shape, but may have any shape. Here, a configuration example and operation of an apparatus capable of forming and erasing a monochrome image will be illustrated with a sheet-like image display medium as an example. 3 will be described.

  FIG. 3 is a schematic diagram illustrating an example of an image forming apparatus that forms a monochrome image on a sheet-like image display medium according to a first embodiment of the image forming apparatus of the present invention.

  The sheet-like image display medium 1 according to the present invention is set on the sheet mounting table 26 of the image forming apparatus 20. The image display medium 1 is provided with a display layer containing a photochromic compound according to the present invention on a substrate 10. The color of the substrate 10 is white, and the image display medium 1 is white when the photochromic compound is not colored.

  The image display medium 1 is conveyed from the insertion port 21 into the apparatus 20 by the conveyance roller 22. The ultraviolet light irradiating means 24 forms a monochrome image by partially irradiating ultraviolet light corresponding to the image to be formed to cause color development. The ultraviolet light irradiation means 24 is constituted by a method of combining a lamp-shaped UV light source and an array-type or surface-type shutter, a method using a UV array light source capable of controlling ON / OFF of irradiation by itself, or a UV laser scanning. Is done.

  The image display medium 1 in which a monochrome image is formed on the display layer by the ultraviolet light irradiation unit 24 is further fed by the transport roller 22 and is heated to a predetermined temperature required for the meeting by the heating unit 25 to stabilize the image. It becomes. As a means for raising the temperature to a predetermined temperature necessary for the meeting, a heat roller, a thermal head, a halogen heater, a ceramic heater, a quartz tube heater, or the like is used.

  The image display medium 1 that has been subjected to image stabilization processing by the heating unit 24 is transported by the transport roller 23, discharged from the discharge port 24, and discharged onto the discharge tray 27.

  For example, it is possible to form a monochrome image by manufacturing the apparatus with such a configuration.

  Next, the optical disk label recording surface on which the display layer described above is provided, including an ultraviolet light irradiation means for partially irradiating ultraviolet light, and a heating means for raising the temperature to a predetermined temperature necessary for image stabilization, An apparatus for forming an image on an optical disk label recording surface will be described.

  In recent years, optical discs such as CDs and DVDs have become widespread as information recording media. Examples of the CD include a reproduction-only CD-ROM, a recordable CD-R, a rewritable CD-RW, and the like. As the DVD, a reproduction-only DVD-ROM, a recordable DVD-R, and a rewritable DVD. -RAM, DVD-RW, etc. For example, a recordable optical disc has an information recording layer. An optical disk having a label recording surface capable of recording characters and images by handwriting on a label recording surface opposite to the surface on the information recording layer is widely used.

  Once a character or image is recorded on the label recording surface by an ink jet printer or handwriting, the image or the like cannot be erased. In a rewritable optical disk, it is desirable that the label recording surface be rewritten correspondingly when the contents are rewritten. Therefore, if a recording layer made of the image display medium according to the present invention is provided on the label recording surface, image formation and erasure can be easily performed. Therefore, the present invention comprises an ultraviolet light irradiation means for partially irradiating the optical disk label recording surface with ultraviolet light, and a heating means for raising the temperature to a predetermined temperature necessary for image stabilization. It is an object of the present invention to provide an apparatus capable of forming an image and erasing it if necessary.

  A configuration example of an apparatus for forming an image on an optical disk label recording surface and an outline of the operation will be described with reference to FIG. FIG. 4 is a schematic diagram showing an apparatus for forming an image on an optical disk label recording surface, showing a second embodiment of the image forming apparatus of the present invention. A configuration example of an apparatus for forming an image on an optical disk label recording surface and an outline of the operation will be described with reference to FIG.

  For example, an apparatus that can fix the optical disk 100 and can control rotation is used as a base, such as an existing optical disk drive apparatus. A label recording surface 100a is provided on the surface of the optical disc 100 opposite to the information recording surface. The label recording surface 100a is provided with the above-described image recording medium according to the present invention. In this case, the optical disk forms the substrate 10 with the substrate.

  A heating means 110 and an ultraviolet light irradiation means 111 are provided so as to face the label recording surface 100a.

  To record an image, first, the optical disk 100 is rotated in the direction of the arrow in the figure, and the ultraviolet light irradiation means 111 forms a monochrome image by partially irradiating ultraviolet light corresponding to the image to be formed to cause color development. . Next, the heating means 110 raises the temperature to a predetermined temperature required for the meeting and stabilizes the image, whereby a monochrome image can be formed.

  The formation of an image on the optical disc label recording surface 100a is basically performed as described above. Actually, however, the rotational speed of the optical disc, the irradiation timing of ultraviolet light corresponding to the radial direction of the disc, and the like are image data. It is necessary to control according to.

  Next, a configuration example of an apparatus in which the above-described optical disk drive apparatus is provided with the image recording apparatus of the present invention will be described with reference to the block diagram of FIG.

  An optical disc apparatus provided with an image recording apparatus capable of forming an image on a label recording surface without resetting the optical disc with respect to the optical disc 100 provided with the image recording medium of the present invention on the label recording surface 100a of the optical disc. I will provide a.

  FIG. 5 is a block diagram showing a configuration of an optical disc apparatus provided with an image recording apparatus according to the second embodiment of the present invention.

  In FIG. 5, 120 is a drive mechanism unit, 123 is a spindle motor, 124 is an optical pickup, 127 is a feed unit, 111 is an ultraviolet light irradiation unit, 125 is a heating unit, 128 is a first analog processing unit, and 129 is a servo. Processing unit, 130 motor driving unit, 131 controller, 132 laser driving unit, 133 digital signal processing unit, 134 buffer memory, 135 second motor driving unit, 137 irradiation means driving unit, 138 second A servo processing unit 100 is an optical disk.

  The operation of the optical disc apparatus configured as described above according to an embodiment of the present invention will be described. In FIG. 5, the drive mechanism unit 120 includes a spindle motor 123 that rotates the optical disc 100, an optical pickup 124 that records or reproduces information on the information recording surface of the optical disc 100, and a label recording surface 100a of the optical disc. Ultraviolet light irradiation means 111 for forming a visible image by irradiating ultraviolet light, a feed unit 127 for moving the carriage on which the optical pickup 124 is mounted in the radial direction of the optical disk 100, and a predetermined temperature required for the association. It is comprised by the heating means 125 which heats up and stabilizes an image.

  The first analog signal processing unit 128 generates a focus error signal and a tracking error signal based on a signal output from an optical sensor (not shown) in the optical pickup 124 provided in the drive mechanism unit 120. And output to the servo processing unit 129.

  The servo processing unit 129 generates a lens position signal indicating the relative positional relationship between the objective lens of the pickup 124 and the carriage, and outputs the lens position signal to the first motor driving unit 130. The first motor drive unit 130 drives the optical pickup 124, the spindle motor 123, and the feed unit 127.

  The servo processing unit 129 includes an ON / OFF circuit, an arithmetic circuit, a filter circuit, an amplifier circuit, and the like, and performs focus / tracking control of the objective lens of the optical pickup 124 so that the light beam spot follows the information track of the optical disc 100. Further, feed control is performed using the low frequency component of the tracking error signal so that the objective lens is maintained at a substantially neutral position.

  The feed unit 127 includes a feed motor, a gear, a screw shaft (not shown), and the like, and the carriage moves in the radial direction of the optical disc 100 by rotating the feed motor.

  The digital signal processing unit 133 converts the analog signal sent from the first analog signal processing unit 128 into a digital signal, which is transmitted to each part of the controller 131, the laser driving unit 132, the ultraviolet light irradiation means driving unit 137, and the buffer memory 134. Send it out.

  The controller 131 controls the entire servo unit configured as described above. The first analog signal processing unit 128, the servo processing unit 129, the motor driving unit 130, and the digital signal processing units 133 and 137 are irradiation means. Signals sent from each part of the drive unit are input, calculation processing of these signals, etc. are performed, the result (signal) of this calculation process is sent to each part, each part is driven and processed, and control of each part is performed. Is what you do.

  The motor driving unit 130 outputs an FG pulse signal having a frequency corresponding to the number of rotations of the spindle motor 123 to a PLL circuit in the digital signal processing unit 13 using a back electromotive current obtained from the spindle motor 123.

  The PLL circuit multiplies the FG pulse signal and generates a PLL clock signal used for visible image formation. For example, when the spindle motor 123 generates n FG pulses while the optical disk rotates once, that is, when the optical disk rotates once, the PLL circuit generates a PLL clock signal obtained by multiplying the FG pulses.

  The digital signal processing unit 133 reads out data necessary for image formation indicating the gradation of one coordinate from the buffer memory 134 for each PLL clock signal, that is, every time the optical disk rotates by a certain angle, and the irradiation unit driving unit A lighting control signal is sent to 137.

  The ultraviolet light irradiation means 111 in this embodiment is configured to have a plurality of irradiation portions in a line shape in the radial direction of the optical disc 100. As the line-shaped ultraviolet light irradiation means 111, a combination of a lamp-shaped UV light source and an array-type shutter, or a UV array light source capable of controlling irradiation ON / OFF by itself is used. In the case of using a shutter, the irradiation driving means 137 controls the opening and closing of the shutter corresponding to the image data. When a UV array light source is used, the irradiation drive unit 137 controls ON / OFF.

  By the way, as shown in the conceptual diagram of the recording track on the label recording surface in FIG. 6, the optical disc 100 has a larger number of dots to be recorded in the outer peripheral direction. When the line-shaped ultraviolet light irradiation means 126 is used, the number of dots to be recorded is different between the inner peripheral side and the outer peripheral side. For this reason, the light emission part corresponding to the dot of the light irradiation means 126 of the inner peripheral side has fewer dots to be lit than the light emission part of the outer peripheral side. According to the example of FIG. 6, first, the dots corresponding to the L3 and L2 lines are turned on. At this time, the L1 line is not lit. Subsequently, when the optical disk 100 is rotated by one dot in the L3 line, the dot corresponding to the L3 line is turned on. At this time, the L1 and L2 lines are not lit. Subsequently, when the optical disk 100 is rotated by one dot of three lines, the dots corresponding to the L1, L2, and L3 lines are turned on. Further, when the optical disk 100 is rotated by one dot in the L3 line, the dots corresponding to the L2 and L3 lines are turned on. At this time, the L1 line is not lit.

  Thus, in this example, while the L3 line 4 dots are lit, the L2 line is controlled to be 3 dots and the L1 line is 1 dot, and the number of dots recorded on the inner and outer peripheral sides is different. Controlled to record.

  Next, an image recording operation on the label recording surface of the optical disc 100 will be described. When the optical disk 100 is inserted, the optical disk device rotates the spindle motor 123, starts the start-up process, applies focus servo and tracking servo, and performs disk discrimination.

  Next, a visible image recording operation on the label recording surface 100a is performed according to a user instruction. In the image recording operation on the label recording surface 100a, the disk rotation speed is first set.

  For setting the rotation speed of the optical disc 100, various input information of the user is transmitted from the host device to the controller 131 via the digital signal processing unit 133, and the controller 131 uses the information to transmit the motor via the servo processing unit 129. An instruction is issued to the drive unit 130 to operate the spindle motor 123. Further, the controller 131 transmits information to the ultraviolet light irradiation means 111 via the second servo processing unit 138 and the ultraviolet light irradiation driving means 137, and starts the lighting control operation of the ultraviolet light irradiation means 111.

  Next, the controller 131 detects each recording position linear velocity from the operation status of the spindle motor 123. The recording position linear velocity detection is calculated from the radial position of each irradiation section of the ultraviolet light irradiation means 126 and the rotational speed of the spindle motor 123.

  Subsequently, an image recording operation on the label recording surface 100a of the optical disc 100 is started. In the image recording operation on the label recording surface 100 a of the optical disc 100, first, the controller 131 issues an instruction to the digital signal processing unit 133 based on information already received from the user, which is transmitted via the ultraviolet irradiation driving means 137. Then, the light is transmitted in the order of the ultraviolet light irradiation means 111, and the desired irradiation part of the ultraviolet light irradiation means 111 is turned on.

  As the optical disk 1 rotates once, an image is recorded on the label recording surface 100 a of the optical disk 100. Here, when there is a limit in the output of the recording power of the ultraviolet light irradiation means 111, the optical disk 100 is rotated several times to perform the overlapping recording in which the recording operation is performed a plurality of times at the same position, and the overlapping recording is performed at the same position. What is necessary is just to comprise so.

  Then, after an image is recorded on the label recording surface 100a of the optical disc 100, an operation for stabilizing the image is started. In order to stabilize the image, the heating means 110 is heated to a predetermined temperature required for the meeting, the spindle motor 123 is driven, the optical disc 100 is rotated, and the heating means 110 passes below. When the temperature is raised to a predetermined temperature required for the meeting by passing once, the rotation of the optical disk 1 may be one degree. However, according to the power of the heating means 110, the optical disk 100 is rotated and stabilized a plurality of times. You can do it.

  Next explained is the third embodiment of the invention. In the third embodiment, as shown in FIG. 7, the above-mentioned image display medium is irradiated with ultraviolet light irradiation means 24 that partially irradiates ultraviolet light, and the display layer is raised to a predetermined temperature necessary for image stabilization. There are provided heating means 25b for heating, and heating means 25a for raising the temperature of the display layer to a predetermined temperature necessary for erasing the formed image.

  FIG. 7 is a schematic diagram showing an example of an image forming apparatus for forming and erasing a monochrome image on a sheet-like image display medium according to a third embodiment of the present invention.

  The sheet-like image display medium 1 according to the present invention is set on the sheet mounting table 26 of the image forming apparatus 20. The image display medium 1 is provided with a display layer containing a photochromic compound according to the present invention on a substrate 10. The color of the substrate 10 is white, and the image display medium 1 is white when the photochromic compound is not colored.

  The image display medium 1 is conveyed from the insertion port 21 into the apparatus 20 by the conveyance roller 22. If necessary, the temperature of the display layer is raised to a predetermined temperature necessary for erasing the image by the first heating means 25a to erase the image. Then, the ultraviolet light irradiation means 24 forms a monochrome image by partially irradiating ultraviolet light corresponding to the image to be formed to cause color development.

  The image display medium 1 on which the monochrome image is formed on the display layer by the ultraviolet light irradiation means 24 is further fed by the transport roller 22 and heated to a predetermined temperature required for the meeting by the second heating means 25b. The image is stabilized.

  The image display medium 1 for which the image stabilization processing has been completed by the second heating unit 25 b is conveyed by the conveyance roller 23, discharged from the discharge port 24, and discharged onto the discharge tray 27.

  For example, it is possible to form and erase a monochrome image by manufacturing the apparatus with such a configuration.

  In the above configuration example, the first heating means 25a for erasing and the second heating means 25b for stabilizing the image are provided separately, but only one heating means is used for each of the erasing process and the stabilizing process. You may use it properly by heating to temperature. In that case, the image display medium 1 is configured so that the image display medium 1 is conveyed to the heating unit again after the erasing step by the heating unit and the image forming step by the ultraviolet light irradiation unit 24 while being conveyed, and the stabilization step is performed. However, various configurations are conceivable.

  Next explained is the fourth embodiment of the invention. In this embodiment, as shown in FIG. 8, the optical disk label recording surface 100a on which the above-described display layer is formed is irradiated with ultraviolet light irradiation means 111 that partially irradiates ultraviolet light, and a predetermined necessary for image stabilization. It is to construct an apparatus including heating means 25b for raising the temperature of the display layer to a temperature, and heating means 25a for raising the temperature of the display layer to a predetermined temperature necessary for erasing the formed image.

  An example of the configuration of the apparatus is the same as that shown in FIGS. 4 and 5, the heating means 25b for raising the temperature of the display layer to a predetermined temperature necessary for image stabilization and the temperature of the display layer to a predetermined temperature necessary for erasing the formed image are different. It has heating means 25a.

  4 and 5, the same heating means may be used properly by heating to the respective temperatures required for the erasing process and the stabilizing process. In this case, for example, if necessary, the display layer is first heated to a predetermined temperature necessary for erasing the image, and the rotation of the disk is controlled to erase the image. Next, a monochrome image is formed by irradiating the ultraviolet light partially with the ultraviolet light irradiation means in correspondence with the image to be formed to cause color development. Next, the temperature is raised to a predetermined temperature required for the association by the heating means and the image is stabilized, whereby a monochrome image can be formed and erased.

  Next explained is the fifth embodiment of the invention. In this embodiment, as shown in FIG. 9, the above-described image display medium 1 corresponds to the ultraviolet light irradiation means 24 for irradiating the display layer with ultraviolet light, and the maximum absorption wavelength of each photochromic compound in the colored state. It comprises a visible light irradiating means 26 for irradiating visible light in the wavelength region, and a heating means 25 for raising the temperature of the display layer to a predetermined temperature necessary for image stabilization.

  A configuration example and operation of the fifth embodiment will be described with reference to FIG.

  The sheet-like image display medium 1 according to the present invention is set on the sheet mounting table 26 of the image forming apparatus 20. The image display medium 1 is provided with a display layer containing a photochromic compound according to the present invention on a substrate 10. The color of the substrate 10 is white, and the image display medium 1 is white when the photochromic compound is not colored.

  The image display medium 1 is conveyed from the insertion port 21 into the apparatus 20 by the conveyance roller 22. If necessary, the temperature of the display layer is raised to a predetermined temperature necessary for erasing the image by the first heating means 25a to erase the image. Then, all the photochromic compounds contained in the display layer are colored by the ultraviolet light irradiation means 24.

  Then, the colored image display medium 1 is sent to the visible light irradiation means 26 by the transport roller 22. The visible light irradiation means 26 partially irradiates visible light in a wavelength range corresponding to the maximum absorption wavelength of each colored photochromic compound corresponding to the image to be formed, and as shown in FIG. Is selectively erased. By selectively erasing, a desired image is formed.

  Next, the heating means 25 raises the display layer to a predetermined temperature necessary for the association to stabilize the image, and the image is discharged from the discharge port 29 to the outside of the apparatus. For example, it is possible to form a monochrome image or a multicolor image by manufacturing the apparatus with such a configuration.

  Next, a sixth embodiment of the present invention will be described. In this embodiment, as shown in FIG. 10, the optical disk label recording surface 100a on which the display layer is formed is irradiated with ultraviolet light irradiation means 111 for irradiating the display layer with ultraviolet light, and each photochromic compound in the colored state. A visible light irradiation means 126 for irradiating visible light in a wavelength region corresponding to the maximum absorption wavelength and a heating means 110 for raising the display layer to a predetermined temperature necessary for image stabilization are configured.

  A configuration example and operation of the apparatus according to the sixth embodiment will be described with reference to FIG.

  For example, an apparatus that can fix the optical disk 100 and can control rotation is used as a base, such as an existing optical disk drive apparatus. A label recording surface 100a is provided on the surface of the optical disc 100 opposite to the information recording surface. The label recording surface 100a is provided with the above-described image recording medium according to the present invention. The image recording medium 1 is configured to be capable of color display. As shown in FIG. 1, the image display medium 1 is configured in the same manner as having the first, second, and third photosensitive layers 11, 12, and 13. The first photosensitive layer 11 is a layer containing the fulgide compound having a maximum absorption wavelength in the range of 400 nm to less than 500 nm, and the second photosensitive layer 12 has a maximum absorption wavelength in the range of 500 nm to less than 600 nm. The layer containing the fulgide compound and the third photosensitive layer 13 are composed of a layer containing the fulgide compound having a maximum absorption wavelength in the range of 400 nm or more and less than 500 nm. The photosensitive layer thus formed is colorless and the color of the substrate 10 is white. This image display medium 1 is recognized as white by the observer.

  A heating unit 110, an ultraviolet light irradiation unit 111, and a visible light irradiation unit 126 are provided so as to face the label recording surface 100a. The visible light irradiation means 126 is configured to irradiate three types of visible light corresponding to the respective maximum absorption wavelengths in order to perform color display. For example, it is composed of three types of light emitting diode arrays. For example, the first light emitting diode array is irradiated with visible light having a center wavelength of 460 nm and a half width of 10 nm, and the second light emitting diode array is irradiated with visible light having a center wavelength of 560 nm and a half width of 10 nm. As such, it may be configured such that visible light having a center wavelength of 660 nm and a half width of 10 nm can be irradiated. By irradiating the above three types of light emitting diode arrays based on the corresponding image data, the display layer having the absorption wavelength in the irradiated visible light is selectively decolored and a color image is displayed.

  First, when the optical disk 100 is rotated in the direction of the arrow in the figure and the ultraviolet light irradiation means 111 partially irradiates the ultraviolet light corresponding to the image to be formed and develops color, all three display layers are colored and black. It becomes. Next, the visible light irradiation means 126 partially erases the photochromic compound by partially irradiating visible light in a wavelength region corresponding to the maximum absorption wavelength of each photochromic compound that is colored corresponding to the image to be formed. By doing so, a desired image is formed.

  Thereafter, the heating means 110 raises the temperature to a predetermined temperature required for the meeting and stabilizes the image, whereby a monochrome image or a multicolor image can be formed.

  Next, a sixth embodiment in which the above-described apparatus is applied to an optical disk drive apparatus will be described with reference to the block diagram of FIG. Although the basic configuration is the same as that shown in FIG. 5, the image shown in FIG. 5 was recorded by the irradiation of the ultraviolet light irradiation means 111. The one shown in FIG. The means 126 performs image recording based on the image data. The same components as those in FIG. 5 are denoted by the same reference numerals, and the description thereof is omitted here in order to avoid duplication of description.

  FIG. 11 is a block diagram showing a configuration of an optical disc apparatus provided with an image recording apparatus according to the sixth embodiment of the present invention.

  In FIG. 11, 120 is a drive mechanism unit, 123 is a spindle motor, 124 is an optical pickup, 125 is a feed unit, 111a is an ultraviolet light irradiation unit, 126 is a visible light irradiation unit, 125 is a heating unit, and 128 is a first unit. 1 analog processing unit, 129 servo processing unit, 130 motor driving unit, 131 controller, 132 laser driving unit, 133 digital signal processing unit, 134 buffer memory, 135 second motor driving unit, 136 first 2 is an analog signal processing unit, 137a is a visible light driving unit, 138 is a second servo processing unit, and 100 is an optical disk.

  In the embodiment shown in FIG. 5, image data is recorded by the ultraviolet light irradiation means. For this reason, it is configured to be able to be turned on / off corresponding to the pixel dot. On the other hand, in the embodiment shown in FIG. 11, the ultraviolet light irradiation means 111 a may color the entire image display medium 1 regardless of the pixel dots. For this reason, what is necessary is just to be able to irradiate the radial direction of the optical disc 100 in a line shape with a mercury lamp or the like. In this embodiment, the light irradiation based on the image data is performed by the visible light irradiation means 126. For this reason, as described above, the visible light irradiation means 126 is configured to be able to irradiate three types of visible light corresponding to the respective maximum absorption wavelengths in order to perform color display. In this embodiment, the first light-emitting diode array can emit visible light with a center wavelength of 460 nm and a half-value width of 10 nm, and the second light-emitting diode array emits visible light with a center wavelength of 560 nm and a half-value width of 10 nm. As a light-emitting diode array, a light-emitting diode array capable of irradiating visible light with a center wavelength of 660 nm and a half-value width of 10 nm is prepared, and the visible light irradiation means 126 is configured by these three light-emitting diode arrays. The visible light irradiating means 126 performs lighting control of each dot of the light emitting diode array corresponding to the image data by a driving signal given from the visible light driving unit 137a.

  Next, an image recording operation on the label recording surface of the optical disc 100 will be described. When the optical disk 100 is inserted, the optical disk device rotates the spindle motor 123, starts the start-up process, applies focus servo and tracking servo, and performs disk discrimination.

  Next, a visible image recording operation on the label recording surface 100a is performed according to a user instruction. In the image recording operation on the label recording surface 100a, the disk rotation speed is first set.

  In setting the rotation speed of the optical disc 100, various input information of the user is transmitted from the host device to the controller 131 via the digital signal processing unit 133, and the controller 131 receives the first information via the servo processing unit 129 based on the information. 1 An instruction is given to the motor drive unit 130 to operate the spindle motor 123. Further, the controller 131 transmits information to the ultraviolet light irradiation means 111 a and the visible light irradiation means 126 via the second servo processing unit 138 and the ultraviolet light irradiation driving means 137, and the ultraviolet light irradiation means 111 a and the visible light irradiation means 126. Starts lighting control operation.

  Next, the controller 131 detects each recording position linear velocity from the operation status of the spindle motor 123. The recording position linear velocity detection is calculated from the radial position of each irradiation section of the visible light irradiation means 126 and the rotation speed of the spindle motor 123.

  Subsequently, an image recording operation on the label recording surface 100a of the optical disc 100 is started. In the image recording operation on the label recording surface 100a of the optical disc 100, the label recording surface 100a is first irradiated with ultraviolet rays by the ultraviolet light irradiation means 11a. All three display layers are colored and become black by the ultraviolet irradiation. When the ultraviolet light irradiation means 111a detects that the optical disk 100 has made one rotation in the ultraviolet light irradiation means 111a, the irradiation stops. By controlling in this way, it is possible to prevent the color erased by the visible light irradiation means 126 from recurring.

  Based on the information already received from the user, the controller 131 first issues an instruction to the digital signal processing unit 133, which is transmitted in the order of the visible light irradiation means 126 via the visible light driving unit 137a, and the visible light. When a desired light emitting diode of the irradiation unit 126 is turned on, a display layer having an absorption wavelength in the irradiated visible light is selectively decolored, and a color image or a monochrome image is displayed.

  As the optical disk 1 rotates once, an image is recorded on the label recording surface 100 a of the optical disk 100. Here, when there is a limit to the recording power output of the visible light irradiation means 126, the optical disk 100 is rotated several times to perform over-recording in which the recording operation is performed a plurality of times at the same location, and the over-recording is performed at the same location. What is necessary is just to comprise so.

  Then, after an image is recorded on the label recording surface 100a of the optical disc 100, an operation for stabilizing the image is started. In order to stabilize the image, the heating means 110 is heated to a predetermined temperature required for the meeting, the spindle motor 123 is driven, the optical disc 100 is rotated, and the heating means 110 passes below. When the temperature is raised to a predetermined temperature required for the meeting by passing once, the rotation of the optical disk 1 may be one degree. However, according to the power of the heating means 110, the optical disk 100 is rotated and stabilized a plurality of times. You can do it. The heating means 110 uses a ceramic heater and is configured such that the temperature is controlled by the conveyance speed of the image display medium so that the display layer of the image display medium can be heated to 100 ° C. and 50 ° C., respectively.

  Next, as shown in FIG. 12, the seventh embodiment of the present invention includes an ultraviolet light irradiation means 24 for irradiating the display layer with ultraviolet light on the above-described image display medium, and each photochromic compound in a colored state. Necessary for erasing the formed image, visible light irradiating means 26 for irradiating visible light in a wavelength region corresponding to the maximum absorption wavelength of light, heating means 25b for raising the display layer to a predetermined temperature necessary for image stabilization, and The heating means 25a for raising the temperature of the display layer to a predetermined temperature is provided.

  FIG. 12 is a schematic diagram showing an example of an image forming apparatus for performing multicolor image formation or monochrome image formation and erasure on a sheet-like image display medium according to a seventh embodiment of the present invention.

  The sheet-like image display medium 1 according to the present invention is set on the sheet mounting table 26 of the image forming apparatus 20. The image display medium 1 is provided by laminating three display layers containing the photochromic compound according to the present invention on a substrate 10. The color of the substrate 10 is white, and the image display medium 1 is white when the photochromic compound is not colored.

  The image display medium 1 is conveyed from the insertion port 21 into the apparatus 20 by the conveyance roller 22. If necessary, the temperature of the display layer is raised to a predetermined temperature necessary for erasing the image by the first heating means 25a to erase the image. Then, the ultraviolet light irradiation means 24 irradiates the ultraviolet light to cause all the photochromic compounds contained in the display layer to develop color.

  The visible light irradiation means 26 partially irradiates visible light in a wavelength region corresponding to the maximum absorption wavelength of each colored photochromic compound to selectively erase the photochromic compound, thereby forming a desired image. .

  The image display medium 1 on which the image is formed on the display layer is further fed by the conveying roller 22, and the temperature is raised to a predetermined temperature required for the meeting by the second heating means 25b to stabilize the image.

  The image display medium 1 for which the image stabilization processing has been completed by the second heating unit 25 b is conveyed by the conveyance roller 23, discharged from the discharge port 24, and discharged onto the discharge tray 27.

  For example, by manufacturing the device with such a configuration, for example, by manufacturing the device with such a configuration, a color image or a monochrome image can be formed and erased.

  In the above configuration example, the first heating means 25a for erasing and the second heating means 25b for stabilizing the image are provided separately, but only one heating means is used for each of the erasing process and the stabilizing process. You may use it properly by heating to temperature. In that case, the image display medium 1 is configured so that the image display medium 1 is conveyed to the heating unit again after the erasing step by the heating unit and the image forming step by the ultraviolet light irradiation unit 24 while being conveyed, and the stabilization step is performed. However, various configurations are conceivable.

  Next, an eighth embodiment of the present invention will be described. In this embodiment, as shown in FIG. 13, the optical disk label recording surface 100a on which the display layer is formed is irradiated with ultraviolet light irradiation means 111 for irradiating the display layer with ultraviolet light, and each photochromic compound in a colored state. Visible light irradiating means 126 for irradiating visible light in a wavelength region corresponding to the maximum absorption wavelength, heating means 125b for raising the display layer to a predetermined temperature necessary for image stabilization, and necessary for erasing the formed image It is to construct an apparatus provided with heating means 125a for raising the temperature of the display layer to a predetermined temperature.

  An example of the configuration of the apparatus is the same as that shown in FIGS. 10 and 11, the heating means 125b for raising the temperature of the display layer to a predetermined temperature necessary for image stabilization, and the temperature of the display layer are raised to a predetermined temperature necessary for erasing the formed image. It has heating means 125a.

  As an example of the configuration of the apparatus, the same configuration as that shown in FIG. 12 may be used so that the same heating means is heated to the respective temperatures required for the erasing step and the stabilizing step. In this case, for example, if necessary, the display layer is first heated to a predetermined temperature necessary for erasing the image, and the rotation of the optical disc 100 is controlled to erase the image. Next, all the photochromic compounds contained in the display layer are colored by the ultraviolet light irradiation means 111, and then the maximum absorption wavelength of each photochromic compound colored by the visible light irradiation means 126 corresponding to the image to be formed. A desired image is formed by partially irradiating the photochromic compound by partially irradiating visible light in a wavelength region corresponding to the above. Next, it is possible to form a monochrome image or a multi-color image by stabilizing the image by raising the temperature to a predetermined temperature required for the association by the heating means.

  About a heating means, as shown in FIG. 13, it is good also as a structure which provides the heating means for exclusive use for an erasing process and a stabilization process one by one.

  As shown in FIG. 14, the ninth embodiment of the present invention is an apparatus provided with heating means 25 for raising the temperature of the display layer to a predetermined temperature necessary for erasing the formed image with respect to the above-mentioned image display medium. It constitutes.

  A configuration example and operation of the apparatus will be described with reference to FIG.

  When the image display medium 1 is conveyed into the apparatus from the insertion port 21 by the conveying roller 22, the heating layer 25 raises the display layer to a predetermined temperature necessary for erasing the image, and the image is erased. Discharged from the device. As another configuration example, as shown in FIG. 15, a plurality of image display media 1 subjected to the erasing process may be stored in the apparatus and taken out of the apparatus as necessary.

  In the tenth embodiment of the present invention, as shown in FIG. 16, the temperature of the display layer is raised to a predetermined temperature necessary for erasing the formed image with respect to the optical disc label recording surface 110a on which the display layer is formed. The apparatus provided with the heating means 110 to perform is comprised.

  A configuration example and operation of the apparatus will be described with reference to FIG. An apparatus that can fix the optical disk 100 and can control the rotation like the existing optical disk drive is used as a base, and the heating means 110 is provided. The disc 100 to be erased is set in the apparatus, and the display layer is heated to a predetermined temperature necessary for erasing the image by the heating means 110 and the rotation of the disc is controlled to erase the image.

  Alternatively, erasing can be performed using an apparatus having a configuration similar to that shown in FIGS.

  Hereinafter, the present invention will be specifically described based on examples.

(Example 1)
As a photochromic compound, 5′-bromo-1 ′, 3′-dihydro-3 ′, 3′-dimethyl-6-nitro-1′-octadecyl-8-docosanoyloxymethylspiro [2H-1-benzopyran-2, 2 ′-[2H] indole] (hereinafter referred to as “PC1”) was used, 1,3-didodecylurea was used as the long-chain structure compound, and polymethyl methacrylate was used as the polymer. 20 parts by weight of 1,3-didodecyl urea and 80 parts by weight of polymethyl methacrylate were added to 20 parts of PC1. Using toluene as a solvent, a coating solution was prepared to produce a cast film (2 μm) on a quartz substrate.

  When the absorption spectrum before light irradiation was measured, the absorption band was recognized in the range of 300-400 nm, and it was colorless.

  When this was irradiated with 366 nm ultraviolet light extracted from a high-pressure mercury lamp, it developed blue violet, and the maximum absorption wavelength of the absorption spectrum was 630 nm. When this was heat-processed at 40 degreeC with the heat roller, the hue changed and the maximum absorption wavelength of the absorption spectrum was 645 nm.

  When this was again heat-treated again at 100 ° C. with a heat roller, it returned to colorless and no absorption was observed in the visible region.

  Next, a cast film having the same formulation as above is formed on a white PET (polyethylene terephthalate) substrate (thickness: 188 μm), and a PVA (polyvinyl alcohol) film (2 μm) is further formed as a protective layer. Produced. Since the display layer formed in this way is colorless and the color of the substrate is white, the produced image display medium was recognized as white by the observer.

  Next, after irradiating the display layer of this image display medium with 366 nm ultraviolet light again to saturate the color reaction, it was heated to 40 ° C. with a heat roller, but no change was seen in the display layer. When 100,000 Lx white light was irradiated, the color disappeared in a few minutes.

  The display layer of this image display medium was again irradiated with 366 nm ultraviolet light to saturate the coloring reaction, and then heated to 50 ° C. with a heat roller. As a result, the hue of the display layer changed, and this was changed to 100,000 Lx. Even when irradiated with white light for 24 hours, no change was observed in the colored state.

(Comparative Example 1)
An image display medium was produced in the same manner as in Example 1 except that the long-chain structure compound was not used. After irradiating the display layer of this image display medium with ultraviolet light of 366 nm to saturate the coloring reaction, the heat treatment was carried out at 35 ° C., 40 ° C., 45 ° C., and 50 ° C. with a heat roller. No change was observed in the display layer, and the color disappeared in several minutes when irradiated with white light of 100,000 Lx.

(Comparative Example 2)
An image display medium was produced in the same manner as in Example 1 except that n-octadecane was used in place of 1,3-didodecylurea as the long-chain structure compound. After irradiating the display layer of this image display medium with ultraviolet light of 366 nm to saturate the coloring reaction, the heat treatment was carried out at 35 ° C., 40 ° C., 45 ° C., and 50 ° C. with a heat roller. Also, the hue of the display layer was changed, and no change was observed in the colored state even when irradiated with white light of 100,000 Lx for 24 hours.

(Example 2)
As a photochromic compound, 5′-chloro-6-cyano-1 ′, 3′-dihydro-3 ′, 3′-dimethyl-1′-octadecyl-8-docosanoyloxymethylspiro [2H-1-benzopyran-2, 2 ′-[2H] indole] (hereinafter referred to as “PC2”) was used, 1,3-didodecylurea was used as the long-chain structure compound, and polymethyl methacrylate was used as the polymer. 20 parts by weight of 1,3-didodecyl urea and 80 parts by weight of polymethyl methacrylate were added to 20 parts of PC2. Using toluene as a solvent, a coating solution was prepared to produce a cast film (2 μm) on a quartz substrate.

  When the absorption spectrum before light irradiation was measured, the absorption band was recognized in the range of 300-400 nm, and it was colorless.

  When this was irradiated with 366 nm ultraviolet light extracted from a high pressure mercury lamp, it developed blue-violet and the maximum absorption wavelength of the absorption spectrum was 570 nm. When this was heat-processed at 40 degreeC with the heat roller, the hue changed and the maximum absorption wavelength of the absorption spectrum was 532 nm.

  When this was again heat-treated again at 100 ° C. with a heat roller, it returned to colorless and no absorption was observed in the visible region.

  Next, a cast film (2 μm) having the same formulation as above is formed on a white PET (polyethylene terephthalate) substrate (thickness: 188 μm), and a PVA (polyvinyl alcohol) film (2 μm) is further formed as a protective layer. A display medium was produced. Since the display layer formed in this way is colorless and the color of the substrate is white, the produced image display medium was recognized as white by the observer.

  Next, after irradiating the display layer of this image display medium with 366 nm ultraviolet light again to saturate the color reaction, it was heated to 40 ° C. with a heat roller, but no change was seen in the display layer. When 100,000 Lx white light was irradiated, the color disappeared in a few minutes.

  The display layer of this image display medium was again irradiated with 366 nm ultraviolet light to saturate the coloring reaction, and then heated to 50 ° C. with a heat roller. As a result, the hue of the display layer changed, and this was changed to 100,000 Lx. Even when irradiated with white light for 24 hours, no change was observed in the colored state.

(Example 3)
PC1 and PC2 were used as the photochromic compound, 1,3-didodecylurea was used as the long-chain structure compound, and polymethyl methacrylate was used as the polymer. 20 parts by weight of 1,3-didodecyl urea and 80 parts by weight of polymethyl methacrylate were added to 20 parts by weight of PC1 and PC2, respectively. A coating solution is prepared using toluene as a solvent, a cast film (2 μm) is formed on a white PET (polyethylene terephthalate) substrate (thickness: 188 μm), and a PVA (polyvinyl alcohol) film (2 μm) is formed as a protective layer. Thus, an image display medium was produced. Since the display layer formed in this way is colorless and the color of the substrate is white, the produced image display medium was recognized as white by the observer.

  When the display layer of this image display medium was irradiated with 366 nm ultraviolet light, both PC1 and PC2 developed color and exhibited a blue color. Further, when this was irradiated with white light, the display layer became colorless and transparent again, so that the image display medium was recognized as white.

  This image display medium was again irradiated with 366 nm ultraviolet light to develop a color, and then a part thereof was irradiated with visible light having a center wavelength of 630 nm and a half-value width of 10 nm. Had a magenta color. Moreover, when another part was irradiated with visible light having a center wavelength of 570 nm and a half-value width of 10 nm, PC2 was selectively decolored and the irradiated part was bluish purple. These were heat-treated at 40 ° C. with a heat roller, but no change was observed in the display layer, and when this was irradiated with 100,000 Lx of white light, the whole was decolored in a few minutes.

  This image display medium was again irradiated with 366 nm ultraviolet light to develop a color, and then a part thereof was irradiated with visible light having a center wavelength of 630 nm and a half-value width of 10 nm. Had a magenta color. Moreover, when another part was irradiated with visible light having a center wavelength of 570 nm and a half-value width of 10 nm, PC2 was selectively decolored and the irradiated part was bluish purple. When these were heat-treated with a heat roller at 50 ° C., the reddish purple part exhibited magenta and the blue-purple part exhibited cyan. Even when they were irradiated with white light of 100,000 Lx for 24 hours, no change was observed in hue and color density.

Example 4
As a photochromic compound, 1 ′, 3′-dihydro-5 ′-(dimethylamino) -3 ′, 3′-dimethyl-6-nitro-1′-octadecyl-8-docosanoyloxymethylspiro [2H-1-benzopyran -2,2 '-[2H] indole] (hereinafter referred to as "PC3"), octadecanoic acid octadecanoylamide was used as the long-chain structure compound, and polymethyl methacrylate was used as the polymer. 20 parts by weight of octadecanoic acid octadecanoylamide was added to 20 parts by weight of PC3, and 80 parts by weight of polymethyl methacrylate was added. Using toluene as a solvent, a coating solution was prepared to produce a cast film (2 μm) on a quartz substrate. When the absorption spectrum before light irradiation was measured, the absorption band was recognized in the range of 300-400 nm, and it was colorless.

  When this was irradiated with 366 nm ultraviolet light extracted from a high-pressure mercury lamp, it was colored red and the maximum absorption wavelength of the absorption spectrum was 495 nm. When this was heat-treated at 40 ° C. with a heat roller, the hue changed to yellow and the maximum absorption wavelength of the absorption spectrum was 465 nm.

  When this was again heat-treated again at 100 ° C. with a heat roller, it returned to colorless and no absorption was observed in the visible region.

  Next, a cast film (2 μm) having the same formulation as above is formed on a white PET (polyethylene terephthalate) substrate (thickness: 188 μm), and a PVA (polyvinyl alcohol) film (2 μm) is further formed as a protective layer. A display medium was produced. Since the display layer formed in this way is colorless and the color of the substrate is white, the produced image display medium was recognized as white by the observer.

  Next, after irradiating the display layer of this image display medium with 366 nm ultraviolet light again to saturate the color reaction, it was heated to 40 ° C. with a heat roller, but no change was seen in the display layer. When 100,000 Lx white light was irradiated, the color disappeared in a few minutes.

  The display layer of this image display medium was again irradiated with 366 nm ultraviolet light to saturate the color reaction and then heated to 50 ° C. with a heat roller. As a result, the hue of the display layer changed to yellow. Even when Lx white light was irradiated for 24 hours, no change was observed in the colored state.

  20 parts by weight of 1,3-didodecylurea was added to 20 parts by weight of PC1, and 80 parts by weight of polymethyl methacrylate was added. A coating solution is prepared using toluene as a solvent, a cast film (2 μm) is formed on a white PET (polyethylene terephthalate) substrate (thickness: 188 μm), and an intermediate layer (2 μm) made of PVA is passed through it. 20 parts by weight of 1,3-didodecylurea was added to 20 parts by weight of PC2, and 80 parts by weight of polymethyl methacrylate was added. A cast film (2 μm) is formed from a coating solution using toluene as a solvent, and octadecanoic acid octadecanoylamide is further added to 20 parts by weight of PC3 through an intermediate layer (2 μm) of PVA. 20 parts by weight, 80 parts by weight of polymethyl methacrylate are added, a cast film (2 μm) is formed with a coating solution using toluene as a solvent, and a PVA film (2 μm) is further formed as a protective layer to display an image. A medium was made. Since the display layer formed in this way is colorless and the color of the substrate is white, the produced image display medium was recognized as white by the observer.

  When the display layer of this image display medium was irradiated with 366 nm ultraviolet light, all of PC1, PC2 and PC3 were colored and black. Further, when this was irradiated with white light, the display layer became colorless and transparent again, so that the image display medium was recognized as white.

  This image display medium was again irradiated with 366 nm ultraviolet light to develop a color, and then a part thereof was irradiated with visible light having a center wavelength of 500 nm and a half-value width of 10 nm. Exhibited a blue color. Moreover, when another part was irradiated with visible light having a center wavelength of 570 nm and a half-value width of 10 nm, PC2 was selectively decolored, and the irradiated portion was bluish purple. Further, when another portion was irradiated with visible light having a center wavelength of 630 nm and a half-value width of 10 nm, PC1 was selectively decolored and the irradiated portion was reddish purple. Further, when this was irradiated with white light, the display layer became colorless and transparent again, so that the image display medium was recognized as white.

  This image display medium was again irradiated with 366 nm ultraviolet light to develop a color, and then a part thereof was irradiated with visible light having a center wavelength of 500 nm and a half-value width of 10 nm. Exhibited a bluish green color. Moreover, when another part was irradiated with visible light having a center wavelength of 570 nm and a half-value width of 10 nm, PC2 was selectively decolored, and the irradiated portion was bluish purple. Further, when another portion was irradiated with visible light having a center wavelength of 630 nm and a half-value width of 10 nm, PC1 was selectively decolored and the irradiated portion was reddish purple. These were heat-treated at 40 ° C. with a heat roller, but no change was observed in the display layer, and when this was irradiated with 100,000 Lx of white light, the whole was decolored in a few minutes.

  This image display medium was again irradiated with 366 nm ultraviolet light to develop a color, and then a part thereof was irradiated with visible light having a center wavelength of 500 nm and a half-value width of 10 nm. Exhibited a bluish green color. Moreover, when another part was irradiated with visible light having a center wavelength of 570 nm and a half-value width of 10 nm, PC2 was selectively decolored, and the irradiated portion was bluish purple. Further, when another portion was irradiated with visible light having a center wavelength of 630 nm and a half-value width of 10 nm, PC1 was selectively decolored and the irradiated portion was reddish purple. When these were heat-processed to 50 degreeC with the heat roller, the blue-green part showed blue, the blue-purple part showed green, and the red-purple part showed red. Even when they were irradiated with white light of 100,000 Lx for 24 hours, no change was observed in hue and color density.

(Example 5)
An apparatus capable of forming and erasing an image having the configuration shown in FIG. 7 was produced. The first heating means 25a for image erasure and the second heating means 25b for image stabilization both use a ceramic heater, so that the display layer of the image display medium can be heated to 100 ° C. and 50 ° C., respectively. The temperature was controlled by the transfer speed. A UV-LED array (380 nm, 200 dpi) was used as the ultraviolet light irradiation means.

  When an image was formed on the image display medium produced in Example 1 and Example 4 using the apparatus produced in this example, a monochrome monochrome image and a black monochrome image were formed respectively, and 100,000 Lx of these were formed. Even when irradiated with white light for 24 hours, no change was observed in hue and color density. In addition, these image display media can be rewritten many times.

(Example 6)
An apparatus capable of forming and erasing an image having the configuration shown in FIG. 4 was produced. The first heating means for erasing the image and the second heating means for stabilizing the image both use a ceramic heater and transport the image display medium so that the display layer of the image display medium can be heated to 100 ° C. and 50 ° C., respectively. The temperature was controlled by the speed. Black light was used as the ultraviolet light irradiation means, and an RGB-LED array (500 nm, 570 nm, 640 nm, 200 dpi) was used as the visible light irradiation means.

  When an image was formed on the image display medium produced in Example 4 using the apparatus produced in this example, a full-color image was formed, and even if it was irradiated with white light of 100,000 Lx for 24 hours, the hue was There was no change in color density. In addition, these image display media can be rewritten many times.

(Example 7)
Utilizing an existing optical disk drive device, a heating means 110 and an ultraviolet light irradiation means 111 are provided as shown in FIG. 4, and the optical disk-like image display medium is modified so that the rotation speed of the disk can be controlled. An apparatus capable of image formation and image erasure was produced. A ceramic heater is used as the heating means, and the temperature is controlled so that the display layer can be raised to 100 ° C. in the image erasing process and the display layer can be raised to 50 ° C. in the image stabilization process. I made it. As the ultraviolet light irradiation means 111, a UV-LED array (380 nm, 200 dpi) was used. As an image forming (rewriting) procedure, an image erasing step is first performed by a heating unit, an image forming step is subsequently performed by an ultraviolet light irradiation unit, and finally an image stabilization step is performed by a heating unit. .

  When an image was formed on an image display medium produced by forming a display layer on the label recording surface of an optical disc in the same manner as in Example 2 and Example 4 using the apparatus produced in this example, each color was magenta. In addition, black and white monochrome images were formed, and even when they were irradiated with white light of 100,000 Lx for 24 hours, no change was observed in hue and color density. In addition, these image display media can be rewritten many times.

(Example 8)
Using an existing optical disk drive device, a heating means, an ultraviolet light irradiation means 111 and a visible light irradiation means 126 are provided as shown in FIG. 10, and the optical disk shape is modified so that the rotational speed of the disk can be controlled. An apparatus capable of forming and erasing an image on the image display medium was prepared. A ceramic heater is used as the heating means 110, and the temperature is controlled so that the display layer can be raised to 100 ° C. in the image erasing process, and the display layer can be raised to 50 ° C. in the image stabilization process. I did it. As the ultraviolet light irradiation means 111, a UV-LED (380 nm) was used, and as the visible light irradiation means 126, an RGB-LED array (500 nm, 570 nm, 640 nm, 200 dpi) was used. As a procedure for image formation (rewriting), first, an image erasing step is performed by the heating unit 110, and then an image forming step is performed by full color development by the ultraviolet light irradiation unit 111 and selective decoloring by the visible light irradiation unit 126, Finally, the image stabilization process is performed by the heating means.

  When an image was formed on an image display medium produced by forming a display layer on the label recording surface of an optical disc in the manner of Example 4 using the apparatus produced in this example, full-color images were formed. No change in hue and color density was observed even when irradiated with white light of 100,000 Lx for 24 hours. In addition, these image display media can be rewritten many times.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiments but by the scope of claims for patent, and is intended to include meanings equivalent to the scope of claims for patent and all modifications within the scope.

  The present invention can be used for so-called electronic paper, CD, and DVD label surfaces.

It is a schematic diagram which shows the structure of the image display medium used for this invention. It is a schematic diagram which shows the relationship between the light absorbency of a photochromic compound, and a wavelength. 1 is a schematic diagram illustrating an image forming apparatus according to a first embodiment of the present invention, which forms a monochrome image on a sheet-like image display medium. FIG. FIG. 5 is a schematic diagram illustrating an apparatus for forming an image on an optical disc label recording surface according to a second embodiment of the image forming apparatus of the present invention. FIG. 5 is a block diagram illustrating an image forming apparatus according to a second embodiment of the present invention, in which the image recording apparatus of the present invention is provided in an optical disk drive device. It is a conceptual diagram of the recording track of a label recording surface. FIG. 9 is a schematic diagram illustrating an image forming apparatus that forms a monochrome image and erases a sheet-like image display medium according to a third embodiment of the present invention. FIG. 10 is a schematic diagram illustrating an apparatus for forming an image on an optical disc label recording surface according to a fourth embodiment of the image forming apparatus of the present invention. FIG. 10 is a schematic diagram illustrating an image forming apparatus for forming and erasing a monochrome image on a sheet-like image display medium according to a fifth embodiment of the present invention. FIG. 10 is a schematic diagram illustrating an apparatus for forming an image on an optical disc label recording surface according to a sixth embodiment of the image forming apparatus of the present invention. FIG. 10 is a block diagram illustrating an image forming apparatus according to a sixth embodiment of the present invention, in which the image recording apparatus of the present invention is provided in an optical disk drive device. FIG. 9 is a schematic diagram illustrating an image forming apparatus according to a seventh embodiment of the present invention, which performs multicolor image formation or monochrome image formation and deletion on a sheet-like image display medium. FIG. 10 is a schematic diagram illustrating an image forming apparatus according to an eighth embodiment of the present invention, which forms an image on an optical disc label recording surface. 1 is a schematic diagram showing an image erasing apparatus of the present invention. 1 is a schematic diagram showing an image erasing apparatus of the present invention. 1 is a schematic diagram showing an image erasing apparatus of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image display medium 10 Support base | substrate 11, 12, 13 Display layer 24 Ultraviolet light irradiation means 25 Heating means 26 Visible light irradiation means 100 Optical disk.

Claims (6)

A display layer made of a photochromic composition containing a photochromic compound represented by general formula (I) and a compound having a long chain structure represented by general formula (II) is formed on a support substrate,
An image display medium comprising, in the display layer, a first photochromic compound exhibiting a yellow hue in an associated state, a second photochromic compound exhibiting a magenta hue, and a third photochromic compound exhibiting a cyan hue.

(However, R ₁ and R ₂ are independently an alkyl group having 12 or more carbon atoms, an alkanoyloxymethyl group, an alkoxy group, an alkoxycarbonyl group, an alkoxycarbonylalkyl group, a carboxyalkyl group, a hydroxyalkyl group, and an alkylphenyl group. And R _{3 to} R ₁₃ are independently hydrogen or a substituent.)

(However, R ₁₄ and R ₁₅ are independently hydrogen or an alkyl group, X is a structure having hydrogen bonding or associating properties, and a long chain structure having 12 or more carbon atoms as a whole.)   The display layer has a structure in which a display layer including only the first photochromic compound, a display layer including only the second photochromic compound, and a display layer including only the third photochromic compound are stacked. The image display medium according to claim 1.   Rotation driving means for rotationally driving an optical disk having an optical disk label recording surface on which the display layer according to claim 1 is formed, ultraviolet light irradiation means for partially irradiating the optical disk label recording surface with ultraviolet light, An image forming apparatus comprising: heating means for raising a temperature to a predetermined temperature necessary for image stabilization.   A rotation driving means for rotationally driving an optical disc having an optical disc label recording surface on which the display layer according to claim 1 is formed, and an ultraviolet light irradiation for partially irradiating the display layer on the optical disc label recording surface with ultraviolet light. And heating means for raising the temperature of the display layer to a predetermined temperature necessary for image stabilization, and heating means for raising the temperature of the display layer to a predetermined temperature necessary for erasing the formed image. Image forming apparatus.   Rotation driving means for rotationally driving an optical disk having an optical disk label recording surface on which the display layer according to claim 1 is formed, ultraviolet light irradiation means for irradiating the display layer of the optical disk label recording surface with ultraviolet light, Visible light irradiating means for irradiating visible light in a wavelength range corresponding to the maximum absorption wavelength of each photochromic compound in a colored state, and a heating means for raising the display layer to a predetermined temperature necessary for image stabilization An image forming apparatus.   Rotation driving means for rotationally driving an optical disk having an optical disk label recording surface on which the display layer according to claim 1 is formed, ultraviolet light irradiation means for irradiating the display layer of the optical disk label recording surface with ultraviolet light, A visible light irradiating means for irradiating visible light in a wavelength range corresponding to the maximum absorption wavelength of each photochromic compound in a colored state, and a heating means for raising the display layer to a predetermined temperature necessary for image stabilization, were formed. An image forming apparatus comprising: a heating unit that raises the temperature of the display layer to a predetermined temperature necessary for erasing the image.

Images