JP4122832B2 - Rewritable display medium, display device, and display method using the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is a rewritable color display and display erasure by applying heat and a magnetic field to magnetophoresis white magnetic particles dispersed in a plurality of kinds of colored hot-melt organic compounds sealed in a display device. The present invention relates to a display medium, a display device, and a display method using these.
[0002]
[Prior art]
Examples of conventional display devices using electrophoresis and magnetophoresis include various devices disclosed in Japanese Patent Application Laid-Open Nos. 64-86116, 8-54841, and 8-297470. .
Among them, Japanese Patent Application Laid-Open No. 64-86116 discloses an electrophoretic display device that performs a uniform and stable display operation by applying a microcapsule enclosing a dispersion medium and electrophoretic particles.
Japanese Patent Application Laid-Open No. 8-54841 discloses a similar magnetophoretic display device, in particular, a display device capable of performing a clear display with a high recording speed.
Japanese Patent Application Laid-Open No. 8-297470 discloses a magnetophoretic display device having a configuration in which the durability of the microcapsules is enhanced and the back surface is colored in various colors.
[0003]
[Problems to be solved by the invention]
However, the image display panels used in the various electrophoretic display devices and the magnetophoretic display devices as described above are limited to the background color, the characters, and the design colors. It was not possible to achieve full color display that displayed many colors.
[0004]
On the other hand, as a magnetic recording medium capable of performing color display, for example, as described in Japanese Patent Laid-Open No. 1-63991, the N pole and the S pole of the magnetic particles are colored in different colors, and the magnetic force There is known a technique in which color display is performed by rotating magnetic particles by application of.
[0005]
Japanese Laid-Open Patent Publication No. 4-175196 discloses a magnetic recording medium that performs color display by coloring magnetic particles having different magnetic characteristics in different colors and controlling the magnetic field intensity.
[0006]
However, in the magnetic recording medium described in Japanese Patent Application Laid-Open No. 1-63991, a process such as coloring by coloring each fine magnetic particle, or the N pole and S pole of the magnetic particle are different. Since the process of coloring the color is extremely complicated, there is a problem that it is difficult to strictly perform the color coding of each pole.
[0007]
In the magnetic recording medium described in JP-A-4-175196, it is difficult to control the magnetic field strength at the time of display, and it is difficult to display a clear image due to the ambiguity of the magnetic field control. There is a problem that there is.
[0008]
On the other hand, Japanese Patent Application Laid-Open No. 2000-35598 discloses a technique in which electrophoretic particles colored in different colors are enclosed in microcapsules and color display is performed by applying an electric field. There is a problem in that an independent electrode needs to be provided, and the manufacturing cost increases.
[0009]
Accordingly, the present invention provides a display medium, a display device, and a display method using these, which are capable of simultaneous multi-color display, have excellent image stability, are inexpensive, and use full-color magnetophoresis.
[0010]
[Means for Solving the Problems]
In the present invention, there is provided a display medium having a recording layer on a support made of a non-magnetic material, wherein the recording layer has a plurality of minute void members having voids arranged therein, and the inside of the minute void member. Each of the white magnetic particles is dispersed in a heat-fusible organic compound colored in an arbitrary color showing a solid phase at room temperature, The heat-fusible organic compound is colored in any one of a plurality of colors, and the melting point of the heat-fusible organic compound enclosed in the minute gap member distinguished by the color is different for each color Selected to be With a magnetic field applied to the recording layer, The display target location of the recording layer is Of heat-meltable organic compounds plural Melting point One temperature region selected from multiple temperature regions separated by Heated at a temperature according to , By melting any hot-meltable organic compound, dispersed in the molten hot-melt organic compound A rewritable display medium that selectively moves white magnetic particles to display an image is provided.
[0011]
Further, in the present invention, a plurality of minute void members having voids inside are arranged on a support made of a nonmagnetic material, and a recording layer is provided. Inside Each of the white magnetic particles is dispersed in a heat-fusible organic compound colored in an arbitrary color showing a solid state at room temperature. Thus, the melting point of the heat-fusible organic compound enclosed in the microscopic void member distinguished by the color is selected so as to be different for each color. A display medium having a configuration; a magnetic field applying unit that applies a magnetic field to the recording layer of the display medium; and a heating unit that heats the recording layer. Recording layer Display target location The heat-meltable organic compound plural Melting point One temperature region selected from multiple temperature regions separated by Heating at a temperature according to Dispersed in the molten hot-melt organic compound by melting any hot-melt organic compound Provided is a display device for displaying an image by selectively moving white magnetic particles.
[0012]
Further, in the present invention, a microporous member having a recording layer in which a plurality of microvoided members having voids are arranged on a support made of a nonmagnetic material is provided. Inside Each of the white magnetic particles is dispersed in a heat-fusible organic compound colored in an arbitrary color showing a solid state at room temperature. Thus, the melting point of the heat-fusible organic compound enclosed in the microscopic void member distinguished by the color is selected so as to be different for each color. Using a display medium having a configuration, a magnetic field is applied to the recording layer, and the recording layer is Display target location The the above Of heat-meltable organic compounds plural Melting point One temperature region selected from multiple temperature regions separated by Heated at a temperature according to By melting any hot-meltable organic compound Provided is a display method for displaying an image by selectively moving white magnetic particles dispersed in the melted hot-melt organic compound.
[0013]
According to the present invention, a rewritable display medium, display device, and display capable of performing clear color tone, high-resolution full-color display by a simple method, and capable of erasing sharp and clear image display A method can be provided.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, specific embodiments of the present invention will be described with reference to the drawings. However, the reversible multicolor recording medium of the present invention is not limited to the following examples.
[0015]
FIG. 1 shows a schematic sectional view of an example of the display medium of the present invention.
As shown in FIG. 1, the display medium 10 of the present invention has a configuration in which a recording layer 12 and a protective layer 13 are laminated on a support 11. The recording layer 12 has a configuration in which microscopic void members 14 having voids are filled and arranged therein, and the white magnetic particles 20 are in a solid state at room temperature colored in an arbitrary color in the microscopic void member 14. It shall be disperse | distributed to the hot-meltable organic compounds 21-23 shown.
Hereinafter, the display medium 10 of the present invention will be described in detail.
[0016]
The support 11 is formed of a nonmagnetic material, and examples of the forming material include synthetic resins such as polyvinyl chloride, polyester, polycarbonate, polymethyl methacrylate, polystyrene, and polyethylene terephthalate, natural resins, paper, and synthetic paper. , Metals, ceramics or the like can be used alone or in combination.
As for the shape of the support 11, a conventionally known shape such as a card shape, a sheet shape, a film shape and the like can be selected according to the application, and conventionally known physical properties required according to the application, for example, strength, rigidity, It is good also as what added concealment property, light impermeability, etc.
[0017]
The recording layer 12 has a configuration in which minute gap members 14 having gaps inside are filled and arranged.
In the display medium shown in FIG. 1, the microscopic gap members 14 are filled and arranged on the support 11 in a planar shape. However, in consideration of the clearness and resolution of the display image, the microscopic gap members 14 may be stacked. .
The microvoid member 14 is not particularly limited. For example, a microcapsule, a capillary, or a cell that can enclose a dispersion medium can be applied to form a microvoid structure. If it exists, the resolution in the display medium 10 and the display device that are finally obtained can be improved by forming the gap structure more finely, which can be applied to any conventionally known ones.
[0018]
In the minute gap member 14, the first to third heat-meltable organic compounds 21 to 21 which are colored in any color, for example, the three primary colors yellow, magenta, and cyan and exhibit a solid state at room temperature. 23 is enclosed, and white magnetic particles 20 are dispersed in the heat-meltable organic compounds 21 to 23.
The heat-meltable organic compound is not limited to yellow, magenta, and cyan colors, and is selected as an arbitrary color according to the color desired to be displayed on the finally obtained display medium.
[0019]
Examples of the material for forming the white magnetic particles 20 include stainless steel such as iron, nickel, iron / nickel alloy, iron / nickel / chromium alloy, cobalt, cobalt / aluminum alloy, samarium / cobalt alloy, and the like. Can be applied as a core material of the white magnetic particles 20 using a flaky shape using an atomizer or a hammer mill.
[0020]
The white magnetic particles 21 to 23 are made of, for example, TiO as the magnetic core material. ₂ It is formed by coating with an equivalent oxide and a synthetic resin made of polyester or acrylic resin, or by applying various conventionally known dyes. The coloring method is not limited at all, and a conventionally known method can be applied.
The white magnetic particles 20 preferably have a particle diameter of 5 to 30 μm in consideration of easiness of movement by applying magnetism, which will be described later, and image contrast in the display medium 10. As long as the shape of the white magnetic particles 21 to 23 is a shape such as a spherical shape or a needle shape that does not hinder movement by applying a magnetic force, conventionally known various shapes can be applied.
[0021]
The first to third heat-fusible organic compounds 21 to 23 in which the white magnetic particles 20 are dispersed each show a solid state at a normal temperature (about 10 to 30 ° C.) and are heated to a temperature higher than the normal temperature ( For example, natural or synthetic waxes such as paraffin wax and carnauba wax, natural or synthetic resins, carboxylic acid esters, etc. are used alone or in combination as appropriate. be able to. In particular, it is preferable that the change from the solid phase state to the fluid state is steep according to the temperature change.
[0022]
The first to third heat-meltable organic compounds 21 to 23 are colored in different colors, and in this example, the three primary colors yellow, magenta, and cyan are colored as described above. It is assumed that The melting points of the first to third hot-melt organic compounds 21 to 23 distinguished by these colors are selected to be different for each color. For example, the melting point of the first hot-melt organic compound 21 is set to T1. When the melting point of the second heat-meltable organic compound 22 is T2 and the melting point of the third heat-meltable organic compound 23 is T3, a material that satisfies T1>T2> T3 is selected.
[0023]
Specifically, the yellow first heat-fusible organic compound 21 has a melting point of about 90 ° C., the magenta second heat-fusible organic compound 22 has a melting point of about 65 ° C., and the cyan third heat-fusible organic compound 21. As compound 23, paraffin wax having a melting point of about 40 ° C. can be applied.
In addition, melting | fusing point of the 1st-3rd thermomeltable organic compounds 21-23 can be specified to the thing of a suitable range by selecting the number of the hydrocarbon chains in molecular structure, for example.
[0024]
For coloring the first to third hot-melt organic compounds 21 to 23, pigments or dyes can be applied. A pigment can be used alone or a kneaded product with a resin, and an azo dye or a phthalocyanine dye can be applied as a dye. These can be colored by dispersing them in the first to third hot-melt organic compounds 21 to 23 or selecting compatible ones.
[0025]
For example, an acrylic resin, a methacrylic resin, or a polystyrene resin may be used as the microvoid member 14 that is a so-called shell material enclosing the white magnetic particles 20 and the first to third hot-melt organic compounds 21 to 23 described above. In addition, it can be formed of a known resin material such as a polyester resin, a polyurethane resin, a polyurea resin, a polyamide resin, an epoxy resin, or a natural resin, alone or in a mixture of two or more.
[0026]
As the microscopic gap member 14, a microcapsule in which a so-called core substance mainly composed of the above-described white magnetic particles 20 and the first to third hot-melt organic compounds 21 to 23 is encapsulated is preferably used. Examples of the method for producing such microcapsules include the following.
[0027]
For example, a phase separation method in which a concentrated polymer phase is separated around the core material dispersed in the polymer solution, and a liquid-cured coating film in which the polymer is cured around the core material in the polymer solution by a polymer curing test agent or the like. Method, an in-situ polymerization method in which a monomer or a polymerization catalyst is supplied from either the inner phase or the outer phase of the emulsion in which the core material is dispersed and the surface of the core material is covered with a polymer, and the emulsion in which the core material is dispersed A microencapsulation technique such as an interfacial polymerization method in which a monomer is supplied from both an internal phase and an external phase is suitable, but it is not limited to these methods.
[0028]
Among the above methods, microcapsules having a uniform particle diameter and uniformly dispersed white magnetic particles 20 can be manufactured by using in-situ polymerization method or phase separation method. Examples of the polymerizable monomer used in these methods include acrylic acid esters, methacrylic acid esters, styrene and derivatives thereof, isocyanates, various amines, and compounds having an epoxy group.
[0029]
The recording layer 12 can be formed by dispersing the fine gap member 14 made of, for example, microcapsules as described above in a predetermined binder and coating the dispersion on the support 11. As the binder, for example, a water-based binder, a solvent-based binder, an emulsion-based binder, and the like can be applied.
[0030]
Specifically, the recording layer 12 includes a conventionally known printing method such as an offset printing method, a gravure printing method, and a silk screen printing method, a coating method such as a roll coating method and a knife edge method, and a micro gap member 14 such as the microcapsule. A transfer method using a transfer sheet mixed with the above, an ink jet method in which ink containing the above-described microcapsules or the like is sprayed on the support 11, and the above-described microcapsules or the like mixed between the support 11 and a protective layer 13 described later. It can be produced by various methods such as a method of filling a solution, and can be appropriately selected according to the intended use and quantity of the display medium 10.
[0031]
Next, the protective layer 13 will be described.
Examples of the material for forming the protective layer 13 include epoxy resins, tetrafluoroethylene, polyvinyl chloride, polyester, polycarbonate, polymethyl methacrylate, polystyrene, polyethylene terephthalate, and other synthetic resins, natural resins, and the like.
The protective layer 13 holds the recording layer 12 formed on the support 11 and has light permeability so that the white magnetic particles 20 enclosed in the microscopic gap member 14 can be visually recognized from the outside. Is necessary.
In order to maintain the mechanical strength of the display surface as the display medium 10, a necessary film thickness is appropriately selected and formed.
[0032]
Next, a display device that forms an image on the above-described display medium 10 of the present invention and an image display method using these will be described.
FIG. 2 shows a schematic configuration diagram of an example of the display device of the present invention.
The display device 30 of the present invention includes the display medium 10 shown in FIG. 1, a magnetic field applying unit 31 that applies a magnetic field, and a heating unit 32.
The magnetic field application unit 31 has a function of applying a magnetic field to the white magnetic particles 20 of the recording layer 12, and the heating unit 32 applies the first to third heat-meltable organic compounds 21 to 23 of the recording layer 12. In contrast, it has a function of heating.
2 shows a state in which the magnetic field applying unit 31 and the heating unit 32 are arranged on the side of the display medium 10 facing the protective layer 13, but these are the sides independently facing the support 11 respectively. It is also possible to arrange them in an appropriate manner according to the display color of image formation to be described later.
[0033]
Next, a method for displaying an image using the display medium 10 and the display device 30 of the present invention described above will be described.
In this example, three primary colors are displayed on the display medium 10 shown in FIG. 1, the first hot-melt organic compound 21 is yellow, the second hot-melt organic compound 22 is magenta, and the third heat As the fusible organic compound 23, cyan colored ones were applied.
[0034]
As described above, the first to third hot-melt organic compounds 21 to 23 colored yellow, magenta, and cyan are encapsulated in different microscopic gap members 14, and are distinguished by these colors. The melting points of the heat-fusible organic compounds 21 to 23 enclosed in the microscopic void member 14 are selected so as to be different for each color, and the melting point of the first heat-fusible organic compound 21 is T1 and the second melting point. When the melting point of the hot-melt organic compound 22 is T2, and the melting point of the third hot-melt organic compound 23 is T3, T1>T2> T3.
[0035]
Next, a specific display method will be described.
First, in the state shown in FIG. 2, all of the white magnetic particles 20 encapsulated in the three kinds of minute gap members 14 are on the protective layer 13 side, that is, the display surface side, and all the minute gap members 14 perform white display. Therefore, white display (erasure state) is made on the entire surface.
[0036]
When displaying yellow, first, as shown in FIG. 3, the heating means 32 is heated to a temperature (t> T1) higher than the melting point T1 of the first heat-meltable organic compound 21, and all the minute amounts are displayed. The hot-melt organic compounds 21 to 23 in the gap member 14 are melted. Then, the magnetic field applying means 31 is disposed on the support 11 side, that is, the side opposite to the display surface side, and a magnetic field is applied to cause the white magnetic particles 20 to undergo magnetophoresis. If it does in this way, all the white magnetic particles 20 will move to the support body 11 side, and all the colors of the colored 1st-3rd heat-meltable organic compounds 21-23 will be visually recognized from the display surface side. Then, a black display is made on the entire surface.
Next, as shown in FIG. 4, by the heating means 32, the temperature is lower than the melting point T1 of the first hot-melt organic compound 21 and higher than the melting point T2 of the second hot-melt organic compound 22 (T1> t > T2), only the first heat-meltable organic compound 21 is solidified, and the second and third heat-meltable organic compounds 22 and 23 are dissolved. Then, the magnetic field applying means 31 is arranged on the protective layer 13 side, that is, on the display surface side, and a magnetic field is applied, and the white magnetic particles 20 dispersed in the second and third hot-melt organic compounds 22 and 23 are protected. Run to the side.
In this way, the white magnetic particles 20 dispersed in the second and third heat-meltable organic compounds 22 and 23 are fixed on the display surface side, and the first heat-meltable organic compound 21 colored yellow. Since only the color of can be visually recognized, yellow can be displayed on the display surface.
[0037]
Next, a case where magenta display is performed will be described.
First, as shown in FIG. 2, a white display (erased state) is formed on the entire surface. Next, as shown in FIG. 5, the heating means 32 causes the temperature (T1> t) to be lower than the melting point T1 of the first hot-melt organic compound 21 and higher than the melting point T2 of the second hot-melt organic compound 22. > T2), and the second and third hot-melt organic compounds 22 and 23 are dissolved. Then, the magnetic field applying means 31 is disposed on the support 11 side, that is, the side opposite to the display surface side, and a magnetic field is applied, and the white magnetic particles 20 dispersed in the second and third heat-fusible organic compounds 22 and 23 are dispersed. Migration to the support 11 side. As a result, only the white magnetic particles 20 dispersed in the first heat-meltable organic compound 21 are fixed on the display surface side as shown in FIG. A mixed color display of magenta and cyan, which are the colors of the compounds 22 and 23, is achieved.
Next, as shown in FIG. 6, a temperature lower than the melting point T2 of the second hot-melt organic compound 22 and higher than the melting point T3 of the third hot-melt organic compound 23 by the heating means 32 (T2>t>). At T3), the first hot-melt organic compound 21 and the second hot-melt organic compound 22 are solidified and only the third hot-melt organic compound 23 is dissolved.
Then, the magnetic field applying means 31 is arranged on the protective layer 13 side, that is, the display surface side, a magnetic field is applied, and the white magnetic particles 20 dispersed in the third hot-melt organic compound 23 are migrated to the protective layer 3 side. In this way, since the white magnetic particles 20 dispersed in the first and third heat-meltable organic compounds 21 and 23 are fixed on the display surface, the color of the second heat-meltable organic compound 22 is changed. A certain magenta can be displayed.
[0038]
Next, a case where cyan display is performed will be described.
First, as shown in FIG. 2, a white display (erased state) is formed on the entire surface.
Next, as shown in FIG. 7, a temperature (T2>t> lower than the melting point T2 of the second hot-melt organic compound 22 and higher than the melting point T3 of the third hot-melt organic compound 23 by the heating means 32. At T3), the first hot-melt organic compound 21 and the second hot-melt organic compound 22 are solidified and only the third hot-melt organic compound 23 is dissolved.
Then, the magnetic field applying means 31 is arranged on the support 11 side, that is, the side opposite to the display surface side, and a magnetic field is applied, and the white magnetic particles 20 dispersed in the third heat-fusible organic compound 23 are placed on the support 11 side. Run. In this way, as shown in FIG. 7, only the white magnetic particles 20 dispersed in the third heat-fusible organic compound 23 colored in cyan are fixed on the support 11 side. In addition, cyan, which is the color of the third heat-meltable organic compound 23, can be displayed.
[0039]
As described above, in the display medium 10 and the display device 30 of the present invention, a magnetic field is applied and heated at a temperature corresponding to the melting point of each of the first to third hot-melt organic compounds 21 to 23, By selectively melting these heat-meltable organic compounds and selectively moving the white magnetic particles 20 dispersed in the melted heat-meltable organic compound, the desired colors or combinations of three primary colors are finally obtained. It is possible to display intermediate colors by erasing or to erase these displays.
[0040]
Specifically, the display medium 10 and the display device 30 of the present invention include various cards such as a point card, a medical examination ticket, a commuter pass, a recording bulletin board, an advertising board, a memo board, a blackboard, a white board, a portable memo pad, and an infant. It can be applied to toys, educational materials, calligraphy boards, display boards for various game machines, and the like.
[0041]
Next, the display medium, the display device, and the display method using these according to the present invention will be described with reference to specific examples, but the present invention is not limited to the following examples.
[0042]
〔Example〕
(Preparation of display medium)
First, a microcapsule in which a hot-melt organic compound colored yellow is encapsulated is prepared.
5 parts by weight of white colored magnetic fine particles containing 70% Fe as a main component are uniformly dispersed in 6 parts by weight of paraffin wax having a melting point of 90 ° C., which is colored yellow and heated to 100 ° C. Was dispersed in 200 parts by weight of a 10% gelatin aqueous solution heated to 95 ° C. using a homogenizer at a rotational speed of 2000 rpm until the average particle size became 75 μm for about 5 minutes.
To the dispersion obtained as described above, 200 parts by weight of a 10% aqueous gum arabic solution was added, and further 1000 parts by weight of water was added and maintained at 40 ° C., and a 10% aqueous acetic acid solution was added dropwise to adjust the pH to 4. It adjusted so that it might become. Thereafter, the liquid temperature was cooled to 7 ° C., 10 parts by weight of 30% formalin aqueous solution was added, 10% aqueous sodium hydroxide solution was added dropwise to adjust the pH to 9, and gelatin and gum arabic shell microcapsules A Was made.
[0043]
In place of the yellow-colored paraffin wax having a melting point of 90 ° C., a magenta-colored paraffin wax having a melting point of 65 ° C. is applied. A microcapsule B encapsulating the compound was prepared.
[0044]
Instead of the yellow-colored paraffin wax having a melting point of 90 ° C., a cyan-colored paraffin wax having a melting point of 40 ° C. is applied, and the heat-fusible organic colored cyan is performed by the same process as described above. A microcapsule C encapsulating the compound was prepared.
[0045]
Next, a coating liquid in which the microcapsules A, B, and C produced as described above are uniformly dispersed in an aqueous polyvinyl alcohol solution is applied onto a transparent polyethylene terephthalate film (support) having a thickness of 30 μm, and a recording layer is formed. Formed.
Further, a protective layer having a thickness of 3 μm was formed on the recording layer using an acrylic resin, and the intended display medium 10 of the present invention was produced.
[0046]
(Display is cleared)
A magnetic field was applied to the entire surface of the display medium manufactured as described above from the protective layer side, that is, the display surface side, and the entire surface was heated at 95 ° C. By doing so, the paraffin wax in all the microcapsules was melted, and each white magnetic particle was transferred to the display surface side by magnetophoresis.
As a result, only the color of the white magnetic particles can be visually recognized from the display surface side. By stopping heating and magnetic field application in this state, the paraffin wax is solidified and the display medium 10 in the erased state (white) is obtained. It is done.
[0047]
(Displays black)
A magnetic field is applied to the entire surface of the display medium manufactured as described above from the support side, that is, the side opposite to the display surface, and only a place where display is desired is selectively performed at 90 ° C. or higher by a heating means such as a thermal head or a laser. Heat to temperature.
At this time, the paraffin wax in all the microcapsules at the heated location was melted, and each white magnetic particle moved to the side opposite to the display surface by magnetophoresis.
This makes it possible to visually recognize the colors of yellow, magenta, and cyan heat-meltable organic compounds from the display surface side. By stopping heating and magnetic field application in this state, the paraffin wax is solidified and visually. A display medium 10 displayed in black is obtained.
[0048]
(Displays yellow)
A magnetic field is applied to the entire surface of the display medium manufactured as described above from the support side, that is, the side opposite to the display surface side, and only a place where display is desired is selectively performed by a heating means such as a thermal head or a laser at 90 ° C. or higher. Heat to the temperature of. At this time, the paraffin wax in all the microcapsules at the heated location was melted, and each white magnetic particle was transferred to the support side by magnetophoresis.
Next, the magnetic field applying means was arranged on the display surface side, and only the place where the display was desired was selectively adjusted to a temperature of 65 ° C. or higher and 90 ° C. or lower by the heating means. As a result, only the paraffin wax colored magenta and cyan was in a melted state, and the white magnetic particles dispersed in the paraffin wax of magenta and cyan were transferred to the display surface side by magnetophoresis.
By stopping the heating and magnetic field application in this state, the paraffin wax is solidified and the display medium 10 visually displayed in yellow is obtained.
[0049]
(Displays magenta)
The display medium manufactured as described above is first set in an erased state (white display). Next, the magnetic field applying means is arranged on the support side, that is, the side opposite to the display surface to apply the magnetic field, and only the place where display is desired is selectively performed at a temperature of 65 ° C. or higher and 90 ° C. or lower by heating means such as a thermal head or laser. Heat to temperature. As a result, only the paraffin wax colored magenta and cyan was melted, and each white magnetic particle dispersed in the paraffin wax of magenta and cyan was transferred to the support side by magnetophoresis.
Next, the magnetic field applying means was arranged on the display surface side, and only the place where display was desired was selectively adjusted to a temperature of 40 ° C. or higher and 65 ° C. or lower by a heating means such as a thermal head or a laser, and magnetic field was applied. As a result, only the paraffin wax colored cyan was melted, and the white magnetic particles dispersed in the cyan paraffin wax moved to the display surface side by magnetophoresis.
By stopping heating and magnetic field application in this state, the paraffin wax is solidified, and the display medium 10 visually displayed on magenta is obtained.
[0050]
(Displays cyan)
The display medium manufactured as described above is first set in an erased state (white display).
The magnetic field applying means is arranged on the support side, that is, on the opposite side of the display surface to apply the magnetic field, and only the place where the display is desired is selectively heated to a temperature of 40 ° C. or higher and 65 ° C. or lower by a heating means such as a thermal head or laser Heat. As a result, only the paraffin wax colored cyan was melted, and the white magnetic particles dispersed in the cyan paraffin wax moved to the support side by magnetophoresis.
By stopping heating and magnetic field application in this state, the paraffin wax is solidified, and the display medium 10 visually displayed on magenta is obtained.
[0051]
(Displays neutral colors)
By combining the display of yellow, magenta and cyan as described above, an arbitrary intermediate color can be displayed, and a full color image can also be displayed.
[0052]
According to the above-described image display mechanism using the display medium and the display device of the present invention, the size of the microvoid member such as the microcapsule enclosing the heat-fusible organic compound of each color, and the thermal for applying heat treatment thereto. By controlling the resolution of the heating means such as the head, the resolution of the display medium can be improved.
[0053]
In the example of the image display described above, the case where the color of the heat-fusible organic compound sealed in the minute gap member 14 of the display medium 10 in FIG. 1 is yellow, magenta, or cyan has been described. However, the present invention is not limited to this example, and a heat-meltable organic compound of any color can be selected according to the color desired to be displayed on the finally obtained display screen.
[0054]
【The invention's effect】
According to the present invention, in a state where a magnetic field is applied, the heat-fusible organic compound enclosed in the microscopic gap member constituting the recording layer is selectively melted by heating means such as a thermal head, and this heat melting is performed. By selectively moving the white magnetic particles dispersed in the organic compound, the color tone is clear, high-resolution full-color display can be performed, and sharp and clear image display can be erased. It was possible to provide a rewritable display medium, a display device, and a display method.
[0055]
In particular, in the present invention, by applying a heat-fusible organic compound having a different melting point for each color, it is possible to display an image for each color only by controlling the heating temperature, and there is no color mixing and clearness. Color image display is now possible.
[0056]
Moreover, by applying white particles as magnetic particles dispersed in the heat-meltable organic compound, it is possible to obtain contrast with each color, high resolution, and clearer image display.
[0057]
In addition, according to the display medium and the display device of the present invention, it is possible to easily display an image by combining heating at a relatively low temperature enough to melt the heat-fusible organic compound and magnetic application. As a result, it is possible to display a clear image with very little energy consumption.
[0058]
Further, according to the display medium and the display device of the present invention, the white magnetic particles are dispersed in the dispersion medium made of a heat-fusible organic compound that shows a solid phase at room temperature in the minute gap member, and are fixed except during recording and erasing. Therefore, even when magnetism was applied from the outside after information recording, the white magnetic particles did not move, and an extremely stable recording state could be obtained.
[0059]
In the display medium, the display device, and the display method of the present invention, the white magnetic particles dispersed in the heat-fusible organic compound melted by the operation of the heating means are moved by magnetic application to form and erase an image. Therefore, an extremely fine image can be formed by increasing the operation accuracy of the heating means.
[0060]
In addition, since the recording layer constituting the display medium of the present invention can be formed by applying a coating liquid containing a minute gap member on a support, it can be produced by a very simple manufacturing process, And it was possible to manufacture at an extremely low cost.
[Brief description of the drawings]
FIG. 1 shows a schematic cross-sectional view of a display medium of the present invention.
FIG. 2 is a schematic sectional view of the display device of the present invention.
FIG. 3 is a state diagram for performing image formation in the display medium and the display device of the present invention.
FIG. 4 is a state diagram for performing image formation in the display medium and the display device of the present invention.
FIG. 5 shows a state diagram for performing image formation in the display medium and display device of the present invention.
FIG. 6 is a state diagram for performing image formation in the display medium and the display device of the present invention.
FIG. 7 shows a state diagram for performing image formation in the display medium and display device of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Display medium, 11 ... Support substrate, 12 ... Recording layer, 13 ... Protective layer, 14 ... Micro gap member, 20 ... White magnetic particle, 21 ... 1st heat-meltable organic compound, 22... 2nd heat-meltable organic compound, 23... 3rd heat-meltable organic compound, 30... Display device, 31.

Claims (9)

A display medium having a recording layer on a support made of a nonmagnetic material,
In the recording layer, a plurality of minute void members having voids inside are arranged,
In the inside of the microscopic void member, each white magnetic particle is dispersed in a heat-fusible organic compound colored in an arbitrary color showing a solid state at room temperature,
The heat-fusible organic compound is colored in any one of a plurality of colors, and the melting point of the heat-fusible organic compound enclosed in the minute gap member distinguished by the color is different for each color Selected to be
A temperature corresponding to one temperature region selected from a plurality of temperature regions divided by a plurality of melting points of the heat-fusible organic compound with a magnetic field applied to the recording layer. Rewriting, characterized in that the image is displayed by selectively moving the white magnetic particles dispersed in the molten heat-fusible organic compound by heating at a temperature and melting any heat-fusible organic compound Possible display medium.   2. The rewritable display medium according to claim 1, wherein the microscopic gap members constituting the recording layer are filled and arranged in a planar shape on the support. The heat-fusible organic compound, rewritable display medium according to claim 1 or claim 2, wherein the ing is colored in any one of the three primary colors.   The rewritable display medium according to any one of claims 1 to 3, wherein the melting point of the heat-meltable organic compound exhibiting a solid phase at normal temperature is 35 ° C or higher and 120 ° C or lower. . On a support made of a nonmagnetic material, there is a recording layer in which a plurality of minute void members having voids arranged therein, and white magnetic particles are in a solid state at room temperature inside the minute void members, respectively. Ri Na are dispersed in heat-fusible organic compound which is colored in any color that indicates the melting point of the heat-fusible organic compound enclosed in the small air gap member are distinguished by the colors, different for each color A display medium configured to be selected , and
Magnetic field applying means for applying a magnetic field to the recording layer;
Heating means for heating the recording layer,
In the state where a magnetic field is applied to the recording layer by the magnetic field applying means, the display target location of the recording layer is selected from a plurality of temperature regions separated by a plurality of melting points of the heat-fusible organic compound by the heating means. The white magnetic particles dispersed in the molten heat-fusible organic compound are selectively moved by heating at a temperature corresponding to the one temperature range to be melted. A display device that performs image display.   6. The display device according to claim 5, wherein the minute gap members constituting the recording layer are filled and arranged in a planar shape on the support. The heat-fusible organic compound, the display device according to claim 5 or claim 6, wherein the ing is colored in any one of the three primary colors.   8. The display device according to claim 5, wherein a melting point of the hot-melt organic compound is 35 ° C. or more and 120 ° C. or less. The recording layer has a recording layer on a support made of a non-magnetic material, and the recording layer has a plurality of microscopic void members arranged therein, and white magnetic particles are formed in the microscopic void member. but Ri Na are dispersed in heat-fusible organic compound which is colored in any color that indicates the solid state at normal temperature, is distinguished by the color sealed in the microvoids in the member of the heat-fusible organic compound Using a display medium configured to have a melting point that is different for each color ,
A magnetic field is applied to the recording layer, and a display target location of the recording layer is heated at a temperature corresponding to one temperature region selected from a plurality of temperature regions separated by a plurality of melting points of the hot-melt organic compound. Then, by melting an arbitrary heat-meltable organic compound, the white magnetic particles dispersed in the molten heat-meltable organic compound are selectively moved to perform image display.

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