JPH07261684A - Display for magnetic display and magnetic display device - Google Patents

Abstract

PURPOSE:To provide a display for magnetic display which is distinct in bright ness and darkness varying in the parts impressed with magnetism and parts not impressed with the magnetism, has high resolution, is bright, has excellent stability of images and is capable of making reversible display, and a magnetic display device. CONSTITUTION:This display 1 for magnetic display has a magnetic display layer 12 contg. microcapsules 15 including dispersion media 24 dispersed with magnetic powder 22 and exhibiting a solid phase state at ordinary temp. This magnetic display device has the display 1 for magnetic display and a thermo- magnetic head driving section consisting of a thermo-magnetic head device for recording and erasing. The display is scanned from the front surface side at the time of recording. The entire surface is heated and the magnetism is impressed over the entire surface from the rear surface or the rear surface is partially scanned at the time of erasing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic display for displaying an image by magnetism upon heating and a magnetic display device using the same, and particularly to a magnetic display capable of reversible display excellent in resolution and image stability. The present invention relates to a display and a magnetic display device using the same.

[0002]

2. Description of the Related Art Conventionally, as a display utilizing magnetism, a magnetic field is applied to a suspension in which magnetic particles are dispersed in a coloring dispersion medium, as described in, for example, JP-A-48-56393. A method is known in which the magnetic particles are moved to change the color of the colored dispersion medium and display is performed.

However, in such a display, when a suspension is sealed between two substrates and a magnetic pen is used to draw characters and a pattern from one substrate to apply magnetism, magnetic particles of the suspension are attracted, Although the characters and patterns can be obtained as they are, since the specific gravity of the magnetic particles is much larger than that of the dispersion medium, the attracted magnetic particles have a drawback that the characters and patterns cannot be retained for a long time because they settle out with time.

Further, since all the magnetic particles magnetized by the magnetic pen are attracted to the magnetic pen, the magnetic particles existing apart from the magnetic pen are also attracted, so that only unclear characters and patterns are obtained. It also had drawbacks. In order to prevent sedimentation of magnetic particles, for example, if the magnetic particles are made finer or the magnetic particles are coated with a polymer having a low specific gravity, and the apparent specific gravity of the magnetic particles approximates that of the dispersion medium, the magnetic particles Since the force becomes extremely small, it becomes difficult to be sucked by the magnetic pen, which causes a defect that it is not possible to obtain a clear character or pattern with high density.

Further, if the apparent specific gravity of the magnetic particles is approximated to that of the dispersion medium, the magnetic particles are difficult to be attracted to the opposite side of the substrate even when characters and patterns are erased, and the particles cannot be completely erased. Repeatedly, it turned black overall, which was not practical.

As a mode for solving these drawbacks, for example, Japanese Patent Publication No. 57-27463 and Japanese Patent Laid-Open No. 62-53.
As described in Japanese Patent No. 359, as a dispersion medium,
By using a liquid that has a yield value of a certain value or more, or by using a thickener, clear and high-contrast characters and images without blur can be displayed, and the display can be kept stable for a long time, and erasure can be completed completely. There are known displays that can be used beautifully.

However, this display is formed by forming a honeycomb-shaped cell having a side and a depth of about 2 mm on the entire surface of a transparent plastic sheet, and magnetic particles and a white pigment are dispersed in the cell. The suspension dispersed in a medium was injected, and the suspension was sealed with a transparent sheet, which had the following drawbacks. That is, since the image is formed by moving the magnetic particles from the back surface to the front surface in the honeycomb-shaped cell, it is impossible to make the resolution of the image smaller than that of the honeycomb-shaped cell. Further, it is difficult to form the honeycomb-shaped cells, increase the size of the honeycomb-shaped cells, or make the honeycomb-shaped cells very small, and the process of injecting the suspension into the honeycomb-shaped cells.

As another mode, for example, Japanese Patent Laid-Open No. 1-14
5637 or Eyne S. et al. Trumb
le P.L. S. & E. No. 7 213 (1963), unlike a display in which magnetic particles and a pigment are sealed in a honeycomb-shaped cell as described above, the magnetic particles are encapsulated in microcapsules and coated on a support. Display is known. According to this method
By controlling the particle size of the microcapsules, the resolution can be increased and the manufacturing process is easy. Also,
Various films and the like can be selected as the substrate on which the microcapsules are applied, and the shape and size can be freely selected.

However, in the image forming method shown here, first, at the time of manufacturing a display, the magnetic particles in the coated capsules are orientated in advance in parallel with the plane of the display so that all the incident light is reflected to make it appear bright. Next, by magnetically recording, the magnetic particles rotate to scatter and absorb the incident light, and a contrast is produced, so that a black image is formed. That is, the magnetic particles used here are generally limited to flat particles such as nickel, iron and barium-ferrite, and since the principle of image formation is based on the orientation of the magnetic particles, it is It is necessary to always orient the flat surface in parallel with the plane of the magnetic recording medium, but it is difficult to orient it uniformly and in a certain direction in this way. The result is an unclear image of light and dark.

Further, as another mode using the microcapsules, for example, Japanese Patent Laid-Open No. 2-146082,
As described in JP-A-4-233581, a display in which light-absorbing magnetic particles and light-reflecting non-magnetic particles are enclosed in microcapsules is known.

In the image formation of this form, first, the permanent magnet attracts the light-absorbing magnetic particles in the microcapsules to the back surface side of the display, and accordingly, the light-reflecting non-magnetic particles remain on the surface of the display. By doing so, the surface becomes the color of the non-magnetic particles and the erased state is achieved. Next, apply magnetism from the display surface with a permanent magnet.
By recording, the light absorbing magnetic particles are attracted to the surface by magnetism, and desired characters and images are formed.

However, since the display thus obtained has a wide range of magnetic force, its resolution is very inferior to that of recording by other heat or light. Furthermore, since the above-mentioned display can be easily printed and erased by magnetic force, the stability of the image may be caused by fogging the unprinted part or erasing the image just by touching the magnet. Has the disadvantage of being bad.

[0013]

From the above, the conventional display using a magnetic material as a display means cannot display a high resolution image, and a partial display of an image displayed due to the influence of external magnetism. Or because the image is erased or fog occurs in the unprinted part in an unreadable state,
Stable recording could not be performed. Further, there has not been a display having the mobility of the magnetic particles contained therein, that is, both the good recording reactivity and the recorded image stability. In view of the above, the present invention provides a reversible display capable of reversible display, in which a portion to which magnetism is applied has a bright and dark distinction from a portion to which no magnetism is applied, has high resolution, is clear, and has excellent image stability. An object is to provide a magnetic display device.

[0014]

The present invention has been made to achieve the above object, and the invention according to claim 1 is one in which at least one is made of a nonmagnetic material having transparency. In addition, a magnetic display layer is formed in which a microcapsule containing at least magnetic particles and a dispersion medium which is dispersed and shows a solid state at room temperature is dispersedly arranged in a binder. Display.

The invention of claim 2 is the display for magnetic display according to claim 1, characterized in that a colored layer having transparency is laminated on the magnetic display layer.

According to a third aspect of the present invention, in the magnetic display according to the first aspect, the average particle size of the magnetic particles is between 0.1 μm and 10 μm.

According to a fourth aspect of the present invention, in the magnetic display according to the first aspect, the magnetic particles are colored magnetic particles.

According to a fifth aspect of the invention, in the magnetic display according to the first aspect, the dispersion medium is an organic compound having a melting point of 35 ° C. or higher and 80 ° C. or lower.

According to a sixth aspect of the present invention, in the magnetic display according to the first aspect, the average particle size of the microcapsules is between 10 μm and 1000 μm.

According to a seventh aspect of the present invention, at least one magnetic particle and a dispersion medium having a solid state at room temperature, which is formed by dispersing these particles, are included between the supports, at least one of which is a transparent non-magnetic material. Magnetic display in which a magnetic display layer is formed by dispersing microcapsules in a binder, and magnetic particles in the microcapsules disposed on the display surface side of the magnetic display by heating and magnetic application. A heating magnetism generating means for partially attracting and moving the magnetism, and a heating magnetism generating means disposed on the back surface side of the magnetic display for attracting and moving the magnetic particles in the microcapsules by heating and magnetic application, A magnetic display device characterized in that magnetic particles in microcapsules are unevenly distributed on one surface.

[0021]

The magnetic display and the magnetic display device of the present invention have a magnetic display layer containing microcapsules in which magnetic particles are dispersed and which contain a dispersion medium exhibiting a solid state at room temperature. The magnetic particles are attracted to the back side, which is one side of the magnetic display, that is, below the microcapsules, and the surface of the magnetic display that is the other side is the color of the dispersion medium or the difference in the refractive index thereof. Since the color of the magnetic particles is hidden by the light scattering due to, the color tone becomes uniform.

Further, in recording on the magnetic display and the magnetic display device of the present invention, scanning is performed from the surface side of the magnetic display by magnetic generation means having a heating means, and the viscosity is lowered by heat to be in a fluidized state. The magnetic particles in the dispersion medium portion are magnetically moved to the upper side of the microcapsule, that is, to the surface on the side of the magnetic generation means, and an image is formed by the magnetic particles. By applying magnetism to the entire surface from the back surface or scanning the back surface with a magnetism generating means having a heating means, the magnetic particles are attracted to the magnetism generating means side below the microcapsules, and the surface of the magnetic display is A uniform tone is obtained again and the image is erased.

[0023]

The present invention will be described in detail below with reference to the drawings. 1 is a sectional view showing an embodiment of the present invention, FIG. 2 is a sectional view showing another embodiment of the present invention, and FIG.
FIG. 4 is a sectional view showing an example of microcapsules used in the magnetic display layer of the present invention, and FIG. 4 is a sectional view showing an example of colored magnetic particles coated with the colored coating layer of the present invention. FIG. 5 is a sectional view showing an example of the colored magnetic particles coated with the colored coating layer and the hiding layer of the present invention,
FIG. 6 is an explanatory diagram showing a state of the magnetic display according to the present invention during manufacturing, and FIG. 7 is an explanatory diagram showing an unrecorded state due to an erasing operation of the magnetic display according to the present invention. 8 is an explanatory diagram showing a state of the magnetic display of the present invention during recording, FIG. 9 is a conceptual diagram illustrating the magnetic display device of the present invention, and FIG. 10 is a magnetic display device of the present invention. FIG. 12 is an explanatory diagram for explaining the configuration of the recording thermal / magnetic head drive unit, and FIG. 11 is an explanatory diagram for explaining the configuration of the erasing thermal / magnetic head drive unit of the magnetic display device of the present invention.

FIG. 1 shows the structure of the magnetic display 1 of the present invention, in which a support 11 and a magnetic display layer 12 coated with a coating material in which microcapsules 15 containing magnetic particles are dispersed in a binder 16, The protective support 14 is sequentially laminated.

FIG. 2 shows the structure of a magnetic display 10 according to another embodiment of the present invention, which is a support 1
1. A magnetic display layer 1 coated with a coating material in which microcapsules 14 containing magnetic particles are dispersed in a binder 15.
2. A transparent colored layer 13 and a protective support 14 are sequentially laminated.

Further, FIG. 3 is a sectional view showing an embodiment of the microcapsules 15 used in the magnetic display layer 12 in the present invention. The microcapsules 15 are dispersion media (for example, wax) in which the magnetic particles 22 are in a solid state at room temperature.
The core material 21 mainly composed of suspensions dispersed in 24 is encapsulated by a shell material 27 made of a polymer.

As the magnetic particles 22, it is possible to use magnetic particles alone, a mixture of several kinds of magnetic particles, or a mixture of magnetic particles and a polymer. For example, magnetite, ferrite and other iron, cobalt,
A metal exhibiting ferromagnetism such as nickel, an alloy containing these elements, or fine particles of a compound is used. In this case, the magnetic particles may be subjected to surface hydrophobizing treatment such as silane coupling treatment in order to enhance affinity with wax or the like. When a mixture of magnetic particles and a polymer is used, the above-mentioned magnetic particles and a polymer are kneaded and then pulverized, or a monomer in which the magnetic particles are dispersed is subjected to a method such as emulsion polymerization, suspension polymerization, or dispersion polymerization. A method such as polymerization is used. In this case, the polymer is preferably crosslinkable. The size of the magnetic particles is 0.1 μm in consideration of the ease of movement due to magnetism and the image density.
It is preferably between 1 and 10 μm.

The color of the magnetic particles 22 is light or dark brown,
When the color other than the color unique to the magnetic material such as dark brown is used, the magnetic particles are kneaded with a pigment or a dye and a binder, or as shown in FIG. It is possible to use the colored magnetic particles 23 in which the colored coating layer 25 is formed by using a mixture, or a mixture of a pigment and a polymer. As the coloring coating layer 25, for example, fine particles of commonly known inorganic pigments such as titanium dioxide, zinc sulfide, lead titanate, zirconium oxide, lead white, cadmium red, and cadmium yellow, and organic pigments such as phthalocyanine pigments are used. . The coloring coating layer 25 is prepared by a phase separation method in which a concentrated phase of the polymer in which the pigment is dispersed is separated around the magnetic particles 21 dispersed in the polymer solution in which the pigment is dispersed, and in a polymer solution in which the pigment is dispersed. A liquid curing coating method in which a polymer is cured around a dispersed magnetic particle 21 with a curing agent such as a polymer curing test agent, and a suspension of magnetic particles 21 is supplied with a monomer or a polymerization catalyst in which a pigment is dispersed to supply magnetic particles. 22 is a dispersion polymerization method in which the surface of the magnetic particles is covered with a polymer in which a pigment is dispersed, an air current impact method in which the surface of magnetic particles is directly mixed and ground with a pigment, or a suspension in which magnetic particles are dispersed in a polymer solution in which a pigment is dispersed is sprayed. A microencapsulation technique such as a spray drying method of drying by drying is preferable. Another method is to form a pigment layer composed of a metal oxide by immersing magnetic particles in an organometallic compound solution, pulling it up and drying it, and then firing it to decompose the organometallic compound, or diluting a metal salt. Examples include a method in which magnetic particles are suspended in an acidic solution, a metal salt is hydrolyzed to precipitate a hydrated metal oxide on the surface thereof, and the pigment is baked to form a pigment layer made of a metal compound. The method of adjusting the colored layer 25 is not limited to these methods.

Further, as shown in FIG. 5, colored magnetic particles 23 '
A concealing layer 26 may be further provided below the colored coating layer 25. According to this, since the color of the magnetic particles is hidden,
As compared with the case where the colored coating layer 25 formed on the outer shell is formed alone, the colored layer 25 can be made thinner without being affected by the color of the magnetic particles being seen through. The hiding layer 26 is formed of an inorganic powder or a metal thin film dispersed in an organic polymer.

The concealing layer 26 is the colored layer 25 as described above.
It is possible to reduce the effect that the color of the magnetic particles can be seen through, and it is particularly effective when the colored layer is a light color such as yellow. Specifically, it is composed of an inorganic polymer dispersed in an organic polymer or a metal thin film. The adjustment method is a phase separation method in which the concentrated phase of the polymer solution in which the inorganic powder is dispersed is separated around the magnetic particles formed by dispersing the inorganic powder in the polymer solution, and the magnetic property in which the pigment is dispersed in the polymer solution is separated. A liquid curing coating method in which a polymer is cured around a particle 21 with a curing agent such as a polymer curing test agent, a suspension of the magnetic particles 21 in which a monomer in which a pigment is dispersed and a polymerization catalyst are supplied to clean the surface of the magnetic particles 21. Dispersion polymerization method in which the pigment is dispersed in a polymer, magnetic particle surface is directly mixed and milled with the pigment in an air stream, or a suspension in which magnetic particles are dispersed in a polymer solution in which a pigment is dispersed is sprayed and dried. Microencapsulation techniques such as the drying method are preferred. The adjustment method is not limited to these methods. The above-mentioned inorganic powder preferably has a high refractive index and a large hiding power, and for example, titanium dioxide, zinc sulfide, lead titanate, zirconium oxide and the like are preferable, but the inorganic powder is not particularly limited thereto. The method for adjusting the concealing layer 26 using a metal thin film is mainly a method using electroless plating,
There is a method of decomposing the organometallic compound after chemically or physically adsorbing the organometallic compound on the surface of the magnetic particles.
It is preferable that the metal used has almost no magnetic properties and does not affect the color tone of the colored layer, such as aluminum, silver, zinc or tin.

The dispersion medium 24 is at room temperature (about 10-35).
It should be solid (in the range of ° C) (in a solid state) and be in a fluid state when heated to a temperature higher than room temperature (in the range of about 40 to 80 ° C), such as an organic compound. Commonly known substances such as synthetic or natural waxes such as paraffin wax and carnauba wax, natural or synthetic resins, or carboxylic acid esters which satisfy the above conditions can be appropriately used.

The above-mentioned magnetic particles 22 and colored magnetic particles 2
Core material 21 containing 3, 23 ', dispersion medium 24, etc. as main components
Is covered with a shell material 27 such as a polymer to be microencapsulated. Examples of the resin used as the shell substance 27 include commonly used resins such as acrylic resin, methacrylic resin, polystyrene, polyester resin, polyurethane resin, polyurea resin, polyamide resin, epoxy resin and natural resin. It is also possible to use these alone or in combination of two or more.

Microcapsules 1 having the above shell material
The method for producing 5 includes a phase separation method in which a concentrated phase of the polymer is separated around the core substance dispersed in the polymer solution, and a liquid for curing the polymer around the core substance in the polymer solution with a curing test agent for the polymer or the like. Medium-cure coating method, in-situ polymerization method in which the surface of the core material is covered with a polymer by supplying a monomer or a polymerization catalyst from either one of the emulsion in which the core material is dispersed, or the external phase, 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 the internal phase and the external phase is suitable, but the method is not limited to these methods.

In particular, the in-situ polymerization method or the phase separation method in which the magnetic particles 22 as the core substance 21 or the colored magnetic particles 23 and 23 'are uniformly dispersed in the dispersion medium 24 to supply the monomer from the outer phase of the suspension is used. The microcapsules 15 having a uniform particle size and in which the magnetic particles 22 and the colored magnetic particles 23 and 23 ′ can be easily moved can be manufactured by manufacturing the microcapsules 15. The polymerizable monomer used here is acrylic acid ester, methacrylic acid ester,
Styrene and its derivatives, isocyanate, various amines, compounds having an epoxy group and the like are preferable.

Magnetic display devices 1 and 10 of the present invention
Is coated on the support 11 with the microcapsules 15 having the above-described structure together with the binder 16 to form the magnetic display layer 12.
Is formed, and further, the protective support 14 is laminated thereon. Further, a colored layer 13 having transparency can be provided on the magnetic display layer 12.

The support 11 is a synthetic resin such as polyvinyl chloride, polyester, polycarbonate, polymethylmethacrylate, polystyrene, polyethylene terephthalate, natural resin, paper, synthetic paper, metal, ceramics, etc., alone or in combination. Can be used. In addition, its shape can be selected according to the application such as a card shape or a sheet shape, a film shape, and further considering the physical properties required according to the application, for example, strength, rigidity, hiding power, light opacity, etc. It can be appropriately selected.

As the binder 16 in which the microcapsules 15 are dispersed, a water-based binder, a solvent-based binder, an emulsion-based binder or the like is appropriately used.
Further, as the protective support 14, epoxy resin, tetrafluoroethylene or the like, or polyvinyl chloride, polyester, polycarbonate, polymethyl methacrylate,
It is possible to use synthetic resins such as polystyrene and polyethylene terephthalate, and natural resins. This protective support 13
Is required to hold the microcapsules 14 formed on the support 11 and be transparent so that the microcapsules 14 can be seen from the outside. be able to.

The transparent colored layer 13 is formed by coating the magnetic display layer 12 with a pigment or dye dispersed or dissolved in a binder or the like. As the pigment or dye, a pigment alone, a mixture of several pigments,
A mixture of a pigment and a polymer, a dye alone, or a mixture of several dyes can be used. For example, pigments are generally known inorganic pigments such as titanium dioxide, zinc sulfide, lead titanate, zirconium oxide, lead white, cadmium red and cadmium yellow, fine particles of organic pigments such as phthalocyanine pigments, and dyes are azo dyes. Known pigments and dyes such as quinoline dyes and phthalocyanine dyes are used. When a pigment or a mixture of a pigment and a polymer is used, the above pigment or the pigment and the polymer are kneaded and then pulverized, or the pigment or the monomer in which the pigment is dispersed is subjected to emulsion polymerization, suspension polymerization, dispersion polymerization. A method of polymerizing using such a method is used. In this case, the polymer is preferably crosslinkable. As a binder for dispersing and dissolving these pigments or dyes, an aqueous binder, a solvent binder, an emulsion binder and the like are used.

These forming methods include well-known printing methods such as offset printing method, gravure printing method and silk screen printing method, roll coating method, coating method such as knife edge method, and the above-mentioned microcapsules 15. A transfer method using a transfer sheet in the transfer layer, an ink jet method in which the ink containing the microcapsules 15 is sprayed onto a base material, and a solution containing the microcapsules 15 between the support 11 and the protective support 14. Can be prepared by a forming method such as a filling method, and can be appropriately selected from the above-mentioned methods depending on the use and quantity of the information recording medium to be prepared.

Next, an image forming method in the magnetic display of the present invention will be described. FIG. 6 is an explanatory view showing an enlarged cross-section of a part of the magnetic display 1 of the present invention in which the microcapsules 15 containing the suspension in which the magnetic particles 22 are dispersed in the organic solvent 24 are applied on the support 11. is there. Originally made, microcapsule 1
In 5, the magnetic particles 22 are fixed in the dispersion medium 24 in a uniformly dispersed state.

FIG. 7 is an explanatory diagram showing a state when a normal image is erased or when no image is recorded. The entire surface of the magnetic display is uniformly heated, the dispersion medium 24 in the microcapsule is melted, and the magnetic particles uniformly applied from the back surface of the magnetic display cause magnetic particles in the microcapsules of the magnetic display layer 12. 22 is drawn below the microcapsules, and the magnetic display surface has a uniform color tone due to the color of the dispersion medium or light scattering due to the difference in refraction. When the colored layer 13 is provided as in the magnetic display shown in FIG. 2, the color of the colored layer 13 is uniform.

FIG. 8 is an explanatory view showing a state in which recording is performed by applying magnetism from the magnetic generating means having a heating function from above the magnetic display display 1. The dispersion medium 24, for example, wax in the portion of the microcapsule heated by the heat / magnetic head device 32, which is a magnetism generating means with a heating function, is melted, and the magnetic particles 22 in the microcapsule are magnetized above the microcapsule. Attracted to. On the other hand, in the portion that is not heated by the thermal / magnetic head device 32, the magnetic particles 22 do not move inside the microcapsule, and the pigment 23 exists above the microcapsule. Therefore, by heating and magnetically applying the recording portion according to the recording information, an image of the color of the magnetic particles in the recorded portion can be obtained in the color of the pigment in the unrecorded portion. The thermal / magnetic head device 32 is an ordinary magnetic head to which a heating unit such as a heater is added, and the heating unit may have a heating capacity enough to melt the dispersion medium 24 such as wax. .

Since this image formation is simple due to heat of low energy enough to lower the magnetism and viscosity of the organic solvent, recording is easy, and the resolution can be improved by controlling the particle size of the microcapsules. High image formation is possible. Also, when the magnetic particles are attracted to the back surface of the display, the color of the magnetic particles is hidden due to the color of the dispersion medium that exhibits a solid state at room temperature or the light scattering due to the difference in the refractive index. By coloring the magnetic particles, the display can be changed from a color unique to the magnetic particles to an arbitrary color, that is, a color. Furthermore, a thermal / magnetic head device 3 with a heating function
The image formed in No. 2 has a good recording stability because the dispersion medium is fixed at the same time when the dispersion medium returns to room temperature, and since the image cannot be formed only by magnetism except in the melted state, fogging is caused by touching the magnet. It never happens. The display according to the present invention has the mobility of the contained magnetic particles at the time of recording, that is, both the good recording reactivity and the stability of the recorded image. Further, by heating, the magnetic particles can move only in the portion of the organic solvent that is in a fluidized state, so that an image with high resolution can be obtained.

Furthermore, since the microcapsules can be made into a coating solution by mixing with a binder, they can be applied to various supports and can be processed into various shapes, and the manufacturing process is simple. Therefore, the range of applications can be expanded. In particular, when applied on paper, it can be used as information recording paper for household faxes and the like, and can be used as recycled paper because printing and erasing can be performed easily and reversibly by applying heat and magnetism.

Next, FIG. 9 is a conceptual diagram for explaining the structure of the magnetic display device 2 of the present invention. The surface, ie, the display, is used as the image recording means of the magnetic display 1 as shown in FIGS. 10 and 11, respectively. A recording heat / magnetic head drive unit 34 in which a plurality of heat / magnetic head devices 32, which are magnetic generating means with a heating function, are arranged on the screen side, and a back surface as an image erasing means, that is, a surface opposite to the display screen, has a heating function There are provided an erasing thermal / magnetic head drive section 35 in which a plurality of thermal / magnetic head devices 32, which are magnetic generation means, are arranged, and a control means 36 for controlling recording / erasing. The thermal / magnetic head devices 32 and 33 are ordinary magnetic heads to which a heating unit such as a heater is added, and the heating unit may have a heating capacity enough to melt the dispersion medium 24. For example, a permanent magnet having a heater function may be selectively brought close to the surface of the magnetic display display 1.

The recording thermal / magnetic head drive unit 34 corresponds to each thermal / magnetic head device 32 on the basis of the display data obtained by processing the display image data by the control means 36.
To operate. As a result, a predetermined portion of the magnetic display 1 is heated and a magnetic field is applied, and the recording thermal / magnetic head drive unit 34 is moved on the magnetic display 1 by a moving device (not shown) to record an image. Is. The recording thermal / magnetic head drive unit 34 uses one or more thermal / magnetic head devices 32 as a mechanism for moving the thermal / magnetic head drive unit in the main scanning direction and the sub-scanning direction. The display 1 may be scanned in the main scanning direction and the sub-scanning direction for recording.

Similarly, the erasing thermal / magnetic head drive section 35 operates the thermal / magnetic head devices 32 by the control means 36 to heat the erasing portion of the magnetic display 1 to apply a magnetism and not shown. The moving device moves the erasing thermal / magnetic head drive unit 35 on the magnetic display 1 to erase an image.
In addition to the entire erasing by moving the erasing heat / magnetic head drive unit 35 in the main scanning direction of the magnetic display 1, the structure is similar to that of the recording heat / magnetic head drive unit 34, and partial erasure is also possible. It is possible.

[0048]

INDUSTRIAL APPLICABILITY The magnetic display and magnetic display device of the present invention have a magnetic display layer including a microcapsule containing a dispersion medium in which magnetic particles are dispersed and exhibiting a solid phase state at room temperature, and a non-recorded state. The magnetic particles are attracted to the back side, which is one side of the magnetic display, and the surface of the magnetic display, which is the other side, is uniform due to the color of the dispersion medium or light scattering due to the difference in the refractive index. The color tone or the color of the colored layer shows a uniform color tone, and the recording state is scanned from the surface side of the magnetic display by a thermal / magnetic head device having a heating means, and magnetic particles are magnetically displayed by heating and applying magnetic force. Moving to the surface side of the display, a black image is formed by the magnetic particles. For erasing, heating of the entire surface and application of magnetism from the back surface of the magnetic display to the entire surface, or heating and application of magnetism by scanning the back surface of the magnetic display, magnetic particles are attracted below the microcapsules. On the surface of the magnetic display, the color of the dispersion medium or the light scattering due to the difference in the refractive index between the magnetic display and the surface becomes a uniform color or the color of the colored layer, and the image is erased.

That is, in the magnetic display and the magnetic display device of the present invention, the portions to which magnetism is applied are clearly bright and dark so that the portions to which no magnetism is applied are clearly different, the resolution is high, and the image is clear. It has excellent effects such as excellent stability. Furthermore, by using colored magnetic particles as the magnetic particles, colorization is possible.

In the present invention, since image formation can be easily performed by heating at a low temperature and applying magnetism, the energy consumption is low, and the particle size of the microcapsules can be controlled by using the microcapsules in the recording layer. By doing so, the resolution can be increased. Moreover, since the magnetic particles are dispersed in the dispersion medium that shows a solid state at room temperature in the microcapsule and are fixed except during recording, even if magnetism is externally applied after recording the information, the microcapsule can be Stable recording can be obtained without causing the magnetic particles inside to move. In addition, since the area affected by magnetism does not expand by encapsulating microcapsules, the movement of magnetic particles can be almost limited only to the part where heating and magnetism is applied, so the dispersion medium has high resolution and shows a solid state at room temperature. By using, the image stability is also excellent.

Further, since the step of applying the coating liquid containing the microcapsules can be applied, the manufacturing steps of the magnetic display can be simplified.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of a magnetic display according to the present invention.

FIG. 2 shows a structure of a magnetic display according to another embodiment of the present invention.

FIG. 3 is a cross-sectional view showing an example of microcapsules used in the magnetic display layer of the magnetic display according to the present invention.

FIG. 4 is a cross-sectional view showing an example of colored magnetic particles coated with a colored coating layer of the present invention.

FIG. 5 is a cross-sectional view showing an example of colored magnetic particles coated with a colored coating layer and a masking layer of the present invention.

FIG. 6 is an explanatory view showing a state at the time of manufacturing the magnetic display according to the present invention.

FIG. 7 is an explanatory diagram showing a non-recorded state by the erase operation of the magnetic display of the present invention.

FIG. 8 is an explanatory diagram showing a state of the magnetic display of the present invention during recording.

FIG. 9 is a conceptual diagram illustrating a magnetic display device of the present invention.

FIG. 10 is an explanatory diagram illustrating a configuration of a recording thermal / magnetic head drive unit of the magnetic display device of the present invention.

FIG. 11 is an explanatory diagram illustrating a configuration of an erasing thermal / magnetic head drive unit of the magnetic display device of the present invention.

[Explanation of symbols]

 1, 10 Display for Magnetic Display 2 Magnetic Display Device 11 Support 12 Magnetic Display Layer 13 Coloring Layer 14 Protective Support 15 Microcapsule 16 Binder 21 Core Material 22 Magnetic Particle 23 Colored Magnetic Particle 23 ′ Colored Magnetic Particle 24 Dispersion Medium 25 Colored Coating layer 26 Concealment layer 27 Shell material 32, 33 Thermal / magnetic head device 34 Recording thermal / magnetic head drive unit 35 Erase thermal / magnetic head drive unit 36 Control means

Claims (7)

[Claims] 1. A binder comprising microcapsules containing at least magnetic particles and a dispersion medium which is in a solid state at room temperature and is formed by dispersing magnetic particles between supports, at least one of which is a transparent nonmagnetic material. A display for magnetic display, characterized in that a magnetic display layer is formed dispersedly inside. 2. The display for magnetic display according to claim 1, wherein a colored layer having transparency is laminated on the magnetic display layer. 3. The display for magnetic display according to claim 1, wherein the average particle size of the magnetic particles is between 0.1 μm and 10 μm. 4. The display for magnetic display according to claim 1, wherein the magnetic particles are colored magnetic particles. 5. The display for magnetic display according to claim 1, wherein the dispersion medium is an organic compound having a melting point of 35 ° C. or higher and 80 ° C. or lower. 6. The average particle size of the microcapsules is 10
The display for magnetic display according to claim 1, wherein the display is in the range of μm to 1000 μm. 7. A binder, which is a microcapsule containing at least magnetic particles and a dispersion medium having a solid state at room temperature, in which at least one magnetic particle is dispersed, between at least one support made of a non-magnetic material having transparency. A magnetic display for forming a magnetic display layer dispersedly arranged therein, and disposed on the display surface side of the magnetic display, the magnetic particles in the microcapsules partially by heating and magnetic application. A heating magnetism generating means for attracting and moving, and a heating magnetism generating means disposed on the back surface side of the magnetic display for attracting and moving the magnetic particles in the microcapsules by heating and magnetic application. A magnetic display device characterized in that magnetic particles in a capsule are unevenly distributed on one surface.