JPH1185068A - Colored ball and display device and production of colored ball as well as production of display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a display device for which a production process is simple without requiring a precision compsn. adjustment of a glass material and a white material by forming light reflection layers consisting of metals and colored layers on the hemispherical surfaces of microballs. SOLUTION: The light reflection layers consisting of the metals and the colored layers are formed on the hemispherical surfaces of the microballs. The colored balls consist of light transparent balls transmissible in a visible light wavelength range. Colored layers and the light reflection layers are laminated on the hemispherical surfaces, by which the colored balls are formed. If the uncolored side of the colored balls faces an observation side when viewed from the observation side, the observer eventually views the colors of the colored layers (a). When the light reflection layer side of the colored balls face the observation side, natural light 4 is reflected by the spherical light reflection layer of the colored ball and is toward various directions exclusive of an incident direction (b). At this time, the microballs play the role of spherical lenses. The light is scattered in the various directions different from the incident direction of the light, by which the display visible white is made possible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a display device for displaying by rotating a colored ball, a colored ball used in the display device, a method of manufacturing the colored ball, and a method of manufacturing the display device.

[0002]

2. Description of the Related Art In recent years, with the development of information equipment, needs for low power consumption and thin display devices have increased, and research and development of display devices meeting these needs have been actively conducted. Among them, the liquid crystal display device is capable of electrically controlling the arrangement of liquid crystal molecules and changing the optical characteristics of the liquid crystal, and has been actively developed and commercialized as a display device capable of meeting the above needs. However, in the current liquid crystal display device, characters on the screen are difficult to see due to the angle at which the screen is viewed and reflected light, and the burden on vision caused by flickering and low brightness of the light source is still sufficiently solved. Absent. For this reason, research on a new display device with a small burden on vision is being actively studied.

[0003] As a new display device, NK Sheridon
For example, a display device using the rotation of a small ball driven by an electric field has been proposed ("A Twisting Ball Displa").
y ", Proc. of the SID, Vol. 18, No. 3/4, pp. 289-293, 19
1977, U.S. Pat.Nos. 4,126,854, 4,143,103, 5,389,945
No., JP-A-64-42683). This display device uses minute balls, one of which has a white hemisphere and the other hemisphere is black. The balls are arranged in cavities formed in a support, Is filled with a high-resistance liquid so that the ball can freely rotate in the liquid. In this case, depending on the type of liquid,
The charge states of the black and white hemispheres of the ball are different from each other, and by applying an external electric field, the rotation can be controlled so as to face the side where the white or black hemisphere of the ball is observed. Can be displayed.

[0004] Such a mechanical display method is extremely stable against temperature changes and electrical disturbance noise, and does not require power during display due to its memory properties. Further, the display is an ideal display device capable of suppressing eye fatigue caused by flickering of a light source as seen in a liquid crystal device or a cathode ray tube, for displaying by utilizing reflection and scattering of natural light on a ball surface.

[0005] By the way, as a method for producing a two-colored minute ball used for a display device by ball rotation, there are the following methods.
The above-mentioned Sheridon et al. Have proposed a method in which TiO2 is contained in a glass ball at a high concentration to whiten the glass ball, and an insulating black layer 202 is formed on a hemispherical surface of the white glass ball 201 by using a vacuum deposition method. (FIG. 7).

Also, Saito et al. ("A Newly Developed Elect
rical Twisting Ball Display ", Proc. of the SID, p2
49-253, 1982), a two-color ball is formed by the same method, and MgF2 and Sb2S3 are simultaneously deposited on a hemispherical surface of a whitened glass ball using a vacuum deposition method to form a black layer and color-code. doing. When the glass ball is whitened, it is manufactured by using a glass composed of three components of LiO 2, TiO 2 and SiO 2, performing heat treatment to separate components so that light scattering occurs, and forming a surface state composed of different components.

However, when the above method is employed, when a white glass ball is produced, precise adjustment of the composition of the glass material and the white material is required, which causes a problem that the manufacturing process becomes complicated.

Further, a method of merging and curing two color curable droplets in a host liquid, a method of merging two color curable droplets by centrifugal force, and curing and collecting the liquid have been proposed. JP-B-7-67754, JP-A-5-27
No. 9486).

In the former method, a two-color ball is constituted by a material which can be solidified from a liquid in a host liquid, and the latter method also solidifies from a liquid to a spherical solid while being radiated by centrifugal force. Select and use materials.

However, when the above method is adopted, there arises a problem that the boundary between the colored layer forming portion and the non-forming portion becomes unclear.

[0011]

As shown in FIG. 7, a method for dichroic formation of a ball in which a black layer is formed on a white ball by a vacuum deposition method is a method having high production reproducibility by using thin film formation. It is. However, white glass balls for forming a black layer have not been commercialized and are not easily available. For this purpose, it is necessary to produce white micro-balls, but it is necessary to precisely adjust the composition of the glass material, and to provide specialized equipment for performing a heat treatment process for uniformizing the sphere diameter and whitening the ball. It is difficult to manufacture at low cost. For this reason, there is a problem that the material cost of the display device is high and the display device itself cannot be manufactured at low cost. In commercializing such a mechanical display device, it has been desired to reduce the cost of colored balls.

Accordingly, an object of the present invention is to provide a display device which does not require precise composition adjustment of a glass material and a white material and has a simple manufacturing process.

[0013]

A display device according to the present invention which achieves the above object is a display device which performs display by rotating a colored ball, wherein a light reflecting layer made of metal is provided on a hemispherical surface of the minute ball. And a colored layer.

When the light reflecting layer and the colored layer are formed only on the hemisphere of the minute ball, a light transmitting minute ball is used. When a colored layer is formed on the light reflecting layer on the microball, a colored color can be displayed by directing the colored layer toward the observation side. When the uncolored side faces the observation side, the incident light is reflected by the light reflecting layer via the minute balls. At this time, the minute ball plays the role of a spherical lens, and the light is scattered in various directions different from the light incident direction, so that a display that looks white can be realized. When the light reflecting layer is formed on the colored layer on the micro-ball, by pointing the uncolored layer to the observation side, a colored color can be displayed through the micro-ball, and the light reflecting layer is turned to the observation side. In this case, the light incident on the minute ball is reflected by the light reflecting layer having a spherical shape of the minute ball, and is reflected in a direction different from the incident direction, so that white display can be performed.

When the light reflecting layer made of metal is formed on one hemisphere of the microball and the colored layer is formed on the other hemisphere, the microball does not need to be light transmitting.

As described above, it is not necessary to make the fine balls white, and it is possible to obtain or manufacture inexpensive transparent fine balls.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION The light reflection layer has a flat light reflectance over a visible wavelength region in order to perform white display.
And it needs to be high. When the light is absorbed or transmitted in the visible wavelength region, the display color due to the absorption or transmission region appears, so that the color is not white. On the other hand, when the reflectance is low, the display color becomes gray-white, and the contrast is lowered, which is not preferable. Therefore, a preferable regular reflectance is 80% or more in the visible wavelength region. Al, Pt, Ag, or the like can be used as a material having a high regular reflectance.

In the present invention, the hue can be displayed without using a pigment or a dye unlike a colored layer by using a light reflecting layer made of a metal.

The method for forming the colored ball of the present invention includes:
After forming either the light reflecting layer or the colored layer on the hemispherical surface of the microball, the other light reflecting layer or the colored layer may be formed. In addition, by changing the stacking order of the hemispheres, the display colors can be easily inverted.
The colored layer only needs to be able to display different hues as viewed from the observation side by using the difference between the color of the reflected light and the reflection intensity. By coating a colored layer on the surface of the minute ball, two surfaces having different optical characteristics such as the color of reflected light and the reflection intensity are created.

When a black-and-white display is performed, a black colored layer is formed by depositing carbon, TiC, Sb2S3, or the like by a vacuum deposition method, or by simultaneously depositing MgF and Al by vacuum deposition, or Carbon black, Fe3O
A resin or a dye in which a black pigment such as No. 4 is dispersed is coated on the ball surface by using a coating method such as a spin coating method, a spraying method, or a dipping method to form.

The coloring layer is formed by using a thin film forming method suitable for the material used for coloring, and conventionally known techniques such as a vacuum deposition method, a sputtering method, a chemical vapor deposition method, a spinner coating method, and a dip coating. A thin film manufacturing technique such as a method can be used. The coloring layer is preferably a material that is stable in an insulating liquid, has high mechanical strength, and has good adhesion to the ball surface. Further, the color of the colored layer is not limited to black, but may be yellow, magenta, cyan, or the like.

FIG. 8 shows an example of the driving principle of the display device of the present invention.
This will be described with reference to FIG. The display device according to the present invention includes a micro-ball having two layers of a colored layer 2 and a light-reflective layer 3, a support 5 for rotatably supporting the colored ball, and a cavity 7 for allowing the micro-ball to rotate freely. And a driving means comprising electrodes 6 and 6 ′ for rotating the colored balls to display a desired colored layer side and a power supply 8. Further, the cavity is filled with an insulating liquid.

It is known that particles in a liquid exchange electric charges between the particles and the liquid to form an electric double layer, and the particles are positively or negatively charged. In the colored ball of the present invention, the colored layer 2 and the light reflecting layer 3 are formed on the hemispherical surface of the microball, and the other hemispherical surface is uncolored, so that it has regions made of two different substances. Therefore, positive ion particles or negative ion particles are specifically adsorbed on the surface of the colored ball from the insulating liquid, and a surface potential is generated on the surface of the colored ball. For this reason, in the insulating liquid, the charging characteristics are different in each region,
It has a dipole moment in the polar direction of the colored ball. When an electric field is applied to the colored ball, a torque acts on the colored ball to align the pole direction with the electric field direction,
The colored ball aligns any hemisphere in one direction. FIG.
When the uncolored area is negatively charged and the colored layer 2 and the light reflecting layer 3 are positively charged as shown in FIG.
The uncolored side comes to the electrode 6 'to which plus is applied and the colored side to the electrode 6 to which minus is applied. Thus, when the display device of the present invention is observed from the upper part of the drawing, the light reflection layer 3 can be seen. When the direction of the electric field is reversed, the microballs are inverted, and the colored layer 2 can be seen through the light-transmitting ball with the uncolored side facing the observation side.

As shown in FIG. 9, a display medium constituted by a support 5 having a colored ball and a cavity 7 filled with an insulating liquid is shaped, and a plurality of electrodes are arranged on upper and lower surfaces of the display medium. By applying a voltage between the opposed electrodes, a display color according to the polarity of the voltage can be displayed.

As the liquid used for the insulating liquid,
An organic solvent such as toluene or acetone or water can be used as long as the liquid has a high electrical insulating property. However, a non-volatile liquid is preferably used so that the insulating liquid filling the cavity is not volatilized. Particularly, silicone oil is a liquid having a low content of ions and impurities and a high resistance, which is preferable. Further, the insulating liquid has a property of contacting the colored ball, activating the surface of the colored ball, and inducing two different charged states.

The dimensions of the cavities are preferably slightly larger than the colored balls in order to prevent translation of the colored balls as much as possible and to have a memory property.

The electrode used to drive the colored ball needs to be light-transmitting so that the colored layer formed on the surface of the minute ball can be observed from the observation side. For this reason, a transparent conductive film such as SnO2, TiO2, ZnO, and ITO is used.

The support (light-transmitting sheet) needs to be optically transparent in order to display the colored layer of the colored ball, and is made of a hard resin such as polyethylene or polystyrene, silicone rubber, or glass. And so on.

The display device of the present invention can be applied to a light-receiving display device that displays image information such as characters, graphics, and videos using the rotation of a colored ball. Further, the present invention can be applied to a paper display which can be viewed like paper, can be moved like paper, can write an image, can copy an image, can read an image, and can erase an image.

The present invention may take other embodiments.
The second display device of the present invention has a configuration other than dispersing the colored balls together with the transparent insulating liquid in a cavity formed in a support (light transmitting sheet). In this case, only the insulating liquid is interposed between the colored balls.

One example of the second display device of the present invention is shown in FIG.
Explanation will be made using 0. The colored ball 1005 has a hemispherical surface of the light transmitting ball covered with a colored layer and a light reflective layer (not shown). A first transparent substrate 1002 having a first transparent electrode 1001 and a first transparent substrate 1002
The space between the second transparent substrate 1004 having the transparent electrode 1003 and the second transparent substrate 1004 is constituted by a space closed by a sealing portion (not shown), and the space between the colored balls 1005 in this space is filled with the insulating liquid 1006. . This shows a state in which a closed space is filled with an insulating liquid and colored balls are dispersed in the insulating liquid. That is, the colored ball 1005 and the insulating liquid 100
6 is closed by a transparent substrate or the like having a transparent electrode.

Further, in the display device of the present invention, the reflected light may be in a wavelength region other than the visible light wavelength region. For example, if the room is
The display device of the present invention can be applied to an infrared light wavelength region.

[0033]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a female substrate according to the present invention; FIG.

(First Embodiment) FIG. 1 is a sectional view of a colored ball used in a display device according to a first embodiment of the present invention. FIG. 2 is a view for explaining the color of the colored ball seen from the observation side when the natural light 4 is irradiated. The colored ball is composed of a light transmitting ball 1 that transmits light in a visible light wavelength region, and has a hemispherical colored layer 2.
And the light reflection layer 3 are laminated. From FIG. 2, when the uncolored side of the colored ball faces the observation side when viewed from the observation side, the color of the colored layer is seen (FIG. 2 (a)).
When the light reflecting layer side of the colored ball faces the observation side, the natural light 4 is reflected by the spherical light reflecting layer of the colored ball and is reflected in various directions other than the incident direction (FIG. 2).
(B)).

For this reason, as a material of the transparent fine ball, in order to display the display color of the colored layer through the fine ball, the transmittance is preferably as high as possible so as not to reduce the amount of light incident on the fine ball. Since light travels back and forth in the microballs to display, the transmittance is preferably 70% or more so that the ratio of the amount of reflected light to the amount of incident light is not reduced by half.

As a material of the transparent micro-ball, any material may be used as long as it is transparent in the visible light wavelength region. Either an inorganic material or an organic material may be used. preferable. The size of the minute ball is preferably 200 μm or less so that the diameter of the ball is one pixel or less as a display device. Further, in order to obtain the same effect as the scattering by the reflection by the spherical light reflecting layer, the smaller the diameter of the ball, the better. The shape of the minute ball may be a curved shape such as a sphere.

FIG. 3 is a sectional view showing the steps of the method for forming a colored ball of the present invention. In this embodiment, the light transmitting ball 2
As 1, a glass ball having a diameter of 50 μm was used. A cyclized rubber-based photoresist (trade name: OMR83, manufactured by Tokyo Ohka Co., Ltd.) serving as a resin layer 12 is applied on a substrate 11 made of a silicon wafer by a bar coating method to a thickness substantially equal to the radius of a glass ball. , A glass ball is sprinkled, and the photoresist is subjected to a heat treatment and cured to obtain the photoresist shown in FIG.
The hemisphere shown in (a) was embedded to form a microball.
Next, TiC was sputtered on this surface to a thickness of 100 nm.
The colored layer 22 was formed to be black by forming a film (FIG. 3
(B)). Subsequently, Al was formed on the colored layer by electron beam evaporation to a thickness of 200 nm to form the light reflecting layer 23 (FIG. 3C). Thereafter, the photoresist is dissolved and removed with an OMR stripper (trade name, manufactured by Tokyo Ohka Co., Ltd.) to form a hemispherical surface in which a black colored layer and a light reflecting layer are laminated, and the other hemispherical surface is transparent. Fine balls could be formed.

The colored ball is then shrunk to the Sh
In the same manner as in Eridon et al., a sheet-shaped display medium was prepared by dispersing in an elastomer. Specifically, 2
Liquid silicone rubber (Silpot 1 manufactured by Dow Corning)
84) The colored balls were dispersed therein. Next, this dispersion is stretched into a film having a thickness of about 100 μm on a glass substrate,
The silicone rubber was cured by heating at 100 ° C. for one hour. Next, the colored ball-dispersed and cured rubber sheet was peeled off from the glass substrate, and immersed in silicone oil having a viscosity of 1 cs (manufactured by Toshiba Silicone Co., Ltd.) for 24 hours to swell the rubber sheet. −
10 μm). Next, the rubber sheet is
A display device was manufactured by being sandwiched between glass substrates with an O electrode film. When an electric field of ± 100 V is applied to the display device, the colored ball rotates in the cavity, so that a hemispherical surface having a light reflecting layer or an uncolored hemispherical surface appears on the observation side according to the polarity of the electric field. . The response speed was 50 ms or less. Specifically, when an electric field was applied so that the electrode on the observation side became a (+) pole, the electrode rotated so that an uncolored hemispherical surface appeared, and displayed black when viewed from the observation side. When the electric field was reversed, a hemispherical surface with a light reflecting layer appeared, and the incident light was scattered and displayed white as shown in FIG. 2 (b). At this time, the contrast ratio was about 6: 1. Viewing angle characteristics are ± 8
5 ° or more. That is, in the display device of the present invention,
By using a ball in which a colored layer and a light reflecting layer are sequentially formed only on the hemispherical surface of a transparent fine ball, it is possible to provide a display equivalent to a display device using a colored ball in which a black layer is formed on a conventional white ball. It was confirmed. According to the display device of the present invention, a new flexible display device that has a high response speed, has a memory function even when voltage is not continuously applied to the ITO electrode, and has a bending resistance, which has not existed in the past, can be realized.

The colored balls used in this display device do not use white fine balls, but glass balls that can be obtained at low cost can be used. Further, the coloring step is performed only on the hemispherical surface of the fine balls. This is possible in the step of forming a colored layer, and it is easy to produce a colored ball capable of displaying two colors. This has made it possible to keep the price of the display device low. Further, when the manufacturing method of the present invention was used, the boundary between the colored layer forming portion and the non-forming portion (uncolored portion) became clear, and the contrast of the display device could be improved as compared with the related art.

(Second Embodiment) A hemisphere was colored in the same manner as in the first embodiment shown in FIG. 3 except that the order of lamination of the colored layer and the light reflecting layer of the first embodiment was changed. A minute ball was formed. These micro balls are mixed in an elastomer in the same manner as in the first embodiment, molded into a sheet, cured, immersed in silicone oil and swollen to form a cavity, and a sheet-shaped display device is formed. Produced. The display device was sandwiched between glass substrates on which ITO electrodes were formed, and an electric field was applied. Electric field to the observation side electrode is (+)
In the case of (1), an uncolored hemispherical surface appeared, the incident light was scattered by the light reflection layer, and the display device turned white when viewed from the observation side. When the polarity of the electric field was changed, a hemispherical surface with a colored layer appeared and became black.

(Third Embodiment) FIG. 4 is a sectional view of a colored ball used in a display device according to a third embodiment of the present invention. The colored layer 42 is formed on one hemispherical surface of the microball 41, and the light reflecting layer 43 is formed on the other. When the colored layer 42 faces the observation side, the color of the colored layer can be displayed, and when the light reflecting layer faces, the incident light is scattered by spherical reflection and white can be displayed. Since a colored layer and a light reflecting layer are formed on the surface of the ball, it is not necessary to use a light-transmitting minute ball.

FIG. 5 is a sectional view showing the steps of the method for forming a colored ball of the present invention. In the present embodiment, the minute balls 41
Zirconia beads (manufactured by Tosoh Corporation) having a diameter of 50 μm were used. First, a solution of polyamic acid is applied on a substrate 31 made of a silicon wafer to a thickness substantially equal to the radius of the microballs, and the microballs are dispersed and heat-treated. A first resin layer 32 was formed. Next, a 100-nm thick TiC film was formed on the surface by a sputtering method to form a colored layer 43 which became black (FIG. 5A). After this,
A cyclized rubber-based resin solution (trade name O
BC, manufactured by Tokyo Ohka Co., Ltd.) is applied by a bar coating method, and the photoresist is subjected to a heat treatment and cured while being pressed from above with a substrate 34, and is cured by being sandwiched between resin layers shown in FIG. 5 (b). A ball was formed. Next, the first resin layer is formed of TMA.
It was dissolved in an aqueous solution of H (Tetramethyl ammoniumhydroxide) to form microballs in which hemispheres were embedded in the second resin layer shown in FIG. 5C. On the uncolored surface of this micro ball,
Al was formed to a thickness of 200 nm by electron beam evaporation to form a light reflection layer 23 (FIG. 6D). Thereafter, the second resin layer is dissolved and removed with an OMR stripper (trade name, manufactured by Tokyo Ohka Co., Ltd.) to form a colored ball in which a black colored layer and a light reflecting layer are formed for each hemisphere. (FIG. 6 (e)).

This colored ball is mixed with an elastomer in the same manner as in the first embodiment, molded into a sheet, cured, and swelled by dipping the elastomer sheet in silicone oil. Thus, a cavity was formed around each of the colored balls, thereby producing a sheet-shaped display device. When the display device is sandwiched between a glass substrate on which an ITO electrode is formed and an electric field is applied, the colored ball rotates in the cavity, and a hemispherical surface having a light reflection layer formed on the observation side according to the polarity of the electric field, or colored. The hemisphere of the layer appeared. White display was possible by scattering of incident light by the light reflection layer, and black display was possible by the colored layer of TiC. That is, the display device of the present invention was able to perform the same display as a conventional two-color ball in which a black layer was formed on a white ball. According to the display device of the present invention, a novel display device which has a response speed which is unprecedented, has memory properties even without continuously applying a voltage to the ITO electrode, and has bending resistance can be realized. This has made it possible to keep the price of the display device low. Further, when the manufacturing method of the present invention was used, the boundary between the colored layer forming portion and the non-forming portion (uncolored portion) became clear, and the contrast of the display device could be improved as compared with the related art.

(Fourth Embodiment) FIG. 11 shows a schematic configuration of an example of a display device using the first embodiment of the present invention. FIG. 11A is a plan view, and FIG. 11B is a cross-sectional view. First, a 100 μm thick rubber sheet 2104 formed by dispersing the colored balls 2103 described in Example 1 was formed on a 100 μm thick PET film 2101 entirely covered with a transparent lower ITO electrode 2102.
On such a sheet, a 100 μm-thick P having a transparent upper ITO electrode 2106 patterned in a desired shape.
The ET film 2105 was pressed in a direction in which the upper ITO electrode 2106 faces the rubber sheet 2104. It is necessary to select the shape and size of the upper ITO electrode 2106 according to the desired resolution, but in the present embodiment, a conventionally known 7-segment type was used for simplicity. Each upper electrode 2106 was connected to a pulse generator 2107, and a rectangular wave having a peak value of 100 V and a pulse width of 50 ms was applied to all the electrodes, and the whole surface was brought into a white state. Next, an arbitrary one of the upper ITO electrodes 2106 is selected by a switch 2108, and a pulse having a polarity opposite to that of the previous one is applied.
It was confirmed that 103 rotated and turned black, and it was possible to display (a part of a number or alphabet) using a combination of segment shapes. Further, when a pulse having the opposite polarity (the same polarity as the first pulse) was applied to the black display segment, it was confirmed that the black display returned to the white display again.

(Fifth Embodiment) Instead of the 7-segment type configuration used in the fourth embodiment, the lower electrode 2112 and the upper electrode 2113 are composed of stripe-shaped ITO electrodes. The width of the stripe-shaped ITO electrode and the interval between the electrodes were 40 μm. Lower electrode 2112 and upper electrode 21
13, a display device arranged orthogonal to each other was prepared. The schematic configuration of such a display device is shown in FIG.
(B). All lower electrodes 2112 and all upper electrodes 211
A rectangular wave having a peak value of 100 V and a pulse width of 50 ms was applied to 3 using a pulse generator (not shown), and the entire surface was made white. Next, an arbitrary lower electrode 2112 and an upper electrode 2113 are selected, and a pulse of opposite polarity is applied between the electrodes using the above-described pulse generator. In a region where both electrodes intersect, the colored ball 2103 rotates. , And turned black. That is, it was confirmed that a desired region can be displayed in black by selecting a combination of electrodes to which a pulse is applied.
In addition, it was confirmed that by applying a pulse having a polarity opposite to that of a pulse that causes black display, the black display portion returns to white display again.

[0046]

As described above, in a display device which performs display by rotating a colored ball, a plurality of minute balls are arranged two-dimensionally close to each other, and a metal is formed on the hemispherical surface of the minute ball. By forming the light reflecting layer and the colored layer, it is not necessary to make the micro balls white,
Inexpensive micro balls that do not go through the whitening process can be used, and the price of the display device can be kept low.

Further, it was possible to provide a display device which does not require precise adjustment of the composition of the glass material and the white material and whose manufacturing process is easy.

The method for forming the colored ball of the present invention is as follows.
After forming either the light reflecting layer or the colored layer on the hemispherical surface of the microball, the other layer may be formed. Since the colored layer and the light reflecting layer are sequentially laminated only on the hemispherical surface, fabrication is easy. Met. Further, by changing the stacking order of the colored layer and the light reflecting layer, it was possible to invert the display color.

[Brief description of the drawings]

FIG. 1 is a sectional view of a minute ball used for a first display device of the present invention.

FIG. 2 is a diagram illustrating a display color of a minute ball seen from an observation side according to the first embodiment of the present invention.

FIG. 3 is a view showing a process of forming a micro ball according to the first embodiment of the present invention.

FIG. 4 is a sectional view of a minute ball used in a display device according to a third embodiment of the present invention.

FIG. 5 is a view showing a process of forming micro balls according to a third embodiment of the present invention.

FIG. 6 is a view showing a process of forming micro balls according to a third embodiment of the present invention.

FIG. 7 is a cross-sectional view illustrating a microball of a conventional example.

FIG. 8 is a cross-sectional view illustrating the operation principle of the present invention.

FIG. 9 is a cross-sectional view illustrating a display device of the present invention.

FIG. 10 is a cross-sectional view illustrating a second display device of the present invention.

FIG. 11 is a diagram of a display device used in Embodiment 4 of the present invention.

FIG. 12 is a diagram of a display device used in Embodiment 5 of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 21 Light transmission ball 2, 22, 42 Coloring layer 3, 23, 43 Light reflection layer 4 Natural light 11, 31, 34 Substrate 12 Resin layer 32 1st resin layer 33 2nd resin layer 41 Micro ball 201 White glass ball 202 Black layer 5 Support (light transmitting sheet) 8 Power supply 6, 6 'Electrode 9, 9' Glass substrate

Claims (24)

[Claims] 1. A display device for performing display by rotating a colored ball having two surfaces having different optical characteristics, wherein the colored ball has two surfaces having different charged states. Has a colored layer and a metal light-reflective layer coated on a part of the surface of a ball made of a light-transmitting material, and the other surface has a ball surface made of the light-transmitting material exposed. A display device. 2. The display device according to claim 1, wherein the one surface has a hemispherical surface of a ball made of a light transmitting material covered with two layers of the coloring layer and the light reflecting layer. 3. The display device according to claim 1, wherein the two layers are layers in which the light reflection layer is stacked on the coloring layer. 4. The display device according to claim 1, wherein the two layers are layers in which the coloring layer is stacked on the light reflecting layer. 5. The display device according to claim 1, wherein the ball made of a light transmitting material is made of a visible light wavelength region transmitting material. 6. The display device according to claim 1, wherein the ball made of the light transmitting material is made of glass containing silicon dioxide as a main component. 7. A display device which performs display by rotating a colored ball having two surfaces having different optical characteristics, wherein the colored ball has a colored layer on one surface and a light made of metal on the other surface. A display device characterized by having two surfaces having different charge states because the reflective layer is covered. 8. A colored ball used for the display device according to claim 1. Description: 9. A method for producing a colored ball having two surfaces having different optical characteristics, wherein a step of forming a colored layer on a partial surface of a ball made of a light transmitting material, and a step of forming a metal on the colored layer Forming a light reflecting layer. 10. The method according to claim 9, wherein the step of forming a colored layer on a partial surface of the ball made of the light transmitting material is a step of forming the colored layer on a hemispherical surface of the ball made of the light transmitting material. Of manufacturing colored balls. 11. A step of embedding a ball made of the light transmitting material on a photoresist layer, a step of forming the colored layer on a surface where the ball made of the light transmitting material is exposed, and The method for producing a colored ball according to claim 9, further comprising a step of forming a light reflecting layer and a step of removing the photoresist layer. 12. A method for manufacturing a display device in which a display is performed by rotating a colored ball having two surfaces having different optical characteristics, wherein a colored layer is formed on a partial surface of the ball made of a light transmitting material. Forming a light reflecting layer made of metal on the coloring layer, dispersing the ball on which the coloring layer and the light reflecting layer are formed in a display medium, and forming an electrode on the display medium surface. Forming a display device. 13. The method according to claim 12, wherein the step of forming a colored layer on a partial surface of the ball made of the light transmitting material is a step of forming the colored layer on a hemispherical surface of the ball made of the light transmitting material. A method for manufacturing a display device. 14. A step of embedding a ball made of the light transmitting material on a photoresist layer, a step of forming the colored layer on a surface where the ball made of the light transmitting material is exposed, and 13. The method according to claim 12, further comprising: forming a light reflecting layer; and removing the photoresist layer.
A method for manufacturing a display device according to claim 13. 15. A method for manufacturing a colored ball having two surfaces having different optical characteristics, wherein a step of forming a light reflecting layer made of metal on a partial surface of a ball made of a light transmitting material; Forming a colored layer thereon. A method for producing a colored ball, comprising: 16. The step of forming a light reflecting layer on a partial surface of a ball made of a light transmitting material is a step of forming the light reflecting layer on a hemispherical surface of a ball made of a light transmitting material. 3. The method for producing a colored ball according to item 1. 17. A step of embedding a ball made of the light transmitting material on a photoresist layer; a step of forming the light reflecting layer on a surface where the ball made of the light transmitting material is exposed; Forming the colored layer on the substrate, and removing the photoresist layer.
A method for producing a colored ball according to claim 5 or claim 16. 18. A method of manufacturing a display device in which a display is performed by rotating a colored ball having two surfaces having different optical characteristics, wherein a light reflecting layer made of a metal is formed on a partial surface of the ball made of a light transmitting material. Forming a colored layer on the light reflecting layer, dispersing the ball on which the colored layer and the light reflecting layer are formed in a display medium, and forming an electrode on the display medium surface. Forming a display device. 19. The step of forming a light reflecting layer on a partial surface of a ball made of a light transmitting material is a step of forming the light reflecting layer on a hemispherical surface of a ball made of the light transmitting material. 6. The method for manufacturing a display device according to claim 1. 20. A step of embedding a ball made of the light transmitting material on a photoresist layer; a step of forming the light reflecting layer on a surface where the ball made of the light transmitting material is exposed; Forming the colored layer on the substrate, and removing the photoresist layer.
A method of manufacturing a display device according to claim 8. 21. A method of manufacturing a colored ball having two surfaces having different optical characteristics, wherein a step of forming a colored layer on one surface and a step of forming a light reflecting layer made of metal on the other surface. And a method for producing a colored ball. 22. A step of embedding a ball on a first photoresist layer, a step of forming the colored layer or the light reflecting layer on a surface where the ball is exposed, and a step of forming the colored layer or the light reflecting layer. Covering the formed ball surface with a second photoresist layer, removing the first photoresist layer, and forming the light reflecting layer or the colored layer on the exposed ball surface. 22. The method for producing a colored ball according to claim 21, further comprising: removing the second photoresist layer. 23. A method for manufacturing a display device in which a display is performed by rotating a colored ball having two surfaces having different optical characteristics, wherein a step of forming a colored layer on one surface and a step of forming a metal layer on the other surface are performed. A display comprising: forming a light-reflective layer comprising: a step of dispersing a ball on which the colored layer and the light-reflective layer are formed in a display medium; and forming an electrode on the surface of the display medium. Device manufacturing method. 24. A step of embedding a ball on a first photoresist layer; a step of forming the colored layer or the light reflecting layer on a surface where the ball is exposed; Covering the formed ball surface with a second photoresist layer, removing the first photoresist layer, and forming the light reflecting layer or the colored layer on the exposed ball surface. 24. The method of manufacturing a display device according to claim 23, further comprising: removing the second photoresist layer.