JP3932570B2 - Electrophoresis device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to electrophoresis DoSo location utilizing that the charged particles in the medium by applying a voltage to move.
[0002]
[Prior art]
Conventionally, electrophoresis DoSo location 20 is known, as shown in FIG. The electrophoresis dynamic equipment 20, at least one of the two eg glass substrates 21, 22 of the translucent, through the partition wall 23 to face each other with a predetermined distance from each other, closed by the glass substrates 21, 22 and the partition wall 23 A space 24 is configured. Transparent electrodes 25 and 26 such as planar ITO are fixed to the inner surfaces of the pair of glass substrates 21 and 22 facing each other. Then, the closed space 24, electrophoresis dynamic content dispersion liquid 27 is accommodated. The electrophoresis dynamic content dispersion liquid 27, for example a colored dispersion medium 27a colored in black, contains charged particles (electrophoretic particles, for example, white pigments) of white are dispersed in the dispersion medium 27a and 27b.
[0003]
Such electrophoresis DoSo location 20, to the pair of electrodes 25 and 26, for example, as shown in FIG. 5 (A), a positive voltage is applied to the upper electrode 25, the lower electrode 26 When a negative voltage is applied, the negatively charged white pigment 27b is electrophoresed toward the anode by Coulomb force, and the white pigment 27b adheres to the upper anode electrode 25. This state of the electrophoresis DoSo location 20, when observed from the eye position as shown in FIG. 5 (A), parts white pigment 27b is to form a layer adhering to the transparent electrode 25 and the glass substrate 21 It will appear white through.
[0004]
On the other hand, if the polarity of the applied voltage is reversed, as shown in FIG. 5B, the white pigment 27b adheres to the facing electrode 26 to form a layer and is observed from the position shown in the figure. since the layer of the white pigment 27b is hidden behind the black dispersion medium 27a, electrophoresis Dopa channel would appear black.
[0005]
When the voltage application is stopped, once the white pigment 27b has adhered to the electrode, it is not necessary to apply a voltage other than maintaining the adhesion state.
This principle of electrophoresis DoSo location 20, as shown in FIG. 6, is often used in generally upright in the direction of gravity (in the drawing direction A).
[0006]
[Problems to be solved by the invention]
However, the dispersion used for such conventional electrophoresis DoSo location 20, the electrophoretic particles 27b in a liquid dispersion medium 27a is obtained by dispersing a surfactant, etc., the liquid dispersion medium 27a and the electrophoretic particles Due to the difference in specific gravity of 27b, the electrophoretic particles 27b may settle with time, causing display unevenness and the like, which may deteriorate the display quality.
[0007]
Such as a method to prevent a decrease in display quality due to sedimentation of electrophoretic particles 27b, as shown in FIG. 7, a plurality of cells in the porous spacer 31 inside the closed space of the electrophoresis DoSo location 30 There is a method of dividing into 32. In the method of dividing the inside of the cell 32 by the porous spacer 31 and preventing the sedimentation of the electrophoretic particles 33b, the effect of preventing the sedimentation of the electrophoretic particles 33b is increased as the pore diameter of the porous spacer 31 is reduced. The reason is that if the pores of the porous spacer 31 are large, the electrophoretic particles 33b pass through the pores and the electrophoretic particles 33b are settled. If the pores of the porous spacer 31 are small, the electrophoretic particles This is because 33b becomes difficult to pass through the hole.
[0008]
However, in the above method, it occurs a new problem that the manufacturing of the porous spacers 31 The smaller the pore size of the porous spacers 31 (and thus the production of electrophoresis DoSo location 30) becomes difficult.
The present invention has an object to provide an electrophoresis DoSo location production with excellent easy and display quality.
[0009]
[Means for Solving the Problems]
The electrophoretic display device of the present invention includes a pair of substrates and a pair of electrodes disposed on the pair of substrates so as to face each other,
Partitions are provided at both ends of the pair of electrodes, porous spacers are arranged between the partition walls at predetermined intervals to form closed spaces with the opposing electrodes, and charged particles are contained in the dispersion medium in each closed space. The distance between the electrodes is continuously changed in one direction between the opposing electrodes of at least one of the opposing electrodes that define each closed space. It is characterized in that it is used with the shorter distance between the opposing electrodes defining each closed space facing upward and the longer distance facing downward .
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter will be described in detail one embodiment of the electrophoresis DoSo location of the present invention with reference to accompanying drawings.
Figure 1 is a longitudinal sectional view of the electrophoresis DoSo location 1 showing this embodiment, and FIG. 2 is a partially enlarged view.
[0012]
As shown in FIG. 1, electrophoresis DoSo location 1, at least one of the substrates 2 and 3 having a light-arranged opposite with a predetermined interval through a partition wall 4 located on the left and right ends, the substrates 2 , 3 and the partition wall 4 form a closed space 5.
[0013]
Among them, the substrate 3 positioned on the lower side in FIG. 1 has a plurality of inclined surfaces 6 that are continuously lowered from the left side to the right side in the drawing on the upper surface side in the drawing of the acrylic resin. After the gold electrode film (electrode) 7 is formed by vapor deposition on the plurality of inclined surfaces, the silicon rubber porous spacer 8 is formed on the top portions 6a side of the plurality of inclined surfaces 6 by a lift-off method using a dry film resist. Are formed respectively. Thus, the internal closed space 5 of electrophoresis DoSo location 1 formed by the substrate 2 and 3 and the partition wall 4 is, will be divided into a plurality of cells 9 by the plurality of porous spacers 8. For example, as shown in FIG. 2, the inclined surface 6 has a length b = 25 to 100, for example, b = 50, with respect to the height a = 1 of the apex 6a of the inclined surface 6. Formed.
[0014]
On the other hand, in FIG. 1, the substrate 2 positioned on the upper side has an ITO transparent electrode film (electrode) formed on the lower surface side of the transparent synthetic resin (for example, PET) (the surface side facing the lower substrate). Yes.
As described above, the substrate 2 and 3, electrophoresis dynamic partial dispersion liquid 11 in the closed space 5 which is formed by the partition walls 4 and the porous spacer 8 is accommodated, this electrophoresis DoSo location 1 is formed by It will be. Incidentally, electrophoresis dynamic content dispersion liquid 11 is provided with a colored dispersion medium 11a, dispersed electrophoretic particles (titanium oxide, zinc sulfide, etc.) to the dispersion medium 11a and 11b.
[0015]
Electrophoresis DoSo location 1 configured as described above, as shown in FIG. 3, so that the top portion 6a side of the inclined surface 6 (the left end side of the electrophoresis DoSo location 1 shown in FIG. 1) is in the upper And used in a gravitational direction (A direction in the figure). Therefore, electrophoresis DoSo location 1, the distance between the electrodes of the upper side of each cell 9 divided by a porous spacer 8 is narrow, so that the distance between the electrodes of the lower side is widened, the distance between electrodes changes.
[0016]
As a result, electrophoresis DoSo location 1 according to this embodiment, when the electrodes 7 and 10 are energized, the electric field intensity of the upper side of each cell 9 is higher than the lower side, the electrophoretic particles 11b Since the moving speed is also increased, sedimentation of the electrophoretic particles 11b on the upper side of each cell 9 can be effectively suppressed, display unevenness can be reduced, and display performance in repeated display can be greatly improved. .
[0017]
In the above embodiment, as shown in FIGS. 1 and 2, the inclined surface 6 is formed in a linear shape as a mode in which the distance between both electrodes is continuously changed. However, it may be appropriately modified to a curved shape or the like, and both electrodes 7 and 10 may be inclined surfaces or the like. The number of the number and the porous spacer 8 of the inclined surface 6 is not limited to this embodiment can be modified appropriately depending on the size of the electrophoresis DoSo location 1. Further, in the present embodiment, as shown in FIG. 1, a mode in which the laterally closed space 5 in the figure is divided into a plurality of cells 9 by the porous spacer 8 is shown. Alternatively, the closed space 5 may be divided into a plurality of parts. In addition, the materials and method for forming the substrate 2, electrodes, etc., as long as it applies to electrophoresis DoSo location 1, forming method can be applied to the formation method, also commonly known.
[0018]
【The invention's effect】
As is clear from the above description, the electrophoresis device of the present invention divides the closed space formed by the substrate and the partition into a plurality of cells by the porous spacer , and at least one of the electrodes facing each cell is Since the distance between the electrodes is inclined so that the distance between the electrodes changes continuously, it is used so that the smaller distance between the electrodes of each cell is on the upper side. The electric field strength on the upper side becomes higher than that on the lower side, the sedimentation of the electrophoretic particles on the upper side of each cell is suppressed, the occurrence of display unevenness is reduced, and the display performance in repeated display is greatly improved.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view of the electrophoresis DoSo location of an embodiment of the present invention.
FIG. 2 is an enlarged view of a main part of FIG.
Figure 3 is a use state view of the electrophoresis DoSo location showing an embodiment of the present invention.
Figure 4 is a longitudinal sectional view of a conventional electrophoresis DoSo location.
Figure 5 is a working state diagram of a conventional electrophoresis DoSo location, a 5 (a) is diagram a first operating state, FIG. 5 (b) is the second operating state diagram .
Figure 6 is a use state view of a conventional electrophoresis DoSo location.
Figure 7 is a longitudinal sectional view of the electrophoresis DoSo location showing another conventional example.
[Explanation of symbols]
1 electrophoresis DoSo location 2,3 substrate 4 partition 5 closed space 7,10 electrodes 8 porous spacer 9 cell 11 electrophoresis dynamic partial dispersion liquid 11a liquid phase dispersion medium 11b electrophoretic particles

Claims (1)

A pair of substrates;
A pair of electrodes disposed to face each other on the pair of substrates,
A partition is provided at both ends of the pair of electrodes, a porous spacer is disposed between the partitions at a predetermined interval to form a closed space with the opposing electrode,
A dispersion liquid in which charged particles are dispersed in a dispersion medium is accommodated in each closed space,
Tilting at least one of the opposing electrodes defining the closed spaces so that the distance between the electrodes continuously changes in one direction between the opposing electrodes ;
The shorter distance between the opposing electrodes defining each closed space is used with the shorter one at the top and the longer one at the bottom ,
An electrophoretic display device.

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