JPH0448624B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION 1. The present invention relates to an electrical movement control device for a liquid based on a new principle, which electrically controls the movement of a colorless or colored liquid, and which is particularly applicable to ink recording devices and the like. It is something.

Conventionally, several methods have been proposed for controlling the electrical movement of liquid as described above, and these are widely used in ink recording devices and the like.

The first method is to apply a voltage pulse to a piezoelectric element to move and eject the liquid forming the ink from a pore nozzle into space, and to modulate the conventional methods. The second method is to charge liquid material from a thin nozzle using ultrasonic waves or air pressure, eject it into space, and modulate its movement by accelerating or deflecting the ejected liquid droplets with a high electric field. The third method is to form a meniscus of liquid in advance, apply a high electric field, and use the Coulomb force to fly and modulate the liquid to move.
The fourth method is a method proposed by the present inventor (Kobashi), in which a liquid is supplied through a porous membrane into a narrow gap by electroosmosis, and this electroosmotic pressure is used to supply the liquid from the narrow gap. This is a movement modulation method that reversibly protrudes the body.

However, the conventional first and second methods have high resolution,
It is difficult to create multiple nozzles at narrow intervals, which is essential for high-speed ink recording, and the second and third methods require modulation of a high voltage of 1 kV or more due to the use of Coulomb force, and the equipment itself is expensive. , becomes complicated. The fourth method is high-density multi-nozzle formation,
Although it has many advantages such as low-voltage driving, since it uses the effect of the liquid material protruding from the gap, there are constraints on equipment design due to the length of the protrusion. Development of electrical displacement modulation control principles is required to realize even higher performance ink recording devices.

The present invention aims to provide an electrical movement control device for a liquid based on a new principle that is useful from the above points of view, and to improve its application to ink recording devices, particularly ink recording devices based on the fourth method. .

To describe the present invention more specifically, a plurality of mutually insulated electrodes are arranged on the surface of a fixed dielectric base material, and the electrode gap between these electrodes is changed,
An electroosmotic liquid is placed on the base material surface, a voltage is applied between adjacent electrodes, and the liquid is electrically heated in response to this voltage. The present invention relates to an electrical movement control device for a liquid based on the principle of movement control.

Here, electroosmosis refers to interfacial motion in which the liquid moves relative to the solid dielectric when a liquid is placed on a solid dielectric and an electric field (voltage) with a parallel component is applied to the contact interface. Defined as a general term for electric phenomena.

In addition, liquid materials are not limited to colored or non-colored materials, and are not limited to liquid materials themselves, such as solutions,
A general term for materials with fluidity, regardless of whether they are mixtures or suspensions.

Hereinafter, aspects of the present invention will be described in detail with reference to Examples. Figures 1a, b, and c are perspective partial structural views of an embodiment of the liquid electromovement control device according to the present invention, showing the power supply system, and in particular, this example is for explaining the operating principle. .

In the figure, 1 is a signal voltage circuit, 2 is a switch circuit, and 100 is a movement control element.

Reference numeral 200 is a colorless or colored liquid whose movement can be controlled electrically, and is placed on the surface 11 of the solid dielectric base material 10 in the form of a plate or film. Electrodes forming movement control element 100 together with base material 10
_o-2 ... _o ... _o+2 is made of, for example, a metal oxide conductive film such as S _o O ₂ or a metal vapor deposition film such as A _u . electrode _o-2
… _o … The width W of _o+2 is kept constant in this example regardless of areas A, B, and C, and the electrode gap G and arrangement pitch P are discontinuous at the junction of each area A, B, and C. Changes to G and P in each region are constant in the A region, continuously decrease toward the edge 12 in the B region, and continuously increase toward the edge 13 in the C region.

The materials of the liquid material 200 and the dielectric base material 10 are
_o-2 ... _o ... _o+2 When a voltage is applied between them, the liquid 200 electro-osmoses into the surface 11 of the base material 10, and the surface 11 of the base material 10 electro-osmoses the liquid 200. The correlation is selected as follows.

The liquid body 200 can be formed by adding a surfactant or a charge control agent to a liquid material, whether aqueous or non-aqueous, as needed. Further, when the liquid material 200 is used to form a colored so-called recording ink, a coloring agent such as a dye or a pigment may be dissolved or mixed therein, or a vehicle material may be added to form a solution or a mixture.

For high-sensitivity operation, the liquid material 200 is selected from a material with a low viscosity of, for example, 10 centipoise or less, and from the viewpoint of low power consumption and prevention of dielectric breakdown, its resistivity is, for example, 10 ⁶ -cm or more, and the applied voltage is It is desirable to select a signal voltage within 5 V per 1 μm of electrode gap W.

From this point of view, the liquid material 200 mainly contains an organic solvent, and the colorant is an oil-soluble dye (i.e.
It is desirable to use solvent dyes.

The liquid material 200 is made of, for example, almost colorless and transparent γ-methacryloxypropyltrimethoxysilane. In this case, the coloring agent for the black ink may be a mixture of Bayer's Maccaresque Blue FR and Kanto Kagakusha's Oil Red Mello;
For the blue ink, Bayer's Macrolex Blue RR, for the yellow ink, Ceres Yellow 3G, for the red ink, Arimoto Kagakusha's Oil Red 5303, etc. are mixed and dissolved at a weight ratio of 2 to 5%. Those that have undergone a certain period of time are used.

The colorless and colored liquids 200 as in the above example are made of soda lime, borosilicate glass, borosilicate glass,
If you choose quartz glass, ceruseum acetate, etc., between the pair of electrodes, in the direction of the electrodes that have a negative voltage polarity relationship,
Surface 11 is electroosmotic.

In addition, when the surface 11 is electroosmotic in the direction of the electrodes having a positive voltage polarity relationship, phenyltriethoxysilane or the like may be used as the liquid material.

In the following description, for convenience of explanation, the liquid material 200
Taking as an example a case in which electroosmosis occurs in the direction of the negative electrode, the same can be applied in a configuration in which electroosmosis occurs in the direction of the positive electrode by selecting the voltage polarity relationship described below to be opposite polarity.

Thus, in FIG. 1a, the switch S _o-2 ...S _o ...S _o+2 of the switch circuit 2 is at terminal b and the electrode _{o-
1 ... o} ... _o+2 are all at the same potential, so no electroosmosis occurs on the surface 11, and when the base material 10 is held horizontally, the liquid 200 has a uniform thickness over the entire surface. have

However, in the figure, when the switch S _o is connected to the C terminal, the on voltage, which is a negative voltage such as V _o = V _c , is applied to the electrode _o.
Consider the case where Vc is applied.

Figure 1b shows the electrodes _o-1 , _o , _o+1 in the above case.
This is a partially enlarged and extracted partial diagram to qualitatively explain the operating state. Electrode _o is adjacent to _o-
1. Since a negative potential is formed with respect to _o+1 , the liquid material 200 flows from the electrode _o-1 and _o+1 side to the electrode _o side,
It is concentrated by electroosmosis as illustrated by arrows 201A, 201B, and 201C in the figure. Note that the length of the arrow is qualitatively displayed in correspondence with the speed and pressure of electroosmosis.

The electroosmotic velocity and electroosmotic pressure of the liquid material 200 against the base material surface 11 increase as the electric field strength Vc/G related to the electrode gap G increases, and decrease as the electric field strength Vc/G decreases. In region A, G is constant, so there is no non-uniformity in the velocity and pressure of electroosmosis 201A in the length direction of electrode _o .
Therefore, the liquid 200 concentrated on the electrode _o is
It can be pushed out either in the direction of area C as shown by arrow 202AC or in the direction of area B as shown in arrow 202AB, and its directionality is unstable.

However, in region B, the closer to the edge 12 the electrode gap G becomes narrower, and therefore the speed and pressure of the electroosmosis 201B also increase, and conversely, the further away from the edge 12 the smaller the electrode gap G becomes.

In addition, the electrode width V is constant. Therefore, edge 1
The closer it is to 2, the larger the amount of liquid 200 that concentrates and rises on the electrode _o per unit time. Therefore, this concentrated liquid 200 is as shown by arrow 202B.
It is pushed out in the direction of area A on electrode _o .

On the other hand, in region C, the closer to the edge 13, the larger the arrangement pitch P and the electrode gap G, and therefore the electric field strength V _o /G, and therefore the velocity and pressure of the electroosmosis 201C concentrated on the electrode _o . Become small. Therefore, in region C, liquid 20 concentrated on electrode _o
0 is an arrow 20 from the area A side toward the edge 13.
It is pushed out like 2C.

In this way, in combination with the movement 202B, the liquid material 200 moves 201AC and 201AC in the area A.
The instability of the movement as shown in 01AB is eliminated, and the direction is fixed to the area C side as shown by the arrow 202A.

In this way, in the state shown in Figure 1b, the electrode
On V _o , the liquid 200 against the substrate surface 11
By electroosmosis 201A, 201B, 201C, liquid 200 becomes 202B, 202A, 202
The movement of the liquid _material 200 is controlled as shown in FIG.
A liquid body portion 210 controlled in accordance with V _o is focused and formed. The amount of this protuberance 210 is determined by the on-voltage
It increases with the amplitude of the on-voltage V _o −V _c .

From the state shown in FIG. 1b, switch S _o of switch circuit 2 is connected to terminal a, and a positive voltage of V _o =V _A is applied to electrode _o .

As shown in Figure 1c, electroosmosis 2 in Figure 2b
02A, 202B, 202C are respectively 201A',
201B', 201C', the electrodes are in opposite directions.
Substrate surface 11 on _o and between electrodes _o and _o-1 , _o+1
The upper liquid 200 electroosmoses to the electrodes _o-1 and _o+1 . This electroosmosis is more remarkable in region A than in region C, and more remarkable in region B than in region A, and the electroosmosis 202C' in region C becomes more remarkable as it leaves the edge 13, and in region B, the closer it gets to the edge 12. .

Liquid material 20 based on significant electroosmosis in this region B
By sucking up the liquid material 200, the bulges 210 of the liquid material 200 are caused by the arrows 202C', 202A', 20
2B', and finally disappears as shown in the figure, not only covering the entire area above the electrode _o , but also covering the entire area above the electrode _o+.
A liquid-absent portion 211 is formed on the base material surface 11 between ₁ and _o-1 .

Thus, as described above, by arranging a plurality of electrodes and changing the electrode gap G between these electrodes to at least either discontinuous or continuous,
When an on-voltage Vc is applied to a target electrode so that the liquid material 200 gathers through electroosmosis with respect to adjacent electrodes, the liquid material 200 moves on the electrode in the direction in which the electrode gap G becomes larger. The formation of a bulge 210 of liquid material focused on the tip of the electrode is controlled electrically.

On the other hand, when the off-voltage V _A with the opposite polarity is applied, the liquid 200 moves in the direction in which the electrode gap G becomes narrower, and the liquid on the target electrode not only bulges 210 but also Almost all of the body 200 is sucked up, except for the part that is thinly electrochemically attached to the electrode surface, and a liquid-absent part 211 is electrically formed.

Note that in this example, the electrode width W was chosen to be constant, but it is also possible to choose the electrode width W to be wider in areas where the electrode gap G is narrow and to be narrower in areas where the electrode gap G is wide. As shown in Figure 2, the electrode gap G
The electrode width W can also be selected to be narrow in areas where the electrode gap G is narrow, and wide in areas where the electrode gap G is wide.

Of the above, the former has the advantage that the electrodes can be arranged as electrodes and the arrangement pitch can be made constant, and in this case, the electrode design is easy. On the other hand, in the latter case, since the electrode width W is narrow in the narrow part of the electrode gap G, the liquid material 200 is quickly concentrated in this part.
Therefore, there is an advantage that the effect of extrusion 202 of the liquid material 200 by electroosmosis 201 from this portion can be effectively utilized. Note that the electrode width W may not be changed in the same way for all electrodes, but may be set to a constant width for every other electrode, or may be changed differently.

In any case, in the present invention, via the switch circuit 2, the
The off-voltage V _A is applied to the target single or multiple electrodes,
By selectively applying the on-voltage _Vc , the electrical movement of the liquid material 200 can be controlled, and a liquid material raised portion 210 and a liquid material absent portion 211 can be selectively formed at the tip of the electrode.

Note that when the electrode gap G is extremely narrow compared to _others as shown in _FIG . may flow out to the edge 12 side.

Since this outflow reduces the effect of the movement 201 of the liquid material 200, it is solved by providing outflow prevention means on the side of the edge 12 where the electrode gap G is narrow.

This effective means, as illustrated in Figure 2,
The method is to apply and install the outflow prevention agent 300 in the form of a narrow strip. The spill prevention agent 300 has, for example, a surface tension of
An extremely small fluororesin oil barrier of approximately 11 dyne/cm (for example, the product name of Sumitomo 3M Co., Ltd.)
It can be formed by applying a thin layer of Flncrad FC-721), by gluing an insulating prism such as plastic material, or by applying an adhesive.

FIG. 3 is a perspective structural view and a diagram showing a power supply system of another embodiment of the liquid electric movement control body according to the present invention.

According to the present invention, an electrically controlled protuberance (meniscus) of the liquid can be formed, so by using a colored body such as ink as the liquid 200 as described above, the ink-on-demand type multi-nozzle A printer can be formed. This example shows an example of application to such a printer.

In this example, the _{electrodes 1} , ₂ , _.

For the odd numbered electrodes ₁ , ₃ , ... _o-2 , _o , Au or the like is deposited on the substrate surface 11 to a width of about 20 μm, and these voltages, V ₁ , V ₃ ...V _o-4 , V _{o- 2} , V _o is set to zero V and is collectively grounded. On the other hand, even-numbered electrodes ₂ , ₄ , ... _o-3 , _o-1 have a depth of, for example, 20
A _u
etc. are deposited to a thickness of about 1 μm, and an on-voltage V _c and an off-voltage are selectively applied or grounded (zero V).

From the edge 12 side of the substrate surface 11 where the odd-numbered electrodes ₁ , ₃ ... _o-4 , _o-2 , _o are provided, to the edge surface 1
2', a so-called oil barrier 310 as described above repels the liquid material 200 forming the ink.
is applied to prevent the liquid material 200 from leaking out from these parts.

On the edge 13 side, there is a liquid supply body 40 that supplies a liquid 200 forming ink to the substrate surface 11.
Set 0. The installation position is preferably a position that includes the width of the recessed groove 14, that is, at least the maximum electrode width part or the changing part of the supply body 400.
The length from the position corresponding to the edge 401 to the edge 12, that is, the width of the exposed end surface is, for example, about 0.1 to 2 mm.

The liquid supply body 400 is not limited to this example.
In the figure, the liquid material 200 is preferably made of a glass plate or a plastic plate made of cellulose acetate, etc., so that it has the same electroosmotic polarity as the substrate surface 11 (in this example, in the negative electrode direction), and a gap 402 is formed.
This prevents the liquid ink 200 from being refluxed in the interior due to unnecessary electroosmosis. This supply body plate surface and the base material surface 11
The gap 402 between the substrate surface 11 and the electrodes 1 and ₂ in the recessed groove 14 is made to be a parallel gap of, for example, about 50 to 100 μm, and the side plate on the edge 13 side is coated with a leakage prevention agent 320 made of plastic adhesive or _{the like.} … _o-1 ,
_o Liquid material 20 sealed to the surface and directed to the edge 13 side
Prevent the outflow of 0. A liquid material 200 forming ink is inserted into the gap 402 through a thin tube 410.
is supplied from the outside, and the supply pressure is equal to the gap 40
2, the pressure is selected to be appropriately low enough to seep into the substrate surface 11 and the depressed grooves 14.

Thus, the electrode gap between the odd-numbered electrodes 1, 3, ... _o-2 , _o and the even-numbered electrodes ₂ , ₄ ... _o-3 , _o-1 is as narrow as about 40 μm at the edge 401, and at the edge 12. The closer you get, the wider it becomes, about 125 to 1 at the edge 12.
It is about 3 times wider at 30 μm.

Since there is no potential difference between the even-numbered electrode _{o-5 ,} where V _{o-5 =} O ^v , and the odd-numbered electrodes o-4 _{and o-6} on both sides (V _o-4 = V _o-6 = O ^v ), the liquid material 200 Electroosmosis does not occur, and no liquid protuberance occurs at the electrode tip _o-5 '.

However, by chance, like electrode _o-1, for example, V _o-1 =-
When an on-voltage V _c of about 150V is applied, electroosmosis 20 of the liquid 200 occurs from the adjacent odd-numbered electrodes _o and _o-2 (V _o =V _o-2 =O ^v ) through the base material surface 11.
1 and concentrated in the depressed groove 14, and the electrode tip _o-
A movement 202 of the liquid body 200 in the ₁ ' direction occurs.
Due to the presence of the oil barrier 310, the liquid 200 does not wet the edge surface 12' and forms a protrusion (so-called meniscus) 210 of the liquid 200 protruding from the edge surface 12'.

On the other hand, like the even number electrode _o-3 , for example, V _o-3 = +
When an off-voltage V _A of about 150 ^V is applied,
By chance, electroosmosis 202' occurs from the electrode _o-3 side to the odd-numbered electrodes _{o-2 and o-4} , and therefore the liquid 200 moves as indicated by the arrow 201' within the depressed groove 14.
The protrusion 210 as exemplified at the electrode tip _o-1 ' disappears, and a liquid-absent part 211 is created at the electrode tip _o-3 '.

The oil barrier 310 is applied in the form of a thin strip with a width of about 100 to 200 μm, for example, to the odd-numbered electrode tips _o-2 ' _{and o-4} ' to repel the liquid material 200, so that the protrusion 210 cannot be formed.

In this way, a recording medium 500 such as paper is provided at a distance of, for example, about 200 μm from the edge surface 12', a counter electrode 600 is provided on the back side of the recording medium 500, and a counter electrode 600 is provided with a ,
Unlike the conventional method, the on-voltage V _c is applied by simply applying a bias without modulating the high voltage V _H that is sufficient to cause the liquid material 200 to fly from the raised portion 210 by Coulomb force. Ink is ejected from the tips of the even-numbered electrodes, and so-called ink adhesion 220 can be selectively caused on the surface of the recording medium 500. There is a raised portion 210 at the tip of the electrode held at the off-voltage V _A or zero V.
Since there is no ink deposit 220, no ink deposition 220 can occur. Since the ink adhesion density depends on the size of the raised portion 210, it can be changed by amplitude modulating, pulse width modulating, or even pulse width amplitude modulating the on-voltage _Vc , making it possible to record ink with halftones. .

The polarity of the bias high voltage V _H can be either positive or negative, but if it is selected to have the same polarity as the on-voltage V _A , stable ink recording can be performed at a lower voltage.

This is due to the on-state voltage V _c of the liquid material 200 in principle.
This is due to the fact that they are charged with opposite polarity, and in the above example, the potential difference between V _H and V _c is, for example, 1.5 kV.
It is desirable to select one of the above values, and under the above-mentioned operating conditions, for example, V _H is preferably about -1.7 kv to -2.0 kv.

In this way, the on-voltage V _c modulated to the even-numbered electrodes ₂ , ₄ ... _o-3 , _o-1 and the constant off-voltage V _A (including zero V) are selectively controlled via the switch circuit 2. the recording medium 5 in synchronization with this voltage application.
By moving 00 in the direction of arrow 501, ink recording of characters, figures, and even halftone images can be performed.

FIG. 4 is a diagram showing a perspective partial structure and power supply system of still another embodiment of the liquid material electrical movement control device according to the present invention.

The example is the odd numbered electrodes 1, 3, ... _o-
2 , _o are also installed in the depressed groove 14 in the same way as the even numbered electrodes 2, 4, ... _o-3 , _o-1 , and the number of recording electrodes per unit length that participates in ink recording is substantially increased. The recording resolution has been improved, and the dimensions of electrodes ₁ , ₂ ...
The structure is the same except that the arrangement pitch of _o-1 and _o is selected to be, for example, about 400 μm. In this example, by improving the operation method, the odd-numbered tip
₁ ′, ₃ ′... _o-2 ′, _o ′ across the base material surface 1
The oil barrier provided on 1 is removed and an oil barrier 310 is applied only on the edge surface 12'.

In addition, the operation of the outermost electrodes ₁ and _o is stabilized, and the other electrodes ₂ and ₃ ... _o-1
2 , ₃ ... _o-1 so that it operates under the same conditions as
Electrodes ₁ ,
Auxiliary electrodes A ₁ and A ₂ are provided on the base material surface 11 using a metal vapor deposition film or the like on the outside of _{the electrode} . In addition, auxiliary electrodes A ₁ , A ₂
Similarly to the case of the other electrodes 1, 2, . A fixed bias V _B having the same polarity and amplitude as the on-voltage V _A is applied to the auxiliary electrodes A ₁ and A ₂ .

The voltage applied to electrodes ₁ , ₂ ... _o-1 , _o is as follows:
The modulation signal voltage V _c ' is selectively applied while the off-voltage V _A is applied to at least each adjacent electrode.

Here, the modulation signal voltage V _c ' is an off-voltage V _A with a constant amplitude including zero V when ink recording is not performed, and
It includes an on-voltage V _c when ink recording is performed by modulating an input signal.

In this example, an off-voltage V A with a constant amplitude and a modulation signal voltage V _{c '} are alternately applied to the odd-numbered electrodes 1, 3 _{... o- 2} , _o and the even-numbered electrodes 2, 4... o-3, o _- 1. A case of line-sequential recording in which each line is recorded with ink by so-called double writing is exemplified.

In the state shown in the figure, the voltages applied to the odd numbered electrodes are V ₁ and V ₃
...V _o-2 , V _o is modulated signal voltage V _c ′ (i.e. V _A
or V _c ), even numbered electrodes ₂ , ₄ ... _o-3 ,
This is the moment when the off-voltage V _A is applied to _o-1 .

For example, a modulation signal voltage V _c ′ consisting of an off voltage of _{V 1 =} V _c ′=V _A is applied to electrode 1, but an off voltage of V ₂ =V _A is applied to the adjacent even-numbered electrode ₂ .
Furthermore, a fixed bias V _B = V _A is applied to the auxiliary electrode A ₀ , and from the relationship V ₁ = V ₂ = V _A , the liquid material 2
Electroosmosis of 00 barrel ink, therefore electrode tip
₁ ′ and ₂ ′, and A ₁ ′ are the raised portions 21 of the liquid material 200.
0 does not occur, and adhesion 220 of liquid ink as shown in FIG. 3 does not occur.

On the other hand, the odd-numbered electrode _o-2 is turned on and voltage V _c is applied as modulation signal voltage V _c ′ (V _o-2 = V _c ′ = V _c )
Then, the even-numbered electrode _o-3 on both sides (V _o-3 =
Electroosmosis 201 from V _A ), _o-1 (V _o-1 = V _A ),
201' causes extrusion 202 of the liquid 200 in the depressed groove 14 on the electrode _o-2 , and a protrusion 210 is generated at the tip of the electrode _o-2 ', forming ink as shown in Fig. 3. A deposit 220 of the liquid 200 is obtained.

Regarding the odd numbered electrode _o where V _o = V _c ′ = V _c , the auxiliary electrode A ₂ (V _B = V _A ) is used as one adjacent electrode.
is located, so it operates in exactly the same way, and the raised portion 21
yields 0.

Even numbered electrodes V _o-3 (V _o-3 = V _A ), _o-1 (V _o-1 =
In V _A ), the electroosmosis 201, 201' causes the liquid 200 to move as indicated by the arrow 201,
A liquid-absent portion 211 is generated at each electrode tip _o-3 ', _o-1 ', and the above-mentioned ink adhesion 220 does not occur.

Thus, in the above operation, odd numbered electrodes ₁ ,
₃ ... _o-2 , modulation signal voltage applied to _o
Ink adhesion 220 is formed on the recording medium 500 with a density corresponding to V _c ', and the even numbered electrodes ₂ , ₄ ... _o-
Ink adhesion 220 does not occur on _{the 3} , _{o-1 and} auxiliary electrodes A1 and _A2 .

At the next moment, odd numbered electrodes ₁ , ₃ ... _o-2 , _o
Apply off-voltage V _A to even numbered electrodes ₂ , ₄ ...
... When a modulation signal voltage V _c ′ is applied to _o-3 and _o-1 , ink adhesion 220 corresponding to each V _c ′ is generated on the even numbered electrode portions, and in this way, by two time-division driving, a line is drawn. If the recording medium 500 is fed in synchronization with this ink recording, characters, figures, and images can be recorded in line sequentially in ink.

Note that the auxiliary electrodes A ₁ and A ₂ are not limited to this example, but also in other examples, in terms of manufacturing technology.
Array electrodes ₁ , ₂ ... _o-1 , accommodated in 4
It can be substituted by using the outermost electrodes ₁ and _o of the electrodes 1 _{and 2} and applying a fixed bias V _B thereto.

FIG. 5 is a diagram showing a perspective partial structure and power supply system of another embodiment of the liquid electric movement control device according to the present invention.

In this example, in the electrical movement control element 100 shown in FIG. 4, the liquid material 200 is supplied to the base material surface 11 by a film-like porous dielectric material 410 that has a two-dimensional spread and is permeable to the liquid material 200. liquid 200 for
The electroosmosis is carried out by modulation control using the modulation signal voltage V _c ', and is intended for even more sensitive operation.

The material of the porous dielectric 410 is selected so that the liquid 200 is electro-osmotic in the same polarity as the base material surface 11, that is, in the direction of the negative electrode. porous dielectric 410
For example, the thickness is 40~200μm and the average pore size is 0.1~
A microporous menglen filter of cellulose acetate with a diameter of 8 μm and a porosity of about 60 to 80% is used. One edge thereof is sealed over the base material surface 11 and the recessed groove 14 with a backflow prevention sealing agent 320 as shown in the figure. On the porous dielectric 410, for example, the thickness is
100 to 400 for stainless steel or phosphor bronze plates of about 50 μm
Liquid permeable electrode 42 with mesh-sized holes
Install and fix 0. The liquid 200 is, for example, transferred from a container 440 to a sponge body 43 as shown in the figure.
The porous dielectric material 410 and the gap 411 between the porous dielectric material 410 and the substrate surface 11 are supplied through the electrode 420 using capillary action.

In this manner, the movement control device of this embodiment structurally includes a power supply section K, a backflow prevention section L, a liquid supply modulation section M, and a liquid convergence section N forming an exposed end surface.

In this embodiment as well, as in _FIG .
The case where V _c ' is applied is illustrated, and the liquid permeable electrode 420 is grounded to form a substrate potential.

As shown, odd numbered electrodes ₁ , ₃ ... _o-2 ,
modulation signal voltage V _c ′ including off voltage V _A and on voltage V _c at o, respectively, and even numbered electrodes _{2 , 4} ... _o-3 , _o-1
Off voltage V _A to auxiliary electrode A ₁ , A ₂ bias voltage
When V _B is applied, the liquid permeable electrode 420 facing the odd-numbered electrodes (for example, ₃ , _o in the figure), even-numbered electrodes, and auxiliary electrodes that have the relationship of V _c ′ = V _A To form a negative electrode, a porous acid electric material 4 is formed from these electrode parts in the direction of the electrode 420.
A movement 203' of the liquid 200 occurs through the thickness of 10 mm by suction based on its electroosmosis. In particular, the adjacent even-numbered electrodes (for example, ₁ , _o-2 in the figure) are connected to odd-numbered electrodes (for example, ₂ , _o-2 in the figure) to which an on-voltage of V _c ′ = V _c is applied.
₃ , _o-1 ), there is also the above-mentioned electroosmosis 201' through the base material surface 11 towards its even numbered electrodes, regardless of whether it is the modulation part M or the focusing part N. Therefore, the electrode tips of all the electrodes mentioned above (i.e. A ₁ ′, ₂ ′ in the figure)
₃ ′, _o-3 ′, _o-1 ′, _o ′, A ₂ ′) cannot exist at these electrode tips due to the suction movement 202, and the electrode tips are of course In this way, the liquid-absent portion 211 is effectively formed over almost the entire range of the liquid-converging portion N.

On the other hand, in the odd-numbered electrodes (for example, _{1 and o-2} in the figure) to which the on-voltage V _c is applied as the modulation signal voltage V _c ′, the adjacent auxiliary electrode (A ₁ ) and the even-numbered electrodes ( ₂ , o-2)
_o-3 , _o-1 )) In addition to the electroosmotic concentration 201 of the liquid 200 from the electrode 420 side through the porous dielectric 410, the electrode tip _o-2 Due to the forced extrusion 202 of the liquid material 200 towards ', and the electroosmotic concentration 201 on the base material surface 11 located within the convergence part N, the depression groove 14 and the electrode tip _o-
A liquid raised portion 210 is effectively formed at ₂ '.

Therefore, using the Coulomb force flight method as shown in FIG. 4 or as shown in FIG.
The contact transfer method in which V _c ' is brought into contact with the liquid material 220 selectively provides good liquid adhesion 220 corresponding to V c '.

In this way, by selectively applying the modulation signal voltage V _c ' to the odd and even electrodes in a time-division manner and using colored ink as the liquid material 200, an ink printer operating at a low voltage can be constructed.

Although installation of an oil barrier 310 on the edge surface 12' as shown in FIG. 4 is effective in this example as well, it can be omitted as shown in FIG. 5 if the contact transfer method is used.

As in this embodiment, an ink printer device that modulates the supply of liquid 200 by providing a porous dielectric 410 and a liquid permeable electrode ₄₂₀ has already been proposed by the present inventor _. ... _o-1 ,
Unlike the present invention, the electrode width W and the electrode gap G of _o are constant.

Therefore, the extrusion movement 202 and suction movement 202' of the liquid based on the change in the electrode gap G field as described above are performed.
The formation of the raised portion 210 and the liquid-absent portion 211 at the tip of the electrode is due to the liquid 200 staining the liquid converging portion N due to inertia heat based on the electroosmosis 203, 203' through the porous dielectric 410. The main effects were the pulling effect on the liquid supply modulating section M due to the dispensing effect and surface tension.

Therefore, the width of the liquid material convergence part N needs to be narrow, about 50 to 75 μm, and in high-speed operation, the movement 202, 20 of the liquid material 200 in the convergence part N is necessary.
2' could no longer be supported, and high-speed operation was difficult.

However, according to the present application, since forced liquid movement 202, 202' is added based on the above-mentioned electroosmosis 201, 201' due to a change in the electrode gap G, the width of the focusing part N is also set to be as wide as 100 μm or more. It is also advantageous for high-speed operation.

Note that the width of the liquid supply modulation section M is normally selected to be appropriately wide, such as 20 mm or more.

FIG. 6 is a perspective partial structural view of one embodiment of the electrical movement control device for a liquid according to the present invention, and FIG. 7 is a perspective partial structural view of another embodiment.

Generally, when colored ink is used as the liquid material 200 and the apparatus shown in FIG. 5 is used as an ink printer, the recording resolution depends on the number of arranged electrodes per unit length. In order to improve this recording resolution, it is necessary to narrow the arrangement pitch of the array electrodes. If the array pitch is narrowed, the degree of change in the electrode gap G and the electrode width W in the direction of extension of the array electrodes cannot be adjusted to a large extent. The required movement in the liquid convergence section N is large and difficult to achieve. 6 and 7 are intended to improve the device shown in FIG. 5 by taking the device shown in FIG. 5 as an example, and this idea is also applied to the devices shown in FIGS. 3 and 4.

In FIGS. 6 and 7, the recessed groove 14 accommodating the electrode _o-3 ... _o has a constant array pitch Po and width Wo in the liquid supply modulation section M.
Therefore, the width W of the electrode _o-3 ... _o and the electrode gap G are also constant.

However, the depression groove 14 in the liquid convergence part N
Although the pitch Po remains unchanged, WWo′ becomes continuously narrower toward the edge 12 in FIG. 6, and becomes narrower continuously with steps in FIG.

Therefore, the electrode _o-3 in the liquid convergence part N... _o
The electrode width W and the electrode gap G become continuously narrower and wider toward the edge 12 in FIG. 6, and become discontinuously narrower and wider with a step in FIG. 7, respectively.

In this way, if the changes in the electrode gap G and the electrode width W are limited to the exposed end face, that is, within the liquid convergence part N, the rate of change in G and W per unit length in this part can be changed to the electrode _o-3. . . _. Therefore, even if the arrangement pitch of the depression grooves 14 is narrow, it can be made large, and the movement 202, 202' of the liquid material 200 in the electroosmosis 201, 201' described above in the focusing part N can be carried out more effectively. The above-mentioned difficulties in principle in forming the raised portion 210 and the liquid-free portion 211 are further improved.

Note that, as shown in FIG. 6, if the depth of the depressed groove 14' is made shallower toward the edge 12, the above-mentioned movement 202,
202' has an excellent effect that is further promoted.

In this embodiment, the electrodes _{o-3 .}

In addition, in the above description, it is clear that the liquid material 200 is not limited to colored ink, and other non-colored materials can be used as well.

As detailed above, the present invention is an apparatus for controlling the electrical movement of a liquid by providing a plurality of electrodes on the surface of a solid dielectric base material, changing the gap between these electrodes, and utilizing the electroosmosis. , electrical movement control of various liquids, and by applying these, high-performance ink printers such as multi-nozzle, ink-on-demand, and low-voltage modulation operation types can be realized.
Its industrial effects are significant.

[Brief explanation of the drawing]

FIGS. 1a, b, and c are diagrams showing a perspective partial structure and power supply system of an embodiment of the electrical movement control device for liquid material according to the present invention, and FIG. 2 is a diagram showing the electrical movement of liquid material according to the present invention. FIG. 3 is a partial structural diagram of another embodiment of the control device; FIG. 3 is a diagram showing a perspective partial structure and power supply system of still another embodiment of the liquid electrical movement control device according to the present invention; FIG. FIG. 5 is a diagram showing a perspective partial structure and a power supply system of another embodiment of the electrical movement control device for a liquid according to the present invention, and FIG. A diagram showing a perspective partial structure and a power supply method, FIG. 6 is a perspective partial structural diagram of an embodiment of the electrical movement control device for a liquid according to the present invention, and FIG. 7 is a diagram showing the electric movement of a liquid according to the present invention. FIG. 6 is a perspective partial structural view of another embodiment of the control device. 1...Signal voltage circuit, 2...Switch circuit, 1
0... Dielectric base material, 11... Base material surface, 12,1
3... Edge, 14... Recessed groove, 100... Electric movement control element, 200... Liquid, 201, 20
1', 202, 202'...Liquid material movement by electroosmosis, 210...Liquid material protrusion, 211...Liquid material absent area, 220...Liquid material adhesion, 310...
Oil barrier, 320...Sealant to prevent leakage...
400...Liquid supply body, 410...Porous body,
420... Liquid permeable electrode, 500... Recording medium, 600... Counter electrode, 610... Pressure roller, ₁ , ₂ ... _o-1 , _o , _A1 , _A2 ... Electrode,
V ₁ , V ₂ ...V _o-1 , V _o , V _A , V _B , V _c , V _c ′... Voltage.

Claims (1)

[Claims] 1. A plurality of electrodes provided on a plane of a fixed dielectric base material, insulated from each other, and extending to an edge of the base material, such that the gap between adjacent electrodes widens toward the edge. the edge of the substrate by disposing an electroosmotic liquid on the substrate and controlling the movement of the liquid along the electrodes in response to a voltage applied between the adjacent electrodes. An electrical liquid movement control device that controls the amount of liquid exposed from the end.