JPS58212960A - Ink recording head - Google Patents

Abstract

PURPOSE:To increase the pressure-sending speed of ink by using a system in which the face of a dielectric base plate is bonded in a sealed manner with the surface of a porous material by leaving an aperture, e.g., a groove through which ink moves, in a printer in which ink is moved and printed by utilizing electric osmosis. CONSTITUTION:A large number of parallel grooves 6 are provided on a dielectric base plate 1, and recording electrodes 5 are set on the bottoms of each groove 6. An ink-permeable electrode 3 is then provided on the base plate 1 through a porous material 2. A voltage is applied between such a recording electrode 5 and the ink-permeable electrode 3, and thereby ink is moved to one end of the grooves 6 by electric osmosis and recorded. In such a printer, the surface 1' of the dielectric base plate 1 including the aperture face 1a between the recording electrodes in an ink amount-modulating portion 8 is bonded with the surface 2' of the porous material 2 with the aid of a sealant 20 having the same polarity as the surface of the porous material 2 and the dielectric base plate 1 in terms of electric osmotic polarity to the ink 4 to be used.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an ink recording head of a recording apparatus that records characters, figures, etc. on recording paper using ink.

A liquid ink permeable electrode is placed on the surface of the dielectric substrate on which the recording electrodes are arranged, with a porous body interposed therebetween, and the liquid ink moves between the surface of the recording electrode and the surface of the porous body. forming possible gaps and utilizing electroosmosis of the liquid ink to the surfaces of the porous body and the dielectric base material,
The present inventor has already proposed an ink recording head in which a recording ink portion for instant recording on a recording medium is formed on the tip end side of a recording electrode.

An example of the configuration of the ink recording head described in item 1- is shown in FIG. In Fig. 1, 1 is a plate-shaped dielectric substrate made of a glass plate made of cellulose acetate, polyimide, phenol resin, etc., a glass plate, a porcelain plate made of alumina, etc., and 2 is a plate-shaped dielectric substrate made of cellulose acetate, cellulose nitrate, etc. plastic materials,
It is made of glass material, porcelain material such as alumina, etc., and has a thickness of 20 to 200 μm and has holes with an average pore diameter and average gap of about 0.1 to 10 μm and minute gaps that penetrate continuously in the thickness direction. 3 is a membrane or plate-like porous body of
An electrode that transmits oil-based or water-based liquid ink 4 supplied from the outside.
A mesoelectrode is formed by drilling holes at a density of about 00 meshes (ie, 100 to 400 meshes).

The porous body 2 is lightly pressed against the dielectric substrate surface 1' via the liquid ink permeable electrode 3.

6 is, for example, Cr or N1-Cr gold alloy 0.1 to 0.3
The recording electrode is a recording electrode in which P is formed by thinly vapor-depositing the prn culm, and then depositing Au or the like thereon to a thickness of about 1 to 3 μflr.

This recording electrode 5 has this electrode surface 5' and the porous body surface 2.
In order to form a gap between which the liquid ink 4 can move, for example, a depth d-10 is formed on the surface 1' of the dielectric substrate 1 by photo-etching, cutting, or molding.
It is deposited in the groove 6 with a width αP of ~iooμm (however, α is less than 1).

For example, P is selected to be 125 to 61.25 pm (that is, 8 to 16 pm), and α is selected to be approximately 0.2 to 0.8.

One edge 2'' of the porous body 2 is connected to the edge KA of the dielectric substrate 1.
The ink convergence portion 7 is formed at a position inside about M=50 to 200 μm from i1″.

One edge 3' of the liquid ink-permeable electrode 3 is 50 to 100 mm lower than the edge 2'' of the porous body 2 to prevent dielectric breakdown.
Position it about μ711 inside.

The other edge 2#7 side of the porous body 2 seals the porous body surface 2' with the dielectric substrate surface 1' and the surface of the recording electrode 5 in the groove 6 by the arrival agent 8', and the liquid ink Prevent the leakage of 4.

As illustrated in FIG. 1, the liquid ink 4 is supplied from the outside to the recording head 100 by dropping the ink onto the liquid ink permeable electrode 3 and permeating and diffusing the porous body 20 by capillary action. 08 is an ink amount modulating section. For example, the length L is 2
Ink recording 11 on a recording medium 10 such as paper is performed by, for example, placing the recording medium 10 in contact with the dielectric resonance edge 1', and moving the recording medium 10 as indicated by the arrow 12 in FIG. Do it by moving it.

The ink recording head 100 is driven as shown in FIG.
An off-voltage V with a constant amplitude is alternately applied to the liquid ink permeable electrode 3 and the odd-numbered and even-numbered recording electrodes 6. ff (however, amplitude 1.ff +≧0) and a recording voltage Vs modulated by an input signal for ink recording are added, and these are alternately switched to record one line divided into two.

The liquid ink 4 may be formed by dissolving ionic dyes or direct dyes in an aqueous solvent such as water or alcohol, or by dissolving an ionic dye or direct dye in an aqueous solvent such as water or alcohol, or by dissolving a non-aqueous ink such as xylene or γ-methac IJO xyfurobyltrimethoxysilane. An oil-based ink is formed by dissolving an oil-soluble dye or the like in a solvent, and if necessary, a surfactant, a charge control agent, and a vehicle material are dissolved therein to make the porous body 2 electroosmotic. configured.

These inks 4 preferably have a resistivity of 106 Ω or less, a viscosity of 10 cp or less, and a surface tension of 16 to
It has a value of about 40 dyne/crn.

From the perspective of dielectric strength, the specific resistance is 107Ω or more.
It is preferable to use a neutral ink.

The electroosmotic polarity of the liquid ink 4 is in the negative potential direction.

Materials can be selected in either direction of positive potential, but in the figure,
A case where electroosmosis occurs in the negative potential direction is illustrated.

The amplitude 1vs1 of the recording voltage vs1 is 0 to 1■on1 (however, I
It has a value in the range of VOnl>IVoHl), and the polarity of Vs is ■. The polarity is opposite to ff, and Vs is ■. Since it is superimposed on ff, Vs is V. ff to V. It has a value in the range n.

Off voltage ■. ff, due to electroosmosis in the thickness direction of the porous body 2, the liquid ink 4 on the recording electrode surface 5' passes through the porous body 2 to the liquid ink permeable electrode 3, as shown by the arrow 13 in the figure.
In this example, a positive voltage is applied to ① off.

On the other hand, the recording voltage ■s has a polarity that is osmotic and pressure-transferred from the electrode 3 side through the porous body 2 to the recording electrode surface 5' side as shown by the arrow 14 in FIG. In this example, a negative voltage is applied to Vs.

In FIG. 1, on-voltage V. ff, recording voltage ■5=v
In the part where off is applied, the liquid ink 4 located at the recording electrode tip 5'' travels along the recording electrode surface 6' in the groove 6 and is focused as shown by the solid arrow 16 due to the suction action as shown by the arrow 13. Section 7. Ink shading modulation section 8. Since the ink is sucked up to the electrode 3 side through the porous body 2, no ink adhesion 11 can occur on the recording medium 10.

However, vs-■. In the part of the recording electrode 5 to which a negative voltage n is applied, the recording electrode in the groove 6 is moved by osmotic pressure feeding as shown by the arrow 14 in accordance with the voltage amplitude or pulse width, as shown by the solid arrow 16, contrary to the above. The ink amount modulator 8. The recording electrode tip 5 passes through the ink focusing section 7.
Ink 4 is supplied to the ' side and controlled liquid ink section 4
' is formed, resulting in an ink deposit 11 on the recording medium 10.

In this case, if the electroosmotic polarity of the dielectric substrate 1° and therefore the substrate surface 1' with respect to the liquid ink 4 is selected to be the same as that of the porous body 2, that is, in the negative potential direction in this example, the recording electrode in the ink amount modulating section 8 In the bonding gap 9 between the substrate surface 1' including the gap surface 1a and the porous body surface 1', a potential difference V
s-V. ff, Vs is
-V. The off-voltage V of the liquid ink 4 due to electroosmosis in the thickness direction as shown by the arrow 14 corresponding to 0. Diffusion 19 of the ff application to the recording electrodes on both sides can be prevented.

Therefore, the osmotic ink as indicated by the arrow 16 corresponding to vs=von is effectively pumped around the groove 6 toward the recording electrode tip 6'' side, that is, toward the ink convergence section 7 side.

In the ink focusing unit 7, this pressure-fed liquid ink is collected in the grooves 7 due to the focusing action by electroosmosis in the surface direction as shown by the arrow 18 on the dielectric substrate surface 1b between the recording electrodes 6 corresponding to the potential difference 5-voff. Since the ink is focused inward, a point-like ink adhesion 11 is formed corresponding to the tip cross section of the recording electrode tip 6''.
can be obtained.

Therefore, the off-voltage V is applied to the odd-numbered and even-numbered recording electrodes 5. f
If the recording voltage Vs corresponding to f is applied alternately and switched alternately, and the recording medium 1o is fed in synchronization with this as shown by the arrow 12, a so-called double recording is performed in which the - line is divided into two parts and recorded. Patterns, characters, or drawing lines can be recorded in the order of dividing lines.

In general, the electroosmotic degree U of the liquid ink 4 can have a value of about 10 to 10 crn/V, sea by appropriately selecting the material.

Now ■. The electric field strength in the thickness direction of the porous membrane 2 related to ff and vs is El, and the electric field strength E2 between recording electrodes related to the recording electrode voltage v8-voff in the bonding gap 9 and ink focusing section 7 is, for example, 2×104v. /cIn, P = I Q tyn, 0. = O,
'5.

d = 2 x 10 crn, L = 2 cm
, the respective electroosmotic degrees are both 10-6 to 1O-4cy1
．． /V, Sec, and the diffusion 19 due to ink pressure feeding as shown by the arrow 14°160 is assumed, and the time τ1 required to obtain the moving length t-1o-2Crn of the liquid ink 4 at the recording electrode tip 5'' is approximately expressed as: When calculated, the movement of the liquid ink 4 within the porous body 2 is G within the groove 6 of the modulating section 8.
-LZd Yu 103 times speed converted, τ1 Yu 5X10 ~
This shows that extremely high-speed recording is possible at 5 x 10 sec. On the other hand, the recording electrode gap 1 in the modulation section 8 and the focusing section 7
The time τ2 required to focus ink a, 1b, that is, P(1-α)=5×10α as shown by arrows 17' and 18, is 2.5×10 to 2.5×10 sec.
So, τ2. 〉τ1.

Therefore, the electroosmotic degree U is 10 ca/V,
If it is as low as sea, U is 10-5 to 1O
-46d/V, sec, the ink velocity V2t/τ1 in the groove 6 is 2×102cm/5ecL-
2X 106 (7F+/Sec), which increases the flow resistance of the movement 16 of the liquid ink 4 in the groove 6.

Therefore, the pressure of the liquid ink 4 in the bonding gap 9 caused by the osmotic pressure feeding 14 momentarily becomes abnormally high, and depending on the surface direction electroosmosis 17, the pressure of the liquid ink 4 becomes abnormally high. Adjacent recording electrode 6 to which ff is applied
Ink diffusion 19 to the sides becomes unstoppable.

Therefore, it has been found that this ink diffusion 19 causes a problem in that it is difficult to obtain the desired speed V in the ink pressure feeding 16.

In view of the above, an object of the present invention is to propose an improved ink recording head that solves the above problems.

In the ink recording head according to the present invention, in the above-mentioned ink recording head, the surface of the recording electrode is formed with a gap such as a groove in which the liquid ink can move, and the surface of the dielectric substrate is connected to the surface of the dielectric substrate. The surface of the porous body facing the surface is sealed.

By doing so, the arrangement gaps between the recording electrodes are sealed, the above-mentioned ink diffusion is prevented, and the operational performance can be improved.

Hereinafter, aspects of the present invention will be described in detail, mainly taking the ink recording head 100 of FIG. 1 as an example. - FIG. 2 is a perspective partial structural view of an improved ink recording head according to the present invention.

In FIG. 2, 2o is a sealing agent, which is attached to the dielectric substrate surface 1' including the recording electrode gap surface 1a in the ink amount modulating section 8.
and the corresponding porous body surface 2' are bonded together.

In this way, the ink diffusion 19 explained in FIG.
In the area of the recording electrode 5, the applied force is efficiently pumped as shown by the arrow 16 within the groove 6 forming the gap, forming a controlled liquid ink portion 4' at the electrode tip 5'', and ink is transferred at high speed. On the other hand, in the portion of the recording electrode 5 to which the on-voltage V.ff 1 recording voltage v8-■.ff is applied, the ink-attached portion of the recording electrode 5 due to the ink diffusion 19 is Since unnecessary inflow of the liquid ink 4 is prevented, the arrow 1 can be efficiently drawn from the electrode tip 5''.
5, and a dotted ink deposit 11 with high resolution is obtained.

Note that it is desirable that the electroosmotic polarity of the sealing agent 20 with respect to the liquid ink 4 used is the same as that of the surfaces of the porous body 2 and the dielectric substrate 1 (in this example, in the negative potential direction).

When sealing with the sealing agent 20, a part of the arrival agent 20 is impregnated into the porous body 2, so if there is an electroosmotic relationship with the opposite polarity to the above, the liquid ink 4 will move in the opposite direction in this part. electroosmosis, making the operation unstable and significantly reducing the ink recording speed.

Regardless of the iodine of the sealant 20, porous body 2, or dielectric substrate 1, it is generally convenient to use a so-called adhesive made of plastic. The porous body 2 and dielectric substrate 1 materials are
When the material is glass or porcelain, glass sealing can be used.

In view of the electroosmotic polarity described above, it is recommended that the sealant 2 be made of the same type of material as the porous body 2.

For example, when the dielectric substrate 1 is made of glass or ceramic material and the porous body 2 is made of cellulose acetate-based material, it is preferable to use a sealing agent 20 of cellulose acetate, and the porous body 2 is made of glass or When the material is porcelain, a glass-based sealant 2 is also added.
0 is recommended.

FIG. 3 is a perspective partial structural view of another embodiment of the ink recording head according to the present invention.

In this embodiment, in the structure shown in FIG. 2, in the groove 6 forming the gap, the width of the groove 6' in the ink amount modulating section 8 is narrowed to 6'' from the middle toward the ink converging section 7. For example, when the arrangement pitch P of the recording electrodes 5 is 12511 m, the width of the groove 6' is 80 pnt, and the width of the groove 6'' is 20 μm.
71I, osmotic pressure delivery 16. Not only can the ink speed θ of the suction 15 be made faster than in the case of FIG. be. The length of the groove 6' is not limited to this example,
For example, the length within the modulation section 8 is preferably within L/2 so that the liquid ink permeable electrode 3 is located above it.

Note that the depth d of the grooves 6' and 6'' may be the same or may be configured to be slightly different, but for stable operation, the depth d should be the same or
It is desirable that the depth of the groove be somewhat shallower, or 6".Selection of the depth of the groove in this manner is applicable not only to this embodiment but also to all embodiments described herein.

FIG. 4 is a perspective partial structural view of another embodiment of the ink recording head according to the present invention and an ink recording apparatus using the same.

In this embodiment, there is no ink converging portion as shown in FIG. 3, and the edge 2'' of the porous body 2 and the edge 1'' of the dielectric substrate are aligned. By narrowing the width of the groove 6″ on the edge 1″ side,
(2) By the osmotic pressure feeding 14 and 16 corresponding to S ``''''on, ink jet 16' can be generated from the recording electrode tip 5'' by the electroosmotic pressure.

Therefore, by setting the recording medium 10 at a distance of, for example, about 200 μ7/l from the edge 1', ink jet recording becomes possible. In this case, for more stable operation, the voltage vs. Von that enables the osmotic pressure feeding of the ink 4 -14, 16.
A high voltage vH of the same polarity (in this example, a negative potential with respect to the liquid ink permeable electrode 3) is applied via the back electrode 21,
For example, if the voltage vH is selected to be larger than the amplitude of V, the ink flight 16' is promoted corresponding to the amplitude. If the amplitude is selected to be smaller than the amplitude of n, or the opposite polarity (positive potential in this example) is selected, the ink jet 16' can be suppressed.

Thus, by adjusting vH, there is an advantage that the ink deposition 11 can be adjusted and modulated.

■The amplitude of oil-based ink (for example, 1
08Ω (about 7)), the electric field strength in the thickness direction of the porous body 2 E1. The electric field strength E2' between the recording electrodes 6 can be selected to be about 3 x 10' V/c1n at maximum, and when the thickness of the porous body 2 is 150 μm and the recording electrode arrangement is 125 μnt, vS-■. f(is Ms o V
It can be selected according to the degree. Therefore, in order to promote ink flying 16', it is desirable to select a negative voltage with an amplitude of 450 square meters or more as vH.

Note that recording by the above-mentioned ink jet 16' is performed when the electroosmotic degree U and the length L of the modulating section 8 are appropriately selected.
Groove 6. Even if you choose the same width for 6' and 6'', it's still a trench.
This is also possible in the embodiment shown in Fig. 3.Although the widths of the grooves 6' and 6' change discontinuously in Figs. In the modification of the present invention and 1, if the electroosmotic degree of the liquid ink 4 is appropriately small as shown in FIGS. 3 and 4, , it can be used without sealing with the sealing agent 20 as in the conventional case.However, the ink converging section 7 may or may not be provided.

The same applies to the following examples.

FIG. 5 shows 1. Ink recording according to the present invention. FIG. 7 is a vertical cross-sectional structural view of another embodiment of the board.

In the embodiment described above, the groove forming the gap is a dielectric layer [1.
Although it is provided on the substrate side in this example, it can also be provided on the porous body 2 side as shown in 6o in the figure.

This @60 can be formed by hot embossing when the porous body 2 is an old plastic material, and by molding, etching, or machining when it is made of glass or porcelain material.

This embodiment is useful when performing ink jet recording without providing an ink convergence section, as shown in FIG.

FIG. 6 is a longitudinal cross-sectional structural view of still another embodiment of the ink recording head according to the present invention.

In this embodiment, the groove 61 forming the gap is formed by the porous body 2.
In the dielectric substrate 1, a strip-shaped dielectric spacer 22 having at least the same electroosmotic polarity as that of the porous body 2 is attached to the porous body 2 using a sealing agent 20' having the same electroosmotic polarity as described above. The mass body 2 and the dielectric substrate 1 are interposed and sealed. This configuration is the case where the ink converging section 7 is not provided as shown in FIG. 4, but the second. As shown in FIG.
This extended portion is coated with sealant 2 on dielectric substrate 1.
It can be constructed by bonding one side of it with 0'.

The configurations of the above embodiments can be combined as appropriate.

As described above, the present invention has a configuration in which the recording electrode arrangement gap is sealed behind the throat of ink recording using electroosmotic phenomenon, and the high-speed and stable operation of ink recording is achieved.
Ink flying recording can also be effectively realized, the effect is extremely remarkable, and the contribution to industry is significant.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a conventional ink recording gutter and an ink recording device using the gutter, and FIG. 2 is an ink recording head in an embodiment of the present invention improved in relation to FIG. 1. , a perspective view of an ink recording device using this, FIG. 3 is a perspective view of an embodiment of the same place and an ink recording device using this, and FIG. 4 is a perspective view of another embodiment and an ink recording device using this. A perspective view of the device, FIG. 6 shows ins 1...dielectric substrate, 2...porous body, in one embodiment of the present invention.
3... Liquid ink permeable electrode, 4... Liquid ink, 5... Recording electrode, 6.6', 60.
61...Groove forming a gap, 7...Ink convergence section, 8...Ink amount modulation section, 9...
...Joining gap, 1o...Recording medium, 11...
...Ink adhesion, 20,20'...Sealing agent,
22...Spacer, 10o...Ink recording head. Name of agent: Patent attorney Toshio Nakao (1st person)
figure! ! [Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] A liquid ink permeable electrode is placed on the surface of the dielectric substrate on which the recording electrodes are arranged, with a porous body interposed therebetween, and the liquid ink moves between the surface of the recording electrode and the surface of the porous body. An ink recording head characterized in that a dielectric base material surface located in the arrangement gap of the recording electrodes is sealed to the porous body surface facing the base material surface by forming a possible gap portion.