JPH02286348A - Recorder - Google Patents

Abstract

PURPOSE:To enable a printing material at an amount corresponding to a voltage value applied to discrete electrodes or a voltage-applying time to be put out and to jump in the air by giving an electric field curtain power to the printing material through applying voltage to two separate electrodes arranged with the printing material between in the vicinity of the opening of a nozzle according to a picture image information. CONSTITUTION:When an alternating voltage or pulse voltage is applied to current- carrying electrodes 9, 10 on the basis of a signal from a controller 21, an ink In positioned between the current-carrying electrodes 9, 10 is excited and heated to generate air bubbles 23. Simultaneously, an alternating voltage is applied to the separate electrode 7 of an upper panel 2 and a voltage is applied to the separate electrode 8 of a lower panel 3 according to a picture image information. As a result, an electric charge is injected from the electrode 8 into the ink In so that an electric field curtain is formed between and around the electrodes 7, 8. The ink in receives an electric field curtain power by the injected charge as a trigger to move in the direction of the arrow (a) so that an ink drop In' of a size corresponding to the electric field curtain power and the amount of the injected charge from the electrode 8 is put out and jumps in the air to be recorded on a recording paper 24.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a recording device such as a printer that uses an electric field curtain.

[Prior art]

Conventionally, as one type of recording device, a bubble jet type inkjet printer head in which a heating resistor element is provided near the opening of a nozzle made of an insulating material has been disclosed in Japanese Patent Application Laid-open No. 1983-1999.
This is proposed in Japanese Patent No. 59936.

In this printer head, a bubble is formed in the ink in the nozzle by applying a signal corresponding to image information to the heating resistor element, and based on the change in the volume of the bubble, the ink near the nozzle opening is The liquid is ejected and flies into the air, and is recorded on a recording medium. .

[Problem to be solved by the invention]

However, in the printer head, the ink ejection and
Since flight depends only on changes in the volume of bubbles, it is impossible to eject and fly ink unless the bubbles are formed to a certain size or larger. That is, the ink cannot be ejected or made to fly by applying a small voltage or current, and the control is difficult, resulting in poor gradation.

[Means to solve the problem]

The present invention has been made to solve the above problems,
In the recording device, (i) a nozzle made of an insulating material, (ii) a printing material supplied into the nozzle, and (i) a nozzle made of an insulating material;
ii) at least two individual electrodes disposed on both sides or one side of the printing material in the vicinity of the nozzle opening, and (iv) applying a voltage to the individual electrodes in accordance with image information, (v) applying a force that pushes the printing material near the nozzle opening toward the opening by changing the volume of the printing material within the nozzle; It has a means to do so, and a means to do so.

[Effect]

In the recording apparatus having the above configuration, the printing material inside the nozzle is held in a state where it is pushed toward the opening.

In addition, when a signal corresponding to image information is applied to the individual electrodes by the electric field forming means, an electric field curtain is formed between the individual electrodes, and the printing material near the opening receives a force directed toward the opening, and the printing material passes through the opening. It is ejected and flies into the air.

Here, as mentioned above, the printing material near the opening is in a dynamic state and is in a state where it is easier to eject than the opening, so even if only a small voltage is applied to the individual electrode, the voltage value or the applied An amount of printing material is ejected and sent flying into the air depending on the time.

〔Example〕

Hereinafter, a specific example of a recording apparatus having the above configuration will be described with reference to the accompanying drawings.

A. First embodiment (see Figures 1 to 3) In the figure, l is the print head of the recording device, 2 is the upper panel, and 3 is the lower panel. Both the upper panel 2 and the lower panel 3 are made of an insulating base. It is made of wood. The lower panel 3 has a third
As shown in the figure, a plurality of slits 4 are formed,
By overlapping the upper panel 2 and the lower panel 3, a nozzle 5 is formed corresponding to the slit 4.
An orifice 6 is formed at one end. On the panel 2.3, individual electrodes 7 and 8 are provided facing each other near the orifice 6, and current-carrying electrodes 9 and 10 are installed facing each other on the opposite side of the individual electrodes 7.8 from the orifice 6. It is. Note that the portion of the individual electrode 7 of the upper panel 2 facing the nozzle 5 is covered with an insulating protective film 11. In addition, the outer surfaces of the upper panel 2 and lower panel 3 are double coated with an insulating protection film 12 and an ink-phobic insulating protective film 13.
The insulating protective film 13 (surface layer portion) extends to the tip of the nozzle 5.

In the print head l having the above configuration, ink In is supplied to each nozzle 5 from an ink tank (not shown). As the ink In, a high-resistance ink in which pre-charged charged color particles are dispersed, or a chargeable heat-melting ink is used. This chargeable ink consists of electrons from electrodes,
Various types of ink can be charged by charge injection such as hole ions, induced charging in an electrostatic field, contact charging due to contact with wall materials, electrodes, etc., charging due to polarization inside the ink, charging due to having polar groups, etc. Point.

In the printer head 1 having the above configuration, the control device 2
The current-carrying electrode 9.10 is powered by the power source 22 based on the signal from 1
When an alternating voltage or pulse voltage is applied to the current-carrying electrode 9
．． The ink In located between 1O and 1O is heated by electricity to generate bubbles 23.

Then, an alternating voltage is applied from the alternating type #20 to the individual electrodes 7 on the upper panel 2 in synchronization with the generation of the bubbles 23, and the control device 21 applies an alternating voltage to the individual electrodes 8 on the lower panel 3 in accordance with the image information. A voltage is applied to. As a result, charge is injected from the electrode 8 into the ink In, and an electric field curtain is formed between and around the electrodes 7,8. Note that an electric field curtain refers to an alternating electric field that is unequal in time and space that is formed around a pair of electrodes and between the electrodes when an alternating voltage is applied between the electrodes. The charged substance is subjected to Coulomb repulsion, that is, electric field curtain force. For details, see JP-A-62-11175.
This is explained in Publication No. 4.

That is, the ink In located between the electrodes 7 and 8 is
The injected charge acts as a trigger and receives an electric field curtain force (Coulomb repulsion), causing the ink In located near the orifice 6 to
moves in the direction of arrow a, and an ink drop In' of a size corresponding to the amount of charge injected from the electric field curtainer and electrode 8 is ejected into the air and is recorded on the recording paper 24.

As mentioned above, the expansion of the bubble 23 is synchronized with the application of alternating voltage to the electrode 7.8, and the ink In near the nozzle opening is pressurized by the bubble 23 in the direction of the opening. Even if only a small voltage is applied to the electrode 8, an amount of ink corresponding to the voltage value is ejected and flies. Also, at the same time as the bubble 23 contracts, the ink In receives a force on the side opposite to the orifice 6, so the ink drop
The sharpness of n゛ becomes better.

After one dot worth of ink droplet In' flies, the orifice 6
Ink In is replenished from the rear.

After the ink droplet In' flies, the individual electrode 8 is grounded, and the residual charge in the ink In is erased.

However, if the ink In is charged only by induced charging or internal polarization, grounding is not essential.

Note that when injecting charges into the ink, it is preferable to apply a negative voltage to the individual electrodes 8 because charges of negative polarity generally have faster mobility. Of course, in the case of ink whose physical properties are adjusted to make it easier to move in the direction of positive polarity, a positive voltage is applied.

B. Second Embodiment (See Figures 4 and 5) In the printer head 30 of this embodiment, the upper panel 31 and the lower panel 32 are connected to the printer of the first embodiment.
A nozzle 33 is formed between the panel 31.32 and the orifice 34, and individual electrodes 35.36 are arranged facing each other near the orifice 34 of the panel 31.32.
'ff1 is overturned in 7. The lower panel 3 also has a heating resistor 38 on the opposite side of the individual electrode 36 from the orifice 34.
is the provision. Further, the outer surfaces of the upper panel 2 and the lower panel 3 are double coated with an insulating protective film 39 and an ink-phobic insulating protective film 40, and the outer (surface layer) insulating protective film 40 is coated with a nozzle. It extends to the tip of 33.

The same ink I n as used in the first embodiment is used.

In the printer head 30 described above, the power supply 42 is turned on and off based on the signal from the control device 41, and the heating resistor 3
A voltage is periodically applied to 8. The heating resistor 38 is
42 is turned on and off, and bubbles 44 generated in the ink In in contact with the heating resistor 38 expand and
Shrink. Further, the ink In vibrates according to the expansion and contraction of the bubbles 44.

In this state, an alternating voltage is applied to the electrode 35 of the upper panel 31 from the electric current 43, and when a signal corresponding to the image information is applied from the control device 41 and a charge is injected into the ink In, the electrodes 35 and 36 An electric field curtain is formed between the bubbles
The ink In, which vibrates periodically based on the expansion and contraction of the electrode 44, is further strongly urged toward the orifice side between the electrode 35, 36 and the orifice 34, and becomes ink 711i[n'. Recording paper 45 is ejected and flies into the air.
recorded in

C9 Third Embodiment (See FIG. 6) The printer head 50 of this embodiment also has a plurality of nozzles 53 formed in parallel between the upper panel 51 and the lower panel 52, similar to the printer heads I and 30 described above. and each nozzle 53
Now, an individual electrode 55 and a piezo vibrator 57 are mounted on the upper panel 51.
．． 57, an electrode 56 for charge injection and a piezo vibrator 58, 58 are provided on the lower panel 52, and electrodes 55 and 56,
Piezo vibrators 57 and 58 are opposed to each other. Note that, except for the electrode 56 for charge injection, the electrode 55 and the dew 1 on the nozzle 53 of the piezo vibrator 57, 58 are covered with an ink-philic insulating protective film 59 to prevent them from coming into direct contact with the ink In. It is. Furthermore, is the outside of the orifice 54 ink-phobic insulation? & 60% protection.

In the printer head 50 having the above configuration, the piezo vibrator 57. An alternating voltage is applied to each of the piezoelectric vibrators 57 and 58, and distortion occurs in the piezoelectric vibrators 57 and 58 in accordance with the frequency of the alternating power supply. This distortion becomes vibration and is propagated to the ink In, causing the ink In to vibrate.

In this state, when an alternating voltage is applied to the individual electrodes 55 and a voltage is applied to the charge injection electrode 56 according to the image information, charges are injected into the ink In and an electric field curtain is created between the electrodes 55 and 56. is formed, and the ink in located between the electrodes 55, 56 and the orifice 54 becomes ink droplets and is ejected and flies into the air. Here, as described above, since the ink In is vibrated by the piezo vibrators 57 and 58, it is ejected in response to even a slight voltage signal applied to the electrode 56. Further, the size of the flying ink droplets may be varied by changing the value or application time of the voltage applied to the electrode 56 according to image information, or the electrode 56 may be simply turned on and off. , may be performed by controlling the voltage value of an alternating signal input to the piezo elements 57 and 58.

D. Fourth Embodiment (See FIG. 7) In the printer head 60 of this embodiment, an individual electrode 6 for ink flying is provided on the lower surface near the orifice 64 of the upper panel 61.
5 is attached, and the electrode 65 is connected to an alternating current power source 67 via a switch 66. An individual electrode 68 is buried in the lower panel 62 facing the electrode 65, and the electrode 68 is grounded. Moreover, piezo vibrators 70 and 72 are attached to the rear of the electrodes 65 and 68 of the panels 61 and 62, facing each other, and the piezo vibrators 70 are connected to the power source 71.
The other piezo vibrator 71 is connected to a power source 73.

In the printer controller 60 with the above configuration, the power supply 71
An alternating voltage is applied to the piezoelectric vibrator 70, and vibrations are propagated into the ink In according to the distortion of the piezoelectric vibrator 70.

On the other hand, the switch 66 is turned on or off depending on the presence or absence of image information output from the control device, injecting charges into the ink and forming an electric field curtain between them. In addition, the power source 73 is driven in accordance with image information from the control device, and voltage is applied to the piezo vibrator 72. As a result, vibration is further applied to the ink In, and an ink droplet having a diameter corresponding to the size of the ink In is ejected and flies into the air through the orifice 64, and is recorded on a recording paper (not shown).

E. Fifth Embodiment (See FIGS. 8 and 9) In the printer head 80 of this embodiment, an individual electrode 85 for ink flying is attached to each nozzle 83 near the orifice 84 of the upper panel 81.

On the lower panel 82, an individual electrode 86 for charge injection is attached corresponding to the individual electrode 85. Further, in the lower panel 82, a cantilever section 80 is provided on the side opposite to the orifice 84 of the individual electrode 86, and this section 90 has an electrode 9
2 is facing each other.

The section 90 is made of an electret material, and for example, the upper surface (the surface facing the upper panel 81) of the section 90 is negatively charged, and the lower surface is positively charged.

The outer surfaces of the panels 81 and 82 are doubly protected by an insulating protective film 87 and an ink-phobic insulating protective film 88, and the electrodes 85 of the upper panel 81 are protected by an insulating protective film 89.

In the printer controller 80 having the above configuration, the alternating power supply 9
When an alternating voltage is applied to the electrode 92 from 3, the section 90 vibrates, and the vibration is propagated to the ink In within the nozzle 83. Further, when an alternating voltage is applied to the individual electrodes 85 from the alternating power supply 91 and a signal corresponding to image information is applied from the control device 94 to the charge injection electrode 86, the ink In
An electric field curtain is formed between the electrodes 85 and 86, and the ink In located between the electrodes 85. and flew into the air, recording medium 9
Recorded in 5. Note that since the ink In is subjected to the vibration of the section 90, even if a slight electric field curtain is generated, the ink In is easily turned into an ink droplet In' and is ejected and flies.

F. Sixth Embodiment (See Figure 1O) In the printer head 100 of this embodiment, a nozzle 103 is formed between the panel lot and 102 made of an insulating material.
A rotor 105 is provided opposite the orifice 104. The rotor 105 is made of stainless steel,
Hydrophilic patterns that are continuous in the axial direction or arranged at regular intervals are provided in the circumferential direction on the outer periphery, and the other regions are formed as hydrophobic surfaces.

Panels 101 and 102 have electrodes 106 and 107, respectively.
．． 108 and 109 are provided, and the electrode i.

6.107 is grounded, and electrodes 108.109 are connected to alternating power supplies 112.113 via switches 110.111. Note that the outputs of the power supplies 112 and 113 have a phase difference of 90°.

The nozzle 103 is equipped with a diaphragm pump 120. The diaphragm pump 120 has electrodes 122 and 123 attached to both sides of a piezo element 121, the electrode 122 in contact with the ink ln is grounded, and the electrode 123 on the opposite side is connected to an alternating power supply 124. Note that the connection surface of the 11 poles 122 with the ink In is covered with an insulating protective film (not shown).

In the printer throat 100 having the above configuration, when an alternating voltage is applied to the electrode 123 from the 'ri source 124, the piezo element 121 vibrates, and the vibration is propagated into the ink In.

Further, the rotor 105 rotates in the direction of the arrow, and as the hydrophilic pattern moves, the ink In is conveyed to the portion facing the orifice 104 in the form of lines or dots.

In this state, the control device switches t based on the image information.
to, i t t is opened and closed and electrode toa, t09
When an alternating voltage is applied to these electrodes 108, 109
A traveling wave electric field curtain traveling toward the orifice 104 is formed between the rotor 1 and the electrodes 106 and 107.
The ink In that is conveyed to the part facing the orifice 104 according to the rotation of the ink droplet 05 is ejected into the air from the orifice 104, and is recorded on a recording medium (not shown). Further, since the ink In is in a state in which vibration is propagated from the diaphragm pump 121 and is easily discharged, an amount of ink In corresponding to the opening/closing time of the switches 110 and 111 is ejected.

G. Seventh embodiment (see FIG. 11) In the printer head 130 of this embodiment, the upper panel 131
An orifice 132 is provided. A pair of piezoelectric elements 13 are provided on the lower panel 133 facing the orifice 132.
5,136 is the provision.

Electrodes 137 are attached to the opposing surfaces of the piezoelectric elements 135 and 136 and to the upper surface of the lower panel 133 located between them, and these electrodes 137 are connected to a DC power source 140. Electrodes 138, 1 are provided on the outer surfaces of the piezoelectric elements 135, 136.
39 are provided, and these electrodes 138, 139 are connected to alternating power supplies 142, 1 through switches 141, 143, respectively.
It is connected to 44. In addition, the alternating box 1i sources 142, 144
have a phase difference of 180°. The piezoelectric elements 135, 136, electrodes 137, 138, and 139 facing the nozzle 134 are covered with an insulating protective film 145, except for the portion of the electrode 137 directly attached to the lower panel 133.

In the printer head 130 having the above configuration, a voltage is applied to the electrode 137 by the DC power supply 140, and the ink is injected.
A charge is injected into the Further, the switches 141143 are simultaneously opened and closed according to image information from the control device, and when the switches 141 and 143 are turned on, alternating voltages are applied from the power supplies 142 and 144 to the electrodes 138 and 139, respectively, and the piezoelectric elements 135 and 136 vibrate. The vibration is propagated into the ink In, and the ink In located at the portion facing the orifice is periodically subjected to force toward the orifice 132 (upward). At the same time, an electric field curtain is formed between and around the electrode 137 and the electrodes 138 and 139, and the ink in the area facing the orifice becomes an ink droplet and is ejected and flies from the orifice 132.

Note that the size of the ink droplets corresponds to the on-time of the switches 141 and 143, and by adjusting the on-time, gradation can be achieved.

H1 printing control circuit (see Figure 12) The circuit configuration of the printing control device will be explained.

host computer, image league, video camera,
Pixel-divided image recording information inputted from a still video camera, etc. is first subjected to arithmetic processing in the nozzle control circuit 200 and output as a digital signal with a gradation for each pixel, and then converted into an analog signal by the D/A converter 201. is converted to This analog signal is the shift clock [SC]
The analog image signals for one life are sequentially transferred to the analog shift register 202 in synchronization with , and the analog image signals for one life are held in the analog shift register 202. analog shift register 2
The analog image signal for one line within 02 is output pixel by pixel and input to the converter 203, where the converter 203 converts it into pulse data corresponding to a voltage value. Then, the nozzle control circuit 200 for each separate AND gate 204
When the line signal [LC] from the line becomes "H" level during recording of one line, each analog switch 205 interposed between the DC power supply 207 and the plurality of individual electrodes B l+ to +Bn The amplifier 206 is the converter 203
DC voltage corresponding to the voltage of each pulse data is applied to the corresponding individual electrodes B l+ to +Bn (see FIG. 13).

J. Manufacture of Panel The manufacture of a panel having a plurality of nozzle slits will be described with reference to FIGS. 14 to 17.

(i) First method (see FIG. 14) a. Chromium film 1 is deposited on the glass plate 150 by sputtering.
51 is screen printed, a photosensitive film (photoresist) 152 is applied thereon, and after drying, a predetermined mask pattern 153 is overlaid and ultraviolet rays 154 are irradiated. As a result, the chromium film 151 and the photoresist 152 in the portions corresponding to the openings of the mask pattern 153 are removed, and the chrome film 151 and the photoresist 152 in the portions corresponding to the shielding portions of the mask pattern 153 are removed.
1a and photoresist 152 remain on the glass plate 150.

b. Next, the photoresist 152 remaining on the chromium film 151a is removed by chemical processing such as etching and washed.

C1 Subsequently, a photoresist 155 is coated on the glass plate 150 to a predetermined layer thickness, and a mask pattern 15 is formed.
3 to expose the chromium film 151a and remove the chromium film 151 from the chromium film 151a.
Form photoresist walls 155a on both sides of a.

d. Finally, the photoresist wall 155a remaining on the glass 150 is thermally cured.

(11) Second method (see FIG. 15) a. Coat a photoresist 161 on a silicon plate 160 and dry it.

51 Next, mask patterns (see FIG. 14(a)) are overlapped and ultraviolet rays are irradiated to form grooves 162 in the photoresist 161 and the silicon plate 160, and the surface layer of the silicon 160 is thermally oxidized by silicon etching. Insulating layer 1
63.

C1 Subsequently, a chromium layer 164 is formed on the groove portion 162 and the surface of the photoresist 161 by sputtering.

d.Finally, the photoresist 161 and the chromium film on its surface are removed using a photoresist stripping solution and a chrome etching solution, followed by cleaning.

(iii) Third method (see FIG. 16) a. A photoresist 171 is applied to the surface of the machinable ceramic plate 170 and dried.

60 Next, a groove 172 is formed using a gussing tool (not shown).

C0 Subsequently, a chromium layer 173 is formed on the groove portion 172 and the surface of the photoresist 171 by sputtering.

d. Finally, the photoresist 171 and the chromium film on its surface are removed using a photoresist stripping solution and a chrome etching solution, and then washed.

(iv) Fourth method (see FIG. 17) a. Grooves 181 are formed on the surface of the machinable ceramic plate 180 using a dicing saw (not shown).

53 Next, using the machinable ceramic plate 180 on which the grooves 181 have been formed as a mold, liquid crystal polymer 182 is applied to the surface on which the grooves 181 have been formed, and is dried and hardened.

C1 Subsequently, the cured liquid crystal polymer plate 182 is removed from the ceramic plate 180, and electrodes 184 are formed in the grooves 183 of the polymer plate 182 by an aluminum ion blating method. Note that at this time, the convex portions of the polymer plate are masked.

(V) Other dimensions of each part of the panel manufactured as described above are, for example, wall pitch: 60 μm, groove width: 30 μm, groove depth: 30 μm, groove length: 5 mm.

Materials used (1) Panels The insulating upper and lower panels that make up each printer head are made of saturated polyester resin, polyamide resin, acrylic resin, ethylene-vinyl acetate copolymer, or ionically crosslinked olefin copolymer. thermoplastic resins such as ionomers), styrene-butadiene block copolymers, polycarbonates, vinyl chloride-vinyl acetate copolymers, cellulose esters, and polyimides; photocurable resins; poly-N-vinylcarbazole, polyvinylpyrene, polyvinylanthracene Resins such as; liquid crystal polymers; mixtures with liquid crystal polymers; or resins formed by appropriately modifying these are used.

Note that the resin has a rating of 1. when measured alone. Ox l
Q l It is desirable to have a volume resistance of 3Ω·cam or more. In addition to the resin, silica-based glasses;
Ceramics such as Mummyable Ceramics.

Ferrite materials etc. can also be used. Furthermore, 10
Glass fiber Tismo (
Potassium titanate, polytetrafluoroethylene) (F
Additives such as resins) may also be added.

Here, adding glass fiber and Tismo improves toughness, dimensional accuracy, and hydrophilicity, and adding polytetrafluoroethylene improves water repellency.

(ii) Insulating film for electrode protection The insulating protective film that protects the electrodes and panels that come into contact with the ink is
Insulating ceramics made of S, O, ALOs, etc.
Insulating materials such as glass, organic materials, enamel, polyimide resin, epoxy resin, acrylic resin, polyethylene resin, polyester resin, etc.
Form into a thin layer by sputtering, coating, dipping, etc.

In Examples 1 and 2, the ink-phobic insulating protective film covering the outside of the panel is mainly made of a material containing a large amount of elements with low surface energy (for example, fluorine). If this ink-phobic insulating protective film is used, the ink that is about to spill from the orifice is repelled and prevented from falling, so that the ink does not fall onto the recording medium and cause noise in the image. In addition, the ejected and flying ink becomes cleaner, and the fine ink droplets that occur between the ejected ink droplets and the ink in the onofis do not scatter onto the recording medium, so there are no small ink droplets on the image. A clear image can be obtained without noise.

By the way, an insulating film to protect the ink contact surface of the electrode is not necessarily necessary (depending on the resistance value of the ink. In other words, when the ink resistance value is ρ<105Ω・cm, an insulating film is provided to protect the individual electrodes from each other. to prevent short circuits.However,
When the resistance value of the ink is ρ>10 sΩ·cm, an insulating film is not necessary.

(iii) Alternating Power Supply for Generating Electric Field Curtain As an alternating power supply for generating electric field curtain, one that outputs, for example, a frequency of 3 KHz and a peak-to-peak voltage (Vp-p) of 200 V is used. Note that the alternating waveform may be a rectangular wave, a triangular wave, or a sawtooth wave. In addition, the alternating current power supply may be a three-phase alternating current, or may be a plurality of single-phase alternating currents with different phases.In short, it is capable of forming an electric field curtain directed from the rear of the nozzle to the orifice. Good to have.

(iv) Heating resistor The heating resistor used in the first and second embodiments includes, for example, a silicon-containing compound such as ZrB, Ta, N, W, N, etc.
i -CrSS no, or P d -A g
The main component is Ru, the Si diffused resistor, the semiconductor PN combination, etc. This heating resistor is provided on the panel by sputtering, vapor deposition, or the like.

(v) Ink As the ink, for example, inks 1 to 5 in the table below are used.

■Ink 1 (Water-soluble ink) ■Ink 2 ■Ink 3 Volume resistivity near, 2 x 10' (Ω・am) Volume resistivity: 1. lX10' (Ω・c-) ■Ink 4 Volume resistance value: 5.3 Instead of black, a heat-generating ink in which the heat-generating resistor powder (0.01 to 0.5 μm) is dispersed may be used.

The general properties of ink used in a recording device will be explained.

Ink agents are divided into two types: pigments (inking pigments, inking materials) dispersed in a liquid that move using this liquid as a carrier, and colorants dispersed in a liquid.
Or it is dissolved but the colorant does not move in the liquid (
, there are two cases in which the entire liquid behaves as an inking material. The former is a two-component system because it uses a carrier liquid for pigment charging and pigment transfer, and the latter is considered a one-component system because it performs inking transfer without using a carrier liquid.

Inks 1 to 5 described above are one-component inks in which a dye is dissolved in an aqueous solvent. Inks 1 to 5 were water-soluble inks having a volume resistivity of 10'8 Ω·CI or less, but organic-component inks having a volume resistivity of 10'8 Ω·cffi or more may be used.

One-component inks have characteristics that two-component inks do not have, such as ease of handling and stability.

In general, pigments do not become water-soluble unless they are surface-treated and have aqueous groups, so they are used as high-resistance inks for actual use.

The charge of the liquid ink agent and pigment in the high-resistance ink will be explained below.

The mechanism of charge generation of pigments dispersed in liquids has many unknown points, just like the triboelectric charging of powder toner for electrophotography.
It is thought that the polarity of pigments is controlled by the following mechanism.

Oil-soluble metal soaps and the like dissociate and adsorb onto pigment particles, giving them a ten-charge charge.

2MX 10 TMX → [TMMXI・+Xe MX Here,
TMX is a pigment particle that has adsorbed undissociated metal soap molecules MX in a liquid, (TMMXI is a pigment particle that has adsorbed a dissociated ion M and has been charged to ■, and Xe MX is a counter ion with a micellar structure. Yes, by adding a resin to a weakly polar pigment such as carbon black, it promotes the dissociation of the metal soap, and the charge is also strongly stabilized.

Hydrogen ions on the surface of the acidic particles are desorbed by the oil-soluble base, and the particles are charged with e-polarity.

T-H + RBgTe +RBH・ Here, T-H is a particle with an acidic group, RB is an oil-soluble base, 1'e is a negatively charged toner particle, and RBH・ is a positively charged counter ion, which is attached to the carbon black surface or adsorbed Acidic groups such as carboxyl groups possessed by the resin become e-charged by oil-soluble bases such as amines. Also, when the metal soap or the like is added, re-adsorption occurs, causing charge reversal. In this way, the pigment surface,
It behaves in various ways depending on the deabsorption of dissociated ions from the substances adsorbed on it.

The properties required of the carrier liquid in the high-resistance ink of the present invention are: (a) It must have an electrical resistance of io''Ω・cm or more to prevent charge leakage; (b) Materials for the ink grooves, orifice members, and electrodes. An isoparaffinic solvent with a boiling point of 120° to 200°C is used because it is chemically inert so that it does not attack the solvent, and (c) it has no toxicity, flammability, or odor.

The developer is made by dispersing pigment particles of approximately 0.2 to 1.0 micrometers (fine particles made by adsorbing resin components that have dispersibility, polarity control, fixing properties, etc. on pigments such as carbon blanks) in a colloidal manner in this carrier liquid. This is what I did.

As the colored body, carbon black or the like is used as a black pigment. There are two types of carbon black, channel black and furnace black, depending on their manufacturing method; the former is suitable for acidic e-pigments, and the latter is neutral or basic and suitable for c-pigments. However, if furnace black is oxidized with something like nitric acid to increase its volatile components and oxygen content, it can be used in pigments as a substitute for channel black.

Colored bodies include: Red: tampstophosphoric acid molybdate lake mixed with indolenine xanthene pigment, mixed lake of cationic azo pigment and bovine santhene pigment Magenta: acidic azo pigment metal salt Orange azo containing niaminotriazoline group Pigment copolymer yellow: Azo dye guanidinium salt, yellow azo pigment Precipitate of xanthine or indolenine dye and molybdotungstophosphoric acid Blue: guanidinium salt, anthracene/phthalocyanine mixture Purple: Metal complex secondary pigment of formazan derivative Since the anchoring group needs to have a certain length in order for the polymer to be strongly adsorbed onto the particles, block or grout copolymers are preferable.

Therefore, polymer chain A is an anchor to the particle surface and is insoluble in the dispersion medium and has a strong affinity for the particle surface, while polymer chain B is a steric repulsion layer that dissolves in the dispersion medium and has almost no affinity for the particle surface. choose. The 1COOH1OH group present in the polymer in a non-aqueous system becomes a potential determining substance for the dispersed particles, giving II@ to the particles.

For polymer chains, methyl methacrylate is used, and for polymer chain B, 10 ammonium salts and sulfonates are used as charged groups such as lauric methacrylate, 2-hexyne methacrylate, and 12-hydroxystearic acid. Polymerize.

The following methods can be considered as methods for controlling pigment chargeability.

■ Adding a soluble metal salt of an organic acid to the carrier liquid using a charge control agent.

For example, metal salts of carboxylic acids such as naphthenic acid, su/leic acid, oleic acid, octylic acid, palmitic acid, stearic acid, metal salts of C11-16 alkyl sulfuric acid, C3-Il+alkyl phosphoric acid, etc. Metals include lead, manganese,
Cobalt, calcium, aluminum, zinc, titanium, etc. are used.

■Add carrier liquids with different dielectric constants.

For example, if a liquid that increases the dielectric constant, such as butanol or isopropanol, is added to the carrier liquid, the developer will
The polarity increases, and when lower aliphatic carbon hydrogen is added, the conductivity decreases and the polarity increases.

■ Utilizes the polar groups of resin that adsorb to pigment particles.

For example, as mentioned above, the polar groups of the polymer adsorbing or grouting pigments include -NH,, -CONH,, -CN, -OH, -N(cH
3) t, -COOH, -CH-CH,, -CC.

＼　1 No, etc. are used.

■ Adding highly charged pigments.

For example, metal-free phthalocyanine is added.

■Add other surfactants.

For example, polyethylene glycol having quaternary ammonium or NH groups is added.

■Charging due to carrier liquid.

As a dispersion medium for pigment particles, isoparaffin petroleum agents, glycerin, titanium, dioxane, ethylene glycol, and silicone oil are usually used.

〔Effect of the invention〕

As is clear from the above description, the recording device according to the present invention includes a nozzle made of an insulating material, a printing material supplied into the nozzle, and a printing material that is sandwiched between the printing material near the opening of the nozzle on both sides. or at least two individual electrodes arranged on one side, and an electric field forming means for applying a voltage to the individual electrodes according to image information to apply a voltage curtain force to the printing material near the nozzle opening toward the opening; Means is provided for applying a force to force the printing material near the nozzle opening toward the opening by changing the volume of the printing material within the nozzle.

Therefore, in this recording apparatus, the printing material near the nozzle opening is urged toward the opening.

That is, it is maintained in a state where it can be easily discharged from the nozzle. Therefore, when a signal corresponding to image information is applied to the individual electrodes by the electric field forming means, the printing material near the opening is ejected and flies into the air even by a slight electric field curtain force formed between the individual electrodes.

Therefore, responsiveness to image signals is improved, and dot density gradation and image resolution are improved.

Further, since the trail of the ejected printing material is immediately replenished with the printing material from behind, the switching response frequency of the individual electrodes is increased and high-speed printing becomes possible.

[Brief explanation of drawings]

1st. 2. 3 shows the printer head of the first embodiment, FIGS. 1 and 2 are partial cross-sectional views, FIG. 3 is a partial perspective view, and FIGS. 4 and 5 are partial cross-sectional views of the printer head of the second example.
6 is a partial sectional view of the printer head of the third embodiment, FIG. 7 is a partial sectional view of the printer head of the fourth embodiment, and FIG. 8 is a partial sectional view of the printer head of the fourth embodiment.
, 9 is a partial sectional view of the printer head of the fifth embodiment, FIG. 10 is a sectional view of the printer head of the sixth embodiment, and FIG. 11 is a sectional view of the printer head of the sixth embodiment.
The figure is a sectional view of the printer head of the seventh embodiment, FIG. 12 is a control circuit diagram, FIG. 13 is a timing chart showing the output state of signals in the print control circuit, and FIGS.
17(d) to 17(a) to (C) are process diagrams showing the manufacturing process of the panel. 1... Printer head, 2... Upper panel, 3...
Lower panel, 5... Nozzle, 6... Orifice, 7° 8... Individual electrode, 9. to...heating resistor, In...
...Ink, In' ...Ink drop. Patent Applicant Minolta Camera Co., Ltd. Agent Patent Attorney 1 J6 Figure 3 Figure 1 J6 Figure 7 rS14 Figure 15 It) +6 Figure 17 (at)

Claims (1)

[Claims] (1) A recording device that supplies printing material to a recording medium and records the information, comprising a nozzle made of an insulating material, a printing material fed into the nozzle, and a printing material sandwiched near an opening of the nozzle. at least two individual electrodes arranged on both sides or on one side, and applying a voltage to the individual electrodes according to image information;
an electric field forming means that applies an electric field curtain force to the printing material near the nozzle opening that advances toward the opening; and a force that pushes the printing material near the nozzle opening toward the opening by changing the volume of the printing material within the nozzle. A recording device characterized by comprising: means for imparting.