JP2000079702A - Method and device for ink jet recording - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device for ink jet recording wherein ink is ejected only from portions corresponding to an image pattern by ejecting the ink from nozzles in a head. SOLUTION: A plurality of ejection elements of a head 2 are positioned in a roll. Ink is supplied to the ejection elements by contacting a supplying roll 4 thereto. By using an optical shutter array 21, an ultraviolet ray is emitted to a portion on the head 2. The ink 3 is transferred to only the emitted portion on the head 2 from the supplying roll 4, then the ink 3 enters the inner section of an ejection nozzle to be held therein. The ink 3 entering the inner section of the ejection nozzle is ejected by virtue of heat of a heating element, then the ink is adhered to a surface of a paper 30.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording method for ejecting a liquid ink used in a copying machine, a printer, a facsimile, and other printing machines and image forming apparatuses onto a recording medium such as paper for recording. .

In particular, ink is supplied from an ink discharge port and ink is supplied only to the ink discharge port of a target image pattern portion, or ink is discharged after the ink is left. In particular, the present invention relates to a full multi-type ink jet recording method and a recording apparatus capable of high-speed recording.

[0003]

2. Description of the Related Art One of the most excellent advantages of the ink jet recording method is that the ink jet head can hardly be worn out or damaged because it can record on a recording medium such as paper in a non-contact manner. is there. In addition, in order to supply liquid such as ink from the storage tank for use,
The handling method is very simple.

However, as disclosed in JP-A-6-55732, the ink jet recording method supplies ink from an ink supply port and discharges ink from the ink discharge port. For this reason, a complicated ink supply path, a common liquid chamber, and the like are arranged inside the ink jet head, and a design has been made so that air bubbles and foreign matters do not remain inside.

[0005] However, even if such various means are used, much time is required for suction recovery. Furthermore, in a full multi-type ink jet system capable of printing on a recording paper width, if air bubbles are generated inside the ink jet head, more suction recovery time and ink for suction recovery are required to remove the air bubbles. Was.

In order to solve these problems, it has been found that such problems can be solved by supplying ink from the ink ejection port side.

However, it is easy to supply ink to the entire surface of the ink jet head, but it is difficult to supply ink only to an arbitrary image pattern.

Here, the configuration of a conventional ink jet head will be described with reference to FIG.

In FIG. 8, reference numeral 3 denotes ink, 10 denotes an ink supply port, 15 'denotes a discharge control unit, 110 denotes an ink discharge drive unit, 111 denotes an ink supply path, 112 denotes a holding substrate, 113
Individual electrodes 114 are individual signal lines.

In the head having the structure shown in FIG. 8, the ink 3 is supplied to the ink supply path 111,
When the ejection is performed from the beginning, the ink ejection drive unit 110 generates heat based on the individual signal. With such a structure, it is difficult to supply ink only to an arbitrary image pattern portion.

[0011] Then, when the prior art was investigated, no such technology was disclosed in the past.

[0012]

Therefore, according to the present invention, ink is supplied to an ink jet head from its ink discharge port, and the ink is discharged only from the ink discharge port corresponding to a required arbitrary image pattern. It is an object to provide an inkjet recording method and apparatus for forming an image.

[0013]

In order to solve the above problems, according to the present invention, a flat or curved ink jet head is formed by using an arbitrary portion of a plurality of ink ejection ports of an ink jet head as ink supply means. The ink is supplied to this portion by a transfer method, a coating method, or a spraying method.

The following two methods were examined as a method of transferring.

One method is to directly supply ink to an arbitrary portion of the planar ink jet head.

The other is a method in which ink is supplied to the entire surface of the planar ink jet head, and ink is removed from other portions so that ink remains only in necessary portions.

The means of the former method will be described. The ink ejection port serving as an ink storage unit of the planar ink jet is formed of, for example, silicon rubber containing a titanium oxide which causes a photocatalytic reaction. Since silicone rubber is hydrophobic and the ink used in the inkjet method is generally an aqueous ink, the aqueous ink does not adhere to the ink ejection surface of the inkjet head.

However, by irradiating only necessary portions with light, it is possible to change from hydrophobic to hydrophilic.

Further, since the ink ejection port has a concave shape inside, the ink is adsorbed inside the ink ejection port by a capillary phenomenon. By controlling the portion to be irradiated with light as described above, it becomes possible to supply ink to the ink ejection openings of any portion. After that, if the ink is ejected, an image is formed on the recording medium according to the image pattern using the ink.

Furthermore, if the size of the ink discharge port is set to a capacity capable of storing several types of ink, it is possible to form an image having a plurality of colors with one ink jet head. That is, a color image can be formed.

Next, the second method will be described.

First, an ink jet head is manufactured as a hydrophilic structure. After the ink is deposited on the entire surface of the ink jet head, the ink is removed by bringing the ink removing member into contact. By forming the removing member as a member having a property in which an arbitrary portion irradiated with light is converted to hydrophilic by a photocatalytic reaction, the ink is transferred to the ink removing member and removed. In this way, it is possible to form an image on a recording medium by ejecting the ink after the ink is left only in a necessary image pattern portion.
The inkjet head is also made of a material that causes a slight photocatalytic reaction, and then assists in adsorption and removal,
Adhesion and removal of ink becomes easy.

In this case, however, the ink attraction force of the ink jet head is KI, the attraction force of the ink removing member when light is irradiated is KJ, and the attraction force of the ink removing member when light is not irradiated is KJ. If KN, the following relationship must be established.

KN << KI <KJ or KN << K
I << KJ, preferably, KN << KI << KJ
It is.

In order for the ink jet head to satisfactorily discharge the ink or to remove the ink from the ink jet head satisfactorily, the shape of the ink discharge port is defined as follows: In consideration of the tendency of the ink to become spherical due to surface tension, it is desirable that the ink has a shape satisfying the following expression.

H <R / 2 Preferably, H <R / 3.

Alternatively, if the sectional shape of the ink discharge port is not circular but polygonal such as triangular or square,
The radius of curvature of the ink droplet generated there is described as CR as follows.

H <CR Desirably, H <2CR / 3.

By using the above-described method, it is possible to arrange the ink at the ink ejection port corresponding to the position of an arbitrary pattern corresponding to the image.

Further, as a material that causes a photocatalytic reaction to convert from hydrophobic to hydrophilic, titanium oxide, zinc oxide, tungsten oxide, tin oxide, iron oxide, silicon oxide, bismuth oxide, and strontium titanate are known. Has been
Materials combining these also exhibit similar properties. Also,
As a matter of course, the carrier material supporting the material needs to be a material that transmits light, and examples thereof include transparent glass and plastic.

Among them, titanium oxide is particularly remarkable in this phenomenon, and there are rutile type and anatase type, both of which can be used, and transparent type polyester, polycarbonate, polypropylene, polyethylene, polystyrene. , Polysulfone and the like.

Further, the type of light that causes a photocatalytic reaction may be any light having a wavelength of about 550 nm or less, such as visible light, ultraviolet light, X-ray, excimer laser, carbon dioxide laser, and blue semiconductor laser. Alternatively, a material which changes into hydrophilic and hydrophobic by a photochromism phenomenon may be used. For example, epoxy indanone, spirobenzopyran, or a derivative thereof may be used.

However, any light having a wavelength longer than this can be used as long as it can induce a photocatalytic reaction or a photochromic reaction.

[0034]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the ink jet recording method of the present invention will be described in detail with reference to the drawings.

(Embodiment 1) First, an embodiment of the ink jet recording method of the present invention will be described with reference to FIGS.

FIG. 1 is a schematic side view showing an example of an ink jet recording apparatus suitable for carrying out one embodiment of the ink jet recording method of the present invention. In FIG. 1, reference numeral 1 denotes an ink-jet discharge element, which is schematically constituted by an ink discharge port 10 and a heating element 11 which communicates with the ink discharge port and generates heat energy sufficient to discharge ink.

The ink-jet head 2 is configured by arranging the plurality of ink-jet ejection elements 1 in a roll shape. The ink jet head 2 is in contact with a supply roll 4 for supplying the ink 3 to the plurality of ink jet ejection elements 1. The supply roll 4 has an ink tank 5 for storing the ink adhered and supplied to the surface thereof. Also, a doctor blade 6 for defining the amount of application on the surface of the supply roll 4 is disposed in close proximity.

FIG. 2 is a schematic perspective view showing the internal structure of the ink jet ejection element shown in FIG.
In FIG. 2, the ejection port 10 of the inkjet ejection element 1 is
Is formed of a mixed film of silicon resin and titanium oxide having a depth of 7 μm, and a heating element 11 for discharging ink is formed on the bottom surface of the discharge port 10. Its size is almost the same as the diameter of the discharge port 10 of 16 μm.

As shown in FIG. 1, even when the supply roll 4 is brought close to the roll-shaped ink jet head 2 in a dark room without light, no ink adheres. When the ultraviolet light from the inkjet head 2 is partially irradiated using the optical shutter array 21, only the portion is irradiated from the supply roll 4 to the inkjet head 2.
The ink 3 enters the inside of the ink discharge port 10 by being transferred to the side, and is held therein. This discharge port 10
By discharging the ink 3 that has entered the inside by the heat generated by the heating element 11, the ink 3 can be attached to the surface of the paper 30 as a recording medium.

After that, the ink remaining on the discharge port surface of the ink jet head 2 and its periphery is removed by the cleaning roller 5.
Clean with 0. In the inkjet head 2,
Wirings 12 for controlling a plurality of heating elements 11 are arranged, and basically, one horizontal row generates heat at the same time. By doing so, the complexity of the wiring can be avoided. The ink-jet ejection element 1 in the ink ejection port 10 into which the ink has not entered does not eject ink even if it generates heat, so that printing does not occur. This is the basic configuration of an ink jet recording method for forming an image by partially supplying ink to an ink jet element that ejects ink.

(Embodiment 2) Next, another embodiment of the ink jet recording method of the present invention will be described with reference to FIG.

The feature of this embodiment resides in a structure in which ink is ejected by partially removing ink.

FIG. 3 is a schematic perspective view showing an example of an ink jet recording apparatus suitable for carrying out another embodiment of the ink jet recording method of the present invention.

In FIG. 3, an ink supply roll 4 supplies ink 3 to an inkjet discharge element 1 on the entire surface of a hydrophilic roll-shaped inkjet head 2. Next, ultraviolet rays 20 were partially applied to the ink removal roll 42 on which the member 41 for generating a photocatalytic reaction was formed.
Irradiation is used to convert from ink-phobic to high hydrophilicity. When the ink removing roll 42 in this state is brought into contact with the inkjet head 2, the inkjet head 2
The ink 3 in the ink discharge port 10 is the ink removing roll 4
2 is removed from the ink jet head 2 in accordance with the image pattern, losing the suction force due to the high ink affinity. In this state, the ink-jet head 2 is foamed by the heat generated by the heating element 11 to perform ink discharge by an ink-jet method. By doing so, ink jet recording according to the image pattern becomes possible. Naturally, even if all the elements generate heat, heat generation and bubbling of the ink jet discharge element 1 cannot occur in the ink discharge port 10 where there is no ink, so that ink discharge, flying, adhesion and recording do not occur.

Although it is possible to drive an ejection element that does not selectively generate heat from the heating element 11 in the ink-free ink ejection port 10, it is impossible to complicate the configuration due to complicated wiring and complicated control. Not, but difficult.

Thereafter, the ink jet head 2 is cleaned by the cleaning roller 50, and then proceeds to the next step of adhering ink, which is continuously repeated.

If the quality of the image quality does not matter, the cleaning roller 50 may be removed. Further, in the case of a plurality of color tones, for example, in the case of color or light and shade, it is possible to replace the ink to be supplied and adhered with a different color or density, but if such a configuration is used in a plurality of colors, ,
It can also be formed by arranging four colors of yellow, magenta, cyan, and black. Rather, the advantage of high-speed printing is greater.

The relationship between the diameter R and the depth H of the discharge port 10 is as follows:
Basically, the depth H is １ ／ or less of the diameter R, although it depends on the surface tension and wettability of the ink in order to supply and remove the ink satisfactorily. There is a need. This is because, when the depth of the ink ejection port 10 is larger than the radius R / 2 of the outlet of the ejection port, bubbles 60 are generated between the heating element 11 of the inkjet ejection element 1 and the ink 3, and the inkjet ejection is performed. Is not generated. Further, even in the case of ink removal, the ink adhering to the heating element 11 may be cut off in the middle when adhering to the ink removing roll 42 and may remain. In fact, supply and removal occur in a very short time, so considering the speed of ink capillary movement,
The relationship between the diameter R and the depth H of the discharge port 10 is H <R / 3
Is desirable.

When the shape of the ink ejection port is not circular,
It is desirable that H <CR / 3 in relation to the radius of curvature CR of the ink droplet generated according to the shape.

In the configuration of the present embodiment, the light is controlled by the optical shutter array 21. However, in the embodiment, as described later, the scanning of the excimer laser beam 22 and the semiconductor blue laser 23 can be controlled. Irradiation O
Any light can be used as long as it can excite the photocatalytic reaction that can be turned off in N and OFF, and any light can be used as long as the system can control the light. Although it is relatively dangerous, X-ray or carbon dioxide laser may be used if care is taken in handling.

[Embodiment 1] An embodiment of the ink jet recording method of the present invention will be described.

1 and 2, the discharge port 10 of the ink jet 1 is made of a mixed film of silicon resin and titanium oxide having a depth of 7 μm, and a heating element 11 for discharging ink is provided on the bottom surface of the discharge port 10. The size of the outlet is almost 1
0 is 16 μm in diameter.

Here, a method for manufacturing the above-described ink jet ejection element will be described with reference to FIG.

First, a roll coat layer of an epoxy resin was formed on a roll-type metal roll, and a heating electrode array sheet 25 having a two-layer structure of polyimide was bonded and fixed thereon. The sheet 25 has a heating element 11 in which a platinum heating resistor 26 and a protective layer 28 such as a SiN heat storage layer 27 or Ta ₂ O ₅ formed thereon are formed in advance.

Next, a solution of titanium oxide (anatase type) having a particle size of 0.01 μm mixed with an uncured silicon resin or a precursor thereof was applied thereon by a dipping method. Thereafter, the mixture was kept at a temperature of 180 ° C. for 1 hour, and was hardened by condensation polymerization.

Next, a diameter of 16 μm was
m discharge ports 10 were formed on the heating elements 11 while detecting the position of the array sheet 25. At this time, the protective layer 28 was slightly scraped off by the carbon dioxide gas laser to form the almost completely circular ink ejection port 10.

The roll-shaped inkjet head 2 manufactured as described above is arranged as shown in FIG.
By supplying an ink having a composition of 3%, IPA (isopropyl alcohol) 10%, black dye 5%, and diethylene glycol 3%, the following inkjet-type ejection test was performed.

Even if the ink supply roll 4 is brought close to the roll-shaped inkjet head 2 in a dark room without light,
No ink adhered, but when the ultraviolet rays 20 were applied to the entire surface of the roll of the inkjet head 2, the ink 3 adhered to almost the entire surface. Here, a current was applied only to the portion of the row where the ink jet head 2 came closest to the paper 30 to generate heat, thereby causing the ink 3 to adhere to the paper 30. Paper 30
The distance between the ink jet head 2 and the ink jet head 2 (inter-paper distance) is 0.1.
By setting it to 3 mm, the ink jet head 2 was prevented from rubbing on the paper.

Although no particular problem occurred when the inter-paper distance was set to 1 mm, when the inter-paper distance was set to 2 mm, the position where the fine ink adhered was partially shifted.

Next, when light having a wavelength of 550 nm or less is partially irradiated using the optical shutter array 21, the ink 3 is transferred from the ink supply roll 4 to the ink jet head side 2 only on the irradiated portion, and Since the ink 3 enters and is held in the ink ejection port 10, it is possible to partially supply the ink.

Therefore, only the discharge ports in the row portion closest to the paper are sequentially supplied with current to generate heat, and the ink 3 in the discharge ports 10 is heated by the heat generating element 11 to generate heat.
The recording medium was adhered to paper 30 as a recording medium. As a result, it is preferable that the feed speed of the inkjet head 2 and the paper 30 on which the predetermined image pattern is formed on the paper 30 be equal, but it is preferable to form the ink ejection ports 10 continuously.
If this is not possible due to the wiring, the feed speed of the inkjet head 2 may be higher than the feed speed of the paper. Because the non-contact, the inkjet head 2
This is because the rotation speed of the paper and the moving speed of the paper do not need to match.

Thereafter, the ink remaining around the discharge port of the ink jet head 2 was cleaned and cleaned by the cleaning roller 50. In particular, when the quality of the image does not matter, there is no need to clean the image. The reason is that even if the ink adheres around the ejection port 10 of the inkjet head 2, the ink ejection port 10
This is because the ink is not ejected unless it enters the inside. However, when the number of times increases, the residual ink is accumulated and intrudes into the ink ejection port 10 and may cause noise. Therefore, it is not necessary to continuously clean the ink. We decided to clean it periodically.

[Embodiment 2] Next, an embodiment in which ink is partially removed to discharge ink will be described with reference to FIG.

First, the ink 3 was supplied from the ink supply roll 4 to the polysulfone hydrophilic roll-shaped inkjet head 2 to the inkjet discharge elements 1 on the entire surface.

Next, the ink removing roll 42 on which the member 41 for generating the photocatalytic reaction was formed was partially irradiated with ultraviolet rays 20 using the optical shutter array 21 to convert the ink-phobic property to a high hydrophilic property. The ink removing roll 42 is manufactured by the method described in the first embodiment. However, no electrode array sheet is disposed on the ink removing roll 42.

On the other hand, the ink jet head 2 has a structure in which a polysulfone layer is formed on the electrode array sheet described in the first embodiment by an electrodeposition coating method, and an ink discharge port 10 is formed thereon by an excimer laser. It is.
The diameter of this discharge port was 16 μm and the depth was 7 μm.

When the ink removing roll 42 in this state is brought into contact with the ink jet head 2, the ink 3 in the discharge port 10 of the ink jet head 2 loses the suction force due to the high ink affinity of the ink removing roll 42, and the ink It was removed from the head 2 according to the image pattern. In this state, the inkjet head 2 is connected to the heating element 1.
The ink was ejected by foaming by the heat generation of No. 1. By doing so, ink jet recording according to the image pattern became possible. Naturally, even if all the elements generate heat, heat generation and bubbling of the ink jet discharge element 1 cannot occur in the ink discharge port 10 where there is no ink, so that ink discharge, flying, adhesion and recording do not occur.

Although it is possible to drive an ejection element that does not selectively generate heat from the heating element 11 in the ink-free ink ejection port 10, the structure cannot be complicated due to complicated wiring and complicated control. Not, but it was difficult.

Thereafter, the ink jet head 2 was cleaned by the cleaning roller 50, and then moved to the next step of adhering ink, and this was continuously repeated, whereby an image could be formed.

If the quality of the image quality does not matter, the cleaning roller 50 may be removed.

[Embodiment 3] An embodiment suitable for forming images of a plurality of colors in the ink jet recording method of the present invention will be described with reference to the drawings.

FIG. 4 is a schematic sectional view showing another example of an ink jet recording apparatus suitable for carrying out the ink jet recording method of the present invention.

The ink jet recording apparatus shown in FIG. 4 has an ink jet head 2 in which a plurality of ink jet ejection elements 1 are arranged in a roll shape, and
A supply roll 4 for supplying Y, 3M, 3C, 3B, ink tanks 5Y, 5M, 5C, 5B for attaching ink to the ink supply roll 4, and a doctor blade 6 for defining the application amount of each ink. It is configured.

Further, the cleaning washer portion for cleaning is one set. According to this method, in order to form one image, the paper 30 must be fixed to the rotating drum the number of times corresponding to the required color and rotated to deposit ink.

FIG. 5 is basically common to the ink jet recording apparatus shown in FIG. 4, but is characterized in that images of a plurality of colors can be formed in one paper pass.

That is, the dedicated ink-jet heads 2 for each color are arranged on the paper transport path.
, And a plurality of cleaning devices are arranged.

Naturally, even when the step of partially attaching ink in the present embodiment is changed to the step of partially removing ink as shown in the second embodiment, a plurality of color images Can be formed.

[Embodiment 4] In this embodiment, the first embodiment will be described.
The optical shutter array 21 was changed to an excimer laser scanning unit 22. The excimer laser was irradiated using a scanning unit 22 while rotating the inkjet head 2 using an NL1000 type manufactured by Lambda Corporation. The irradiation time is 2 microseconds per spot, the output power is 1 mW, and the deflected PLZT shutter 2
4 was performed.

The size of one spot is an elliptical spot having a major axis of 35 μm and a minor axis of 25 μm. The rotation of the roll of the inkjet head 2 and the scanning of the laser unit 22 were servo-synchronized with each other so that this spot would pass over the nozzle row in which the ink discharge ports 10 were formed.

As a result, ultraviolet rays are emitted from the light shutter array 21.
A better image was obtained than in the case where the control was performed according to. This is considered to be because the output of one spot is stable, and the uniformity is higher in the one-beam system which does not pick up the fluctuation variation of a plurality of shutter arrays.

Next, the excimer laser unit 22 was replaced with a semiconductor blue laser unit 23. The semiconductor blue laser unit 23 is a recently developed laser having a short wavelength, and a laser unit manufactured by Matsushita Electric is used. Since the semiconductor laser is a semiconductor laser, the oscillation itself can be controlled by an electric signal. Therefore, it is not necessary to use the deflection shut-off shutter 24 of the PLZT as described above. The control level can be up to about 1 GHz, and one clock and 2 microseconds used here can be easily achieved. The output was also 1 mW, and the size of the laser spot was a spot having a major axis of 35 μm and a minor axis of 25 μm. As a result, a good image can be formed.

[Embodiment 5] In this embodiment, as shown in FIG. 7, the structure of the ink-jet head 2 is formed by ejecting ink with an ink-repellent ejection port structure 70 at the center of an ink-repellent structure 71. Outlet 10 was configured. The manufacturing method is electrode sheet 2.
5, a polysulfone layer 72 is formed to a thickness of 3 μm, a 0.1 μm Ni layer is formed thereon by ion plating, and only the nozzle and its peripheral portion are partially removed by an excimer laser. The eutectoid plating layer of carbon fluoride and nickel was formed, and the photocatalyst layer 40 was dipped again. Thereafter, curing was stabilized by heat treatment.

Thereafter, an ink ejection port 10 having a diameter of 16 μm was formed on the heating element 11 by surface polishing cutting and carbon dioxide laser irradiation.

In this way, it is possible to wrap each ink ejection port 10 in an ink-repellent area. With this method, even if the ink is supplied slightly in excess, the ink does not move in the horizontal direction even when the ink becomes droplets.

Thus, as shown in FIG. 6, two kinds of inks were supplied to the ink jet head 2, but the bleeding movement in the horizontal direction could be prevented. Next, image recording was performed by ejecting ink at a position where the inkjet head 2 was closest to the paper 30, and a good color image could be formed.

However, since there was a portion where slight lateral bleeding was observed, the diameter of the ink ejection port was reduced to 19 μm.
m. As a result, it was possible to reliably prevent the displacement of the position of the printed image due to bleeding.

According to this method, it is possible to reduce the number of places where four ink jet heads 2 are required to two. It is conceivable that simultaneous selection of three colors or four colors and ink ejection will be possible if a better shape and material are selected. It is determined that the number of inkjet heads 2 can be reduced by that much.

(Others) It should be noted that the present invention includes a means (for example, an electrothermal converter or a laser beam) for generating thermal energy as energy used for discharging ink, particularly in an ink jet recording system. An excellent effect is obtained in a recording head and a recording apparatus of a type in which the state of ink is changed by the thermal energy. This is because according to such a method, it is possible to achieve higher density and higher definition of recording.

The typical configuration and principle are described in, for example, US Pat. Nos. 4,723,129 and 4,740.
It is preferable to use the basic principle disclosed in the specification of Japanese Patent No. 796. This method is a so-called on-demand type,
Although it can be applied to any type of continuous type, in particular, in the case of the on-demand type, it can be applied to a sheet holding liquid (ink) or an electrothermal converter arranged corresponding to the liquid path. By applying at least one drive signal corresponding to the recorded information and giving a rapid temperature rise exceeding the nucleate boiling, heat energy is generated in the electrothermal transducer, and film boiling occurs on the heat acting surface of the recording head. Liquid (ink) corresponding to this drive signal on a one-to-one basis.
This is effective because air bubbles inside can be formed. The liquid (ink) is ejected through the ejection opening by the growth and contraction of the bubble to form at least one droplet. When the drive signal is formed into a pulse shape, the growth and shrinkage of the bubble are performed immediately and appropriately, so that the ejection of a liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable. As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. Further, if the conditions described in US Pat. No. 4,313,124 relating to the temperature rise rate of the heat acting surface are adopted, more excellent recording can be performed.

The configuration of the recording head is not limited to the combination of a discharge port, a liquid path, and an electrothermal converter (a linear liquid flow path or a right-angled liquid flow path) as disclosed in the above-mentioned specifications. U.S. Pat. No. 4,558,333 and U.S. Pat.
A configuration using the specification of Japanese Patent No. 59600 is also included in the present invention. In addition, Japanese Unexamined Patent Application Publication No. 59-123670 discloses a configuration in which a common slit is used as a discharge portion of an electrothermal converter for a plurality of electrothermal converters, and an aperture for absorbing a pressure wave of thermal energy is provided. The effect of the present invention is effective even if the configuration is based on JP-A-59-138461, which discloses a configuration corresponding to a discharge unit. That is, according to the present invention, recording can be reliably and efficiently performed regardless of the form of the recording head.

Further, the present invention can be effectively applied to a full-line type recording head having a length corresponding to the maximum width of a recording medium on which a recording apparatus can record. Such a recording head may have a configuration that satisfies the length by a combination of a plurality of recording heads, or a configuration as one integrally formed recording head.

In addition, even in the case of the serial type as described above, a recording head fixed to the apparatus main body, or an electric connection with the apparatus main body or ink from the apparatus main body by being mounted on the apparatus main body. The present invention is also effective when a replaceable chip-type recording head that can be supplied or a cartridge-type recording head in which an ink tank is provided integrally with the recording head itself is used.

It is preferable to add a recording head ejection recovery unit, a preliminary auxiliary unit, and the like as the configuration of the recording apparatus of the present invention since the effects of the present invention can be further stabilized. If these are specifically mentioned, the recording head is heated using capping means, cleaning means, pressurizing or suction means, an electrothermal transducer, another heating element or a combination thereof. Pre-heating means for performing the pre-heating and pre-discharging means for performing the discharging other than the recording can be used.

Further, the types and the number of the recording heads to be mounted are, for example, not only those provided for one color ink but also plural inks having different recording colors and densities. A plurality may be provided. That is, for example, the printing mode of the printing apparatus is not limited to a printing mode of only a mainstream color such as black, but may be any of integrally forming a printing head or a combination of a plurality of printing heads. The present invention is also very effective for an apparatus provided with at least one of the recording modes of full color by color mixture.

In addition, in the embodiments of the present invention described above, the ink is described as a liquid. However, an ink which solidifies at room temperature or lower and which softens or liquefies at room temperature may be used. In general, the ink jet method generally controls the temperature of the ink itself within a range of 30 ° C. or more and 70 ° C. or less to control the temperature so that the viscosity of the ink is in a stable ejection range. Sometimes, the ink may be in a liquid state. In addition, in order to positively prevent temperature rise due to thermal energy by using it as energy for changing the state of the ink from a solid state to a liquid state, or to prevent evaporation of the ink, the ink is solidified in a standing state and heated. May be used. In any case, the application of heat energy causes the ink to be liquefied by the application of the heat energy according to the recording signal and the liquid ink to be ejected, or to start solidifying when it reaches the recording medium. The present invention is also applicable to a case where an ink having a property of liquefying for the first time is used. In such a case, the ink
JP-A-54-56847 or JP-A-60-7
As described in Japanese Patent Publication No. 1260, it is also possible to adopt a form in which the sheet is opposed to the electrothermal converter in a state where it is held as a liquid or solid substance in the concave portion or through hole of the porous sheet. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

In addition, the form of the ink jet recording apparatus of the present invention is not only used as an image output terminal of an information processing apparatus such as a computer, but also for a copying apparatus combined with a reader or the like, and a facsimile apparatus having a transmission / reception function. It may take a form.

[0097]

As described above, the present invention has the following effects.

According to the present invention, since the ink is supplied from the discharge port of the ink jet head, the structure of the ink jet head can be simplified, and a wide flat or roll-shaped ink jet discharge head can be easily formed. It also simplifies the ink supply system,
Elimination of residual air bubbles and the like in the ink flow path is eliminated, and there is no longer a long start-up time such as suction recovery. Then, the printing operation can be started relatively directly. Also,
Since it is an ink jet recording method, not only does the ink jet head not come into contact with a medium such as paper, there is no wear of the ink jet head, but also the feed speed of paper and the movement and feed speed of the ink jet head can be arbitrarily changed. This makes it possible to form an excellent high-quality image. In addition, since ink is supplied directly from the ink discharge port to the ink-jet discharge element, not only ink having relatively high fluidity as in the related art but also viscous ink can be easily supplied, and ink-jet discharge becomes possible. .

According to the present invention, at the stage of arranging the driving of the planar or roll-shaped inkjet head, all the inkjet ejecting elements are simultaneously ejected, or only one row of the closest position to paper or the like is ejected and driven simultaneously. In addition, an image can be formed by performing ink-jet ejection only on a certain portion of the ink. Therefore, unlike the conventional ink jet head, it is not necessary to be able to drive and control all the elements one by one, and it becomes easy to drive a large number of ink jet ejection elements.

According to the present invention, the ink can be partially arranged at an arbitrary position by the photocatalytic reaction. Therefore, by performing the ink jet discharge, the image can be formed well, and at the same time, the ink can be continuously formed. Supply and removal become possible, and continuous and high-speed image formation becomes possible.

According to the present invention, the inkjet heads can be arranged on a wide plane from a linear inkjet arrangement in one row.

According to the present invention, by using such a material, a favorable photocatalytic reaction can be maintained, and the ink can be partially and continuously arranged.

According to the present invention, a plurality of color tones and types of ink can be used, so that a plurality of color tones and color images can be formed. Further, by changing the ink supply unit, any kind of ink can be easily used, and a high-quality image can be obtained.

According to the present invention, it is possible to use light sources of various colors, and the scope of the design and method of the apparatus according to the situation is widened.

According to the present invention, a good image forming apparatus can be manufactured. As a result, not only the time required for suction recovery until startup, which required the longest time in the inkjet recording apparatus, can be reduced, but also the consumption of ink required for suction recovery can be reduced, which is economically advantageous. is there. Furthermore, since an ink jet head corresponding to the width of the recording paper is easily formed, a full-line printer can be easily manufactured, and high-speed printing can be performed.

According to the present invention, the supply and removal of the ink and the ink jetting can be performed satisfactorily by taking into account the aggregation due to the surface tension of the ink.

According to the present invention, since the cleaning and cleaning device is provided, good image formation can be continuously performed even if image formation is repeatedly performed.

As described above, according to the present invention, not only an excellent ink jet recording method can be provided, but also a high-speed full-line printer or printing machine with excellent print quality can be manufactured.

[Brief description of the drawings]

FIG. 1 is a schematic side view showing an example of an inkjet recording apparatus suitable for carrying out an embodiment of an inkjet recording method of the present invention.

FIG. 2 is a schematic perspective view showing the internal structure of the inkjet discharge element shown in FIG.

FIG. 3 is a schematic perspective view showing an example of an ink jet recording apparatus suitable for carrying out another embodiment of the ink jet recording method of the present invention.

FIG. 4 is a schematic sectional view showing another example of a color image recording apparatus suitable for carrying out the ink jet recording method of the present invention.

FIG. 5 is a schematic sectional view showing another example of the color image recording apparatus shown in FIG.

FIG. 6 is a schematic cross-sectional view of a color image recording apparatus that utilizes a method in which two-color inks are superimposed and held on one inkjet head and ink is simultaneously ejected.

FIG. 7 is a schematic explanatory view of the surface of an ink jet head used in the color image recording apparatus shown in FIG.

FIG. 8 is a schematic sectional view showing a configuration of a conventional ink jet head.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink-jet discharge element 2 Ink-jet head 3 Ink 3Y Yellow ink 3M Magenta ink 3C Cyan ink 3B Black ink 4 Ink supply roll 5 Ink tank 6 Doctor blade 10 Ink discharge port 11 Heating element 12 Wiring 14 Shutter array control signal line 15 Shutter control section Reference Signs List 20 light, ultraviolet light 21 optical shutter array 22 excimer laser and its unit 23 semiconductor blue laser unit 24 PLZT deflection shutter 25 electrode sheet 26 platinum heating resistor 30 paper 40 photocatalytic reaction layer 41 photocatalytic reaction member 42 ink removing roll 43 suction pipe 44 cleaning liquid 48 suction ink recovery roller 50 cleaning roll 60 air bubble 70 discharge port structure 71 ink repellent structure 72 polysulfone layer 83 paper feed roller 100 paper feed roller DOO 110 ink discharge drive unit 111 the ink supply path 112 holding substrate 113 individual electrodes 114 individual signal lines

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 2C056 EC08 EC28 EC71 FA03 JB03 JB15 2C057 AF99 AG46 BA04 BA13 BF06 2H086 BA02 BA59

Claims (19)

[Claims] 1. An ink discharge port for discharging ink, an ink storage section communicating with the ink discharge port and storing an amount of ink corresponding to one discharge, and an ink jet corresponding to the ink storage section An ink jet recording method for performing recording using an ink jet head provided with a plurality of sets of ejection elements, wherein ink is supplied from the ink ejection port to only an arbitrary portion corresponding to an image pattern of the ink jet head, An ink jet recording method comprising forming an image by discharging ink. 2. The ink jet recording method according to claim 1, wherein the ink is ejected by simultaneously driving all the elements. 3. The method according to claim 1, wherein the ejection of the ink is performed by performing ejection drive in a plurality of times in a time series.
The ink-jet recording method as described above. 4. An ink supply to only an arbitrary portion corresponding to an image pattern, wherein the ink storage unit and the ink-jet ejection element or a peripheral portion thereof are converted from ink-phobic to ink-philic by a photocatalytic reaction or a photochromic reaction. 2. The ink-jet recording method according to claim 1, wherein the method is performed by arranging an ink in the ink-philic portion. 5. The photocatalytic reaction is carried out by using a substance selected from the group consisting of titanium oxide, zinc oxide, tin oxide, tungsten oxide, bismuth oxide, iron oxide, silicon oxide and strontium titanate alone or in an image carrier. 5. The ink jet recording method according to claim 1, wherein the material is irradiated with light to cause a reaction. 6. The photocatalytic reaction includes visible light, ultraviolet light,
5. The ink jet recording method according to claim 1, wherein one of an excimer laser, a carbon dioxide laser, and a blue semiconductor laser is used. 7. An ink discharge port for discharging ink, an ink storage section communicating with the ink discharge port and storing an amount of ink corresponding to one discharge, and an ink jet corresponding to the ink storage section. An ink jet recording method for performing recording using an ink jet head provided with a plurality of sets of discharge elements, wherein ink is supplied to the ink jet head from the ink discharge port, and ink is supplied only to an arbitrary portion corresponding to an image pattern. And forming an image by ejecting the remaining ink. 8. The ink jet recording method according to claim 7, wherein the ink is discharged by simultaneously driving all the elements. 9. The method according to claim 7, wherein the ink is ejected in a plurality of times in chronological order.
The ink-jet recording method as described above. 10. An ink remaining on only an arbitrary portion corresponding to an image pattern is irradiated with light to an ink removing member that changes from ink-phobic to ink-philic by a photocatalytic reaction, so that only the arbitrary portion becomes ink-philic. 10. The ink-jet recording method according to claim 7, wherein the ink is removed in the ink-philic region, and the ink is left in the image pattern. 11. The photocatalytic reaction is performed by using a substance selected from the group consisting of titanium oxide, zinc oxide, tin oxide, tungsten oxide, bismuth oxide, iron oxide, silicon oxide and strontium titanate alone or in an image carrier. The method according to any one of claims 7 to 10, wherein the material is irradiated with light to cause a reaction. 12. The ink jet recording method according to claim 11, wherein the photocatalytic reaction uses any one of visible light, ultraviolet light, excimer laser, carbon dioxide laser, and blue semiconductor laser. 13. An ink discharge port for discharging ink, an ink storage section communicating with the ink discharge port and storing an amount of ink corresponding to one discharge, and an ink jet corresponding to the ink storage section. An ink jet recording apparatus that performs recording using an ink jet head provided with a plurality of sets of ejection elements. 14. The ink jet recording apparatus according to claim 13, wherein, if the depth of the ink discharge port is H and the diameter is R, then H <R / 2. 15. When the shape of the ink ejection port is a polygon such as a triangle or a square, the depth of the ink ejection port is set to H.
14. The ink jet recording apparatus according to claim 13, wherein H <CR is satisfied, where CR is a radius of curvature of the ink droplet generated from the ink ejection port. 16. The ink jet recording apparatus according to claim 13, further comprising a suction cleaning mechanism for cleaning a surface of the ink jet head including the ink discharge ports. 17. An ink jet recording apparatus according to claim 13, wherein said ink jet head is a rotary roller type or a flat type. 18. When printing a multi-tone image,
14. The ink jet recording apparatus according to claim 13, wherein a minimum necessary kind of ink or an ink jet head and its peripheral device system are used. 19. The apparatus according to claim 13, wherein the ink-jet discharge element has a heat energy generating element for generating heat energy sufficient to discharge the ink.
19. The ink jet recording apparatus according to any one of 18.