JP3029516B2 - Ink jet recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in an ink jet recording apparatus.

[0002]

2. Description of the Related Art Ink jet recording is much higher definition than conventional screen printing, and can print a high quality design with gradation. In addition, the use of a multi-nozzle head having hundreds to thousands of nozzles provides a certain level of productivity.

[0003]

[Problems to be solved by the invention]

1) However, ink having low viscosity (= thin) must be used due to the property of recording with ink ejected from a thin inkjet nozzle. Therefore, dark designs cannot be recorded. Spraying a large amount of ink can make it thicker, but it bleeds on the fabric to create a beautiful design.

[0004] 2) Since a number of nozzles are used in parallel, unevenness may occur depending on the characteristics specific to the nozzles.
It is difficult to form a defect-free image with recorded streaks, white streaks due to whimsical non-ejection, and the like. This is a major problem for industrial machines that produce tens of meters and hundreds of meters at a stretch in continuous operation.

[0005] 3) A pale color is expressed by sparsely adhering ink droplets, but the image is rough. In particular, if the nozzle diameter is increased to avoid the disadvantage 2), and the ink droplets are increased, this means that the resolution is reduced, and the roughness becomes remarkable.

[0006] 4) Some treatment agents are unstable with respect to the cloth, so some of them have a remarkable effect when applied immediately before recording, but such agents cannot be used in conventional processes.

[0007]

According to the present invention, ink is ejected.
Relative to the recording medium
Main scanning for scanning and ink jetting of the recording medium for each main scanning
In a direction different from the main scan relative to the recording section.
Recording is performed by repeatedly performing sub-scanning that conveys a predetermined amount.
An ink jet recording apparatus, wherein the sub-scanning direction is
In the main scanning direction at a predetermined recording width.
A first inkjet recording unit for performing recording on the
This position is located on the downstream side when viewed in the inspection direction.
A second inkjet recording unit for recording in the inspection direction;
The first inkjet recording unit and the second inkjet
And a predetermined position when viewed in the sub-scanning direction.
Having a space portion having a width longer than the recording width of the first ink.
Recording unit recorded on recording medium by jet recording unit
A drying unit for causing drying of the recording area including the minute,
Recording was performed by the first inkjet recording unit.
Thereafter, the recording area where the ink is dried by the drying section
Further use of the second inkjet recording unit for the area
And recording control means for performing recording.
Is intended to symptom, 1) after allowed through once recording cloth to a drying step, by further superimposing recording, to allow bleeding without dark (almost doubled in concentration) recording, 2) performs the serial scan In this case, the connecting line is eliminated by dividing the overlapped recording several times and feeding the divided lines.

[0008] 3) In order to form one row of pixels or one pixel, the head is relatively displaced and the recording is executed by superposition printing using different nozzles, thereby eliminating unevenness, warping streaks and white streaks. 4) The light color is superimposed on the transparent ink for fading and recorded to have a predetermined density (lightness) on the cloth, so that the roughness is eliminated. Even if a large amount of transparent ink is recorded, a high-definition image can be realized without bleeding since the next recording step is performed after the subsequent drying step.

5) The pretreatment agent is recorded at the preprocessing station immediately before recording or at the head of the recording section, and the postprocessing agent is recorded at the end of the last recording section or at the postprocessing station to enhance the processing effect.

[0010] In the present specification, "recording" includes the meaning of "textile printing", and means that an image is widely applied to a recording medium such as cloth or paper.

[0011]

According to the present invention, it is possible to perform print recording in which the characteristics of textile printing by ink jet recording, that is, high definition and high gradation, are kept as they are, and there is little blur, dark spots, streaks, connecting streaks, and roughness.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing the basic configuration of an ink jet recording apparatus according to the present invention. This ink jet recording apparatus is configured as a system,
An image reading device 1 that reads an original image created by a designer or the like and converts the original image into original image data represented by electric signals, an image processing unit that takes in the original image data from the image reading device 1, processes the original image data, and outputs it as image data. 2. An image recording unit 3 for recording on a recording medium such as a cloth based on the image data created by the image processing unit 2. In the image reading device 1, an original image is read by a CCD image sensor. In the image processing unit 2, an ink jet recording unit A for ejecting four color inks of magenta (abbreviation M), cyan (abbreviation C), yellow (abbreviation Y), and black (abbreviation Bk), which will be described later, from the input original image data. -2 (FIG. 2) is generated. When creating data, image processing to reproduce the original image with ink dots, color scheme to determine color tone, layout modification, processing of design size such as enlargement, reduction, etc.
A choice is made. In the image recording unit 3, recording is performed by the inkjet recording unit A-2. The ink jet recording unit A-2 performs recording by causing minute ink droplets to fly toward a recording medium and attaching the ink droplets to the recording medium.

FIG. 3 is a perspective view showing a printing unit of the ink jet recording apparatus used in the present invention.

First, the ink jet printing section is roughly classified into a frame 6, two guide rails 7 and 8, an ink jet head 9 and its moving carriage 10, an ink supply device 11 and its moving carriage 12, and a head recovery device 13. And a transmission system 5. The ink jet head 9 (hereinafter, simply referred to as a head) includes a plurality of nozzle rows and a conversion device for converting an electric signal into ink ejection energy, and a nozzle corresponding to the image signal sent from the image processing unit 2. A mechanism is provided for selectively discharging ink from the rows.

The head is a recording head that discharges ink by using thermal energy, and includes a thermal energy converter for generating thermal energy to be applied to the ink. A head that causes a state change in the ink by the applied heat energy and discharges the ink from the discharge port based on the state change is preferably used.

The ink supply device 11 stores ink,
This is for supplying a required amount of ink to the head, and includes an ink tank and an ink pump (not shown). The main body and the head 9 are connected by an ink supply tube 15, and are normally automatically supplied to the head 9 by an amount discharged from the head by a capillary action. In addition, at the time of a head recovery operation described later, ink is forcibly supplied to the head 9 using an ink pump.

The head 9 and the ink supply device 11 are mounted on a carriage 10 and a carriage 12, respectively, and are configured to reciprocate along guide rails 7 and 8 by a driving device (not shown).

The head recovery device 13 is provided at a position where the head 9 can be opposed to the head 9 at a home position (standby position) of the head 9 in order to maintain the ink ejection stability of the head. Specifically, the following operation is performed.

First, capping of the head 9 is performed at the home position in order to prevent evaporation of ink from the nozzles of the head 9 during non-operation (capping operation).
Alternatively, an operation of pressurizing the ink flow path in the head using an ink pump to forcibly discharge ink from the nozzles to discharge bubbles, dust, and the like in the nozzles before starting image recording (pressure recovery operation). Alternatively, it performs a function of collecting ink discharged when performing an operation of forcibly discharging and discharging ink from the nozzles (a suction recovery operation).

The transmission system 5 includes a power supply section and a control section for performing sequence control of the entire ink jet recording section.
Each time the head 9 moves in the main scanning direction along the guide rail and a predetermined length of recording is performed, the cloth 36 is conveyed by a predetermined amount in the sub-scanning direction (arrow B direction) by a conveying device (not shown), and image formation is performed. Will be done. In the figure, a hatched portion 17 indicates a portion where recording has been completed.

As the recording head 9, an ink jet recording head for monochromatic recording, a plurality of recording heads for recording with different color inks for color recording, or a plurality of recording heads for recording with the same color but different density inks are used. A recording head or the like can be used.

The recording means and the ink tank may be of a cartridge type in which a recording head and an ink tank are integrated, or a recording head and an ink tank which are separated and connected by an ink supply tube. It can be applied regardless.

Further, by implementing the present invention in the recording apparatus of the following embodiment, a high-quality image can be obtained even on a recording medium having extremely low water absorption.

FIG. 2 is a schematic diagram showing an outline of an image recording section particularly preferable for the present invention. This recording apparatus is roughly divided into a feeding section B for feeding a recording medium such as a roll-shaped cloth which has been subjected to a pre-treatment for printing, and a feeding section B for feeding the fed cloth precisely. It comprises a main unit A for printing and a winding unit C for drying and winding the printed fabric. The main unit A further includes a precision feeding unit A-1 for fabric containing a platen and an ink jet recording unit A.
-2.

The operation of this apparatus will be described below by taking as an example a case where printing is performed using a pretreated fabric as a recording medium.

The pretreated roll-shaped cloth 36 is sent out from the supply section B and sent to the main body. A thin endless belt 37, which is precisely step-driven, is wound around a drive roller 47 and a winding roller 49 in the main body. The driving roller 47 is a high-resolution stepping motor (not shown)
And the belt is stepped directly by the step amount. The fed cloth 36 is pressed by the pressing roller 40 and adhered to the surface of the belt 37 backed up by the winding roller 49.

The cloth 36 that has been step-fed by the belt is localized in the first printing unit 31 by the platen 32 on the back of the belt and printed by the ink jet head 9 from the front side. Each time printing of one line is completed, the printing paper is stepped by a predetermined amount, and then heated by the heating plate 34 from the back of the belt and heated air duct 35
Dry by hot air from the surface, which is supplied / discharged by Subsequently, in the second printing section 31 ', the overprinting is performed in the same manner as in the first printing section.

The printed fabric is peeled off, dried again in the post-drying section 46 similar to the above-described heating plate and hot air duct, guided to the guide roll 41 and taken up by the take-up roll 4.
8 Then, the wound fabric is removed from the present apparatus, and is subjected to a post-treatment process such as color development, washing, and drying in a batch process to become a product.

Next, details of the vicinity of the ink jet recording section A-2 will be described with reference to FIG.

In a preferred embodiment, the information is recorded by thinning out the number of dots by the head of the first printing section, and after the drying step, the information is thinned out in the first printing section by the head of the second printing section. Ink droplets are ejected to supplement information.

In FIG. 4, a cloth 36 as a recording medium is shown.
Is affixed to a belt so that it is stepped upward in the figure. The first print section 31 in the lower part of the figure has a first carriage 44 on which eight inkjet heads for spot colors S1 to S4 are mounted in addition to Y, M, C, and Bk. The ink jet head (recording head) in this example uses an element having a device that generates thermal energy that causes film boiling of the ink as energy used to discharge the ink.
An array of 128 ejection ports with a density of dpi (dot / inch) is used.

At the downstream side of the first printing unit, a drying unit 45 including a heating plate 34 for heating from the back of the belt and a hot air duct 35 for drying from the front side is provided. The heat transfer surface of the heating plate 34 is pressed against a strongly tensioned endless belt 37, and the conveying belt 37 is strongly heated from the back by high-temperature and high-pressure steam passing through the hollow inside. Conveyor belt 37
Heats the attached fabric 36 directly and effectively by heat conduction. Fins 34 'for collecting heat are provided on the inner side of the heating plate surface so that heat can be efficiently concentrated on the back surface of the belt. The side not in contact with the belt is covered with a heat insulating material 43 to prevent loss due to heat radiation.

On the front side, by blowing hot dry air from the downstream supply duct 30, the cloth being dried is exposed to lower humidity air to enhance the effect. Then, the air flowing in the opposite direction to the direction of transport of the fabric and sufficiently containing water is sucked from the suction duct 33 on the upstream side by a much larger amount than the amount of the sprayed air. Prevents condensation on mechanical devices. The hot air supply source is located on the back side of FIG. 4, and suction is performed from the near side. The pressure difference between the outlet 38 and the suction port 39 facing the fabric is uniform over the entire area in the longitudinal direction. It is made to become. The air blast / suction unit is offset downstream with respect to the center of the backside heating plate so that the air hits the well heated area. As a result, the first printing unit 31 strongly dries a large amount of water in the ink including the thinning liquid received by the cloth.

Downstream (upper) of the second printing unit 3
1 ', and a second print section is formed by a second carriage 44' having the same configuration as that of the first carriage.

Next, a specific example of the ink jet textile printing will be described. As described above, FIG. 2 is a diagram showing the configuration of an embodiment suitable for printing. As shown in FIG. 2, after passing through the ink-jet printing process, it is dried (including natural drying). Subsequently, a step of diffusing the dye on the fabric fiber and reacting and fixing the dye to the fiber is performed. By this step, it is possible to obtain sufficient color developability and fastness due to fixation of the dye.

This diffusion and reactive fixing step may be a conventionally known method, for example, a steaming method. In addition,
In this case, the fabric may be subjected to an alkali treatment before the printing step.

Thereafter, in a post-treatment step, unreacted dye and substances used in the pre-treatment are removed. Finally, the record is completed through an orderly finishing process such as defect correction and ironing.

As recording media, cloth, wallpaper, paper, OH
P film and the like. In particular, the present invention is suitable for low-water-absorbing recording media such as cloth and wallpaper.

In the present invention, a fabric is a material,
Includes all woven, non-woven and other fabrics, regardless of weave or knit.

In the present invention, the wallpaper includes paper, cloth, and a wall sticking material made of a synthetic resin sheet such as polyvinyl chloride.

In particular, as a fabric for ink-jet printing, (1) the ink can be colored to a sufficient concentration;
(2) high ink dyeing rate; (3) quick drying of the ink on the fabric; (4) less occurrence of irregular ink bleeding on the fabric; And high performance such as excellent transportability. In order to satisfy these required performances, the cloth can be pre-treated beforehand as necessary. For example, Japanese Patent Application Laid-Open No. Sho 62-53492 discloses fabrics having an ink receiving layer, and Japanese Patent Publication No. 3-46589 proposes a fabric containing a reduction inhibitor or an alkali substance. . As an example of such a pretreatment, there can be mentioned a treatment in which a cloth contains a substance selected from an alkaline substance, a water-soluble polymer, a synthetic polymer, a water-soluble metal salt, urea and thiourea.

Examples of the alkaline substance include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide;
Examples thereof include amines such as mono, di, and triethanolamine, and alkali metal salts of carbonic acid or bicarbonate such as sodium carbonate, potassium carbonate, and sodium bicarbonate. Further, there are organic acid metal salts such as calcium acetate and barium acetate, ammonia and ammonia compounds. Further, sodium trichloroacetate which becomes an alkaline substance under steaming and dry heat may be used. Particularly preferred alkaline substances include sodium carbonate and sodium bicarbonate used for dyeing reactive dyes.

Examples of the water-soluble polymer include starch substances such as corn and wheat; cellulosic substances such as carboxymethylcellulose, methylcellulose and hydroxyethylcellulose; sodium alginate;
Locust bean gum, tragacanth gum, guar gum,
Examples thereof include polysaccharides such as tamarind seeds, protein substances such as gelatin and casein, tannin-based substances, and natural water-soluble polymers such as lignin-based substances.

Examples of the synthetic polymer include polyvinyl alcohol-based compounds, polyethylene oxide-based compounds, acrylic acid-based water-soluble polymers, and maleic anhydride-based water-soluble polymers. Among them, polysaccharide polymers and cellulose polymers are preferable.

Examples of the water-soluble metal salt include compounds which form typical ionic crystals and have a pH of 4 to 10, such as halides of alkali metals and alkaline earth metals. Representative examples of such compounds include, for example, NaCl, Na ₂ S
O ₄ , KCl and CH ₃ COONa, and the like, and as the alkaline earth metal, CaCl ₂ and MgC
l _2, and the like. Among them, salts of Na, K and Ca are preferred.

The method of incorporating the above substances and the like into the fabric in the pretreatment is not particularly limited, and examples thereof include a commonly used dipping method, pad method, coating method, spray method and the like.

Further, the printing ink applied to the fabric for ink-jet printing simply adheres to the fabric when applied to the fabric, so that a step of reactively fixing the dye to the fiber (dyeing step) is performed. Is preferred. Such a reaction fixing step may be carried out by a conventionally known method, for example, a steaming method, an HT steaming method, a thermofix method, or an alkaline pad steam method or an alkaline blotch steam method when a cloth which has been previously alkali-treated is not used. ,
Examples include an alkali shock method and an alkali cold fix method.

Further, the removal of unreacted dye and the substance used in the pretreatment can be carried out by washing after the above-mentioned reaction fixing step in accordance with a conventionally known method. In addition, it is preferable to use the conventional fix treatment in combination with the washing.

The overprinting performed by the ink jet printing apparatus of this embodiment will be described with reference to FIG.

As described above, eight heads are integrated in each printing unit. However, in this figure, for simplicity, only one head is shown in the head row of the printing unit.

In this embodiment, the first printing section 31 located on the upstream side first performs serial printing at a density of 1/4 of a predetermined final printing density (ejection amount per unit area), and then performs printing at a printing width w of 1/4. / 2 in the direction of ↑, and 1 more
Serial recording is performed at a density of / 4. The overlapped portion means that recording was performed at half the final recording density. This is repeated, and the pattern is recorded at a density of 1/2 of the final recording density in the first printing section. Next, while sequentially passing through the drying unit 45, the drying is performed as described above.
Next, the same overprinting as that of the first printing unit is performed in the second printing unit 31 'downstream thereof. At the same time, recording is performed at 1/4 density × 4 times of overstrike = 1, that is, at a predetermined recording density.

It should be noted here that the "predetermined recording density" is almost doubled by using the drying unit 45 between the first and second printing units (using thinner ink together). ), And thus can be recorded with sufficient density.

The relationship between the position of the connection between the scans of the first print unit 31 and that of the second print unit 31 'is as follows. In the first and second printing sections, the connection can be made at a half pitch of the recording head, but in this embodiment, the connection is made so as not to overlap each other.
In the middle of the seam of the first record and just in the middle of the seam, the second
The joint of the print section is positioned. {Relationship between the distance d between the first print section and the second print section and the head width w is d = (n + 1/4) w n: a natural number} Noteworthy here is the problem of stitches between scans. is there.

In a serial scan in which printing is performed at 100% density at a time, 100% density should be replaced with 0% density due to gaps and overlaps caused by various errors related to the amount of cloth fed and ink bleeding. White streaks or 200% dark streaks and image defects. However, according to the embodiment of the present invention, one record is one time.
/ 4 = only 25% of the record, and on top of that, it is covered in triple with the correct density (= not connected)
What should be 100% density is slightly faint to 75% density and only slightly thicker to 125% density. In addition, the width of this streak is approximately halved because the amount of error is halved. The combination of the two virtually eliminates any tethers.

In addition, the streaks caused by the writhing and the non-ejection occurring at a whim are similarly covered by other normal three-time overlapping recording.

That is, according to this embodiment, since the head of the same color passes four times at one pixel position, the same color can be superimposed up to 4 dots at this pixel position. In addition, after the two dots are overlaid, they are dried and the next overstriking is performed, so that there is no bleeding. That is, multi-valued expression of five values (gray scale) of 0, 1, 2, 3, 4, can be performed instead of the binary expression of hitting / not hitting of the normal ink jet. In this embodiment, there are five color heads except for black, so that one pixel has 5 tones to the fifth power = 312.
Five colors can be expressed. In this calculation, a maximum of 4 dots × 5 colors = 20 dots is applied to one pixel. In addition, since it is 10 to 16 dots that can be printed without bleeding into one pixel even with a drying process, 3
Not even 125 colors. However, perfect gradation reproduction can be performed by superimposing the error diffusion method on this, and further by the effect of the thinning solution. Second Embodiment Another print unit / dry unit (preprint unit / predry unit) is provided upstream of the first print unit in the above embodiment. In this printing section, a pretreatment agent for fabric dyeing is applied according to the recording pattern instead of ink. In the printing section, different types of processing agents are supplied to the respective heads so as to be adaptable to various materials of the fabric. After the pretreatment agent is fixed in the pre-drying unit, it is recorded in the downstream first and second printing units where the pretreatment agent has been treated with the treatment agent, as in the first embodiment. This prevents waste of unnecessary processing agents and reduces the amount of washing-out agents in post-processing. (This is an ecological technology that does not use inkjet dyeing itself, which is dyed paste = most of it is washed out and discarded.
Make it even more effective. This pre-recording section does not require much resolution. With a resolution half that of the first and second printing units, a design that does not cause non-discharge and that has enhanced processing agent resistance can be obtained.

Finally, another print section (post-print section) can be provided to further enhance the post-processing effect. Third Embodiment The recording method in the first / second printing units is not necessarily limited to the above-mentioned method (overlapping method / number of connection positions). The first and second recordings are divided into a plurality of times and dividedly fed by one recording width. At least a drying step is included in the steps, and the recording is performed repeatedly.
The point of the present invention is that the splicing positions in the print sections do not match.
Variations such as a configuration having two drying units and b) a configuration having three printing units / two drying units that are stacked twice are possible.

The method (a) further reduces unevenness and streaks.
The method b) achieves a higher concentration. Fourth Embodiment FIG. 6 is a diagram for explaining recording data recorded by sequential multi-scan.

In FIG. 6, each rectangular area surrounded by a dotted line corresponds to one dot (pixel).
In the case of dpi (dot / inch), the area of each rectangle is approximately (63.5 μm) ² . A portion indicated by a black circle is a portion where a dot is formed, and a portion where no black circle is present indicates a portion where recording is not performed. The ink jet head moves in the direction of arrow F, and ink is ejected from the ink ejection nozzle at a predetermined timing. This sequential multi-scan is performed in order to correct variations in the size of ink droplets ejected from each nozzle and variations in density between the nozzles caused by variations in the ink ejection direction, and the same line (head moving direction) Is recorded by a plurality of nozzles. By forming one line with a plurality of nozzles in this manner, density unevenness is reduced by utilizing the randomness of the nozzle characteristics of each inkjet head. In other words, sequential scanning by twice scanning
In the case of multi-scan, printing is performed using the upper half of the inkjet head in the first scan, and printing is performed using the nozzle in the lower half of the inkjet head in the second scan.

FIGS. 7 and 8 show an example of recording by the sequential multi-scan.

For example, when recording the data shown in FIG. 6, first, as shown in FIG. 7, only the odd-numbered recording data of the data generated in the moving direction of the ink jet head is transferred to the upper half of the ink jet head. Record with the nozzle. Next, the ink jet head (carriage) is returned to the home position direction, and the cloth 36 is fed by half the width of the ink jet head, and as shown in FIG. Recording is performed using the nozzle in the lower half of the head. Thus, the data as shown in FIG. 6 is recorded on the cloth 36 by the two scans.

FIG. 9 shows an example of printing by ordinary two-time multi-scan. Areas (lower 1) 701, (lower 2) 7 printed by the inkjet head of the first print unit 31
02, (lower 3) 703, the second print unit 31 '
(Top 1) 7
04, (top 2) 705, and (top 3) 706.

The cloth feeding direction is as shown by the arrow in the figure.
The single step feed amount of No. 6 corresponds to the recording width of the inkjet head. As is apparent from FIG. 9, all of the recorded areas are the upper half of the inkjet head of the second print unit 31 'and the lower half of the inkjet head of the first print unit 31, or the second print unit 31. ′
Lower half of the inkjet head and the first print unit 3
Recording is performed using the upper half of one inkjet head. Here, the data recorded by each ink jet head is thinned out as shown in FIGS. 7 and 8 described above, and as a result of being superimposed and recorded by these two ink jet heads, the print density indicated by 707 is reduced. can get.

The recorded material subjected to the post-processing steps described above is thereafter cut into a desired size, and the cut pieces are subjected to a process for obtaining a final processed product such as sewing, bonding, welding, or the like. To obtain clothes such as dresses, dresses, ties, swimwear, duvet covers, sofa covers, handkerchiefs, curtains and the like. Many methods for processing cloth by sewing or the like to produce clothing and other daily necessities are described in a number of well-known books, such as “Latest Knit Sewing Manual”: Published by Seny Journal, and monthly magazine “Soen”: Published by Bunka Publishing Bureau. Have been.

The drying section is not a forced air blowing means or the like, but a predetermined time for naturally drying the ink for a time required for the recording medium to be transported from the first inkjet recording section to the second inkjet recording section. May be provided.

The present invention provides an excellent effect in an ink jet recording head and a recording apparatus, in which a flying droplet is formed by utilizing thermal energy even in an ink jet recording method, and recording is performed.

The typical structure 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 can be applied to both the so-called on-demand type and the continuous type. In particular, in the case of the on-demand type, it is arranged corresponding to the sheet or the liquid path holding the liquid (ink). By applying at least one drive signal corresponding to the recording information and providing a rapid temperature rise exceeding nucleate boiling to the electrothermal transducer, heat energy is generated in the electrothermal transducer, and the recording head is driven. This is effective because film boiling occurs on the heat-acting surface, and as a result, bubbles in the liquid (ink) corresponding to this drive signal on a one-to-one basis can be formed. By discharging the liquid (ink) through the discharge opening by the growth and contraction of the bubble, at least one droplet is formed. 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. In addition,
US Patent No. 4 of the invention relating to the rate of temperature rise of the heat acting surface
If the conditions described in the specification of Japanese Patent No. 313124 are adopted, more excellent recording can be performed.

As the configuration of the recording head, in addition to the combination of a discharge port, a liquid path, and an electrothermal converter (a linear liquid flow path or a right-angle liquid flow path) as disclosed in the above-mentioned respective specifications, The present invention also includes a configuration using U.S. Pat. No. 4,558,333 or U.S. Pat. No. 4,459,600, which discloses a configuration in which a heat acting portion is arranged in a bending region.

In addition, Japanese Unexamined Patent Publication No. 59-123670 discloses a configuration in which a common slit is used as a discharge portion of an electrothermal transducer for a plurality of electrothermal transducers, and absorbs pressure waves of thermal energy. The present invention is also effective as a configuration based on JP-A-59-138461, which discloses a configuration in which an opening corresponds to a discharge unit.

Further, as a full-line type recording head having a length corresponding to the maximum recording medium width that can be recorded by the recording apparatus, a combination of a plurality of recording heads as disclosed in the above-mentioned specification is used. Either a configuration that satisfies the length or a configuration as one integrally formed recording head may be used, but the present invention can more effectively exert the above-described effects.

In addition, the print head is replaceable with a print head of a replaceable chip type, which can be electrically connected to the main body of the apparatus or supplied with ink from the main body of the apparatus, or is integrated with the print head itself. The present invention is also effective when a cartridge type recording head provided with an ink tank is used.

It is preferable to add recovery means for the printhead, preliminary auxiliary means, and the like provided as components of the printing apparatus of the present invention since the effects of the present invention can be further stabilized. If you list these specifically,
Capping means, cleaning means, pressurizing or suction means for the printhead, preheating means using an electrothermal transducer or another heating element or a combination thereof, and a preliminary ejection mode for performing ejection other than recording Is also effective for performing stable recording.

In the embodiments of the present invention described above, the ink is described as a liquid. However, even if the ink solidifies at room temperature or below, it may be softened at room temperature or liquid, or In the above-described ink-jet method, it is general to control the temperature of the ink itself within a range of 30 ° C. or more and 70 ° C. or less so that the viscosity of the ink is in a stable ejection range. It is sufficient if the ink is in a liquid state.

In addition, the temperature rise due to heat energy is positively prevented by using it as energy for changing the state of the ink from the solid state to the liquid state, or the ink is solidified in a standing state for the purpose of preventing evaporation of the ink. Either ink may be used, or in any case, the ink may be liquefied by application of heat energy according to the recording signal and ejected as liquefied ink, or may already start to solidify when reaching the recording medium. In the present invention, the use of ink having a property of being liquefied for the first time by heat energy is also applicable. In such a case, the ink is disclosed in JP-A-54-5684.
No. 7 or Japanese Patent Application Laid-Open No. 60-71260, while being held as a liquid or solid substance in a concave portion or a through hole of a porous sheet, and facing an electrothermal converter. It is good also as a form. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

Further, as a form of the recording apparatus according to the present invention, in addition to those provided integrally or separately as an image output terminal of an information processing device such as a word processor and a computer, a copying apparatus combined with a reader and the like, May take the form of a facsimile machine having a transmission / reception function.

[0078]

According to the present invention, the printing characteristics obtained by ink jet recording, ie, high definition and high gradation, can be obtained as they are, and the print recording can be obtained without any bleeding, with dark and vivid, almost no unevenness, streaks, streaks, and roughness. To play.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a basic configuration of the present invention.

FIG. 2 is a diagram illustrating a configuration of an image recording unit according to an embodiment of the present invention.

FIG. 3 is a perspective view showing a print unit according to the embodiment.

FIG. 4 is a diagram showing the vicinity of an ink jet recording unit according to the embodiment.

FIG. 5 is an explanatory diagram for overprinting of an embodiment.

FIG. 6 is a diagram for explaining recording by sequential multi-scan.

FIG. 7 is a diagram for explaining recording by sequential multi-scan;

FIG. 8 is a diagram for explaining recording by sequential multi-scan;

FIG. 9 is a diagram showing a recording example by sequential multi-scan.

[Explanation of symbols]

 Reference Signs List A main unit A-1 precision feeding unit A-2 ink jet recording unit B feeding unit C winding unit 1 image reading device 2 image processing unit 3 image recording unit 9 ink jet head 10 carriage 11 ink supply device 12 carriage 13 head recovery device Reference Signs List 30 supply duct 31 first printing section 31 'second printing section 33 suction duct 34 heating plate 35 hot air duct 36 cloth 37 belt 38 outlet 39 suction port 40 pressing roller 44 first carriage 44' second carriage 45 drying section 46 Post-drying section 47 Drive roller 49 Winding roller

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI D06P 5/00 111 B41J 29/00 GH (72) Inventor Masatoshi Katsui 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Examiner in Japan Co., Ltd. Teruki Yumoto (56) References JP-A-2-252564 (JP, A) JP-A-2-208056 (JP, A) JP-A-63-317350 (JP, A) (58) Survey Field (Int.Cl. ⁷ , DB name) B41J 2/01 B41J 2/05 B41J 2/205 B41J 29/00 B41M 5/00 D06P 5/00 111

Claims (8)

(57) [Claims] A main scanning section for scanning an ink jet recording section for discharging ink relative to a recording medium; and a main scanning section.
Each time the recording medium is
Sub-scanning, which carries a predetermined amount in a direction different from the main scanning,
An ink jet recording apparatus that performs recording by performing repeatedly, and is located on the upstream side when viewed in the sub-scanning direction, and has a predetermined recording width.
A first inkjet recording unit that performs recording in the main scanning direction; and a first inkjet recording unit that is located downstream on the sub-scanning direction and has a predetermined recording width.
A second inkjet recording unit that performs recording in the main scanning direction; and a second inkjet recording unit that is located between the first inkjet recording unit and the second inkjet recording unit.
A drying unit having a space portion having a width longer than a predetermined recording width, and causing a drying of a recording region including a recording portion recorded on a recording medium by the first inkjet recording portion; Recording control means for performing recording using the second ink jet recording unit on the recording area where ink has been dried by the drying unit after recording is performed by the ink jet recording unit. Characteristic inkjet recording device. 2. The printing apparatus according to claim 1, further comprising: a pre-processing unit provided upstream of the recording of the first ink jet recording unit for adhering a pre-processing agent to the recording medium. Inkjet recording device. 3. The ink-jet recording apparatus according to claim 1, wherein the recording control means performs multi-value recording on the recording area using the first ink-jet recording unit and the second ink-jet recording unit. Recording device. 4. The ink jet recording apparatus according to claim 1, wherein said ink jet recording section has a plurality of recording heads, at least one of which is a recording head which discharges a lighter color ink than the other. apparatus. Wherein said drying unit, according to claim 1 Symbol mounting of the ink jet recording apparatus comprising an air blowing means provided on the recording surface of the recording medium. 6. A drying unit provided on the back side of the recording medium and for promoting drying of ink in a recording area including a recording portion recorded on the recording medium by the first inkjet recording unit. the ink-jet recording apparatus according to any one of claims 1 to 5, characterized in that. 7. The recording control unit causes the first inkjet recording unit to perform recording by thinning out a part of image data to be recorded, and further performs recording on the recording area where drying has occurred by the drying unit. to perform the recording of the image data thinned that were not recorded by the first ink jet recording unit using the second ink jet recording unit, one of the claims 1 to 6, characterized in that to complement the recording An inkjet recording apparatus according to any one of the above. 8. The first ink jet recording section and the second ink jet recording section each include a recording head for discharging ink, and the recording head is a recording head for discharging ink using thermal energy. The inkjet recording apparatus according to any one of claims 1 to 7 , wherein the inkjet recording head includes a thermal energy converter for generating thermal energy applied to the ink.