JPH07314661A - Ink jet recording method and recorder - Google Patents

Abstract

PURPOSE:To provide means for improving the recording quality level by preventing the decrease of the density of ink due to impregnation of a recording medium with the ink or oozing of ink to the periphery of a recorded image in an ink jet recorder. CONSTITUTION:A waveguide 111 connected to a magnetron 103 as microwave generating means is provided adjacent to a recording head 102. As a fixing unit of the structure having a metal at the opposite side to the head 102 to a recording medium 106, the microwave is irradiated to the recorded ink at least without several 10msec immediately after the ink is adhered to the medium 106.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fixing method for ink jet recording in which ink droplets are adhered and fixed on a recording medium to form characters and images, and an ink jet recording apparatus using the method.

Further, the present invention relates to a color ink jet recording method capable of recording a color image clearly and with high density, and more specifically, yellow (Y), magenta (M),
The present invention relates to a fixing method for a color inkjet recording apparatus using color inks such as cyan (C), green (G), red (R), and blue (B), and black (Bk) ink.

The present invention is applicable to paper, cloth, non-woven fabric, and OHP.
It can be applied to all devices that use a recording medium such as paper, and specific applicable devices include a printer, a copying machine, and a facsimile.

[0004]

2. Description of the Related Art This type of ink jet recording is widely used in various devices such as printers, copiers and facsimiles because of its features such as low noise, low operating cost, easy miniaturization of device and easy colorization. Has been done. Color inkjet recording uses three color inks of cyan (C), magenta (M), and yellow (Y), and further,
Color recording is performed using four color inks with black (Bk) added.

In the conventional ink jet recording of this kind, it was necessary to use a special paper having an ink absorbing layer in order to obtain a color image of high color development without ink bleeding. Therefore, a method of giving a recording aptitude to "plain paper" which is used in a large amount in a printer or a copying machine has been put into practical use. However, at present, the recording quality on these "plain paper" remains at an extremely insufficient level. The factors that can be cited are
It is the fixing of the ink attached to the recording medium.

For high density recording, it is necessary to increase the amount of ink adhered per unit area, and for high speed recording, it is necessary to increase the amount of ink adhered per unit time. Both of these make the conditions for fixing the ink on the recording medium disadvantageous. There is a problem that the ink overflows into the non-recording area, or the ink of the previous recording medium adheres to the edge or the rear surface of the next recording medium during continuous recording. Furthermore, in color inkjet recording,
Ink bleeding between colors is likely to occur.

[0007]

Generally, when characters or images are recorded on a recording medium by this type of ink jet recording, a quick-drying ink having a high penetration speed into the recording medium is used. For this reason, the ink permeates into the inside of the recording medium, the density is lowered, and the so-called "feathering phenomenon" in which the ink slightly bleeds along the fibers of the paper around the recorded image area easily occurs. .

The present invention has been made in order to solve the problems in the prior art as described above, and it is possible to efficiently accelerate the fixing action of ink on a recording medium and to print from the desired area. The purpose is to minimize the spread, increase the recording density of the fixed ink, and enable high-quality recording without a feathering phenomenon.

Further, another object is to improve recording quality by adhering a larger amount of ink to improve recording density than before, and when another ink is recorded in an area where a certain ink is fixed. In order to prevent deterioration of recording due to mixing of inks with other inks to be recorded later, wrinkles of the recording medium after recording are eliminated, and the physical quality of the recording medium is improved. Especially.

In order to achieve these objects, a method of heating the platen on the rear surface at the recording position of this type of recording apparatus, a method of using a large heat radiation heater from the rear surface, and the like have been conventionally proposed. However, since these are methods of heating and fixing the ink through the recording medium, the fixing efficiency is limited. Further, the heat response of the fixing device is poor, and for example, a heating time of about 1 minute is required after recording is attempted.

On the other hand, Japanese Patent Application Laid-Open No. 55-107490 proposes and discloses a method of adhering ink to a recording medium and then sending the recording medium to a metal cylinder in which microwaves are concentrated to dry and fix it. However, according to this method, after the ink is recorded on the recording medium, the ink is dried at least several hundreds msec, and in some cases several seconds, and then the ink is dried at the desired position on the recording medium. Since it is dried after spreading to the outside and bleeding occurs, the sharpness of the edge part cannot be obtained, and since the ink has penetrated into the recording medium and dried, sufficient density can be obtained. There wasn't. Furthermore, in the case of a plurality of inks, since the inks are dried after bleeding occurs between the plurality of inks, the substantial effect of preventing bleeding cannot be obtained.

[0012]

Therefore, in the present invention, an ink jet recording in which a carriage equipped with a recording head for ejecting ink droplets records a recording area on a recording medium by a main scanning operation and a sub scanning operation. Method,
The carriage is provided with a means for generating a microwave, and the method for irradiating the recording medium immediately after recording with the microwave during the recording operation of the main scanning is adopted to achieve the above object. is there.

[0013]

According to the method of the present invention as described above, the recording medium has a waveguide for generating a microwave adjacent to the recording head, the waveguide being in communication with, for example, a magnetron, and the metallic body is provided on the opposite side of the recording medium from the recording head. As a fixing device having a structure having at least several tens of ink immediately after the ink is attached to the recording medium during recording.
Ink recorded within msec By irradiating with the microwave, the recording density of the stable ink is increased, the occurrence of the "feathering" phenomenon is prevented, the recording quality is improved, and other inks to be recorded after that. Since the "bleeding" between and is eliminated, the recording quality at the boundary is also improved.

[0014]

EXAMPLES The present invention will be described below in detail based on a plurality of examples: (Example 1) FIG. 1 is a schematic perspective view of an ink jet recording apparatus according to a first example of the present invention. . The recording medium 106 loaded in the recording apparatus is conveyed to the recording area of the recording head 102 by the feed roller 109. A metal platen 108 is provided below the recording medium 106 in the recording area. The carriage 101 is configured to be movable in a direction defined by the two guide shafts 104 and 105, and reciprocally scans the recording area. On the carriage 101, four color inks, a recording head 102 for ejecting these inks, and a small magnetron 103 are mounted. The four color inks are black (Bk), cyan (C), magenta (M), and yellow (Y). 1
Reference numeral 07 denotes a switch and a display panel for displaying various recording mode settings and the state of the recording apparatus.

FIG. 2 is an enlarged sectional view showing the recording head mechanism near the carriage 101 portion of the ink jet recording apparatus of this embodiment. The carriage 101 has a pair of pressing rollers 112, and the recording medium 1 is attached to the platen 108.
Press 06 to fix. Bk head and each Y, M, C
Between the heads, the magnetron 110 and the waveguide 1 ahead
There is 11. Further, a rotating propeller 114 is arranged in the same wave tube 111. This rotational power is the motor 115 above the magnetron 103.

The microwave generated by the magnetron 103 is diffusely reflected by the propeller 114 and the wall of the waveguide 111 in the waveguide 111, and the microwave is irradiated toward the recording medium 106. The waveguide 111 and the platen 108 have the same potential, and the platen 108 also reflects microwaves. The distance D between the waveguide 111 and the platen 108 is adjusted to be about 1 mm. This interval D is necessary to reduce the leakage of microwaves to the outside of the recording device and to improve the efficiency.

The thickness of the recording medium 106 is usually 100-4.
Since the recording medium 106 is pressed against the platen 108 by the pressing rollers 112, the ejection port 102 of the recording head 102 is further increased.
Since a is disposed at a position slightly retracted from the tip of the waveguide 111, the ejection port 102a does not come into contact with the recording medium 106.

When the carriage 101 moves in the direction of arrow A, first, Bk ink is recorded, and Bk is recorded by microwave.
Fix the ink. Then, C, M, and Y inks are recorded, respectively. The microwave is 2.45G in this embodiment.
A power of 180 W was applied at a frequency of Hz.

In particular, the Bk ink has less feathering but has a fixing property worse than the C, M and Y inks. Normally, when Bk ink is recorded on a sheet used in a copying apparatus called "plain paper", the ink on the surface of the sheet penetrates and fixes inside in about 2 to 6 seconds. By the fixing means, the fixing time is within 20 msec, and the fixing is performed before the ink spreads on the surface of the recording medium 106.

Here, the Bk ink ejection port and the C ink ejection port have an interval of 1 inch, and 360 dot ink droplets are recorded at a frequency of 10 kHz between them. in this case,
If the Bk ink is fixed within 360 msec, bleeding between colors does not occur with the C, M, and Y inks. Therefore, 20 msec is a sufficient time for this. Further, the power of the magnetron for the Bk ink is selected so that it will be like this.

The term "fixing" as used herein does not mean that all volatile components in the ink are volatilized out of the recording medium, but spreads from the area where the ink is adhered during recording to a wider area on the surface of the recording medium 106. It means that there is no such thing. Therefore, if at least the outline of the attached ink is dry,
It does not matter if the inside of the contour is not dry.

By irradiating the recording area of the Bk ink with a microwave immediately after recording, the recording medium 1 of the Bk ink 1
The fixing action at 06 is improved. As a result, the recording medium 1
The fixing of the ink on 06 was efficiently accelerated, the spread from the desired area to be printed was minimized, and high-quality printing without feathering became possible. Further, since the permeation of the recorded ink into the recording medium 106 is reduced, the amount of the dye or pigment, which is the coloring component of the ink remaining on the surface of the recording medium, is increased, and the recording density can be increased. Further, the irradiation of microwaves made it possible to adhere a larger amount of ink than before, and the recording quality could be improved by increasing the recording density.

Further, when another ink is recorded later on the area fixed by irradiating the microwave, it is possible to prevent the deterioration of the recording due to the mixing of the ink with the other ink to be recorded later. It was

Here, the ink bleeding of Bk and each of C, M, and Y is improved. By the way, each C, M, Y ink uses an ink having a characteristic of fixing in about 10 msec without the addition of a fixing means, and there is no ink bleeding between each C, M, Y. That is, when recording different inks in at least the same recording area in the recording of multicolor inks, it is possible to eliminate the bleeding with the inks recorded later by fixing the ink recorded before by the irradiation of microwaves. It has become possible.

Further, when the recording medium 106 is plain paper, it has a characteristic that after the recording, it becomes wrinkled due to the permeation of the ink, and when this is gradually dried, the wrinkle does not return. The fixing by microwave irradiation eliminates the wrinkles, and the recording medium 1
It became possible to improve the physical quality of 06.

Here, the propeller 114 also serves to diffusely reflect microwaves, but also has a role of moving volatile components in the evaporated ink from the vicinity of the recording head 102 to other places. In general, microwaves tend to generate standing waves in the waveguide 111 having a specific shape,
Although the ink on the recording medium 106 is easy to fix and hard to fix, the propeller 114 is provided.
Further, by scanning the recording medium 106 with the magnetron 103, the fixing of the recording medium 106 is made uniform.

FIG. 3 shows the ejection port 102 of the recording head 102.
It is a front view which shows arrangement | positioning of a. The recording head corresponding to each color has an ejection port 1 for ejecting Bk, C, M, and Y inks.
It has 128 02a each.

The arrangement distance between the colors is 1 inch between Bk and C, 1/2 inch between C and M, and 1/2 inch between M and Y. Also,
The interval between the 128 discharge ports 102a for each color is about 7
It is 0 μm. Each of these ejection ports 102a is provided with an ink liquid passage communicating with the ejection port 102a, and a common liquid for supplying ink to these liquid passages is provided behind the portion where the ink liquid passages are arranged. A room is provided. Outlet 1
The ink liquid paths corresponding to the respective 02a are provided with electrothermal converters that generate thermal energy used to eject ink droplets from these ejection ports 102a and electrode wirings that supply power to the electrothermal converters. ing. These electrothermal converters and electrode wirings are formed on a substrate made of silicon or the like by a film forming technique.

Further, by depositing a partition wall made of a resin or a glass material, a top plate and the like on this substrate, the discharge port 1 can be obtained.
02a, the ink liquid path, and the common liquid chamber. Each Y, M, and C ejection port 102 provided in the recording head 102
About 40 ng of ink is ejected from a, and about 80 ng of ink is ejected from the ejection port for Bk.

The components of each ink having the above characteristics are as follows.

1) Y C. I. Direct Yellow 86 3 parts Diethylene glycol 10 parts Isopropyl alcohol 2 parts Urea 5 parts Acetylenol EH (Kawaken Chemical) 1 part Water balance 2) MC I. Acid Red 289 3 parts Diethylene glycol 10 parts Isopropyl alcohol 2 parts Urea 5 parts Acetylenol EH (Kawaken Chemical) 1 part Water balance 3) C.C. I. Direct Blue 199 3 parts Diethylene glycol 10 parts Isopropyl alcohol 2 parts Urea 5 parts Acetylenol EH (Kawaken Chemical) 1 part Water balance 4) Bk C.I. I. Direct Black 154 3 parts Diethylene glycol 10 parts Isopropyl alcohol 2 parts Urea 5 parts Acetylenol EH (Kawaken Chemical) 1 part Water balance As mentioned above, each C, M, Y ink is a surfactant for Bk ink. Permeability is improved by adding acetylenol EH (Kawaken Chemical).
Other than acetylenol EH, other surfactants and alcohols are effective as adducts.

Here, as the recording head 102, an example in which an electrothermal conversion element is used for ink ejection has been shown, but the invention is not limited to this. For example, a piezoelectric element which is an electrothermal conversion element is used. It may be one. Further, other means may be used, and it is applicable to all ink ejecting means capable of achieving ink jet recording.

The microwave irradiation may be performed not only immediately after recording during the recording operation, but also at a timing that is not immediately after recording, for example, when the carriage 101 returns or immediately before recording during reciprocal recording. . This has a role of drying the water in the recording medium 106, and improves the recording quality.

Further, in the present embodiment, the platen 10
Although 8 is a metal plate having a flat shape, a metal plate having a large number of holes having a diameter of about 1 mm may be used. Since the recording area of the recording head 102 can be kept flat and the air permeability can be improved, there is an advantage that the volatile component in the ink easily diffuses from the rear surface of the recording medium 106.

(Embodiment 2) In Embodiment 1, 1
Although an example using five magnetrons has been shown, the present invention is not limited to this, and FIG. 4 shows an example using five magnetrons as a second embodiment. Here, magnetrons 131 to 135 are arranged at both ends of each of the Bk, Y, M, and C recording heads. When the carriage 101 moves in the direction A in the figure, first, Bk
Record ink and fix with Magnetron: 132,
Next, C ink is recorded and fixed by magnetron: 133, then M ink is recorded and magnetron:
Fix at 134, then record Y ink and fix at Magnetron: 135.

When the carriage 101 moves in the direction opposite to the direction A in the figure, first, Y ink is recorded and fixed by magnetron: 134, then M ink is recorded and magnetron: 133. Fixing, then C ink recording, magnetron: 132 fixing, then Bk ink recording, magnetron: 1
Fix at 31.

As described above, since recording can be performed in both directions with respect to the main scanning direction, the recording speed is doubled as compared with unidirectional recording. Further, the fixing characteristic of each C, M, Y ink is Bk.
An ink having the same characteristics as the ink may be used, that is, an ink to which a surfactant, alcohol or the like is not added may be used. this is,
This is effective for improving the color development characteristics of each C, M, Y ink. When a surfactant, alcohol, or the like is added to each of the C, M, and Y inks, the fixability is good, but there is a disadvantage that the coloring property is not good, and this point can be improved.

Although an example having a plurality of magnetrons is shown here, it is possible to use one magnetron and to irradiate a plurality of regions with microwave irradiation by the structure of the waveguide. Absent.

(Third Embodiment) Multi-pass In the first embodiment, an example in which the entire printing area is printed by one main scan is shown, but the present invention is not limited to this, and FIG. FIG. 11 is an explanatory diagram showing a process of recording in a recording area of a recording medium 106 as a third embodiment.
(A) shows a case of printing the entire print area by one main scan of the print head 102, and shows the case of the first embodiment.
(B) is a case where all of the print area is printed by two main scans, and half of the print area is printed by the first main scan.
In the next main scan, the print head is moved by ½ of the print head width in the sub-scanning direction orthogonal to the main scan direction, and the remainder of the first main scan and the next ½ of the print head width are set. Record. Record one after the other as well as your subordinates. The numbers in the figure indicate the number of main scans for printing.

In the case of recording as shown in (b), the amount of ink ejected in one main scan is half that in the case of (a). Therefore, the power of the magnetron for fixing is also 1
/ 2 is enough. This is an advantage that the power supply unit of the recording apparatus can be downsized. Here, the case where one printing area is printed by two main scans has been shown, but the present invention is not limited to this, and the same printing area is printed twice, four times, or five and six times. There is an advantage that the fixing power can be set to 1 / N when recording is performed by N (integer of 2 or more) multi-passes in the scanning direction.

(Fourth Embodiment) Corresponding to Recording Medium In the first embodiment, the recording medium 106 is particularly plain paper, but there are various recording media 106, for example, a transparency (transparent) sheet. Then, there are many things that are harder to fix than plain paper. This can be dealt with by changing the power of the magnetron or changing the main scanning speed to change the microwave irradiation time depending on the recording medium.

For example, the power is increased for a transparency sheet having a long fixing time. Alternatively, the main scanning speed is reduced with the same power to increase the microwave irradiation time. In this way, by providing the optimum energy required for fixing depending on the recording medium 106, it is possible to obtain an efficient and highest recording speed without wasting energy.

(Fifth Embodiment) Vertically-Aligned Head In each of the above-described embodiments, the recording head 102 is a horizontally-arranged type recording head, but the present invention is not limited to this, and FIG. Shows a case of a recording head having vertical and ejection ports as a fifth embodiment. The ejection ports 102a of the recording head 102 are linearly arranged in a direction orthogonal to the main scanning direction. Further, each ink is also arranged linearly.

In the recording operation, first, the recording head 102 scans relatively with the recording medium 106 to record Bk ink. Next, the waveguide 111 communicating with the magnetron scans and fixes the Bk ink recording portion. Next, C ink is recorded, and then M and Y inks are sequentially recorded. The present invention is also applicable to the recording head 102 having such ejection ports 102a arranged vertically.

[0045]

As described above, according to the present invention,
In the ink jet recording apparatus, by irradiating the recording area of the ink with the microwave immediately after recording, the fixing action on the recording medium is improved. As a result, the fixing of the ink on the recording medium can be efficiently accelerated, the spread from the desired recording area can be minimized, and high-quality recording without a feathering phenomenon can be achieved. Further, since the permeation of the recorded ink into the recording medium is reduced, the recording density can be increased.

Further, it becomes possible to adhere a larger amount of ink than before by the irradiation of microwaves, and the recording quality can be improved by increasing the recording density. Furthermore, when multi-colored ink is used, the recording area of the ink of the first color is irradiated with microwaves to fix it, and then other ink is recorded. It is possible to prevent the deterioration of recording by mixing the ink of (1), and it is possible to improve the physical quality of the recording medium by eliminating wrinkles in the fixing by the irradiation of microwaves.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of an embodiment of a recording apparatus.

FIG. 2 is a diagram of a recording head mechanism of FIG.

FIG. 3 is a front view of a recording head

FIG. 4 is a diagram of a recording head mechanism according to a second embodiment.

FIG. 5 is an explanatory diagram of a recording process of Example 3.

FIG. 6 is a front view of a recording head according to a fifth embodiment.

[Explanation of symbols]

 101 Carriage 102 Recording Head 102a Ejection Portion 103, 131-135 Magnetron 104, 105 Guide Axis 106 Recording Medium 108 Platen 111 Waveguide

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI Technical indication location B41J 29/00 H (72) Inventor Hiroshi Taka 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Within the corporation

Claims (7)

[Claims] 1. An ink jet recording method in which a carriage equipped with a recording head for ejecting ink droplets records a recording area on a recording medium by main scanning and sub-scanning operations. Is provided, and the recording medium immediately after recording is irradiated with the microwave during the main scanning recording operation. 2. The recording ink comprises a plurality of types of ink, and the microwave is irradiated immediately after at least the first recording on the recording medium.
Inkjet recording method described. 3. The ink to be recorded is a plurality of types, and the ink for the first recording is more preferable than the ink for the subsequent recording.
The ink jet recording method according to claim 2, wherein the ink has a characteristic of having slow permeability to the recording medium. 4. The ink jet recording method according to claim 1, wherein the recording medium has a plurality of regions for irradiating the microwave. 5. The means for generating the microwave is a magnetron, which has a structure for irradiating the recording area with microwaves through a waveguide, and has a propeller inside the waveguide. Item 5. The inkjet recording method according to any one of Items 1 to 4. 6. The ink jet recording method according to claim 1, wherein the recording head that ejects the ink droplets is an electrothermal conversion element and / or an electromechanical conversion element. 7. An ink jet recording apparatus using the ink jet recording method according to any one of claims 1 to 5.