JP2008055915A - Liquid-jet recording head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an excellent recording head for reciprocating printing, which is compact and can provide high-definition image of high quality. <P>SOLUTION: Discharge ports 1 of the recording head 300 are disposed at a predetermined pitch so as to form discharge port arrays 21 to 23 and 31 to 33 almost parallel to each other. The discharge port arrays form discharge port groups whose discharge ports correspond to each other in the scanning direction of the recording head. The second group 30 of discharge port arrays comprised of the discharge ports 31 to 33 is adjacent to the first group 20 of discharge port arrays comprised of the discharge port arrays 21 to 23. The two groups 20 and 30 include respective discharge port arrays 21 and 31 to jet the same kind of liquid to adjacent arrays. The discharge ports of the discharge port arrays forming the groups are comprised so as to be complemented by each other in the scanning direction. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a liquid discharge recording head that applies a plurality of different types of liquid such as a plurality of colors to a recording medium such as paper, and more particularly to a bidirectional printing apparatus that performs recording while scanning the recording head bidirectionally. The present invention relates to a liquid discharge recording head used in the above.

  In a printing apparatus, particularly an inkjet printing apparatus, an improvement in recording speed in color printing is an important theme. As a method for improving the recording speed, in addition to increasing the length of the recording head, improvement of the recording (driving) frequency of the recording head, bidirectional printing, and the like are common. Compared with unidirectional printing, bidirectional printing is a cost effective means for the total system because the required energy is distributed over time when obtaining the same throughput.

  However, the bidirectional printing method is based on the principle that, depending on the configuration of the recording apparatus, in particular, the recording head, the ink ejection order of each color differs between the forward direction and the sub-direction of the main scanning, resulting in band-like color unevenness. Had a problem. This problem is caused by the ink ejection order, and therefore, when dots of different colors overlap even a little, they appear as a color difference more or less.

  As a configuration of the liquid discharge recording head for solving the above-described problem, Japanese Patent Application Laid-Open No. 1-208143 discloses a configuration in which nozzles of each color are arranged in the sub-scanning direction.

  On the other hand, Japanese Patent Laid-Open No. 58-179653 discloses a configuration in which a forward pass nozzle and a return pass nozzle are prepared. In this publication, the used nozzle or the used head is switched between the forward pass and the return pass so that the order of placing the respective colors is the same, and the configuration of the print head portion is Y (yellow), M (magenta), C This is a combination of recording heads that eject inks of (cyan) and Bk (black).

  In Japanese Patent Laid-Open No. 58-215352, a plurality of recording heads are composed of a plurality of head groups that eject inks of different colors, and the plurality of recording head groups are alternately shifted in the conveyance direction of the recording medium. A configuration to be arranged is disclosed. The configuration of this publication is excellent in that a high-resolution image can be easily formed because the discharge port pitch of each recording head can be increased with respect to a desired image density.

  However, in the configuration disclosed in Japanese Patent Laid-Open No. 1-208143, the recording head becomes relatively long with respect to the recording area of one color, and the apparatus becomes large in the sub-scanning direction. There's a problem.

  On the other hand, in the configuration in which a plurality of recording heads are combined as disclosed in JP-A-58-179653 and JP-A-58-215352, the width of the head increases in the scanning direction. There is a problem that the apparatus becomes large in the scanning direction. Such an increase in the size of the recording head in the scanning direction leads to an increase in scanning time, which is not desirable from the viewpoint of high-speed recording.

  Further, in the configuration disclosed in Japanese Patent Application Laid-Open No. 58-215352, when the recording head unit is configured by combining the respective heads, a deviation occurs in the alignment of each head, resulting in manufacturing variations. There was a problem that it was easy. In particular, in the case of a print head unit that discharges four colors Y, M, C, and Bk, the print heads are arranged in the order of Y-Bk-MC-C-M-Bk-Y, and the adjacent print heads are nozzles. It is necessary to shift and fix by half of the pitch, and in order to assemble such a recording head unit, the mechanism for positioning the recording head may be complicated and large.

  The present invention solves various problems such as an increase in the size of the above-described recording apparatus and manufacturing variations with respect to a recording head that performs reciprocal printing, and can provide a compact and high-resolution image with high image quality. An object of the present invention is to provide an excellent liquid discharge recording head.

  In order to solve the above-described problem, the liquid discharge recording head of the present invention scans the recording medium bidirectionally, and the first liquid and the second liquid of a different type from the first liquid. In a liquid discharge recording head for recording by discharging from different discharge ports, a plurality of discharge ports are arranged at a predetermined pitch in a direction different from the scanning direction. A first discharge port array group provided in plural so as to coincide with the scanning direction, and a first discharge port array group adjacent to the first discharge port array group and having the same discharge port array as the first discharge port array group The first discharge port array group includes a first discharge port array that discharges the first liquid and a second discharge port that discharges the second liquid. An outlet row, and the second outlet row group includes a third discharge port for discharging the first liquid. And a fourth discharge port array for discharging the second liquid, wherein the first discharge port array group and the second discharge port array group are the first discharge port array. And the third ejection port array are adjacent to each other, and the ejection ports forming the first ejection port array and the ejection ports forming the third ejection port array complement each other in the scanning direction. As described above, the discharge ports are arranged so as to be shifted in the arrangement direction.

  According to the above-described liquid discharge recording head, it is possible to obtain a desired high-resolution color image simply by aligning the first and second discharge port array groups. Further, the first discharge port array group and the second discharge port array group each discharge the same first liquid so that the first discharge port array and the third discharge port array are adjacent to each other. Since the liquid supply paths to the first and third ejection port arrays can be shared, the widths of both the scanning direction and the sub-scanning direction of the recording head can be simultaneously reduced. Is possible.

  Although the details will be described later as a more preferable additional configuration, the following configuration can be given. Each of these additional configurations can provide a special effect independently, but the configuration obtained by combining a plurality of additional configurations that can be combined is synergistic with the object of the present invention. Therefore, the configuration is more excellent.

  A common liquid chamber for supplying the first liquid to both the first discharge port array and the third discharge port array may be provided.

  In addition, the discharge port array is not limited to the one that discharges only the first and second liquids, and the discharge port array for discharging a third liquid different from the first and second liquids Each of the first discharge port array group and the second discharge port array group may be provided. In particular, when using Y, M, and C color inks, the first liquid is more preferably yellow ink.

  Further, in order to achieve higher image quality in the above-described reciprocating printing, the discharge port arrays forming the first discharge port array group and the second discharge port array group respectively discharge. It is desirable that the liquid types are arranged so as to be symmetrical with respect to the first and third ejection port arrays.

  Further, for example, an ejection port array for ejecting Bk ink may be provided separately from the first and second ejection port array groups.

  The first discharge port row group and the second discharge port row group described above may be integrated by being provided in the same orifice plate shape. Further, the energy generation element array groups for discharging the liquid of the respective ejection port array groups may be provided on the same substrate. By using such an integrated recording head, it is not necessary to align the above-mentioned ejection port array groups, and a more accurate recording head can be easily provided.

  Note that silicon is preferable as the substrate having the energy generating element group, and when the through hole for supplying the liquid is formed by anisotropic etching, the plane orientation may be <100> or <110>. More desirable. Further, since the orifice plate is formed of a photosensitive epoxy resin, the above-described high-density discharge port array group can be formed with high accuracy and ease.

  In another aspect of the invention, the liquid discharge head scans the recording medium bidirectionally, and discharges the first liquid and the second liquid of a different type from the first liquid, respectively. In a liquid discharge recording head that performs recording by discharging from an outlet, an orifice plate including a plurality of discharge port arrays in which a plurality of discharge ports are arranged at a predetermined pitch in a direction different from the scanning direction, and a discharge from the orifice plate An energy conversion element for discharging liquid corresponding to the outlet, a liquid supply path for supplying liquid to the discharge port array of the orifice plate, and a drive circuit for driving the energy conversion element A discharge port array on the orifice plate, a first discharge port array for discharging the second liquid in the scanning direction, and discharging the first liquid. The second discharge port array, the third discharge port array for discharging the first liquid, and the fourth discharge port array for discharging the second liquid, and supplying the first liquid. The supply path for supplying liquid supplies both the second discharge port array and the third discharge port array. According to the above-described embodiment, it is not necessary to align the ejection port array groups, and a highly accurate head can be easily provided, and the liquid supply paths to the two ejection port arrays can be shared. Thus, the width of both the scanning direction and the sub-scanning direction of the recording head can be reduced simultaneously. In addition, it is possible to arrange the drive circuit in a region where no supply port is provided.

  In the present specification, the “recording medium” means not only paper used in a general printing apparatus but also a wide variety of materials such as cloth, plastic film, metal plate, etc. that can accept ink. .

  The “ink” means a liquid that can be used for forming an image, a pattern, a pattern, or the like or processing the print medium by being applied on the print medium.

  Furthermore, the “pixel region” means a minimum region that expresses a primary color or a secondary color by applying one or a plurality of inks, and includes not only pixels but also superpixels and subpixels. Further, the number of scans required to complete the pixel region is not limited to one, and may be multiple.

  Further, the “process color” means a color that is formed by mixing three or more inks including a secondary color on a print medium.

  As described above, according to the present invention, it is possible to obtain a desired high-resolution color image only by aligning the first and second ejection port array groups. In addition, the first discharge port array group and the second discharge port array group are disposed so that the discharge port arrays that discharge the same first liquid are adjacent to each other. Since the liquid supply path to the outlet row can be shared, the width of both the scanning direction and the sub-scanning direction of the recording head can be reduced at the same time, and high-speed printing with little color unevenness can be achieved in reciprocating printing. It can be done easily.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(First embodiment)
1A and 1B are explanatory views schematically showing the main part of a recording head according to a first embodiment of the present invention. FIG. 1A is a schematic view seen from above, and FIG. 1B is a view for explaining the arrangement of ejection openings. (C) is sectional drawing. As shown in FIG. 1C, the recording head 300 according to the present embodiment includes a substrate 7 including a heating element 5 as an energy conversion element, and an orifice plate 6 that forms the discharge port 1.

  In this embodiment, the substrate 7 is formed of a silicon single crystal having a plane orientation <100>, and on the sparse upper surface (connection surface with the orifice plate 6), as shown in FIG. A driving circuit 3 including a driving transistor for driving the heating resistor element, a contact pad 9 for connecting to a wiring board described later, a wiring 8 for connecting the driving circuit 3 and the contact pad 9 and the like use a semiconductor process. Is formed. Further, the substrate is provided with five through holes formed by anisotropic etching in a region excluding the drive circuit 3, the heating resistor element 5, the wiring 8 and the contact pad 9, and each of the discharge port arrays described later. Ink supply ports 2 and 2a for supplying liquid to 21 to 23 and 31 to 33 are formed. FIG. 1A schematically shows a state in which the substantially transparent orifice plate 6 is placed on the substrate 7, and the ink supply port described above is omitted.

  The orifice plate 6 provided on the substrate is formed of a photosensitive epoxy resin in this embodiment, and corresponds to the heating resistor element 5 described above, for example, by a process described in Japanese Patent Application Laid-Open No. 62-264957. Thus, the discharge port 1 and the liquid flow path 10 are formed. Here, after forming the silicon oxide film or the silicon nitride film on the silicon substrate as described in JP-A-9-11479, the above anisotropic etching is performed, and then the through-hole, the discharge port, and the liquid flow path are formed. And removing the silicon oxide film or the silicon nitride film at the ink supply port is desirable because an inexpensive and precise ink jet head can be produced.

  The recording head 300 having the substrate 7 and the orifice plate 6 uses the pressure of bubbles generated by film boiling due to thermal energy applied by the electrothermal transducer 5 to discharge a liquid such as ink from the ejection port 1. Recording is performed by discharging. As shown in FIG. 2A, the recording head 300 is fixed to the ink flow path forming member 12 that communicates with the ink supply port described above, and the contact pad is connected to the wiring board 13 to be provided on the wiring board. When the electrical connection unit 11 is connected to an electrical connection unit of a recording apparatus described later, a drive signal or the like can be received from the recording apparatus. FIG. 2B is a perspective view showing an example of a recording head cartridge 100 provided with the recording head 300 of the present invention. As shown in FIG. A tank holder 150 for holding an ink tank 200 (200Y, 200M, 200C) for supplying ink to the forming member is provided.

  Here, in the recording head of this embodiment, a plurality of discharge ports 1 are provided, and these are arranged at a predetermined pitch to form discharge port arrays 21 to 23 and 31 to 33 that are substantially parallel to each other. ing. Here, in FIG. 1A, the i-th discharge port of each of the discharge port arrays 21 to 23 coincides with the arrow direction shown in FIG. As described above, the ejection port arrays 21 to 23 of the present embodiment correspond to the ejection ports corresponding to the scanning direction when the recording head is mounted on a later-described recording device or the like and is scanned. The first discharge port array group 20 is formed. The ejection port arrays 31 to 33 are also arranged in the same manner as the ejection port arrays 21 to 23, and the second ejection port array group 30 is adjacent to the first ejection port group 20 by the ejection port arrays 31 to 33. Is formed.

  In the present embodiment, among the six discharge port arrays by these two discharge port array groups, cyan (C) is the most in the outermost discharge port arrays 23, 33, magenta (M) is the most in the discharge port arrays 22, 32. The discharge port arrays 21 and 31 adjacent to each other on the inner side discharge yellow (Y). Therefore, yellow ink is supplied to the ink supply port 2a (ink supply port provided in the center), magenta ink is supplied to the two ink supply ports 2 adjacent to the ink supply port 2a, and the two outermost inks are supplied. Cyan ink is supplied to the supply port 2 from the aforementioned ink tanks 200Y, 200M, and 200C, respectively. Thus, the central ink supply port 2a supplies liquid to the two ejection port arrays 21 and 31, and the ink supply port 2a and the liquid flow path 10a are provided in the two ejection port arrays 21 and 31, respectively. Functions as a common liquid chamber.

  In this way, two discharge port array groups are provided in adjacent columns, each having a discharge port array that discharges the same type of liquid, and the other discharge port arrays and their drive circuits are substantially symmetrical with respect to this central portion. By disposing, the through holes as the ink supply ports 2 and 2a, the drive circuit, the heating resistance element, and the like can be disposed at equal intervals with respect to the substrate without waste. In this embodiment, the size of one heating resistor 5 is 30 μm × 30 μm, the width of the ejection port, the drive circuit and the wiring (see a in FIG. 1A) is 1.2 mm, and the upper surface of the substrate of the ink supply port 2 The width (see b in FIG. 1C) is 0.2 mm, and the substrate size can be 1.2 × 6 + 0.2 × 5 = 8.2 mm. Thus, reducing the size of the substrate also has the advantage that the capacity of the memory for holding the transfer data of the recording head can be reduced in proportion to the substrate size.

  Furthermore, in the present embodiment, as is apparent from FIGS. 1A and 1B, the first discharge port array group 20 and the second discharge port array group 30 are respectively the discharge port groups. Are arranged so as to be shifted in the arrangement direction of the ejection ports so that the ejection ports of the ejection port arrays 21 to 23 and 31 to 33 complement each other in the scanning direction described above. As shown in FIG. 1B, in the present embodiment, the discharge port arrays forming the first discharge port array group and the second discharge port array group are all 128 discharge ports, t1 = t2 = It is formed by forming rows at a pitch of about 40 μm (1/600 inch). The arrangement of the ejection port array 21 and the ejection port array 31 is exactly the pitch of the ejection port array with respect to the sub-scanning direction of the recording head (in the present embodiment, the same as the arrangement direction of the ejection port array). (T3 = 1 / 2t1 = about 20 μm).

  An example of a recording method using this recording head will be described with reference to FIGS.

  In the present embodiment, recording is performed by ejecting approximately 8 pl of ink from each nozzle. In a recording apparatus (shown in FIG. 10) equipped with the recording head of this embodiment, two types of recording, that is, a high-speed mode and a high-resolution mode, can be performed as an example of a method for image formation.

  7 and 8 are explanatory diagrams for explaining the operation in the high-speed mode described above. In this high-speed mode, in order to save time for image processing and data transfer, 600 pixels per inch is used in each of the main scanning direction and the sub-scanning direction, and two droplets are ejected at different positions in one pixel. Is. FIG. 7 shows a case where cyan and yellow dots are recorded at the same position. The dot position 231 and the dot position 232 with respect to the pixel (p) 230 formed by the main scanning lines (raster) R11 and R12. Two dots are recorded as one pair. Here, the dot position (d1) 231 indicates the upper left diagonal position, and the dot position (d2) 232 indicates the lower right diagonal position. In the figure, the dots at the dot position d1 and the dot position d2 are not shown overlapping, but in reality, as shown in FIG. 9, some of the dots usually overlap (shaded area in FIG. 9). It is.

  In this embodiment, the pixel p is formed by 2 rasters (R (n-1) 1, R (n-1) 2), and the nozzle pitch l2 is about 40 μm (1/600 inch). Since the first ejection port array group 20 and the second ejection port array group 30 are shifted by a half pitch with respect to the sub-scanning direction, the raster interval l1 is about 20 μm (1/1200 inch). .

  Here, when printing a primary color, for example, a single magenta color, from the ejection port array 22 (hereinafter referred to as M1) and the ejection port array 32 (hereinafter referred to as M2) to the dot positions d1 and d2 of the pixel p in the scanning direction. Regardless of this, one drop of each droplet is ejected to form an image (in this case, since it is the same color, there will be no difference in color development depending on the firing order).

  On the other hand, in order to print a secondary color, for example, green as shown in FIG. 7, the ejection port array 23 (hereinafter referred to as C1), the ejection port array 21 (hereinafter referred to as Y1), and the ejection port array 31 ( Hereinafter, an image is formed by discharging one droplet from each of the columns Y2) and the discharge port array 33 (hereinafter C2).

  When recording in the forward direction, the liquid droplets pass through the predetermined pixels p of the recording medium in the order of C1 → Y1 → Y2 → C2, and the droplets are in the order shown in FIGS. 8 (a) to 8 (d). Lands on pixel p. Here, at the dot position d1 of the pixel p, since the droplets have landed in the order of C → Y, the cyan color that has landed first becomes dominant. On the other hand, at the dot position d2, since the liquid droplets have landed in the order of Y → C, yellow coloration that has landed first becomes dominant.

  When recording in the backward direction, the recording medium passes through the predetermined pixels p in the order of the ejection port array of C2-> Y2-> Y1-> C1, and therefore in the order shown in FIGS. 8 (e) to 8 (h). A droplet lands on the pixel p. Here, at the dot position d1 of the pixel p, since the liquid droplets have landed in the order of Y → C, yellow coloration that has landed first becomes dominant. On the other hand, at the dot position d2, since the droplets have landed in the order of C → Y, the color of cyan that has landed first becomes dominant.

  As described above, in the above-described high-speed mode, when viewed in the pixel p, a dot in which cyan coloring is dominant and a dot in which yellow coloring is dominant are always used in pairs regardless of the scanning direction. This pixel has an intermediate green color.

  In fact, as shown in FIG. 9, since d1 and d2 overlap in the region of one pixel in the high speed mode including this pixel p, the order of implantation (applying) for one pixel in the high speed mode is as follows: The forward path is a cyan dot from C1, a yellow dot from Y1, a yellow dot from Y2, and a cyan dot from C2. On the return path, the cyan dot from C2, the yellow dot from Y2, the yellow dot from Y1, It becomes cyan dot. As described above, since the order of placing is symmetrical, in other words, the order of ink deposition is the same, it is possible to uniformly develop the green color. Therefore, the occurrence of color unevenness due to reciprocal printing can be prevented.

  Next, the high resolution mode will be described. In this mode, one pixel is set to 600 pixels per inch in the scanning direction and 1200 pixels per inch in the sub-scanning direction. When printing a single color (C, M, or Y), one shot per pixel. Liquid droplets are discharged. In this case, the image area is masked, and printing is performed after dividing the pixel into a pixel to be recorded with a set of C1, M1, and Y1 and a pixel to be recorded with a set of C2, M2, and Y2. In this case, although the nozzle density of each ejection port array is 600 per inch, it is possible to form 1200 pixels per inch in the sub-scanning direction, and easily form a high-definition image. be able to. In this high resolution mode, for example, when printing green, pixels are recorded with C1 and Y1 (cyan is strongly developed because it adheres to the recording medium in the order of C and Y), and recording is performed with C2 and Y2. There are two types of pixels that are different in color, that is, the pixel that performs the image (the yellow color is strong because it adheres to the recording medium in the order of Y, C), and the two are evenly arranged by appropriate masking. Thus, it is possible to reduce the color unevenness to a level that is difficult to detect.

  The above-described recording method is one of the methods suitable for performing reciprocal printing using the liquid discharge head of the present invention, and the image forming method using the liquid discharge head of the present invention includes the above two methods. It is not limited only to the recording mode.

(Second Embodiment)
3 and 4 are views showing a recording head according to a second embodiment of the present invention and a recording head cartridge equipped with the recording head. In the present embodiment, portions having the same functions as those in the first embodiment are assigned the same reference numerals, and detailed descriptions thereof are omitted. 3A and 3B are explanatory views schematically showing the main part of the recording head, where FIG. 3A is a schematic view seen from above, FIG. 3B is an explanatory view for explaining the arrangement of ejection openings, and FIG. 3C is a cross-sectional view. It is. 4A is a perspective view showing the recording head shown in FIG. 3 fixed to the ink flow path forming member 12, and FIG. 4B shows the recording head cartridge 100 provided with the recording head 300 of the present invention. FIG. 4C is a perspective view showing an example, and FIG. 4C is an explanatory diagram for explaining an ink tank that is detachably mounted on the recording head cartridge.

  This embodiment is different from the first embodiment described above in that a silicon substrate having a <110> plane orientation is used. In this embodiment, when the ink supply ports 2 and 2a are formed by etching, the etching proceeds perpendicularly to the substrate, so that the cross-sectional shape changes in the thickness direction as shown in FIG. It is possible to easily obtain an ink supply port with less. Therefore, the substrate size of this embodiment is determined by the pattern on the substrate surface, and the recording head can be further miniaturized. In addition, when forming the ink supply port having the shape shown in FIG. 3C, it can be easily formed by performing etching with the above-described configuration, but it may be formed by other methods such as sandblasting or laser processing. . As described above, when the ink supply port having the shape shown in FIG. 3C is formed by another method, it is not necessary to use a silicon substrate whose surface orientation is <110> as the material of the substrate.

  In this embodiment, the ink flow path forming member 12 has an ejection port for ejecting black ink (Bk) in addition to the recording head 300 capable of ejecting each of the Y, M, and C inks. The recording head 400 including the rows 40 and 41 is fixed, and these are combined to form a recording head cartridge capable of ejecting four colors of ink. Since black is not generally used to form secondary colors, it need not be symmetrically arranged. Further, in order to improve the recording speed in monochrome recording, the number of nozzles is larger than that of other color heads. In this embodiment, the discharge port arrays 40 and 41 for Bk are arranged so that the respective discharge ports complement each other in the scanning direction, similarly to the discharge port arrays 21 and 31. Thus, recording can be performed in the sub-scanning direction at a density twice the nozzle arrangement density.

  In this embodiment, printing can be performed in the recording mode as shown in the first embodiment.

(Third embodiment)
FIG. 5 is a diagram showing a recording head according to a third embodiment of the present invention. In the present embodiment, parts having the same functions as those in the first and second embodiments described above are given the same reference numerals, and detailed descriptions thereof are omitted. 5A and 5B are explanatory views schematically showing the main part of the recording head, where FIG. 5A is a schematic view seen from above, FIG. 5B is an explanatory view for explaining the arrangement of ejection openings, and FIG. 5C is a sectional view. It is.

  In the present embodiment, unlike the first and second embodiments described above, there are three through holes provided in the substrate 7, and the ink supply ports 2 b for the two outer ejection port arrays are the end portions of the substrate 7. And the ink flow path forming member 12. With such an arrangement, the size of the substrate of the recording head 300 can be further reduced.

(Fourth embodiment)
FIG. 6 is a diagram showing a recording head according to a third embodiment of the present invention. In the present embodiment, parts having the same functions as those in the first and second embodiments described above are given the same reference numerals, and detailed descriptions thereof are omitted. 6A and 6B are explanatory views schematically showing the main part of the recording head, wherein FIG. 6A is a schematic view seen from above, and FIG. 6B is a cross-sectional view.

  In this embodiment, the discharge port arrays 24 and 34 for discharging Bk are provided in the first and second discharge port array groups, respectively.

  When performing reciprocal printing, in order to perform the recording method for reducing the color unevenness described in detail in the first embodiment, at least two kinds of liquids used in an overlapping manner are ejected. If the discharge port arrays to be included are included in the first and second discharge port groups, it is possible to achieve an effect with respect to the superposition of liquids of that type. However, in order to obtain an image with less color unevenness, it is more desirable that the arrangement of the ejection port arrays for ejecting the superposed liquids is a contrasting Haiti as in the above-described embodiments.

  In each of the embodiments described above, the cyan, magenta, and yellow inks that are most commonly used in the ink jet recording field have been described as examples of the type of liquid to be superimposed. However, these light color inks may be included. The types of liquids that can be superimposed, such as green, blue, and red, may be other color combinations.

  Further, in each of the above-described embodiments, a configuration in which the first ejection port array group and the second ejection port array group are provided in the same orifice plate, or droplets from the ejection ports of the first ejection port array group. And an energy conversion element for discharging droplets from the discharge ports of the second discharge port array group on the same substrate. On the other hand, even if the first ejection port array group and the second ejection port array group are separate recording heads, and these are assembled into a head unit, the positions of the two heads relative to each other The present invention is applicable because it only needs to be combined. However, the configuration as in the above-described embodiment is a more preferable configuration in that it is not necessary to align the ejection port array of the recording head itself.

(Other)
Finally, a liquid discharge recording apparatus capable of mounting the recording head or the recording head cartridge described in the above embodiments will be described with reference to FIG. FIG. 10 is an explanatory diagram showing an example of a recording apparatus in which the liquid discharge recording head of the present invention can be mounted.

  In FIG. 10, the head cartridge 100 is mounted on the carriage 102 in a replaceable manner. The head cartridge 100 includes a recording head unit 50 and an ink tank 200, and is provided with a connector for transmitting and receiving signals for driving the head unit (not shown).

  The head cartridge 100 is mounted on the carriage 102 so as to be replaceable. The carriage 102 is provided with an electrical connection portion for transmitting a drive signal or the like to each head cartridge 100 via the connector. .

  The carriage 102 is guided and supported so as to reciprocate along a guide shaft 103 that extends in the main scanning direction and is installed in the apparatus main body. The carriage 102 is driven by a main scanning motor 104 through driving mechanisms such as a motor pulley 105, a driven pulley 106, and a timing belt 107, and its position and movement are controlled. A home position sensor 130 is provided on the carriage. This makes it possible to know the position of the shielding plate 136 when the home position sensor 130 on the carriage 102 passes.

  A recording medium 108 such as a printing paper or a plastic thin plate is separately fed one by one from an auto sheet feeder (hereinafter ASF) 132 by rotating a pickup roller 131 via a gear from a paper feeding motor 135. Further, the conveyance roller 109 is rotated (sub-scanned) through a position (printing unit) facing the ejection port surface of the head cartridge 100 by the rotation of the conveyance roller 109. The conveyance roller 109 is performed via a gear by the rotation of the LF motor 134. At this time, the determination of whether or not the paper has been fed and the determination of the cueing position at the time of paper feeding are performed when the recording medium 108 passes through the paper end sensor 133. Further, the paper end sensor 133 is also used to finally determine the current recording position from the actual rear end where the rear end of the recording medium 108 is located.

  The recording medium 8 is supported by a platen (not shown) on the back surface so that a flat print surface is formed in the printing unit. In this case, the head cartridge 100 mounted on the carriage 102 is held so that the discharge port surfaces thereof protrude downward from the carriage 102 and are parallel to the recording medium 108 between the two pairs of transport rollers. Yes.

  The head cartridge 100 is mounted on the carriage such that the direction of the ejection port array is different from the carriage scanning direction described above, and recording is performed by ejecting liquid from these ejection port arrays. In each of the above-described embodiments, an electrothermal transducer that generates thermal energy is provided in order to eject ink using thermal energy. Of course, other methods such as ejecting ink using piezoelectric elements are used. There may be.

FIG. 2 is an explanatory diagram illustrating a main part of a recording head according to a first embodiment of the invention. FIG. 3 is an explanatory diagram for explaining an example of a recording head cartridge on which the recording head according to the first embodiment of the invention is mounted. It is explanatory drawing which shows the principal part of the recording head of the 2nd Embodiment of this invention. FIG. 6 is an explanatory diagram for explaining an example of a recording head cartridge on which a recording head according to a second embodiment of the invention is mounted. It is explanatory drawing which shows the principal part of the recording head of the 3rd Embodiment of this invention. It is explanatory drawing which shows the principal part of the recording head of the 4th Embodiment of this invention. It is explanatory drawing which shows an example of the position of the discharge nozzle and pixel structure of embodiment of this invention. FIG. 4 is a schematic diagram illustrating a state of image formation by reciprocal printing by the recording head according to the embodiment of the present invention. It is a figure which shows the expansion condition of the dot in the pixel shown in FIG. FIG. 3 is an explanatory diagram illustrating an example of a recording apparatus in which the liquid discharge recording head of the present invention can be mounted.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ejection port 2 Ink supply port 3 Drive circuit 4 Contact pad 5 Energy conversion element (heating resistance element)
6 Orifice plate 7 Substrate 8 Wiring 9 Contact pad 10 Liquid flow path 11 Electrical connection 12 Ink flow path forming member 13 Wiring board 20 First discharge port array group 21, 22, 23, 24 Discharge port array 30 Second Discharge port array group 31, 32, 33, 34 Discharge port array 40, 41 Discharge port array 50 Recording head unit 100 Recording head cartridge 150 Tank holder 200 Ink tank 230 Pixel (pixel)
231 and 232 dot positions

Claims (14)

In a liquid discharge recording head for performing recording by discharging a first liquid and a second liquid different from the first liquid from different discharge ports while scanning the recording medium bidirectionally,
A first discharge port array including a plurality of discharge port arrays in which a plurality of discharge ports are arranged at a predetermined pitch in a direction different from the scanning direction so that the corresponding discharge ports coincide with the scanning direction. Group,
A second ejection port array group adjacent to the first ejection port array group and having the same ejection port array as the first ejection port array group,
The first ejection port array group includes a first ejection port array that ejects the first liquid, and a second ejection port array that ejects the second liquid,
The second ejection port array group includes a third ejection port array that ejects the first liquid, and a fourth ejection port array that ejects the second liquid,
The first discharge port row group and the second discharge port row group form the first discharge port row while the first discharge port row and the third discharge port row are adjacent to each other. The liquid discharge head, wherein the discharge ports forming the third discharge port array and the discharge ports forming the third discharge port array are arranged so as to be shifted in the arrangement direction of the discharge ports so as to complement each other in the scanning direction. .   The liquid discharge recording head according to claim 1, further comprising a common liquid chamber for supplying the first liquid to both the first discharge port array and the third discharge port array. .   The ejection port array for ejecting a third liquid different from the first and second liquids is provided in each of the first ejection port array group and the second ejection port array group. The liquid discharge recording head according to 1 or 2.   4. The liquid discharge recording head according to claim 3, wherein the first liquid is yellow ink, and the second and third inks are cyan ink and magenta ink.   In the discharge port arrays forming the first discharge port array group and the second discharge port array group, the types of liquids discharged are symmetrical with respect to the first and third discharge port arrays, respectively. 5. The liquid discharge head according to claim 1, wherein the liquid discharge head is disposed in a position.   In addition to the first and second discharge port array groups, a fifth discharge port array for discharging a different type of liquid from the liquid discharged from the first and second discharge port arrays is provided. The liquid discharge recording head according to claim 1, wherein the liquid discharge recording head is provided.   The liquid recording / discharging head according to claim 6, wherein the liquid discharged from the fifth discharge port array is black ink.   8. The liquid discharge recording head according to claim 1, wherein the first discharge port row group and the second discharge port row group are provided on the same orifice plate.   A plurality of energy generating element row groups for discharging liquid from the first discharge port row group and a plurality of energy generating element row groups for discharging liquid from the second discharge port row group are the same. The liquid discharge recording head according to claim 1, wherein the liquid discharge recording head is provided on a substrate.   The liquid discharge recording head according to claim 9, wherein the substrate is a silicon substrate having a surface orientation of <100>.   The liquid discharge recording head according to claim 9, wherein the substrate is a silicon substrate having a surface orientation of <110>.   12. The liquid ejection according to claim 10, wherein the substrate has a plurality of through holes for supplying liquid to each of the ejection port arrays, and the through holes are formed by anisotropic etching. Recording head.   9. The liquid discharge recording head according to claim 8, wherein the orifice plate is made of a photosensitive epoxy resin. In a liquid discharge recording head for performing recording by discharging a first liquid and a second liquid different from the first liquid from different discharge ports while scanning the recording medium bidirectionally,
An orifice plate having a plurality of discharge port arrays in which a plurality of discharge ports are arranged at a predetermined pitch in a direction different from the scanning direction;
An energy conversion element for discharging liquid corresponding to the discharge port of the orifice plate is provided, and a liquid supply path for supplying liquid to the discharge port array of the orifice plate and the energy conversion element are driven. An element substrate comprising a drive circuit for
The ejection port array on the orifice plate ejects a first ejection port array that ejects the second liquid in the scanning direction, a second ejection port array that ejects the first liquid, and ejects the first liquid. Arranged in the order of the third discharge port array, the fourth discharge port array for discharging the second liquid,
The supply path for supplying the first liquid supplies the liquid to both the second discharge port array and the third discharge port array.

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