JPH10138480A - Inkjet recording head - Google Patents

Abstract

(57) Abstract: A plurality of substrates (heater boards) 100 each having a plurality of ejection energy generating elements are arranged on a base plate 300, and these are covered with a top plate 200 to form an ink flow path. In the full-line type ink jet recording head, the adjacent heater boards 100
Means for improving the product placement position accuracy and the product yield and reliability. For this reason, the heater board 100 is processed so that the arrangement gap of each adjacent heater board 100 becomes larger than the nozzle length area, thereby making the heater board arrangement gap x smaller. I was able to do it.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording head for an ink jet recording apparatus for performing recording by discharging a liquid, and more particularly to an ink jet recording head having a plurality of element substrates arranged to be long. .

[0002]

2. Description of the Related Art In recent years, the ink jet recording system has been widely used because high speed recording with low noise is possible. Above all, an ink jet of a system (hereinafter, also referred to as a “bubble jet system”) in which a state change is caused in the ink by applying thermal energy to the ink, and the ink is ejected by utilizing a pressure due to a thermal expansion of a generated gas. The recording head has advantages such as good responsiveness to a print (recording) signal and easy increase in the density of ejection ports.

In recent years, the amount of data to be printed has been increasing. Particularly, when drawings and the like are also printed out, a higher speed printing is required due to the large amount of data. It has become to.

The above-described bubble jet type ink jet recording head, which is a so-called "full line type" ink jet recording head in which discharge ports and electrothermal transducers are arranged long over the entire width of a printing material. And an ink jet recording apparatus provided with this kind of ink jet recording head is greatly expected to improve the above-described printing speed.

As such a full-line type ink jet recording head, a method is conceivable in which all the electrothermal transducers are formed on a single substrate (hereinafter referred to as a "heater board"). In such a case, if even one of the electrothermal converters provided on the substrate has a defect, the substrate cannot be used, and the yield is extremely reduced. Therefore, conventionally, in these full-line type ink jet recording heads, a configuration is adopted in which the electrothermal transducer is divided into a plurality of heater boards.

That is, a plurality of heater boards having a relatively small number of electrothermal converters having 32 to 128 nozzles are arranged on a single support with high precision in accordance with the nozzle arrangement density. Thus, for example, even if a defect occurs in one of the electrothermal transducers, it is only necessary to replace the heater board in that part, and since the heater board itself is reduced in size, it becomes easier to manufacture, so that compared to the conventional one Yield is significantly improved. An example of the above-described configuration is, for example, a configuration described in JP-A-2-212162.

[0007]

However, by adopting the above configuration, the above advantages can be enjoyed, but new problems also arise. That is, in the above-described configuration, since a plurality of heater boards are arranged on the support, the arrangement accuracy greatly affects print quality.

In order to improve the alignment accuracy, it is necessary to eliminate interference with adjacent heater boards, and it is necessary to strictly control the processing accuracy (verticality) of the heater boards.
These have been factors that hinder improvement in product yield.

The present invention has been made in view of the above situation, and provides means for improving the yield of the processing accuracy of the heater board and providing a reliable full-line type ink jet recording head. With the goal.

[0010]

SUMMARY OF THE INVENTION Accordingly, in the present invention, it is an object of the present invention to achieve the above object by providing the following ink jet recording head: generating energy for discharging ink. Having a plurality of substrates having ejection energy generating elements to be formed, arranging these substrates on a support, and forming an ink flow path by joining a top plate covering all of these substrates on each of the arranged substrates. In the ink jet recording head, the width of the substrate on the side opposite to the ejection energy generating element is defined as W ≦ w−2 / l with respect to the width w of the direction of the ejection energy generating element of each substrate. w.0.0
1 (where l is the length dimension in the direction perpendicular to the width dimension w), and is less than the area formed by each straight line drawn from the both ends of the rear part of the nozzle forming part to the both ends of the width dimension W. An ink jet recording head having the following dimensional shape.

[0011]

According to the structure of the present invention as described above, in order to solve the above-mentioned problems, a portion where the arrangement accuracy of the heater board (element substrate) affects the print quality, that is, the nozzle flow path connects the top plate to the heater board. Only in the range formed by the contact, the arrangement gap between adjacent heater boards is minimized, so that each heater board that can ensure processing accuracy is formed.

Further, the area outside the nozzle formation range has a size and a shape that allows a sufficient space (gap) between adjacent portions so as not to interfere with an adjacent heater board. Also, the processing accuracy yield of each heater board is improved, the interference at the time of arrangement is reduced, and the assembly yield is also improved. Therefore, it is possible to provide an ink jet recording head having higher printing quality and higher reliability.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below in detail based on an embodiment.

[0014]

FIG. 1 shows a long ink jet recording head using a base plate having a base for arranging a substrate (hereinafter abbreviated as "heater board") having an ejection energy generating element to which the present invention is applied. FIG.

In FIG. 1, reference numeral 100 denotes a heater board on which an electrothermal transducer for generating thermal energy for discharging ink is formed. The heater board 100 is made of single-crystal silicon, polycrystalline silicon, glass, metal, or the like. Alternatively, the electrothermal transducer is formed of a material such as ceramics, and is formed on the heater board 100 by a thin film manufacturing technique or the like.

Reference numeral 300 denotes a base plate for supporting the heater board 100. The base plate 300
For example, it is made of a material such as glass, alumina, sapphire, silicon, and metal. 310 is the base plate 3
A pedestal, which is a support member for arranging a heater board, provided on the top of the base plate. The pedestal 310 is attached to each heater board 10.
0 are independently supported, and are provided integrally with the base plate 300 in this embodiment. Here, by precisely providing a portion of the pedestal 310 corresponding to each heater board 100, it can be used as a guide when the heater board 100 is arranged.

Reference numeral 313 denotes a suction opening provided on the pedestal 310 to ensure that the heater board 100 is disposed. Reference numeral 400 denotes a wiring board (PCB) which is electrically connected to the heater board 100 and transmits a drive signal from the apparatus main body, and is provided on the base plate 300 similarly to the heater board 100. The wiring board (PCB) 400 and the heater board 100 are electrically connected by wire bonding. The wiring board 400 is electrically connected to the apparatus main body via a flexible cable (not shown), and the flexible cable and the wiring board 400 are connected by the connector 103. In the figure, reference numeral 103 denotes a connector, and 401 denotes a bonding pad.

Reference numeral 200 denotes a top plate which forms a flow path by being joined to the heater board 100 disposed on the base plate 300. This top plate 200 forms a discharge port and a flow path for discharging ink. With a flow channel for
The flow channel and the electrothermal transducer are joined on the heater board 100 so as to correspond to each other.

As a material forming the top plate 200,
Any resin can be used as long as it can form grooves accurately, and more preferably, a resin having excellent mechanical strength, dimensional stability and ink resistance. As such a material, an epoxy resin, an acrylic resin, a diglycol, a dialkyl carbonate resin, an unsaturated polyester resin, a polyurethane resin, a polyimide resin, a melamine resin, a phenol resin, a urea resin, and the like are preferable. From the viewpoint of, resins such as polysulfone and polyether polysulfone are desirable.

In the recording head having the above configuration,
The arrangement accuracy of the heater boards 100 has a great influence on the print quality. An error in the arrangement accuracy in the nozzle arrangement direction occurs due to the cutting accuracy of the heater board 100, the positioning accuracy at the time of arrangement, and the like.

FIG. 2 shows the shape of the heater board 100. As shown in FIG. 2, the heater board 100 having a deviation d is not perpendicular to the side of the heater board 100 in the nozzle arrangement direction on the side of the adjacent heater board. When they are adjacent to each other, if they attempt to match the discharge heater side at a predetermined gap, they will interfere with each other on the opposite side, causing an alignment error.
In addition, as shown in FIG. 3, when the heater boards 100 are arranged obliquely in the arrangement positioning, interference occurs on the side opposite to the discharge heater row as described above, and the arrangement is performed. Loss of accuracy.

In order to eliminate each error caused by the mutual interference as described above, in the embodiment of the present invention, the heater board is formed to have a sufficient dimension except for the nozzle forming portion.

FIG. 4 is a view schematically showing the dimensions of the heater board 100 and the state when the heater board 100 is positioned obliquely. y is the protrusion amount (step) dimension, x is the gap, z is the displacement dimension of the heater board at the rear when inclined by the dimension y, and w and l are the arrangement directions of the discharge energy generating elements on the outer shape of the heater board 100, respectively. The width and the length in the direction perpendicular to the width. Here, when the gap is inclined by the dimension y with respect to the gap x, the displacement z of the rear heater board is z 後方 l / w · y. In order to prevent the adjacent heater boards 100 from interfering with each other at the rear, it is necessary to satisfy 2 · z = 2 · l / w · y <x, assuming that both are inclined.

The front step size y is determined by the precision of the apparatus.
Is desirably suppressed to 10 μm or less. Here, when the front step dimension y is 10 μm or less, if the rear width dimension is W, and if W ≦ w−2 · l / w · 0.01, contact with the adjacent heater board 100 can be avoided. Here, w is the width dimension of the heater board 100 in the arrangement direction on the energy generation element side, the length of one wave, and the length dimension in the direction perpendicular to the one wave.

In order to ensure normal ejection characteristics of the nozzle, the gap x needs to be small (about 2 to 12 μm) at least within the range of the nozzle length. Behind that, the gap x does not affect the ejection.

Therefore, in the present embodiment, the heater board 100 was machined to the dimensions and shapes as shown in FIGS. FIG. 6 is a view cut along a line connecting the width W behind the heater board and the rear of the nozzle area, and the nozzle area is cut at right angles to the direction in which the energy generating elements are arranged. When the heater boards 100 are arranged, the gap is minimized in the nozzle area.

FIG. 5 shows the above and other shapes, but the area shown by the two-dot chain line is the cut line shown in FIG. 6, and an example in which the area is cut more linearly than the diagonal cut shown in FIG. It is.

FIG. 7 is a flow chart showing a sequence of a manufacturing process of the ink jet recording head in this embodiment. In this embodiment, 11 heater boards 1
A manufacturing method of a long multi-head using one top plate 200 with a groove for 00 will be described.

First, a base plate 300 having a heater board supporting portion for supporting the heater board 100 and a projection for positioning a wiring board (PCB) 400 is formed by die-casting an aluminum substrate. The support portion has a concave portion 311 for injecting an adhesive and an opening 3 for suction used for temporarily fixing the heater board 100.
13 are provided (see FIGS. 8 and 9 described later).

The recording head manufacturing process sequence includes the following steps (a) to (k) as apparent from FIG. That is, (a) the arrangement of each component described later, (b)
Adhesion of required parts, (c) tip processing, (d) wiring board 400
Mounting, (e) mounting of the spring unit, (f) charging of the spring, (g) joining of the top plate 200, (h) release of the spring charging (f), (i) mounting of the ink supply unit,
It is performed in each process sequence of (j) cover attachment and (k) sealing.

Hereinafter, details regarding the above sequence will be additionally described. FIG. 8 is a schematic diagram showing a base plate 300 formed by die-casting, and FIG. 9 is an enlarged view of a pedestal portion in FIG. 8 and 9, reference numeral 310 denotes a heater board support, 311 denotes a recess provided in the heater board support 310, 312 denotes an adhesive injection groove communicating with the recess 311, 313 denotes a suction opening, and 314 denotes a suction opening.
The positioning protrusions 315 of the wiring board 400 are depressions connecting the adhesive injection groove 312 and the recess 311.

The shaded portion and the surface of the supporting portion of the base plate 300 shown in FIG. 8 are polished. Thereby, the flatness of the support portion is increased, and the probability of a step when the heater boards 100 are arranged can be reduced. Further, both end portions of the base plate 300 are positioning portions for the apparatus, and the assembling accuracy to the apparatus can be improved.

While making the base plate 300,
A plurality of heater boards 100, each of which is formed into an electrothermal transducer by a thin film forming technique, on a silicon substrate are prepared.

Next, a plurality of prepared heater boards 10
0 is positioned on the heater board support portion of the base plate 300 with high precision using a positioning tool or the like. Here, the positioned heater board 100 is sucked by the vacuum tool installed below the base plate 300 from the suction opening 313 in FIGS. Thus, each heater board 100
Are sequentially arranged on the base plate 300 (step (a) in FIG. 7).

Next, the adhesive is poured from the adhesive injection groove 312 of the base plate 300. The adhesive injected at this time enters the recesses 315 that connect the adhesive injection groove 312 and the respective recesses 311, and enters the recesses 311 from the recesses 315 by capillary action. As described above, the recess 315 is provided at a place where the adhesive injection groove 312 and each recess 311 communicate with each other.
The adhesive accumulates at 15 and the adhesive flows smoothly into each recess 311. After that, the adhesive is left to dry, and after completely fixing the heater board 100, the suction of the vacuum tool is stopped. Further, when it is desired to fix the heater board 100 strongly, an adhesive may be injected from the above-described suction opening 313 and fixed (step (b) in FIG. 7).

After the placement and fixing of the heater board 100 are completed, the base plate 300 and the heater board 100 are removed in order to eliminate a step at the end of the heater board 100 on the discharge port side.
Grinding. This is because a top plate 200, which will be described later, is abutted against and joined to the discharge port side end of the heater board 100, and if there is a step in this portion, crosstalk occurs (step in FIG. 7). (C)).

Next, a PCB (wiring board) 400 is bonded to the base plate 300 while being positioned by the positioning projections 314 described above. With this, PCB400
The electrode pads provided on the heater board 100 and the electrode pads provided on the heater board 100 have a predetermined positional relationship corresponding to each other. Then, the electrode pads provided on the PCB 400 and the electrode pads provided on the heater board 100 are wire-bonded, so that the heater board 100 is connected to the PCB.
400 is electrically connected. At this time, a continuity check of the wire bonding is also performed (step (d) in FIG. 7).

Next, the top plate 200 is connected to the base plate 300.
A press-contact unit that functions to adhere to the upper heater board 100 is mounted. The press-contact unit includes a leaf spring member (not shown) that presses the heater board 100 and a spring fixing member that fixedly supports the leaf spring member. The leaf spring member has a plurality of notches in the longitudinal direction. Is divided into a plurality of pressing portions. Each pressing portion has a through hole, and a jig is inserted into the through hole to regulate and release the urging force of each pressing portion.

This press contact unit is connected to the base plate 300
When fixing the press-fit unit to the PCB4
Then, it can be fixed to the base plate 300 by screws, heat caulking or the like (step (e) in FIG. 7).

In order to join the top plate 200 onto the heater board 100, the urging force of each pressing portion is regulated by a jig (step (f) in FIG. 7).

After securing a sufficient space on the heater board 100 in this way, the ink flow path and the ejection energy generating element are aligned so as to correspond to each other, and the top plate 200 is joined to the heater board 100. (FIG. 7 process (g)).

Then, the top plate 200 is fixed by releasing the urging force of the pressing portion. At this time, the urging force of the pressing portion is released (fixed by the pressing portion) in order from the center pressing portion toward both ends. By releasing the biasing force in this way, the warpage of the top plate 200 can be corrected, and the deflection escapes to the outside.
A good bonding state can be ensured throughout. After the urging force of the pressing portion is released, the jig is completely removed from the head main body (step (h) in FIG. 7).

Next, at positions where the ink supply pipes are joined to both ends of the top plate 200, the ink supply unit is fixed to the base plate 300 by heat welding or the like. The ink is supplied into the top plate 200 by the ink supply unit. The ink supply direction can be supplied from both directions,
Further, the supply may be performed so as to circulate from either one. Further, a filter for trapping air bubbles is provided in the connector portion of the ink supply unit (step (i) in FIG. 7).

Finally, a head cover (not shown) is attached so as to cover the base plate 300, and a sealing agent is applied to the top plate joining portion and the wire bonding portion through a window provided at a location corresponding to the pressing portion of the head cover. To complete the ink jet recording head of this embodiment (steps (j) and (k) in FIG. 7).

In this embodiment, the adhesive injection portion is provided as the groove 212 on the side of the base plate on which the heater board is disposed, but may be provided as a through hole penetrating the base plate 300 as shown in FIG.

In the ink jet recording apparatus described so far, the type and number of mounted ink jet recording heads have been described using only one single color ink. However, a plurality of inks having different print colors and densities are used. A plurality may be provided corresponding to the above. That is, it is natural that the inkjet recording head of the present invention is also used for a color inkjet recording apparatus in which a plurality of inkjet recording heads corresponding to a plurality of color inks are mounted. In addition, in the embodiments of the present invention described above, the ink is described as a liquid, but the ink may be solidified at room temperature or below.

FIG. 10 is a diagram showing an example of the configuration of an ink jet recording apparatus equipped with an embodiment of the ink jet recording head of the present invention.

As shown in FIG. 10, this ink jet recording apparatus has four line heads 2201a to 2201a.
1d, and these line type heads 2201a to 2201
1d are fixedly supported in parallel by a holder 2202 at predetermined intervals in the direction of the arrow X. On the lower surface of each of the heads 2201a to 2201d, 3456 discharge ports are provided downward at intervals of 16 discharge ports / mm in a row along the direction of arrow Y, thereby enabling recording of 218 mm width. Has become.

Each of these heads 2201a to 2201d
Is a method of ejecting a recording liquid using thermal energy, and ejection is controlled by a head driver 2220.

Each of the heads 2201a to 2201
A head unit is configured including the d and the holder 2202, and the head unit can be moved up and down by a head moving unit 2224.

Further, below the heads 2201a to 2201d, head caps 2203a to 2203d correspond to the heads 2201a to 2201d, respectively, and are arranged adjacent to each other. Each head cap 22
Each of 03a to 2203d has an ink absorbing member such as a sponge inside.

Each of the caps 2203a to 2203d
Is fixed by a holder (not shown), and a cap unit is configured including the holder and each of the caps 2203a to 2203d. The cap unit can be moved in the arrow X direction by cap moving means 2225.

The heads 2201a to 2201d are supplied with inks of cyan, magenta, yellow, and black from ink tanks 2204a to 2204d through ink supply tubes 2205a to 2205d, respectively, to enable color recording.

In addition, this ink supply utilizes the capillary phenomenon of the head discharge port, and the ink is supplied to each ink tank 2204a.
The liquid level of 2204d is set lower than the discharge port position by a certain distance.

This apparatus has a chargeable seamless belt 2206 for conveying a recording paper 2227 as a recording material.

The belt 2206 is driven by a driving roller 220
7, running by a belt drive motor 2208 which is routed to a predetermined path by the idle rollers 2209, 2209a and the tension roller 2210, is connected to the drive roller 2207, and is driven by a motor driver 2221. Is possible.

The belt 2206 is provided for each head 2
The vehicle travels in the direction of arrow X immediately below the discharge ports 201a to 2201d. Here, the downward movement is suppressed by the fixed support member 2226.

Reference numeral 2217 denotes a cleaning unit for removing paper dust and the like adhering to the surface of the belt 2206.

Reference numeral 2212 denotes a charger for charging the belt 2206. The charger 2212 is turned on / off by a charger driver 2222, and the recording paper 2227 is moved to the belt 2 by an electrostatic attraction force due to the charging.
Adsorb to 206.

Before and after the charger 2212, the recording paper 2 is conveyed in cooperation with the idle rollers 2209 and 2209a.
Pinch rollers 2211 and 2121a for pressing the 227 against the belt 2206 are arranged.

Reference numeral 2232 denotes a paper feed cassette. The recording paper 2227 in the cassette 2232 is fed by a paper feed roller 221 driven by a motor driver 2223.
6 is sent out one by one by the rotation of
The sheet is conveyed to a chevron guide 2213 in a direction indicated by an arrow X by a conveying roller 2214 and a pinch roller 2215 driven by the motor 3. The guide 2213 is provided on the recording paper 22.
It has a chevron space that allows 27 deflections.

Reference numeral 2218 denotes a paper discharge tray from which recording paper on which recording has been completed is discharged.

The head driver 2220, head moving means 2224, cap moving means 2225, motor drivers 2221, 223, and charger driver 222
2 are all controlled by the control circuit 2219.

[0064]

As described above, according to the present invention,
By processing the shape of the heater board so that the arrangement gap of the heater board of the ink jet recording head becomes wider than the nozzle length area, the arrangement gap of the heater board can be made smaller, and further, the yield of the arrangement can be reduced. It can also be improved.

As a result, the print quality and the yield can be improved, and a highly reliable ink jet recording head can be provided.

[Brief description of the drawings]

Fig. 1 Schematic diagram of a long head

FIG. 2 is an explanatory diagram of a heater board shape.

FIG. 3 is an explanatory diagram of a heater board arrangement state.

FIG. 4 is an explanatory view of a heater board arrangement state.

FIG. 5 shows an embodiment of the present invention.

FIG. 6 shows an embodiment of the present invention.

FIG. 7 is a flowchart of a recording head manufacturing process according to the embodiment.

FIG. 8 is a schematic diagram of a base plate.

FIG. 9 is an enlarged view of a pedestal portion in FIG. 8;

FIG. 10 is a diagram illustrating a configuration example of an ink jet recording apparatus equipped with an ink jet recording head according to an embodiment.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 heater board (element substrate) 103 connector 200 top plate 300 base plate 310 pedestal 311 concave portion 312 adhesive injection groove 313 suction opening 314 positioning protrusion 315 depression 400 wiring board (PCB) w element width in the direction of element arrangement W element opposite to element Width dimension l width dimension w and perpendicular dimension

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masahiko Kubota 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Takeshi Okazaki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inside (72) Inventor Yoshikazu Omata 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Kiyomi Aono 3-30-2, Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Yuki Tajima 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc.

Claims (1)

[Claims] 1. A semiconductor device comprising: a plurality of substrates having discharge energy generating elements for generating energy for discharging ink; arranging these substrates on a support; and arranging all of these substrates on each of the arranged substrates. An ink jet recording head in which an ink flow path is formed by joining a top plate that covers each of the substrates, wherein each of the substrates is on the opposite side of the discharge energy generating elements with respect to the width dimension w in the direction of arrangement of the discharge energy generating elements of these substrates The width W of W ≦ w−2 · l / w · 0.
01 (where l is the length dimension in the direction perpendicular to the width dimension w), and is less than the area formed by each straight line drawn from the both end portions of the rear part of the nozzle forming part to both end portions of the width dimension W. An ink jet recording head having the following dimensional shape.