JP3820794B2 - Inkjet printhead. - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a roof shooter-type ink jet print head with good thermal energy efficiency when ejecting ink droplets with the pressure of thermonuclear bubbles.
[0002]
[Prior art]
In recent years, ink jet printers have been widely used. The ink jet printer includes a pressure unit for pressurizing and discharging ink. The configuration of the pressurizing unit includes a thermal jet system that ejects ink droplets with a force generated by bubbles and a piezo system that ejects ink droplets by deformation of a piezoresistive element (piezoelectric element).
[0003]
The printing method with these configurations has a lower printing energy than the electrophotographic method using toner, which is a powdery printing material, due to the process of ejecting ink, which is a color material, as ink droplets directly toward the recording paper. It is easy to colorize by mixing ink, and the print dots can be made small, so the image quality is high, the amount of ink used for printing is low, and the cost performance is excellent. As a printing method widely used as
[0004]
The thermal jet system has two configurations depending on the ink droplet ejection direction. That is, there are a configuration in which ink is ejected in a direction parallel to the heat generating surface of the heat generating portion as the pressurizing portion, and a configuration in which ink is discharged in a direction perpendicular to the heat generating surface of the heat generating portion.
[0005]
8 (a), (b), and (c) are configured to discharge in a direction parallel to the heat generating surface of the heat generating portion. FIGS. 8 (d), (e), and (f) are the heat generating portions. FIG. 6 schematically shows a configuration for discharging in a direction perpendicular to the heat generation surface. As shown in FIG. 2A or FIG. 4D, a heat generating portion (heat generating element) 2 is formed on the silicon substrate 1, and an orifice plate 3 is formed facing the silicon substrate 1. An orifice 4 is formed on the side of the heat generating element 2 in FIG. 5A and opposite the heat generating element 2 in FIG. The heating element 2 is connected to an electrode (not shown), and the ink 5 is always supplied to the ink flow path in which the heating element 2 is provided.
[0006]
In order to eject ink droplets from the orifice 4, first, as shown in FIG. 5B or FIG. 5E, the heating element 2 is heated by energization according to the image information. (2) The membrane bubbles are combined to form a membrane bubble (6), and (3) the membrane bubble 6 is adiabatically expanded and grows, pushing the surrounding ink away from the orifice 4. The ink 5 'is pushed out, and the pushed out ink 5' is ejected from the orifice 4 toward the paper surface as ink droplets 7 as shown in FIG. Thereafter, (4) the grown film bubbles are shrunk by heat taken by the surrounding ink, and (5) the film bubbles finally disappear, and the next heating element is awaited to be heated. This series of steps (1) to (5) is performed instantaneously.
[0007]
A structure that ejects ink droplets in a direction perpendicular to the heat generating surface of the heat generating element is called a roof shooter type thermal ink jet head, and is known to consume very little power. As a method for manufacturing this roof shooter type thermal ink jet head, a silicon LSI formation technique and a thin film are formed on a large number of chip substrates (for example, 90 or more wafers having a diameter of 6 inches or more) partitioned on a silicon wafer. There is a method in which a plurality of heat generating elements, a drive circuit for individually driving these elements, and an orifice corresponding to the plurality of heating elements are collectively formed monolithically using a forming technique.
[0008]
FIG. 9 (a) is a side sectional view showing a schematic configuration of a roof shooter type thermal ink jet head (hereinafter simply referred to as an ink discharge head) produced as described above, and FIG. (a) AA 'cross-sectional arrow view, (c) is a reduced plan view with a part thereof removed.
[0009]
FIG. 10 is an enlarged perspective view showing the orifice plate separated upward in order to easily understand the internal structure of the conventional ink jet printer head.
As shown in FIGS. 9 (a), (b), (c) and FIG. 10, the ink discharge head 10 is a drive circuit 12 made of LSI formed on a chip substrate 11 (see FIG. 9 (a)). A thin-film heating resistor 13, an individual wiring electrode 14 connecting the heating resistor 13 and the drive circuit 12, a common electrode 15 serving as a common wiring for grounding, and partition walls 16 and 17 stacked thereon. (17a, 17b) and an orifice plate 18 laminated thereon. A discharge nozzle (orifice) 19 is formed on the orifice plate 18.
[0010]
Each of the heating resistors 13 is partitioned by a partition wall 17a that contacts the comb body of the comb-shaped partition wall 17 formed on the individual wiring electrode 14 side, and a partition wall 17b that contacts the comb tooth portion of the width w extending from the partition wall 17a. It arrange | positions in the made small bunches 21, and is isolated from the adjacent other heating resistor 13. An ink flow path 22 is formed on the opening side of the small tuft 21 parallel to the direction in which the heating resistors 13 are arranged, and an ink supply groove 23 is formed in communication with the ink flow path 22. In addition, an ink supply hole 24 communicating with the ink supply groove 23 and penetrating the lower surface of the substrate is formed.
[0011]
The heating resistor 13 in the small chamber 21 isolated as described above is connected to the ink supply hole 24, the ink supply groove 23 and the ink flow from the ink cartridge (not shown) connected to the ink supply hole 24 on the back surface of the substrate. Ink is supplied through the path 22. The heat generating resistor 13 is selectively driven by the drive circuit 12 via the individual wiring electrodes 14 to generate heat, generate film bubbles, and discharge the ink from the discharge nozzle 19 toward the paper surface (not shown) by the pressure. To do.
[0012]
By the way, as colorization of printers progresses as in recent years, in response to this, printers are required to have a high resolution of 720 dpi or 800 dpi or more. In order to realize such a high printing dot density, it is necessary to make the juxtaposition density of the pressurizing portions (heating resistors 13) denser. For that purpose, the width w of the partition wall 17b must be (smaller) narrowed to narrow the space between the tubules 21, and the parallel density of the resistance heating portions 13 must be increased. That is, the aspect ratio t / w between the width w and the height t of the partition wall 17b must be increased.
[0013]
However, if the aspect ratio t / w is set to “t / w = 1.0” or more, the partition wall 17b becomes insufficient in strength in the photolithography development process during the manufacturing process, and is desired to be crushed or collapsed. The partition wall of the shape is not formed, which causes an obstacle to the flow of ink into the tubule 21. That is, it is difficult to form the partition wall 17b so that the aspect ratio t / w becomes “t / w = 1.0” or more from the viewpoint of the strength of the photosensitive resin that is the material of the partition wall.
[0014]
Therefore, in order to increase the arrangement density of the heating resistors 13 and reduce the aspect ratio t / w of the partition wall 17b to less than 1.0, the partition wall 17b can maintain the width w of the partition wall 17b without changing the width. It was thought that there was no method corresponding to high resolution other than the method of making the arrangement density of the heating resistors 13 denser by narrowing the partitioning chamber 21.
[0015]
[Problems to be solved by the invention]
However, if the size of the tubule 21 partitioned by the partition wall 17b is reduced in order to increase the arrangement density of the heating resistors 13 as described above, the size of the heating resistor 13 arranged in the tubule 21 is also reduced. . As a result, there arises a new problem that it becomes difficult to ensure the area of the heating resistor 13 necessary for properly ejecting ink droplets.
[0016]
On the other hand, as shown in FIG. 9 (c), the small tuft 21 has no partition wall on the ink flow path 22 side, and one side of the ink flow path 22 side of the four sides is open to the entire surface. When thermonuclear bubbles are generated due to heating of the resistor 13, the ink discharge ink flow path 22 from the entire open surface in the horizontal direction in which the pressure of the ink discharge bubbles is different from the vertical ink discharge direction from the initial heating stage. Will be partly dispersed so as to flow backward. For this reason, there has been a problem that the energy efficiency of ejecting ink is lowered. As a measure for solving this problem, it has been proposed to provide a partition wall that prevents pressure dissipation at the ink inlet, but such a partition wall is similar to the above-described partition wall or is provided independently. Therefore, it has a problem that it is more likely to collapse in the manufacturing process than the partition.
[0017]
An object of the present invention is to provide a roof shooter-type ink jet print that can eject ink droplets with high energy efficiency and can stand up partition walls and the like accurately and easily with high aspect ratio, which is advantageous for high printing density. Is to provide a head.
[0018]
[Means for Solving the Problems]
The configuration of the ink jet print head of the present invention will be described below.
An inkjet print head according to the present invention includes a plurality of heating elements that generate thermal energy for discharging ink disposed at predetermined positions on a substrate, and a vertical cross section that is rectangular. A partition wall that continuously surrounds the entire circumference in the horizontal direction and has an opening at least at one place, and forms a pressurizing chamber for generating air bubbles by each heating element and applying pressure to the ink, and the partition wall An orifice plate provided opposite to the substrate through which an ink discharge nozzle is formed at a position corresponding to the heating element, and the pressurizing chamber communicate with each other through the opening and should be supplied to the pressurizing chamber A common flow path for feeding ink, the partition wall surrounding the heat generating element in a rectangular shape, and the opening extending over three sides excluding one side of the partition opposite to the common flow path. , So that the edge surface is flat and the same surface in the horizontal direction It is provided.
[0019]
The opening is formed, for example, by removing an end portion of the partition wall on the orifice plate side as described in claim 2, and, for example, the end portion of the partition wall on the substrate side, as described in claim 3. It is formed by removing. When the substrate side end is removed, the part of the partition where the opening is provided is installed on the orifice plate, for example, according to claim 4.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
FIGS. 1A, 1B, and 1C are views showing the manufacturing method of the thermal ink-jet head in the first embodiment in the order of steps, each formed on a silicon chip substrate in a series of steps. A schematic plan view and a cross-sectional view of the state are schematically shown. In these drawings, for convenience of explanation, only one print head of the thermal ink jet head for full color (same as the configuration of the monochrome ink jet head) is shown, but actually, as will be described later. A print head having a plurality of (usually four) print heads is formed on a single substrate (silicon chip). FIG. 6 (c) shows 36 ink discharge nozzles (orifices) 44, but actually 128 or 256 are formed in a line.
[0022]
2 (a), (b), and (c) are enlarged top plan views of FIGS. 1 (a), (b), and (c), respectively. The middle row of (b) and (c) is an AA 'cross-sectional arrow view (see Fig. (a)), and the lower row is an BB' cross-sectional view (see Fig. (a)) of the upper row. is there. In addition, the cross-sectional view shown in the middle of FIGS. 1 (a), (b), and (c) is the same as the cross-sectional view shown in FIGS. 1 (a), (b), and (c), respectively. In FIGS. 2A, 2B, and 2C, for convenience of illustration, 128 or 256 orifices are represented by 5 orifices.
[0023]
In the manufacturing method of this thermal ink jet head, first, as a step 1, a driver circuit and its terminals are formed on a silicon substrate of 4 inches or more by an LSI formation process, and an oxide film having a thickness of 1 to 2 μm is formed. In step 2, using a thin film formation technique, a resistance film made of Ta (tantalum) -Si (silicon) -O (oxygen) and an electrode film made of Ti / W are formed, and wiring is formed on the electrode film by photolithography. A partial pattern is formed, and a fine heating resistor (pressurizing portion) pattern is formed on the resistance film. In this step, the position of the heating resistor is determined.
[0024]
FIG. 1A and FIG. 2A show a state immediately after the above steps 1 and 2 are completed. That is, on the chip substrate 31, a common electrode 32, a common electrode power supply terminal 33 (see FIG. 1A), an individual wiring electrode 34, a number of heating resistors 35, a drive circuit 36, and a drive circuit terminal 37 (see FIG. 1). a) see) is formed.
[0025]
Subsequently, as step 3, a partition wall member made of an organic material such as photosensitive polyimide is formed to have a height of about 20 μm by coating so as to form an ink reservoir (tuft) corresponding to each heating element 35. After patterning by etching in two steps using a single mask, curing (dry curing, baking) applying heat at 300 ° C. to 400 ° C. for 30 minutes to 60 minutes is performed, and the above photosensitive polyimide having a height of 10 μm A partition wall for sealing and a partition wall having a lower height are formed and fixed on the chip substrate. This patterning can also be performed by laser processing.
[0026]
Further, as step 4, a groove-like ink supply path is formed on the surface of the chip substrate by wet etching or sand blasting, and an ink supply hole which is open to the lower surface in communication with the ink supply path is formed.
[0027]
FIG. 1B and FIG. 2B show a state immediately after the above-described step 3 and step 4 are finished. That is, a groove-shaped ink supply path 38 and an ink supply hole 39 are formed, and the ink is formed in the portion where the common electrode 32 portion located on the left side of the ink supply passage 38 and the right individual wiring electrode 34 are disposed. The partition wall 40-2 for partitioning each heat generating resistor 35 and the heat generating resistor 35 in a shape lower by 1/3 than the above is formed. A flow path side partition wall 40-1 separated from the flow path is continuously provided.
[0028]
FIG. 3 is an enlarged perspective view for easy understanding of the state immediately after the process 3 and the process 4 shown in FIGS. 1 (b) and 2 (b) are completed. As shown in FIG. 2 (b) and FIG. 3, the partition walls 40-2 extending and stacked between the heating resistors 35 are comb-shaped if the flow path side partition 40-1 is a comb body. The tip of the comb tooth is in contact with and integrated with the seal partition 40.
[0029]
As a result, comb teeth are used as partition walls, and minute sections (small bunches) 41 in which the heating resistors 35 are located between the teeth are formed by the number of the heating resistors 35. The seal partition 40 also serves as one side of the partition that forms the tubule 41.
[0030]
Thereafter, as step 5, an orifice plate of a film made of polyimide having a thickness of 10 to 30 μm is coated with a thermoplastic polyimide as an adhesive on one side thereof to an extremely thin thickness of, for example, 2 to 5 μm. The orifice plate is stuck to the uppermost layer and pressed while heating at 390 to 300 ° C. to fix the orifice plate. Subsequently, a metal film having a thickness of about 0.5 to 1 μm such as Ni, Cu or Al is formed.
[0031]
Further, as a step 6, the metal film on the orifice plate is patterned to form a mask for selectively etching the polyimide, and then the orifice plate is 40 μmφ according to the above metal film mask by dry etching such as ECR. A large number of nozzle holes (orifices) are formed at once by making holes of ~ 39 μmφ. The hole formation may be performed using an excimer laser or the like.
[0032]
FIG. 1C and FIG. 2C show a state immediately after the above-described step 5 and step 6 are finished. That is, the orifice plate 43 covers the entire area except the portions of the power supply terminals 33 and 37, and the tuft 41 formed by the seal partition 40, the partition partition 40-2, and the flow path side 40-1 also covers the top. Thus, a fine individual cell having a height corresponding to a thickness (height) of 10 μm of the seal partition 40 is formed, and the flow path side partition 40-1 and the partition partition 40-2 are formed from the top to the bottom of the partition orifice. The end portion on the side of the plate 43 is disposed in a removed shape, and the removed portion forms the opening of the small chamber 41.
[0033]
An ink flow path 42 having a height of 10 μm is formed to communicate the opening of the tubule 41 with the ink supply path 38. Further, an ink discharge nozzle (orifice) 44 is formed on the orifice plate 43 by dry etching at a portion corresponding to the heating resistor 35.
[0034]
As a result, a large number of monocolor heads 45 having 128 or 256 ink ejection nozzles 44 in one row are completed on the silicon wafer.
The dry etching mask uses a metal film such as Ni, Cu, or Al, so that the selectivity of the resin to the metal film is approximately 100. Therefore, it is sufficient to form a mask with a metal film of 1 μm or less for etching a 39-40 μm polyimide film.
[0035]
Up to this point, the wafer is processed. Finally, as step 7, the silicon wafer is cut using a dicing saw or the like, divided into individual chip substrate units, die-bonded to a mounting substrate, terminal-connected, and an inkjet head in a practical unit. Is completed.
[0036]
As described above, the mono-color head 45 including the one row of ink discharge nozzles 44 is a monochrome ink jet head. Normally, in full-color printing, the subtractive three primary colors yellow (Y) and magenta (M) are used. , Cyan (C), and black (Bk) dedicated to the black portion of characters and images are added to require a total of four colors of ink. Therefore, at least four nozzle rows are required. According to the manufacturing method described above, it is possible to form a full color head by continuously connecting four rows of monocolor heads 45 in a monolithic manner, and the positional relationship of each row can be accurately determined by today's semiconductor manufacturing technology. It is possible to arrange.
[0037]
As shown in FIG. 3 above, this inkjet print head has a tuft 41 having an opening above the three sides and surrounded by a continuous partition wall in the horizontal direction. When thermonuclear bubbles are generated by heating 35, the pressure of the bubbles for ink ejection is induced in the vertical direction and concentrated in the direction of the orifice 44. Therefore, the thermal energy generated by bubbles can be used for ink ejection without waste, and energy efficiency is improved.
[0038]
Moreover, since the flow path side partition 40-1 and the partition partition 40-2 which form the tuft 41 are low in height (the height of the partition is 2/3 from the top to the bottom), the aspect ratio t / w becomes small. As a result, there is no loss or collapse during firing and curing, and the yield is improved.
[0039]
Further, since the partition partition 40-2 is reinforced by being supported at both ends in the horizontal direction by the seal partition 40 and the flow channel partition 40-1, the aspect ratio t / w exceeds “1” to some extent. Also, there is no loss or collapse during firing and curing. That is, the width of the partition wall can be narrowed, and the interval between the tubules 41 can be reduced accordingly. As a result, it is possible to create a high-resolution print head by reducing the interval while maintaining the heat generation function of the heat generation resistor 35 at the same level as the current state.
[0040]
In addition, for example, the partition walls partially different in height, such as the above-described partition walls having different heights in the seal partition wall 40, the flow path side partition wall 10-1, and the partition partition wall 40-2, are etched in two stages using different masks. By doing so, it can be easily formed.
[0041]
FIGS. 4 (a) and 4 (b) are diagrams showing another example of the configuration of the tubule 41 having openings on three sides and surrounded by a partition wall that is continuous in the horizontal direction as described above. . FIG. 6A shows an example in which the flow path side partition 47-1 and the partition partition 47-2 are arranged in a shape in which the chip substrate 31 side of the partition from the top to the bottom is removed and the opening 46 is provided below. Is shown. In order to actually form the flow path side partition wall 47-1 and the partition wall partition 47-2 having this shape, the flow path side partition wall 47-1 and the partition wall partition 47-2 are formed on the back surface of the orifice plate 43 which is not shown in the drawing. The orifice plate 43 is aligned and laminated on the substrate.
[0042]
FIG. 2B shows an example in which the flow path side partition and the partition partition are arranged in a shape in which the middle of the partition from the top to the bottom is removed, and the opening 48 is provided at the center. As a result, in the production of the flow path side partition walls 49-1, 50-1 and the partition partition walls 49-2, 50-2 which are arranged separately in the vertical direction as shown in FIG. The partition wall 49-2 is disposed on the orifice plate side, and the lower flow path side partition wall 50-1 and the partition wall 50-2 are disposed on the substrate 31 side.
[0043]
5 (a), (b), and (c) are diagrams showing an example of the configuration of the tubule 41 that has an opening in the flow path side partition wall and is surrounded by a partition wall that is continuous in the horizontal direction as a whole. is there. As shown in (a), (b), and (c) of the figure, the partition walls 51-2 have a common shape and are arranged in a continuous shape from top to bottom. In FIG. 9A, the flow path side partition wall 51-1 is removed from the upper end portion to form the upper opening 52, and in FIG. 5B, the flow path side partition wall 51-1 ′ is removed from the lower end portion. An opening 53 is formed, and in FIG. 5C, the flow path side partition wall 51-1 ″ is removed from the intermediate portion to form an intermediate opening 54.
[0044]
This configuration is also surrounded by a continuous partition wall in the horizontal direction. Therefore, when a thermonuclear bubble is generated by heating the heating resistor 35, the pressure of the bubble for ink ejection is induced in the vertical direction to the direction of the orifice 44. Energy efficiency can be improved by concentrating and using the thermal energy generated by generating bubbles without waste.
[0045]
FIG. 6 (a) is a plan view showing only one tubule 41, FIG. 6 (b) is a side view of the shape that can be adopted by the above-mentioned flow path side partition and the partition wall, and FIG. The side view of the shape that can be taken, FIG. 4 (d) is a side view of the shape that is inappropriate for both the flow path side partition wall and the partition partition wall. Here, the position of the partition wall of the tubule 41 shown in FIG. 6 (a) is changed to the flow path side partition wall 40-1 (or 47-1, 49-1, 50-1, 51-1, 51-1 ', 51-). 1 ″) is a position A, and a partition wall 40-2 (or 47-2, 49-2, 50-2, 51-2) is a position B.
[0046]
FIGS. 7A, 7B, and 7C are diagrams showing combinations of partition wall shapes that can be taken by the position A of the flow path side partition wall portion and the position B of the partition partition wall portion by broken lines. This will be described below. An opening is required at the position A on the flow channel side of the tubule 41 shown in FIG. 6 (a). If there is no opening here, there is a risk of crosstalk in which the discharge state is affected between adjacent tubules.
[0047]
Therefore, the position k cannot take the shape k4 shown in FIG. 6 (c), but can take any of the shapes k1, k2, or k3 shown in FIG. 6 (b). FIGS. 7 (a), (b) and (c) show this.
[0048]
Further, since the position B may or may not have an opening, the shape k4 shown in FIG. 6 (c) can be adopted in addition to the shape k1, k2 or k3 shown in FIG. 6 (b). is there. Similarly to the above, FIGS. 7A, 7B, and 7C show this.
[0049]
The shape k5 shown in FIG. 6 (d) is such that the partition wall surrounding the small tubule 41 is not continuous in the horizontal direction at either position A or position B, that is, from the adjacent partition wall at either position A or position B. It becomes a separated shape. Since this shape stands alone on the substrate before the orifice plate is installed, even if the partition aspect ratio t / w is somewhat small, the partition is missing during the firing and curing process. It cannot be used because it will collapse. In FIG. 7 (a), (b), (c), the fact that the broken line is not connected to the shape k5 indicates this.
[0050]
As can be seen from the broken line combination diagram of FIG. 7, the shapes which can be taken by the flow path side partition and the partition partition are the positions A and B shown in FIG. 4 (a) when the positions A and B shown in FIG. When both of the shapes are k2 and the positions A and B shown in FIG. 4B are both the shapes k3, the positions A shown in FIGS. 5A, 5B, and 5C are the shapes k1, k2, or k3. The position B is not limited to the shape k4. A configuration in which different shapes among the shapes k1, k2, or k3 are combined at the position A and the position B may be used.
[0051]
The wall on the orifice side of the partition wall k2 or k3 can be formed integrally with the orifice plate.
[0052]
【The invention's effect】
As described above in detail, according to the present invention, the pressurizing chamber (small chamber) is formed by being surrounded by a partition wall having a part of an opening and continuous in the horizontal direction. ) Can be concentrated in the vertical direction where the nozzles are located while maintaining a smooth supply of ink to the nozzles. This allows energy to be used for ink ejection without waste, improving energy efficiency. To do.
[0053]
In addition, since the partition wall surrounding the pressurizing chamber does not have an isolated part in the horizontal direction and each part supports each other, the baking / curing process is performed even when the aspect ratio t / w exceeds “1”. Therefore, the gap between the pressurizing chambers can be made narrower and the pressurizing chambers can be made closer to each other. The print head can be manufactured accurately and easily.
[Brief description of the drawings]
FIGS. 1A, 1B, and 1C are a schematic plan view and a cross-sectional view schematically showing a method of manufacturing a thermal ink jet head in a first embodiment in order of steps.
[Fig. 2] (a), (b), and (c) are enlarged views of the top view of Fig. 1 (a), (b), and (c), and the middle row is an AA 'cross-sectional arrow of the upper row. The lower view is a view taken along the line B-B 'of the upper view.
FIG. 3 is an enlarged perspective view for easy understanding showing a state immediately after manufacturing steps 3 and 4 are completed.
FIGS. 4A and 4B are diagrams showing another example of a configuration of a tubule having openings on three sides and surrounded by a partition wall that is continuous in the horizontal direction.
5 (a), (b), and (c) are diagrams showing an example of a configuration of a tubule having an opening in a flow channel side partition wall and surrounded by a partition wall that is continuous in the horizontal direction as a whole. .
6A is a plan view showing only one tubule, FIG. 6B is a side view of a shape that can be taken by a flow path side partition and a partition wall, and FIG. 6C is a side view of a shape that can be further taken by a partition wall. (D) is a side view of a shape inappropriate for both the flow path side partition and the partition partition.
7 (a), (b), and (c) are combined connection diagrams showing combinations of shapes that can be taken by a flow path side partition and a partition partition.
FIGS. 8A, 8B, and 8C are diagrams showing a configuration in which ink is ejected in a direction parallel to the heat generation surface of the heat generating portion, and FIGS. It is a figure which shows the structure which discharges an ink in the direction perpendicular | vertical to a heat generating surface.
9A is a side sectional view showing a schematic configuration of a conventional roof shooter type thermal ink jet head, FIG. 9B is a sectional view taken along the line AA ′ in FIG. 9A, and FIG. It is a reduction | restoration top view which removes and shows.
FIG. 10 is an enlarged perspective view of the conventional roof shooter type thermal ink-jet head, with the orifice plate cut away so as to clearly show the internal structure to be devised by the present invention.
[Explanation of symbols]
1 Silicon substrate
2 Heating part (heating element)
3 Orifice plate
4 Orifice (ink ejection hole)
5, 5 'ink
6 Membrane bubbles
7 Ink drops
10 Ink ejection head
11 Chip substrate
12 Drive circuit
13 Resistance heating part
14 Individual wiring electrodes
15 Common electrode
16, 17 (17a, 17b) Bulkhead
18 Orifice plate
19 Discharge nozzle (orifice)
21 Kobo
22 Ink flow path
23 Ink supply groove
24 Ink supply hole
31 Chip substrate
32 Common electrode
33 Common electrode feed terminal
34 Individual wiring electrodes
35 Heating resistor
36 Drive circuit
37 Drive circuit terminal
38 (38a, 38b, 38c, 38d) Ink supply path
39 Ink feed hole
40 Seal bulkhead
40-1 Channel side bulkhead
40-2 Partition wall
41 sections (small tufts)
42 Ink flow path
43 Orifice plate
44 Ink discharge nozzle (orifice)
45 Monocolor print head
46 opening
47-1, 49-1, 50-1, 51-1, 51-1 ', 51-1 "Channel side partition
47-2, 49-2, 50-2, 51-2 Partition wall
A, B Bulkhead position
k1, k2, k3, k4, k5 Bulkhead shape

Claims (4)

A plurality of heating elements that generate thermal energy for ejecting ink disposed at predetermined positions on the substrate, and a longitudinal section of the heating element are rectangular, and the plurality of heating elements are individually spread all around the horizontal direction. A partition wall that continuously surrounds and has an opening in at least one place, and generates a bubble by each heating element to apply pressure to the ink, respectively, and a wall facing the substrate through the partition wall An orifice plate provided with an ink discharge nozzle provided at a position corresponding to the heat generating element, and a common flow path that communicates with each of the pressurizing chambers through the opening and supplies ink to be supplied to the pressurizing chambers The partition surrounds the heat generating element in a rectangular shape, and the opening extends over three sides excluding one side of the partition opposite to the common flow path, and the edge surface is flat and horizontal. et disposed such that the direction of the same surface And inkjet printhead, characterized in that are.   2. The ink jet print head according to claim 1, wherein the opening is formed by removing an end of the partition wall on the orifice plate side.   The ink jet print head according to claim 1, wherein the opening is formed by removing an end of the partition wall on the substrate side.   4. The ink jet print head according to claim 3, wherein a portion of the partition where the opening is provided is installed on the orifice plate.

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