JP2003072064A - Ink jet recording head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink jet recording head which can reduce irregularities in the ink drop discharge performance among inks when printed on a recording medium, by eliminating an alignment work for setting positions among a plurality of heads, and adjusting an ink discharge performance among heads, and the like for color printing. SOLUTION: A frame member 5 having a plurality of through holes 5c is jointed on an insulating substrate 4. A plurality of diaphragms 1 formed of a piezoelectric ceramic are arranged in parallel at equal intervals to a recess bottom face formed by the through hole 5c and the insulating substrate 4. An ink channel 2 between diaphragms 1, is made and spaces formed by both ends of each of diaphragms 1 and the frame member 5 are made ink reservoirs 6 and 7. A wall 5a which is constituted of a channel member 10 having driving electrodes 3 formed to side faces of each of diaphragms 1 and a nozzle plate 11 jointed onto the channel member 10, and separates at least adjacent through holes 5c of the frame member 5 is set to have a Young's modulus of 50 GPa or larger and a width W of 0.05 mm or larger. A width L between the wall 5a and a diaphragm 1A adjacent to the wall 5a is made equal to a width M of the channel 2. The ink jet recording head is constituted in this manner.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the printing of characters and images.
Installed in an inkjet recording device used for
Related to a jet recording head. 2. Description of the Related Art In recent years, with the spread of multimedia,
Instead of the impact type recording device, the inkjet method
Non-impact recording device using
Has been developed and its use is
It is expanding in the garden field. [0003] Such a non-impact type recording apparatus is known.
However, there are many recording devices that use the inkjet method.
Easy gradation and colorization and low running cost
The future has been attracting attention. FIG. 4 shows recording using an ink jet system.
Shows the inkjet recording head used in the device
The ink jet recording head 50 (hereinafter simply referred to as
The nozzle is composed of a flow path member 40 and a nozzle plate 41.
The flow path member 40 is formed on the insulating substrate 34 by pressure.
Multiple partitions 31 made of electro-ceramics are juxtaposed by bonding
And the frame body 35 so as to surround each partition 31.
Airtightly bonded by adhesion, ink
In addition to the flow path 32, both ends of each partition 31 and the frame 35
And the ink reservoirs 36 and 37, respectively.
Then, the insulating substrate 34 forming the bottom of one ink reservoir 36 is
The ink supply hole 38 is pierced and the bottom of the other ink reservoir 37 is formed.
An ink collecting hole 39 is formed in the insulating substrate 34 forming a surface.
The upper half of the side wall of each partition 31 has a drive
The pole 33 was formed. Also, the top surface of each partition 31 of the flow path member 40 and
The flow path 32 and the ink reservoir 36,
The nozzle plate 41 is joined so as to close the nozzle 37.
The chirping plate 41 has a cover 42 made of metal and a cover made of resin.
The lid part 42 communicates with each flow path 32.
Ink guide hole 43 and the nozzle portion 44
Indicates that an ink ejection hole 45 communicating with each ink guide hole 43 is opened.
Had been uttered. Reference numeral 46 denotes a lead of the driving electrode 33.
Reference numeral 47 denotes a driver IC for the driving electrode 33. The ink jet recording head 5
In order to eject ink droplets from 0, the ink supply hole
38 to the ink reservoir 36, the flow path 32, and the ink reservoir 37
Supplying and collecting through the ink collecting hole 39
Then, the drive electrodes 33 provided on both sides of the partition wall 31 are energized.
To bend the partition 31 to pressurize the ink in the flow path 32
To discharge ink droplets from the ink discharge holes 45.
Was supposed to. That is, the drive provided on both sides of the partition 31
When a voltage is applied to the electrode 33, the pressure for forming the partition 31 is increased.
Electroceramics causes shear mode deformation, while
The wall 31 has a substantially U-shape because the top and bottom are constrained.
, The bending displacement of the partition wall 31 causes
The ink in the flow path 32 is pressurized, and
Was ejected as ink drops (International Publication Number
WO 00/29217). According to the ink jet recording head 50,
In this case, ink reservoirs 36 and 37 are provided at both ends of the flow path 32.
Compared with a closed channel at both ends
To shorten the ink droplet ejection interval
Is supplied from the ink supply hole 38 to collect the ink.
The ink is collected from the hole 39 and flows into the flow path 32.
Is generated, so that air bubbles and
Prevent stagnation of ink aggregates
As a result, the ejection speed of ink droplets
The clogging of the hole 45 does not occur, and the flow path
The substrate 34 on which the member 40 is formed is formed of an insulating material
Therefore, the capacitance of the flow path member 40 can be reduced.
Power consumption can be reduced.
There was such an effect. [0010] However, FIG.
In the head 50, all the flow paths 32 share a common ink reservoir 36,
37 are connected to each other.
To perform color printing,
It is necessary to mount a plurality of heads 50 on the recording device,
As a result, the recording device cannot be downsized.
There was a title. A plurality of heads 50 are mounted on a recording apparatus.
To align the mounting position between the heads 50
Requires work and adjustment of ink ejection performance between heads 50
And these tasks are complicated,
Size of ink drops between each ink when printing on
Variations in bullet position cause print quality to deteriorate
There was a problem. [0011] Accordingly, the present invention relates to the above-mentioned section.
In view of the problem, the ink jet recording head of the present invention is insulated.
A frame member having a plurality of through holes is joined to a substrate,
Concave bottom surface formed by the through hole of the frame member and the insulating substrate
A plurality of partitions made of piezoelectric ceramics
And a space between the above-mentioned partitions as an ink flow path.
The space formed by both ends of each partition and the frame member is inserted.
Driving electrodes are formed on the sides of each partition.
Joined to the formed flow path member and the top surface of the frame member and each partition
Nozzle plate provided with ink ejection holes communicating with each flow path
And at least adjacent through holes of the frame member
The wall that separates is made of a material with a Young's modulus of 50 GPa or more.
And the width of the wall is 0.05 mm or more, and
The width between the wall and the partition wall adjacent to the wall is equal to the width of the flow path.
The feature is that it becomes difficult. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described.
explain. FIG. 1 shows an ink jet recording head according to the present invention.
FIG. 2 is a partially cutaway perspective view showing the ink jet printer of the present invention.
Sectional view for explaining the driving principle of the jet recording head,
FIG. 3 is an enlarged sectional view of a portion E in FIG. The ink jet recording head 20 has a
The channel member 10 and the nozzle plate 11
Is a planar shape on an insulating substrate 4 having a rectangular planar shape.
Is a frame member 5 having three substantially hexagonal through holes 5c.
The through holes 5c of the frame member 5 and the insulating substrate 4 are bonded.
The bottom of the recess formed by
The partition walls 1 are arranged side by side at equal intervals, and the space between the respective partition walls 1 is inserted.
And the ends of each partition 1 and the above
The space formed by the frame member 5 is defined as an ink reservoir 6 and an ink reservoir.
7 and an insulating group forming the bottom of one ink reservoir 6
The plate 4 has ink for supplying ink into each flow path 2.
The supply hole 8 is connected to the insulating substrate 4 forming the bottom of the other ink reservoir 7.
Ink collection for collecting ink in each flow path 2
Each has a hole 9 and the upper half of the side wall of each partition 1 is shown in FIG.
As shown, a driving electrode 3 is formed. According to the flow path member 10, one of the frame members 5 is provided.
Recess formed by two through holes 5c and insulating substrate 4
The partition 1, the flow path 2, and the ink reservoirs 6, 7
The head element 18 is constituted, and the head 20 shown in FIG.
Each head element 1
8 are supplied with inks of different colors, respectively.
Color printing can be performed by one head 20
You. The partition 1 is made of lead zirconate titanate,
Lead lanthanum titanate zirconate, magnesium niobate
Piezoelectric ceramics based on lead or a mixture of these
While forming the trapezoidal shape.
Yes, and polarized in the direction of the arrow as shown in FIG.
The cross-sectional area of each flow path 2 is 0.008 to 0.05 mm
^Two The inside of the flow path 2 is made of silicon nitride or the like.
The protective electrode S is applied, and the driving electrode 3 is eroded by the ink.
It is prevented from receiving. Further, each of the flow paths 2 and
The top surface of the partition 1 and the frame portion so as to cover the ink reservoirs 6 and 7.
The nozzle plate 11 is bonded to the top surface of the material 5 by bonding.
An ink ejection hole 15 communicating with each flow path 2 is formed in the sizzle plate 11.
Have. The nozzle plate 11 is made of molybdenum or Ni-Fe.
Lid 12 made of a metal such as a base alloy, polyimide resin, etc.
And a lid portion 12 made of a resin.
An ink guide hole 13 communicating with the flow path 2;
The nozzle portion 14 communicates with each of the ink guide holes 13.
The ink discharge hole 15 is opened. FIG. 3 shows a head 20 according to the present invention.
Thus, at least the adjacent through-hole 5c of the frame member 5 is
The cutting wall 5a is made of a material whose Young's modulus is 50 GPa or more.
And the width W of the wall 5a is set to 0.05 mm or more.
And the wall 5a and the partition wall 1A adjacent to the wall 5a
Is equivalent to the width M of the flow paths 2A, 2B, 2C,.
It is. Reference numeral 16 denotes a lead wire of the driving electrode 3;
Is a driver IC mounted on the insulating substrate 4 outside the frame 5
And each drive through a lead 16 wired on the insulating substrate 4.
The working electrode 3 is energized. A recording medium (shown below) using the head 20
To print on the substrate, first, the ink supply
An ink supply passage (not shown) communicating with the supply hole 8 and an ink supply passage;
A container provided with an ink recovery passage (not shown) communicating with the receiving hole 9
(Not shown), and a water circulation system (not shown)
Ink supply holes for ink such as pigment ink and water-based dye ink
8 to the ink reservoir 6, the flow path 2, and the ink reservoir 7,
The ink is circulated to be collected from the ink collection hole 9. In this state, for example, as shown in FIG.
Next, the driving electrodes 3b and 3c and the driving electrodes 3h and 3i
The positive voltage is applied to the drive electrodes 3a, 3d, 3g, 3j, respectively.
When the voltage of the negative electrode is applied, the partition walls 1a and 1b
2b, and the partition walls 1d and 1e
In order to bend to the 2d side, the inside of the flow paths 2a and 2d is filled.
Pressurized ink, the ink droplets from the ink ejection holes 15
Can be discharged. Next, each of the driving electrodes 3a to 3
When the power to d, 3g to 3j is cut off,
The partition walls 1a, 1b, 1d, 1e have their original shape by elastic action.
And the pressure inside the flow paths 2a and 2d is reduced.
The introduction of ink from the supply hole 8 is started, and
Plus and minus to the drive electrodes 3a to 3d and 3g to 3j described above.
When a voltage is applied in the reverse direction, a voltage is applied as shown in FIG.
When the walls 1a, 1b are bent outwardly with respect to the flow path 2a,
In both cases, the partition walls 1d and 1e are bent outward with respect to the flow path 2d.
Due to the displacement, the pressure inside the flow paths 2a and 2d is further reduced, and
Ink will be filled. And each driving electrode 3
When the energization to a to 3d and 3g to 3j is cut off, the bending displacement
The partition walls 1a, 1b, 1d, 1e which have been
Return to the original shape and enter the next ink droplet ejection stage
These operations are sequentially repeated by each head element 18.
The ink droplets can be ejected continuously by returning
It has become so. According to the head 20, each flow path
2 has ink reservoirs 6 and 7 at both ends,
The pressure wave generated in the flow path 2 upon ejection of the droplet
Since there is no reflection in the longitudinal direction of 2, the next ink droplet
Both ends of the flow path 2 are closed without adversely affecting the discharge of
Shorten the interval between ink droplet ejections compared to the squeezed one
be able to. Further, ink is supplied from the ink supply hole 8.
Then, the ink is recovered from the ink recovery hole 9 and
Can generate a flow of ink,
Prevents air bubbles and agglomerates of ink from staying.
Stops, causing the ink droplet ejection speed to decrease,
15 to prevent clogging and
Droplets can be ejected. Further, the substrate 4 on which the flow path member 10 is formed is
Due to the insulating material, the capacitance of the flow path member 10 is reduced.
Power consumption can be reduced. On the insulating substrate 4 of the flow path member 10,
Three head elements separated by a wall 5a of the frame member 5
18, each head element 18 has a different color.
By supplying ink, one head 20
-Printing can be performed. Further, at least the wall 5a of the frame member 5 is
With a material having a modulus of at least 50 GPa
The width W of the wall 5a is 0.05 mm or more, and the wall 5a
And the width L between the partition wall 1A adjacent to the wall 5a and the flow path 2
A, 2B, 2C,... Are equivalent to the width M,
The same voltage is applied to the driving electrodes 3 provided in the partition walls 1A, 1B,.
Is applied, the ink is ejected from all the ink ejection holes 15.
The ink droplet ejection speed can be made almost the same.
Therefore, a clear and clear image can be printed. That is, at least the yan of the wall 5a of the frame member 5
The reason why the switching rate is set to 50 GPa or more is as shown in FIG.
The ink droplets from the ink ejection holes 15 communicating with the flow path 2A.
Of the partition wall 1A adjacent to the wall 5a.
Then, a pressure wave is generated between the partition wall 1A and the wall 5a.
The pressure wave propagates through the ink and most of it propagates to the wall 5a
However, the Young's modulus of the wall 5a is less than 50 GPa.
Then, the pressure wave is attenuated by the wall 5a, and the pressure wave is
The pressure wave to be emitted is on the opposite side of the wall 5a across the partition wall 1A.
It is smaller than the pressure wave reflected by a certain partition 1B.
As a result, there is a difference between pressure waves acting on both side surfaces of the partition wall 1A.
From the state in which the partition wall 1A is bent and displaced in a substantially “U” shape.
The time to return to the neutral non-displacement state is shorter than that of the partition wall 1B.
And is discharged from the ink discharge holes 15 communicating with the flow path 2A.
The discharge speed and the discharge amount of the ink droplets are farther away from the wall 5a.
A, which communicates with a flow path, for example, the flow path 2B or the flow path 2C.
The ejection speed and ejection of ink droplets ejected from the ink ejection holes 15
Ink discharge that is smaller than the discharge amount and communicates with each flow path 2
The ejection speed and amount of ink droplets ejected from the holes 15
Ragging occurs and the displacement of the landing position also increases.
This is because that. It should be noted that the Young forming such a wall 5a
Materials having a rate of 50 GPa or more include alumina and silicon carbide.
Insulating ceramics mainly composed of silicon, silicon nitride, etc.,
Lead zirconate titanate, zirconate lanthanum titanate
Lead, magnesium niobate or a mixture of these
There are piezoelectric ceramics and single crystal alumina as main components.
Or metals such as Ni-based alloys and molybdenum,
Tension glass or the like can be used. The width W of the wall 5a is set to 0.05 mm or more.
When the width W is less than 0.05 mm, the wall 5
a is formed of a material having a Young's modulus of 50 GPa or more.
Is too thin, the partition wall 1A adjacent to the wall 5a is displaced.
Wall 5a is deformed by the pressure wave
To attenuate the pressure wave, the pressure reflected to the partition wall 1A
The force wave is applied to the partition wall 1 on the opposite side of the partition wall 1A from the wall 5a.
B is smaller than the pressure wave reflected by B,
Because there is a difference between the pressure waves acting on both sides of A,
Ink ejected from the ink ejection holes 15 communicating with the path 2A.
The discharge speed and discharge amount of the droplets at a position distant from the wall 5a.
Discharge from the ink discharge holes 15 communicating with the flow paths 2B and 2C
To the ink droplet ejection speed and ejection volume
Flaws, which are discharged from the ink discharge holes 15 communicating with the respective flow paths 2.
Variations and landing positions of the ejection speed and ejection amount of ink droplets
This is because the displacement cannot be eliminated. However
When the width W of the wall 5a exceeds 5 mm, the head element 18
Is increased, and the size of the head 20 is merely increased.
Therefore, the width W of the wall 5a is preferably set to 5 mm or less. Further, the wall 5a and the wall 5a
The width L of the partition wall 1A is determined by the width of the flow paths 2A, 2B, 2C,.
M is equivalent to that the wall 5a has a Young's modulus of 50 GPa or less.
It is made of the above material, and the width W of the wall 5a is 0.05
mm or more, the wall 5a and the wall 5a
The width L with the partition wall 1A is the width of the flow paths 2A, 2B, 2C,.
If it is longer than M, the wall 1A is displaced and
The generated pressure wave is reflected by the wall 5a and returns to the wall 1A.
Time is on the opposite side of the wall 5a across the partition wall 1A
The pressure wave reflected by the partition 1B returns to the partition 1A.
It is slower than the time to come, and the wall 5a and this wall
The width L of the partition wall 1A adjacent to 5a is equal to the width of the flow paths 2A, 2B,
When the width M becomes shorter than the width M of 2C,.
And the pressure wave generated by the wall 1A is reflected by the wall 5A.
Time until it returns to the wall 5a across the partition wall 1A
The pressure wave reflected by the partition 1B on the opposite side
It is shorter than the time to return to 1A,
Also in this case, pressure waves reach both side surfaces of the partition wall 1A adjacent to the wall 5a.
Because there is a time difference before reaching, next to the wall 5a
Ejected from the ink ejection holes 15 communicating with the corresponding flow path 2A.
And the amount of ink droplets discharged from the wall 5a
The ink discharge holes 15 communicating with the flow paths 2B and 2C
The difference between the ejection speed and ejection amount of the ink droplet
Can be discharged from the ink discharge holes 15 communicating with the respective flow paths 2.
Variations and landing positions of the ejection speed and ejection amount of ink droplets
This is because the displacement cannot be eliminated. In the present invention, "wall 5a and this wall 5a"
The width L between the partition wall 1A and the partition wall 1A adjacent to the flow path 5a is defined as
2C,... Is equivalent to the width M of the flow paths 2A, 2B,
2C, ... has the same width as the width M, but ± 15
The dispersion may be within the range of μm or less. Next, the ink jet recording head shown in FIG.
A method for manufacturing the claw 20 will be described. First, a ceramic plate or a glass is used as the insulating substrate 4.
Prepare a lath plate. Especially limited as a type of ceramic plate
Although not specified, for example, alumina, zirconia,
Insulating cell mainly composed of forsterite, zircon, etc.
Lamix is preferred. And, on this insulating substrate 4,
Laser processing such as a carbon dioxide gas laser
After drilling ink supply holes 8 and ink recovery holes 9 respectively,
The piezoelectric ceramic plate polarized in the thickness direction is
Align with a line at a predetermined position on the top,
Paste with an adhesive such as a system. Next, using a surface grinder, the piezoelectric ceramic
After cutting the plate to make the side shape trapezoidal,
A plurality of blades serving as channels 2 are formed on the piezoelectric ceramic
The grooves are arranged side by side. At this time, the wall that partitions the groove becomes the partition wall 1. Next, the upper half of the side surface of each partition 1 and the insulating group
On the plate 4, a vapor deposition method, a sputtering method, an ion plate
Aluminum film by film forming means such as
Metal film made of metal, palladium, nickel, gold, copper, etc.
The metal film deposited on the upper half of the side surface of the partition wall 1 is used for driving.
A metal film deposited on the insulating substrate 4 as well as the electrode 3
Is the lead 16 of the driving electrode 3, and
The drive electrode 3 and its lead 16 are made of silicon nitride, etc.
A protective film S is applied. Then, each partition 1, ink supply hole 8, and
The frame member 5 is placed on an insulating substrate so as to surround the ink collecting hole 9.
4 and airtightly bonded with epoxy adhesive etc.
In addition, the Young's modulus for partitioning the recess of the frame member 5 into three rooms is 5
A wall 5a made of a material of 0 GPa is
Airtightly bond with an adhesive such as silicone. Thereafter, a gold such as a Ni-based alloy or molybdenum is used.
The lid 12 made of a metal is placed in the
The partition wall 1 and the frame portion are aligned with the center of the road 2 in the width direction.
Bonded to the top surface of material 5 with an adhesive such as epoxy
Nozzle part made of resin such as polyimide resin on lid part 12
14 is bonded with an epoxy-based adhesive or the like. After this, the frame
Outside the material 5, the drive is placed on the insulating substrate 4 on which the lead 16 is formed.
Equipped with Iver IC17, wire connection with wire bonder
After that, the laser processing such as excimer laser
And the nozzle portion 14 communicates with each of the ink guide holes 13.
Can be obtained by opening the discharge hole 15.
You. According to the present invention produced by such a method,
In the head 20, all the partition walls 1 are made of the insulating substrate 4 and the nozzle plate 1.
Adhesively bonded by the same process with 1
Therefore, the rigidity of the adhesive layer can be made uniform,
Therefore, the rigidity of all the partition walls 1 can be made uniform.
In particular, the dimensional variation of the ink ejection holes 15 of the nozzle plate 11
Can also be reduced. Therefore, the same voltage is applied to the driving electrode 3.
In this case, it is possible to displace each partition 1 with the same displacement amount.
Can be ejected from each ink ejection hole 15.
The discharge speed and discharge amount of ink droplets can be the same,
Head with little variation in ink droplet ejection speed and ejection amount
20 can be provided. The present invention relates to a head having the structure shown in FIG.
It is not limited to only 20, for example, a flow path member
The number of head elements 18 provided in 10 is not limited to three, but is four.
The head element 18 may be an insulating substrate.
4 may also be arranged in the short side direction. Also, each
The wall 5 a constituting the head element 18 is integrated with the frame member 5.
Even if it is formed in, it is integrated by joining
May be used. The scope which does not deviate from the gist of the present invention
It goes without saying that changes and improvements can be made with. EXAMPLE Here, the ink jet recording head shown in FIG.
Young's modulus of the wall 5a of the door 20, the width of the wall 5a, and the wall 5a
The width L of the partition wall 1A adjacent to the wall 5a and the flow paths 2A, 2B,
The relationship between the width M of 2C,.
An experiment was conducted to determine the ability. First, as the insulating substrate 4, 65 mm × 25
1.2mm x 1mm x 1mm alumina ceramic plate
1.5 mm round hole ink supply hole 8 and ink recovery hole 9
Are arranged in a straight line by carbon dioxide laser with 6 each.
9.1mm x 3mm x 0.5mm after drilling
, Lead zirconate titanate polarized in the thickness direction
Supplying three piezoelectric ceramic plates whose main components are ink
1 mm on the insulating substrate 4 between the hole 9 and the ink collecting hole 9
Lined up at an interval and paste with epoxy adhesive
Attached. Next, the surface of the piezoelectric ceramic plate was
Cut off the end, and make an angle with the insulating substrate 4 of 60 °.
And a trapezoidal side surface.
The upper surface of the piezoelectric ceramic plate was ground to a height of 0.45
mm. Further, a diamond boss having a thickness of 70 μm
Perpendicular to the long side of the piezoelectric ceramic plate
To a depth of 0.45mm and a pitch of 0.14mm
192 flow channels 2 having a width M of 0.075 mm are formed.
Was. Next, the upper half of the side surface of the partition wall 1 is formed by a vacuum evaporation method.
The drive electrode 3 is formed by applying an aluminum metal film
At the predetermined position on the insulating substrate 4.
The lead wire 16 of the driving electrode 3 is formed by depositing a metal film of
After the formation, the inner wall surface of the flow path 2 is further sputtered.
Thus, a protective film S of silicon nitride was applied. The outer shape is 50 mm × 17 mm and the inner shape is
The shape is 30mm x 13mm and the thickness is 0.45mm
The frame member 5 made of Ni alloy is divided into the partition walls 1 and the ink supply holes 8.
And on the insulating substrate 4 so as to surround each ink collecting hole 9.
Airtightly bonded with epoxy adhesive, and both ends of flow channel 2 and frame
A space formed by the member 5 is used as an ink reservoir,
Next, in the frame member 5 on the insulating substrate 4, Ni alloy, titanium
Lead zirconate-based piezoelectric ceramics (PZT), and
The frame member 5 is completed by joining the walls 5a made of polyimide resin.
The 192 channels 2 were cut into three equal parts. Then, on the top surfaces of the frame member 5 and the partition wall 1,
The shape is 50mm × 17mm × 0.07mm.
And guide the ink having a diameter of about 60 μm communicating with each flow path 2.
Epoxy bonding of Ni alloy lid 12 with holes 11
And the outer shape is 50 mm on the lid 12.
X 13 mm x 0.05 mm polyimide grease film
The nozzle portion 14 was joined with an epoxy adhesive. Next, the lead wire 1 formed on the insulating substrate 4
6 on which a driver IC 17 is mounted and a wire bonder
And connect the ink with an excimer laser.
Ink ejection hole with a diameter of about 28 μm communicating with the guide hole 11
15 is perforated in the nozzle portion 14 so that the number of nozzles is 1
Ninety-two inkjet recording heads 20 were produced. Then, one head of the obtained head 20 is obtained.
Supplies the sodian ink to the ink ejection element 1
Ink droplets are continuously ejected from 5 and adjacent to the wall 5a
Channel 2 and ink droplets ejected from channel 2 distant from the wall
Of ink droplet ejection speed for experiments comparing ink ejection speeds
Ejects ink droplets 100,000 times consecutively at 5 kHz.
While the ink is ejected from the predetermined ink ejection hole 15
Ink droplets at a fixed interval with a high-speed camera.
The ejection speed of the ink droplet is determined from the distance between the ejection hole 15 and the ink droplet.
Calculated. The results are as shown in Table 1. [Table 1] As a result, as can be seen from Table 1, the wall 5a
For PZT and Ni alloy materials with Young's modulus of 50 GPa or more
And the width of the wall 5a is 0.05 mm or more.
And the width between the wall 5a and the partition 1 adjacent to the wall 5a
The same width as the width of the passage 2 corresponds to the passage 2 and the wall adjacent to the wall 5a.
5a and ink ejected from flow path 2 remote from
Small difference in droplet ejection speed and extremely small ejection variation
I understand that. As a result, like the head 20 shown in FIG.
In the structure with ink reservoirs at both ends of the flow path
To eject multiple colors of ink from one head.
When the wall 5a is made of a material having a Young's modulus of 50 GPa or more,
And the wall 5a has a width of 0.05 mm or more.
And the width between the wall 5a and the partition wall 1 adjacent to the wall 5a
It can be seen that it suffices if the width is formed to be approximately equal to the width of No. 2. As described in detail above, the ink jet of the present invention
According to the recording head, a plurality of through holes are formed on the insulating substrate.
A frame member having a
The bottom of the recess formed by the edge substrate
A plurality of partition walls are arranged side by side at equal intervals, and
And both ends of each partition and the frame
The space formed by the members is used as an ink reservoir,
On the side surface of the partition, a flow path member having a driving electrode formed thereon,
Joined to the top surface of the frame member and each partition, and communicates with each flow path
A nozzle plate having ink discharge holes,
The Young's modulus of the wall that partitions at least the adjacent through holes of the material
It is made of a material of 50 GPa or more and the width of the wall
Is at least 0.05 mm, and the wall is adjacent to this wall.
The width of the partition wall is made equal to the width of the flow channel.
Can be connected to multiple inkjet recording heads.
Head element, so that each head
By supplying different colors of ink to the printing elements, color printing
And the displacement of the bulkhead next to the wall can be
Because it can be displaced in the same way as a wall,
Ink droplets discharged from ink discharge holes
Can print beautiful and clear images.
Can be. Also, the ink jet recording head of the present invention
According to the above, since the ink reservoirs are provided at both ends of the flow path,
Discharge of ink droplets compared to one with both ends of the flow path closed
The interval can be shortened, and the ink
Flow can be generated, so that air bubbles and
Prevent stagnation of ink agglomerates etc. and discharge ink droplets
To prevent the ejection speed from dropping and clogging of the ink ejection holes.
And the substrate forming the flow path member is insulated.
Since it is made of a material, the capacitance of the flow path
To reduce the power consumption of inkjet printheads
You can also.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partially cutaway perspective view showing an ink jet recording head of the present invention. FIGS. 2A and 2B are cross-sectional views for explaining the driving principle of the ink jet recording head of the present invention. FIG. 3 is an enlarged sectional view of a portion E in FIG. 1; FIG. 4 is a partially broken perspective view showing a conventional ink jet recording head. [Description of Signs] 1: Partition wall 2: Flow path 3: Driving electrode 4: Insulating substrate
5: Frame member 5a: Walls 6, 7: Ink reservoir 8: Ink supply hole 9: Ink recovery hole 10: Flow path member 11: Nozzle plate 12: Lid 13: Ink guide hole 1
4: Nozzle part 15: Ink ejection hole 16: Lead wire of drive electrode 1
7: Driver IC 18: Head element S: Protective film W: Width of wall L: Width of wall and partition wall adjacent to wall M: Width of flow path

Claims (1)

Claims: 1. A frame member having a plurality of through holes is joined to an insulating substrate, and a piezoelectric ceramic is formed on a bottom surface of a concave portion formed by the through hole of the frame member and the insulating substrate. A plurality of partition walls are arranged in parallel at equal intervals, and a space formed between both ends of the partition walls and the frame member is used as an ink reservoir, while a space between the partition walls is used as an ink flow path. A channel member provided with a driving electrode, and a nozzle plate provided with ink ejection holes that are joined to the top surface of the frame member and the partition walls and communicate with the respective flow channels, at least adjacent to the frame member. The width of the wall partitioning the matching through hole is 0.05 mm or more, the Young's modulus is 50 GPa or more, and the width of the wall and the partition wall adjacent to the wall is equal to the width of the flow path. Inkjet recording head.