JPH03184863A - Ink jet recording head and production of said head - Google Patents

Abstract

PURPOSE:To prevent a failure in delivery by a method wherein a delivery port forming member formed by laminating members having different values of internal stress is perforated to be provided with a delivery port. CONSTITUTION:In the production of an ink jet recording head provided with delivery port forming members 40a, 40b on which a delivery port 41 for delivering ink liquid drops is formed, the delivery port forming members 40a, 40b are constructed by laminating a plurality of different members, internal stresses having magnitudes different from each other are respectively generated in the plurality of different members before or after the laminating operation, and the delivery port 41 is formed on the laminated delivery port forming members 40a, 40b. When the delivery port forming members constructed as the above are subjected to perforating machining to be provided with the delivery port, a stress relaxation causes the pore part of the delivery port forming members to be bent as a whole toward the large-internal stress side. In this manner, the delivery port can be formed into a shape decreasing in cross sectional area in the ink liquid drop delivery direction.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an inkjet recording head, and more particularly, the present invention relates to an inkjet recording head that includes an ejection port forming member (hereinafter also referred to as an orifice plate) in which ejection ports for ejecting ink are formed. The present invention relates to an inkjet head.

[Prior Art] The main parts of this type of inkjet recording head include an orifice plate 40 provided with orifices 41 (ejection ports) for ejecting ink, as shown, for example, in FIGS. Ink liquid path 1 communicating with the orifice
101, and a substrate 100 that forms part of the ink liquid path 401 and has an electrothermal conversion element 101 that generates ejection energy.

The orifice provided in the orifice plate is minute, and this orifice is an important element that influences the ejection performance of the inkjet recording head. Therefore, the orifice plate requires performance such as good workability in order to provide minute orifices, and good ink resistance since it comes into direct contact with ink.

Conventionally, SUS has been used as a material that satisfies the above performance.

Metal plates such as nickel, Cr, and AI, as well as PPI, PES, and PEE, which can easily and inexpensively achieve the desired thickness.
Silk film materials such as K and PE were used.

On the other hand, with recent advances in recording technology, high-speed, high-definition recording is becoming required, and for this reason, orifices are being formed with minute sizes (orifice diameters) and high density. It's starting to look like this. As a result, various methods of orifice processing have been devised, and among them, processing using laser light is suitable for microfabrication and is therefore also used for orifice processing.

However, it is extremely difficult to join the orifice plate, in which minute orifices are formed, and the recording head body, in which ink channels are formed corresponding to each orifice, and some misalignment between the orifices and the ink channels may occur. In some cases, the ejection performance deteriorated and the recording quality deteriorated.

Furthermore, although some kind of adhesive is used for bonding, the adhesive may sometimes block the ink liquid path during bonding due to misalignment.

For this reason, recently a method has been adopted in which a resin film as the material for the orifice plate is bonded to the head body and then the orifice is processed using laser light.

[Problems to be Solved by the Invention] However, conventional recording head processing methods and head configurations have had various problems as described below.

That is, the shape of the orifice of the inkjet recording head is preferably a tapered shape in which the diameter becomes smaller toward the direction in which ink droplets are ejected, from the viewpoint of stability of ejection direction and ejection speed. However, when performing laser processing on a film made of a single material, there is a problem in that the film becomes tapered in the opposite direction, with the diameter decreasing toward the ink liquid path, as shown in FIG.

Additionally, there is a problem with the numerical structure of the inkjet recording head, such as if the orifice of the inkjet recording head gets stuck or clogged, causing unstable ejection, resulting in a decline in recording quality and defects in the recording. Sometimes it happened.

The present invention has been made to solve the above-mentioned problems, and by forming an orifice in an orifice plate constructed by layering multiple types of materials, the difference in stress that occurs when processing a recording head of these materials can be reduced. An object of the present invention is to provide a method for manufacturing an inkjet recording head and a recording head that can make the orifice shape appropriate by utilizing the following.

[Means for Solving the Problems] Therefore, in the present invention, in a method for manufacturing an inkjet recording head including an ejection port forming member provided with an ejection port for ejecting ink droplets, the ejection port forming member includes: a step of constructing by laminating a plurality of different members, a step of generating internal stress of a mutually different magnitude between the members in each of the plurality of different members before or after the lamination, and a step of constructing by the lamination. forming an ejection port on the ejection port forming member.

More preferably, the ejection port forming member is formed by laminating two different members, and the layer on the side opposite to the ink droplet ejection direction of the laminated layer is formed of a member having curing shrinkage property, and It is characterized in that by hardening the member, a larger internal stress is generated than that of the other member to be laminated.

[Function] According to the above configuration, when drilling is performed to form a discharge port (orifice) in the discharge port forming member (orifice plate) formed by laminating members with different internal stresses, stress relaxation occurs. As a result, the hole portion of the discharge port forming member is bent as a whole in the direction of the larger internal stress.

As a result, it is possible to obtain, for example, a shape of the ejection port whose cross-sectional area becomes smaller in the direction in which ink droplets are ejected, and the position of the ejection port can also be set back from the surface of the ejection port forming member.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a perspective view of an inkjet recording head according to an embodiment of the present invention, and is a disposable head with an integrated ink tank.

The inkjet recording head shown in the figure is made by bonding a silicon substrate (hereinafter referred to as a heater board) to a top plate integrally formed with grooves for configuring an ink liquid path and a common liquid chamber, as shown in Fig. 5. Recording head body (not shown)
As shown in the figure, orifice plates 40a and 40b are bonded to the opening surface on which the opening of the ink liquid path formed by this bonding is arranged. On the St substrate, an electrothermal conversion element (hereinafter referred to as a discharge heater) that generates discharge energy and aluminum wiring for supplying an electric signal to the element are formed using a film forming technique.

Further, 600 in the figure is a sub-ink tank disposed adjacent to the recording head main body, and this sub-ink tank 600
and said body is supported by M2O3 and 800. Furthermore, 1000 is a cartridge main body, and 1100 is a lid member of the cartridge main body.

An ink tank is built inside the cartridge main body, and ink is appropriately supplied to the sub-ink tank 600.

FIG. 2 is a side sectional view of the main part of an inkjet recording head according to an embodiment of the present invention. In the figure, 40a is one of the orifice plates made of two types of materials, and 40b is the other orifice plate. In this embodiment, the material of the plate 40a is a PE film with a thickness of about 20 μm. Also, plate 40
b may be any material that has curing shrinkage, but in this embodiment, it is formed using an adhesive having the composition shown below, which also serves as an adhesive layer for bonding the opening surface of the ink liquid path and the plate 40a. did. Its composition is Epicote 828 (oiled shell epoxy) = 2 ethyl 4 methyl ikdazole = 10:4
It is.

A method of manufacturing the above recording head will be described below.

After applying the adhesive to form the plate job to the PE film serving as the plate 40a using a spinner or roll coater, it is first semi-cured (100°C for 5 minutes), and then the PE film is bonded to the opening surface of the ink liquid path and cured ( 120℃4
time or 1 hour at 140° C.) to generate stress.

Next, an orifice is formed in the recording head to which the orifice plates 40a and 40b are bonded using a laser beam. In this example, excimer laser light was used. In this process, as shown in FIG. 3, first, a stainless steel mask 9 having holes 91 corresponding to the shape and arrangement of the orifice is used, and the opening of the ink liquid path and the hole 91 of the mask 9 are connected to each other. 0, the mask 9 is irradiated with excimer laser light for several seconds. The portions of the orifice plates 40a and 40b that have been irradiated with excimer laser light are removed to form orifices 41. At this time, the plate 40b tends to shrink due to the shrinkage stress generated during the curing process described above, and due to the relationship between this force and the adhesive force with the plate 40a, the orifice plates 40a and 40b bend toward the ink liquid path side.
An orifice 41 having a shape as shown in the figure is formed.

As shown in FIG. 2, the shape in which the diameter becomes smaller toward the tip has the effect of increasing and stabilizing the ejection speed, as described above, and leads to an improvement in the quality of the recorded image. Furthermore, the orifice is located at d shown in Fig. 2 on the ink liquid path side from the plane before processing.
The structure has a receding position, which is effective in preventing ejection failures due to dust adhesion, etc. Furthermore, by changing the combination of plates 40a and 4 (lb), the orifice shape can be easily and freely controlled depending on the degree of stress generation.

Further, although the plates 40a and 4 (lb) are cured and shrunk after being bonded together as in the above embodiment, a step of generating internal stress may be provided before bonding the plates 1 to each other.

The recording head described above can be obtained in the form of a cartridge as shown in FIG. 1, and can be used to create, for example, an inkjet printer as shown in FIG.
It is possible to configure an inkjet printer to which a disposable cartridge can be attached.

4 is the cartridge shown in FIG. 1, and this cartridge 8 is fixed on the carriage 15 with a holding member 81. These are capable of reciprocating in the longitudinal direction along the shaft 21. Further, positioning with respect to the carriage 15 is performed, for example, by a hole provided in the lid 300 and a dowel provided on the carriage 15 side. Further, electrical connection can be made by connecting a connector on the carriage 15 to a connection pad provided on the wiring board.

The ink ejected from the recording head reaches the recording material 18 whose recording surface is regulated by the platen 19 at a small distance from the recording head, and forms an image 2 on the recording material 18.

The recording head is supplied with an ejection signal corresponding to data from an appropriate data supply source via a cable I6 and a terminal coupled thereto. One or more cartridges 8 (two in the figure) can be installed depending on the ink color used.

Further, in FIG. 4, 17 is a carriage motor for scanning the carriage 15 along the shaft 21;
is a wire that transmits the driving force of the motor 17 to the carriage 15. Further, 20 is a feed motor coupled to the platen roller 19 for conveying the recording material 18.

(Others) The present invention brings about excellent effects particularly in a bubble jet type recording head and recording apparatus among inkjet recording types.

This is because such a system can achieve higher recording density and higher definition.

As for typical configurations and principles thereof, it is preferable to use the basic principles disclosed in, for example, US Pat. No. 4,723,129 and US Pat. No. 4,740,796. This method can be applied to both the so-called on-demand type and continuous type, but especially in the case of the on-demand type, it is necessary to arrange the liquid (ink) in accordance with the sheet and liquid path that hold it. By applying at least one drive signal that corresponds to recorded information and causes a rapid temperature rise exceeding nucleate boiling to the electrothermal transducer, the electrothermal transducer generates thermal energy, and the recording head This is effective because it causes film boiling on the heat acting surface of the drive signal, resulting in the formation of bubbles in the liquid (ink) that correspond one-to-one to this drive signal. The growth and contraction of the bubble causes liquid (ink) to be ejected through the ejection opening to form at least one droplet. It is more preferable to use this drive signal in a pulse form, since the growth and contraction of bubbles can be carried out immediately and appropriately, making it possible to eject liquid (ink) with particularly excellent responsiveness. This pulse-shaped drive signal is:
U.S. Pat. No. 441i3359, U.S. Pat. No. 43452
4 as described in specification No. 82 is suitable. Furthermore, if the conditions described in US Pat. No. 4,313,124 concerning the invention regarding the temperature increase rate of the heat acting surface are adopted, even more excellent recording can be performed.

The configuration of the recording head includes a combination configuration of an ejection port, a wave path, and an N air heat converter (a linear liquid flow path or a right-angled liquid flow path) as disclosed in the above-mentioned specifications, as well as a heat acting section. U.S. Pat. No. 4,558,333 and U.S. Pat. No. 4,459fi00 disclose a configuration in which the
The present invention also includes a configuration using the specification of the above specification.

In addition, Japanese Patent Laid-Open No. 59123670 discloses a configuration in which a common slit is used as a discharge part of a plurality of electrothermal converters, and an aperture that absorbs pressure waves of thermal energy is used as a discharge part. Japanese Unexamined Patent Application Publication No. 1983-1987 discloses a configuration that corresponds to
The effects of the present invention are also effective even if the structure is based on the publication No.-138461. In other words, regardless of the form of the recording head, recording can be performed reliably and efficiently.

Furthermore, the present invention can be effectively applied to a full-line type recording head having a length corresponding to the maximum width of 5 mm on a recording medium that can be recorded by a recording apparatus.

Such a recording head may be constructed by combining a plurality of recording heads to shorten the length, or may be constructed as a single recording head formed integrally. In addition, even the serial type shown above can be installed on the main body of the device, allowing for electrical connection to the main body of the device and supply of ink from the main body of the device. Alternatively, the present invention is also effective when using a cartridge type recording head that is integrally provided with the recording head itself.

Further, it is preferable to add recovery means for the recording head, preliminary auxiliary means, etc., which are provided as a configuration of the recording apparatus, to the present invention because the effects of the present invention can be further stabilized. Specifically, these include capping means for the recording head, cleaning means, pressure or suction means, preheating means using an electrothermal transducer or another heating element, or a combination thereof; record and
6, it is also effective to perform a preliminary ejection mode in which another ejection is performed in order to perform stable recording.

In addition, regarding the type and number of recording heads installed, for example, in addition to one type that corresponds to single-color ink, there is also a plurality of recording heads that correspond to multiple inks with different recording colors and densities. It may be something that can be done.

In addition, in addition to being used as an image output terminal for information processing equipment such as a computer, the inkjet recording apparatus of the present invention may also take the form of a copying machine combined with a league, etc., or a facsimile machine having a transmission/reception function. It may be something.

[Effects of the Invention] As is clear from the above description, according to the present invention, a discharge port (orifice) is formed in a discharge port forming member (orifice plate) formed by laminating members having different internal stresses. When the holes are drilled, the seven holes of the discharge port forming member are bent as a whole in the direction of the larger internal stress due to stress relaxation.

As a result, it is possible to obtain, for example, an ejection opening shape that faces in the ejection direction of ink droplets and has a smaller cross-sectional area.
The position of the ejection port can also be set back from the surface of the ejection port forming member.

As a result, ejection failures caused by dust or the like can be prevented.

Further, by simply performing conventional ejection port (orifice) processing on a previously formed ejection port forming member (orifice plate), it is possible to obtain a highly reliable inkjet recording head with superior ejection performance than before.

[Brief explanation of drawings]

FIG. 1 is an external perspective view of an inkjet recording head cartridge according to an embodiment of the present invention, FIG. 2 is a side sectional view of the main parts of the recording head constituting the cartridge shown in FIG. 1, and FIG. FIG. 4 is a perspective view showing an example of an inkjet printer equipped with a recording head cartridge according to an embodiment of the present invention; FIGS. The figures are an exploded perspective view and a side sectional view, respectively, showing a conventional example of an inkjet recording head. 40a, 40b... Orifice plate (discharge port forming member), 41... Orifice (discharge port), 100... Substrate (heater board), 101... Electrothermal conversion element, 400... Top plate , 401... Ink liquid path. Diagram

Claims (1)

[Claims] 1) A method for manufacturing an inkjet recording head including an ejection port forming member provided with an ejection port for ejecting ink droplets, comprising laminating a plurality of different members for the ejection port forming member. a step of generating internal stresses of mutually different magnitudes in each of the plurality of different members before or after the lamination; and a step of forming an ejection port forming member formed by the lamination. 1. A method of manufacturing an inkjet recording head, comprising: forming an ejection port. 2) The ejection port forming member is formed by laminating two different members, and the layer on the opposite side of the ink droplet ejection direction of the laminated layer is formed of a member having curing shrinkage, and the member is hardened. 2. The method of manufacturing an ink jet recording head according to claim 1, wherein a larger internal stress is generated than that of the other member to be laminated. 3) The method of manufacturing an inkjet recording head according to claim 1, wherein the ejection ports are formed using excimer laser light. 4) An inkjet recording head manufactured by the manufacturing method according to any one of claims 1 to 3. 5) The inkjet recording head or inkjet recording according to any one of claims 1 to 4, wherein the recording head discharges the ink droplets using thermal energy generated by an electrothermal conversion element. Head manufacturing method.