JP2633943B2 - Ink jet recording head and method of manufacturing the head - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording head and a method of manufacturing the recording head, and more particularly, to a discharge port forming member (hereinafter, an orifice) having a discharge port (hereinafter, an orifice) formed. Plate) and a method for manufacturing the same.

[Related Art] Recently, an excimer laser beam has been used to process an orifice of a recording head of this type. The orifice processing by the excimer laser light has been performed by bonding a resin film to be an orifice plate to an opening surface provided with an opening communicating with an ink liquid path, and then irradiating the excimer laser light.

This is shown in FIG. In the figure, 1 is an excimer laser device, 2 is a laser beam oscillated from the excimer laser device, 3 is a lens for collecting the laser beam, 4 is a mask having all or a part of an orifice pattern, Reference numeral 5 denotes an ink jet recording head main body in which a resin film is joined to the opening surface of the ink liquid passage, and reference numeral 6 denotes a movable stage.

FIG. 9 shows the details of the ink jet recording head main body 5 whose orifice has been processed by such a device configuration. FIG. 9 is a sectional view of the head body. In this figure, 7 is a top plate on which a groove for forming an ink liquid path is formed, 8 is a substrate on which ejection energy generating elements are patterned, 9 is an opening communicating with the ink liquid path, and 10 is a resin film. The orifice plate 11 is an orifice formed in the orifice plate 10.

Reference numeral 14 denotes an ink liquid path, and reference numeral 15 denotes an electrothermal converter as an ejection energy generating element.

As shown in FIG. 9, in the orifice processing by the conventional excimer laser as shown in FIG. 8, the shape of the orifice becomes a tapered shape in which the side of the discharge port is widened.

[Problems to be Solved by the Invention] However, the ink jet recording head having such a tapered orifice expanding toward the ejection port has the following problems.

That is, if the orifice has the above-described shape, the ejection characteristics become unstable, such as a case where the amount of ink droplets and the ink ejection speed required for recording an image or the like may not be sufficiently obtained, and recording may become unstable. In some cases, the quality of the image is reduced.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described conventional problems. By forming the tapered shape of the orifice so that the ejection port side is narrowed, the amount and ejection speed of ink droplets required for recording are reduced. An object of the present invention is to provide an ink jet recording head which can be obtained stably and sufficiently, and a method for manufacturing the same.

[Means for Solving the Problems] For this purpose, in the present invention, a substrate on which a discharge energy generating element for generating discharge energy used for discharging ink is formed, and the discharge energy element is arranged by bonding to the substrate Ink jet recording comprising a top plate having a concave portion for forming an ink liquid passage corresponding to a portion, and a discharge port forming member formed with a discharge port for discharging ink in communication with the ink liquid passage. The method for manufacturing a head is characterized in that after the top plate and the discharge port forming member are integrated, the discharge ports are formed by irradiating excimer laser light from the concave side.

[Operation] According to the above configuration, it is possible to obtain an ink jet recording head having a tapered orifice whose cross-sectional area is reduced in the ejection direction. Speed can be obtained stably.

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

FIG. 1 shows an ink jet recording head according to one embodiment of the present invention, which is a disposable one in which an ink tank is integrated.

The ink jet recording head shown in the figure has a top plate integrally formed with a concave portion (hereinafter referred to as a groove) for forming an ink liquid path and a common liquid chamber and an orifice plate 10, and an electrothermal converter for generating ejection energy. A recording head formed by bonding a body (hereinafter, discharge heater) and an Al wiring for supplying an electric signal thereto to a substrate (hereinafter, heater board) formed into a Si substrate by a film forming technique. A body (not shown) is provided.

In the figure, reference numeral 600 denotes a sub ink tank disposed adjacent to the recording head main body.
And the body is supported by lids 300 and 800.
Further, reference numeral 1000 denotes a cartridge main body, and 1100 denotes a lid member of the cartridge main body. An ink tank is built in the cartridge body, and supplies ink to the sub ink tank 600 as appropriate.

FIG. 2 shows a state in which an orifice plate formed integrally with the top plate is irradiated with an excimer laser beam from the ink liquid path side to perform orifice processing. Elements similar to those shown in FIG. 7 are shown. Are given the same reference numerals. In the figure, reference numeral 1 denotes a laser oscillation device that oscillates a KrF excimer laser beam, 2 denotes a pulse laser beam having a wavelength of 248 mm and a pulse width of about 15 nsec,
Is a synthetic quartz lens for collecting the laser beam 2,
Reference numeral 4 denotes a projection mask formed by evaporating aluminum capable of shielding the laser beam 2, and a hole having a diameter of 133 μm is 212 μm.
A plurality of m-pitch orifices are arranged to form an orifice pattern.

FIGS. 3A and 3B are a plan view and a partially enlarged view of a substrate (heater board) 8 according to the present embodiment.

In FIG. 1A, reference numeral 101 denotes a heater board base according to the present example, and 103 denotes a discharge heater section. A terminal 104 is connected to the outside by wire bonding. Reference numeral 102 denotes a temperature sensor, which is formed on the discharge heater unit 3 by the same film forming process as that of the discharge heater unit 103 and the like. FIG. 1B is an enlarged view of a portion B including the sensor 102 in FIG. 1A, and reference numerals 15 and 106 denote a discharge heater and wiring, respectively. Reference numeral 108 denotes a heater for heating the head.

Since the sensor 102 is formed by a film forming process similar to that of a semiconductor similarly to the other parts, it has extremely high accuracy, and aluminum, titanium,
It can be made of a material whose conductivity changes according to temperature, such as tantalum, tantalum pentoxide, and niobium. For example, among these, titanium is a material that can be disposed between the heating resistance layer and the electrode constituting the electrothermal conversion element in order to enhance the adhesiveness between the two,
Tantalum is a material that can be placed on the protective layer on the heating resistor layer in order to increase the cavitation resistance of the protective layer. Further, the line width is increased in order to reduce process variations, and the resistance is increased in a meandering shape in order to reduce the influence of wiring resistance and the like.

Similarly, the heat retaining heater 108 can be formed using the same material (for example, HfB ₂ ) as the heat generating resistance layer of the discharge heater 15, but using another material forming the heater board, for example, aluminum, tantalum, titanium or the like. It may be formed.

 FIG. 4A shows a configuration example of the top plate 7 according to this example.

The top plate 7 according to the present example has a desired number of ink passage grooves 14 and the corresponding number of ink ejection ports (orifices) 11 formed in the orifice plate 10 (two in the figure for simplicity). And the orifice plate 10 is provided integrally.

In the configuration example shown in FIG. 4A, the top plate 7 is made of a resin such as polysulfone, polyethersulfone, polyphenylene oxide, or polypropylene having excellent ink resistance, and is put together with the orifice plate 10 in a mold. Simultaneously molded together.

Next, a method of forming the ink liquid channel 14 and the orifice 11 will be described.

As for the ink liquid channel, the resin is molded using a mold in which fine grooves of the reverse pattern are formed by a method such as cutting.
Thereby, the liquid path groove 14 can be formed in the top plate 7.

As for the formation of the orifice, the orifice 11 is formed in the mold without the orifice 11, and the orifice plate is formed at the position where the orifice should be formed as described in FIG.
An excimer laser beam is irradiated from the ink liquid path side of the laser beam by a laser device to remove and evaporate the resin, and the orifice 11
To form

The details of the orifice formation are shown in FIG. 4 (B). As is apparent from the drawing, the excimer laser beam 2 is applied to the orifice plate 10 from the ink liquid path 14 side by the mask 4 described above.
Irradiated via The excimer laser light 2 is
Light is collected at one side θ ₁ = 2 degrees with respect to the optical axis 13, and is irradiated with the optical axis 13 inclined at θ ₂ = 10 degrees from the vertical direction of the orifice plate 10.

As described above, by irradiating the laser beam from the ink liquid path side, the cross-sectional area of the orifice having the tapered shape is reduced toward the ejection direction.

Here, the excimer laser light used in this example will be described.

This excimer laser is a laser that can oscillate ultraviolet light, such as high intensity, good monochromaticity, directivity, short pulse oscillation, and extremely high energy density by focusing with a lens. Has advantages.

Excimer laser oscillators are devices that can oscillate short-pulse (15-35 ns) ultraviolet light by discharging and exciting a mixed gas of rare gas and halogen. Kr-F, Xe-Cl, and Ar-F lasers are often used. Can be These oscillation energies are several hundred mJ / pulse, and the pulse repetition frequency is 30-1000 Hz.

When high-brightness short-pulse ultraviolet light such as excimer laser light is applied to the polymer resin surface, the irradiated part instantaneously decomposes and scatters with plasma emission and impact sound.
The ve Photodecomposition (APD) process occurs, which allows the processing of the polymer resin.

In this way, when the processing accuracy of an excimer laser is compared with that of another laser, for example, polyimide (P
I) Laser as excimer laser on film and other Y
When irradiating with AG laser or CO ₂ laser, a beautiful hole is opened by KrF laser because the wavelength of absorbing PI light is in the UV region, but with a YAG laser not in the UV region, the hole surface is opened but the edge surface is roughened and infrared light is emitted. Some CO ₂ lasers create craters around holes.

The metal such as SUS, opaque ceramics, S _i, etc. in an atmosphere of air, because it is not affected by the irradiation of the excimer laser beam, it can be used as a mask material in the processing by an excimer laser.

FIG. 5 is a perspective view of a recording head main body formed by joining the above-described heater board 8 and the top plate 7.

As shown in the figure, a heater board 8 having a discharge heater 15 and the like is brought into contact with the orifice plate 10 and joined to obtain a recording head body.

In the above-described configuration, since alignment and bonding between the top plate and the orifice plate are not required as in the related art, there is no alignment error or misalignment at the time of bonding, thus reducing defective products and shortening the process. This contributes to mass production of the recording head and cost reduction. Further, since there is no step of bonding the top plate and the orifice plate as in the related art, there is no possibility that the orifice or the ink flow path is blocked due to the flow of the adhesive. Furthermore, when the heater board 8 and the orifice plate 10 are joined together with the top plate 7 in an integrated manner, the heater board 8 can be abutted against the end face of the orifice plate 10 opposite to the end face on the discharge side, so that positioning in the channel direction can be performed. In addition, the entire positioning process and the assembling process are facilitated. In addition, there is no possibility that the orifice plate is peeled off as in the related art.

6 (A) and 6 (B) show another embodiment of the present invention, and are a perspective view and a sectional view of a top plate integrally formed with an orifice plate.

This example irradiation angle in accordance with the shape of the top plate and the orifice plate, that is, those with ₂ to 45 degrees θ described above. That is, when irradiating the laser light from the ink liquid path side, the irradiation angle is changed according to the shape of the top plate or the like.

The following table shows a comparison of the results of recording performed by the recording head constructed according to the above two embodiments and the conventional recording head as shown in FIG.

As is clear from the above table, when the recording head according to the present example is used, the ejection speed increases more than twice, and as a result, the landing position accuracy of the droplet is improved, and a good recording result can be obtained. . In addition, it is also understood that the volume of the ejected droplet increases when the orifice has an orifice shape as in this example,
This gives good results for the recording density.

In the above two embodiments, the orifice plate is integrated with the top plate, but the application of the present invention is not limited to this, and the orifice plate is separately joined to the top plate, and then the orifice processing as described above is performed. It goes without saying that a predetermined effect can be obtained even if it is performed.

The recording head body described above can be obtained in the form of a cartridge as shown in FIG. 1, and further, using this, an ink jet printer as shown in FIG.
An ink jet printer using a disposable cartridge can be configured.

In FIG. 7, reference numeral 80 denotes the cartridge shown in FIG. 1. The cartridge 80 is fixed on the carriage 51 by a pressing member 81.
Can be reciprocated in the longitudinal direction along. The positioning with respect to the carriage 51 can be performed by, for example, a hole provided in the lid 300, a dowel provided on the carriage 15 side, or the like. Further, for electrical connection, a connector on the carriage 51 may be connected to a connection pad provided on the wiring board.

The ink discharged by the recording head reaches the recording medium 18 whose recording surface is regulated by the platen 19 at a minute interval from the recording head, and forms an image on the recording medium 18.

An ejection signal corresponding to image data is supplied to the recording head from a suitable data supply source via a cable 16 and a terminal connected thereto. One or more (two in the figure) cartridges 80 can be provided depending on the ink color and the like to be used.

In FIG. 7, reference numeral 17 designates a carriage 51 as a shaft.
A carriage motor for scanning along 21 and a wire 22 for transmitting the driving force of the motor 17 to the carriage 51. Reference numeral 20 denotes a recording medium connected to a platen roller 19.
Is a feed motor for transporting the paper.

[Effects of the Invention] As is apparent from the above description, according to the present invention, it is possible to obtain an ink jet recording head having a tapered orifice that contracts in the ejection direction, thereby making it possible to obtain an ink necessary for recording. It is possible to stably obtain the amount and the discharge speed of the droplet.

As a result, the ejection performance such as the landing position accuracy of the ejected droplets and the recording density is improved, and a high-quality recorded image can be obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view of an ink jet recording head cartridge according to one embodiment of the present invention, FIG. 2 is a schematic configuration diagram of an orifice processing apparatus using excimer laser light, and FIGS. 3 (A) and (B) are the present invention. 4A and 4B are plan views and partial enlarged views, respectively, of a heater board according to an embodiment of the present invention. FIG. 5 is a perspective view and a cross-sectional view, FIG. 5 is a perspective view of an ink jet recording head body formed by joining the heater board shown in FIG. 3 and the top plate shown in FIG. 4, FIG. (B) is a perspective view and a cross-sectional view of a top plate integrated with an orifice plate showing another embodiment of the present invention. FIG. 7 is an ink jet mounting a recording head according to an embodiment of the present invention. FIG. 8 is a perspective view showing an example of a printer, FIG. 8 is a schematic configuration diagram of an orifice processing apparatus showing an example of a conventional example of processing an orifice by excimer laser light, and FIG. 9 is processed by the apparatus shown in FIG. FIG. 3 is a sectional view showing an orifice. DESCRIPTION OF SYMBOLS 1 ... Laser oscillator, 2 ... Laser beam, 3 ... Light collecting lens, 4 ... Mask, 7 ... Top plate, 8 ... Substrate (heater board), 10 ... Orifice plate, 11 ... Orifice , 13 ... optical axis, 14 ... ink liquid path, 15 ... discharge heater.

Claims (5)

(57) [Claims] 1. A substrate on which an ejection energy generating element for generating ejection energy used for ejecting ink is formed, and an ink liquid corresponding to a portion where the ejection energy element is provided by bonding to the substrate. A method of manufacturing an ink jet recording head, comprising: a top plate having a concave portion for forming a path, and a discharge port forming member formed with a discharge port for discharging ink in communication with the ink liquid path. A method of manufacturing an ink jet recording head, comprising: after integrating the top plate and the discharge port forming member, irradiating excimer laser light from the concave side to form the discharge ports. 2. The method according to claim 1, wherein the top plate and the discharge port forming member are formed integrally. 3. An ink jet recording head manufactured by the manufacturing method according to claim 1. 4. An ink jet recording head according to claim 3, wherein said discharge energy generating element is configured to apply heat energy to said ink. 5. An ink jet recording head according to claim 3, wherein said discharge energy generating element is an electrothermal transducer.