JPH02295748A - Liquid jet recorder - Google Patents

Abstract

PURPOSE:To achieve stabilized repeating delivery performance by surrounding the side of a thermal energy functioning section for thermally producing bubbles of recording liquid which is not jointed to the electrode of thermal resistor, with member having high thermal conductivity. CONSTITUTION:A thermal resistor 51 is formed through electron beam deposition. Al heat sinks are patterned onto the bottom face and the side face of a thermal resistor 2. Selective electrodes 5 are patterned on a substrate 1 as shown of fig. a. Then the heating resistor 2 is patterned, as shown on fig. c, while holding an insulating layer 6 between them. An opening 7 is made at a position of the insulating layer 6 corresponding with the selective electrode 5 and connected with the thermal resistor 2. Furthermore, a common electrode 4 is patterned, as shown on fig. d, so that the common electrode 4 surrounds the sides of the thermal resistor. When a protective layer for the thermal resistor 2 and a resin layer for protecting the electrode are provided, heat is radiated efficiently from the thermal functioning section or the heat producing section upon delivery of liquid drop through an orifice, thus cooling the liquid or the bubbles at the thermal functioning section quickly.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a liquid jet recording apparatus, and more particularly to a head section of a bubble jet printer.

The conventional non-impact recording method has recently attracted attention because the noise generated during recording is so small that it can be ignored. Among them, high-speed recording is possible,
However, the so-called inkjet recording method, which allows recording on plain paper without the need for special fixing treatment, is an extremely powerful recording method, and various methods have been proposed, improved, and commercialized. Some have been developed, and efforts are still being made to put them into practical use.

In this type of inkjet recording method, recording is performed by causing droplets of a recording liquid called ink to fly and adhere to a recording member. There are several types of methods depending on the control method used to control the flying direction of the generated recording liquid beads.

First, the first method is the one (Tele type method) disclosed in, for example, U.S. Pat. Recording is performed by controlling the droplets with an electric field in accordance with a recording signal to selectively attach recording liquid droplets onto a recording member.

More specifically, an electric field is applied between the nozzle and the accelerating electrode to eject uniformly charged recording liquid droplets from the nozzle, and the ejected recording liquid droplets are converted into recording signals. It flies between x and y deflection electrodes that are configured to be electrically controllable according to the ! ! Recording is performed by selectively depositing droplets on a recording member by changing the intensity of the field.

The second method is a method (Sweet method) disclosed in, for example, U.S. Pat. No. 3,596,275, U.S. Pat. Recording is performed on a recording member by generating droplets with a controlled amount of charge and flying the generated droplets between deflection electrodes to which a uniform electric field is applied.

Specifically, the orifice (discharge port) of the nozzle, which is a part of the recording head to which the piezo vibrating element is attached.
A charged electrode configured to have a recording signal applied thereto is placed at a predetermined distance in front of the piezo vibrating element, and an electric signal of a constant frequency is applied to the piezo vibrating element to mechanically vibrate the piezo vibrating element. , a small amount of recording liquid is ejected from the ejection port. At this time, a charge is electrostatically induced in the recording liquid droplet discharged by the charging electrode, and the small ridge is charged with an amount of charge corresponding to the recording signal. A droplet of recording liquid with a controlled amount of charge is deflected by a deflection current wA, which is uniformly applied with a constant electric field.
When the droplets fly between the recording members, they are deflected according to the amount of charge added, so that only the droplets carrying the recording signal can adhere to the recording member.

The third method is, for example, the method disclosed in U.S. Pat. No. 3,416,153 (Hertz method),
In this method, an electric field is applied between a nozzle and a ring-shaped IS electrode, and a continuous vibration generation method is used to generate and atomize small droplets of the liquid described in (a) for recording. That is, in this method, the atomization state of droplets is controlled by modulating the electric field intensity applied between the nozzle and the charging electrode in accordance with the recording signal, and the gradation of the recorded image is produced.

The fourth method is, for example, US Pat. No. 3,747,120
This method (Stemme method) is disclosed in 'lHF, and the principle of this method is fundamentally different from the above three methods.

That is, in all three methods, the droplets of recording liquid ejected from the nozzle are electrically controlled while they are in flight, and the droplets carrying the recording signal are selectively attached to the recording member. In contrast, this Stemme method
Recording is performed by ejecting small droplets of recording liquid from an ejection port in response to a recording signal.

In other words, the Stem+++e method applies an electrical recording signal to a piezo vibrating element attached to a recording head that has an ejection port for discharging recording liquid, and converts this electrical recording signal into mechanical vibration of the piezo vibrating element. Instead, recording is performed by ejecting and flying 4s droplets of recording liquid from the ejection port according to the mechanical vibrations and adhering them to the recording member.

These four conventional methods each have their own advantages, but there are also points that can be solved in the other method.

That is, in the first to third methods, the direct energy for generating droplets of the recording liquid is electrical energy, and the deflection control of the droplets is also controlled by electric field.

Therefore, although the first method is simple in structure, it requires a high voltage to generate droplets, and it is difficult to use a multi-nozzle recording head, making it unsuitable for high-speed recording.

The second method allows the recording head to have multiple nozzles and is suitable for high-speed recording. There are problems such as the tendency to generate dots.

The third method has the advantage of being able to record images with excellent gradation by atomizing recording liquid droplets, but on the other hand, it is difficult to control the atomization state and fog occurs in the recorded image. In addition, it is difficult to create a multi-nozzle recording head.
There are problems with the score, such as it being unsuitable for high-speed recording.

The fourth method has relatively many advantages compared to the first to third methods. That is, the configuration is simple, and since recording is performed by ejecting recording liquid from the ejection opening of the nozzle on-demand, the method of ejecting small droplets as in the first to third methods is simple. Second, it is not necessary to collect droplets that are not needed to record an image, and unlike the first and second methods, there is no need to use a conductive recording liquid, and the material of the recording liquid is It has great advantages such as a high degree of freedom. However, on the other hand, it is difficult to make the recording head multi-nozzle due to problems in the processing of the recording head and the extremely difficult miniaturization of piezoelectric vibrating elements having the desired resonance number. This method has disadvantages such as that it is not suitable for high-speed recording because the recording liquid droplets are ejected into flight using the mechanical energy of the mechanical vibration of the piezoelectric vibrating element.

Furthermore, Japanese Patent Application Laid-open No. 48-9622 (corresponding to the specification of US Pat. No. 3,747,120) includes, as a modification,
It is described that thermal energy is used instead of using mechanical vibration energy by means such as the piezo vibration element described above.

That is, the above-mentioned publication describes a so-called bubble jet liquid jet recording device that uses a heating coil that directly heats liquid as a pressure increasing means instead of a piezo vibrating element to generate steam that causes a pressure increase. There is.

However, in the above publication, the liquid ink in the bag-shaped ink chamber (liquid chamber), which has only one opening through which liquid ink can enter and exit, is directly heated and vaporized by energizing a heating coil as a means for increasing pressure. However, there is no suggestion as to how to heat the liquid when continuously and repeatedly discharging the liquid. In addition, the heating coil is located at the deepest part of the bag-shaped liquid chamber far from the liquid ink supply path, which not only complicates the structure of the head but also makes it difficult to operate at high speed. It is not suitable for continuous repeated use.

Moreover, with the technical content described in the above-mentioned publication, it is not possible to quickly prepare for the next liquid discharge after discharging the liquid using the generated heat, which is important in practice.

As described above, conventional methods have advantages and disadvantages in terms of structure, high-speed recording, multi-nozzle recording heads, generation of satellite dots, and fogging of recorded images, etc., and there are no applications that take advantage of these advantages. There was a restriction that it could only be applied. Further, the invention described in Japanese Patent Publication No. 58-49188 discloses that the time required for the temperature of the heat acting surface to reach the maximum temperature τP from the rising start temperature τi is τ0,
If the time required to attenuate from τP to (τρ-τi)/2 is τ1/2, then O When τ0≦10μS, τ0≦τ
1/2≦4τ0, when 10μs τ0, 10μs≦τ1
/2≦4τ0.

In other words, in a recording method in which droplets are ejected in a flying manner from the orifice of the recording head through the generation of bubbles due to thermal action and rapid state changes based on the rapid increase in volume and attenuation of the bubbles, the ability to repeatedly eject droplets is improved. In order to achieve this, it is necessary to improve the decay rate of the increased bubble volume.
By making the attenuation curve of the temperature waveform on the heat acting surface steeper,
It is possible to repeatedly improve the droplet ejection performance to a certain extent, but if it becomes steeper than a certain point, the meniscus of the liquid formed near the orifice will recede too much, causing air entrapment and unstable liquid replenishment. This results in a decrease in the fidelity and reliability of the response to the recorded signal.

Therefore, by adopting the waveform state of the temperature attenuation curve of the heat acting surface shown above, it is possible to repeatedly improve droplet ejection performance without causing the above-mentioned problems.

Furthermore, the invention described in Japanese Patent Application Laid-Open No. 55-123478 performs recording by discharging recording liquid from a discharge orifice by the action of thermal energy and flying it as a liquid drop. In order to improve the characteristics, it is required that the thermal energy generated by the heating resistor, which is the thermal energy generating means, be efficiently transmitted only to the recording liquid when the signal is applied at the rising edge, and that it quickly spread and fail at the falling edge. Therefore, an attempt is made to satisfy the above conditions by coating a thin film with low thermal conductivity on a substrate with good thermal conductivity, and further laminating a layer that generates thermal energy thereon.

In addition, the invention described in Japanese Patent Publication No. 58-49188 focuses on the temperature attenuation curve of the heat acting surface in order to improve the repeatable droplet ejection property, and shows the range of the attenuation curve. This is an extremely important condition in this method, which uses changes in the state of the liquid (ie, changes in the volume of bubbles) caused by the action of energy to eject and fly droplets from an orifice. However, when the recording head is actually operated continuously for a long time, the range is too wide, so it is not necessarily effective in improving the performance of repeatedly ejecting droplets. Furthermore, this merely describes the relationship between the rising curve and falling curve of the temporal change in the surface temperature of the heat acting surface, and does not specifically disclose technical means.

In addition, in the invention described in JP-A-55-123478, the thermal energy generating means is provided on a substrate on which a thin film with low thermal conductivity is formed, so that thermal responsiveness during high-speed recording is improved. It is said that the discharge stability, thermal energy efficiency, etc. are improved, and the load on the thermal energy generating means is reduced, resulting in improved durability. however. When the egg is moved at high speed for a long period of time, the surface temperature of the heating resistor cannot be completely attenuated, and the temperature at which the egg starts to rise increases with the sleeping time. In particular, when increasing the speed (repetitive drive frequency is higher than 4 KHz), the bubbles that have increased in volume do not completely disappear, and unnecessary bubbles remain, making it difficult to obtain stable droplet ejection. It disappears. Furthermore, since the surface temperature of the heating resistor increases, the life of the resistor is also shortened.

■11 Momme This invention was made in view of the above-mentioned circumstances,
The objective is to obtain stable repeated ejection performance when driven at high speed for a long period of time, and to obtain high image quality even when driven at high speed. Another object of the present invention is to provide a liquid jet recording device that prevents deterioration of the heat generating resistor due to heat accumulation even when the head is continuously driven for a long time, thereby improving the life of the head.

In order to achieve the above object, the present invention (1) accommodates the recording liquid introduced, generates bubbles in the recording liquid by heat, and reduces the acting force caused by the increase in the volume of the bubbles. a flow path provided with a thermal energy action section for generating heat; an orifice connected to the flow path for ejecting the recording liquid as droplets by the action force; In a liquid jet recording device comprising a liquid chamber for introducing the recording liquid and an introduction means for introducing the recording liquid into the liquid chamber, the side of the heating resistor that is not joined to the electrode is made of a highly thermally conductive member. (2) containing the recording liquid to be introduced and
A channel is provided with a thermal energy acting section that generates bubbles in the recording liquid using heat and generates an acting force as the volume of the bubbles increases; A liquid jet recording device comprising an orifice for ejecting droplets, a liquid chamber for communicating with the flow path and introducing the recording liquid into the flow path, and an introduction means for introducing the recording liquid into the liquid chamber. The heating resistor is characterized in that the sides of the heating resistor are surrounded by electrodes. The present invention will be explained below based on examples. First, the principle of ink jetting by a bubble jet will be explained based on FIG. 6. (a) is a steady state, in which the surface tension of the ink 30 and the external pressure are in equilibrium on the orifice surface.

In (b), the heater 29 is heated until the surface temperature of the heater 29 rises rapidly and a boiling phenomenon occurs in the adjacent ink layer, and microbubbles 31 are scattered.

In (c), the adjacent ink layer is rapidly heated on the entire surface of the heater 29 and instantly vaporizes. Boiling! Create an I film and fill this bubble 3
1 is in a grown state. At this time, the pressure inside the nozzle is
The bubbles rise as much as they grow, and the balance with the external pressure on the orifice surface is lost, causing an ink column to begin to grow from the orifice.

(d) shows a state in which the bubble has grown to its maximum, and ink 30 corresponding to the volume of the bubble is pushed out from the orifice surface. At this time, no current is flowing through the heater 29, and the surface temperature of the heater 29 is decreasing. The maximum value of the volume of the bubble 31 is slightly delayed from the timing of electric pulse application. (e) shows a state in which the bubbles 31 are cooled by ink or the like and begin to contract. At the tip of the ink column, it moves forward while maintaining the extruded speed, and at the rear end, as the bubbles contract, the nozzle internal pressure decreases, causing the ink to flow back from the li-orifice surface into the nozzle, creating a constriction in the ink column. ing.

In (f), the air bubbles 31 are further contracted, the ink comes into contact with the heater surface, and the heater surface is cooled even more rapidly. At the orifice surface, the external pressure is higher than the nozzle internal pressure, so the meniscus is largely moving into the nozzle. The tip of the ink column becomes a droplet and moves 5 to 1 liters toward the recording paper.
It is flying at a speed of om/see.

In (g), the air bubbles have completely disappeared in the process of refilling the orifice with ink by capillary action and returning to the state of (a). 32 is a flying ink droplet. FIG. 7 is a perspective view of the bubble jet recording head, and FIG. 8 is an exploded configuration diagram of the recording head, in which (a) shows the lid substrate, (b)
) is a diagram showing the heating element substrate, and FIG. 9 is a back view of the lid substrate shown in FIG. 8 (.). In the figure, 21 is a lid substrate, 22
2 is a heating element substrate, 23 is a recording liquid inlet, 24 is an orifice, 25 is a channel, 26 is a region for forming a liquid chamber, 2
7 is an individual (independent) electrode, 28 is a common electrode, and 29 is a heating element (heater).

FIG. 10 is a partial view of the bubble jet liquid jet recording head, in which (a) is a front partial view seen from the orifice side;
b) is a partial view cut along the dashed line XX in (.).

The recording head 41 shown in these figures has a predetermined number of grooves of a predetermined width and depth at a predetermined linear density on a substrate 43 on which an electrothermal transducer 42 is provided. By bonding the grooved plate 44 so as to cover the substrate 43, it has a structure in which a liquid discharge part 46 including an orifice 45 for ejecting liquid is formed.

The liquid discharge part 46 is a heat acting part where the thermal energy generated by the orifice 45 and the electrothermal converter 42 acts on the liquid to generate bubbles, causing rapid deterioration in the condition due to expansion and contraction of the volume. 47. The heat acting part 47 is located above the heat generating part 48 of the electrothermal converter 42, and has a heat acting surface 49, which is a surface of the heat generating part 48 that comes into contact with the liquid, as its bottom surface. The heat generating section 48 is
Lower part N50 provided on the base body 43. It is composed of a heating resistance layer 51 provided on the lower part M50 and an upper layer 52 provided on the heating resistance layer 51.

The heating resistance layer 51 includes the WJ 51 to generate heat.
Electrodes 53 and 54 for energizing are provided on the surface thereof, and a heat generating portion 48 is formed by a heat generating resistive layer between these electrodes.

The electrode 53 is an electrode common to the heat generating section of each liquid discharging section, and the electrode 54 is a selection electrode for selectively generating heat in the heat generating section of each liquid discharging section. It is provided along the flow path.

The upper layer 52 isolates the heat generating resistor layer 51 from the liquid in the liquid discharge part 46 in order to chemically and physically protect the heat generating resistor layer 51 from the liquid used, and also provides a connection between the electrodes 53 and 54 through the liquid. It has the protective function of the heating resistance layer 51 to prevent short circuits.

The upper layer 52 has the above-mentioned functions, but
If the heat generating resistor layer 51 is liquid resistant and there is no need for an electrical short circuit between the electrodes 53 and 54 through the liquid, it is not necessarily necessary to provide it, and the surface of the heat generating resistor layer 51 may immediately come into contact with the liquid. It may be designed as an oval electrothermal converter.

The lower layer 50 has a heat flow control function, that is, when ejecting droplets, the heat generated by the heating resistor M51 is transferred to the substrate 43.
The proportion of conduction toward the heat-effecting portion 47 side is increased as much as possible than the conduction toward the side, and after the droplet is ejected, that is, after the electricity to the heat-generating resistor layer 51 is turned off, the heat-effecting portion 4
7 and the heat generating part 48 is quickly released to the substrate 43 side, and the liquid in the heat acting part 47 and the generated bubbles are rapidly cooled.

Useful materials for forming the heating resistor 51 include, for example, tantalum-Sin2 mixture, tantalum nitride, nichrome, silver-palladium alloy, silicon semiconductor,
Or hafnium, lanthanum, dinoreconium, titanium, tantalum, tungsten, molybdenum, niobium. Examples include borides of metals such as chromium and vanadium.

Among the materials forming the heating resistor 51, metal borides are particularly excellent, and among them, hafnium boride has the best characteristics.
This is followed by zirconium boride, lanthanum boride, tantalum boride, vanadium boride, and niobium boride.

The heating resistor 51 can be formed using the above-mentioned materials using techniques such as beam evaporation and sputtering. The film thickness of the heating resistor 51 is determined according to its area, material, shape and size of the heat-acting part, and actual power consumption, etc. so that the amount of heat generated per unit time is as desired. However, in normal cases, o. o
ot to 5 μm, preferably 0.01 to 1 μm.

As the material constituting the electrodes 53 and 54, many commonly used electrode materials can be effectively used, including AQ, Ag, Au, Pt, Cu, etc. It is provided at a predetermined location with a predetermined size, shape, and thickness using a method such as vapor deposition.

The characteristics required of the protective layer 52 are to protect the heat generating resistor 51 from the recording liquid without preventing the heat generated by the heat generating resistor 51 from being effectively transferred to the recording liquid. Examples of useful materials for forming the protective layer 52 include silicon oxide, silicon nitride, magnesium oxide, aluminum oxide, tantalum oxide, and zirconium oxide, which can be prepared using methods such as electron beam evaporation and sputtering. It can be formed by The thickness of the protective layer 52 is usually 0.01 to 10 μm, preferably 0.1 to 5 μm, and most preferably 0.1 to 3 μm.

In order to achieve the above object, the present invention provides an orifice 45
After the droplets are ejected from the heating resistor layer 51, that is, after the power to the heat generating resistor layer 51 is turned off, the heat acting section 47 and the heat generating section 4
Focusing on the fact that the heat in the area 8 must be efficiently dissipated and the liquid in the heat effecting part 47 and the bubbles generated must be quickly cooled, in the thermal energy effecting surface 49, the side to which the electrode is not bonded. is characterized by being surrounded by a highly thermally conductive member.

Generally, when electricity is applied through an electrode to a heating resistor, the surface temperature of the heating resistor rises rapidly and the adjacent ink layer is heated, causing bubbles to grow, as explained in FIG. Thereafter, when the electricity is turned off, the bubbles begin to contract after reaching the maximum value. At this time, in the heating resistor (heater) 29 as shown in FIG. 8, heat is efficiently radiated from the surface of the heating resistor in the direction where it is joined to the electrodes 27 and 28, but in other directions. Heat is radiated less efficiently towards the electrode than towards the electrode. For this reason, the contraction of the bubble is as shown in Figure 11 (the shaded area indicates the bubble).
Rather than uniformly contracting on the surface of the heating resistor, the shape is collapsed in the direction of the electrode.

Therefore, defects such as cracks are likely to occur on the surface of the heating resistor when the head is moved north for a long period of time, significantly reducing the durability of the head.

In order to solve the above-mentioned drawbacks, the present invention provides efficient heat dissipation even when the head is driven once at 5 high speeds by surrounding the sides of the heating resistor to which the electrodes are not bonded with a highly thermally conductive material. Bubbles grown on the surface of the resistor can be uniformly deflated.

1(a) to (e) are for explaining a method of forming a heater board used in a liquid jet recording apparatus according to the present invention. In the figures, 1 is a substrate, 2 is a heating resistor, and 3 is a heat sink. , 4 is a common electrode, 5 is a selection electrode, and 6 is an insulating layer. A heat sink of A2 is patterned on the side of the heating resistor 2. First, as shown in (a), a substrate 1 with a SiO film formed on the surface by sputtering is prepared.
A heating resistor 2 is patterned on top to a desired size.

Next, as shown in (b), the insulating layer 6, the common electrode 4, and the selection electrode 5 are patterned so as to surround the sides of the heating resistor 2. Furthermore, as shown in (C), the AQ heat sink 3 may be patterned so as not to come into contact with the heating resistor 2 and the electrodes 4 and 5. FIG. 1(d) shows a cross-sectional view taken along line XX of (Q), and FIG. 1(e) shows a cross-sectional view taken along line Y-Y of (Q).

2(a) to 2(f) and (g) show that an AQ heat sink is patterned on the bottom and side surfaces of the heating resistor 2. FIG. First, as shown in (a), the heat sink 3 is deposited on the entire surface of the substrate 1. Next, the insulating layer 6 is patterned as shown in (b), and the heating resistor 2 is patterned thereon to a desired size as shown in (c). Furthermore, electrode 4
, 5 may be patterned as shown in (d) so that they do not come into contact with the heat sink 3. Figure 2 (e) is the X in (d)
-X sectional view, (f) shows a YY sectional view of (d). In this case, in order to prevent the adhesion from decreasing due to thermal expansion of the heat sink, the heat sink may be patterned into a slit shape as shown in (g) in the step (a).

In addition, in the example shown in FIGS. 1 and 2, the heat sink is
Although Q was used, it is not necessarily limited to AQ, and gold,
Any highly thermally conductive material such as silver, copper, zinc, tungsten, etc. can be used.

Furthermore, the thinner the insulating layer is, the better the heat dissipation effect, as long as the insulation properties are not impaired. Figures 3(a) to 3(d) show a method of surrounding the sides of the heating resistor with selective electrodes. In (a), a heating resistor 2 of a desired size is patterned on a substrate 1.

Next, in (b), the selection electrode 5 is patterned to surround the sides of the heating resistor 2, and in (c) and (d), the insulating layer 6 is patterned.
Pattern the common electrode 4 by sandwiching it. Figure 3 (e
) is a sectional view taken along line XX in (d).

FIG. 4 shows a method of surrounding the sides of the heating resistor with common electrodes. A selection electrode 5 is patterned on the substrate 1 as shown in FIG. 4(.). Next, the heating resistor 2 is patterned as shown in (.) with the insulating layer 6 shown in (b) in between. An opening 7 is provided in the insulating layer 6 at a location corresponding to the selection electrode 5, and is connected to the heating resistor 2. Furthermore (d)
The common electrode 4 is patterned as shown in FIG.

FIG. 4(8) is a sectional view taken along line XX in FIG. 4(d).

Further, the shapes of the heating resistor 2 and the accompanying common electrode 4 and selection electrode 5 shown in FIGS. 1 to 4 are not limited to rectangular or circular shapes, but can be freely changed as necessary. Furthermore, a protective layer for protecting the heating resistor 2 and a resin layer (not shown) for protecting the electrodes are usually provided.

Note that the shaded portions in FIGS. 1 to 4 indicate the portions patterned in each step.

Further, as shown in FIGS. 5(a) to 5(d), a recording head can be manufactured using a photosensitive dry film in the following manner. In the figure, 61 is a substrate, 62 is a heating resistor, 6
3 is a protective film, 64 is a photosensitive dry film, 65 is a top plate, 66 is an adhesive layer, and 67 is an ink chamber.

A photosensitive dry film 64 is laminated on a heater board (substrate) 61, a mask patterned to obtain the desired flow path and ink chamber is layered, and light is exposed from above (Fig. 5 a, b). . Photosensitive dry film 6
4, the exposed portion undergoes a photopolymerization reaction and is cured. Therefore, when development is performed after exposure, the unexposed portions are dissolved and removed, forming channel walls 64p (FIG. 5C). In addition, AQ as a sink
When setting up etc. AQ has poor chemical resistance and is easily corroded by alkaline solutions such as inkjet inks, so it must be covered with a dry film pattern to prevent it from coming into direct contact with the ink.
Alternatively, it is better to provide a resin layer on the part that comes into contact with the ink, similar to the electrode, to prevent the heat sink from coming into contact with the ink. Next, glue N to the glass top plate 65.
Join via 6G. This glass top plate 65 is drilled in a portion corresponding to the ink chamber 67, and the ink chamber 67 is
7. A supply port for supplying ink has been machined (Fig. 5d). Further, when forming the walls of the ink chamber and the flow path, instead of laminating the photosensitive dry film on the nozzle substrate side as described above, it can also be formed by laminating it on the glass top plate side. Alternatively, desired ink chambers and channels can be formed by directly etching the glass top plate.

When photosensitive glass is used for the top plate, when the photosensitive glass is exposed to light in the pattern of the desired ink chamber flow path, only the exposed areas become opalescent. This opalescent glass portion may be etched with dilute hydrofluoric acid. The top plate is not limited to the glass mentioned above, but may also be made of ceramic, resin, or metal, but in order to connect it to the heater board, the top plate should have adhesive properties. It is preferable to use ltMJ or have adhesive properties on the top plate itself.

The present inventors manufactured the heater board shown in FIG. 4 as follows. First, Si○2 was deposited on the Si substrate as a lower layer.
After spuntalinting to a thickness of 5 μm, photolithography, etching, and sputtering techniques were used to sequentially form AQ to a thickness of 5,000 μm as a selective electrode and SiO2 to a thickness of 1.2 μm as an insulating layer into the desired shape. I patterned it on. Next, as a heating resistor, Ta-SiO2 was patterned into a circular shape with a thickness of 400 mm and a diameter of 40 μm (the pitch of the heating resistor was 62 μm). Next, pattern AQ into a desired shape with a thickness of 5,000 mm as a common electrode, and apply a resin layer on the area where AQ is laminated. A heater board was formed by patterning.

Next, an ejection port was formed through the process described in FIG. 6 (the thickness of the photosensitive dry film was 25 μm).

Using the head manufactured as described above, a drive frequency of 4
．． When continuously operated at 1K I-{z, the number of stable droplets ejected was improved from about 10' times conventionally to about 109 times.

As is clear from the above description, the present invention has the following effects.

(1) Effects Corresponding to Claim 1 (1) Since the structure is simple, it can be manufactured at low cost using conventional heater board forming techniques, such as sputtering, photolithography, etching, etc.

(2) Since the heat dissipation of the heating resistor is performed efficiently, it is possible to operate at a higher speed (for example, higher than 4 KHz).

(2) Since the thermal load on the heating resistor is reduced, the durability of the head can be improved.

(2) Since the bubbles grown on the surface of the heating resistor contract uniformly, defects such as cracks are less likely to occur, and the durability of the head can be improved.

(2) Since the structure is a laminated structure, it does not take up much space and is advantageous when the nozzle density is increased (for example, the density is higher than 16 nozzles/mm).

■You can freely change the shape of the heating resistor and make it accordingly.

(2) Effects Corresponding to Claim 2 In addition to the above-mentioned items (1) to (2), since it can be made using the same mask, the same material, and the same process as the electrodes, it can be manufactured at a lower cost.

Furthermore, since the electrode also serves as a heat sink, space can be saved, which is more effective when increasing the density of nozzles.

[Brief explanation of the drawing]

FIGS. 1(a) to (e) are diagrams for explaining a method of forming a heater board used in a liquid jet recording apparatus according to the present invention, and FIGS. Figures 3 (a) to (8) are diagrams for patterning a heat sink on the bottom and side surfaces of a resistor, and Figure 4 ( a) ~ (8
) is a diagram for explaining the method of surrounding the sides of the heating resistor with a common electrode, Figure 5 is a diagram for explaining the manufacturing process of the recording head, and Figure 6 is a diagram for explaining the bubble jet ink discharge of the head. 7 is a perspective view of the recording head, and FIG. 8 is an exploded configuration diagram of the recording head.
) shows the lid substrate, (b) shows the heating element substrate, and FIG.
10 is a partial view of the recording head; (a) is a front partial view as seen from the orifice side of the head; (b) is a section taken along the X-X line of (a). Figure, 1st
FIG. 1 is a diagram showing a state in which bubbles are contracted. DESCRIPTION OF SYMBOLS 1... Planting board, 2... Heating resistor, 3... Heat sink, 4... Common electrode, 5... Selection electrode, 6...
Insulating layer. (e) Figure 6 ( d冫#== Figure Figure ◇ (C) (d) Figure Figure

Claims (1)

[Claims] 1. A flow path that accommodates the recording liquid introduced and is provided with a thermal energy acting section that generates bubbles in the recording liquid by heat and generates an acting force as the volume of the bubbles increases. an orifice that communicates with the flow path and causes the recording liquid to be ejected as droplets by the acting force; and a liquid chamber that communicates with the flow path and introduces the recording liquid into the flow path. A liquid jet recording device comprising an introduction means for introducing recording liquid into the liquid chamber, characterized in that a side of the heating resistor that is not joined to the electrode is surrounded by a highly thermally conductive member. Recording device. 2. A flow channel that accommodates the recording liquid to be introduced and is provided with a thermal energy acting section that generates bubbles in the recording liquid by heat and generates an acting force as the volume of the bubbles increases; an orifice in communication with which the recording liquid is ejected as a droplet by the acting force; a liquid chamber in communication with the flow path and with which the recording liquid is introduced into the flow path; and a recording liquid in the liquid chamber. What is claimed is: 1. A liquid jet recording device comprising an introduction means for introducing a heat generating resistor, characterized in that the sides of a heating resistor are surrounded by electrodes.