JPH054347A - Manufacturing method for liquid-jet recording head, liquid-jet recording head manufactured by the same method, and liquid-jet recording device equipped with the same head - Google Patents

Abstract

PURPOSE:To provide a method for manufacturing a liquid-jet recording head, wherein an aging process is carried out under optimum conditions to obtain a heating resistor having a consistent resistance for a long period of time, thereby providing a good and stable delivery of recording liquid. CONSTITUTION:Circuits 200, 400 for optimizing electric signals which are applied to a heating resistor 23 as an aging process and a circuit 500 for controlling the temperature of a substrate at an optimum temperature during the aging process are provided on a head substrate 1A and a heat aging process is carried out in or after the manufacture of a recording head 1 using these circuits.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a liquid jet recording head, a liquid jet recording head manufactured by the method, and a liquid jet recording apparatus equipped with the liquid jet recording head.

[0002]

2. Description of the Related Art A liquid jet recording method is one in which flying droplets are formed by a recording liquid such as ink, and the droplets are adhered to a recording material such as paper to perform recording. The liquid jet recording apparatus is capable of high-speed printing and high-density recording with low noise, and does not require processing such as development and fixing on plain paper, so that the apparatus itself can be downsized. At the same time, it is attracting particular attention because it has good productivity in mass production and can be manufactured at low cost.

Particularly, the on-demand type liquid jet recording apparatus is
Does not require a high-voltage generator or a device for collecting unnecessary ink, which is required in a continuous type liquid jet recording device,
Since the device can be miniaturized, its application is expected to be promising. Among them, the one described in Japanese Patent Publication No. 61-59914 discloses heating the liquid in a liquid passage filled with the liquid to give a pressure displacement to the liquid due to an abrupt volume increase due to foaming. As a liquid jet recording apparatus, a liquid jet recording head is used which discharges liquid from a discharge port communicating with a path to form flying droplets, and causes such droplets to adhere to a recording material for recording. It has been especially noticed.
Moreover, the above-described liquid jet recording head has a feature that the density of nozzles and the number of nozzles can be easily increased. Therefore, by increasing the length of the head, it is possible to improve the printing speed and obtain a high-quality image. There is a feature.

In the liquid jet recording head which uses thermal energy to form the flying droplets, the means for heating the recording liquid can generate heat by applying an electric signal to heat the recording liquid. The electrothermal converter includes a heating resistor (hereinafter referred to as a heater) and a pair of electrodes for applying an electric signal to the heating resistor. The recording liquid used here is generally composed of a recording component such as a pigment or a dye and water for dissolving or dispersing the recording component, or a solvent component composed of water and a water-soluble organic solvent.

By the way, the heating limit temperature for rapid vaporization in such an aqueous recording liquid, that is, the heat conduction through the extremely thin and stable vapor film between the heater surface and the liquid. The temperature at which steam is generated due to the amount of heat transferred in is 250 ° C to 350 ° C. Therefore, when a recording liquid having such a temperature characteristic is used, an electric signal is applied to the heater to foam the recording liquid to form flying droplets for recording on the recording material. 300 ℃ from ambient temperature
It will be repeatedly heated at temperatures up to ~ 800 ° C.

The heater, electrodes, etc. are formed by a semiconductor process, and for example, heating resistors (eg, HfB ₂ , ZrB ₂ , TaN ₂ ) provided on the substrate (eg, Si, glass, ceramics, etc.) are provided. , TaS
on the heat resistant resistance material such as i), an intermediate layer (for example, Ti, Cr)
Etc.), a wiring portion (electrode, eg, Al, Au, Ag, Cu, etc.) made of a metal that is a good electric conductor is laminated so that the intermediate layer is exposed, and the exposed portion is a heater. Becomes Further, a protective film having excellent heat resistance and excellent recording liquid blocking property for preventing electrolytic corrosion and oxidation from the recording liquid is formed on the heater and the electrode as required.

As described above, in a recording head having a structure in which a heater is repeatedly heated to a high temperature by an electric signal according to a recording signal to heat a recording liquid to eject droplets, and a recording apparatus equipped with the recording head. For the purpose of improving recording characteristics (especially characteristics of recording liquid, for example, viscosity, surface tension, density, etc.) at the time of recording, in the state where a liquid jet recording head is mounted on a recording apparatus, there is, for example, US Pat.
No. 47122172, pre-ejection treatment, or USP No. 4,463,359, USP No. 4,296,421.
No., USP No. 4719472, and USP No. 471.
It was performed in the recording mode including the preheating treatment shown in No. 2172.

By the way, when such a treatment is carried out, the characteristics of the recording liquid at the time of recording are improved, but it can be said that it is sufficient to obtain the best recording state from the initial stage. However, the resistance value change of the heater material is caused by the phase change, stress change, oxidation, and composition change of the heater material due to the repeated high temperature heat generation of the heater in the recording mode including the above-mentioned preliminary discharge processing and preliminary heating processing. Cause In addition, the interface resistance in the boundary region between the heater material and the wiring portion (electrode), and the change in the resistance distribution of the heater material due to the diffusion phenomenon between the two occur.

In order to solve these problems, a conventional method for manufacturing a liquid jet recording head disclosed in, for example, Japanese Unexamined Patent Publication (Kokai) No. 2-78554, that is, by heating a heater and heating the heater, the heater material is heated. The electric signal is applied enough from the electrodes to stabilize the resistance value of
Manufacturing methods have been practiced that include an aging step of heat treating the heater material. By adopting such a manufacturing method, it becomes possible to prevent deterioration of the quality of the recorded image and deterioration of the durability of the heater material due to changes in the heater resistance value, and even in the case of recording for a long time. A liquid jet recording head has been provided that can always obtain a stable and stable droplet discharge state.

[0010]

However, in the above-mentioned conventional example, when manufacturing the liquid jet recording head,
Since a plurality of substrates are first formed in a chip shape on a wafer by a semiconductor process, the larger the wafer becomes, or the smaller the number of chips becomes and the larger the number becomes, the more uneven the film distribution on the wafer due to film formation becomes, or Due to the variation in the film thickness between the liquid jet recording heads manufactured, the film thickness of the heater material and the like varies. Further, in the conventional aging process in the manufacturing process, the difference in the optimum condition of aging due to the difference in the film thickness of the heater material or the like in each liquid jet recording head is ignored. However, it was not a sufficient solution to the deterioration of printing quality and deterioration of heater material durability.

In view of these problems, an object of the present invention is to
When performing recording, the heater resistance change is suppressed within a suitable range so that a good droplet discharge state can always be obtained from the initial stage of recording, and particularly good and stable droplets are maintained even during recording for a long time. It is an object of the present invention to provide a method of manufacturing a liquid jet recording head that can obtain a discharge state and that has less characteristic variation between the liquid jet recording heads.

A second object of the present invention is to provide a method of manufacturing a liquid jet recording head which is highly durable against repeated heating in a heater for a long period of time.

A third object of the present invention is to provide a method of manufacturing a liquid jet recording head which can suppress manufacturing variations, can obtain good and stable droplet discharge, and can be manufactured at low cost and easily. .

A fourth object of the present invention is to suppress the change in heater resistance value within a suitable range so that a good droplet discharge state can always be obtained, and it is always good and stable even in recording for a long time. It is an object of the present invention to provide a liquid jet recording head that can obtain the above droplet discharge state.

A fifth object of the present invention is to provide a liquid jet recording head having a high durability and a high yield, at a low cost, against repeated heating in a heater for a long period of time.

A sixth object of the present invention is to provide a low-priced liquid jet recording head capable of suppressing variations in manufacturing and obtaining good and stable droplet ejection.

A seventh object of the present invention is to provide a liquid jet recording apparatus equipped with a liquid jet recording head having excellent characteristics as described above at low cost.

[0018]

In order to achieve such an object, a method of manufacturing a liquid jet recording head according to the present invention comprises:
A liquid jet recording head having an electrothermal converter on a substrate, the electrothermal converter including a heating resistor that generates thermal energy used to eject a recording liquid, and an electrode for applying an electric signal to the heating resistor. In the manufacturing process, an aging process of the heating resistor is performed by applying an electric signal sufficient for stabilizing the resistance value of the heating resistor to the heating resistor via the electrode, and performing heat treatment by the heat generation. In order to optimize the aging condition, a control means for optimizing the aging condition is integrated into a circuit and provided on the substrate of the liquid jet recording head, and the aging process is performed through the integrated circuit. It is characterized by performing.

Further, according to this manufacturing method, it is possible to obtain the liquid jet recording head and the liquid jet recording apparatus equipped with the liquid jet recording head, which can achieve the above-mentioned object.

In the manufacturing method according to the present invention, the optimum electric signal used for the aging treatment is sufficient to cause the heat generating resistor to generate heat and stabilize the resistance of the heat generating resistor in the heating process due to the heat generation. If it is one, when recording the image,
The above object can be achieved even if the signal is different from the signal applied during the preliminary ejection process or the preliminary heating process.

Further, the liquid jet recording apparatus of the present invention can have means for optimizing the ejection of ink from the recording head.

[0022]

According to the present invention, an electric signal is supplied to the heating resistor to generate heat, and the aging process performed in the heating process is performed by first setting based on the change in the resistance value of the heating resistor. In addition to using the optimum electric signal described above, the electric signal is used to control the substrate so as to keep it at the optimum set temperature. It is possible to maintain a durable ejection function.

[0023]

Embodiments of the present invention will be described in detail and specifically below with reference to the drawings.

FIG. 1 shows an example of a liquid jet recording apparatus equipped with a liquid jet recording head manufactured by the method of the present invention, and FIG. 2 shows the structure of the main part of the liquid jet recording head shown in FIG. 3 shows an example of the head substrate of the liquid jet recording head shown in FIG. 2, and FIG. 4 shows an example of the arrangement of the head substrate as shown in FIG. 3 on a wafer.

In FIG. 1, 1 is a liquid jet recording head,
2 is equipped with a recording head 1 and a sub ink tank 3,
A carriage 5 that reciprocates along the guide shaft 4 is a platen that holds a recording material (recording sheet) 6 at a position facing the recording head 1. The sub tank 3 is supplied with the recording liquid from a main tank 7 for storing the recording liquid by a supply tube 8 and is further led from here to a liquid chamber 10 (see FIG. 2) of the recording head 1 via a supply pipe unit 9. . In addition,
In the above-mentioned configuration, the recording head 1, the sub-ink tank 3, the main tank 7, the supply tube 8, and the supply pipe unit 9 are integrated into one unit or a recording having all the above-mentioned functions. The head may be used. 11 is a flexible printed wiring board (hereinafter referred to as FPC).
Various control signals including a discharge signal from the discharge signal generation unit 12, the preliminary discharge process control unit 13, the preliminary heating process control unit 14, and the like of the recording apparatus 11 are recorded by the recording head 1.
Is supplied to. Reference numeral 15 is a pressing member that holds the end portions of the supply pipe unit 9 and the FPC 11, and the recording head 1 and the like with the base plate 16.

On the other hand, with respect to the recording head 1 for recording, the recovery pump 17, the cap member 18 and the space between them are contacted with the recording head 1 in the vicinity of the home position outside the recording area to perform the ejection recovery operation and the capping process. A suction tube 19 for communication is provided and controlled by the recovery processing control means 20. Thus, in combination with the control of the recording head 1 side by the preliminary ejection processing control means 13 and the preliminary heating processing control means 14, in order to obtain high-quality recording, corresponding operations are performed independently or in a series of modes. .

Next, the structure of the recording head 1 will be described with reference to FIG. Here, 1A is a head substrate, and on the head substrate 1A, a common liquid chamber 10, a liquid passage 21 communicating therewith, an ejection port 22 for ejecting a recording liquid (hereinafter referred to as ink), and each liquid passage 21 are provided. Heater 23 provided
Are provided respectively, and the recording head 1 is constructed by stacking a top plate 24 on top of each. FIG. 3 shows an electrothermal converter as a liquid heating means formed on the head substrate 1A by a semiconductor process, that is, a heater 23 and a selection electrode 23A and a common electrode 23B which supply an electric signal for heating the heater 23. Shows the formation state of.

Further, here, 25 is a heating resistor used for knowing a change in the resistance value of the heater 23, which is necessary in the aging treatment process described later, and 25A and 25B are its electrodes and the heating resistor 25. The shape and size, the material, the film thickness, etc. are the same as those of the heater 23. Furthermore, 26 is a substrate temperature control means for the head substrate 1A,
26A and 26B are electrodes thereof, and 27 is a substrate temperature detecting means for detecting the substrate temperature of the substrate 1A. Then, the electrodes 25A and 25B of the heating resistor 25,
The electrodes 26A and 26B of the substrate temperature control means 26 and the substrate temperature detection means 27 are all connected to the integrated circuit 28 on the substrate 1A, and the integrated circuit 2 is subjected to the aging process.
Signals are exchanged between the outside and these via the unit 8. Further, 29 is a connection terminal to the integrated circuit 28, and is connected from this connection terminal 29 to a heating signal generating means for applying to the heater 23 (not shown) via the FPC 8 shown in FIG.

The functions of the above-mentioned individual functions will be described below.

When the instruction signal for the aging process enters the heating signal generating means (not shown), the resistance value of the heating resistor 25 is changed by the signal generated from the heating signal generating means (at this time, the heater 23 is changed). Is not applied the signal from the heating signal generating means). This change in resistance value is caused by the integrated circuit 28.
After being detected as a value by, the heating signal for aging processing is determined based on the value and sent back to the heating signal generating means (or, the resistance change detection value is sent back to the heating signal generating means as it is. The heating signal generation means may determine the heating signal for the aging process based on the resistance change detection value). The determined aging processing signal is stored in the heating signal generating means and is used when the aging processing occurs again. The substrate temperature control means 26 and the substrate temperature detection means 27 are controlled by the integrated circuit 28 to a preset temperature value of the substrate 1A at the time of the aging processing after the aging processing signal is determined. When the temperature value of the substrate 1A reaches the temperature during the aging process, the determined aging process signal is applied to the heater 23 for a preset time.

When the above aging process is completed,
The heating signal applied to the heater 23 is switched from the aging processing signal to the normally used heating signal. Further, the substrate temperature control means 26 and the substrate temperature detection means 27 are
It is used as needed even after the aging process is completed.

FIG. 4 is a schematic view showing a state where the substrate 1A formed on the wafer 30 as described above is in a state before being cut out.

In order to perform recording using the recording apparatus having the above-described structure, first, ink is supplied from the main tank 7 to the sub tank 2, the liquid chamber 10 and the liquid passage 21 through the supply tube 8 and the supply pipe unit 9. To fill. Then F
An electric signal, that is, an electric signal from the ejection signal generating means 12 is applied to the heater 23 of the recording head 1 by the PC 11. This causes the heater 23 to generate heat, so that thermal energy is applied to the ink existing in the liquid passage 21 near the heater 23. Thus, when heat energy is applied to the ink from the heater 23, air bubbles accompanied by an instantaneous increase in the volume of the ink are generated in that portion, and the ink existing on the downstream side (the ejection port 22 side) of the heater 23 is discharged. The ink is ejected from the outlet 22 to form a flying ink droplet. Then, the ink droplets are attached to a recording material such as paper at a facing position to record a desired image. At the time of recording, preliminary ejection processing, preliminary heating processing, and recording head recovery processing are performed for the purpose of optimizing ink ejection from the recording head 1 and forming a high-quality image. These processes are controlled by the preliminary ejection process control unit 13, the preliminary heating process unit 14, and the like.

The preliminary discharge process and the preliminary heating process are
It mainly adjusts the viscosity of the ink. In the recovery process, the ink in the recording head 1 is pressed or sucked while the recording head 1 is in contact with the cap member 18 to recover the clogging of the ejection port 22.

In the method of manufacturing the liquid jet recording head of the present invention, an electric signal is applied to the heater 23 at any stage of manufacturing the liquid jet recording head mounted on the apparatus having the above-mentioned structure. An aging treatment process for stabilizing the resistance value of the heater 23 to a re-optimal value by heating only the vicinity of the heater 23 is incorporated.

That is, the aging treatment process related to the heat treatment is a process for forming the liquid jet recording head, and the electrothermal energy conversion including the heater 23 and the electrodes 23A and 23B for applying an electric signal to the heater 23 is performed. It can be incorporated during the manufacturing process of a series of liquid jet recording heads after the body is formed. Alternatively,
It is also possible to perform the heating process for the recording head 1 after the ejection recording head is completed and before it is mounted on the recording device, or before the recording head 1 is mounted on the recording device and a state where normal recording is performed ( For example, it is possible to perform the heat treatment including the aging described above before the recording device is sold.

However, considering that the heat treatment is easy, the heat treatment is preferably performed after the recording head is completed. In particular, in terms of being able to apply an electric signal to a plurality of recording heads at a time, it is preferable to perform this on the completed recording head 1 before mounting it on the recording apparatus. It is necessary to prepare a separate device for heat treatment so that an electric signal can be given thereto.

On the other hand, when heat treatment is performed with the recording head mounted in the recording apparatus, a separate heat treatment apparatus is not required. It should be noted that when the recording head 1 is mounted on the recording apparatus, the recording head 1 can be filled with ink. It is better to fill the ink with ink and heat it between the ink and the heating resistor 23. Since the wettability between the ink and the liquid passage 21 is improved and more stable ink ejection can be performed, after the assembly of the recording apparatus is completed, the recording head 1 is filled with the ink,
It is also preferable to carry out the heat treatment including the above-mentioned aging after the ejection is possible.

Furthermore, in the example of the heat treatment described above, even if the heat treatment is performed before the recording head 1 is attached to the recording apparatus as in the former case, the recording head 1 can be filled with ink. The same effect as the latter heat treatment can be obtained. On the other hand, it is not always necessary to fill the recording head 1 with ink in the latter heat treatment. The steps other than the formation of the heat treatment circuit provided on the substrate and the heat treatment of the heater described above in the method of manufacturing a liquid jet recording head of the present invention are the same as those of the conventional liquid jet recording head and a liquid mounting the same. This is the same as the method for manufacturing the jet recording apparatus, and detailed description thereof will be omitted.

The heater heat treatment signal applied in the manufacturing method of the present invention is, for example, a signal in which the heat energy generated by the heater 23 when applied is larger than the electric signal applied for ejection. And, and
It is preferable to apply an electric signal that can heat the heater 23 to a temperature at which the resistance change due to the heat history of the heater 23 due to the applied electric signal falls within a range in which stable ejection can be maintained. It should be noted that such a heater heating processing signal can be applied through the FPC 11 from a heating signal generating means (not shown) provided outside.

Further, it is possible to use a high frequency signal or a direct current as such a heater heating processing signal. In the case of a high frequency signal, the applied voltage, applied pulse width,
A desired heat treatment can be performed by changing the number of applied pulses, the frequency, or the like individually or in combination. When a direct current is applied, a desired heat treatment can be obtained by controlling the current value and the application time.

The heat treatment time for heating the heater 23 as described above by applying the heating electric signal is applied under the condition that the time is as short as possible within the range in which the above-mentioned effect is obtained. It is preferable. This is the heater 23 by performing the treatment in a short heating time.
Also, it is possible to extend the life of these components by minimizing the influence of heat that causes deterioration and the like on the components that make up the heater and around the heater, and to suppress the diffusion of heat to the periphery of the heater. This is because the quality reliability of the jet recording head and the liquid jet recording apparatus can be improved.

The heat treatment according to the present invention, that is, the applied voltage, the applied pulse width, the applied pulse number of the high frequency signal to be applied, or the direct current is changed to obtain a value that optimizes the aging condition. The heat treatment is carried out under the optimum aging condition, and an experiment conducted to specifically find a method for manufacturing such a liquid jet recording head will be described below.

In the following specific experimental example, the ink ejection direction as shown in FIG.
A case will be described where the present invention is applied to a liquid jet recording head in a form in which the ink supply direction to the liquid path 21 provided with is substantially parallel to the above. However, the present invention is not limited to this.
The present invention can also be applied to a liquid jet recording head in which two directions are different from each other, for example, the directions are orthogonal to each other.

FIG. 5 shows the structure of the control means for optimizing the aging conditions according to the present invention. As described with reference to FIG. 3, the aging condition optimizing means 100 is provided as the integrated circuit 28 on the head substrate 1A and has a detection function 200 for detecting a change in the resistance value of the heating resistor (heater) 23 (see FIG. 3). 25, 25A, 25B, 2
8 corresponds to this). Further, the optimum aging condition setting function 3 for setting the optimum aging condition based on the detection signal from the heater resistance value detection function 200
Has 00. Optimal aging condition setting function 300
Is composed of a heating signal setting function 400 for aging processing supplied to the heater 23 and a substrate temperature control function 500 for controlling the temperature of the head substrate 1A. Here,
Although not shown, the substrate temperature control function 500 includes means for heating and cooling the substrate and means for continuously detecting the substrate temperature.

Therefore, in manufacturing the liquid jet recording head 1 according to the present invention, the heater 23 and the peripheral portion thereof are subjected to the heat treatment in accordance with the aging treatment conditions obtained by the aging condition optimizing means 100 as described above. It is possible to realize a head capable of maintaining a stable ink ejection function.

The design values of the head constituent elements used in the heat treatment and the evaluation method thereof will be described below under the conditions obtained by the present inventor by the above-mentioned aging condition optimizing means.

Design values related to the components of the recording head: Substrate Si (with SiO ₂ thermal oxide film) 1.0 mm ± 10% Heating resistor HfB ₂ (sputtered film) 0.1 μm ± 10% Electrode Al 0.5 μm ± 10 % Protective film SiO ₂ 1.5 μm ± 10% Evaluation condition: The change in print quality depending on the number of prints was evaluated on a scale of five.

That is, the print quality is evaluated in five stages by a landing point error measuring method in which the amount of deviation of each vertical line in the printed matter from the least squares line is measured by observing all flying droplet landing dots with a microscope. Performed 1 (bad) → 5 (good).

The measurement results of the experiment will be described in detail below with reference to the drawings.

Experimental Example 1: When a large number of liquid jet recording heads having the structure shown in FIG. 2 were prototyped and a voltage and a pulse width were applied to the heater 23 for a certain time (1 minute in this embodiment). The change in the resistance value of the heater 23 was measured. The results are shown in FIGS. 6 and 8. Now, a high-frequency signal with an applied pulse width of 3 μsec is applied to the heater 23, and the voltage at the time when foaming starts is V0, while the applied voltage applied in this experiment is V, and the ratio is kv value (= V / V
0). Alternatively, the pulse width applied to the ink near the heater 23 is 3 μsec (the initial applied pulse width is P0 (μ
sec)) is applied and the voltage value at the start of foaming is fixed, the above-mentioned initial pulse width P0 (μsec)
On the other hand, the pulse width actually applied is P (μsec), and its ratio is the kp value (= P / P0). Also △ R
Shows the rate of change (R / R0) of the resistance value R (Ω) of the heater 23 when a voltage and a pulse width are applied to the heater 23 for a certain period of time with respect to the initial resistance value R0 (Ω) of the heater 23.

The difference between the results of FIGS. 6 and 8 is that the material of the heater 23 is different. 6 and 8, k1 is the heater 2
3 is the value of kv value and kp value immediately before the resistance value R changes, k2 is the value of kv value and kp value when the resistance value R of the heater 23 changes ± 1%, and k3 is the resistance value R of the heater 23 Of kv value and kp value when k changes by ± 5%, k
4 is k when the resistance value R of the heater 23 changes by ± 10%
It is a value of v value and kp value. As described above, the values of the kv value and the kp value related to the voltage and the pulse width change according to the change of the resistance value R, and the relationship between these values and the resistance value change rate of the heater 23 is approximately as shown in FIG. As shown in FIG.

Heater heating was performed under the following two conditions using the above values.

Condition for applying electric signal for heater heating treatment: Under the above-mentioned two electric signal application conditions for heater heating processing, the respective values of kv, kp, k1, k2, k3, and k4 are used to perform heater heating processing (hereinafter referred to as aging heating processing) on the liquid jet recording head. After doing
The print quality was evaluated by the number of prints. 7 and 9 show
kv and kp are represented as an average value of 10 heads for each value of k1, k2, k3 and k4.
Here, the values of k1, k2, k3, and k4 are k
Although it depends on the v value (condition 1) and the kp value (condition 2), the print quality evaluation by the number of prints at these values is
The results are almost as shown in FIGS. 7 and 9, respectively.

In FIG. 10, the life of the head is defined as the time when the print quality of the above-mentioned head becomes 1 (bad) out of the 5 grades, and the life is 1 for each of k1, k2, k3 and k4.
This is the result represented by the average value of 0 heads. Also in this case, the kv value and kp are actually set for each of the values k1, k2, k3, k4.
Although it is slightly different depending on the value, the life of the head is roughly as shown in FIG.

As is apparent from FIGS. 6 to 10, when the pulse width and / or the voltage value of the electric signal for aging heat treatment when the change in the resistance value of the heater changes within ± 5%, the change in the resistance value of the heater is used. Changes by ± 5% or more,
Or, when the pulse width of the electric signal for aging heat treatment when there is no change and / or the voltage value is used, the resistance value R of the heater is less deteriorated, stable and good print quality can be obtained, and the life is shortened. A long liquid jet recording head could be obtained. Furthermore, when the resistance value of the heater changes within ± 1%, the pulse width of the electric signal for aging heat treatment and / or the voltage value can be used to reduce deterioration of the resistance value of the heater, resulting in more stable and better print quality. It was possible to obtain a liquid jet recording head which is obtained and has a longer life.

Experimental Example 2: In the present experimental example 2, a large number of liquid jet recording heads 1 each having the structure shown in FIG. 2 were prototyped, and were completely ejected in a state filled with ink before being mounted in the liquid jet recording apparatus. The effect of aging heat treatment when the temperature of the head substrate 1A was changed by ejecting ink from the outlet 22 was examined.

The aging heat treatment was performed under the following conditions.

Aging heat treatment condition: Applied pulse width: 3 (μsec) Applied voltage: kv × V0 = 9 to 10 (V) (here, kv value is a value when the heater resistance change rate is ± 5%) Applied frequency: 4 (kHz) Number of applied pulses: 10 ⁶ pulse Head substrate temperature: 10 ° C., 40 ° C., 60 ° C. Under the aging heat treatment conditions described above, each of the ten heads was kept at the above head substrate temperature. As described above, each head was subjected to aging by using the optimum applied voltage value, and then the print quality was evaluated by the number of prints.

FIG. 11 shows the head substrate temperature of 10 ° C. and 40 ° C.
It is the result of the quality evaluation expressed by the average value of 10 heads when the respective values of ° C and 60 ° C are set. The above-mentioned substrate temperature of 60 ° C. is the maximum substrate temperature under the condition that stable stable repeated ejection of liquid can be maintained in each liquid jet recording head 1 used in this experimental example.

In FIG. 12, the print quality of the above-mentioned head 1 is 5
This is the result of expressing the average life value of 10 heads for each substrate temperature, with the time when the head becomes 1 (bad) in the graded evaluation as the life of the head.

As is clear from FIGS. 11 and 12, the substrate temperature of the liquid jet recording head is set to the recording head in order to heat the individual liquid jet recording head under the optimum aging condition suitable for each. By setting the temperature within the condition that 1 can maintain stable repeated discharge, the resistance value R of the heater 23 is less deteriorated, and stable and good print quality can be obtained. It is possible to obtain a liquid jet recording head whose life is not affected.

While the applied pulse width was constant under the above-mentioned aging conditions, stable and good print quality with little deterioration of the resistance value of the heater was obtained even when the applied voltage was constant. It was confirmed to obtain a liquid jet recording head in which the life of the head is not affected by the wafer.

Experimental Example 3: Also in this example, a large number of liquid jet recording heads 1 each having the structure shown in FIG. 2 were prototyped, and before being mounted on the liquid jet recording apparatus, they were filled with ink and the following conditions were satisfied. The ink was ejected from all the ejection ports 22 under the conditions described above to examine the effect of the aging heat treatment.

In this example, first, for comparison, aging was performed under the aging treatment conditions according to the conventional manufacturing method.

Conventional aging heat treatment condition: Applied pulse width: 3 (μsec) Applied voltage: kv × V0 = 9 to 10 (V) (where kv value is the condition value of the conventional aging treatment method, kv = 1.15 was used.) Applied frequency: 4 (kHz) Applied pulse number: 10 ⁶ pulses In FIG. 13, different heads A, B and C were all aged under the above-mentioned aging heat treatment conditions, and then printed. It is the result of expressing the print quality evaluation by the number for each liquid jet recording head. As shown in this figure, despite the aging heat treatment, the aging heat treatment to the heater is not sufficient due to variations in film distribution in the wafer surface due to film formation and variations in film thickness between wafers, On the contrary, since the treatment is too strong and the resistance of the heater is deteriorated, stable and good print quality is not obtained.

FIG. 14 shows that the heads obtained by the conventional aging heat treatment as described above have the life of the head at the time when the print quality becomes 1 (bad) in the 5 grade evaluation. It is the result of expressing the life by the average value for each head. From this, it can be seen that variations in the film distribution on the wafer surface due to film formation and variations in the film thickness between wafers appear in the life of the head.

Next, the above-mentioned reference example was subjected to aging under the aging heat treatment conditions according to the manufacturing method of the present invention.

The Eging heat treatment conditions are as follows.

Aging treatment conditions: Applied pulse width: 3 (μsec) Applied voltage: kv × V0 = 9 to 10 (V) (here, kv value is ± 5 heater resistance change rate of each wafer deno sample heater) % Value) Applied frequency: 4 (kHz) Applied pulse number: 10 ⁶ pulse Head substrate temperature: 60 ° C. FIG. 15 shows the head substrate 1 according to the manufacturing method of the present invention.
As shown in FIG. 3, a heater 23 and a heating resistor 2 are provided on A.
5. A large number of liquid jet recording heads each having a substrate heat-retaining heater 26, a temperature sensor circuit 27, and an integrated circuit 28 connected thereto are manufactured, and three different liquid jet recording heads A, B, and C are selected from the liquid jet recording heads. The print quality evaluations are shown below for which the optimum aging treatment according to the present invention has been performed on any of these. As is clear from this figure, as a result of the optimum aging process being performed on each of the recording heads A, B, and C, variations in the film distribution in the wafer surface due to the film forming technique and the film thickness of the wafer itself Although there is a slight difference due to variations in the above, the resistance value of the heater was not significantly deteriorated, and stable and good print quality was obtained.

FIG. 16 is a result showing the life of each of the recording heads A, B, and C, where the life of the head is the time when the print quality becomes 1 (bad) in the 5-step evaluation. . From this, it can be seen that there is no difference in the life of the head even if there are variations in the film distribution on the wafer due to film formation and variations in the film thickness between wafers.

As is clear from FIGS. 13 to 16 described above, the resistance value R of the heater is deteriorated by performing the treatment on the different liquid jet recording heads under the optimum aging heating condition suitable for each. It was possible to obtain a liquid jet recording head in which a small amount, stable and good printing quality was obtained, and the life of the head was not influenced by the wafer.

Experimental Example 4: In this example, a large number of liquid jet recording heads 1 each having the structure shown in FIG. 2 were prototyped and before being mounted in the liquid jet recording apparatus,
Instead of pulsed current, heating was performed with direct current, and aging heat treatment was performed as follows.

In the case of this example, a direct current is applied for 60 seconds between the common electrode (23B) of the head 1 and each selection electrode (23A). And the current value is 1 mA to 100
Change the print quality between 10 mA and 10
It was calculated as the average value of the individual heads.

As a result, as shown in FIG. 17, the effect of aging was remarkably exhibited when the current supplied per heater was set to 30 mA or more. In the case of this example, the bubbling and the ejection of the ink are not performed even when the head 1 is filled with the ink, but the effects obtained as the surface treatment of the heater are as follows. It was similar to the case.

However, in the case of this example, it is only necessary to control the substrate temperature via the integrated circuit 28 without providing the heating resistor 25 on the substrate 1A.

(Others) The present invention is particularly provided with a means (for example, an electrothermal converter or a laser beam) for generating thermal energy as energy used for ejecting ink, even in the ink jet recording system. The present invention brings about excellent effects in a recording head and a recording apparatus of the type in which the state of ink is changed by the heat energy. This is because such a system can achieve high density recording and high definition recording.

Regarding its typical structure and principle, see, for example, US Pat. No. 4,723,129 and US Pat. No. 4,740.
What is done using the basic principles disclosed in 796 is preferred. This method is a so-called on-demand type,
It can be applied to any of the continuous type, but especially in the case of the on-demand type, it can be applied to the sheet holding the liquid (ink) or the electrothermal converter arranged corresponding to the liquid path. By applying at least one drive signal corresponding to the recording information and giving a rapid temperature rise exceeding nucleate boiling, heat energy is generated in the electrothermal converter, and film boiling is caused on the heat acting surface of the recording head. Liquid (ink) corresponding to this drive signal in a one-to-one correspondence
It is effective because bubbles can be formed inside. Due to the growth and contraction of the bubbles, the liquid (ink) is ejected through the ejection opening to form at least one droplet. It is more preferable to make this drive signal into a pulse shape because bubbles can be immediately and appropriately grown and contracted, so that liquid (ink) ejection with excellent responsiveness can be achieved. As the pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. If the conditions described in US Pat. No. 4,313,124 of the invention relating to the rate of temperature rise on the heat acting surface are adopted, more excellent recording can be performed.

As the constitution of the recording head, in addition to the combination constitution of the discharge port, the liquid passage, and the electrothermal converter (the linear liquid passage or the right-angled liquid passage) as disclosed in the above-mentioned specifications, US Pat. No. 4,558,333, US Pat. No. 4,558,333, which discloses a configuration in which a heat acting portion is arranged in a bending region.
The structure using the specification of No. 59600 is also included in the present invention. In addition, Japanese Unexamined Patent Publication No. 59-123670 discloses a configuration in which a common slit is used as a discharge portion of the electrothermal converter for a plurality of electrothermal converters, and an opening for absorbing a pressure wave of thermal energy is provided. The effect of the present invention is effective even if the configuration corresponding to the ejection portion is disclosed in JP-A-59-138461. That is, according to the present invention, recording can be surely and efficiently performed regardless of the form of the recording head.

Further, the present invention can be effectively applied to a full line type recording head having a length corresponding to the maximum width of a recording medium which can be recorded by the recording apparatus. Such a recording head may have a configuration that satisfies the length by a combination of a plurality of recording heads or a configuration as one recording head integrally formed.

In addition, even in the case of the serial type as in the above example, the recording head fixed to the apparatus main body, or the electrical connection with the apparatus main body or the ink from the apparatus main body by being attached to the apparatus main body The present invention is also effective when a replaceable chip-type recording head that can be supplied or a cartridge-type recording head in which an ink tank is integrally provided in the recording head itself is used.

Further, as the constitution of the recording apparatus of the present invention, it is preferable to add the ejection recovery means of the recording head, the preliminary auxiliary means and the like because the effects of the present invention can be further stabilized. Specifically, heating is performed by using a capping unit, a cleaning unit, a pressure or suction unit for the recording head, an electrothermal converter or a heating element other than this, or a combination thereof. Examples thereof include a preliminary heating unit for performing the discharge and a preliminary discharge unit for performing discharge different from the recording.

Regarding the type and number of recording heads to be mounted, for example, only one is provided corresponding to a single color ink, or a plurality of inks having different recording colors and densities are supported. A plurality of pieces may be provided. That is, for example, the recording mode of the recording apparatus is not limited to the recording mode of only the mainstream color such as black, but it may be either the recording head is integrally formed or a plurality of combinations may be used. The present invention is also extremely effective for an apparatus provided with at least one of full-color recording modes by color mixing.

In addition, in the above-described embodiments of the present invention, the ink is described as a liquid, but an ink that solidifies at room temperature or lower and that softens or liquefies at room temperature may be used. Or, in the inkjet system, it is common to control the temperature of the ink itself within the range of 30 ° C. or higher and 70 ° C. or lower to control the temperature so that the viscosity of the ink is within the stable ejection range. Sometimes, a liquid ink may be used. In addition, the temperature rise due to thermal energy is positively prevented by using it as the energy of the state change of the ink from the solid state to the liquid state, or in order to prevent the evaporation of the ink, it is solidified and heated in the standing state. You may use the ink liquefied by. In any case, by applying thermal energy such as ink that is liquefied by applying thermal energy according to the recording signal and liquid ink is ejected, or that begins to solidify when it reaches the recording medium. The present invention can be applied to the case where an ink having a property of being liquefied for the first time is used. In this case, the ink is
JP-A-54-56847 or JP-A-60-7
As described in Japanese Patent No. 1260, it may be configured to face the electrothermal converter in a state of being held as a liquid or a solid in the concave portion or the through hole of the porous sheet. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

In addition, as a form of the ink jet recording apparatus of the present invention, other than the one used as an image output terminal of an information processing apparatus such as a computer, a copying apparatus combined with a reader or the like, and a facsimile apparatus having a transmitting / receiving function are provided. It may be a form or the like.

[0086]

As described above, according to the present invention, an electric signal sufficient to stabilize the resistance value of the heat generating resistor is applied to the heat generating resistor via the electrode, and the heat generated by the heat generating resistor is applied. On the substrate of the liquid jet recording head, a control means for optimizing the aging condition is integrated into an integrated circuit in order to optimize the aging condition in the aging process of the heating resistor performed in the heat treatment. Installed in
By performing the aging process through the integrated circuit, it is possible to suppress the change in the resistance value of the heating resistor within a suitable range for always obtaining a good droplet discharge state from the initial stage of recording. In particular, it is possible to propose a method for manufacturing a liquid jet recording head, which can easily and inexpensively obtain a liquid jet recording head which can always maintain a good and stable droplet discharge state even in recording for a long time.

Further, it is possible to propose a method of manufacturing a liquid jet recording head which can easily obtain a liquid jet recording head having a long life with a high yield against repeated heat generation for a long time in the heating resistor of the recording head. .

Further, a liquid which suppresses the manufacturing variation and improves the wettability between the recording liquid and the heating resistor or between the recording liquid and the liquid passage to obtain a good and stable droplet discharge state. It is possible to propose a method for manufacturing a liquid jet recording head that can easily and inexpensively manufacture the jet recording head.

Furthermore, since the good and stable droplet discharge state can be maintained at all times, the change in the resistance value of the heating resistor is suppressed within a suitable range, and particularly in the long-term recording, the good and stable droplets are always maintained. It is possible to easily and inexpensively provide a liquid jet recording head that can obtain a discharged state with a high yield.

Further, it is possible to easily and inexpensively provide a liquid jet recording head having a long life with respect to repeated heat generation in the heating resistor of the recording apparatus for a long period of time.

Furthermore, a liquid capable of suppressing variations in manufacturing and improving the wettability between the recording liquid and the heating resistor or between the recording liquid and the liquid passage to obtain a good and stable droplet discharge state. It is possible to easily and inexpensively provide the jet recording head with a high yield.

Furthermore, it is possible to provide a liquid jet recording apparatus equipped with a liquid jet recording head having excellent characteristics as described above.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a liquid jet recording apparatus according to the present invention.

2 is a perspective view showing an example of the configuration of a liquid jet recording head according to the present invention mounted on the apparatus of FIG.

3 is a configuration diagram of a circuit on a head substrate of the liquid jet recording head shown in FIG.

FIG. 4 is a plan view showing an example of an arrangement of a head substrate according to the present invention on a wafer.

FIG. 5 is an explanatory diagram of means for optimizing aging processing conditions according to the present invention.

FIG. 6 is an explanatory diagram for determining a kv value and / or a kp value from a heater resistance value change rate ΔR.

FIG. 7 is a characteristic curve diagram showing the relationship between the print quality and the number of prints with the kv value and / or the kp value as parameters.

FIG. 8 is an explanatory diagram for determining a kv value and / or a kp value from a heater resistance value change rate ΔR.

FIG. 9 is a characteristic curve diagram showing the relationship between the print quality and the number of prints with the kv value and / or the kp value as parameters.

FIG. 10 is a graph showing the relationship between the kv value and / or kp value and the life of the liquid jet recording head.

FIG. 11 is a characteristic curve diagram showing the relationship between the print quality and the number of prints with the head substrate temperature as a parameter.

FIG. 12 is a graph showing the relationship between the head substrate temperature and the life of the liquid jet recording head.

FIG. 13 is a characteristic curve diagram showing the relationship between the print quality and the number of prints for three different liquid jet recording heads that have been aged by the manufacturing method of the present invention.

FIG. 14 is a graph showing a comparison of lifespans of the three liquid jet recording heads shown in FIGS. 13 and 15.

FIG. 15 is a characteristic curve diagram showing the relationship between the print quality and the number of prints for three different liquid jet recording heads that have been aged by the manufacturing method of the present invention.

16 is a graph showing a comparison of the lives of the three liquid jet recording heads shown in FIGS. 13 and 15. FIG.

FIG. 17 is a characteristic curve diagram showing a relationship between print quality and a direct current value used for heat aging treatment.

[Explanation of symbols]

1 recording head 1A substrate 2 carriage 3 sub tank 11 Flexible printed wiring board 12 Discharge signal generating means 13 Preliminary ejection processing control means 14 Preheating treatment control means 21 liquid path 22 Discharge port 23 heater 23A, 23B electrodes 25 Heating resistor 26 Substrate temperature control means 27 Substrate temperature detection means 28 integrated circuits 30 wafers 100 Aging condition optimization means 200 Heating resistor resistance value detection function 300 Optimal aging condition setting function 400 Aging process heating signal setting function 500 Substrate temperature control function

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location H01C 17/06 M 9058-5E

Claims (24)

[Claims] 1. An electrothermal converter including a heating resistor for generating thermal energy used to eject a recording liquid and an electrode for applying an electric signal to the heating resistor, on a head substrate. In the method of manufacturing a liquid jet recording head having the above-mentioned heat generation, a sufficient electric signal for stabilizing the resistance value of the heat generation resistor is applied to the heat generation resistor via the electrode, and the heat treatment is performed by the heat generation. In the aging process of the resistor, in order to optimize the aging condition, a control means for optimizing the aging condition is integrated into a circuit and is provided on the substrate of the liquid jet recording head, and via the integrated circuit, A method for manufacturing a liquid jet recording head, characterized in that the aging treatment process is performed. 2. The integrated circuit has a function of detecting a resistance change value of the heating resistor, a function of setting an optimum electric signal based on the detected value, and a method of applying the set optimum electric signal. A combination of at least two or more of the functions of controlling the substrate temperature to be maintained at a predetermined temperature is provided as an integrated circuit on the substrate, and the aging process is performed through the integrated circuit. A method of manufacturing a liquid jet recording head according to claim 1. 3. The method for manufacturing a liquid jet recording head according to claim 1, wherein the optimum electric signal applied to the heating resistor for the aging process is a high frequency signal. 4. The optimum electric signal applied to the heating resistor for the aging process is larger in pulse width than an electric signal for generating thermal energy used for ejecting the recording liquid, and / or The liquid jet recording head manufacturing method according to claim 1, wherein the liquid jet recording head has a voltage value. 5. The electric signal setting function sets the electric signal based on resistance value change information of the heating resistor obtained from a function of detecting a change value of the resistance value of the heating resistor. A method for manufacturing a liquid jet recording head according to claim 1, wherein the liquid jet recording head is manufactured. 6. The resistance value detecting function includes a circuit that outputs a pulse width and / or a voltage value of the electric signal for a certain period of time, and the heating resistor after the output of the pulse width and / or the voltage value is completed. 6. A method for manufacturing a liquid jet recording head according to claim 5, further comprising a circuit for measuring a body resistance value. 7. The optimum electric signal uses a pulse width and / or a voltage value when the resistance value of the heating resistor changes within ± 5% by at least the resistance value detecting function. The method for manufacturing a liquid jet recording head according to claim 5. 8. The optimum electric signal uses at least a pulse width and / or a voltage value when the resistance value of the heating resistor changes within ± 1% by the resistance value detecting function. The method for manufacturing a liquid jet recording head according to claim 5. 9. The function of controlling the substrate to be maintained at a set predetermined temperature includes a circuit for detecting the temperature of the substrate and a circuit for heating and cooling at least the substrate. 1. A method of manufacturing a liquid jet recording head according to item 1. 10. The function of controlling the substrate to be maintained at a set predetermined temperature is such that the substrate temperature is close to a temperature within a condition in which repeated ejection of liquid can be maintained even if the temperature of the substrate is raised. The method for manufacturing a liquid jet recording head according to claim 1, wherein the method is controlled. 11. The function of controlling the substrate so as to keep it at a set predetermined temperature is such that the substrate has a temperature close to the maximum temperature under the condition that the liquid can be repeatedly ejected even if the temperature of the substrate is increased. The method of manufacturing a liquid jet recording head according to claim 1, wherein the temperature is controlled. 12. A heating resistor, which is formed of the same material and has the same shape as the heating resistor constituting the electrothermal converter and is used for the resistance value change detecting function, and to keep the substrate at a predetermined temperature. 11. The liquid jet recording according to claim 1, wherein the substrate temperature detecting means and the substrate temperature controlling means used in the above are connected to the integrated circuit and arranged on the substrate. Head manufacturing method. 13. The optimum electric signal and the substrate temperature are set before the aging process in the heating process of the heating resistor in order to optimize the aging process conditions. 1. A method of manufacturing a liquid jet recording head according to item 1. 14. The method of manufacturing a liquid jet recording head according to claim 1, wherein the optimum electric signal is a DC electric signal. 15. The method for manufacturing a liquid jet recording head according to claim 11, wherein the optimum electric signal is applied as a direct current value of 30 mA or more per the heating resistor. 16. The method of manufacturing a liquid jet recording head according to claim 1, wherein the aging process is performed after the liquid jet recording head is completed and before the liquid jet recording head is mounted on the liquid jet recording apparatus. 17. The method of manufacturing a liquid jet recording head according to claim 1, wherein the aging treatment is performed during the manufacturing of the liquid jet recording head and after the electrothermal converter is formed. 18. The method for manufacturing a liquid jet recording head according to claim 1, wherein the aging process is performed after the completed liquid jet recording head is mounted on the liquid jet recording apparatus. 19. The method of manufacturing a liquid jet recording head according to claim 17, wherein the aging process is performed in a state where the liquid jet recording head is filled with ink. 20. The method for manufacturing a liquid jet recording head according to claim 17, wherein the aging process is performed in a state where the liquid jet recording head is not filled with ink. 21. A liquid jet recording head manufactured by the method for manufacturing a liquid jet recording head according to claim 1. 22. An electrothermal converter having a heating resistor for generating thermal energy used to eject the recording liquid and an electrode for applying an electric signal to the heating resistor is provided on the substrate. A liquid jet recording head, wherein an aging process of the heating resistor is performed by applying a sufficient electric signal to stabilize the resistance value of the heating resistor through the electrode and performing heat treatment by the heat generation. In order to optimize the aging processing conditions, the liquid ejecting recording head in which a control means integrated circuit for optimizing the aging conditions is disposed on the substrate during head manufacturing,
And a means for optimizing the ejection of liquid from the liquid jet recording head. 23. The means for optimizing the discharge of the recording liquid is at least one of a preliminary discharge processing control means, a preliminary heating processing control means, and a recovery processing control means,
Alternatively, the liquid jet recording apparatus according to claim 21, which includes a combination of two or more. 24. An electrothermal converter having a heating resistor for generating thermal energy used for discharging a recording liquid and an electrode for applying an electric signal to the heating resistor is provided on a substrate. In manufacturing the liquid jet recording head, an electric signal which is sufficient for stabilizing the resistance value of the heating resistor and which is different from a signal applied during image recording, preliminary ejection processing or preliminary heating processing is applied to the electrode. In the aging process of the heating resistor, the substrate is applied with an optimum electric signal set by an electric signal setting means in order to optimize the aging process condition. A method of manufacturing a liquid jet recording head, characterized in that the aging process is controlled via a control circuit on the substrate for controlling the temperature to be kept at a predetermined temperature. Law.