JPH08300669A - Production of liquid jet recording head - Google Patents

Abstract

PURPOSE: To prevent the shift of the cross-sectional dimension of each of the liquid passages of a nozzle layer made of a photosensitive resin from a plan value. CONSTITUTION: A nozzle layer 20 made of a photosensitive resin is laminated on a substrate 10 having emission energy generating elements 11 and liquid passages 21 are formed to the nozzle layer by photolithography. A common liquid chamber layer 30 composed of a photosensitive resin is laminated thereon and patterned by photolithography to form a common liquid chamber 31. In the patterning process of the common liquid chamber 31, the air in the liquid passages 21 is substituted with nitrogen and the common liquid chamber layer 30 is exposed in such a state that oxygen is not contained in the atmosphere of the liquid passages 21.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid jet recording head used in a liquid jet recording apparatus for recording (printing) on a recording paper or the like by ejecting recording liquid (ink) as droplets from fine discharge holes (orifices). The present invention relates to a manufacturing method of.

[0002]

2. Description of the Related Art Recording liquid (ink) is discharged as droplets from fine discharge holes (orifices) to record (print) on recording paper or the like.
In a liquid jet recording head of a liquid jet recording apparatus for performing the above, generally, on a substrate provided with an ejection energy generating element, a liquid flow path (nozzle) for flowing a recording liquid and a nozzle layer forming a common liquid chamber are laminated. It has a laminated structure.

In manufacturing the nozzle layer, first, a liquid flow path or the like is grooved by cutting or etching on the surface of a plate material such as glass or metal, and the plate material thus grooved is used as an ejection energy generating element. After aligning with a substrate provided, or by bonding, or forming a resist pattern such as a liquid flow path on the substrate by known lithography or the like,
A method of applying a resin layer so as to cover this and then eluting the resist pattern (see Japanese Patent Application Laid-Open No. 62-154947) is used.

Further, in recent years, a liquid jet recording head capable of obtaining stable ejection performance even when the ejection frequency is high is required, as the printing speed is further advanced with the increase in the number of nozzles and the density of the nozzles. In order to satisfy such conditions, a liquid in which a nozzle layer having only a liquid flow path, a common liquid chamber layer having only a common liquid chamber, and a lid covering the common liquid chamber are sequentially laminated on a substrate A jet recording head was developed.

FIG. 6A is a perspective view showing a liquid jet recording head E _{0 according} to a conventional example, in which a plurality of liquid flow paths 121 are first formed on a substrate 101 having an ejection energy generating element (not shown). Nozzle layer 12 of photosensitive resin having
0 is formed by known photolithography, a common liquid chamber layer 130 of the same photosensitive resin is formed thereon by similar photolithography, and a lid 140 is laid on the common liquid chamber layer 130. The common liquid chamber 131 is configured so as to cover most of the ceiling of each liquid flow channel 121 of the layer 120, and the overhanging portion 131a of the common liquid chamber 131 overlaps with a part of the ceiling of each liquid flow channel 121 of the nozzle layer 120, so that the communication port 12 is formed.
1a, and the lid 140 is a common liquid chamber 13
1 is provided with an injection port 141 for supplying a recording liquid (ink).

After the droplets are discharged from the discharge port 122 of each liquid flow path 121, the recording liquid in the common liquid chamber 131 is replenished from the communication port 121a on the ceiling of the liquid flow path 121. As described above, by closing the rear end of each liquid flow path 121 and replenishing the recording liquid from the communication port 121a of the ceiling, the replenishment of the recording liquid is performed very quickly, and the liquid jet recording head having a high response frequency of droplet ejection. Can be realized (see Japanese Patent Laid-Open Nos. 61-110557 and 61-110558).

In addition, when the rear end of the liquid flow path is closed and the cross section of the rear portion of the liquid flow path is reduced or the shape thereof is devised to reduce the amount of the recording liquid flowing back from the ejection port, A liquid jet recording head having a higher response frequency and stable ejection performance can be obtained.

Since the nozzle layer and the common liquid chamber layer are required to have ink resistance, a photocurable resin is used as the photosensitive resin forming them. In addition, since the liquid flow path and the discharge port require high dimensional accuracy, it is common to use a radical-polymerizable photo-curable photosensitive resin that enables photolithography with particularly high pattern accuracy. Target.

[0009]

However, according to the above-mentioned conventional technique, as described above, the radical polymerizable photo-curable resin is used as the photosensitive resin forming the nozzle layer and the common liquid chamber layer. In the step of forming the common liquid chamber layer on the nozzle layer, oxygen in the air remaining in the liquid flow channel of the nozzle layer inhibits the curing reaction of the common liquid chamber layer, and the portion facing the liquid flow channel is Since it is left unhardened, there arises a problem that the ceiling of the liquid flow path is removed as shown in FIG. 6B in the developing process of the common liquid chamber layer. When the ceiling of the liquid flow path is thus scooped, the cross-sectional dimension of the liquid flow path is significantly deviated from the designed value, and desired discharge performance cannot be obtained.

Further, as shown in FIG. 7A, the substrate 2
01 is provided with a nozzle layer 220 having a liquid flow path 221, and a common liquid chamber 231 is formed by cutting or etching a top plate 230 made of glass or metal to form a common liquid chamber 231 with an adhesive 250. Although a method of adhering to the upper nozzle layer 220 has been developed, the top plate 2
It is difficult to perform the alignment of the nozzle 30 and the nozzle layer 220 with high precision, and as shown in FIG.
Part of the liquid flows into the liquid channel 221 of the nozzle layer 220,
For this reason, the cross-sectional size of the liquid flow channel 221 is reduced, and it is difficult to obtain stable ejection performance as designed.

Further, when the nozzle layer is formed by metal plating and the top plate is also made of metal, diffusion welding is performed in which the nozzle layer and the top plate are heated in vacuum without using an adhesive. A method employing the method has also been proposed (see Japanese Patent Laid-Open No. 57-113075). However, also in this case, it is difficult to align the nozzle layer and the top plate with high accuracy, and the material of the substrate may deteriorate due to high temperature heating, and the mass productivity is low. There is.

The present invention has been made in view of the above-mentioned problems of the prior art. In photolithography for patterning a liquid flow path and a common liquid chamber in a photosensitive resin layer, the cross-sectional dimension of the liquid flow path, etc. It is an object of the present invention to provide a method for manufacturing a liquid jet recording head, which can prevent a significant deviation from a design value and can obtain stable ejection performance.

[0013]

In order to achieve the above object, a method of manufacturing a liquid jet recording head according to the present invention comprises laminating a first photosensitive resin layer on a substrate having an ejection energy generating means and performing photolithography. After patterning a liquid flow path on the first photosensitive resin layer, a second photosensitive resin layer is laminated and the second photosensitive resin layer is formed by photolithography.
In the photolithography for patterning the common liquid chamber in the photosensitive resin layer, the atmosphere of the liquid flow path contains a component that prevents curing of the second photosensitive resin layer. The second photosensitive resin layer is exposed in the absence of light.

The air in the liquid flow path may be replaced with an inert gas.

[0015]

In the photolithography for patterning the common liquid chamber in the second photosensitive resin layer, the liquid flow path of the first photosensitive resin layer remains filled with air during the exposure of the second photosensitive resin layer. If there is oxygen, etc., the second
However, the curing of the photosensitive resin layer is impeded, resulting in local inadequacy. As a result, in the developing process of the second photosensitive resin layer, the second
The photosensitive resin layer may be removed more than necessary, and the ceiling of the liquid flow path may be scooped out, resulting in a large deviation in the cross-sectional dimension of the liquid flow path from the design value.

Therefore, the air in the liquid flow path is replaced with an inert gas or the like, and the atmosphere of the liquid flow path does not contain oxygen or the like that hinders the hardening of the second photosensitive resin layer. To prevent the curing of the second photosensitive resin layer from being locally insufficient.

In this way, it is possible to obtain a liquid jet recording head which has a liquid flow path having a cross-sectional dimension according to the design value and therefore has stable ejection performance.

[0018]

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows a liquid jet recording head E _{1 according} to one embodiment, which is a first photosensitive resin layer on a substrate 10 having a discharge energy generating element 11 which is a discharge energy generating means. A nozzle layer 20 is laminated, and a plurality of liquid flow paths 2 are formed on the nozzle layer 20 by known photolithography.
1 is patterned, a common liquid chamber layer 30 which is a second photosensitive resin layer is laminated thereon, a common liquid chamber 31 is patterned by photolithography, and a lid 40 is superposed thereon. The chamber layer 30 is configured so as to cover most of the ceiling of each liquid flow path 21 of the nozzle layer 20, and the common liquid chamber 31 has a projecting portion 31 a in the liquid flow path 21 of the nozzle layer 20.
A communication port 21a is formed so as to overlap with a part of the ceiling of the lid, and the lid 40 has an injection port 41 for supplying the recording liquid (ink) to the common liquid chamber 31.

After the liquid droplets are discharged from the discharge ports 22 of each liquid flow path 21, the recording liquid in the common liquid chamber 31 is replenished from the communication port 21a on the ceiling of the liquid flow path 21. In this way, by closing the rear end of each liquid flow path 21 and replenishing the recording liquid from the communication port 21a of the ceiling, the replenishment of the recording liquid is performed very quickly,
It is possible to realize a liquid jet recording head having a high response frequency of droplet discharge.

The liquid jet recording head E ₁ is manufactured as follows. First, as shown in FIG.
A coating film of a photosensitive resin is provided on the substrate 0, and the coating is patterned by known photolithography to form a nozzle layer 20 having a liquid flow path 21. On top of that, as shown in FIG. 3, a photosensitive resin coating film 30 which is cured by radical polymerization.
a is provided. This is manufactured, for example, using the photosensitive resin having the composition shown in Table 1 as follows.

[0022]

[Table 1] A solution containing a double amount of a mixed solution of toluene and ethyl cellosolve mixed with the photosensitive resin shown in Table 1 at a mixing ratio of 1: 1 was prepared, and this solution was coated on a 25 μm thick polyester film with a wire bar coater. A resin layer having a thickness of 40 μm after coating and drying was obtained. This was pressure-bonded to the nozzle layer 20 with a laminator. Lamination conditions are pressure 1.5 kg / cm ² , temperature 30 ° C., feed rate 0.2 m.
/ S.

Next, as shown in FIG. 4A, a mask M having a light-shielding pattern P for the common liquid chamber is aligned on the photosensitive resin coating film 30a by a known method, and then, as shown in FIG. ), The air in the sealed box S is replaced with nitrogen. The process is performed as follows, for example.

First, the degassing valve V ₁ is opened, the gas introduction valve V ₂ is closed, and the vacuum pump leading to the degassing port is operated to evacuate the sealed box S to 1 mmHg or less. Next, the degassing valve V ₁ is closed and the gas introduction valve V ₂ is opened, and nitrogen, which is an inert gas, is introduced from there to raise the pressure to atmospheric pressure. This operation is repeated 10 times until the inside of the liquid flow path 21 of the nozzle layer 20 is completely filled with a nitrogen atmosphere, and then the aligner (P
LA-501 Canon Inc.) is used for UV exposure, and then spray development is performed with trichloroethane for 50 seconds to form a common liquid chamber 31 and a communication port 21a as shown in FIG.

Further, it is irradiated with ultraviolet rays at 10 J / cm ² ,
A lid 40 (see FIG. 1) having a filling port 41 after enhancing ink resistance is adhered to the common liquid chamber layer 30 with an adhesive, and finally an edge is diced (AWD-2500B / TC).
The liquid jet recording head E ₁ shown in FIG. ₁ is completed by cutting it with Tokyo Seimitsu Co., Ltd.).

According to this embodiment, before the exposure process for patterning the common liquid chamber layer 30, the deoxidizing process is performed to completely replace the air in each liquid flow path 21 of the nozzle layer 20 with nitrogen. Since the photosensitive resin coating film 30a is exposed in the atmosphere of the liquid flow passage 21 in the absence of oxygen, which is a component that hinders the curing of the photosensitive resin coating film 30a, oxygen that remains in the liquid flow passage 21 is exposed. Therefore, there is no possibility that radical polymerization of the photosensitive resin coating film 30a is hindered and the curing of a part thereof becomes insufficient. Therefore, unlike the conventional example, the ceiling of the liquid flow path 21 after development is scooped out, and the cross-sectional size of the liquid flow path 21 and the opening area of the communication port 21a with the common liquid chamber 31 are not remarkably enlarged, and FIG. As shown in (c), a liquid jet recording head having a flat ceiling of the liquid channel 21 and stable ejection performance with the cross-sectional dimensions of the liquid channel 21 and the opening area of the communication port 21a being as designed values is manufactured. You can

Note that an inert gas such as neon or argon can be used instead of nitrogen used for the deoxidation treatment.

According to the method of manufacturing the liquid jet recording head of this embodiment, the design value of the opening area of the discharge port (cross section of the liquid flow path) is 900 μm ² (30 μm × 30 μm), and the design value of the opening area of the communication port is 2000 μm. ² (40 μm x 50 μm)
100 liquid jet recording heads were manufactured, and as a first comparative example, 100 liquid jet recording heads of the above design value were manufactured without deoxidizing treatment before exposure in the same process as this embodiment. Then, as a second comparative example, instead of forming the common liquid chamber layer on the nozzle layer by photolithography, the lid is nickel-plated to form the common liquid chamber layer, and the common liquid chamber layer is bonded to the nozzle layer with an adhesive. By the method, 100 liquid jet recording heads having the above-mentioned design values were manufactured, and for a total of 300 liquid jet recording heads, the opening area of the discharge port and the communication port, the refill frequency, the droplet speed,
Table 2 shows the result of examining the flying dot diameter.

[0029]

[Table 2] Nozzle (liquid flow path) density: 400 dots / inch Number of nozzles (liquid flow path): 48 nozzles As can be seen from Table 2, the opening areas of the discharge port and the communication port of the liquid jet recording head according to this embodiment are both designed. The deviation from the value is slight, and the refill frequency is extremely high, and therefore high-speed printing is possible. Further, if the droplet speed has a large variation, the landing point of the flying dot will be inaccurate and the print quality will be deteriorated. 5m
/ S or less, and therefore high-quality printing can be performed. The design value of the flying dot diameter is 45 μm, and the variation for each sample is as small as ± 2 μm, and there is no risk of ink shortage on the printing surface, causing defects such as white spots.

On the other hand, in the liquid jet recording head according to the first comparative example, the opening areas of the discharge port and the communication port are both greatly expanded from the design value, the refill frequency is low, and the variation of the droplet speed is 3.0 m. / S, and the large flying dot diameter also tends to increase the ink consumption.

The liquid jet recording head according to the second comparative example is
The opening area of the discharge port and the communication port is smaller than the design value, the dispersion of the droplet speed is large at 4.5 m / s, and the flying dot diameter is extremely small at 30 to 45 μm, and the above-mentioned white spots occur. As a result, many problems such as a decrease in print density and unclear print may occur.

Next, Table 3 shows the results of a printing test at a driving frequency of 15 kHz using the above 300 liquid jet recording heads.

[0033]

[Table 3] As a result of using the liquid jet recording head according to this example, the print quality was extremely good, but in the first comparative example, splash development due to the low refill frequency was observed, and therefore the print quality was improved. It is presumed that it has decreased. It is presumed that in the third comparative example, the deviation of the droplet speed is large and the diameter of the flying dot is small, so that dot deviation and white spots are generated, and the print quality is significantly reduced.

The present invention provides excellent effects particularly in a so-called ink jet recording type recording head and recording apparatus for recording by forming flying droplets by utilizing thermal energy in the liquid jet recording method. Is.

Regarding the typical structure and principle thereof, for example, US Pat. Nos. 4,723,129 and 4740 are applicable.
No. 796, the present invention is preferably carried out using these basic principles. This recording method is applicable to both the so-called on-demand type and the continuous type.

To briefly explain this recording method, a drive circuit discharges an electrothermal converter, which is an ejection energy generating element, arranged in correspondence with a sheet holding a recording liquid (ink) or a liquid flow path. A signal is supplied, that is, nucleate boiling phenomenon is exceeded in the recording liquid (ink) corresponding to the recording information,
By applying at least one drive signal to provide a rapid temperature rise that results in a film boiling phenomenon,
Heat energy is generated to cause film boiling on the heat acting surface of the recording head. In this way, bubbles can be formed one-to-one corresponding to the drive signal applied from the recording liquid (ink) to the electrothermal converter, which is particularly effective for the on-demand recording method. The growth and contraction of the bubbles cause the recording liquid (ink) to be ejected through the ejection port to form at least one droplet. It is more preferable to make this drive signal into a pulse shape, because the bubble growth and contraction are immediately and appropriately performed, so that the ejection of the recording liquid (ink) with particularly excellent responsiveness can be achieved. As this pulse-shaped drive signal, US Pat.
Those described in US Pat. Nos. 4,633,359 and 4,345,262 are suitable. It should be noted that US Pat. No. 4,313, which is an invention relating to the rate of temperature rise of the heat acting surface
If the conditions described in the specification No. 124 are adopted, more excellent recording can be performed.

The structure of the recording head is a combination of a discharge port, a liquid flow path, and an electrothermal converter as disclosed in the above-mentioned specifications (straight liquid flow path or right-angled liquid flow path).
In addition to the above, the present invention is also effective for those having a configuration in which the heat acting portion is arranged in the bending region as disclosed in US Pat. No. 4,558,333 and US Pat. No. 4,459,600. .

In addition, JP-A-59-123670 discloses a structure in which a common slit is used as a discharge port of the electrothermal converter for a plurality of electrothermal converters, and a pressure wave of thermal energy is absorbed. The present invention is also effective for a device having a structure based on Japanese Patent Application Laid-Open No. 59-138461 which discloses a structure in which an opening corresponds to a discharge portion.

Further, as a recording head in which the present invention is effectively used, there is a full line type recording head having a length corresponding to the maximum width of the recording medium which can be recorded by the recording device. The full-line head may be a full-line recording head formed by combining a plurality of recording heads as disclosed in the above-mentioned specification, or a single full-line recording head integrally formed.

In addition, by being mounted on the apparatus main body, it can be electrically connected to the apparatus main body and can be supplied with ink from the apparatus main body by a replaceable chip type recording head or the recording head itself. The present invention is also effective when a cartridge-type recording head that is specially provided is used.

Further, it is preferable to add recovery means or preliminary auxiliary means to the recording head because the recording apparatus can be made more stable. Specific examples thereof include capping means, cleaning means, pressure or suction means, an electrothermal converter or a heating element other than the capping means, preheating means for the recording head, or a combination thereof. It is also effective to perform stable recording by adding a preliminary discharge mode means for performing discharge different from recording.

Further, the recording mode of the recording apparatus is not limited to the mode in which only the mainstream color such as black is recorded, and either the recording head may be integrally formed or a combination of plural recording heads may be used. However, the present invention is also extremely effective for an apparatus provided with at least one of a multicolor of different colors or a full color by color mixing.

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, in addition to the one used as an image output terminal of information processing equipment such as a computer, a copying apparatus combined with a reader or the like, and a facsimile apparatus having a transmitting / receiving function. It may take the form of.

In the embodiment of the present invention described above,
Although the ink is described as a liquid, it is an ink that solidifies at room temperature or lower and becomes a liquid or a liquid at room temperature, or a temperature range for temperature adjustment that is generally performed in inkjet. ℃ or more 70 ℃
It may be softened or become liquid in the following temperature range. That is, the ink may be in a liquid state when the use recording signal is applied. In addition, the temperature rise due to the 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 the ink that solidifies when left standing for the purpose of preventing the evaporation of the ink is used. In any case, the thermal energy such as the one that the ink is liquefied by applying the thermal energy according to the recording signal and ejected as an ink liquid, or the one that has already started to solidify when it reaches the recording medium. The use of an ink having the property of liquefying for the first time is also applicable to the invention. In such a case, the ink is disclosed in JP-A-54-5.
6847 or Japanese Unexamined Patent Publication No. 60-71260, a mode in which it is opposed to an electrothermal converter in a state of being held as a liquid or a solid in a recess or through hole of a porous sheet. May be In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

[0046]

Since the present invention is configured as described above, it has the following effects.

In photolithography in which a liquid flow path and a common liquid chamber are patterned in a photosensitive resin layer, a liquid jet having a stable discharge performance as designed is prevented from being significantly deviated from a design value such as a cross-sectional dimension of the liquid flow path. A recording head can be manufactured. By mounting such a liquid jet recording head, it is possible to greatly contribute to the improvement and stabilization of the printing quality of the liquid jet recording apparatus.

[Brief description of drawings]

1A and 1B show a liquid jet recording head according to an embodiment, wherein FIG. 1A is a perspective view thereof, FIG. 1B is a sectional view taken along line AA of FIG. 1A, and FIG. It is a partial elevation view which shows a part of a).

FIG. 2 is a perspective view showing a first step of a method of manufacturing the liquid jet recording head of FIG.

FIG. 3 is a perspective view showing a second step of the method of manufacturing the liquid jet recording head of FIG.

4A and 4B show a third step of the method of manufacturing the liquid jet recording head of FIG. 1, wherein FIG. 4A is a perspective view of the liquid jet recording head, and FIG. It is a perspective view showing a place.

5 is a perspective view showing a fourth step of the method of manufacturing the liquid jet recording head of FIG.

6A and 6B show a liquid jet recording head according to a conventional example, FIG. 6A is a perspective view thereof, and FIG. 6B is a partial sectional view taken along the line BB of FIG.

7A and 7B show a liquid jet recording head according to another conventional example, in which FIG. 7A is a perspective view thereof, and FIG. 7B is a partial elevational view showing a part thereof.

[Explanation of symbols]

 10 Substrate 11 Discharge Energy Generation Element 20 Nozzle Layer 21 Liquid Flow Path 21a Communication Port 22 Discharge Port 30 Common Liquid Chamber Layer 31 Common Liquid Chamber 40 Lid

Claims (3)

[Claims] 1. A first photosensitive resin layer is laminated on a substrate having discharge energy generating means, a liquid flow path is patterned on the first photosensitive resin layer by photolithography, and then a second photosensitive resin is formed. In the photolithography for stacking layers, patterning a common liquid chamber on the second photosensitive resin layer by photolithography, and patterning the common liquid chamber in the atmosphere of the liquid flow path. A method for manufacturing a liquid jet recording head, comprising exposing the second photosensitive resin layer in a state in which a component that prevents curing of the photosensitive resin layer is not included. 2. The method for manufacturing a liquid jet recording head according to claim 1, wherein the air in the liquid flow path is replaced with an inert gas. 3. The method for manufacturing a liquid jet recording head according to claim 2, wherein the inert gas is nitrogen, neon, or argon.