JPH05229118A - INKJET RECORDING HEAD AND METHOD OF MANUFACTURING THE SAME - Google Patents

Abstract

(57) [Abstract] [Purpose] An ink jet recording head capable of easily ejecting bubbles generated in an ink flow path by a simple operation and having a highly effective effect, and an extremely simple manufacturing method thereof. Is in the place of providing. [Structure] An oxide layer 31 is formed on the surface of the ink flow path 2 in contact with the ink and the bonding surface between the first substrate 4 and the second substrate 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording head used in an ink jet recording apparatus and a method for manufacturing the same.

[0002]

2. Description of the Related Art In an ink jet recording head using a water-based ink, when the ink in the ink flow channel is poorly wet, bubbles are left in the flow channel during ink filling or bubbles generated in the flow channel. However, it is difficult to discharge even if the discharge operation is performed, and recording may not be possible due to troubles such as missing dots and print disturbance.

To improve the wettability of the water-based ink, a hydrophilic treatment is applied to the surface of the ink flow path.
24957, it has been proposed to perform corona discharge treatment, flame treatment, plasma treatment (physical treatment), sulfonation treatment (chemical treatment), etc. in the flow path of a resin inkjet recording head. In addition, Japanese Patent Publication No. 2-54784
Also in the resin ink jet recording head,
A method (aging treatment) is disclosed in which an aqueous dye solution is brought into contact with an ink flow path at a high temperature to make it hydrophilic.

[0004]

However, since the above-mentioned hydrophilic treatment of the resin surface according to the prior art is not long-lasting, it is left for a long time without being filled with ink in the ink ejection device. However, there is a problem that the hydrophilic effect is lost.

In some cases, chromium, ITO, silicon or the like is used as a component for the ink jet recording head as a material having excellent ink resistance. However, depending on the above-mentioned prior art, all of them are subjected to a highly durable hydrophilic treatment. It was difficult to apply.

The present invention is intended to solve the above problems, and an object thereof is to allow an ink jet recording head to easily discharge bubbles generated in an ink flow path by a simple operation, and An object of the present invention is to provide an ink jet recording head having high effect lasting and an extremely simple manufacturing method thereof.

[0007]

The present invention is characterized in that, in an ink jet recording head, an oxide layer is formed at least on the surface of a flow path in contact with ink.

Further, according to the present invention, in an ink jet recording head in which an ink flow path is formed by adhering a first substrate and a second substrate in which a pattern groove for an ink flow path is formed, at least the flow path surface in contact with ink It is characterized in that an oxide layer is formed on.

Further, the manufacturing method is characterized in that after the oxide layer is formed on the pattern groove for the ink flow path and the bonding surface, the first substrate and the second substrate are bonded.

The oxide layer of the present invention is formed by fine particles of a metal oxide such as aluminum, titanium and zirconium, a non-metal oxide such as silicon, and a complex compound thereof. Usually, oxide fine particles are mixed with water, methanol,
Disperse in an electrolyte such as ethanol or isopropanol,
It can be a stable sol. For these, it is necessary to use an organic solvent that does not violate the base material of the ink jet recording head as a main dispersion solvent.

The oxide layer is formed on the first substrate and the second substrate by a simple method in which the oxide fine particle dispersed sol is applied by spin coating or dipping into the dispersed sol, and then dried at a high temperature. it can.

[0012]

After the sol in which the oxide fine particles are dispersed is applied to the surface of the ink flow path and the dispersion solvent is dried, the oxide fine particles are fixed and a hydrophilic oxide layer is formed. The surface of the oxide fine particles has a large specific surface area and is active, and since it has many hydroxyl groups, it is very hydrophilic.

[0013]

EXAMPLES The present invention will be described in more detail based on examples.

FIG. 1 is a schematic view of an ink jet recording head. Reference numeral 1 denotes a pressure chamber, which is a portion for obtaining a pressure for ejecting ink by a PZT element, a heating element, or the like. Two
Is an ink flow path, and 3 is an ink ejection nozzle. FIG. 2 is an enlarged view of a cross section taken along the line AA ′ in FIG. Reference numeral 4 is a first substrate on which a pattern groove for an ink flow path is formed.
Reference numeral 5 denotes a second substrate, in which the pattern groove for the ink flow path is not formed in the figure, but it may be formed. The ink flow path is formed by bonding the first substrate and the second substrate.

Example 1 The average particle size of the silica fine particles was 0.01 μm.

As shown in FIG. 3, the first and second substrates made of polysulfone resin, in which the pattern grooves for ink flow paths are formed, are washed and dried, and then the sol of oxide fine particles having the above composition is dispersed at 3000 rpm / min. It was spin coated. 10
After drying at 0 ° C. for 1 hour, a solvent cement prepared by dissolving the same polysulfone resin in triethylene glycol monomethyl ether was applied to the bonded portion and bonded at a pressure of 1 kgf / cm ² to manufacture a substrate for an inkjet recording head.

Example 2 Alumina sol-520 (manufactured by Nissan Chemical Co., Ltd.) 5 wt% methanol 85 wt% pure water 10 wt% Alumina fine particles have an average particle diameter of 0.02 μm and a concentration of about 1
It was wt%.

As shown in FIG. 3, a polycarbonate resin first substrate and a second substrate, each having a pattern groove for an ink flow path formed thereon, are washed and dried, and then an oxide fine particle-dispersed sol having the above composition is added at 3000 rpm / min. It was spin coated. 8
After drying at 0 ° C. for 1 hour, an inkjet recording head substrate was manufactured in the same manner as in Example 1 below.

Example 3 Zirconia sol 0.2 wt% Methanol 99.8 wt% The average particle size of the zirconia sol was 0.07 μm.

As shown in FIG. 4, a pattern groove for ink flow path is formed on the glass plate in the same manner as the first substrate on which pattern groove for ink flow path is formed of acrylic photocurable resin. The two substrates were washed and dried, then dipped in the oxide fine particle-dispersed sol having the above composition and pulled up at a constant velocity of 10 cm / sec to apply the sol. After drying at 80 ° C. for 1 hour, the first substrate and the second substrate were thermocompression bonded at 150 ° C. for 1 hour at a pressure of 1 kgf / cm ² to manufacture an inkjet recording head substrate.

Comparative Example 1 An inkjet recording head substrate was manufactured in the same manner as in Example 1 except that the oxide fine particle-dispersed sol was not spin-coated on the first substrate and the second substrate.

Comparative Example 2 An ink jet recording head substrate was manufactured in the same manner as in Example 2 except that the oxide fine particle-dispersed sol was not spin-coated on the first substrate and the second substrate.

Comparative Example 3 An ink jet recording head substrate was manufactured in the same manner as in Example 3 except that the first substrate and the second substrate were not dipped in the oxide fine particle dispersed sol.

Comparative Example 4 A substrate for an ink jet recording head obtained in the same manner as in Comparative Example 3 was immersed in an aging treatment liquid having the following composition for 24 hours at a temperature of 60 ° C. for hydrophilic treatment.

Aging treatment liquid: Pure water 94 wt% N-methyl-2-pyrrolidone 4 wt% Dye C.I. I. Acid Red 35 2 wt% Using the substrates of Examples 1, 2 and 3 and Comparative Examples 1, 2, 3 and 4, a PZT element and a circuit for driving the PZT element were connected to the pressure chamber portion, and an ink jet recording head was formed. Manufactured,
The following bubble discharge test was conducted using the ink having the following composition.

Ink: Food black 2 2 wt% Glycerin 5 wt% Ethanol 5 wt% Pure water 88 wt% Bubble discharge test: 5 ml / min by a pump from the ejection nozzle side of the ink jet recording head mounted on the recording apparatus.
Fill the ink by the method of sucking the ink. Printing is performed every 10 seconds of suction time, and the time until the bubbles remaining in the flow path are completely discharged and troubles such as missing dots and print disturbance disappear are measured, and the bubble discharging property is measured according to the following criteria. judge.

Completely disappears in 30 seconds or less ∘ It does not disappear in 30 seconds ・ ・ ・ × The above-mentioned bubble discharge test is performed again immediately after head production and after removing ink from the inkjet recording head and leaving at 70 ° C. for 5 days. It was The results are shown in Table 1.

[0028]

[Table 1]

As is clear from Table 1, the heads using the substrates of Comparative Examples 1 to 3 were not able to completely discharge the air bubbles in the flow path immediately after manufacturing, and normal printing was impossible. Further, although the head using the substrate subjected to the hydrophilization treatment by aging of Comparative Example 4 was good immediately after the production, when the ink was extracted and left at 70 ° C. for 5 days, the hydrophilic effect was deteriorated and the air bubble discharging property was poor. Normal printing is no longer possible.

On the other hand, the heads using the substrates of Examples 1, 2 and 3 were heated at 70 ° C. immediately after manufacturing and at 5 ° C.
Since the hydrophilic effect was not deteriorated at all even after being left for a day, it was possible to easily discharge the air bubbles in the flow path and to perform normal printing.

[0031]

As described above, according to the present invention, it is possible to provide an ink jet recording head capable of easily ejecting the air bubbles generated in the ink flow path of the ink jet recording head by a simple operation. In addition to simplifying the device for reducing the cost of the recording device, the ink consumed for discharging bubbles can be significantly saved.

Further, since the hydrophilic treatment according to the present invention is very excellent in its durability, it can be transported and stored in a state where the flow path of the ink jet recording head is empty, so that the transportation cost can be reduced and The life of the recording head can be extended.

Further, the method of manufacturing the ink jet recording head of the present invention can be hydrophilized by an extremely simple apparatus and process, so that it is safe in manufacturing and the cost can be greatly reduced, and its effect is great.

[Brief description of drawings]

FIG. 1 is a schematic view of an ink ejection device.

FIG. 2 is an enlarged view of a cross section taken along the line A-A ′ in FIG.

FIG. 3 is an enlarged view of a cross section of an ink discharge device having an oxide layer according to the present invention.

FIG. 4 is an enlarged view of a cross section of an ink ejection device having an oxide layer of the present invention.

[Explanation of symbols]

 1 Pressure Chamber 2 Ink Flow Path 3 Ink Ejection Nozzle 4 First Substrate 5 Second Substrate 31 Oxide Layer 32 Adhesive Surface between First and Second Substrates

Claims (3)

[Claims] 1. An ink jet recording head, wherein an oxide layer is formed on at least a surface of a flow path which is in contact with ink. 2. An ink jet recording head having an ink flow path formed by bonding a first substrate having a pattern groove for the ink flow path and a second substrate, and a flow path surface in contact with ink and a first substrate. An inkjet recording head, wherein an oxide layer is formed on an adhesive surface between a substrate and a second substrate. 3. An ink jet recording head in which an ink flow path is formed by adhering a first substrate and a second substrate on which a pattern groove for ink flow path is formed, to an ink flow path pattern groove and an adhesion surface. A method for manufacturing an ink jet recording head, which comprises manufacturing by forming a layer of oxide and then bonding a first substrate and a second substrate.