JPH06171094A - Ink jet recording head and manufacturing method thereof - Google Patents

Abstract

(57) [Summary] [Structure] In an inkjet recording head used in an inkjet recording apparatus, an oxide fine particle layer is formed on a nozzle plate surface from which ink is ejected, and a fluorine-containing silicon coupling layer is further formed thereon. It is characterized by being The organosol having the organic solvent in which the oxide fine particles are dispersed as the main dispersion solvent is applied to the nozzle surface, heated to the temperature of dephysically adsorbed water of the oxide fine particles or higher, and the fluorine-containing silicon coupling agent solution is applied thereon. It is formed by heating above the boiling point of the solvent. [Effect] The nozzle surface of the inkjet recording head can be subjected to water-repellent and oil-repellent treatment with excellent characteristics, and an inkjet recording head with high printing quality can be provided. Further, since the surface treatment according to the present invention is extremely excellent in its durability, the life of the recording head can be extended.

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.

[0002]

2. Description of the Related Art Inkjet recording heads are made of glass,
Materials such as metal and resin are used. However, in the ink jet recording head, if the water and oil repellency of the nozzle surface is insufficient, ink droplets will adhere, impairing the straightness of the ejected ink droplets and making recording impossible due to problems such as print disturbance. there were.

Therefore, it has been shown that the surface of a nozzle plate from which ink is ejected is treated to be water and oil repellent in order to eliminate the adhesion of ink.
5), eutectoid plating, plasma polymerization (JP-A-60-183)
161) and the like, there is provided a method in which fluorine-containing resin particles are attached to the nozzle surface to make it water and oil repellent. Further, a method of fluorine-containing silicon coupling treatment (JP-A-56-89569) and a method of applying a solvent-soluble fluorine-containing resin to form a thin film (JP-A-3-13273) are also provided.

[0004]

However, the ink has been improved in response to the demands for high definition of printing quality, high contrast, and multicolor, and an additive for ensuring long-term stability of the ink is also required. became. The water-repellent and oil-repellent treatment according to the above-mentioned conventional technique has insufficient initial characteristics, and when it is immersed in ink for a long time, the treated layer is peeled off or ink is adsorbed, resulting in remarkable deterioration of characteristics.

The present invention has been made to solve the above-mentioned problems, and the water-repellent and oil-repellent treatment with excellent characteristics is performed on the surface of the nozzle plate of the ink jet recording head, and further, the effect is excellent in durability and printing is performed for a long period of time. It is an object of the present invention to provide a high quality ink jet recording head and an easy manufacturing method thereof.

[0006]

In the ink jet recording head used for an ink jet recording apparatus, the above-mentioned object is to form an oxide fine particle layer on the surface of a nozzle plate from which ink is ejected, and further to form a fluorine-containing silicon coupling layer thereon. Is achieved by forming The inkjet recording head can be manufactured by using at least the following steps.

A) A step of applying an organosol whose main dispersion solvent is an organic solvent in which fine oxide particles are dispersed, onto the surface of a nozzle plate from which ink is ejected.

B) Dephysiological adsorption of oxide fine particles A step of heating above the water temperature to fix the oxide fine particle layer.

C) A step of applying a fluorine-containing silicon coupling agent solution on the oxide fine particle layer.

D) A step of heating to above the boiling point of the solvent to fix the fluorine-containing silicon coupling layer.

[0011]

[Function] For inks having high penetrability and high storage stability, the method of adhering fluorine-containing resin particles to the nozzle plate surface and the method of forming a fluorine-containing resin thin film are Is extremely small, the adhesion is insufficient and the ink penetrates into the interface to cause peeling.
Further, the method of fluorine-containing silicon coupling treatment,
Although it is strongly bonded to the reactive group of the base material by a chemical bond, the density of the reactive group is low, so the bond density is low, and the ink is adsorbed to the portion not subjected to the fluorine-containing silicon coupling treatment and deteriorates. The initial high water / oil repellency is brought about by the fluorine-containing silicon coupling agent which is not chemically bonded and is only attached, and is not durable.

When the oxide fine particle-dispersed sol is applied to the surface of the nozzle plate and heated to a temperature higher than the temperature of dephysically adsorbed water of the oxide fine particles, the oxide fine particle layer is firmly fixed. Unlike the fluorine-containing resin particles, the oxide fine particles have a remarkably large surface energy, and thus are particularly excellent in adhesiveness with metals and inorganic materials. Since the silica fine particles are eroded by the ink and are eluted, the alumina and zirconia fine particles having high ink resistance are general-purpose and preferable. The surface of the oxide fine particle layer is active and has many hydroxyl groups. Therefore, the fluorine-containing silicon coupling agent can be chemically bonded at a high density. When heated to the boiling point of the solvent or higher, the unreacted chemical bond of the fluorine-containing silicon coupling agent just attached is promoted, and the fluorine-containing silicon coupling layer can be firmly fixed. Since the treatment layer is not peeled off or ink is not adsorbed, the initial characteristics are maintained.

Various types of fluorine-containing silicon coupling agents are commercially available, and it is comparative that it is possible to secure excellent water and oil repellency in the initial stage by using those having low surface energy and high steric hindrance. It is easy.

[0014]

【Example】

(Embodiment 1) FIG. 1 is a sectional view schematically showing an example of an ink jet recording head. 1 is a pressure chamber, PZ
This is a portion for obtaining a pressure for ejecting ink by the T element or the heating element. Reference numeral 3 is an ink ejection nozzle. Reference numeral 4 is a first substrate on which a pattern groove for an ink flow path is formed. Reference numeral 5 is a second substrate, and an ink flow path is formed by bonding the two. 2 is a nozzle plate.

FIG. 2 is a schematic sectional view showing the steps of water repellent treatment of the nozzle plate surface. (A) is an enlarged view of the vicinity of the nozzle of the nickel nozzle plate before treatment. The diameter of the nozzle is several tens of μm.

(B) shows a state where the oxide fine particle layer is fixed on the surface of the nozzle plate. An alumina sol in which alumina particles were dispersed in a solvent containing ethanol as a main component was used as the sol on the surface of which the oxide particles were dispersed. An appropriate value can be selected for the size and concentration of the alumina fine particles, but here, the average particle diameter of the alumina is 0.05 μm,
An example of an alumina sol having a concentration of 1 wt% will be described. Alumina fine particles can be obtained by hydrolyzing an aluminum alkoxide. Alumina sol 5
It is also possible to use a non-spherical fine powder such as 20 (manufactured by Nissan Chemical Co., Ltd.). The back surface of the nozzle plate or the inside of the nozzle was protected with a mask tape or a photoresist, and alumina sol was applied to the surface of the nozzle plate by dipping. The alumina fine particle layer could be formed with a thickness of about 0.2 μm. After removing the protective layer, heat treatment was performed at 300 ° C. for 1 hour. The temperature of the dephysically adsorbed water of alumina fine particles by differential thermal analysis is 130 ° C. It can be seen that the contact angle with water is as high as about 10 degrees and shows a high hydrophilicity and has a high density of hydroxyl groups.

(C) shows a state in which the fluorine-containing silicon coupling layer is fixed on the oxide fine particle layer. 1H, 1 which is a fluorine-containing silicon coupling agent in a fluorine-based solvent
10% of H, 2H, 2H-PERFLUORODECYLTRICHLOROSILANE was dissolved and applied to the surface of the nozzle plate. The boiling point of the fluorine-based solvent is 180 ° C. The sample heat-treated at each heat treatment temperature for 1 hour was dipped in a dye ink having high permeability,
Table 1 shows the contact angles with the ink before and after holding at 70 ° C for 5 days.
Shown in. It was found that a sufficient water / oil repellency effect was obtained by the heat treatment at 200 ° C. or higher.

[0018]

[Table 1]

Initially, the ink was repelled inside the nozzle without the alumina fine particle layer, but due to the ink aging, good wettability was exhibited. For trial, apply a solution of fluorine-containing silicon coupling agent on a nickel plate, and
When a sample heat-treated at 0 ° C. for 1 hour was prepared,
The initial contact angle with the ink was 70 degrees, but it was 10 degrees after the ink immersion.

After applying the fluorine-containing silicon coupling agent solution, an ink jet recording head manufactured by using a nozzle plate which was heat-treated at 300 ° C. for 1 hour was mounted on a recording apparatus and a printing test was conducted. No trouble occurred, and high-definition and high-contrast printing became possible. A rubbing test using silicone rubber while injecting ink showed that the contact angle with the ink was 60 degrees or more even after rubbing 10,000 times, and the water and oil repellency effect was hardly deteriorated, and inkjet recording with high print quality for a long time I was able to achieve the head.

Example 2 A sol in which zirconia fine particles were dispersed was applied to the surface of a nozzle plate made of stainless steel (SUS316-L). An appropriate value can be selected for the size and concentration of the zirconia fine particles, but here, the average particle diameter is 0.02 μm.
Of spherical zirconia particles were prepared by hydrolyzing alkoxide, and the concentration was 0.5 wt% in methanol.
Dispersed. The back surface of the nozzle plate or the inside of the nozzle was protected with a mask tape or a photoresist, and the zirconia sol was applied to the surface of the nozzle plate by spin coating. The zirconia fine particle layer could be formed with a thickness of about 0.1 μm. After removing the protective layer, heat treatment was performed at each heat treatment temperature for 1 hour. The temperature of the dephysically adsorbed water of the zirconia fine particles by differential thermal analysis is 170 ° C. It can be seen that the contact angle with water shows a high hydrophilicity of about 10 degrees regardless of the heat treatment temperature, and has a high density of hydroxyl groups.

10% of fluorine-containing silicon coupling agent KP-801M (manufactured by Shin-Etsu Chemical Co., Ltd.) in a fluorine-based solvent.
Dissolve, apply on the nozzle plate surface, and at 120 ℃ 1
Heat treated for hours. The boiling point of the fluorine-based solvent is 100 ° C. A sample heat-treated for 1 hour at each heat-treatment temperature after applying zirconia sol was dipped in a pigment ink containing a surfactant and a stabilizer, and the contact angle before and after the ink was kept at 70 ° C. for 5 days was shown. 2 shows. It was found that sufficient adhesion strength was obtained by heat treatment at 200 ° C. or higher.

[0023]

[Table 2]

After the zirconia sol was applied, an ink jet recording head manufactured by using a nozzle plate heat-treated at 300 ° C. for 1 hour was mounted on a recording apparatus and a printing test was conducted, and no trouble such as print disturbance was found. Printing with high contrast and high weather resistance is now possible. A rubbing test with silicone rubber was performed while injecting ink, and the contact angle with ink was 60 even after rubbing 10,000 times.
As a result, an ink jet recording head with high printing quality could be achieved for a long period of time with almost no deterioration in water and oil repellency.

Example 3 A sol in which fine zirconia particles were dispersed was applied to the surface of a nozzle plate made of stainless steel (SUS316-L). An appropriate value can be selected for the size and concentration of the zirconia fine particles, but here, the average particle diameter is 0.06 μm.
Zirconia sol NZS-30A (manufactured by Nissan Kagaku Co., Ltd.) was dispersed in methanol at a concentration of 2 wt%. The back surface of the nozzle plate or the inside of the nozzle was protected with a mask tape or a photoresist, and the zirconia sol was applied to the surface of the nozzle plate by spin coating. The zirconia fine particle layer could be formed with a thickness of about 0.3 μm. After removing the protective layer, heat treatment was performed at 200 ° C. for 1 hour. The dephysically adsorbed water temperature of the zirconia fine particles by differential thermal analysis is 120 ° C. The contact angle with water is about 15 degrees, which shows high hydrophilicity, and it is understood that the polymer has a high density of hydroxyl groups.

1H, 1H, 2H, 2H-PERFLUOROOCTYLTRIETHOXYSIL which is a fluorine-containing solvent and a fluorine-containing silicon coupling agent
Dissolve 3% of ANE and apply it to the surface of the nozzle plate.
It heat-processed at 50 degreeC for 1 hour. The boiling point of the fluorinated solvent is 1
It is 00 ° C. Dip in ink containing color dye, and
When kept at 0 ° C. for 5 days, it was found that a contact angle with the ink of 60 ° or more was obtained, and sufficient water / oil repellency effect and adhesion strength were obtained.

When an ink jet recording head manufactured by using this nozzle plate was attached to a recording apparatus and a printing test was conducted, no trouble such as print disturbance was observed.
Vivid color printing is now possible. When a rubbing test with silicone rubber was performed while injecting ink, 1000
The contact angle with ink is 60 degrees or more even after rubbing 0 times,
An ink jet recording head with high printing quality could be achieved for a long period of time with almost no deterioration in water and oil repellency.

[0028]

As described above, according to the present invention, it is possible to provide an ink jet recording head having high printing quality by subjecting the nozzle plate surface to the water and oil repellent treatment having excellent characteristics in the ink jet recording head. Further, since the surface treatment according to the present invention is extremely excellent in its durability, the life of the recording head can be extended.

Further, according to the method of manufacturing the ink jet recording head of the present invention, since the water and oil repellent treatment can be performed by an extremely simple apparatus and process, it is safe in manufacturing and the cost can be drastically reduced. Is big.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of an inkjet recording head according to a first exemplary embodiment.

FIG. 2 is a cross-sectional view that schematically shows the process of water and oil repellency treatment on the surface of the nozzle plate in the first embodiment.

[Explanation of symbols]

 1 Pressure Chamber 2 Nozzle Plate 3 Ink Ejection Nozzle 4 First Substrate 5 Second Substrate 21 Oxide Fine Particle Layer 22 Fluorine-Containing Silicon Coupling Layer

Claims (3)

[Claims] 1. In an inkjet recording head used in an inkjet recording apparatus, an oxide fine particle layer is formed on a surface of a nozzle plate from which ink is ejected, and a fluorine-containing silicon coupling layer is further formed thereon. Inkjet recording head. 2. The ink jet recording head according to claim 1, wherein the nozzle plate used in the ink jet recording apparatus is made of metal, and the oxide fine particle layer formed on the surface of the nozzle plate is made of alumina or zirconia. 3. Use of at least the following steps in the production of an ink jet recording head in which an oxide fine particle layer is formed on the surface of a nozzle plate from which ink is ejected, and a fluorine-containing silicon coupling layer is further formed thereon. A method of manufacturing an inkjet recording head, comprising: a) A step of applying an organosol whose main dispersion solvent is an organic solvent in which fine oxide particles are dispersed, onto the surface of a nozzle plate from which ink is ejected. b) A step of fixing the oxide fine particle layer by heating above the dephysisorption water temperature of the oxide fine particles. c) A step of applying a fluorine-containing silicon coupling agent solution on the oxide fine particle layer. d) A step of heating to above the boiling point of the solvent to fix the fluorine-containing silicon coupling layer.