JP2003127384A - Method for manufacturing ink jet head and ink jet printer having the head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing an ink jet head of high printing quality which is excellent in ink resistance and rubbing resistance properties, and maintains water and oil repellent properties stably for a long time. SOLUTION: The degree of cleanliness of a nozzle surface of the ink jet head can be effectively enhanced by irradiating the nozzle plate 2 surface of the ink jet head with ultraviolet rays 11 having a wavelength of less than 300 nm prior to application of water and oil repellent film. Then, the adhesion force between the nozzle surface and the water and oil repellent film 12 is enhanced by depositing the water and oil repellent film 12 more than 20 nm on the nozzle plate 2 surface to provide durable printing quality.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an inkjet head used in an inkjet recording apparatus and an inkjet printer having the head obtained by the manufacturing method.

[0002]

2. Description of the Related Art Since an ink jet head uses water-based or oil-based ink, if the water-repellent and oil-repellent properties of the nozzle surface are insufficient, the ink tends to adhere. Therefore, the straightness of the ejected ink may be impaired, and the characters may be unreadable due to troubles such as print disturbance.

The ink jet head is made of, for example, silicon, glass, metal, resin or the like as a constituent material. Since these constituent materials have the property of being easily wetted by the ink, the surface of the nozzle from which the ink is ejected is subjected to a water and oil repellent treatment. JP-A-3-43065, Japanese Patent Laid-Open No. Hei 4
A fluorine-containing organic compound as disclosed in Japanese Patent Application Laid-Open No. 505895 has been proposed.

The nozzle surface of the ink jet head is regularly rubbed with rubber in order to remove ink and paper dust adhered during printing. By this operation, the water and oil repellent film is aggregated around the nozzle hole. To achieve this, Japanese Patent Laid-Open No. 9-23
As disclosed in Japanese Patent No. 9991, there has been proposed a manufacturing method in which a water and oil repellent film is irradiated with ultraviolet rays to cure the water and oil repellent film and prevent aggregation of the water and oil repellent film.

[0005]

However, the above-mentioned conventional techniques have the following problems. An inkjet printer having an inkjet head regularly rubs with rubber to remove paper dust and ink droplets attached to the nozzle surface. Further, the printing paper may come into contact with the nozzle surface during printing or when the printing paper is inserted into the printer.

Under these circumstances, the water- and oil-repellent film, which has a weak adhesion to the nozzle surface, is peeled off from the nozzle surface, the water- and oil-repellency is lowered, the straightness of the ink is impaired, and the print quality is deteriorated. However, there was a problem that it became difficult to read the characters.

The present invention solves the above problems, and an object of the present invention is to provide a method for producing an ink jet head having excellent ink resistance and abrasion resistance and high printing quality.

[0008]

The method for producing an ink jet head of the present invention is a method for producing an ink jet head in which a water and oil repellent film is laminated on a nozzle surface from which ink is ejected, and the nozzle surface is treated before the water and oil repellent film is processed. It is characterized in that it is irradiated with ultraviolet rays. In addition, the wavelength of the ultraviolet rays,
It is characterized by being 300 nm or less. Further, a water / oil repellent film having a thickness of 20 nm is formed on the surface of the nozzle by a vacuum deposition method.
It is characterized in that the layers are stacked as described above.

An ink jet printer using the ink jet head obtained by the above manufacturing method is also featured.

According to the above method, the cleanliness of the nozzle surface of the ink jet head before the water and oil repellent film treatment can be effectively enhanced, and the adhesion between the nozzle surface of the ink jet head and the water and oil repellent film is improved. effective.

In the present invention, the energy of ultraviolet rays applied to the nozzle surface of the ink jet head is 300.
When it is nm, it is about 100 kcal / mol. On the other hand, C, which is the main bond of organic substances contaminating the nozzle surface
-C dissociation energy is 83 kcal / mol, C-H is 98 kcal / mol, and C-O is 84 kcal / mol.
Therefore, the bond of the organic substance can be cut by the irradiation of ultraviolet rays. Since the energy of ultraviolet rays increases as the wavelength decreases, ultraviolet rays of 300 nm or less are optimal.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an example of an inkjet head. This inkjet head is a face inkjet type and is driven by an electrostatic system. The inkjet head 1 of FIG. 1 has a three-layer structure in which a cavity plate 3 is sandwiched, a nozzle plate 2 is laminated on the upper side, and a glass substrate 3 is laminated on the lower side.

The cavity plate 3 is, for example, a silicon substrate, and the surface of the cavity plate 3 has an ink chamber 7 whose bottom plate functions as the vibrating plate 6, and an ink supply port 8 provided at the rear of the ink chamber 7. An ink reservoir 9 for supplying ink to the ink chamber 7 is formed by etching.

The nozzle plate 2 bonded to the upper side of the cavity plate 3 is, for example, a silicon substrate like the cavity plate 3. In the nozzle plate 2,
Each of the ink chambers 7 is attached to the part that defines the upper surface of the ink chamber 7.
Is formed with a plurality of nozzle holes 5.

The glass substrate 4 bonded to the lower side of the cavity plate 3 is a borosilicate glass substrate having a thermal expansion coefficient close to that of silicon. In the glass substrate 4, the individual electrodes 10 are formed on the portions facing the respective vibrating plates 6.

The water-repellent and oil-repellent film formed by the vacuum deposition method of the ink jet head manufacturing method of the present invention is the nozzle plate 2 described above.
Is to be formed against. The water-repellent and oil-repellent film is formed by this vacuum deposition method by joining the glass substrate 4, the cavity plate 3 and the nozzle plate 2 to each other,
This is applied to a substrate having a three-layer structure. A chip obtained by cutting the substrate on which this water and oil repellent film is deposited with a slicer is shown in FIG.
The inkjet head shown in FIG.

Next, the method of manufacturing the ink jet head of the present invention will be described in detail with reference to FIG. FIG. 2 is a schematic cross-sectional view of a step of irradiating the nozzle plate 2 of FIG. 1 with ultraviolet rays and a step of forming a water / oil repellent film.

First, the substrate processed into the three-layer structure is fixed to a dedicated jig, and the nozzle plate 2 is combined with the ultraviolet lamp in an ultraviolet irradiation device equipped with an ultraviolet lamp having a wavelength of 300 nm or less. Set to face each other.

After that, the nozzle plate 2 having the nozzle holes 5 shown in FIG. 2A is uniformly irradiated with ultraviolet rays 11 having a wavelength of 300 nm or less. At this time, it is also effective to provide the ultraviolet irradiation device with a mechanism for placing the substrate processed into the three-layer structure on a disk-shaped plate and rotating the disk-shaped plate at a constant speed so that the ultraviolet rays 11 can be uniformly irradiated. Is.

After irradiating with the ultraviolet rays 11, the jig fixing the substrate processed into the three-layer structure was taken out from the ultraviolet irradiating device, the temperature of the jig surface was measured, and the surface temperature of the jig was 30. Let stand naturally until the temperature reaches below ℃. After the surface temperature of the jig reaches 30 ° C. or lower, the jig is set in a vacuum vapor deposition apparatus, and a fluorine-containing silane coupling compound “Paraque Coat” manufactured by Tokyo Product Development Laboratory
2 is vapor-deposited on the nozzle plate 2 by a vacuum vapor deposition method as shown in FIG. 2B, and a water- and oil-repellent film 12 is laminated to a thickness of 20 nm or more.

In the ink jet head 1 manufactured by the manufacturing method of the present invention, the water resistance and oil repellency film 12 formed on the nozzle plate 2 was tested for ink resistance and abrasion resistance.

In the test, a container containing a certain amount of ink was irradiated with ultraviolet rays for 10 minutes, 20 minutes, and 6 minutes before the water- and oil-repellent film treatment.
The ink jet head 1 set to 0 minutes is fixed so that the surface of the nozzle plate 2 may come into contact with the liquid, and the ink jet head 1 is left standing at 70 ° C. for 3 days to perform an ink resistance test. Then, rub the surface of the nozzle plate 2 with rubber in a certain direction 3000 times,
Further, the end surface was bent so that the printing paper was in contact with the nozzle surface, and the carriage of the printer was reciprocated 10 times in 70 seconds to test the abrasion resistance. The inkjet head 1 as a test object is continuously tested for ink contact with the surface of the nozzle plate 2, rubbing with rubber, and rubbing with printing paper, and printing is performed by a printer after each test. Was judged according to the following criteria.

Table 1 shows the test results. ◎: Water and oil repellency on the nozzle surface is secured, and ink droplets are not deflected on the printing paper ○: Water droplets and oil repellency on the nozzle surface are secured, but ink droplets are deflected on the printing paper X: The water and oil repellency of the nozzle surface was not ensured, and the flight curve of ink droplets was confirmed on the printing paper, making it impossible to read the characters.

[0024]

[Table 1]

In this way, the irradiation time of the ultraviolet rays 11 is set to 60
In addition, the ink jet head having the water and oil repellent film 12 vacuum-deposited had the best print quality.

In the ink jet head for which the irradiation time of the ultraviolet ray 11 was 60 minutes, the same rubbing of the nozzle surface with rubber as in the above test was added 10,000 times, and the printing quality was confirmed. As a result, the water and oil repellency of the nozzle surface was secured. And
In addition, no flight bending of ink droplets was observed when printed, and good printing quality was maintained.

The present embodiment describes a part of the present invention. Even if other fluorine-based water and oil repellents or silicone water and oil repellents are used, the concentration of the water and oil repellents is also increased. The same effect was exhibited even when the values were different.

In addition to the vapor deposition method, the water- and oil-repellent material can be formed by a spray method using a liquid in which the water- and oil-repellent material is dissolved,
The dipping method had the same effect.

Further, even when the structure of the ink jet head uses a head having nozzle holes in the direction perpendicular to the flow path, the same effect is obtained.

[0030]

As described above, according to the present invention, the surface of the nozzle plate 2 of the inkjet head is irradiated with the ultraviolet rays 11 having a wavelength of 300 nm or less before the water-repellent and oil-repellent film treatment. The cleanliness can be effectively increased, and thereafter, the water- and oil-repellent film 12 having a thickness of 20 nm or more is formed on the surface of the nozzle plate 2 to improve the adhesive force between the nozzle surface and the water- and oil-repellent film 12, thereby achieving durable printing. It had the effect of improving quality.

Further, it is possible to obtain an ink jet head having the above-mentioned excellent effects.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of an inkjet head to which the present invention is applied.

FIG. 2 is a schematic cross-sectional view of each step of a nozzle plate to which the present invention is applied.

[Explanation of symbols]

1 inkjet head 2 nozzle plate 3 cavity plate 4 glass substrates 5 nozzle holes 6 diaphragm 7 ink chamber 8 ink supply port 9 ink reservoir 10 individual electrodes 11 UV 12 Water and oil repellent film

Claims (4)

[Claims] 1. A method of manufacturing an ink jet head comprising a water and oil repellent film laminated on a nozzle surface from which ink is ejected.
A method for manufacturing an inkjet head, which comprises irradiating the nozzle surface with ultraviolet rays before the water- and oil-repellent film treatment. 2. The method for manufacturing an inkjet head according to claim 1, wherein the wavelength of the ultraviolet rays is 300 nm or less. 3. The method for manufacturing an ink jet head according to claim 1, wherein the water and oil repellent film is formed to a thickness of 20 nm or more by a vacuum vapor deposition method. 4. An ink jet printer having an ink jet head obtained by the manufacturing method according to claim 1.