JPH068448A - Surface treatment of ink jet recording head - Google Patents

Abstract

PURPOSE:To enable a water repellent film of a fluorine-containing molecule to be attached to a nozzle front plane by a method wherein only a support material is selectively removed by bringing the support front face to which a water repellent agent containing a high polymer molecule containing fluorine is applied into contact with the nozzle front plane having nozzle pore. CONSTITUTION:A nozzle front plane 6 having a nozzle pore 5 is brought into contact with a front plane 10 of a fluorine-containing high molecular film 7, dried by heating, and the nozzle front plane 6 is stuck fast to the front plane 10 of the high molecular film 7. Then, in order to remove the high molecular film 7 stuck close to the nozzle front plane 6 and a needless part 11 of a support material 8, the support material 8, the high molecular film 7, and an ink jet recording head base material 4 are dipped into soluble solvent 12 of the support material 8. Then, when the ink jet recording head base material 4 is taken out from the soluble solvent 12 of the support material 8, the support material 8 is removed from the front plane 13 of the high molecular film 7. Since the nozzle pore 5 is covered with the high molecular film 7, the high molecular film 7 of a part blocking the nozzle pore 5 is removed. Surface treatment of the ink jet recording head is thus completed.

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 ink jet recording head used in an ink jet recording apparatus.

[0002]

2. Description of the Related Art On the front surface of a nozzle having a nozzle hole of an ink jet recording head, if the water repellency is not sufficient, ink dripping may occur during ink ejection, resulting in poor ejection stability and directionality. Then, a method of making a nozzle front surface having a nozzle hole water-repellent is disclosed in JP-A-55-65564. Furthermore, JP-A-63-23906
According to Japanese Patent Laid-Open No. 3 (1993), as one of methods for forming a water-repellent film on a nozzle front surface having a nozzle hole, a surface treatment agent provided on a support is ejected to an ink ejection port of an ink jet recording head. A method of transferring to a surface is shown. More specifically, the surface of the support coated with the surface treatment agent and the ink ejection surface of the ink jet recording head in which the ink ejection ports are formed are brought into close contact with each other and peeled off to remove the surface treatment agent from the ink ejection head of the ink jet recording head. It is transferred to the ink ejection surface where the outlet is formed.

[0003]

However, in the prior art, in the step of transferring the water repellent agent on the support to the nozzle hole surface having nozzle holes, the support and the nozzle hole surface having nozzle holes are drawn. When peeled off, even if the thickness of the water-repellent agent on the support before transfer is uniform, the film thickness of the water-repellent film formed on the nozzle front surface having the nozzle holes is not uniform,
The water repellent film was not partially transferred in the step of separating the support and the nozzle front surface having the nozzle hole, and a defective portion was sometimes formed in the formed water repellent film. In addition, when printing is performed using an ink jet recording head in which a water repellent film is formed on a nozzle front surface having a nozzle hole by a conventional water repellent film transfer method, the ink thickness is not uniform near the nozzle. The ejection direction of the droplets is disturbed, or the ink droplets adhere to the defective portion of the water-repellent film when the ink droplets are ejected and cannot be removed, resulting in ink dripping, which deteriorates the ejection direction and stability of the ink droplets. Furthermore, due to the presence of the water-repellent film defect,
Peeling of the water-repellent film occurs from the defective portion, not only the durability of the water-repellent film is significantly reduced, but the peeled water-repellent film remains on the nozzle surface having the nozzle holes, resulting in a large amount of ink dripping, The problem that ink cannot be ejected has not been solved.

[0004]

The surface treatment method for an ink jet recording head of the present invention is a method for treating a surface of an ink jet recording head, wherein a fluorine-containing polymer film is formed on a nozzle surface having nozzle holes of the ink jet recording head. The support surface coated with a water repellent containing a fluorine-containing polymer is brought into contact with the nozzle front surface having nozzle holes, and only the support is selectively removed by a solvent or heat to selectively repel the fluorine-containing polymer. It is characterized in that the water film is attached to the front surface of the nozzle having the nozzle hole.

[0005]

EXAMPLE 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. Reference numeral 2 is an ink flow path, and 3 is an ink ejection nozzle.

FIG. 2 shows the surface treatment method of the present invention.
FIG. 2 is an enlarged view of the vicinity of the ink discharge nozzle 3 of FIG. 1 that has been subjected to water repellent treatment with a fluorine-containing polymer film. A fluorine-containing polymer film 7 is formed on the nozzle front surface 6 having the nozzle holes 5 of the inkjet recording head substrate 4.

(Embodiment 1) FIG. 3 is a diagram showing a first surface treatment step of a surface treatment method for an ink jet recording head according to the present invention. FIG. 3A is a cross-sectional view of the ink ejection nozzle portion of the inkjet recording head substrate, showing an inkjet recording head substrate 4, nozzle holes 5, and a nozzle front plane 6 having nozzle holes 5. FIG. 3 b shows the surface 9 of the support 8.
FIG. 3 is a diagram in which a fluorine-containing polymer film 7 and a front surface 10 of the fluorine-containing polymer film 7 are formed on the top. FIG. 3 c shows that the nozzle surface 6 having the nozzle holes 5 and the surface 10 of the fluorine-containing polymer film 7 are brought into contact with each other and heated and dried to form the nozzle surface 6 having the nozzle holes 5 and the fluorine-containing polymer film 7. It is the figure which made the front plane 10 closely contact. FIG. 3d shows a fluorine-containing polymer film 7 and a support 8 which are in close contact with a nozzle front surface 6 having nozzle holes 5.
It is the figure which removed the unnecessary part 11 of. 3e shows the support 8
FIG. 6 is a diagram in which the support 8, the fluoropolymer film 7, and the inkjet recording head substrate 4 are dipped in the soluble solvent 12 of FIG. FIG. 3 f is a view of the inkjet recording head substrate 4 taken out of the soluble solvent 12 of the support 8 and shows the support 8
Are removed from the front surface 13 of the fluorine-containing polymer film 7. Next, since the nozzle hole 5 is closed with the fluorine-containing polymer film 7, the portion containing the nozzle hole 5 of the fluorine-containing polymer film 7 is removed. FIG. 3g is a diagram in which the fluorine-containing polymer film blocking the nozzle holes 5 is removed and the surface treatment of the inkjet recording head is completed. Specifically, by irradiating laser light or ultraviolet light with a portion other than the nozzle hole 5 shielded by a metal plate or the like, or by pushing a pin having the same diameter as the nozzle hole, the portion that closes the nozzle hole 5 is included. The fluoropolymer film was removed.

Now, the fluorine-containing polymer film 7 and the support 8 of the present invention will be described. The fluorine-containing polymer film 7 is attached to the surface 9 of the support 8 by appropriately selecting from a depping method, a transfer method, a water surface spreading film transfer, spray coating, cast coating, blade coating and the like. The fluoropolymer film 7 is preferably a solvent-soluble fluoropolymer and is amorphous. For example, a solvent-soluble fluorine-containing polymer such as polydiperfluoroalkyl fumarate, Teflon AF (registered trademark of DuPont), Cytop (registered trademark of Asahi Glass Co., Ltd.), or diperfluoroalkyl fumarate and styrene Alternating copolymers of fluorine-containing ethylene and vinyl ester or analogs thereof such as alternating copolymers, alternating copolymers of ethylene trifluoride chloride and vinyl ether, alternating copolymers of tetrafluoroethylene and vinyl ester Or derivatives are preferably used. As the solvent, a fluorinated liquid such as Fluorinert (registered trademark of 3M Company), Galden, (registered trademark of Montefluos Company), trifluoromethylbenzene, or hydrochlorofluorocarbon is preferably used. The concentration of the fluoropolymer is 0.01 to 7
It is in the range of% by weight. The material of the support 8 is selected under the condition that it is soluble in a liquid inert to the ink jet recording head substrate 4.

A specific example of the first embodiment will be described.

Polysulfone as the base material 4 of the ink jet recording head, CYTOP as the fluorine-containing polymer film 7,
A water-soluble polyvinyl alcohol film was used as the support 8, and water was used as the soluble solvent 12 of the support 8. First, a method for forming the fluorine-containing polymer film 7 on the surface of the support 8 will be described. A fluorinate solution in which Cytop was dissolved was applied to the surface of the polyvinyl alcohol film by a depping method or a spin coating method. After standing for about 5 minutes, the nozzle surface 5 having the nozzle holes 5 and the fluorine-containing polymer film 7 formed on the surface of the polyvinyl alcohol film are brought into contact with each other and dried by heating at about 150 ° C. 7 and the nozzle front surface 6 having the nozzle hole 5 were brought into close contact with each other. The fluorine-containing polymer film and the support which have the nozzle holes 5 and protrude from the nozzle surface 6 are cut, and the fluorine-containing polymer film and the support are provided only on the nozzle surface 6 having the nozzle holes 5. I was in a state of riding. The polyvinyl alcohol film was dissolved by immersing the inkjet recording head substrate 4 in water. When the surface of the fluoropolymer film was observed with a microscope, no partial defect in the fluoropolymer film was found. Further, the film thickness of the fluorine-containing polymer film was extremely uniform on the front surface of the nozzle having the nozzle holes. Finally, the fluorine-containing polymer film in the portion that closes the nozzle hole 5 was photolyzed by irradiation with ultraviolet light to secure a nozzle hole for ink ejection.

Next, a printing test was carried out by mounting the ink jet recording head having the surface treatment of the present invention on a recording apparatus. As a result, troubles such as dot omission and print disturbance did not occur, and good water repellent treatment was performed. It was confirmed that
Next, the ink jet recording head was immersed in the dye ink and held at 70 ° C. for 5 days, and then the same printing test was conducted. The printing was the same as the initial characteristics, and the ink repellency effect was sufficient. A rubbing test using silicone rubber while injecting dye ink showed that the contact angle with water on the nozzle surface with nozzle holes was 100 degrees or more even after the test, and the water-repellent effect hardly deteriorated and the print quality was long. It was possible to achieve a high inkjet recording head.

(Embodiment 2) FIG. 4 is a second surface treatment step showing a surface treatment method for an ink jet recording head according to the present invention. FIG. 4A is a cross-sectional view of the ink discharge nozzle portion of the ink jet recording head substrate, showing the ink jet recording head substrate 4, the nozzle holes 5, and the nozzle front plane 6 having the nozzle holes 5. FIG. 4 b shows the surface 9 of the support 13.
FIG. 3 is a diagram in which a fluorine-containing polymer film 7 and a front surface 10 of the fluorine-containing polymer film 7 are formed on the top. FIG. 4c is a diagram in which the nozzle front surface 6 having the nozzle holes 5 and the front surface 10 of the fluorine-containing polymer film 7 are in contact with each other. FIG. 4d shows that the support 13 is dissolved in the process of heating and drying the fluorine-containing polymer film 7,
It shows that the fluorine-containing polymer film 7 is flowing down from the surface 14. FIG. 4 e shows a nozzle front plane 6 with nozzle holes 5.
Indicates that only the fluorine-containing polymer film 7 is in close contact. FIG. 4f is a diagram in which the unnecessary portion 15 of the fluorine-containing polymer film 7 is removed. FIG. 4g is a diagram showing that the surface treatment of the inkjet recording head is completed by removing the fluorine-containing polymer film that has blocked the nozzle holes 5. Specifically, the portion other than the nozzle hole 5 is irradiated with laser light or ultraviolet light in a state where the metal plate is shielded from light, or a pin having the same diameter as the nozzle hole is pushed in, so that the fluorine-containing portion of the portion that closes the nozzle hole 5 is blocked. The polymer membrane was decomposed and removed.

Specific materials for the support 13 used in the present invention will be described below. The support 13 dissolves in the heating and drying step of the fluorine-containing polymer film 7 or after drying, and the temperature is not a temperature at which the inkjet recording head substrate 4 and the fluorine-containing polymer film 7 melt or significantly deform. I won't. Specifically, there is no problem as long as it is a solid such as paraffin wax at room temperature and has a melting point of 100 ° C. or less. However, the melting point of 100 ° C. or lower does not limit the support used in the present invention, and is not limited as long as the ink jet recording head substrate and the fluorine-containing polymer film do not dissolve or significantly deform.

A specific example of the second embodiment will be described.

Polysulfone as the base material 4 of the ink jet recording head, CYTOP as the fluorine-containing polymer film 7,
Paraffin wax having a melting point of about 60 ° C. was used as the support 13. First, a method for forming the fluorine-containing polymer film 7 on the surface of the support 8 will be described. A fluorinate solution in which Cytop was dissolved was applied to the surface of the polyvinyl alcohol film by a depping method or a spin coating method. After being left for about 5 minutes, the nozzle surface 6 having the nozzle holes 5 of the polysulfone inkjet recording head substrate 4 and the fluorine-containing polymer film 7 formed on the surface of the paraffin wax are brought into contact with each other to about 150 ° C. After heating and drying, the fluorine-containing polymer film 7 was brought into close contact with the nozzle surface 6 having the nozzle holes 5. The paraffin wax used for the support 13 was dissolved during the heating and drying of the fluoropolymer film 7 and was removed from the surface of the fluoropolymer film. A portion of the fluorine-containing polymer film protruding from the nozzle surface 5 having the nozzle hole 5 is cut to form a nozzle surface 6 having the nozzle hole 5.
The fluorine-containing polymer film was placed only on the top. When the surface of the fluoropolymer film was observed with a microscope, no partial defect in the fluoropolymer film was found. Further, the film thickness of the fluorine-containing polymer film was extremely uniform on the front surface of the nozzle having the nozzle holes. Finally, the fluorine-containing polymer film in the portion that closes the nozzle hole 5 was photolyzed by irradiation with ultraviolet light to secure a nozzle hole for ink ejection.

Next, a printing test was carried out by mounting the ink jet recording head, which has been subjected to the surface treatment of the present invention, on a recording apparatus. As a result, troubles such as dot omission and print disturbance did not occur, and good water repellency was obtained. It was confirmed that processing was done. Next, the ink jet recording head was immersed in the dye ink and held at 70 ° C. for 5 days, and then the same printing test was conducted. The printing was the same as the initial characteristics, and the ink repellency effect was sufficient. A rubbing test with silicone rubber was performed while injecting the dye ink. After the test, the contact angle with water on the nozzle surface having the nozzle holes was 100 degrees or more, and the water repellent effect was not deteriorated over a long period of time. An inkjet recording head with high print quality was achieved.

[0017]

As described above, according to the present invention, the fluorine-containing polymer film of the fluorine-containing polymer is uniformly transferred onto the nozzle surface having the nozzle holes without causing a partial defect. It Since the fluorine-containing polymer film does not cause partial defects, the adhesion of the fluorine-containing polymer film is extremely excellent.
The durability time of the inkjet recording head is significantly extended.

Further, according to the present invention, in the step of transferring the fluorine-containing polymer film on the support to the nozzle surface having the nozzle holes, it is not always necessary to apply pressure to the support and the nozzle surface having the nozzle holes. I have found Support,
If the fluoropolymer film is heated and dried while the fluoropolymer film and the nozzle surface with nozzle holes overlap, the fluoropolymer film will adhere to the nozzle surface with sufficient nozzle holes. To do. Further, the film thickness of the fluorine-containing polymer film was more uniform when pressure was not applied to the support and the front surface of the nozzle having the nozzle holes. This effect is obtained by bringing the fluorine-containing polymer film into close contact with the nozzle surface having nozzle holes,
It is realized only by performing the step of dissolving the support having the fluorine-containing polymer film on the surface, which is a major feature of the present invention. In the conventional transfer method, pressure is applied to the support and the nozzle surface having the nozzle holes to bring the fluoropolymer film into close contact with the nozzle surface having the nozzle holes, and before the fluoropolymer film is dried. Since the fluoropolymer film was transferred by peeling off the body, it was not possible to obtain a uniform film thickness as in the present invention.

[Brief description of drawings]

FIG. 1 is a diagram showing an outline of an inkjet recording head.

FIG. 2 is an enlarged view of the vicinity of an ink ejection nozzle hole of an inkjet recording head that has been subjected to the surface treatment of the present invention.

FIG. 3 is a diagram showing a first embodiment of the surface treatment process of the present invention.

FIG. 4 is a diagram showing a second embodiment of the surface treatment process of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pressure chamber 2 Ink flow path 3 Ink ejection nozzle 4 Head base material 5 Nozzle hole 6 Nozzle front plane having nozzle holes 7 Fluorine-containing polymer film 8 Support

Claims (1)

[Claims] 1. A method for treating a surface of an inkjet recording head, which comprises forming a fluorine-containing polymer film on a front surface of a nozzle having a nozzle hole of the inkjet recording head, wherein the surface of the support is coated with a water repellent agent containing the fluorine-containing polymer. A feature is that a water-repellent film of a fluorine-containing polymer is adhered to a nozzle front surface having a nozzle hole by contacting with a nozzle front surface having a nozzle hole and selectively removing only a support by a solvent or heat. A method for surface treatment of an inkjet recording head.