JPH05116324A - Ink jet discharge nozzle plate and its manufacture - Google Patents

Abstract

PURPOSE:To provide an ink jet discharge nozzle plate, in which a chemisorption monomolecular film containing fluorine is formed only in the necessary part of the surface, and the manufacture of the nozzle plate. CONSTITUTION:A carbon fluoride chemisorption monomolecular film with a very thin film thickness having liquid-repellent properties equal to those of fluorine polymer coating film conventionally known heretofore is uniformly formed only in the necessary part of the surfaces of nozzle plates by a process for forming a metal thin film in the junction of the nozzle plates 102, 103 to a body member 101, etc., through vapor deposition, sputtering, etc., by a process for forming a carbon fluoride chemisorption monomolecular film all over the surfaces of these nozzle plates and by a process for separating the metal thin film formed in a part of the surfaces of these nozzle plates through an etchant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inkjet ejection nozzle plate such as an ink ejection nozzle or an air ejection nozzle in a recording head of an inkjet recording apparatus.

[0002]

2. Description of the Related Art Conventionally, a nozzle plate for ink jet discharge of this kind is required to have a liquid-repellent surface in order to stably generate and fly ink droplets. A liquid-repellent coating film is formed.

As a conventional liquid repellent coating method for ink jet ejection nozzles, a method of applying a fluorine-based polymer such as FEP or a method of treating a chemisorption monomolecular film containing fluorine is known.

[0004]

However, the method of applying the fluorine-based polymer in the prior art is very troublesome because it is performed by spraying or brushing, and it has been a main factor of cost increase. Further, it is difficult to control the film thickness and make the coating film uniform, and the liquid repellency, that is, the holding state of the meniscus at the ink ejection nozzles varies in the same head of the inkjet recording apparatus and between the heads. Further, in a head having an air nozzle, the thickness of the air layer varies,
It was the main cause of variations in head characteristics. Further, particularly when the liquid repellent surface of the nozzle is exposed to the outside, there is a problem that the polymer coating film itself is soft and thus is easily scratched, and the bond adhesion to the nozzle base material is weak and peeling is likely to occur.

On the other hand, in the chemical adsorption monomolecular film treatment method containing fluorine, it is possible to impart liquid repellency to the entire nozzle surface by simply immersing the nozzle in an organic solvent type treatment liquid for a certain period of time. It has an advantage that the cost can be reduced by the production. Also, because it is a monomolecular film by chemical adsorption,
The coating formed has the advantage of being very uniform and strong. However, since this method is a method of dipping in an organic solvent-based liquid, a liquid-repellent film is formed even in a portion where liquid repellency is a problem, for example, a joint portion where the adhesive force of the adhesive is impaired. However, there was a problem that sufficient adhesion could not be obtained.

The present invention solves the above-mentioned conventional problems, and an object of the present invention is to provide a nozzle plate for ink-jet discharge in which a chemisorption monomolecular film containing fluorine is formed only on a necessary portion of the surface.

Another object of the present invention is to provide a method for easily manufacturing the above nozzle plate for ink jet ejection.

[0008]

In order to achieve the above object, a method for manufacturing an ink jet discharge nozzle plate according to the present invention comprises a step of forming a mask film on a part of the surface of the nozzle plate, and The method includes a step of forming a chemisorption monomolecular film containing fluorine on the entire surface, and a step of peeling off the mask film formed on a part of the surface of the nozzle plate together with the monomolecular film as an upper layer.

More specifically, for example, a step of forming a metal film by PVD such as vapor deposition or sputtering on a part of the surface of an ink jet discharge nozzle plate, and a chemisorption monomolecule containing fluorine on the entire surface of the nozzle plate. The method includes a step of forming a film and a step of peeling a metal film formed on a part of the surface of the nozzle plate with an etching solution or the like.

[0010]

Therefore, according to the present invention, for example, in a method of forming a metal film on a portion of the surface of a nozzle plate which does not require liquid repellency, when the nozzle plate is subjected to chemical adsorption monomolecular film treatment containing fluorine, The liquid-repellent monolayer is formed on the metal film in the portion where the metal film is formed, and is formed directly on the nozzle substrate in the portion where the metal film is not formed. Next, when this nozzle plate is immersed in an etching solution and ultrasonic waves are applied, the etching solution easily passes between the monomolecular film layers, and as a result, the metal film of the lower layer is attacked and the metal film is removed together with the monomolecular film layer of the upper layer. It is peeled off. Further, in the portion of the nozzle substrate where the monomolecular film is directly formed, since the lower layer is not attacked by the etching liquid, the monomolecular film having liquid repellency is formed as it is. As a result, it is possible to uniformly form a carbon fluoride-based monomolecular film having an extremely thin film thickness at the nanometer level and having liquid repellency equivalent to that of a fluorine-based polymer coating film represented by FEP, only on a desired portion of the nozzle surface. Furthermore, since these monomolecular films are chemically bonded to the surface of the nozzle substrate, they are very strong.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of a static electricity control type inkjet recording apparatus to which the present invention is applied. In FIG. 1, 101 is a body member, 102 is an air nozzle plate, 1
Reference numeral 03 is an ink nozzle plate. An air nozzle plate 1 made of an insulating material and joined to the tip of the outer wall of the body member 101.
The No. 02 air nozzle 108 is formed so as to face the ink nozzle 107 of the ink nozzle plate 103 also made of an insulating material. The pressurized air generated by the air supply source 112 flows into the air chamber 104 from the air supply passage 110, passes through the air layer 105 formed by the air nozzle plate 102 and the ink nozzle plate 103, and the air nozzle 108.
More leaked. Since this air flow is rapidly changing in the vicinity of the air nozzle 108, a sharp pressure gradient is generated in the space from the ink nozzle 107 to the air nozzle 108. On the other hand, the ink chamber 106 adjacent to the ink nozzle 107 communicates with the ink supply source 113 via the ink supply path 111, and the ink in the ink supply source 113 is applied with a constant air pressure from the air supply source 112. .. The signal source 115 includes an electrode 109 provided near the outlet of the air nozzle 108 and the ink chamber 106 of the ink nozzle 107.
The ink is oily with a high electric resistance and is connected to the electrode 114 provided on the periphery facing the electrode 10.
9 and a potential difference is generated between the ink held in the openings of the ink nozzles 107. Due to the electrostatic force due to this potential difference, the meniscus of the ink generated at the opening of the ink nozzle 107 is extended toward the air nozzle 108. Further, since a rapid pressure gradient is generated in the space from the ink nozzle 107 to the air nozzle 108, when the ink meniscus generated at the opening of the ink nozzle 107 is stretched by a certain amount or more, the ink meniscus is accelerated by the pressure gradient and flies from the air nozzle 108. ..

Next, FIG. 2 shows an enlarged cross section in the vicinity of the nozzle of the ink jet head. As shown in FIG. 2, in order to stabilize the formation of the meniscus of the ink nozzle 107 to stabilize the droplet generation, the air nozzle plate 1 is also used.
In order to prevent the surface of the air nozzle plate 102 and the ink nozzle plate 103 and the nozzle wall surface from being soiled by ink or paper dust, a carbon fluoride chemical adsorption monomolecular film 116 having excellent oil repellency and antifouling property is formed. Has been formed.

(Embodiment 1) FIG. 3 shows an air nozzle plate 102.
FIG. 3 is a plan view of the ink from the back side, that is, the ink nozzle plate 103 side. Air nozzle plate 1 made of glass after nozzle processing
No. 02 is prepared and washed with an organic solvent such as acetone or trichloroethane, and then a portion excluding the joint portion 117 with the body member 101 is masked with a metal pattern, and aluminum is vapor-deposited. After the vapor deposition is completed, a metal thin film of aluminum is formed only on the joint portion 117. Next, a substance containing a fluorocarbon group and a chlorosilane group (a fluorocarbon surfactant), for example, CF ₃ (CF ₂ ) ₇ (CH ₂ ) ₂ SiCl
₃ at a concentration of about 1% by weight, a non-aqueous solvent, specifically 8
A solution prepared by dissolving 0 wt% n-hexadecane (toluene, xylene, dicyclohexyl, etc.), 12 wt% carbon tetrachloride and 8 wt% chloroform in a solvent was prepared, and the air nozzle plate 102 was kept for 2 hours. Immerse about. The oxide is exposed on the glass surface and the aluminum vapor deposition film surface of the air nozzle plate 102, and the oxide surface contains a large number of hydroxyl groups that have reacted with moisture in the air. Therefore, the SiCl group contained in the substance containing the linear carbon fluoride group and the chlorosilane group reacts with the hydroxyl group to cause a dehydrochlorination reaction, and a bond represented by the chemical formula (Formula 1) is formed over the entire nozzle surface. To be done.

[0014]

[Chemical 1]

FIG. 4A is an enlarged view of the air nozzle plate 102 after the monomolecular film containing fluorine is formed by the above process. The monomolecular film 116 is formed on the surface of the aluminum metal film 118 where it exists, and the monomolecular film 1 is directly formed on the surface of the air nozzle plate 102 where there is no metal film 118.
16 are formed. FIG. 5 is a detailed view of the portion A in FIG. The state is shown in which the monomolecular film 116 containing fluorine is chemically bonded to the surface of the air nozzle plate 102, and a film thickness of about 15 Å is formed. At this time, the monomolecular film 116 is extremely strongly chemically bonded.

Next, the air nozzle plate 102 may be provided with an etching solution, for example, a mixed solution of an aqueous solution of iron (II) chloride and hydrochloric acid (in addition, a mixed solution of phosphoric acid, nitric acid, acetic acid and water, dilute hydrochloric acid, an aqueous solution of sodium hydroxide, etc.). .) For about 1 minute to peel off the metal film. A mixed solution of iron (II) chloride aqueous solution and hydrochloric acid had high permeability to the monomolecular film 116 and could be peeled off in a very short time. Then, wash thoroughly with water.

A state in which the above steps are completed is shown in FIG. The etching liquid penetrates between the monomolecular films 116 and attacks the underlying metal film 118, and only the portion where the metal film 118 was formed is peeled off together with the monomolecular film 116. On the other hand, in the portion where the metal film 118 is not formed, the monomolecular film 116 is not peeled off and is still formed by a strong chemical bond.

An attempt was made to actually use the air nozzle plate 102 having the monomolecular film 116 formed thereon. The result is that the liquid repellency to ink, that is, the effect of preventing wetting is comparable to that of the above-mentioned fluorine-based polymer-coated nozzle, and the surface is rubbed with plastic or paper, and is scratched, peeled or worn. There was nothing to do. Furthermore, the adhesive strength of the adhesive was good at the joint where the monomolecular film was peeled off, and sufficient sealing was possible. In addition, in this embodiment, since the mask is used during the vapor deposition of the metal film, there is mass productivity, and the metal film pattern can be easily formed as long as the mask can be formed. Even if it is complicated, the purpose can be easily achieved.

A liquid repellent film can be formed on the ink nozzle plate 103 by the same processing method. The portion of the ink nozzle plate 103 where the formation of the carbon fluoride-based chemical adsorption monomolecular film 116 is not desirable is the portion that faces the joint with the body member 101 and the ink chamber 106, and is the entire back surface. Therefore, aluminum deposition is performed on the entire back surface of the ink nozzle plate 103 to form a metal film, and the same process is performed.

(Embodiment 2) Next, a description will be given of the case where silicon, which is hydrophilic but has a relatively small proportion of hydroxyl groups, is used as the nozzle material.

A nozzle plate made of silicon which has been subjected to nozzle processing is prepared, and as in the case of Example 1, a portion where an oil repellent coating film is required later is masked with a metal pattern and a metal film of aluminum is formed by vapor deposition. Substances containing a plurality of trichlorosilyl groups (eg, SiCl ₄ , SiHCl ₃ , S
iH ₂ Cl ₂ or _{Cl- (SiCl 2 O) n -Si} ,
Cl ₃ (n is an integer). In particular, if SiCl ₄ is used, since the molecule is small and the activity for the hydroxyl group is large, the effect of uniformly making the nozzle surface hydrophilic is large. ) Is mixed for about 30 minutes in a non-aqueous solution (for example, a solution of 1% by weight dissolved in a chloroform solvent). As shown in FIG. 6A, since there is a relatively small amount of hydrophilic OH groups on the surface of the nozzle plate 201, a dehydrochlorination reaction occurs on the surface and a chlorosilane monomolecular film of a substance containing a plurality of trichlorosilyl groups. Is formed.

For example, when SiCl ₄ is used as the substance containing a plurality of trichlorosilyl groups, a small amount of hydrophilic OH groups are exposed on the nozzle surface, and thus a dehydrochlorination reaction occurs on the surface, and (Chemical Formula 2) , The molecule is fixed to the surface via the —SiO— bond.

[0023]

[Chemical 2]

Thereafter, by washing with a non-aqueous solvent such as chloroform, and further washing with water to cause a reaction, SiCl ₄ molecules which have not reacted with the base material are removed,
A siloxane monomolecular film 202 containing a plurality of silanol groups represented by the chemical formula (Chemical Formula 3) as shown in FIG. 6B is obtained on the nozzle surface.

[0025]

[Chemical 3]

Since the monomolecular film 202 obtained here is completely bonded to the nozzle through the chemical bond of —SiO—, it is not peeled off. Further, the obtained monomolecular film had many Si—OH bonds on the surface, and about three times as many as the initial hydroxyl groups were generated.

Then, as in Example 1, a solution containing a substance containing a linear carbon fluoride group and a chlorosilane group (a fluorocarbon surfactant) in a non-aqueous solvent at a predetermined concentration, for example, CF ₃ (CF ₂ ) ₇ (CF ₂ ) ₂ SiCl
80 wt% n dissolved at a concentration of about 1 wt% using ₃
-Hexadecane, 12 wt% carbon tetrachloride, 8 wt% chloroform solution was prepared, in which Si-OH was added to the surface.
The nozzle formed with the monomolecular film 202 having many bonds is immersed for about 1 hour. Then, the bond of (Chemical Formula 1) is generated on the nozzle surface as in Example 1, and the monomolecular film 203 containing fluorine is chemically bonded to the lower siloxane monomolecular film as shown in FIG. 6C. Thus, it was possible to form a film having a thickness of about 15 Å over the entire nozzle surface. Next, this nozzle plate is immersed in an etching solution which is a mixed solution of an aqueous solution of iron (II) chloride and hydrochloric acid for about 30 seconds in the same manner as in Example 1 to remove the metal film. Then, wash thoroughly with water.

The fluorine-containing monomolecular film 203 ensures liquid repellency and antifouling properties equivalent to those of a fluorine-based polymer film, does not peel even after a peeling test, and has high abrasion resistance. Was also realized.

In each of the above-mentioned embodiments, aluminum is used as the metal for vapor deposition because it is easy to peel and inexpensive, but other metals such as zinc and nickel may be used.

In each of the above-mentioned examples, CF ₃ (CF ₂ ) ₇ (CH ₂ ) ₂ SiCl was used as the fluorocarbon surfactant.
_{Although 3} was used, if a C = C or C≡C group is added to or incorporated in the alkyl chain portion, crosslinking can be carried out by irradiation of about 5 megarads after formation of the monomolecular film, so that the hardness of the monomolecular film is further improved. It is also possible.

Instead of forming a metal film on the nozzle plate, an organic polymer film such as polyvinyl alcohol which is insoluble in an organic solvent but is soluble in an organic solvent is formed to form a carbon fluoride monomolecular film. After the formation, the organic polymer film may be washed with water to separate the carbon fluoride-based monomolecular film above it.

[0032]

As described above, according to the present invention, a chemisorption monomolecular film containing fluorine is formed only on a necessary portion of the surface of an ink jet discharge nozzle plate. For example, a joint portion with a body member or an ink chamber is formed. By not forming such a monomolecular film on the surface facing to, it is possible to enhance the adhesive force of the adhesive and prevent the fluidity of the ink from being impaired.

The method for manufacturing an ink jet discharge nozzle plate according to the present invention comprises a step of forming a mask film on a part of the surface of the nozzle plate and a chemisorption monomolecular film containing fluorine on the entire surface of the nozzle plate. A nozzle having a step of forming and a step of peeling off the mask film formed on a part of the surface of the nozzle plate together with the monolayer film of the upper layer, and the nozzle having the monolayer film only on a necessary part of the surface. The plate can be easily manufactured.

Further, a step of forming a metal film by PVD such as vapor deposition or sputtering on a part of the surface of the nozzle plate of the present invention, a step of forming a chemisorption monomolecular film containing fluorine on the entire surface of the nozzle plate, According to the manufacturing method having the step of peeling the metal film formed on a part of the nozzle plate surface with the etching solution, only the portion of the nozzle plate surface where liquid repellency is required is equivalent to the conventional fluorine-based polymer coating film. It is possible to uniformly form a carbon fluoride monomolecular film having liquid repellency, and the formed liquid repellent film is an extremely thin monolayer having a thickness of nanometer level. The thickness of the air layer can be kept constant, the nozzle diameter is not deformed and the nozzles are not clogged, and a large amount of processing can be performed at one time, greatly reducing production costs. It has very beneficial effects such as can be.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view showing an embodiment of a static control type ink jet recording apparatus to which a nozzle plate according to the present invention is applied.

FIG. 2 is a partially enlarged sectional view of a nozzle plate in the same device.

FIG. 3 is a bottom view of an air nozzle plate in the same device.

FIG. 4A is a partially enlarged cross-sectional view after forming a liquid repellent film according to the first embodiment of the present invention. FIG. 4B is a partially enlarged cross-sectional view after peeling a metal film according to the first embodiment of the present invention.

FIG. 5 is an enlarged conceptual view of a nozzle surface for explaining the first embodiment of the present invention.

6A, 6B, and 6C are enlarged conceptual views of a nozzle surface for explaining a second embodiment of the present invention.

[Explanation of symbols]

 101 Body Member 102 Air Nozzle Plate 103 Ink Nozzle Plate 104 Air Chamber 105 Air Layer 106 Ink Chamber 107 Ink Nozzle 108 Air Nozzle 109 Electrode 110 Air Supply Channel 111 Ink Supply Channel 112 Air Supply Source 113 Ink Supply Source 114 Electrode 115 Signal Source 116 Fluoridation Carbon-based chemical adsorption monomolecular film 117 Bonding part 118 Metal film 201 Nozzle plate 202 Siloxane monomolecular film 203 Carbon fluoride monomolecular film

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Gen Oda, 3-10-1 Higashisanda, Tama-ku, Kawasaki City, Kanagawa Prefecture Matsushita Giken Co., Ltd. (72) Inventor, Koichi Saito, East Tama-ku, Kawasaki City, Kanagawa Prefecture 3-10-1, Mita Matsushita Giken Co., Ltd.

Claims (5)

[Claims] 1. A nozzle plate for ink jet discharge, wherein a chemisorption monomolecular film containing fluorine is formed only on a necessary portion of the surface. 2. A step of forming a mask film on a part of the surface of the inkjet discharge nozzle plate, and a step of forming a chemisorption monomolecular film containing fluorine on the entire surface of the nozzle plate.
A method of manufacturing an inkjet discharge nozzle plate, which comprises a step of peeling a mask film formed on a part of the surface of the nozzle plate together with an upper monolayer film thereof. 3. The method for manufacturing an inkjet discharge nozzle plate according to claim 2, wherein the mask film on the surface of the nozzle plate is a metal film. 4. The method for manufacturing a nozzle plate for ink jet ejection according to claim 3, wherein the metal film on the surface of the nozzle plate is formed by PVD. 5. The method for manufacturing an inkjet discharge nozzle plate according to claim 3, wherein the metal film on the nozzle surface is removed by an etching solution.