JPH10305582A - Ink-jet type print nozzle head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink-repellent layer which has improved ink repellency and improved abrasion resistance, etc., in a head of an ink-jet type print head nozzle, and improve formation of the nozzle through projection of an excimer laser light. SOLUTION: At least in a peripheral part of a nozzle head, an ink-repellent layer 5 is coated which consists of an organic resin (e.g. polyethersulfone) layer 2 including, for instance, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer at one face of a film-supporting base body 1 of thermosetting polyimide or the like, and an adhesive layer 3 of thermoplastic polyimide or the like at the opposite face. An excimer laser light absorbent (e.g. titaniumdioxide) is added at least to the organic resin layer 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a print nozzle head in an ink jet printer.

[0002]

2. Description of the Related Art In recent years, non-impact recording methods have attracted attention in that noise during recording is extremely low and high-speed recording is possible.

[0003] Among them, an ink jet recording system for recording characters, figures and the like by ejecting liquid ink droplets from a print nozzle head and causing the ink droplets to adhere to recording paper enables high-speed recording and special printing on plain paper. This is an extremely effective recording method capable of recording without performing a fixing process, and various ink jet printers using this ink jet recording method have been proposed and commercialized.

[0004] The ink jet recording system can be roughly classified into three types: a continuous ejection type, an impulse type (on-demand type), and an electrostatic suction type. Among them, the on-demand type is a piezoelectric element or the like only when necessary. Since the ejection energy generating element is driven to eject ink droplets, wasteful consumption of ink is small and the structure is very simple.

However, in any of the ink jet print nozzle heads of any recording systems, if the ink repellency against the ink ejected from the nozzle head is insufficient, the ink is not easily cut and the ink adheres to the peripheral portion of the nozzle head. It is easy to remain. Then, the flight of the ink droplet may be impaired, and recording may not be possible due to troubles such as disturbance of print recording.

In view of the above, a technique has been reported for imparting ink repellency to a peripheral portion of a nozzle head (which is also referred to as a nozzle plate) from which ink of an ink jet type print nozzle head discharges.

For example, in Japanese Patent Application Laid-Open No. 2-187356, a liquid-repellent coating layer, specifically, fluorosilicone is provided as a coating layer on one side of a plate member (for example, polyimide), and a thermosetting It discloses that a nozzle plate comprising an epoxy-based adhesive layer is provided.

In Japanese Patent Application Laid-Open No. 5-330060, fine particles of tetrafluoroethylene (homopolymer) as a fluorine resin are coated on the nozzle head surface with an acrylic resin, a methacrylate resin, a melanin resin, a polyester resin, or a phenol resin. Resin, alkyd resin,
It discloses that any one of the epoxy resins is uniformly mixed to form a water-repellent layer.

[0009]

However, in Japanese Patent Application Laid-Open No. Hei 2-187356, the fluorosilicone coated on the plate member is easily peeled off, and the epoxy resin as an adhesive layer is in a B-stage state before curing. Which is used and stored (moisture,
Changes over time) Since strict attention is required, it is very difficult to use.

In JP-A-5-330060, tetrafluoroethylene is generally merely dispersed in a powder form in the resin, and it is difficult to obtain sufficient ink repellency. This is because tetrafluoroethylene itself does not easily melt and soften, and thus cannot exhibit sufficient ink repellency in this state. In addition, there is a problem that the coated surface is inferior in wear resistance.

On the other hand, in general, as one method of forming a nozzle (ejection port) in a nozzle head, a perforation (penetration) process by excimer laser beam irradiation is performed, and this is exemplified in the above publications. However, in general, fluorine resin has a low absorptivity of laser energy, and therefore has a problem that workability is poor and a discharge port ridge is hardly formed clearly.

The present invention solves the above-mentioned drawbacks, and has excellent ink repellency on the surface of an ink jet type print nozzle head, excellent durability of the ink repellent effect, and excellent wear resistance of the surface of the ink repellent layer. It is an object of the present invention to provide an ink jet print nozzle head that can maintain stable ink droplet ejection for a long time and can have a long life.

[0013]

The present invention employs the following means to solve the above-mentioned problems.

First, as described in claim 1, in the ink jet print nozzle head of the present invention, at least a peripheral portion of the nozzle head is provided on one surface of the support base 1 with a copolymer containing tetrafluoroethylene as one component. And an ink-repellent layer 5 composed of an adhesive layer 3 on the opposite surface.

In order to preferably achieve the nozzle head, the means is achieved by claims 2 to 6.

Furthermore, in order to make the nozzle perforation processing by the excimer laser easier and to make the ridgeline clear,
The means is provided in claim 7. That is, it can be achieved by incorporating an excimer laser light absorber into the organic resin layer 2 containing the copolymer containing tetrafluoroethylene as a component in the first aspect. Hereinafter, the present invention will be described in detail.

[0017]

DETAILED DESCRIPTION OF THE INVENTION An ink jet printer includes:
An ink tank is provided according to the ink color used,
There are a plurality of nozzle heads corresponding to this ink tank. For example, by driving a discharge energy generating element such as a piezoelectric element, each color ink is ejected from a nozzle head and printed on a subject. In the present invention, the support base 1, the organic resin layer 2, and the adhesive layer 3 constitute the ink-repellent layer 5, and the adhesive layer 3 of the layer 5 is adhesively coated on the nozzle head body 6.

First, the support 1 is generally made of a synthetic resin having excellent heat resistance, mechanical strength and chemical resistance. However, among them, the substrate is as thin as possible,
For example, a film having a thickness of 10 to 200 μm may be selected from those exhibiting the above characteristics. Specifically, for example, a whole aromatic polyamide, thermosetting polyamide imide or polyimide, polyether imide, polyether sulfone, polyether ether ketone and the like each film-like material is mentioned, among which thermosetting polyimide film is preferable. Incidentally, the polyimide film is generally prepared by adding an equimolar amount of an aromatic dianhydride such as pyromellitic dianhydride and an aromatic diamine such as 4,4'-diaminodiphenylmethane to an organic polar solvent such as N-methyl. The reaction is carried out at a low temperature in pyrrolidone to form a polyamic acid (polyimide precursor). At this stage, it is cast to a desired thickness, and finally heated at a temperature of 300 ° C. or more to imidize it. A polyimide film can be obtained.

Next, the organic resin layer 2 will be described.

First, the copolymer containing tetrafluoroethylene as one component in the layer can be uniformly dispersed in a molten state in the organic resin layer by selecting the copolymer in particular. Extremely high ink repellency can be provided around the head. Further, since the ink is not separated from the organic resin at all times, the same ink repellency can be maintained for a long time. This characteristic manifestation is due to the fact that the copolymer itself melts and softens, but specific examples of the copolymer include tetrafluoroethylene-hexafluoropropylene copolymer (FEP) and tetrafluoroethylene. An ethylene-perfluoroalkyl vinyl ether copolymer (PFA) is mentioned as a preferable thing. This is because it can be uniformly dissolved and dispersed in the organic resin, and higher ink repellency can be obtained.

The organic resin (matrix resin) for uniformly dispersing the copolymer with tetrafluoroethylene has excellent adhesive strength to the support substrate 1 and heat resistance (preferably 150 ° C. or higher). It is selected from those having excellent chemical resistance and mechanical strength. Examples of such a resin include polyether sulfone, polysulfone, polyphenylene sulfide, polyether ether ketone, polyether imide, and the above-mentioned thermosetting polyamide imide or polyimide. Among them, as the support base, a polyether sulfone is preferably used in addition to the exemplified thermosetting polyimide.

The larger the amount of the copolymer with tetrafluoroethylene to be mixed in the organic resin, the better. However, if it is too large, the uniform mixing property in the organic resin is poor, and the sustainability of the above properties is also lacking. . Considering this point, the mixing ratio is preferably 30 to 95% by weight, preferably 50 to 80% by weight based on the total amount.

When mixing the two, an organic solvent or water may be used in combination for the purpose of dilution or easy handling, but it is preferable to use an organic solvent that dissolves or swells the organic resin. For example, in the case of thermosetting polyimide, N-methylpyrrolidone of polyamic acid as its precursor, an organic solvent such as dimethylacetamide, dimethylformamide, γ-butyl lactone, and in the case of polyether sulfone, the solvent Can be used in combination with methyl isobutyl ketone.

In many cases, the support substrate 1 is coated with the organic resin layer 2 in a liquid state. After the coating, in the case of the polyamide imide or polyimide, about 100 μm is required for removal of the organic solvent and imidization. The temperature is gradually raised between -450 ° C. On the other hand, for other organic resins,
Heat is applied to evaporate off the organic solvent. The thickness coated by this is appropriate, but is generally thinner than the supporting substrate 1 and is about 1 to 10 μm.

Next, the adhesive layer 3 will be described.

The adhesive layer 3 is necessary for bonding and covering the peripheral portion of the nozzle head with the support base 1 having the organic resin layer 2 containing the copolymer containing tetrafluoroethylene as one component as an upper layer. is there. Therefore, it must be firmly bonded to both the support base 1 and the peripheral surface of the nozzle head. At the same time, it is necessary to have excellent heat resistance, chemical resistance, and mechanical properties. In this sense, generally used thermosetting adhesives such as epoxy-based, phenol-based, urethane-based, and acrylic-based adhesives may be used, but these are used for handling in the B-stage state as described above. At the same time, the adhesive strength between the peripheral surface of the nozzle head and the support substrate 1 may not be sufficient, and thermoplastic polyimide is more preferable in this regard.

This thermoplastic polyimide is a resin which melts by heating, that is, a resin having a melting point, unlike the above-mentioned thermosetting polyimide which decomposes without being melted by heating. Those having such properties have, for example, at least one ether bond or carbonyl bond in the main chain of the repeating unit of polyimide. For example, an equimolar amount of pyromellitic dianhydride and 4,4'-bis (3-aminophenoxy) biphenyl are subjected to a polycondensation reaction in an organic polar solvent, and imidization is performed. The polyimide can be separated from the solvent and melt-extruded as a film.

The thickness of the adhesive layer 3 is appropriately determined.
Generally, a thickness of about 1 to 10 μm is sufficient.

The method for coating the ink-repellent layer 5 composed of the support substrate 1, the organic resin layer 2 and the adhesive layer 3 on the periphery of the nozzle head is as follows. 3 may be heat-pressed to the periphery of the head with an adhesive layer 3, or the adhesive may be coated on the periphery of the head first, and then the support substrate 1 An organic resin containing a copolymer containing fluoroethylene as one component may be coated, and the means is not particularly limited. Here, the coating method itself is not limited, and a generally used method, for example, dipping, spraying, spin coating, roll coating, or the like can be used.

Next, claim 7 will be described.

In many cases, the nozzle formation of the ink repellent layer is performed by a perforation process by some means before coating the periphery of the nozzle head. An excimer laser beam irradiation is one of the processing methods, which is preferably used. However, in general, it is difficult to perforate sharply, efficiently, and efficiently with a fluororesin itself. This is because the resin does not absorb light in the ultraviolet wavelength of the excimer laser light in that region. As described above, in the present invention, since the organic resin itself absorbs light by being contained in the organic resin, this facilitates the perforation processing using excimer laser light. Furthermore, in order to improve this, in the present invention, an absorber absorbing the excimer laser light is contained in the organic resin layer 2. Of course, the absorber is contained in one or both of the support substrate 1 and the adhesive layer 3. You may do it.

Examples of the absorbent include organic substances such as metal powder, ceramics, inorganic substances such as titanium dioxide, carbon black, graphite, azo pigments, and phthalocyanine pigments. The mixing amount of these is the same as that of the organic resin layer 2.
Is preferably about 0.01 to 20% by weight based on the weight. This range depends on the type of the absorbent. Further, these absorbents are preferable because they also contribute to improvement of abrasion resistance and the like.

The absorbent is generally a powder,
The shape is not particularly limited. Further, a coupling agent treatment may be used in combination to further improve the dispersibility.

[0034]

The present invention will be described in more detail with reference to the following examples.

(Embodiment 1) First, the entire configuration of the present invention will be described with reference to FIG.

5 shows the entire structure of the ink-repellent layer, which uses a 75 μm film made of the thermosetting polyimide described in the text as a supporting substrate 1 and 2 shows a polyether sulfone resin made of tetrafluoroethylene. An organic resin layer composed of an ethylene-hexafluoropropylene copolymer and titanium dioxide, and numeral 3 represents an adhesive layer composed of a thermoplastic polyimide.

Here, the organic resin layer 2 was formed according to the following recipe.

10% by weight of a polyethersulfone resin, 10% by weight of a tetrafluoroethylene-hexafluoropropylene copolymer and 5% by weight of titanium dioxide are combined with 50% by weight of N-methylpyrrolidone and 25% by weight of methyl isobutyl ketone. And mixed uniformly. After coating the obtained solution on one side of the film by a spray method, first raise the temperature to 60 ° C.
And heated to 380 ° C. for 30 minutes. The organic solvent was also completely evaporated to obtain an organic resin layer 2 of polyethersulfone in which the tetrafluoroethylene-hexafluoropropylene copolymer and titanium dioxide were uniformly dispersed. Its thickness was 5 μm.

The fluororesin copolymer was mixed with polyethersulfone in a molten state. Therefore, the surface was extremely smooth.

The adhesive layer 3 was formed by using a thermoplastic polyimide UPA-N221 manufactured by Ube Industries, Ltd. (a 20% by weight solution of tetrahydrofuran is sold as a varnish), and further adding N-methylpyrrolidone to the adhesive layer 3 times. Diluted into
This was coated on the opposite surface of the thermosetting polyimide support substrate 1 by a spray method. This was heated at 60 ° C. for 5 minutes, at 90 ° C. for 5 minutes, and at 150 ° C. for 5 minutes.
Next, thermocompression bonding (20) to the nozzle head body 6 made of ceramic is performed.
At 0 ° C. for 3 minutes). The thickness of the adhesive layer 3 was 4 μm.

(Embodiment 2) In order to form the nozzle 4 corresponding to the through-hole of the nozzle head body 6 in the ink-repellent layer 5 obtained in the above-mentioned embodiment 1, the position is irradiated with an excimer laser beam to form a hole. processed.

Specifically, a KrF laser (oscillation wavelength 24
8 nm) at an irradiation energy density of 1.2 J / cm ² and processed by being incident from the adhesive layer 3 side.

At this time, in order to remove the processing material scattered by the laser processing from around the nozzle, an assist gas (N ₂ ) was sprayed on the processing portion simultaneously with the laser processing.

It was possible to obtain the penetrating nozzle 4a very quickly and very clean only at the irradiated portion. FIG. 2 shows a state after bonding to the nozzle head main body 6 by thermocompression bonding.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing an ink-repellent layer in Example 1 of the present invention.

FIG. 2 is a side sectional view showing a state of Example 2 of the present invention in which an ink-repellent layer is perforated by irradiation with excimer laser light and then adhered to a nozzle head main body.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Support base 2 Organic resin layer 3 Adhesive layer 4 Nozzle (before penetration) 4a Nozzle (after penetration) 5 Ink-repellent layer 6 Nozzle head main body

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Nobuo Kimura 2-6-80 Shimohanazawa, Yonezawa City, Yamagata Prefecture Inside Yonezawa NEC Corporation (72) Inventor Masatoshi Yasuhara 5-7-1 Shiba, Minato-ku, Tokyo Within NEC Corporation (72) Inventor Hiroshi Tanaka 7546 Yasuda, Kashiwazaki City, Niigata Prefecture Inside Niigata Nippon Electric Co., Ltd. 72) Inventor Kazuto Onjuku 163 Morikawaramachi, Moriyama-shi, Shiga Prefecture Gunze Co., Ltd.

Claims (7)

[Claims] In an ink jet print nozzle head, at least a peripheral portion of the nozzle head is provided with an organic resin layer (2) containing a copolymer containing tetrafluoroethylene as one component on one surface of a support base (1). An ink jet print nozzle head, wherein the opposite surface is covered with an ink repellent layer (5) composed of an adhesive layer (3). 2. An ink jet print nozzle head according to claim 1, wherein said support base is a base made of thermosetting polyimide. 3. The copolymer containing tetrafluoroethylene as one component is a tetrafluoroethylene-hexafluoropropylene copolymer or a tetrafluoroethylene-copolymer.
2. The ink jet print nozzle head according to claim 1, wherein the ink jet print nozzle head is any one of a perfluoroalkyl vinyl ether copolymer. 4. The ink jet print nozzle head according to claim 1, wherein the organic resin is an organic synthetic resin having a heat-resistant temperature of 150 ° C. or higher. 5. The ink jet print nozzle head according to claim 4, wherein the organic synthetic resin is at least one of polyethersulfone, polyamideimide, polyimide, polyetherimide, polysulfone, polyphenylene sulfide, and polyetheretherketone. 6. An ink jet print nozzle head according to claim 1, wherein said adhesive layer (3) is a thermoplastic polyimide. 7. An ink jet print nozzle head, characterized in that at least the organic resin layer (2) according to claim 1 contains an excimer laser light absorber.