KR20130108337A - Nozzle printing device and maintenance method therefor - Google Patents

Abstract

The nozzle printing apparatus of this invention is equipped with the nozzle which discharges the ink of the liquid columnar of a predetermined flow volume, and the removal apparatus which removes the ink adhering to the front-end | tip of a nozzle by making the absorbing member which absorbs ink close to the front-end | tip of a nozzle. .

Description

NOZZLE PRINTING DEVICE AND MAINTENANCE METHOD THEREFOR}

The present invention relates to a nozzle printing apparatus and a maintenance method thereof.

The nozzle printing apparatus is one of devices for applying ink to a predetermined position of an object (coated object) such as a substrate. The nozzle printing apparatus includes a nozzle for discharging ink of a liquid column. By discharging ink from the nozzle, the object can be applied onto the object in a predetermined pattern by relatively moving the nozzle and the object disposed below the nozzle. By using such a nozzle printing apparatus, for example, a plurality of organic EL (Electro Luminescence) elements serving as pixels of a display apparatus can be finely formed at predetermined positions on a substrate.

The nozzle printing apparatus continues to discharge the ink on the liquid column when the ink is applied to the object. However, it is not necessary to continue to discharge ink until the ink is not applied to the object. For example, after the application of ink to the object is completed, the ejection of the ink may be stopped while the object is replaced. When the replacement of the object is completed, discharge of ink is started again, and ink is applied to the object.

Fig. 2 is a diagram schematically showing the state of the nozzle and the ink when the ejection of the ink is stopped and the ejection of the ink is resumed from the state in which the nozzle is ejecting the ink of the liquid columnar state. As shown in Fig. 2A, in the state where the ink 112 is normally discharged, the liquid columnar ink 112 is discharged. When the discharge of the ink 112 is stopped, the ink 112 is attached to the tip of the nozzle 111 as shown in Fig. 2B. The ink 112 attached to the tip of the nozzle 111 dries with time. As a result, the density and viscosity of the ink 112 become high. In particular, when the time from the discharge stop of the ink 112 to the resumption becomes long, the increase in the concentration and viscosity of the ink 112 becomes remarkable. As a result, even if the ejection of the ink 112 is resumed, the liquid columnar ink may not be ejected from the nozzle 111 as shown in Fig. 2C. As shown in Fig. 2C, when the liquid columnar ink is not ejected, there is a problem that ink cannot be applied as intended.

In order to solve such a problem, in the nozzle printing apparatus of patent document 1, the nozzle is stored in the state in which the tip part of the nozzle contacted the storage liquid heated while ink application | coating was not performed. In this way, the tip of the nozzle is in contact with the storage liquid, whereby an increase in the concentration and viscosity of the ink during storage is prevented.

Japanese Patent Publication No. 2010-69374

As described above, in the method in which the nozzle is in contact with the storage liquid, since the storage liquid is mixed with the ink in the nozzle, the ink in the nozzle may be contaminated. In particular, in the conventional technique, since the ink is heated, deterioration of the ink may be promoted by heating of the ink. In this case, the ink in the nozzle may be further contaminated.

It is therefore an object of the present invention to provide a nozzle printing apparatus capable of preventing contamination of ink and removing ink adhering to the tip of the nozzle, and a maintenance method thereof.

The nozzle printing apparatus which concerns on one side of this invention is a nozzle which discharges the liquid columnar ink of a predetermined | prescribed flow volume,

A removal device for removing ink adhering to the tip of the nozzle by bringing an absorbing member that absorbs ink close to the tip of the nozzle.

Respectively.

When the ink attached to the tip of the nozzle is removed, the removal device may have a predetermined gap between the tip of the nozzle and the absorbent member to bring the absorbent member closer to the tip of the nozzle.

When the ink attached to the tip of the nozzle is removed, the removing means may bring the absorbing member closer to the tip of the nozzle in a state where ink is discharged from the nozzle.

The first flow rate of the ink discharged from the nozzle when the removal device removes the ink attached to the tip of the nozzle is supplied to the object from the nozzle after the removal device removes the ink attached to the tip of the nozzle. It may be larger than the second flow rate of the ink.

The maintenance method of the nozzle printing apparatus which concerns on one aspect of this invention is a maintenance method of the nozzle printing apparatus provided with the nozzle which discharges the liquid columnar ink of a predetermined | prescribed flow volume,

And removing the ink adhering to the tip of the nozzle by bringing the absorbing member that absorbs the ink into the tip of the nozzle.

According to the present invention, a nozzle printing apparatus and its maintenance method capable of preventing contamination of ink and removing ink adhering to the tip of the nozzle can be realized.

1 is a diagram schematically showing the state of the nozzle 11 and the ink 12 discharged from the nozzle 11.
2 is a diagram schematically showing the states of the nozzle and the ink.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail, referring an accompanying drawing. In the description of the drawings, the same reference numerals are used for the same or equivalent elements, and redundant descriptions are omitted.

Hereinafter, with reference to FIG. 1, the nozzle printing apparatus 10 of this embodiment and its operation | movement are demonstrated. FIG. 1 is a diagram schematically showing a state of the nozzle 11 and the ink 12 discharged from the nozzle 11.

As shown in FIG. 1A, in a state where the ink 12 is normally discharged from the nozzle 11, the liquid columnar ink 12 is discharged from the nozzle 11. The ink 12 is applied to a predetermined position of the object 20 by relatively moving the nozzle 11 and the object 20 disposed below the nozzle while maintaining this state. The nozzle printing apparatus 10 may be provided with the flow regulator 22 which adjusts the flow volume of the ink 12 discharged from the nozzle 11. The nozzle printing apparatus 10 may be provided with a controller 24 for controlling the flow regulator 22.

For example, when the application of ink to the object 20 is completed, the object 20 on which the application of ink is completed is replaced with a new object 20. During this replacement, the ejection of the ink 12 from the nozzle 11 is stopped. When the ejection of the ink 12 is stopped, the ink 12 is attached to the tip of the nozzle 11 as shown in Fig. 1B.

The ink 12 attached to the tip of the nozzle 11 dries with time. As a result, the density and viscosity of the ink 12 become high.

When the replacement of the object 20 is completed, the ejection of the ink 12 from the nozzle 11 is resumed. In this embodiment, the removal apparatus 14 (removing means) removes the ink 12 adhering to the front end of the nozzle 11 before the ejection of the ink 12 is resumed. As shown in FIG. 1C, the removal device 14 moves the absorbing member 13 that absorbs the ink 12 close to the tip of the nozzle 11, thereby adhering to the tip of the nozzle 11. Remove (12).

The absorbing member 13 may be a member that absorbs at least the ink 12, and is realized by, for example, a nonwoven fabric, a nonwoven paper, a porous material, a super absorbent polymer, or the like. Among these, nonwoven fabric and nonwoven paper are preferable.

The removal apparatus 14 is provided with the holding means which hold | maintains the absorbing member 13 so that it is movable, for example. This holding means is realized by, for example, a manipulator, a robot hand, or the like. The absorbing member 13 may be disposed just below the retracted position of the nozzle 11. In this case, the absorbing member 13 may rise toward the nozzle 11 as needed. Conversely, the nozzle 11 may descend toward the absorbing member 13. When the absorbing member 13 is provided in the sheet or the like, the holding means holds the sheet provided with the absorbing member 13. By moving this sheet, the absorbing member 13 is moved.

The removal device 14 can also make the absorbing member 13 contact the tip of the nozzle 11. When the ink 12 adhering to the front end of the nozzle 11 is removed, the removal device 14 has a predetermined gap between the front end of the nozzle 11 and the absorbent member 13 and the absorbent member 13 is removed. It is preferable to approach the tip of the nozzle 11. The quantum spacing when the front end of the absorbent member 13 and the nozzle 11 are closest is at least equal to the interval between the absorbent member 13 and the ink 12. The interval is, for example, 2000 µm or less, preferably 1000 µm or less. The lower limit of the quantum spacing when the front ends of the absorbing member 13 and the nozzle 11 are closest to each other is not particularly set. As for the space | interval, 200 micrometers or more are preferable from a positional precision or operability viewpoint.

Even if the absorbent member 13 is constituted by a flexible member, if the tip of the nozzle 11 and the contact of the absorbent member 13 are repeated a plurality of times, the tip of the nozzle 11 may be damaged. However, by providing a predetermined gap between the tip of the nozzle 11 and the absorbent member 13 when the ink is removed, it is possible to prevent the nozzle from being damaged when the ink is removed.

When the ink 12 attached to the tip of the nozzle 11 is removed, the removal device 14 moves the absorbing member 13 to the nozzle 11 in a state where the ink 12 is discharged from the nozzle 11. It is preferable to approach to the tip of.

The timing at which the ink 12 is discharged from the stopped state of the ink 12 is not particularly limited. For example, (1) in a state in which discharge of ink is stopped, the absorbing member 13 is brought close to the tip of the nozzle 11, and the ink 12 and the absorbing member 13 attached to the tip of the nozzle 11 are attached. After the contact with each other, the ink 12 may be discharged from the nozzle 11. (2) The ink 12 and the absorbing member 13 after the ink 12 adhered to the tip of the nozzle 11 and the ink 12 are discharged before contacting the absorbing member 13 in advance. This may be in contact.

When a predetermined time elapses after the discharge of the ink 12 is stopped, the concentration and viscosity of the ink 12 attached to the tip of the nozzle 11 increase. For this reason, even if the absorbing member 13 is in contact with such ink 12, there is a possibility that the ink 12 attached to the tip of the nozzle 11 cannot be removed smoothly. On the other hand, when the ink 12 is discharged from the nozzle 11, the new ink 12 mixes with the ink attached to the tip of the nozzle 11. As a result, the density and viscosity of the ink adhered to the tip of the nozzle 11 decrease. In the above embodiment, by removing the ink in such a state, the ink can be smoothly removed.

When the removal device 14 removes the ink 12 attached to the tip of the nozzle 11, the first flow rate of the ink 12 discharged from the nozzle 11 is that the removal device 14 is connected to the nozzle 11. It is preferable that the second flow rate of the ink supplied from the nozzle 11 to the object 20 after removing the ink 12 adhering to the tip of the nozzle 12 is greater. Here, the flow rate of the ink supplied to the object 20 after removing the ink 12 means the flow rate of the ink when the ink is actually applied to an object such as a substrate. The flow rate of the ink 12 can be adjusted by the flow regulator 22.

The removal device 14 removes the ink 12 attached to the tip of the nozzle 11 while the nozzle 11 discharges the ink 12 having a flow rate larger than that of the ink 12 actually applied. In this case, by applying a high pressure to the ink 12, the movement of the ink 12 attached to the tip of the nozzle 11 to the absorbing member 13 is promoted. In addition, since the concentration and viscosity of the ink 12 attached to the tip of the nozzle 11 decrease as described above, the removal of the ink 12 can be performed more smoothly.

When the flow rate of the ink 12 when the ink 12 is actually applied to the substrate or the like is a numerical value "1", the nozzle when the removal device 14 removes the ink 12 attached to the tip of the nozzle 11 The flow rate of the ink 12 discharged from the (11) is, for example, a numerical value of 1 to 3, and preferably a numerical value of 1.2 to 2.

The time during which the absorbent member 13 is in contact with the ink 12 may be a time for removing the ink 12 attached to the tip of the nozzle 11, for example, 0.5 seconds to 20 seconds, preferably Preferably from 1 second to 5 seconds.

After the removal of the ink 12 is finished, for example, after the position of the substrate is aligned, the ejection of the ink 12 is resumed. It is preferable that the time from the removal of the ink 12 to the end until the discharge of the ink 12 is resumed is short, for example, 10 seconds or less, preferably 1 second or less.

When the ink 12 is removed in the state in which the ink 12 is discharged from the nozzle 11, the ink 12 may be continuously discharged as it is even after the removal of the ink 12 is completed.

After the ink 12 adhering to the tip of the nozzle 11 is removed, the ink 12 is ejected from the nozzle 11, so that the ink 12 of the liquid columnar is intended as shown in Fig. 1 (d). ) May be discharged. Thereby, application | coating can be performed as intended.

By relatively moving the object 20 and the nozzle 11 while ejecting the ink 12 from the nozzle 11, the ink 12 can be applied onto the object 20 in a predetermined pattern. The object 20 is fixed to the surface plate, for example. By moving this surface plate at a predetermined speed, the object 20 can move relative to the nozzle 11.

For example, a plurality of organic EL elements can be formed using the nozzle printing apparatus 10 by pattern-coating an ink containing a material that becomes a layer constituting an organic EL element on a drive substrate for an organic EL display device.

The inner diameter of the nozzle 11 is determined by the ink 12 used and the kind of thin film to be formed. The internal diameter of the nozzle 11 which discharges the ink 12 for forming the predetermined layer of organic electroluminescent element is 5 micrometers-50 micrometers, for example, Preferably they are 9 micrometers-15 micrometers.

The discharge amount (flow rate) of the ink 12 discharged from the nozzle 11 is determined by the film thickness of the thin film to be formed, the concentration of the ink 12 and the relative speed between the nozzle 11 and the object 20 and the like. When the nozzle 11 discharges the ink 12 for forming a predetermined layer of the organic EL element, the discharge amount of the ink 12 is, for example, 10 µL / min to 200 µL / min, preferably 30 μL / min to 100 μL / min.

The optimum value of the viscosity of the ink 12 is set by the precision of the patterning of the thin film formed, the internal diameter of the nozzle 11, etc. When the nozzle 11 discharges the ink 12 for forming a predetermined layer of the organic EL element, the viscosity of the ink 12 is, for example, from 1 cP (0.001 Pa.s) to 50 cP (0.05 Pa). S), preferably 3 cP (0.003 Pa.s) to 20 cP (0.02 Pa.s).

The concentration of the ink 12 is determined by the film thickness of the thin film to be formed, the discharge amount of the ink 12, the relative speed of the nozzle 11 and the object 20, and the like. When the nozzle 11 discharges the ink 12 for forming a predetermined layer of the organic EL element, the concentration of the ink 12 is, for example, 1 mg / mL to 50 mg / mL, preferably 5 mg / mL to 20 mg / mL.

The material of the ink 12 discharged from the nozzle 11 is suitably selected according to the kind of thin film formed. The ink 12 for forming the predetermined layer of organic electroluminescent element consists of the liquid which melt | dissolved the material used as a predetermined layer in the predetermined solvent.

As a predetermined layer which comprises an organic EL element, an anode, a hole injection layer, a hole transport layer, an electron block layer, a light emitting layer, a hole block layer, an electron transport layer, an electron injection layer, a cathode, etc. are mentioned, for example. Hereinafter, the material of each layer is illustrated. Among them, each layer can be formed by appropriately selecting a material that can be used for the nozzle printing method to produce the ink, and pattern-coating the ink by the nozzle printing apparatus 10 described above. Even when the organic EL element is composed of a plurality of predetermined layers, it is not necessary to form all the layers using the nozzle printing apparatus 10.

<Hole injection material>

Examples of the hole injection material constituting the hole injection layer include oxides such as vanadium oxide, molybdenum oxide, ruthenium oxide and aluminum oxide, phenylamine, starburst amine, phthalocyanine, amorphous carbon, polyaniline and polythiophene derivatives. Can be mentioned.

<Hole transporting layer material>

Examples of the hole transport material constituting the hole transport layer include polyvinylcarbazole or derivatives thereof, polysilane or derivatives thereof, polysiloxane derivatives having an aromatic amine in the side chain or the main chain, pyrazoline derivatives, arylamine derivatives, stilbene derivatives, and triphenyl. Diamine derivatives, polyaniline or derivatives thereof, polythiophene or derivatives thereof, polyarylamines or derivatives thereof, polypyrrole or derivatives thereof, poly (p-phenylenevinylene) or derivatives thereof, or poly (2,5-thienylenevinyl) Lene) or derivatives thereof, and the like.

<Luminescent material>

The light emitting layer is usually formed of an organic material that mainly emits fluorescence and / or phosphorescence, or a dopant supporting the organic material. The dopant is added, for example, to improve the luminous efficiency or to change the emission wavelength. The organic material contained in the light emitting layer may be a low molecular weight compound or a high molecular compound. Organic material preferably comprises a compound of a number average molecular weight in terms of polystyrene of 10 ³ to 10 ⁸ as the polymer compound. As a light emitting material which comprises a light emitting layer, the following pigment | dye type material, a metal complex system material, a polymer type material, and a dopant material are mentioned, for example.

(Color based material)

Examples of the dye-based material include a cyclopentamine derivative, a tetraphenylbutadiene derivative compound, a triphenylamine derivative, an oxadiazole derivative, a pyrazoloquinoline derivative, a distyrylbenzene derivative, a distyryl arylene derivative, a pyrrole derivative and a thi Ophen ring compounds, pyridine ring compounds, perinone derivatives, perylene derivatives, oligothiophene derivatives, oxadiazole dimers, pyrazoline dimers, quinacridone derivatives, coumarin derivatives and the like.

(Metal complex system material)

Examples of the metal complex system material include rare earth metals such as Tb, Eu, and Dy, or Al, Zn, Be, Ir, and Pt in the central metal, and include oxadiazole, thiadiazole, phenylpyridine, and phenylbenz. The metal complex which has imidazole, quinoline structure, etc. in a ligand can be mentioned, For example, the metal complex which has light emission from triplet excited states, such as an iridium complex and a platinum complex, an aluminum quinolinol complex, a benzoquinolinol beryllium The complex, a benzoxazolyl zinc complex, a benzothiazole zinc complex, an azomethyl zinc complex, a porphyrin zinc complex, a phenanthroline europium complex, etc. are mentioned.

(Polymeric material)

As the polymer material, polyparaphenylene vinylene derivatives, polythiophene derivatives, polyparaphenylene derivatives, polysilane derivatives, polyacetylene derivatives, polyfluorene derivatives, polyvinylcarbazole derivatives, the pigment-based materials or metal complexes And a polymerized systemic light emitting material.

(Dopant material)

As the dopant material, for example, perylene derivatives, coumarin derivatives, rubrene derivatives, quinacridone derivatives, squarylium derivatives, porphyrin derivatives, styryl pigments, tetracene derivatives, pyrazolone derivatives, decacyclenes, phenoxa John etc. can be mentioned. The thickness of such a light emitting layer is usually about 2 nm-200 nm.

<Electron transport layer material>

As the electron transporting material constituting the electron transporting layer, known materials can be used, and oxadiazole derivatives, anthraquinomethane or derivatives thereof, benzoquinone or derivatives thereof, naphthoquinone or derivatives thereof, anthraquinone or derivatives thereof, tetra Cyanoanthracinodimethane or derivatives thereof, fluorenone derivatives, diphenyldicyanoethylene or derivatives thereof, diphenoquinone derivatives, or metal complexes of 8-hydroxyquinoline or derivatives thereof, polyquinoline or derivatives thereof, polyquinoxaline Or derivatives thereof, polyfluorene or derivatives thereof, and the like.

Among these, as the electron transporting material, an oxadiazole derivative, a benzoquinone or a derivative thereof, an anthraquinone or a derivative thereof, a metal complex of 8-hydroxyquinoline or a derivative thereof, a polyquinoline or a derivative thereof, a polyquinoxaline or a derivative thereof , Polyfluorene or a derivative thereof is preferable, and 2- (4-biphenylyl) -5- (4-t-butylphenyl) -1,3,4-oxadiazole, benzoquinone, anthraquinone and tris ( 8-quinolinol) aluminum and polyquinoline are more preferred.

<Electron injection layer>

As the material constituting the electron injection layer, an optimal material is appropriately selected according to the type of the light emitting layer, and an alloy, alkali metal or alkaline earth metal containing at least one of alkali metal, alkaline earth metal, alkali metal and alkaline earth metal may be used. Oxides, halides, carbonates, or mixtures of these substances; and the like. Examples of alkali metals, oxides, halides, and carbonates of alkali metals include lithium, sodium, potassium, rubidium, cesium, lithium oxide, lithium fluoride, sodium oxide, sodium fluoride, potassium oxide, potassium fluoride, rubidium oxide, rubidium fluoride, and oxides. Cesium, cesium fluoride, lithium carbonate and the like. Examples of the alkaline earth metals, oxides, halides, and carbonates of alkaline earth metals include magnesium, calcium, barium, strontium, magnesium oxide, magnesium fluoride, calcium oxide, calcium fluoride, barium oxide, barium fluoride, strontium oxide, strontium fluoride, magnesium carbonate, and the like. Can be mentioned.

The solvent of the ink is not particularly limited as long as it dissolves the solute. Examples of the solvent include chlorine solvents such as chloroform, methylene chloride and dichloroethane, ether solvents such as tetrahydrofuran, aromatic hydrocarbon solvents such as toluene and xylene, and acetone. And ketone solvents such as methyl ethyl ketone, ester solvents such as ethyl acetate, butyl acetate, and ethyl cellosolve acetate, and water.

As mentioned above, although preferred embodiment of this invention was described in detail, this invention is not limited to the said embodiment.

11: nozzle
12: ink
13: absorbent member

Claims (5)

A nozzle for discharging ink on a liquid column of a predetermined flow rate,
A removal device for removing ink adhering to the tip of the nozzle by bringing an absorbing member that absorbs ink close to the tip of the nozzle.
Nozzle printing apparatus having a. The said removal apparatus is provided with the clearance gap between the front-end | tip of the said nozzle and the said absorbing member, when the ink adhering to the front-end | tip of the said nozzle is removed, The said absorbing member is close to the front-end | tip of the said nozzle. Nozzle printing device. 3. The nozzle printing according to claim 1 or 2, wherein the removal device is configured to bring the absorbing member closer to the tip of the nozzle in a state where ink is ejected from the nozzle when the ink attached to the tip of the nozzle is removed. Device. The first flow rate of the ink discharged from the nozzle when the removal device removes the ink attached to the tip of the nozzle is characterized in that the removal device is at the tip of the nozzle. A nozzle printing apparatus, wherein more than the second flow rate of ink supplied to the object from the nozzle after removing the ink adhering to the nozzle. As a maintenance method of the nozzle printing apparatus provided with the nozzle which discharges the ink of the liquid columnar of a predetermined | prescribed flow volume,
And removing the ink adhering to the tip of the nozzle by bringing an absorbing member that absorbs ink into the tip of the nozzle.

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