JP2013230469A - Ink-jet film-forming method and apparatus therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink-jet film-forming method and an apparatus therefor.SOLUTION: There is provided an ink-jet film-forming method of forming a film through a plurality of injection processes, the ink-jet film-forming method being characterized in that when a droplet is injected in second and succeeding injecting operations to a position contacting or overlapping a droplet having been impacted in precedent injecting operations, the injection is performed after the droplet on a work becomes dry enough not to flow.

Description

The present invention relates to an inkjet film forming method and an apparatus for an inkjet coating apparatus provided with an inkjet recording head (hereinafter referred to as “inkjet head”), and in particular, dirt, debris, and dust attached to the nozzle surface of the inkjet head and its periphery. The present invention relates to an ink-jet film forming method and an apparatus therefor.
In addition, the inkjet head in this specification shall mean an inkjet head provided with a single or several nozzle unless there is particular notice.

In an ink jet recording apparatus, in order to maintain high quality recording quality, it is necessary to remove ink, dust, and the like remaining on the ink ejection surface of the ink jet recording head.
In Patent Document 1, in the method of cleaning by performing the wiping operation with the wiping blade facing the ink ejection surface of the head, there are contrivances about the material, angle, and contact method of the wiping blade in order to improve the cleaning performance. It is disclosed.

  In Patent Document 2, an ink absorbing slit is provided on the downstream side in the recovery operation direction of the blade cleaning with respect to the ejection port, and the ink scraped by the blade is provided in a slit shape in parallel with the plurality of ejection ports. A method for improving the performance by sucking the ink through an ink absorbing slit having a suction port is disclosed.

  In Patent Document 3, after spraying the nozzle surface of the inkjet head and the periphery thereof from the spray nozzle to clean the nozzle surface, the cleaning liquid adhering to the nozzle of the inkjet head and the periphery thereof is wiped with a blade. It is disclosed.

  Patent Document 4 discloses a method in which an inkjet head having a plurality of nozzles arranged at a predetermined pitch is moved relative to a substrate and droplets of an alignment film are ejected from the nozzles onto the substrate. A droplet discharge of an alignment film, wherein a direction of movement relative to the substrate of the inkjet head is inclined by a predetermined angle with respect to an arrangement direction of picture elements configured in a lattice pattern on the substrate A method is disclosed.

  In Patent Document 5, a head support structure including a single or a plurality of inkjet heads each having a plurality of nozzles arranged at a constant interval, and a plurality of nozzles in a direction orthogonal to the arrangement direction of the plurality of nozzles. A substrate transfer mechanism having a substrate transfer table that can move relative to the nozzle, and sprays a thin film forming solution from the plurality of nozzles onto the surface of the substrate mounted on the substrate transfer table. In a non-contact type thin film forming apparatus for forming a thin film by coating, a vacuum chamber as a spray coating film forming chamber including at least the substrate transport table, the ink jet head, and the head support structure, and a reduced pressure atmosphere And a decompression means for decompressing the inside of the vacuum chamber in order to perform spray coating.

  Patent Document 6 discloses an inspection process in which an alignment film material is landed by droplets using an inkjet nozzle, and an abnormality of the inkjet nozzle is inspected from the landed droplet pattern, and a droplet pattern is predetermined in this inspection process. Forming an alignment film comprising: an inkjet film and a substrate facing each other when in the range; and an alignment film material deposited on the substrate by droplets of an alignment film material using the inkjet nozzle A method is disclosed.

  In Patent Document 7, in a device manufacturing method including a step of discharging a liquid material from a droplet discharge head to a pattern formation region of a substrate, the liquid material is discharged to a predetermined region other than the pattern formation region. Disclosed is a device manufacturing method comprising a flushing step.

JP 2004-291364 A JP 2004-42571 A JP 2002-19132 A JP 2006-320839 A JP 2006-289355 A JP 2006-087772 A JP 2003-282245 A

  An object of this invention is to provide the inkjet film-forming method and apparatus which can solve the technical subject mentioned later.

A first invention is an ink-jet film forming method for forming a film by a plurality of ejection steps, and after the second ejection operation, the droplet is brought into contact with or overlapping with a droplet landed by the preceding ejection operation. In the inkjet film forming method, the injection is performed after waiting for a dry state where the droplets on the workpiece do not flow.
According to a second aspect, in the first aspect, in the first ejection operation, the droplets of the ejected droplet group are arranged apart from each other.
The third invention is characterized in that, in the first or second invention, the drying time of the droplets on the work is shortened by raising the temperature of the table on which the work is placed.
A fourth invention is characterized in that in any one of the first to third inventions, film formation is performed by an ink jet head having a plurality of ejection ports.
A fifth invention is characterized in that, in any one of the first to fourth inventions, the number of injection steps is increased and the injection amount per time is reduced.
According to a sixth invention, in any one of the first to fifth inventions, a wiring pattern is formed by a film.
According to a seventh invention, in any one of the first to sixth inventions, a droplet is ejected to a position where the droplet contacts or overlaps after waiting for 20 to 100 seconds from the landing of the droplet by the preceding ejection operation. It is characterized by performing.
An eighth invention is characterized in that, in any one of the first to seventh inventions, the film thickness of the formed film is several nm to several tens of μm.
According to a ninth aspect of the present invention, there is provided an inkjet coating apparatus that performs coating while relatively moving an inkjet head and a work table positioned below the inkjet head, wherein the control device is the inkjet film forming method according to any one of the first to eighth aspects of the invention. Is an ink jet coating apparatus.

  According to the present invention, the thickness difference of the entire surface can be reduced in the film formation by inkjet as compared with the conventional method.

1 is an overall schematic plan view of an apparatus including a cleaning mechanism according to Embodiment 1. FIG. 1 is an overall schematic side view of an apparatus including a cleaning mechanism according to Embodiment 1. FIG. FIG. 3 is a schematic explanatory diagram showing one form of a cleaning mechanism of Example 1. It is a schematic block diagram which shows the other form of the cleaning mechanism of Example 1. FIG. FIG. 3 is a plan view illustrating a configuration of a cleaning unit according to the first embodiment. 1 is a side cross-sectional view illustrating a schematic configuration of a cleaning unit according to Embodiment 1. FIG. It is explanatory drawing of the washing | cleaning process and drying process by the washing | cleaning unit which concerns on Example 1. FIG. 2 is a flowchart of an inkjet head cleaning process and a drying process according to Example 1. FIG. It is explanatory drawing of the nozzle test | inspection mechanism which concerns on Example 1. FIG. It is the flowchart which showed the execution procedure of application | coating control of an inkjet head. It is the conceptual block diagram simplified in order to demonstrate the action | operation of an inkjet head. It is explanatory drawing of the pre-processing operation | movement of the inkjet head in the structure of FIG. It is explanatory drawing of the post-processing operation | movement of the inkjet head in the structure of FIG. It is comparison explanatory drawing of the conventional thick film formation method and the thick film formation method of this invention. It is a wiring pattern which can be formed by the film forming method of the present invention. 6 is a configuration diagram of a maintenance mechanism according to Embodiment 2. FIG. It is the side view which transparently showed the sucking and flushing unit concerning Example 2. 10 is a signal waveform output from the devices according to the second embodiment.

The legend of the main symbols used in the drawings is shown below.
2 Liquid material / 3 Cleaning liquid / 4 Used cleaning liquid (waste liquid) / 5 Negative pressure / 6 Nozzle / 7 Opening / closing mechanism / 8 Signal generator / 9 Communication member / 10 Inkjet head / 11 Liquid material discharge surface / 12a, 12b Liquid material Bottle / 13 Cleaning liquid bottle / 14 Work table / 15 Personal computer (PC) / 16 Operation desk / 19 Pressure supply pump / 20 Cleaning unit / 21 Liquid receiving part / 22 Discharge valve / 23 Cleaner lip / 24 Bottom suction port / 25 Cleaning liquid Supply port / 26 Cleaning liquid recovery port / 28 Opening / 31a, 31b Cleaning liquid nozzle solenoid valve / 32a, 32b Side nozzle atmospheric release valve / 33 Supply valve / 34a, 34b Negative pressure solenoid valve / 35 Cleaning liquid supply valve / 36 Material switching valve / 37 Ejector / 38 Regulator / 40 Waste liquid tank / 41 Manual cock / 51 Open / close solenoid valve / 52 Quantity sensor / 61 Contact member / 62 Frame / 63 Support member / 64 Attachment member / 66 Joint / 71 Actual liquid / 72 Film for inspection / 73 Plate / 74 Imaging device / 75 Reflected illumination / 76 Transmitted illumination / 77 Field of view / 78 Landed actual liquid / 81 Feeding roller / 82 Rolling roller / 101 Inkjet head control box / 102 Sucking / flushing unit / 103 Capping unit / 104 Image camera / 105 Liquid material switching unit / 106 Inkjet control board / 107 Liquid material tank / 108 Emergency stop switch / 109 Base plate / 110 Beam / 112 Various pneumatic equipment / 113 Utility box / 114 Control box / 121 X-axis moving mechanism / 122 Y-axis moving mechanism / 123 Z-axis moving mechanism / 124 θ Shaft rotation mechanism 125 H.theta axis rotating mechanism / 151 first valve / 152 second valve

The present invention is based on the following four technical ideas related to an ink jet coating apparatus.
(1) Cleaning method and mechanism [i] Problem The first technical idea is to improve that the ability to remove droplets adhering to the ejection surface of an inkjet head is low.
Further, since the conventional cleaning mechanism is large in size, it is a problem to be solved to aim for further miniaturization.
Moreover, it is a problem to be solved to perform cleaning without using a hard blade as in the prior art. This is because when the blade is brought into contact with the nozzle of the ink jet head and its peripheral portion, there is a problem that abrasion dust is generated. When wear dust is generated, nozzles are clogged, and there is a problem that the surrounding environment is contaminated. Further, if there is a possibility of generation of wear dust, use in a clean room is restricted.

[Ii] Summary In order to remove the liquid material adhering to the ejection surface of the inkjet head, it is effective to bring the adhering liquid material into contact with a cleaning liquid (cleaning agent) that dissolves the liquid material and dissolve the liquid material with the cleaning liquid. It is.
Moreover, although the injection port which inject | emits a liquid material is formed in the said injection surface, it is important to make the periphery contact with a washing | cleaning liquid uniformly. This is particularly important in an ink jet head having a plurality of exit ports on the exit surface.
The first technical idea is that the cleaning liquid supplied from one end of the ejection surface of the ink jet head flows on the surface of the ejection surface and is collected from one end farthest from the end to which the cleaning liquid is supplied. By using the cleaning liquid to flow from the end of the injection surface to the opposite end of the injection surface while dissolving the liquid material adhering to the injection surface, the injection surface can be uniformly and efficiently cleaned.
Preferably, the cleaning liquid is supplied to the injection surface from a plurality of positions at one end of the injection surface, and the cleaning liquid is collected from the plurality of positions at the opposite end. Here, the number of positions for supplying the cleaning liquid need not be the same as the number of positions for recovering the cleaning liquid.
More preferably, the cleaning liquid is supplied from one end on the longitudinal side of the ejection surface of the inkjet head, and the cleaning liquid is recovered from the opposite end on the longitudinal direction side of the ejection surface. This is because the distance that the cleaning liquid flows on the inkjet ejection surface is shortened, and the cleaning efficiency can be improved.
It is also effective for a unit that increases in size, such as an inkjet head having a plurality of ejection openings.
Further, the cleaned injection surface is wet with the cleaning liquid, but is preferably dried in order to shorten the waiting time. As a means for drying the cleaned injection surface, natural drying or air blow drying is preferable because contamination of the injection surface can be prevented.
As described above, when the droplets are not attached to the ejection surface of the inkjet head, the accuracy of the amount of droplets ejected from the inkjet head and the accuracy of the landing position of the droplets on the workpiece are improved.

The cleaning liquid of a preferred embodiment is composed of a colorless solvent having a factor that dissolves the ink (for example, a main component solvent that dissolves the ink).
By the way, the ink generally used for an ink jet printer can be classified into a dye system or a pigment system. A dye is a colorant that is dispersed or solvated as a molecule in a carrier medium. The carrier medium is liquid or solid at room temperature. A commonly used carrier medium is water or a mixture of water and an organic cosolvent. In general, water is the main component, and it contains a colorant and a wetting agent such as glycerin for the purpose of preventing clogging. When water is used as the carrier medium, such inks also generally have the disadvantage of poor water fastness.
A pigment is a colorant that is insoluble in the carrier medium, but is dispersed or suspended in the form of small particles and is often stabilized by the use of a dispersant so that it does not agglomerate and precipitate. Many such compounds are known. For example, a pigment ink used as a colorant by finely pulverizing a pigment such as an organic pigment or carbon black using a surfactant or a dispersant and dispersing it in a medium such as water. and so on.
This technical idea can be applied regardless of dye-based or pigment-based. The mainstream ink viscosity is as low as several tens of cps, but it can be applied to medium viscosity of several hundred cps or higher as long as it can be ejected by flight.
This technical idea can also be applied to functional inks used for wiring pattern printing on printed circuit boards, application of lubricants to minute parts, outdoor light-resistant display material printing, UV curable ink printing, and the like.

[Iii] Implementation Procedure Cleaning of the inkjet head is performed in the order of steps A to D (see FIG. 6). “B. Cleaning operation” describes an example of a procedure in the configuration shown in FIG.
<< A. Setting the inkjet head to the cleaning mechanism >>
The inkjet head 10 and the cleaning unit 20 of the cleaning mechanism are brought into contact with each other. That is, the lower surface of the inkjet head 10 is brought into contact with the upper surface of the cleaning unit 20 so as to cover the liquid receiving portion 21 provided in a concave shape at the center of the cleaning unit 20. The cleaner lip 23 serves as a contact surface between the lower surface of the inkjet head 10 and the upper surface of the cleaning unit 20.

<< B. Cleaning work >>
1) The cleaning liquid nozzle electromagnetic valves 31a and 31b are opened, and the flow paths connected through the electromagnetic valves 31a and 31b are communicated.
2) The side nozzle atmosphere release valves 32a and 32b block communication with the atmosphere, and set the flow path connected via the release valves 32a and 32b to the communication position. (The cleaning unit 20 and the electromagnetic valve 31a are communicated by the release valve 32a, and the electromagnetic valve 31b and the discharge valve 22 are communicated by the release valve 32b.)
3) The discharge valve 22 allows the ejector 37 and the liquid receiving part 21 of the cleaning unit 20 to communicate with each other, and the negative pressure solenoid valves 34a and 34b are opened.
4) Through the steps up to 3), the negative pressure by the ejector 37 acts on the flow path of the cleaning unit 20, and the cleaning liquid stored in the cleaning liquid bottle 13 is supplied to the cleaning unit 20.
5) The cleaning liquid supplied to the cleaning unit 20 is supplied from the cleaning liquid supply port 25 to the inkjet head 10. The cleaning liquid supply port 25 is formed close to the outer periphery of the lower surface of the inkjet 10, and the cleaning liquid discharged from the cleaning liquid supply port 25 is efficiently supplied to the vicinity of the outer peripheral end of the lower surface of the inkjet head 10.
6) The cleaning liquid supplied to the lower surface of the ink jet head 10 flows on the lower surface of the ink jet head 10 and is recovered again by the cleaning unit 20 from the cleaning liquid recovery port 26 formed near the cleaning liquid supply side on the lower surface of the ink jet 10. Alternatively, the ink is separated from the lower surface of the inkjet head 10 before reaching the cleaning liquid recovery port 26, and is recovered in the liquid receiving portion 21 of the cleaning unit 20. The liquid receiving part 21 communicates with the discharge valve 22, but the discharge valve 22 is located at a position where communication between the other flow path via the discharge valve 22 and the liquid receiving part 21 is blocked. The cleaning liquid accumulates in
The cleaning liquid flowing into the cleaning unit 20 from the cleaning liquid recovery port 26 is recovered in the waste liquid tank 40 through the discharge valve 22 and the ejector 37.
7) After the cleaning is sufficiently performed, the cleaning liquid nozzles 31a and 31b are closed, the negative pressure solenoid valves 34a and 34b are closed, and the side nozzle atmosphere release valves 32a and 32b are positioned so as to communicate with the atmosphere. Thereby, the supply of the cleaning liquid to the cleaning unit 20 is stopped, and the pressure of the liquid receiving portion 21 is shifted from the negative pressure to the atmospheric pressure.

<< C. Desorption from inkjet head cleaning mechanism >>
The lower surface of the inkjet head 10 is separated from the upper surface of the cleaning unit 20, and a gap is formed between the lower surface of the inkjet head 10 and the upper surface of the cleaning unit 20. The gap is a distance at which an appropriate air flow is generated in order to perform a subsequent drying operation.

<< D. Drying work >>
1) The discharge valve 22 is switched so that the waste liquid tank 40 and the cleaning unit 20 communicate with each other, and the negative pressure solenoid valves 34a and 34b are opened.
2) As a result, the liquid receiving part 21 of the cleaning unit 20 and the waste liquid tank 40 communicate with each other, and a negative pressure acts on the liquid receiving part 21, so that the cleaning liquid stored in the liquid receiving part 21 enters the waste liquid tank 40. The cleaning liquid that has flowed into the waste liquid is collected in the waste liquid tank 40.
3) Further, a gap is provided between the lower surface of the inkjet head 10 and the upper surface of the cleaning unit 20, and air flows into the liquid receiving portion 21 from the gap so as to offset the negative pressure of the liquid receiving portion 21. The atmosphere flowing through this gap acts so that the cleaning liquid adhering to the lower surface of the inkjet head 10 drops, and the dropped cleaning liquid falls on the liquid receiving portion 21 and is collected in the waste liquid tank 40. The air flow (negative pressure) may be adjusted by adjusting the distance between the lower surface of the inkjet head 10 and the cleaning unit 20.
4) If this state is maintained even after the cleaning liquid stored in the liquid receiving portion 21 is collected in the waste liquid tank 40, the air flowing through the gap acts to dry the lower surface of the inkjet head 10. An ejection port through which the liquid material is ejected is formed on the lower surface of the inkjet head 10, but it can be dried without bringing other substances into contact with the lower surface, so that the ejection port is in an extremely clean state. Can be held.
5) After the lower surface of the ink jet head 10 is sufficiently dried, the negative pressure solenoid valves 34a and 34b are operated to the closed position to stop the negative pressure supply to the liquid receiving portion 21 of the cleaning unit 20.
6) Thereafter, the supply valve 33 is operated to connect the inkjet head 10 and the liquid material supply bottle 12, and the liquid material flow path is arranged so that the liquid material can be supplied to the inkjet head 10.

[Iv] Effect According to the first technical idea described above, since cleaning is performed with the cleaning liquid, wear dust is not generated.
Further, since the cleaning liquid is ejected by the action of negative pressure, the cleaning liquid is not supplied unless the inkjet head is in close contact with the cleaning unit. Therefore, even if the ink jet head and the cleaning unit are separated from each other, the supply of the cleaning liquid is stopped due to the vacuum break, and the cleaning liquid can be prevented from being ejected outside the cleaning unit.
Moreover, since the drying operation is also performed by the action of negative pressure, it is possible to prevent the outside of the cleaning unit from being contaminated with the cleaning liquid.

(2) Nozzle inspection method and mechanism [i] Problem Conventionally, since the inkjet coating apparatus is an inkjet system, it is necessary to place it at a necessary location due to nozzle failure, nozzle orientation, clogging of liquid material at the nozzle, etc. There was a problem that a necessary amount of droplets could not be properly applied.
In addition, in the inspection method in which a liquid material is dropped onto the inspection film as in Patent Document 6, the shape of the liquid droplet collapses before reaching the image recognition camera after landing, so that the shape of the liquid droplet is recognized. Even then, the inspection could not be performed with high accuracy.

[Ii] Summary The second technical idea is to perform nozzle inspection by dropping a liquid material onto an inspection member (adhered body) as in Patent Document 6. The difference from Patent Document 6 is not to focus on the applied liquid material (droplet), but to compare the portion of the adherend to which the liquid material is applied with the other portions.
In the best mode of the present invention, the adherend is composed of an inspection film made of a material exhibiting solubility. Thereby, even with a transparent liquid material with poor visibility, the spot where the liquid material has landed dissolves, and the inspection film becomes turbid (transparency changes or becomes opaque). Therefore, the visibility of the landed portion is high, and the landed portion can be easily detected. In particular, the effect when using a liquid material with high transparency is remarkable.
The adherend to which the liquid material lands is appropriately selected according to the liquid material to be ejected. The important thing is that the reflectance of the landing portion of the liquid material changes. When the landing spot of the adherend is dissolved, the reflectance changes due to irregular reflection or the like, so that the landing spot can be accurately extracted by image processing. It may be a combination of an adherend and a liquid material whose reflectivity changes by landing, and the liquid material may soak into the adherend. The aspect in which the liquid material soaks into the adherend is particularly effective in a liquid material that does not contain a solvent as a main component, for example, a liquid material that uses water as a solvent.
It is preferable that the adherend be dissolved (or soaked) quickly from the moment of landing of the liquid material. This is because if the liquid material that has landed on the upper surface of the adherend is held for a long time, the diameter of the landing mark becomes large. Preferably, an adherend made of a material that melts (or penetrates) so as to fall downward is used instead of a material that spreads during melting. For example, a polystyrene film is preferable for a liquid material using toluene as a solvent. The adherend preferably has a thickness that does not reach the back of the adherend due to the landing of the liquid material.
The adherend is preferably transparent, but is not necessarily transparent, and may be colored. What is important is that the distinction between the landing part and the non-landing part is good. The adherend includes not only those composed of a single material, but also those whose surface is coated, and those which are formed in layers with a plurality of films.
To identify the liquid material that has landed on the adherend, an imaging device such as a CCD camera or a sensing device such as a laser sensor can be used.
As the image processing, for example, edge extraction or binarization is performed on the image of the imaging field including the landing position, and the landing position is thereby extracted.

[Iii] Implementation Procedure The nozzle inspection process will be described with reference to an example of the procedure in the configuration shown in FIG.
1) The winding roller 82 is rotated, and a new inspection film 72 is positioned below the inkjet head 10. Here, the inspection film 72 positioned below the inkjet head 10 is positioned by the plate 73, and the distance from the inkjet head 10 is accurately maintained.
2) The actual liquid 71 is discharged from the inkjet head 10 and landed on the upper surface of the inspection film 72. Due to the landing, the inspection film 72 is dissolved, and a trace of landing is left.
3) Further, the winding roller 82 is rotated so that the landing position of the inspection film 72 is positioned above the imaging device 74.
4) The inspection film 72 is imaged by the imaging device 74. The imaging by the imaging device 74 may be performed with the inspection film 72 stopped or may be performed while the inspection film 72 is moved.
5) Based on the image data acquired by the imaging device 74, the state of the inkjet head 10 is inspected. Clogging can be inspected from the “missing” and “diameter” of the landing marks, and flying defects can be inspected from the deviation of the landing positions.

(3) Application control method [i] Problem It is an object to have a desired accuracy by preventing occurrence of problems such as clogging of nozzles of an ink jet head and realizing a stable ink discharge operation.
When the liquid material discharge operation is stopped, the flow path near the injection port of the ink jet head dries, causing clogging due to thickening of the liquid material and precipitation of solids from the liquid material, and flight bending of the discharged liquid material. There arises a problem that a stable discharge operation is not performed.
In addition, if the discharge stability of the liquid material deteriorates, there is a problem that a product that requires a desired accuracy cannot be manufactured, and in the mass production process, from the discharge work for one work to the discharge work for the next work, Processing such as loading / positioning of the next workpiece and alignment processing is required. During this time, the ink jet head must be kept on standby without performing an ejection operation, but there is a problem that the liquid material filled in the ink jet head is likely to be dried due to the standby.

[Ii] Summary The third technical idea is that after a discharge operation, the discharge liquid material filled in the flow path in the ink jet head is replaced with a liquid material (substitution material) having low volatility, and the discharge operation is started. It is characterized in that the replacement material is replaced again with the discharge liquid material immediately before. Here, the replacement material is preferably a liquid having a dissolving action on the liquid material or a liquid having a cleaning action.
Preferably, after the replacement material is filled in the flow path in the ink jet head, a cleaning step for cleaning the lower surface of the ink jet head in which the injection port for injecting the liquid material is formed is added.
There is no liquid material remaining in the inkjet head that has undergone the filling and cleaning steps of the above-mentioned replacement material, and there is no concern about thickening of the liquid material or precipitation of solids from the liquid material even during standby for discharge work. . Therefore, the occurrence of the above-described problem can be fundamentally eliminated.
According to this technical idea, the solid component does not precipitate or solidify, and the nozzle is not clogged even if the discharge operation standby time is long due to an unexpected trouble or the like. Furthermore, since the liquid material is filled in the ink jet head immediately before the discharge operation, a fresh liquid material can be applied to the workpiece.

[Iii] Execution procedure The coating operation is performed in the following order. First, the capping unit mounted on the lower surface of the inkjet head is detached. The capping unit is applied to keep the ejection port formed on the lower surface of the inkjet head clean and prevent unnecessary evaporation of fluid (substitution material) filled in the flow path in the inkjet head communicating with the ejection port. It is installed when waiting for work.
After the capping unit is detached, the liquid material to be injected into the ink jet head is filled. The flow path in the ink jet head before filling with the liquid material is filled with a fluid different from the liquid material called a replacement material. As described above, the replacement material preferably has an action of dissolving the liquid material. In such a liquid material filling operation, the ejection port of the inkjet head is covered with a sucking / flushing unit, a negative pressure is applied, the replacement material in the inkjet head is sucked and discharged, and then the ink is similarly sucked. Is to be filled. That is, in a maintenance method for covering a nozzle of an inkjet head with a unit member and generating a negative pressure to suck a liquid, a waste liquid tank that communicates with the unit member and the negative pressure generation mechanism, and a low-viscosity liquid reservoir that communicates with the inkjet head An ink reservoir that communicates with the inkjet head, a liquid switching mechanism that selectively communicates the inkjet head with the low-viscosity liquid reservoir or the ink reservoir, and the low-viscosity liquid reservoir and the inkjet head An inkjet head characterized in that a negative pressure is generated in a unit member to fill the inkjet head with a low-viscosity liquid, and then the ink reservoir and the inkjet head are communicated to fill the inkjet head with ink. Implement maintenance methods.
After the liquid material to be ejected to the ink jet head is filled, the liquid material is ejected to a predetermined position different from the work, and it is confirmed whether the liquid material is reliably ejected (discarding operation). In particular, when the inkjet head has a plurality of injection ports, it is necessary to check whether the liquid material is injected from all the injection ports. In this confirmation operation, when the liquid material is not ejected from all the ejection ports, all the liquid material filled in the ink jet head is discharged and filled again. This is done by replacing the replacement material with a liquid material.
After refilling, it is discarded again and it is confirmed that the liquid material is injected from all the injection ports. When it is confirmed that the liquid material has been ejected from all the ejection ports, the inkjet head and the table on which the workpiece is placed are moved relative to each other, and the inkjet head is disposed at the application position on the workpiece to perform the application work. Do.

When a predetermined coating operation is completed, the work is discharged to a work storage device called an unloader. While the work is being discharged, the liquid material filled in the flow path in the ink jet is discharged to the ink jet head as described above, and the replacement material is filled. By this operation, the liquid material in the flow path of the inkjet head is replaced with the replacement material. In the case where the replacement material has an action of dissolving the liquid material, the liquid material is dissolved in the filled replacement material even if a little liquid material remains in the flow channel. The material does not solidify.
The filling of the replacement material is also to gently dissolve and clean the flow path in the inkjet head. After the replacement material filling operation is completed, the lower surface of the inkjet head is cleaned. The cleaning is preferably performed by the method using the cleaning liquid described in the first technical idea. When the nozzle cleaning is completed, the ink jet head is cleaned both inside and outside, and is in a clean state with no liquid material attached.
After cleaning is completed, a capping unit is mounted on the lower surface of the nozzle unit to prevent volatilization of the replacement material. The above process is repeated for each workpiece.

(4) Film formation method [i] Problem The conventional film formation method using an ink jet has the following two problems. One is a problem in the height direction (film thickness), and the other is a problem in the horizontal direction. The former is a problem that the coffee stain phenomenon in which the periphery of the edge of the film formation surface rises cannot be solved and the film cannot be formed with a uniform film thickness. The latter is a problem that bleeding occurs at the end (edge) of the film formation surface and a clear edge line cannot be formed.
Patent Document 4 discloses that the substrate is inclined at a predetermined angle in order to solve the problem that the film thickness of the alignment film is formed non-uniformly by connecting the droplets together. The problem of non-uniform film thickness has not been fundamentally solved.
The coffee stain phenomenon is a phenomenon observed in a low-viscosity solution and becomes fatal in the alignment film of the liquid crystal display element. In the case of an alignment film, since the main component polyimide is difficult to dissolve, the coffee stain phenomenon is caused because γ-butyllactone, N-methylpyrrolidone, butyl cellosolve, etc. are used in large quantities and spray-coated with low viscosity. Is likely to occur.

[Ii] Summary The inventor is able to form a film with a uniform film thickness when applied so that liquid flow does not occur, and when a plurality of droplets ejected from an ink jet head and landed on a work surface are combined, an edge line is formed. I found out that it oozes and created the 4th technical thought.
The fourth technical idea is that, after ejecting onto the workpiece by the first ejecting operation by the ink jet head, when ejecting to the position where it contacts or overlaps the droplet of the liquid material landed by the ejection, It is characterized by waiting for reaching a dry state (including a semi-dry state where the movement of the substance stops) such that the droplet does not flow, and then performing injection.
As described above, when the first droplet ejected on the workpiece by the first ejection operation is dried, the first droplet is ejected to the contact position or overlapping position after the second ejection operation. However, the second and subsequent droplets are not fluidly coupled on the workpiece. That is, since the droplets ejected by the first ejection operation (first droplets) are in a dry state, the droplets ejected after the second ejection operation (second droplets) There is no fluid coupling such as a phenomenon in which so-called droplets combine to form a single droplet by contact.
On the other hand, when the first droplet and the second droplet are fluidly coupled as in the prior art, the coffee stain phenomenon appears more prominently. The thickness of the film increases the thickness. That is, compared with the thickness difference between the film thickness of the central part of one drop and the film thickness of the edge before combining, the film thickness of the central part and the film of the edge part of the droplets formed by combining the liquid droplets The thickness difference becomes larger. However, when the droplets combine to form a single droplet, the height level becomes uniform due to the flow of the liquid material, so it is impossible to visually recognize the contact region or the overlapping region after the combination. .
In this respect, in the present technical idea, since the film is formed by drying for each injection operation, the thickness difference of the entire surface can be reduced as compared with the conventional technique in which fluid coupling occurs.

FIG. 12 is a comparison diagram between a conventional injection method in film formation and the method of the present invention. In FIG. 12, the upper figure (a) shows the conventional method which shows that the liquid material injected on the workpiece is joined and becomes uniform, and the lower figure (b) shows the first injection on the workpiece. A specific film forming method is illustrated in which each droplet of the ejected first droplet group is arranged apart from other adjacent droplets, and then ejected so as to fill the gap between the droplets. . In the lower figure (b), the second ejection that is ejected to the right with respect to the ejection position of the first droplet group, the third ejection that is ejected downward with respect to the ejection position of the first droplet group, A fourth ejection that is ejected to the lower right side with respect to the ejection position of the droplet group is performed. Here, also in the second injection, the third injection, and the fourth and subsequent injections, after the droplets formed by the injections of the respective previous steps are dried to a degree that can be suppressed, the subsequent steps are performed. Needless to say, the injection is performed.
Needless to say, the technical idea is not limited to the order of the injection positions illustrated in FIG. Any regular injection position may be used as long as the coating is uniformly performed on the entire surface of the workpiece by a plurality of injection processes (injection processes). Therefore, the number of injection processes may be 3 times or less, or 5 times or more. When the number of injection processes is increased and the coating amount per injection process is reduced, the unevenness on the surface of the workpiece is reduced. This is because there is a correlation between the unevenness of the workpiece surface and the coating amount. Further, reducing the coating amount has an effect of shortening the drying time.

  In addition, when the inkjet unit has a plurality of ejection openings, a plurality of droplets (first droplet group) ejected by the first ejection operation land at positions separated on the work, and the liquid enemy They do not touch each other. Even in this case, the same effect can be obtained by performing the plurality of droplets (second droplet group) ejected in the second ejection operation after drying to such an extent that the first droplet group does not flow. Needless to say.

The droplets on the workpiece may be dried naturally, but can be dried more quickly by raising the temperature of the table on which the workpiece is placed.
The temperature for drying the droplets is appropriately adjusted depending on conditions such as the type of liquid material, pitch, and injection amount. For example, the temperature from the experimental environment temperature (for example, 15 to 25 ° C.) to plus 150 ° C. The range is preferably set in the range from the experimental environmental temperature to plus 100 ° C., and more preferably in the range from the experimental environmental temperature to plus 50 ° C.
Also, the drying time for drying to the extent that the droplet does not flow is appropriately adjusted according to conditions such as stage temperature, type of liquid material, pitch, injection amount, etc., for example, about 20 to 100 seconds after landing It is preferable to set.

As described above, the film forming method of the present invention can reduce the amount of protrusion of the edge portion as compared with the conventional film forming method, so that it can be used for various applications including the formation of alignment films for liquid crystal display elements. Can be applied. The film forming method of the present invention is also suitable for forming a fine wiring pattern on a substrate as shown in FIG. That is, the conventional film formation method has a large amount of oozing and there is a risk that the wires may be connected to each other, so that a fine pattern could not be formed at a high density, but according to the film formation method of the present invention, Therefore, it is possible to form fine wirings with high density. This is because the amount of spread in the horizontal direction (horizontal direction) can be greatly reduced in the film forming method of the present invention (in Example 3 described later, the amount of spread is about 1 / compared to the conventional film forming method. 10). The film forming method of the present invention is particularly suitable for forming a thin film having a film thickness of several nanometers to several tens of micrometers.
Further, the film forming method of the present invention can easily control the film thickness. In the conventional film forming method, the liquid material after landing and the liquid material ejected next are combined to form uniform droplets and spread in the lateral direction (horizontal direction). It was difficult to control the thickness. In this respect, the film forming method of the present invention controls the number of depositions by increasing the film thickness by injecting and depositing the next liquid material on the liquid material that is not in a flow state after landing. Therefore, the film thickness can be easily controlled.

  Hereinafter, the details of the present invention will be described with reference to examples, but the present invention is not limited to the examples.

The cleaning mechanism of this embodiment includes a cleaning unit 2 having a function of spraying the cleaning liquid 12 to the inkjet head 10 and a function of spraying air.
FIG. 1a is an overall schematic plan view of an apparatus provided with the cleaning mechanism of this embodiment, and FIG. 1b is an overall schematic side view of the apparatus.
The apparatus of this embodiment is an inkjet coating apparatus that performs coating while relatively moving the inkjet head 10 and the work table 14 when positioned below the inkjet head 10.
The inkjet head 10 is attached to the beam 110 via a Z-axis moving mechanism 123 and an Hθ-axis rotating mechanism 125.
The work table 14 is a vacuum suction type work table. A temperature control option may be added to the work table 14.
Control of operations such as relative movement of the inkjet head 10 and work table 14 and cleaning of the inkjet head 10 can be performed from a personal computer (PC) 15 on an operation desk 16 installed beside the coating apparatus.

FIG. 2 is a schematic explanatory diagram showing one form of the cleaning mechanism of the present embodiment.
In FIG. 2, reference numeral 42 is compressed air from CDA (clean dry air), reference numeral 43 is a CDA suction opening / closing ball valve, reference numeral 44 is an exhaust air opening / closing ball valve, and reference numeral 45 is an exhaust filter (optional). ).
FIG. 3 is a schematic configuration diagram showing another form of the cleaning mechanism of the present embodiment.
The cleaning unit 20 is a component for preventing the cleaning liquid from splashing around when the inkjet head 10 is cleaned. The cleaning unit 20 is configured in a box shape or the like that is open so as to cover the nozzle surface of the inkjet head 10 and its periphery from below. The cleaning unit 20 is configured using, for example, stainless steel, Teflon (registered trademark), or the like because it is necessary to use a material that considers chemical resistance such as a cleaning liquid.
For the cleaning liquid, in order to completely wash the ink adhering to the nozzle surface of the inkjet head 10 and the periphery thereof, a colorless solvent having a factor that dissolves the ink (a main component solvent that dissolves the ink) is used. Used.

FIG. 4 a is a plan view showing the configuration of the cleaning unit 20, and FIG. 4 b is a side sectional view showing the schematic configuration of the cleaning unit 20.
The cleaning unit 20 is provided with an opening 28 at the center of the cleaner lip 23 that contacts the inkjet head 10, and a plurality of cleaning liquid supply ports 25 and a plurality of cleaning liquid recovery ports 26 are provided opposite to each other at the edge of the long side. It has been.
FIG. 5A is a diagram for explaining the cleaning. As shown in the figure, the cleaning unit 20 is brought into contact with the inkjet head 10, and the cleaning liquid is sprayed from the cleaning liquid supply port 25 to the vicinity of the outer peripheral end of the lower surface of the inkjet head 10 and recovered from the cleaning liquid recovery port 26 and the liquid receiving part 21. As a result, cleaning is performed.
FIG. 5B is a diagram for explaining the drying. As shown in the figure, after the cleaning is completed, the inkjet head 10 and the cleaning unit 20 are slightly separated (for example, 3 mm), and the cleaning liquid adhering to the inkjet head 10 is blown away by the air flowing through the gap between the inkjet head 10 and the inkjet unit 10. The head 10 and the cleaning unit 20 are dried. The cleaning unit 20 includes a bottom suction port 24, and the sucked waste liquid is stored in a waste liquid tank 40.
FIG. 6 shows a flowchart of the cleaning process and the drying process of the inkjet head 10 in the present embodiment outlined above.

By the way, when a negative pressure is generated in the cleaning unit 20, the adhesion between the lower surface (head surface) of the inkjet head 10 and the cleaning unit 20 is important. Here, if the inclination of the cleaning unit 20 with respect to the head surface is large, there is a problem that a gap is generated. Therefore, in this embodiment, it is possible to ensure the adhesion and sealing performance of the cleaning unit 20 by adopting a structure that can follow the inclination of the head surface. That is, by configuring the support member that supports the cleaning unit 20 with a soft elastic body, it has a degree of freedom to follow the inclination of the head surface and can maintain the sealing performance.
Further, the cleaning unit 20 has an opening / closing mechanism that makes it contact or non-contact with the inkjet head 10. The opening / closing mechanism can be configured by using a moving stage such as a manual type, a ball screw type, or a linear type that is generally used for raising and lowering. For example, a manufacturer of the moving stage includes Suruga Seiki Co., Ltd. and THK. The company's product is disclosed.

《Nozzle inspection mechanism》
The nozzle inspection mechanism of this embodiment is configured as shown in FIG.
First, the inkjet head 10 is moved to the inspection area where the inspection film is arranged. In the inspection area, the state of each inkjet nozzle of the inkjet head 10 is inspected.
In the inspection area, a transparent inspection film 72 that moves across the lower side of the inkjet head 10 is provided. The inspection film 72 is a film that is soluble in the actual liquid 71. The inspection film 72 is wound around a feed roller in a roll shape, and a new inspection film 72 can always be used for inspection by being wound up by a winding roller.
The landing droplet from the inkjet head 10 is imaged by the imaging device 74. The imaging device 74 can be configured by a generally known CCD camera or the like. FIG. 7A shows an aspect in which the imaging device is configured by two image recognition cameras (area sensors), and FIG. 7B shows an aspect in which the imaging device 74 is configured by a line sensor. Yes. In FIG. 7B, the recognizability is enhanced by using the reflected illumination 75 and the transmitted illumination 76 together. Which mode is selected is a design matter and is determined by factors such as the width of the inspection film 72 and the detection accuracy.
In the inspection film 72, when the actual liquid 71 has not landed or when the landing position is deviated from the predetermined position, the nozzle inspection mechanism displays error information that there is a defect such as nozzle clogging. .

FIG. 9 is a conceptual configuration diagram simplified for explaining the operation of the inkjet head 10. As shown in FIG. 9, the inkjet head 10 can selectively communicate the actual liquid (liquid material to be ejected) and the cleaning liquid via the liquid material switching unit 105.
Three units are arranged on the back side of the work table. From the left to the right in FIG. 9, the three arranged units replace the liquid material in the ink jet head flow path with the replacement material, or sucking that generates a negative pressure for replacing the replacement material with the liquid material. A flushing unit 102, a cleaning unit 20 that cleans the lower surface of the nozzle, and a capping unit 103 that caps the lower surface of the nozzle.

FIG. 10 is an explanatory diagram of the pretreatment operation of the inkjet head 10 in the configuration of FIG. The six diagrams shown in FIG. 10 will be described. In the switching unit 105, a solid line indicates a communication state, and a broken line indicates a blocking state.
[10-1] A diagram showing a state in which the capping unit 103 is attached to the lower surface of the inkjet head 10 and communicated with the cleaning liquid by the switching unit. It is a state at the time of application work standby.
[10-2] It is a diagram showing a state where the capping unit 103 is detached from the inkjet head 10 for the coating operation. The switching unit 105 is in a position where the inkjet head 10 and the cleaning liquid are communicated.
[10-3] It is a diagram showing a state where the inkjet head 10 is set in the sucking and flushing unit 102.
[10-4] After the inkjet head 10 is set in the sucking and flushing unit 102, the switching unit 105 switches to a position where the liquid material and the inkjet head 10 communicate with each other. Thereafter, by applying a negative pressure to the sucking and flushing unit 102, a liquid replacement operation (filling operation) in the inkjet head 10 is performed.
[10-5] FIG. 5 is a diagram showing that a discarding operation is performed on the sucking and flushing unit 102 after the liquid material is filled in the flow path of the inkjet head 10. This discarding is not an operation for confirming that the liquid material is reliably ejected from the inkjet head 10 by the imaging device or the sensing device, but a preliminary flow in which the liquid material in the flow path of the inkjet head 10 is performed before the main ejection operation. Work. When the confirmation work for the nozzle inspection is performed, it is preferable to perform the preliminary flow work in advance. Of course, the injection in the confirmation operation can also serve as a preliminary fluid operation.
[10-6] It is a diagram showing a state in which the coating operation is performed while moving the inkjet head 10.

FIG. 11 is an explanatory diagram of the post-processing operation of the inkjet head 10 in the configuration of FIG. Six figures shown in FIG. 11 will be described.
[11-1] A state in which the inkjet head 10 moves onto the sucking / flushing unit 102 after the application work is completed.
[11-2] FIG. 11 is a diagram showing a state where the inkjet head 10 is set in the sucking / flushing unit 102 and the liquid material switching unit 105 is switched to a position where the inkjet head 10 communicates with the cleaning liquid.
[11-3] FIG. 11 is a diagram illustrating a state where the liquid replacement operation in the inkjet head 10 is completed and the inkjet head 10 is detached from the sucking / flushing unit 102.
[11-4] It is a diagram showing that the inkjet head 10 is set in the cleaning unit 20 and a cleaning operation is performed. The liquid material switching unit 105 holds a position where the inkjet head 10 and the cleaning liquid communicate with each other.
[11-5] It is a diagram showing that the inkjet head 10 moves onto the capping unit 103 after the cleaning step.
[11-6] It is a diagram showing that the capping unit 103 is mounted on the lower surface of the inkjet head 10. By mounting the capping unit 103, the injection port can be kept clean, and unnecessary evaporation of the replacement material filled in the flow path in the inkjet head 10 can be prevented.

FIG. 14 is a configuration diagram of a maintenance mechanism of the ink jet coating apparatus according to the present embodiment.
The inkjet head 10 has a plurality of nozzles 6 and performs printing or the like by discharging ink 2 stored in a first tank 12 communicated by a communication member 9. Maintenance of the inkjet head 10 is performed by covering the nozzle 6 with the sucking / flushing unit 102, generating a negative pressure in the sucking / flushing unit 102, and waste liquid in which the sucked ink is communicated with the sucking / flushing unit 102 through the communication member 9. This is done by discharging to the tank 40. The contact between the sucking / flushing unit 102 and the inkjet head 10 is automatically performed by the opening / closing mechanism 7. The opening / closing mechanism 7 may be a mechanism that relatively moves the inkjet head 10 or a mechanism that relatively moves the sucking and flushing unit 102. Depending on the industrial field, the sucking / flushing unit 102 may be manually opened and closed.

  In the maintenance mechanism of the present embodiment, the above-described publicly-known configuration has the second tank 13 communicated with the inkjet head 10 by the communication member 9 and the communication between the inkjet head 10 and the first tank 12 or the second tank 13. And a liquid switching unit 105 that selectively switches between them. The second tank 13 stores a cleaning liquid 3 that is a low-viscosity liquid that flows first when maintenance starts. In this embodiment, a solvent that dissolves the ink 2 is used as the cleaning liquid 3. Thereby, even when the ink 2 is consolidated in the flow path, it can be dissolved.

Further, as shown in FIG. 15, the sucking / flushing unit 102 of the present embodiment is configured to have a degree of freedom to follow the inclination of the head surface.
The contact member 61 that contacts the head surface is made of rubber having a Shore A hardness of 40 to 80 degrees (preferably 50 to 70 degrees) (JIS K 6253 standard), which is a hard elastic body, It is attached by screwing.
The frame 62 is supported by a support member 63 composed of a soft elastic member (for example, rubber or spring) fixed by bonding or screwing. The support member 63 preferably has a penetration of 40 to 80 (preferably 50 to 70 degrees) so that it can follow an attachment error (three-dimensional inclination) of the nozzle surface of the inkjet head 1. The support member 63 is fixed to the plate-like attachment member 64. A joint 66 that can connect the communication member 9 to the bottom suction port 24 that is at least one suction through hole is disposed on the bottom surface of the frame 62.
According to the sucking and flushing unit 102 of the present embodiment configured as described above, complete adhesion and sealing can be ensured without being affected by the inclination of the nozzle surface.

The negative pressure generating mechanism of the present embodiment includes a signal generating device 8, a pressure supply pump 19, a regulator 38, and an ejector 37, and communicates with the sucking and flushing unit 102 via a waste liquid tank 40. A silencer that absorbs air sound may be added to the negative pressure generating mechanism.
The signal generator 8 can set and register signal waveforms of time and voltage of a plurality of patterns, and can select and output only one pattern from a plurality of registered patterns. The regulator 38 can supply pressure according to the voltage of the signal waveform of the signal generator 8. The signal generator 8 may be constituted by, for example, a pulse generator or a PC.
The ejector 37 can generate a negative pressure according to the pressure supplied from the regulator 38. The regulator 38 and the ejector 37 can be configured by commercially available pneumatic equipment.
Even if the negative pressure generated by the ejector 37 is not controlled by the regulator 38, the negative pressure is controlled by adjusting the throttle amount of the throttle valve provided on the disposal side of the ejector 37 while maintaining a constant pressure from the regulator 38. May be.

The negative pressure generating mechanism of this embodiment is characterized in that the negative pressure generated in the sucking / flushing unit 102 is gradually returned to atmospheric pressure. That is, in this embodiment, it is possible to prevent the re-mixing of bubbles by causing the negative pressure in the sucking / flushing unit 102 to be gently generated by the signal generator 8 that generates a preset signal waveform. It was.
As long as the negative pressure in the sucking / flushing unit 102 changes slowly, the signal waveform to be set may be linear or curved, or may be a signal waveform that changes in a fine stepwise manner. . An example of the curved waveform is a Sin waveform as shown in FIG. As shown in FIG. 16A, when the signal waveform output from the signal generator 8 is a Sin waveform, the pressure supplied from the regulator 38 changes as shown in FIG. The pressure becomes as shown in FIG. 16C, and it is possible to prevent the meniscus at the tip of the nozzle 6 of the inkjet head 10 from being vibrated.

The coating control method in the present embodiment is carried out according to the procedure shown in the flowchart in the left diagram of FIG. First, the liquid material coating apparatus is turned on (started), and the liquid material coating apparatus performs an initialization operation (initial operation). After this, the device parameters for the product (product type) to be produced are set (data setting). The apparatus parameters are a work size, a coating area, an injection condition, and the like. Once these are complete, you are ready to do production.
Next, the workpiece is supplied from a workpiece supply device called a loader to the stage of the liquid material application device. After the work placed on the stage is positioned on the stage, the application position on the work is confirmed, and the relative displacement between the liquid material application device and the application position on the work is corrected (alignment). This correction is performed by subjecting the work position to an image pickup device such as a CCD camera and image processing of the picked-up image. At this time, in addition to physical correction for rotating the stage, program correction for correcting the coordinate position of the program related to the movement of the robot is performed. With the processing up to this point, preparations for correctly applying to a predetermined application position on the workpiece positioned on the table of the apparatus are completed. When the above correction processing is completed, the coating operation is started.

The film forming method of the present embodiment is an ink jet coating method in which a film is formed by ejecting and landing the next droplet after drying to such an extent that the landed liquid does not flow. A polyimide solution was used as the liquid material, and a glass substrate was used as the substrate.
The polyimide solution is for forming a semiconductor insulating layer or a liquid crystal panel insulating film. The glass substrate was placed on a temperature-adjustable stage in order to dry the landed liquid material so as not to flow.
[Comparative example]
When a conventional ink jet coating method was applied to a 25 mm square coating area at 30 pl / drop and a 70 micron pitch, the following situation was observed.
(A) Lateral direction (horizontal direction): The outer periphery spread about 0.5 to 1.0 mm with respect to the prescribed application area.
(B) Longitudinal direction (height direction): It was 80 to 85 nm at the center of the application area, and about 1000 nm at the edge.

[Example 3]
When the same application area of 25 mm square was applied with 8 pl / droplet, 4 times, and 70 micron pitch by the ink jet application method of this example, the following situation was obtained.
(A) Lateral direction (horizontal direction): The outer circumference spread about 0.05 to 0.1 mm with respect to the prescribed application area.
(B) Longitudinal direction (height direction): It was 80 nm to 100 nm in the central portion of the application area, and was about 80 nm to 100 nm in the peripheral portion.
As described above, it was confirmed that the film forming method of this example had an advantageous effect as compared with the conventional film forming method shown in the comparative example. More specifically, the method of this embodiment can reduce the unevenness formed in the film, reduce the height difference of the entire film surface, and reduce the amount of protrusion of the edge portion. I was able to confirm.

The present invention is not limited to an ink jet printer, and can be applied to various ink jet recordings such as a precision spray / injection device (including a coating device), a precision coating device, and the like. Ink-jet patterning, for example, printing on organic EL display panels and large color panels, and application to a coating device, a drawing device, and a printing device for industrial marking, etc. are also possible.
The ink jet recording method can be applied regardless of a mechanical conversion method such as a piezo method and a bubble generation method such as a resistance heating jet method.
It can also be used in the lens coloring process in the lens manufacturing industry, and in posters and building material decoration in the large printing industry.

Claims (9)

An inkjet film forming method for forming a film by a plurality of injection processes,
After the second ejection operation, when a droplet is ejected to a position where it touches or overlaps a droplet landed by the preceding ejection operation, a dry state is reached such that the droplet on the workpiece does not flow. Ink-jet film forming method characterized by performing injection after waiting.   The inkjet film forming method according to claim 1, wherein in the first ejection operation, each droplet of the ejected droplet group is disposed separately.   3. The ink jet film forming method according to claim 1, wherein the time for drying the droplets on the work is shortened by increasing the temperature of the table on which the work is placed.   4. The inkjet film forming method according to claim 1, wherein the film formation is performed by an inkjet head having a plurality of ejection ports.   The inkjet film-forming method according to claim 1, wherein the number of spraying steps is increased and the amount of spraying is reduced.   6. The ink jet film forming method according to claim 1, wherein the wiring pattern is formed by a film.   The liquid droplet is ejected to a position in contact with or overlapping with the liquid droplet after waiting for 20 to 100 seconds from the landing of the liquid droplet by the preceding ejection operation. Inkjet film forming method.   8. The ink-jet film forming method according to claim 1, wherein the film thickness of the formed film is several nm to several tens of μm.   An inkjet coating apparatus that performs coating while relatively moving an inkjet head and a work table positioned below the inkjet head, wherein the control apparatus executes the inkjet film forming method according to any one of claims 1 to 8. Inkjet coating device.