TWI556869B - Method and apparatus for inspecting ink jet nozzles - Google Patents

Description

Inkjet nozzle inspection method and device

The present invention relates to a cleaning method, a nozzle inspection method, a coating control method, and a film formation method of an inkjet coating apparatus including an ink jet recording head (hereinafter referred to as "inkjet head"), and more particularly to A cleaning method, a nozzle inspection method, a coating control method, and a film formation method for removing dirt, debris, impurities, and the like adhering to the nozzle surface of the inkjet head and its periphery.

In addition, the inkjet head in this specification is mentioned before it is not specifically stated, and is an inkjet head which has a single or a multiple nozzle.

In the ink jet recording apparatus, in order to maintain high quality recording quality, it is necessary to remove ink, impurities, and the like remaining on the ink discharge surface of the ink jet recording head.

Patent Document 1 discloses a method in which a wiping blade is opposed to an ink ejection surface of a head and is cleaned by a wiping operation. In order to improve cleaning performance, the material, angle, and contact method of the wiping blade are reduced. .

According to Patent Document 2, an ink absorbing slit is provided on the downstream side of the squeegee cleaning return operation direction with respect to the discharge port, and the ink scraped by the squeegee is provided in a slit shape parallel to the plurality of discharge ports. The ink absorption slit of the suction port, the method of sucking the above ink to improve performance, and the like.

Patent Document 3 discloses that after the nozzle surface is blown from the nozzle of the atomizer to the nozzle of the ink jet head and the periphery thereof, the nozzle attached to the ink jet head is attached. The cleaning liquid around it and the surrounding liquid are scraped by a squeegee.

The droplet discharge method of the alignment film disclosed in Patent Document 4 is such that an inkjet head having a plurality of nozzles arranged at a predetermined pitch relatively moves the substrate, and droplets of the alignment film are ejected from the nozzle onto the substrate. In the method, the direction in which the inkjet head moves relative to the substrate is inclined at a predetermined angle in a direction in which the pixels are arranged in a lattice shape in the substrate.

The film forming apparatus disclosed in Patent Document 5 includes: a head supporting structure having a single or a plurality of ink jet ‧ heads each having a plurality of nozzles arranged at a predetermined interval; and having a plurality of nozzle array directions a substrate transfer mechanism of the substrate transfer platform that can move relative to the plurality of nozzles in the orthogonal direction; and the film forming solution is sprayed from the plurality of nozzles on the surface of the substrate mounted on the substrate transfer platform A non-contact film forming apparatus that performs coating and forms a film, and is characterized in that it is provided with at least a substrate transporting platform, an ink jet ‧ head, and the head supporting structure as a spray coating film forming chamber And a vacuum decompression means for performing a pressure reduction inside the vacuum chamber in order to perform a spray coating film formation under a reduced pressure environment.

The method for forming an alignment film according to Patent Document 6 includes: an inspection step of inspecting an abnormality of the inkjet nozzle by dropping a film of the alignment film by a droplet using an inkjet nozzle; When it is determined in the inspection step that the droplet pattern is within a predetermined range, the inkjet is opposed to the substrate, and the alignment film material is droplet-formed by the inkjet nozzle, and the droplet is formed on the substrate. Film forming step of the film.

The method for manufacturing an apparatus disclosed in Patent Document 7 includes a method of manufacturing a device including a step of forming a pattern forming region of a substrate and discharging a liquid material from a droplet discharge head; It is characterized by comprising a rinsing step of discharging the liquid material to a predetermined region other than the pattern forming region.

(Patent Document 1) Japanese Patent Laid-Open Publication No. 2004-291364

(Patent Document 2) Japanese Patent Laid-Open Publication No. 2004-42571

(Patent Document 3) Japanese Patent Laid-Open Publication No. 2002-19132

(Patent Document 4) Japanese Patent Laid-Open Publication No. 2006-320839

(Patent Document 5) Japanese Patent Laid-Open Publication No. 2006-289355

(Patent Document 6) Japanese Patent Laid-Open Publication No. 2006-058772

(Patent Document 7) Japanese Patent Laid-Open Publication No. 2003-282245

An object of the present invention is to provide a cleaning method, a nozzle inspection method, a coating control method, and a film formation method of an inkjet coating device which can solve the technical problems described later.

A cleaning method for an ink jet head according to a first aspect of the present invention, characterized in that a cleaning region of the ink jet head is covered by a unit member having a cleaning liquid supply port and a suction port, and suction is generated from the suction port. The force is applied to the washing liquid supply port facing the suction port, and the washing liquid is sprayed toward the washing area to be washed.

According to a second aspect of the invention, in the first aspect of the invention, after the cleaning, the ink jet head and the unit member are slightly separated, and the cleaning region of the ink jet head is dried by applying a suction force to the unit member.

According to a third aspect of the invention, in the first or second aspect of the invention, the liquid is a liquid composed of a solvent having a factor for dissolving the liquid material.

A method of inspecting an ink jet head according to a fourth aspect of the invention is directed to a nozzle provided from an ink jet head The ejected liquid material is dropped onto the inspection member, and the nozzle abnormality is inspected according to the droplet pattern of the drop; wherein the inspection member is reflected by the liquid drop and the non-drop drop. The composition of the materials of different rates.

According to a fourth aspect of the invention, the inspection member is a film that is dissolved by dropping of a liquid material.

In the inkjet coating control method according to the sixth aspect of the invention, after the discharge operation from the inkjet head, the liquid material for discharge filled in the flow path in the ink jet head is replaced with a low-volatility replacement material, and The replacement material is again replaced with the liquid for discharge before the start of the discharge operation.

According to a seventh aspect of the invention, in the sixth aspect of the invention, the liquid is composed of a solvent having a factor for dissolving the liquid material.

The inkjet film forming method according to the eighth aspect of the invention is directed to a film forming machine by a plurality of spraying steps; wherein, after waiting for the liquid droplets on the workpiece sprayed from the previous step to be dried to a degree of no flow, the liquid material is brought into contact or Partially overlapping the position of the liquid droplets dropped by the previous step.

The ninth invention is the eighth invention, wherein the number of times of the spraying step is increased, and the amount of injection per one time is reduced.

A tenth invention is the invention of claim 8 or 9, wherein the wiring pattern is formed of a film.

(1) In the cleaning of the ink jet head, since the solid matter such as the squeegee does not contact the nozzle of the ink jet head and its periphery, the ink jet head can be cleaned without wearing dust.

Further, since the cleaning liquid is used, it is possible to wash with a strong cleaning power even when the liquid material such as ink is dried.

Furthermore, it has the feature that the work time can be shortened and the production can be made inexpensively.

(2) It is possible to detect the nozzle failure of the ink jet head with high visibility, and in particular, the visibility can be remarkably improved in the transparent liquid material.

(3) Solving the problem of coating control of the ink jet head, and performing a stable discharge operation. In particular, it has a higher effect on highly volatile liquid materials.

(4) In the film formation by ink jet, the difference in thickness of the entire surface can be reduced as compared with the conventional method.

1, 10‧‧‧ inkjet nozzle

2‧‧‧Ink

3‧‧‧washing liquid

4‧‧‧Used cleaning solution (waste liquid)

5‧‧‧ Negative pressure

6‧‧‧ nozzle

7‧‧‧Opening and closing institutions

8‧‧‧Signal generator

9‧‧‧Connected components

11‧‧‧Liquid spit surface

12‧‧‧1st slot

12a, 12b‧‧‧Liquid bottles

13‧‧‧2nd slot

13a‧‧‧washing liquid bottle

14‧‧‧Workpiece platform

15‧‧‧Personal Computer (PC)

16‧‧‧ operation table

19‧‧‧Pressure supply pump

20‧‧‧cleaning unit

21‧‧‧Liquid Department

22‧‧‧Drain valve

23‧‧‧ Cleaning the lips

24‧‧‧ bottom suction port

25‧‧‧Clean solution supply port

26‧‧‧ Washing liquid recovery port

28‧‧‧ openings

31a, 31b‧‧‧ Washing liquid nozzle solenoid valve

32a, 32b‧‧‧ side nozzle atmospheric open valve

33‧‧‧Supply valve

34a, 34b‧‧‧ solenoid valve for negative pressure

35‧‧‧Cleans supply valve

36‧‧‧Material switching valve

37‧‧‧Injector

38‧‧‧Regulator

40‧‧‧ Waste tank

41‧‧‧Manual connector

42‧‧‧Compressed air

43‧‧‧CDA suction opening and closing ball valve

44‧‧‧Exhaust air opening and closing ball valve

45‧‧‧Exhaust filter

51‧‧‧Open and close solenoid valves

52‧‧‧Full sensor

61‧‧‧Abutment components

62‧‧‧Frame

63‧‧‧Support members

64‧‧‧Installation components

66‧‧‧Connectors

71‧‧‧Official liquid

72‧‧‧Inspection film

73‧‧‧ boards

74‧‧‧ camera

75‧‧‧Reflective lighting

76‧‧‧through lighting

77‧‧‧Vision of the camera

78‧‧‧The official liquid of the drop

81‧‧‧Feed roller

82‧‧‧Winding rolls

101‧‧‧Inkjet nozzle control box

102‧‧‧Absorption/rinsing unit

103‧‧‧ sprinkler cover unit

104‧‧‧Image camera

105‧‧‧Liquid material switching unit

106‧‧‧Inkjet control board

107‧‧‧Liquid tank

108‧‧‧Emergency switch

109‧‧‧floor

110‧‧‧ beams

112‧‧‧Various air compressors

113‧‧‧Instrument box

114‧‧‧Control box

121‧‧‧X-axis moving mechanism

122‧‧‧Y-axis moving mechanism

123‧‧‧Z-axis moving mechanism

124‧‧‧θ axis rotation mechanism

125‧‧‧Hθ axis rotation mechanism

151‧‧‧1st valve

152‧‧‧2nd valve

Fig. 1a is a schematic overall plan view of an apparatus including the cleaning mechanism of the first embodiment.

Fig. 1b is a schematic overall side view of a device equipped with the cleaning mechanism of the first embodiment.

Fig. 2 is a schematic explanatory view showing a form of a cleaning mechanism of the first embodiment.

Fig. 3 is a schematic structural view showing another embodiment of the cleaning mechanism of the first embodiment.

Fig. 4a is a plan view showing the structure of the cleaning unit of the first embodiment.

Fig. 4b is a side cross-sectional view showing the schematic structure of the cleaning unit of the first embodiment.

Fig. 5 (a) and (b) are explanatory views of a washing step and a drying step performed by the washing unit of the first embodiment.

Fig. 6 is a flow chart showing the steps of washing and drying of the ink jet head of the first embodiment.

7(a) and 7(b) are explanatory views of the nozzle inspection mechanism of the first embodiment.

Fig. 8 is a flow chart showing the execution sequence of the coating control of the ink jet head.

Fig. 9 is a schematic conceptual view showing the operation of the ink jet head.

Fig. 10 is an explanatory view showing the processing operation of the ink jet head of the structure of Fig. 9;

Fig. 11 is an explanatory view showing the post-processing operation of the ink jet head of the structure of Fig. 9.

12(a) and (b) are explanatory diagrams for comparison between a conventional thick film forming method and a thick film forming method of the present invention.

Figure 13 is a wiring pattern which can be formed by the film forming method of the present invention.

Fig. 14 is a structural view showing a maintenance mechanism of the second embodiment.

Figure 15 is a perspective side view of the suction/rinsing unit of Embodiment 2.

16(a) to (c) are signal waveforms outputted from the machine of the second embodiment.

The present invention is based on the following four technical ideas related to an inkjet coating apparatus.

(1) Cleaning method and mechanism

[i]Question

A problem of the first technical idea is to improve the ability to remove droplets adhering to the ejection surface of the ink jet head.

Furthermore, since the size of the conventional cleaning mechanism is large, the goal of further miniaturization is also a problem to be solved.

Furthermore, it is a problem to be solved if the cleaning is not performed using a rigid blade. The reason is that if the squeegee is brought into contact with the nozzle of the ink jet head or its peripheral portion, there is a problem that abrasion dust is generated. When abrasion dust is generated, it becomes a cause of nozzle clogging, which causes a problem of contamination of the surrounding environment. In addition, if there is a possibility of wearing dust, the use in a clean room is limited.

[ii] Subject

In order to remove the liquid material adhered to the ejection surface of the inkjet head, the adhered liquid material is brought into contact with the cleaning liquid (cleaning agent) which dissolves the liquid material, and it is effective to dissolve the liquid material by the cleaning liquid.

Further, it is important to form an ejection opening for ejecting the liquid material on the above-mentioned emitting surface, and it is important to bring the periphery into contact with the cleaning liquid without any omission. This is particularly important in the case of an ink jet head having a plurality of injection ports on the exit surface.

The first technical idea is a cleaning liquid supplied from one end of the ejection surface of the ink jet head. The surface of the exit surface flows and is recovered from the end farthest from the supply of the cleaning liquid. The liquid material adhered to the emitting surface is dissolved from one end of the emitting surface by using the cleaning liquid, and flows to the opposite end of the emitting surface, whereby the emitting surface can be cleaned without any omission and efficiency.

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 recovered from a plurality of positions at the opposite ends. Here, the number of positions in which the cleaning liquid is supplied does not need to be the same as the number of positions in which the cleaning liquid is recovered.

More preferably, the cleaning liquid is supplied from one end of the longitudinal direction side of the ejection surface of the ink jet head, and the cleaning liquid is recovered from the opposite end of the same emission side in the longitudinal direction side. The reason is that the flow distance of the cleaning liquid on the ink ejection surface can be shortened, and the cleaning efficiency can be improved.

For example, an ink jet head having a plurality of ejection orifices is also effective for a unit having a large size.

Further, the washed exit surface is wetted by the cleaning liquid, but it is preferable to perform drying in order to shorten the standby time. The drying means of the washed exit surface is preferably natural drying or blow drying because the exit surface is prevented from being contaminated.

As described above, if no droplets adhere to the ejection surface of the ink jet head, the accuracy of the amount of droplets ejected from the ink jet head and the accuracy of the drop position of the droplets on the workpiece are improved.

A preferred embodiment of the cleaning solution is composed of a colorless solvent having a factor for dissolving the ink (for example, a solvent which dissolves the main component of the ink).

However, inks generally used in ink jet printers can be classified into dye systems or pigment systems. The term "dye" refers to a coloring agent that disperses or fuses molecules using a carrier medium. The carrier medium is liquid or solid at room temperature. The carrier medium typically employed is water, or a mixture of water and an organic cosolvent. Generally, it is mainly composed of water, and contains a coloring agent, and contains glycerin, etc. for the purpose of preventing clogging or the like. Wetting agent. When the carrier medium is water, the ink generally has the disadvantage of low water fastness.

The term "pigment" refers to a coloring agent which is insoluble in a carrier medium but is dispersed or suspended in the form of small particles, and is usually stabilized by the use of a dispersing agent in order not to cause aggregation and precipitation. Many of such compounds are conventionally used. For example, a pigment such as an organic pigment or carbon black is micronized by using a surfactant or a dispersing agent, and a pigment ink or the like as a coloring agent is used by being dispersed in a medium such as water.

The technical idea is irrelevant to dye systems or pigment systems. The viscosity of the ink is mainly low-viscosity of several tens of cps, but it can also be applied to a medium viscosity of several hundred cps or more on the premise that it can be sprayed.

In addition, the present technical idea can be applied to functional inks such as wiring pattern printing of a printed substrate, application of a lubricant to a minute part, or printing of an outdoor light-resistant display material, UV (Ultraviolet) hardening ink printing, and the like. .

[iii] Implementation order

The cleaning of the inkjet head is performed in the order of steps A to D (refer to Fig. 6). In addition, "B. washing operation" is an example of the sequence of the structure shown in FIG.

"A. Disposal of the cleaning mechanism by the inkjet nozzle"

The ink jet head 10 is brought into contact with the cleaning unit 20 of the cleaning mechanism. In other words, 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 which is provided in a concave shape at the center of the cleaning unit 20. The cleaning lip 23 serves as a contact surface between the lower surface of the ink jet head 10 and the upper surface of the cleaning unit 20.

"B. Washing operations"

1) The cleaning liquid nozzle solenoid valves 31a and 31b are opened to communicate with the flow paths connected via the electromagnetic valves 31a and 31b.

2) The side nozzle air opening valves 32a and 32b are blocked from communicating with the atmosphere, and are located at a position in communication with the flow path via the open valves 32a and 32b. (The cleaning unit 20 is connected to the solenoid valve 31a by the open valve 32a, and the solenoid valve 31b is connected to the discharge valve 22 by the open valve 32b.)

3) The ejector 37 is connected to the liquid receiving portion 21 of the cleaning unit 20 by the discharge valve 22, and the negative pressure electromagnetic valves 34a and 34b are opened.

4) By the step up to the above 3), a negative pressure is applied to the flow path ejector 37 of the cleaning unit 20, and the washing liquid stored in the cleaning liquid bottle 13a is supplied to the washing unit 20.

5) The cleaning liquid supplied to the cleaning unit 20 is supplied from the cleaning liquid supply port 25 to the ink jet 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 under the ink jet head 10 flows under the ink jet head 10, and the cleaning liquid recovery port 26 is formed from the vicinity of the opposite end to the cleaning liquid supply side below the ink jet 10. Then, it is recovered again in the cleaning unit 20, or before it reaches the cleaning liquid recovery port 26, it is separated from the lower surface of the inkjet head 10, and is recovered in the liquid receiving portion 21 of the cleaning unit 20. The liquid receiving portion 21 communicates with the discharge valve 22, and the discharge valve 22 is located at a position where the other flow path passing through the discharge valve 22 is blocked from the communication between the liquid receiving portion 21, and thus is left in the liquid receiving portion 21 to be washed. liquid.

The cleaning liquid that has flowed into the cleaning unit 20 from the cleaning liquid recovery port 26 is recovered in the waste liquid tank 40 via the discharge valve 22 and the ejector 37.

7) After sufficiently performing the washing, the cleaning liquid nozzles 31a, 31b are closed, and the negative pressure solenoid valves 34a, 34b are closed, and the side nozzle atmosphere opening valves 32a, 32b are placed. In a position that communicates 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. Disengagement of self-cleaning mechanism of inkjet nozzle"

The ink jet head 10 is placed under the cleaning unit 20 to form a gap between the lower surface of the ink jet head 10 and the upper surface of the cleaning unit 20. This gap is set to the distance at which the appropriate airflow is generated based on the drying operation to be performed next.

"D. Drying operation"

1) In order to communicate the waste liquid tank 40 with the washing unit 20, the discharge valve 22 is switched, and the negative pressure electromagnetic valves 34a, 34b are opened.

2) Thereby, the liquid receiving portion 21 of the cleaning unit 20 communicates with the waste liquid tank 40, and a negative pressure is applied to the liquid receiving portion 21, so that the washing liquid stored in the liquid receiving portion 21 faces the waste liquid tank. 40 flows, and the washing liquid which becomes waste liquid is recovered by the waste liquid tank 40.

3) Further, a gap is provided between the lower surface of the ink jet head 10 and the upper surface of the cleaning unit 20, and an atmosphere that counteracts the negative pressure of the liquid receiving portion 21 flows into the liquid receiving portion 21 from the gap. The atmosphere flowing in the gap has a function of causing the cleaning liquid droplets attached to the lower surface of the inkjet head 10, and the dropped cleaning droplets fall on the liquid receiving portion 21 and are recovered by the waste liquid tank 40. Alternatively, the air flow (negative pressure) can be adjusted by adjusting the distance between the lower surface of the ink jet head 10 and the cleaning unit 20.

4) After the washing liquid stored in the liquid receiving portion 21 is recovered through the waste liquid tank 40, the air flowing in the gap has an effect of drying the lower surface of the ink jet head 10 while maintaining the state. An injection port for ejecting the liquid material is formed under the ink jet head 10, and since the lower surface can be dried without being in contact with other substances, the ejection port can be maintained in an extremely clean state.

5) After the ink jet head 10 is sufficiently dried under the lower surface, the negative pressure solenoid valves 34a, 34b are used. The action is generated to be in the closed position, and the supply of the negative pressure to the liquid receiving portion 21 by the cleaning unit 20 is stopped.

6) Then, the supply valve 33 is actuated, and the ink jet head 10 is connected to the liquid material bottles 12a and 12b, and the liquid material flow path is integrated into a state in which the liquid material can be supplied to the ink jet head 10.

[iv]effect

According to the first technical idea described above, since the cleaning is performed by the cleaning liquid, abrasion dust does not occur.

Further, since the principle of injecting the cleaning liquid by the action of the negative pressure is applied, the cleaning liquid is not supplied if the ink jet head is not closely attached to the cleaning unit. Therefore, even if the ink jet head is separated from the cleaning unit, the supply of the cleaning liquid can be stopped by vacuum destruction, and the occurrence of spraying the cleaning liquid outside the cleaning unit can be prevented.

Further, since the drying operation is also performed by the negative pressure action, it is possible to prevent the outside of the washing unit from being contaminated by the washing liquid.

(2) Nozzle inspection method and mechanism

[i]Question

Since the conventional inkjet coating apparatus is an ink system, there is a problem in that it is impossible to appropriately apply a necessary amount of droplets to a necessary place due to a nozzle failure, a nozzle orientation, a nozzle being clogged with a liquid material, or the like.

Further, as disclosed in Patent Document 6, in the inspection method performed by dropping the liquid material on the film for inspection, since the shape of the liquid droplets collapses after reaching the image recognition camera after the dropping, even Image recognition of the shape of the droplets is still impossible to perform accurately.

[ii] Subject

The second technical idea is as disclosed in Patent Document 6, and the nozzle inspection is performed by dropping a liquid material onto a member for inspection (dropping matter). The difference from Patent Document 6 is that it does not focus on the liquid material (droplet) to be applied, but on the portion of the drip-containing material that is applied through the liquid material, in comparison with other portions.

In the preferred embodiment of the present invention, the drip material is composed of a film for inspection having a soluble material. Thereby, even in the case of the transparent liquid material having poor visibility, the drop portion of the liquid material is dissolved, and the film for inspection is turbid (transparency is changed or opaque). Therefore, by improving the visibility of the drop, it is easy to detect the drop. In particular, the effect is more pronounced when using a highly transparent liquid material.

The drop of the liquid material is appropriately selected in accordance with the liquid material to be ejected, and the emphasis is on the reflectance of the drop portion of the liquid material. If the drip of the drip is dissolved, the reflectance is changed by the reflection or the like, so that the drop can be taken by the image processing precision. It may be a combination of the drip substance and the liquid material which change the reflectance by the drop, or may be a state in which the liquid material penetrates into the drip. The liquid material infiltrates into the drip-containing material, and is particularly effective as a liquid material which is not mainly a solvent (for example, a liquid material which uses water as a solvent).

The drip is preferably dissolved (or infiltrated) rapidly at the instant when the liquid drops. The reason is that if the liquid material falling on the drip-containing material is held for a long time, the diameter of the drop mark is enlarged. It is preferable not to use a material which is diffused or dissolved, but to use a material which is dissolved (or infiltrated) into a material which penetrates downward. For example, a liquid material containing toluene as a solvent is preferably a polystyrene film. The drip is preferably set so as not to be dissolved by the falling of the liquid material to the thickness of the back side of the drip.

The drip is preferably transparent, but it does not necessarily have to be transparent or colored. The focus is on the identification of the drop and non-drop portions. The drip is of course composed of a single material, but covers those whose surface is coated and which is layered by a plurality of films.

As the liquid material that is dropped by the dropping object, a sensing device such as an image pickup device such as a CCD (Charge-coupled Device) camera or a laser sensor can be used.

For example, the image processing system performs edge extraction or binarization for the image of the imaging field covering the drop, thereby taking the drop.

[iii] Implementation order

The procedure for checking the nozzle will be described with reference to the sequence of the structure shown in Fig. 7(a).

1) The winding roller 82 is rotated to place a new inspection film 72 under the inkjet head 10. Here, the inspection film 72 located under the inkjet head 10 is positioned by the plate 73 to accurately maintain the distance from the inkjet head 10.

2) The official liquid 71 is discharged from the inkjet head 10 and dropped onto the inspection film 72. The film for inspection 72 is dissolved by the dropping, leaving a trace of the drop.

3) The winding roller 82 is rotated, and the dropping position of the inspection film 72 is positioned above the image pickup device 74.

4) The inspection film 72 is imaged by the imaging device 74. In addition, the imaging of the imaging device 74 may be performed after the inspection film 72 is stopped, or may be performed while the inspection film 72 is being moved.

5) The state of the inkjet head 10 is checked based on the image data acquired by the image pickup device 74. From the "drop" and "diameter" of the drop marks, the blockage can be checked, and the deviation from the drop position can be checked for poor dispersion.

(3) Coating control method

[i] question

The problem is that it is possible to achieve a desired accuracy by realizing a stable ink discharge operation by preventing a problem such as clogging of the nozzle of the ink jet head.

When the liquid material discharge operation is stopped, the flow path near the injection port of the ink jet head is dried, because The viscosity of the liquid material is precipitated from the solid content of the liquid material, and clogging occurs, and the flying material of the discharged liquid material is bent, which causes a problem that the stable discharge operation cannot be performed.

Further, if the discharge stability of the liquid material is deteriorated, there is a problem that it is impossible to manufacture a product requiring the required precision, and in the mass production process, from the discharge operation for one workpiece to the execution of the discharge operation for the next workpiece. It is necessary to perform processing such as workpiece unloading, loading/positioning of the next workpiece, and alignment processing. During this period, the ink jet head does not have to perform the discharge operation and must stand by, but the liquid material filled in the ink jet head is likely to cause drying due to standby.

[ii] Subject

The third technical idea is characterized in that, after the discharge operation, the liquid material for discharge filled in the flow path in the ink jet head is replaced by a low-volatility liquid material (instead of the material), and the discharge operation is started. Previously, the replacement material was replaced again with the liquid material for discharge. Here, the substitute material preferably belongs to a liquid which dissolves the liquid material or a liquid which has a washing action.

Preferably, after the replacement material is filled in the flow path in the ink jet head, a washing step of cleaning the lower surface of the ink jet head that forms the ejection opening for discharging the liquid material is added.

The ink jet head filled and washed by the above-mentioned substitution material does not have any liquid material remaining, and even in the standby operation of the discharge operation, there is no concern that the liquid material is thickened and solidified from the liquid material. Therefore, the above problems can be completely eliminated.

According to the technical idea, even if the standby time of the discharge operation is long due to an unexpected failure or the like, the precipitation/solidification of the solid component and the nozzle clogging do not occur. Further, since the liquid material is filled in the ink jet head before the discharge operation is being performed, a completely new liquid material can be used for the workpiece.

[iii] Implementation order

The coating operation was carried out in the following order. First, the head cover unit attached under the ink jet head is detached. The nozzle cover unit is configured to keep the ejection opening formed under the inkjet head clean and prevent unnecessary evaporation of the fluid (substituting material) filled in the flow path in the inkjet nozzle communicating with the ejection orifice. In this case, the attachment is performed while the coating operation is in standby.

After the nozzle cover unit is detached, the discharged liquid material is filled in the ink jet head. The flow path in the ink jet head before filling the liquid material is filled with a fluid material different from the liquid material, which is generally referred to as a substitute material. The substitution material is preferably as described above, and has a function of dissolving the liquid material. In the liquid material filling operation, the suction port is covered by the suction/rinsing unit, and a negative pressure is applied to suck the replacement material in the ink jet head, and the ink is discharged by the suction operation. filling. That is, the maintenance method of the ink jet head is a method of repairing a nozzle of the ink jet head by using a unit member and generating a negative pressure to suck the liquid; wherein: the unit member and the negative pressure generating mechanism are provided a connected waste liquid tank; a low-viscosity liquid storage portion connected to the ink jet head; an ink storage portion connected to the ink jet head; and an ink jet head selectively connected to the low-viscosity liquid storage portion or the ink storage portion a liquid switching mechanism; the low-viscosity liquid storage portion is connected to the inkjet head, and the unit member generates a negative pressure, and the ink-jet nozzle is filled with a low-viscosity liquid, and then the ink storage portion is connected to the ink-jet nozzle. Pass and fill the inkjet nozzle with ink.

After the inkjet head is filled with the liquid material to be ejected, the liquid material is projected at a predetermined position other than the workpiece, and it is confirmed whether or not the liquid material is actually ejected (virtual ejection operation). In particular, when the ink jet head is provided with a plurality of injection ports, it is necessary to confirm whether or not the liquid material is ejected from all the injection ports. In this confirmation operation, when the liquid material is not ejected from all the ejection ports, the liquid material filled in the ink jet head is completely discharged and refilled. according to A method of substituting a substitute material for a liquid material is carried out.

After refilling, the virtual ejection operation is again performed, and it is confirmed whether or not the liquid material is ejected from all the ejection orifices. When it is confirmed that the liquid material has been ejected from all the ejection ports, the ink jet head is moved relative to the stage on which the workpiece is placed, and the ink jet head is placed at the application position on the workpiece, and the coating operation is performed.

When the predetermined coating operation is completed, the workpiece is discharged into the workpiece storage device of the general unloader. During the execution of the discharge of the workpiece, the liquid material filled in the flow path in the inkjet is discharged in accordance with the above-described method for the inkjet head, and an operation of filling the replacement material is performed. With this operation, the liquid material in the flow path of the ink jet head is replaced with a substitute material. When the substitute material has a solution for dissolving the liquid material, even if only a slight residual liquid material is present in the flow path, since the filled substitute material is dissolved, liquid solidification does not occur in the flow path of the ink jet head. .

The filling of the replacement material also quietly dissolves and washes the flow path in the ink jet head. After the filling operation of the material to be replaced is completed, the ink jet head is cleaned underneath. The cleaning is preferably carried out by the method using the cleaning liquid described in the above first technical idea. If the nozzle cleaning is completed, the inkjet nozzle is cleaned both inside and outside, resulting in a clean state without liquid material adhering.

After the cleaning has been completed, the nozzle cover unit is attached under the nozzle unit to prevent the evaporation of the replacement material. Repeat the above steps for each workpiece.

(4) Film formation method

[i]Question

Conventionally, the film formation method using inkjet has the following two problems. One is the problem of the height direction (film thickness), and the other is the problem of the horizontal direction. The former cannot solve the coffee stain phenomenon that occurs around the end of the film-forming surface, which makes it impossible to Film formation is a problem of uniform film thickness. The latter is a phenomenon in which the end portion (edge) of the film formation surface is bleed, resulting in a problem that a sharp edge line cannot be formed.

Patent Document 4 discloses that in order to solve the problem that the alignment film thickness is unevenly formed due to the connection between the droplets, the substrate is inclined at a predetermined angle, but the film thickness unevenness has not been completely solved. problem.

In addition, the phenomenon of coffee staining occurs in a low-viscosity solution, which is a fatal problem of the alignment film of the liquid crystal display element. In the case of an alignment film, since the main component of the polyimine is less soluble, a large amount of the dissolved material of γ-butyrolactone, N-methylpyrrolidone or butyl cyanidin is used, and is low. Viscosity is applied by spray coating, which will easily cause coffee stains.

[ii] Subject

The inventors have found that if the coating is applied in such a manner that no liquid flow occurs, the film formation as a whole uniform film thickness can be performed, and the combination of the plurality of liquid droplets which are discharged from the ink jet head and dropped on the surface of the workpiece can be found. The edge line will be leaky, and the fourth technical idea will be created.

The fourth technical idea is characterized in that after the first injection operation of the inkjet head is incident on the workpiece, when the contact position or the overlapping position of the liquid droplets that have fallen through the ejection is emitted, it waits until the workpiece The upper droplets are in a dry state of no flow (including the semi-dry state in which the substance stops moving), and then the ejection is performed.

When the first droplet that has been ejected onto the workpiece by the first ejection operation is dried, the second ejection is also emitted toward the contact position or the overlapping position of the first droplet in the subsequent step of the second ejection operation. The droplets after the action still do not have a fluid binding on the workpiece. In other words, since the liquid droplets (first droplets) emitted by the first injection operation are in a dry state, droplets (second liquids) are not generated after the second injection operation. The contact of the droplets, and the so-called droplet bonding occurs to form a fluid binding situation of a droplet phenomenon.

On the other hand, when it is conventionally known that the first droplet and the second droplet are fluidly combined, since the coffee stain phenomenon is more pronounced, the edge portion of the film is lower than the film thickness at the center. The film thickness is thickened. That is, the difference in thickness between the film thickness at the center of the droplet and the film thickness at the edge formed by the combination of the droplets is compared with the thickness difference between the film thickness at the center of the droplet before bonding and the film thickness at the edge. Become bigger. However, when the droplets are combined to form a single droplet, since the liquid material is highly uniformized due to the flow of the liquid material, it is impossible to examine the contact region or the overlapping region after bonding.

In view of this, in the technical idea, since the film is dried and formed at each ejection operation, the overall thickness difference of the face can be reduced in comparison with the conventional method of generating fluid combination.

Figure 12 is a comparison of the conventional injection method and the method of the present invention in the formation of a film. In Fig. 12, the liquid material which is ejected toward the workpiece as shown in the above figure (a) is the same conventional method, and the first droplet is ejected from the first shot on the workpiece as shown in the following figure (b). An example of a specific film formation method in which each droplet of a group is disposed apart from another adjacent droplet, and then ejected in a manner of burying each droplet gap. In the following figure (b), the second emission that is emitted toward the right side with respect to the emission position of the first droplet group, and the third emission that is emitted toward the lower side with respect to the emission position of the first droplet group are performed, and the first droplet group is emitted. The fourth position of the injection position that is emitted obliquely to the lower right side is emitted. Here, in the second emission, the third emission, and the fourth emission, it is a matter of course that the state in which the flow of the droplets formed by the previous step is suppressed is suppressed, and then the next step is performed. The step of shooting.

In addition, the technical idea is of course not limited to the order of the injection position illustrated in FIG. As long as the multiple injection steps (spraying steps) are used, the entire surface of the workpiece is applied. Evenly coated with a regular injection position. Therefore, the number of injection steps can be less than 3 times, or more than 5 times. If the number of injection steps is increased and the amount of coating per single ejection step is reduced, the unevenness of the surface of the workpiece can be reduced. The reason is that the unevenness of the surface of the workpiece and the amount of coating will have an associated relationship. Further, if the coating amount is reduced, the drying time is also shortened.

Further, when the ink jet unit has a plurality of ejection openings, the plurality of droplets (first droplet group) emitted by the first ejection operation are dropped on the workpiece at a position where the droplets are separated from each other. Not in contact. In this case, the plurality of droplets (second droplet group) emitted by the second ejection operation are not performed until the first droplet group is dried, and the same effect can be obtained.

The droplet drying on the workpiece can be naturally dried, but can be dried more quickly by increasing the temperature of the stage on which the workpiece is placed.

The temperature at which the droplets are dried is appropriately adjusted according to conditions such as the type of the liquid material, the pitch, and the amount of the liquid to be ejected, for example, the experimental ambient temperature (for example, 15 to 25 ° C) plus 150 ° C, preferably the experimental ambient temperature plus 100. Within the range of °C, it is preferred to be in the range of the experimental ambient temperature plus 50 °C.

Further, the drying time for drying the droplets so as not to flow is appropriately adjusted in accordance with conditions such as the platform temperature, the type of liquid material, the pitch, and the amount of injection. For example, it is preferably set to 20 to 100 from the dropping. About seconds.

As described above, the film forming method of the present invention can be applied to various applications such as formation of an alignment film such as a liquid crystal display element because the amount of bleeding of the edge portion can be reduced as compared with the conventional film forming method. The film forming method of the present invention is also applicable to forming a fine wiring pattern on a substrate as shown in FIG. That is, the conventional film forming method may cause a connection between wirings because of a large amount of bleeding, and thus a fine pattern cannot be formed at a high density, but According to the film forming method of the present invention, fine wiring can be formed at a high density. The reason is that the film formation method of the present invention can greatly reduce the amount of diffusion in the lateral direction (horizontal direction) (in the third embodiment to be described later, the amount of diffusion is about 1/10 of the conventional film formation method). The film forming method of the present invention is particularly suitable for film formation having a film thickness of several nm to several tens of μm.

Further, the film forming method of the present invention can also easily control the film thickness. In the conventional film forming method, the liquid material after the dropping is combined with the liquid material which is next ejected to form the same liquid droplet, and diffuses in the lateral direction (horizontal direction), so that it is difficult to control the film thickness. In this regard, the film forming method of the present invention is a liquid material which is in a non-flowing state after falling, and the next liquid material is emitted and accumulated, thereby increasing the film thickness, and thus can be easily controlled by controlling the cumulative number of times. Film thickness.

Hereinafter, the details of the present invention will be described by way of examples, but the present invention is not limited by the examples.

[Example 1]

The cleaning mechanism of the present embodiment includes a cleaning unit that has a function of ejecting the cleaning liquid to the inkjet head 1 and a function of ejecting air.

Fig. 1a shows an overall schematic plan view of a device having the cleaning mechanism of the present embodiment, and Fig. 1b shows an overall schematic side view of the device.

The apparatus of the present embodiment performs a coated inkjet coating apparatus in the case where the inkjet head 10 is moved relative to the workpiece stage 14 located below it.

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 workpiece platform 14 is a vacuum suction type workpiece platform. A temperature control manipulator can also be attached to the workpiece platform 14.

Relative movement of the inkjet head 10 to the workpiece platform 14, and the inkjet head 10 The motion control such as cleaning can be performed from a personal computer (PC; Personal Computer) 15 on the operation table 16 provided beside the coating device.

Fig. 2 is a schematic explanatory view showing a form of a cleaning mechanism of the embodiment.

In Fig. 2, the reference numeral 42 is compressed air from CDA (Clean Dry Air), the reference numeral 43 is a CDA suction opening and closing ball valve, the component symbol 44 is an exhaust air opening and closing ball valve, and the component symbol 45 is exhaust filtering. (manipulator).

Fig. 3 is a schematic structural view showing another embodiment of the cleaning mechanism of the embodiment.

The cleaning unit 20 is for preventing the cleaning liquid from scattering to the peripheral components when the inkjet head 10 is washed. The cleaning unit 20 has a shape such as an open box shape that covers the nozzle surface of the inkjet head 10 and its periphery from below. The cleaning unit 20 is made of a material such as stainless steel or Teflon (registered trademark), for example, because it is necessary to use a material having chemical resistance such as a cleaning liquid.

In the cleaning liquid, the ink adhering to the nozzle surface of the ink jet head 10 and the periphery thereof is completely washed away, and thus a colorless solvent (a solvent which dissolves the main component of the ink) having a factor for dissolving the ink is used.

Fig. 4a is a plan view showing the structure of the cleaning unit 20, and Fig. 4b is a schematic side sectional view showing the cleaning unit 20.

The cleaning unit 20 is provided with an opening 28 at the center of the cleaning lip 23 which is in contact with the ink jet head 10, and is disposed opposite to the plurality of cleaning liquid supply ports 26 at the edge of the long side. .

Fig. 5(a) is an explanatory view at the time of washing. As shown in the figure, the cleaning unit 20 is in contact with the ink jet head 10, and the cleaning liquid is ejected from the cleaning liquid supply port 25 toward the vicinity of the outer peripheral end of the lower surface of the ink jet head 10, and is taken from the cleaning liquid recovery port 26. The liquid receiving unit 21 recovers and performs cleaning.

Fig. 5(b) is an explanatory view showing a state of drying. As shown in the figure, after the cleaning is completed, the ink jet head 10 and the cleaning unit 20 are slightly separated (for example, 3 mm), and the washing adhered to the ink jet head 10 is performed by the atmosphere flowing in the gaps. The cleaning liquid is blown off, and the ink jet head 10 and the cleaning unit 20 are dried. The washing unit 20 is provided with a bottom suction port 24, and the sucked waste liquid is stored in the waste liquid tank 40.

A flow chart of the washing step and the drying step of the ink jet head 10 of the present embodiment, which is schematically illustrated above, is as shown in FIG.

However, when a negative pressure is generated in the cleaning unit 20, the adhesion between the lower surface of the ink jet head 10 (the head surface) and the cleaning unit 20 tends to be important. Here, when the inclination of the washing head unit 20 to the head surface is large, there is a problem that a gap is generated. Therefore, in the present embodiment, the adhesion and sealing property of the cleaning unit 20 can be surely achieved by the structure in which the nozzle surface can be tilted. That is, by supporting the support member that supports the cleaning unit 20 with the softened elastomer, the degree of freedom in which the nozzle face can be tilted can be maintained, and the sealing property can be maintained.

Further, the cleaning unit 20 is provided with an opening and closing mechanism that abuts or does not abut against the inkjet head 10. The opening and closing mechanism can be generally used as a mobile platform such as a manual type, a ball screw type, or a linear type for lifting, for example, a mobile platform manufacturer has a system manufactured by Junhe Seiki Co., Ltd. and a THK company.

"Nozzle inspection mechanism"

The nozzle inspection mechanism of this embodiment is constructed as shown in Fig. 7 .

First, the inkjet head 10 is moved toward the inspection region where the film for inspection is placed. In the inspection area, the state of each ink jet nozzle which the ink jet head 10 has is inspected.

In the inspection area, a transparent inspection film 72 that moves in such a manner as to cross the inkjet head 10 is provided. The inspection film 72 is a film which is soluble in the main liquid 71. The inspection film 72 is taken up in a roll shape by a feeding roller, and is used for winding. The roll of the roll can be used to inspect the new inspection film 72 frequently.

The droplets from the inkjet head 10 are imaged by the imaging device 74. The imaging device 74 can be constituted by a conventional CCD camera or the like. Fig. 7(a) shows an aspect in which the imaging device is composed of two image recognition cameras (area sensors), and Fig. 7(b) shows a configuration in which the imaging device 74 is constituted by a line sensor. In Fig. 7(b), by using the combined reflection illumination 75 and the penetration illumination 76, the visibility is improved. Regardless of the type of design selected, it is a design matter, and is determined according to factors such as the width of the inspection film 72 and the detection accuracy.

In the inspection film 72, when there is no drop of the official liquid 71 or the drop position deviates from the predetermined position, the nozzle inspection mechanism is regarded as an accident such as nozzle clogging, and an error message is displayed.

Fig. 9 is a simplified conceptual view showing the operation of the ink jet head 10. As shown in FIG. 9, the ink jet head 10 can selectively connect the main liquid (ejected liquid material) to the cleaning liquid by the liquid material switching unit 105.

Three units are arranged on the side of the side of the workpiece platform. In the three units arranged, in FIG. 9, the liquid material in the inkjet head flow path is replaced by a substitute material from the left side to the right side, or a suction for replacing the substitute material with a negative pressure for the liquid material is generated/ The rinsing unit 102, the cleaning unit 20 that performs cleaning on the lower surface of the nozzle, and the head cover unit 103 that seals the lower surface of the nozzle.

Fig. 10 is a front view showing the processing operation of the ink jet head 10 constructed in Fig. 9. The six partial maps shown in Fig. 10 will be described. Further, in the switching unit 105, the solid line is in a connected state, and the broken line is in a blocked state.

[10-1] shows a state in which the head cover unit 103 is attached to the lower surface of the ink jet head 10, and is connected to the cleaning liquid by the switching unit. It is the state when the coating job is in standby.

[10-2] is a view showing a state in which the head cover unit 103 is detached from the inkjet head 10 in order to perform a coating operation. The switching unit 105 is located at a position where the ink jet head 10 is in communication with the cleaning liquid phase.

[10-3] A diagram showing a state in which the ink jet head 10 is placed on the suction/rinsing unit 102.

[10-4] After the inkjet head 10 is placed in the suction/rinsing unit 102, the switching unit 105 is conveniently switched to a position where the liquid material communicates with the inkjet head 10. Then, by applying a negative pressure to the suction/rinsing unit 102, a liquid replacement operation (filling operation) in the inkjet head 10 is performed.

[10-5] A diagram showing a virtual ejection operation performed on the suction/rinsing unit 102 after the liquid material is filled in the flow path of the inkjet head 10. The virtual jetting system does not use an image pickup device or a sensing device to confirm whether or not the liquid material is actually ejected from the ink jet head 10, but is performed before the liquid material in the flow path of the ink jet head 10 is officially ejected. Preparing for mobile work. When performing a confirmation operation for performing nozzle inspection, it is preferable to perform a preliminary flow operation in advance. Of course, by confirming the injection in the work, it is also possible to have a preliminary flow operation.

[10-6] A diagram showing a state in which the coating operation is performed when the inkjet head 10 is moved.

Fig. 11 is an explanatory view showing the processing operation of the ink jet head 10 constructed in Fig. 9; The six partial maps shown in Fig. 11 will be described.

[11-1] A diagram showing a state in which the ink jet head 10 is moved to the suction/rinsing unit 102 after the end of the application to be coated.

[11-2] A diagram showing a state in which the ink jet head 10 is placed on the suction/rinsing unit 102, and the liquid material switching unit 105 is switched to a state in which the ink jet head 10 is in communication with the cleaning liquid phase.

[11-3] A diagram showing a state in which the liquid discharge head 10 is removed from the suction/rinsing unit 102 after the liquid replacement operation in the ink jet head 10 is completed.

[11-4] A diagram in which the inkjet head 10 is placed on the cleaning unit 20 and a washing operation is performed. The liquid material switching unit 105 is held at a position where the ink jet head 10 is in communication with the cleaning liquid phase.

[11-5] shows a pattern in which the ink jet head 10 is moved to the head cover unit 103 after the washing step.

[11-6] shows a view in which the head cover unit 103 is attached under the ink jet head 10. By the attachment of the head cover unit 103, the ejection opening is kept clean, and unnecessary evaporation of the replacement material filled in the flow path in the ink jet head 10 can be prevented.

[Embodiment 2]

Fig. 14 is a structural view showing the maintenance mechanism of the ink jet coating apparatus of the present embodiment.

The inkjet head 10 has a plurality of nozzles 6, and discharges the ink 2 stored in the first groove 12 communicated by the communicating member 9 to perform printing. The maintenance of the inkjet head 10 covers the nozzle 6 by the suction/rinsing unit 102, and generates a negative pressure in the suction/rinsing unit 102, and discharges the sucked ink or the like to the suction/rinsing unit 102 and the communication member. 9 connected waste tank 40. The contact between the suction/rinsing unit 102 and the inkjet head 10 is automatically performed by the opening and closing mechanism 7. The opening and closing mechanism 7 may be such that the inkjet head 10 is relatively moved, or the suction/rinsing unit 102 may be relatively moved. Further, depending on the industrial field, it is also possible to form the opening/closing of the suction/rinsing unit 102 by hand.

In the maintenance mechanism of the present embodiment, the second groove 13 that communicates with the communication member 9 by the inkjet head 10, and the inkjet head 10 and the first groove 12 or the second groove are alternatively switched. 13 connected liquid switching units 105. In the second tank 13, the washing liquid 3 which is the first low-viscosity liquid which flows in at the start of maintenance is stored. Real In the embodiment, the cleaning liquid 3 is a solvent in which the ink 2 is dissolved. Thereby, even if the ink 2 solidifies in the flow path, it can be dissolved.

Further, as shown in Fig. 15, the suction/rinsing unit 102 of the present embodiment is configured to have a degree of freedom in tracking the inclination of the head surface.

The abutting member 61 that abuts against the nozzle surface is made of a rubber having a hardness of 40 to 80 degrees (preferably 50 to 70 degrees) (JIS K6253) of the hardened elastomer, and is attached by means of bonding or screwing. Connected to the frame 62.

The frame 62 is supported by a support member 63 that is fixed by adhesion or screwing and is formed by a softening elastic member such as rubber or spring. The support member 63 can also penetrate the nozzle surface mounting error (three-dimensional tilt) of the ink jet head 1, and can also penetrate a depth of 40 to 80 (preferably 50 to 70 degrees). The support member 63 is fixed to the plate-like mounting member 64. A bottom suction port 24 that can connect at least one of the suction through holes and a joint 66 that is connected to the communication member 9 are disposed on the bottom surface of the frame 62.

According to the suction/rinsing unit 102 of the present embodiment constructed as described above, it is possible to ensure complete adhesion and sealing without being affected by the inclination of the nozzle surface.

The negative pressure generating mechanism of the present embodiment is composed of a signal generating device 8, a pressure supply pump 19, a regulator 38, and an ejector 37, and communicates with the suction/rinsing unit 102 via the waste liquid tank 40. In addition, a silencer that absorbs air sound may be added to the negative pressure generating mechanism.

The signal generating device 8 sets and registers the complex pattern time and the voltage signal waveform, and selects and outputs only one of the plurality of registered patterns. The regulator 38 is capable of supplying pressure in accordance with the signal waveform voltage of the signal generating device 8. The signal generating device 8 can also be constituted by, for example, a pulse generator, a PC or the like.

The injector 37 is capable of generating a negative pressure in cooperation with the pressure supplied from the regulator 38. Tune The throttle 38 and the injector 37 are constructed of commercially available air compressors.

Even if the negative pressure generated by the regulator 38 and the injector 37 is not controlled, the throttle amount of the throttle valve provided on the waste side of the injector 37 is performed while maintaining a certain pressure from the regulator 38. Adjust and perform negative pressure control.

The negative pressure generating mechanism of this embodiment is characterized in that the negative pressure generated in the suction/rinsing unit 102 is gently restored to atmospheric pressure. That is, in the present embodiment, the negative pressure change in the suction/rinsing unit 102 is gently generated by the signal generating means 8 which emits the preset signal waveform, whereby the re-mixing of the air bubbles can be prevented.

The set signal waveform is extracted before the negative pressure in the suction/rinsing unit 102 is gently changed, and may be linear, curved, or a signal waveform that changes in a slight stepwise manner. The curvilinear waveform has a Sin waveform as shown in FIG. As shown in Fig. 16 (a), when the signal waveform output from the signal generating means 8 is set to the Sin waveform, the pressure supplied from the regulator 38 is changed as shown in Fig. 16 (b), and the injector 37 is used. As shown in Fig. 16 (c), the negative pressure can prevent vibration from being applied to the meniscus at the tip end of the nozzle 6 of the ink jet head 10.

The coating control method of this embodiment is implemented in the order shown in the flow chart of the left diagram in FIG. First, the power supply of the liquid material application device is turned on (start), and the liquid material application device performs an initializing operation (initial operation). Then, set the relevant device parameters (data settings) of the products (variety) produced. The device parameters are such as: workpiece size, coating area, injection conditions, and the like. If the settings are completed, the production preparation is completed.

Next, the workpiece is supplied from the workpiece supply device of the generic loader to the platform of the liquid material coating device. After the workpiece placed on the platform is positioned on the platform, the coating position on the workpiece is confirmed, and the relative positional deviation of the liquid coating device from the coating position on the workpiece is corrected (aligned). This calibration is based on the position of the workpiece using CCD It is implemented by an imaging device such as a camera and image processing on the captured image. At this time, in addition to the physical correction for rotating the platform, the program correction of the coordinate position correction is performed on the program related to the robot movement. By performing the processing up to this point, preparation for applying the coating to the workpiece on the apparatus platform correctly at the predetermined coating position is completed. When the above correction process is completed, the coating operation is started.

[Example 3]

The film forming method of the present embodiment is an inkjet coating method in which the film is dried until the droplets of the dropped droplets do not flow, and the next droplet is ejected, and the film is formed by dropping. A liquid polyimide system is used for the liquid material, and a glass substrate is used for the substrate.

The polyimide reaction solution is used to form a semiconductor insulating layer and a liquid crystal panel insulating film. The glass substrate is placed on a platform that can be temperature-adjusted in order to dry the liquid material that does not flow.

[Comparative example]

Using a conventional inkjet coating method, after coating a 25 mm square coated region at a pitch of 30 pl/drop and 70 micrometers, the following conditions occurred.

(A) Transverse (horizontal direction): The periphery is spread by about 0.5 to 1.0 mm with respect to a predetermined coating area.

(B) Longitudinal direction (height direction): the center of the coating region is 80 to 85 nm, and the edge portion is about 1000 nm.

[Example 3]

In the inkjet coating method of the present embodiment, the coating region of 25 mm squares was applied in the same manner at 8 pl/drop, 4 shots, and 70 μm pitch, and the following situation occurred.

(A) Lateral (horizontal direction): Peripheral diffusion with respect to a prescribed coating area 0.05~0.1mm degree.

(B) Longitudinal direction (height direction): the center of the coating region is 80 nm to 100 nm, and the edge portion is at a height of about 80 nm to 100 nm.

As described above, it was confirmed that the film formation method of the present embodiment achieves an advantageous effect as compared with the conventional film formation method shown in the comparative example. More specifically, it has been confirmed that the method of the present embodiment can reduce the unevenness formed on the film, reduce the height difference of the entire surface of the film, and further reduce the amount of bleeding at the edge portion.

(industrial availability)

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) and a precision coating device. It can also be applied to inkjet patterning, for example, a coating device/drawing device/printing device for use in applications such as organic EL display panels, large color panel printing, and industrial marking.

The inkjet recording method is also applicable to a mechanical conversion method such as a piezoelectric type or a bubble generation method such as a resistance thermal spray type.

Furthermore, it can also be used in the lens coloring step of the lens manufacturing industry or in the poster and building materials decoration of the large printing industry.

10‧‧‧Inkjet nozzle

14‧‧‧Workpiece platform

15‧‧‧Personal Computer (PC)

16‧‧‧ operation table

40‧‧‧ Waste tank

101‧‧‧Inkjet nozzle control box

102‧‧‧Absorption/rinsing unit

103‧‧‧ sprinkler cover unit

104‧‧‧Image camera

105‧‧‧Liquid material switching unit

106‧‧‧Inkjet control board

107‧‧‧Liquid tank

108‧‧‧Emergency switch

109‧‧‧floor

110‧‧‧ beams

112‧‧‧Various air compressors

113‧‧‧Instrument box

114‧‧‧Control box

121‧‧‧X-axis moving mechanism

122‧‧‧Y-axis moving mechanism

123‧‧‧Z-axis moving mechanism

124‧‧‧θ axis rotation mechanism

125‧‧‧Hθ axis rotation mechanism

Claims (8)

An inspection method of an ink jet head, wherein a liquid material sprayed from a nozzle provided in an ink jet head is dropped on an inspection member, and an abnormality of the nozzle is inspected based on a droplet pattern of a drop, characterized in that The member for inspection is composed of a material which is dissolved by the dropping of the liquid material, and the reflectance of the drop of the liquid material changes. The method for inspecting an ink jet head according to the first aspect of the invention, wherein the member for inspection is composed of a material into which a liquid material of a drop is to be infiltrated. The method for inspecting an ink jet head according to claim 1 or 2, wherein the member for inspection is a film. An inspection apparatus for an ink jet head, wherein a liquid material sprayed from a nozzle having an ink jet head is dropped on an inspection member, and an abnormality of the nozzle is inspected based on a droplet pattern of a drop, characterized in that a member for inspection; an imaging device or a sensing device for identifying a liquid material falling toward the inspection member; and an image processing device for extracting a drop from the image of the imaging field of view including the drop; The member is composed of a material that dissolves due to the falling of the liquid material and changes the reflectance at the drop of the liquid material. The inspection apparatus for an ink jet head according to the fourth aspect of the invention, further comprising an inspection member winding roller. The inspection apparatus for an ink jet head according to the fourth or fifth aspect of the invention, wherein the inspection member is made of a material into which a liquid material of the drop is to be infiltrated. An inspection device for an ink jet head according to claim 4 or 5, wherein The member film for inspection is described. The inspection apparatus for an ink jet head according to claim 6, wherein the inspection member is a film.