JP2010115568A - Droplet application apparatus and droplet application method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a droplet application apparatus which can suppress generation of streak unevenness. <P>SOLUTION: The droplet application apparatus includes coating heads 5 for discharging droplets from a plurality of discharge holes N to a plurality of coating zones formed on the coating surface Ka of an object to be coated K, a moving mechanism 4 for relatively moving the object to be coated K and the coating heads 5 along the coating surface Ka, a storage portion 7a for storing coating position information set and generated for every coating zone so that a droplet dropping pattern to the coating zone is different from that to the adjacent coating zone, and a means for controlling the coating heads 5 and the moving mechanism 4 based on the coating position information stored in the storage portion 7a so that while the object to be coated K and the coating heads 5 are relatively moved, droplets are sequentially discharged from a plurality of the discharge holes N and landed on a plurality of the coating zones. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a droplet applying apparatus and a droplet applying method for applying droplets by applying droplets to an object to be applied.

  In the case of manufacturing a display device such as a liquid crystal display device or an organic EL (Electro Luminescence) display device or a semiconductor device, for example, when forming a color filter (for example, see Patent Document 1), It is used when a functional thin film such as an alignment film or a resist is formed on a substrate such as a glass substrate or a semiconductor wafer.

  This droplet coating apparatus includes a coating head that ejects (jets) a coating liquid such as ink as droplets from a plurality of ejection holes (nozzles) toward a coating target such as a substrate. The droplet coating apparatus causes a plurality of droplets to land sequentially on the coating surface of the coating object with the coating head while relatively moving the coating head and the coating object, thereby forming a predetermined coating pattern.

  When manufacturing a color filter using such a droplet applying apparatus, droplets are applied to a substrate for manufacturing a color filter. That is, red, green, and blue colored inks are applied as droplets to the surface of the substrate for manufacturing the color filter and applied to the recesses separated by the grid-like partition walls (black matrix), and the colored layers are formed in the recesses. (Coating film) is formed. The recess has a rectangular shape in plan view, and this recess corresponds to one pixel (sub-pixel) in the liquid crystal display panel.

Normally, the droplet dropping position is set at the center of the bottom surface of the recess in all pixels, and the droplet is applied to the set dropping position. When the amount of one droplet ejected from one ejection hole is small with respect to the volume of the recess, when forming a colored layer in the recess, a plurality of drops of colored ink are applied to one recess. At this time, since it is necessary to form the colored layer with a uniform thickness, the dropping positions are set at equal intervals along the longitudinal direction of the recess.
Japanese Patent Laid-Open No. 9-230129

  However, as described above, since the dropping position is set to be the same in all pixels, the cross-sectional shapes in the thickness direction of the colored layers in the respective recesses are almost the same. At this time, there is no problem if the droplets land on the set drop position accurately, but the droplets discharged from some of the discharge holes are set due to unexpected problems such as the inclination of the droplet discharge direction. May land out of position.

  In this case, the cross-sectional shape in the thickness direction of the colored layer formed by the droplet discharged from the defective discharge hole is the thickness of the colored layer formed by the droplet discharged from the other discharge hole. It will be different from the sectional shape of the direction. For this reason, since colored layers having a different cross-sectional shape in the thickness direction from other colored layers are arranged in a line, stripes are generated.

  The present invention has been made in view of the above, and an object thereof is to provide a droplet coating apparatus and a droplet coating method capable of suppressing the occurrence of uneven stripes.

  According to a first aspect of the present invention, there is provided a coating head for ejecting droplets from a plurality of ejection holes toward a plurality of coating sections formed on a coating surface of a coating target in a droplet coating apparatus. And a moving mechanism that relatively moves the application object and the application head along the application surface, and an application generated by setting each application section so that the droplet dropping pattern with respect to the application section is different from the adjacent application section Based on the storage unit that stores the position information and the application position information stored in the storage unit, the liquid droplets are sequentially discharged from the plurality of discharge holes while the application target and the application head are moved relative to each other. And a means for controlling the coating head and the moving mechanism to land on the compartment.

  A second feature according to the embodiment of the present invention is that a coating head that discharges droplets from a plurality of ejection holes toward a plurality of coating sections formed on a coating surface of a coating target, a coating target, A droplet coating method for applying droplets to a plurality of coating sections using a moving mechanism that moves the coating head relative to the coating surface, wherein the droplet dropping pattern is adjacent to the coating section. And a step of storing the application position information set and generated for each application section differently, and based on the stored application position information, each of the application objects and the application head is moved relative to each other from the plurality of ejection holes. And a step of ejecting droplets sequentially and landing on a plurality of coating sections.

  According to the present invention, it is possible to suppress the occurrence of uneven stripes, thereby improving the application quality of liquid droplets to the application object.

(First embodiment)
A first embodiment of the present invention will be described with reference to FIGS.

  As shown in FIG. 1, in the droplet applying apparatus 1 according to the first embodiment of the present invention, the substrate K as the application target is in a horizontal state (in FIG. 1, the X axis direction and the Y axis direction perpendicular thereto) The table 2 placed in the X-axis movement mechanism 3 that holds the table 2 and moves it in the X-axis direction, and moves the table 2 in the Y-axis direction via the X-axis movement mechanism 3. The Y-axis moving mechanism 4 to be moved, a plurality of coating heads 5 that eject a coating liquid such as ink as droplets toward the coating surface Ka of the substrate K on the table 2, and the coating heads 5 are each rotated in a horizontal plane. A plurality of rotating mechanisms 6 and a control unit 7 for controlling each unit are provided.

  The table 2 is stacked on the X-axis moving mechanism 3 and is provided so as to be movable in the X-axis direction. The table 2 is moved in the X-axis direction by the X-axis moving mechanism 3. Although the substrate K is placed on the table 2 by its own weight, the present invention is not limited to this. For example, in order to hold the substrate K, a holding mechanism such as an electrostatic chuck or an adsorption chuck is provided. Also good.

  The X-axis movement mechanism 3 is a movement mechanism that guides and moves the table 2 in the X-axis direction. The X-axis moving mechanism 3 is electrically connected to the control unit 7 and its driving is controlled by the control unit 7. As the X-axis moving mechanism 3, for example, a linear motor moving mechanism using a linear motor as a driving source or a feed screw moving mechanism using a motor as a driving source is used.

  The Y-axis moving mechanism 4 is a moving mechanism that guides and moves the X-axis moving mechanism 3 in the Y-axis direction. The Y-axis moving mechanism 4 is electrically connected to the control unit 7 and its driving is controlled by the control unit 7. As the Y-axis moving mechanism 4, for example, a linear motor moving mechanism using a linear motor as a driving source or a feed screw moving mechanism using a motor as a driving source is used.

  These X-axis moving mechanism 3 and Y-axis moving mechanism 4 function as a moving mechanism that relatively moves the substrate K placed on the table 2 and the coating head 5 in the direction along the coating surface Ka of the substrate K.

  The coating head 5 is an ink jet head that ejects a coating liquid such as ink from a plurality of ejection holes (nozzles) N as droplets. The coating head 5 includes a plurality of piezoelectric elements corresponding to the respective ejection holes N. The respective ejection holes N are formed on the ejection surface of the coating head 5 in a straight line at a predetermined pitch (interval). For example, the number of discharge holes N is about several tens to several hundreds, the diameter of the discharge holes N is about several μm to several tens μm, and the pitch of the discharge holes N is several tens μm to several hundreds μm. Degree.

  The coating head 5 is electrically connected to the control unit 7, and its driving is controlled by the control unit 7. The coating head 5 ejects the coating liquid as droplets from each ejection hole N in response to application of a driving voltage to each piezoelectric element. The coating liquid is supplied from a tank that stores the coating liquid. This coating solution is a solution, and includes a solute that remains as a residue on the substrate K and a volatile solvent that dissolves (disperses) the solute. For example, when three types of inks of red, green, and blue are used as the coating liquid, there are three tanks for each color, and the respective color solutions are supplied to the corresponding coating heads 5.

  The rotation mechanism 6 supports the coating head 5 so as to be rotatable in the θ direction (rotation direction along the XY plane in FIG. 1) in a plane parallel to the coating surface Ka of the substrate K. The rotation mechanism 6 tilts the coating head 5 by a predetermined tilt angle with respect to the relative movement direction of the substrate K that relatively moves.

  Here, when coating is performed on the substrate K that relatively moves in the Y-axis direction, the coating pitch of the droplets in the X-axis direction can be adjusted by changing the tilt angle of the coating head 5. In addition, the application pitch in the Y-axis direction can be adjusted by changing the droplet discharge frequency (discharge timing).

  The control unit 7 includes a microcomputer (not shown) that centrally controls each unit, a storage unit 7a that stores various programs, various information, and the like. As the storage unit 7a, a memory, a hard disk drive (HDD), or the like is used.

  Various information includes application information regarding application. The application information includes application position information (for example, a predetermined drop pattern such as a dot pattern) regarding the droplet dropping position, application amount information (droplet ejection amount information) regarding the droplet application amount, and the like. For example, the ejection timing, the inclination angle of the coating head 5, the moving speed of the substrate K, etc. are determined according to the application position information, and the drive voltage applied to the piezoelectric element of the application head 5 is determined according to the application amount information. Is done.

  When a color filter is manufactured using the above-described droplet applying apparatus 1, a substrate K for manufacturing a color filter is used as the substrate K. As shown in FIG. 2, a plurality of coating sections G are provided in a matrix on the coating surface Ka of the substrate K for manufacturing color filters. These application sections G are areas corresponding to the respective pixel areas of the color filter.

  Specifically, a black matrix as a grid-like partition is formed on the coating surface Ka of the substrate K for manufacturing color filters. The black matrix is a grid-like black portion that surrounds the red, green, and blue pixels of the color filter. That is, each coating section G is the bottom surface of a plurality of recesses surrounded by a black matrix. The coating section G is rectangular in plan view, and this coating section G corresponds to one pixel (sub-pixel) in the display panel.

  Here, for example, the coating head 5 may form one coating film with a single droplet or may form one coating film with a plurality of droplets. That is, when the amount of one droplet discharged from one discharge hole N is small with respect to the volume of the recess, when forming a colored layer in the recess, a plurality of droplets are applied to one recess. .

  For example, when six droplets are applied to one application section G, as shown in FIGS. 3 to 7, five dropping patterns P1 to P5 related to the droplet dropping position T with respect to the application section G are used. Is used.

  As shown in FIG. 3, the dropping pattern P1 has two dropping positions T at a position where the first dropping position T is 50 μm from the upper side to the lower side of the coating section G and is increased every 10 μm five times from that position. It is a pattern with the dropping position T after the eye. In addition, the dimension of the arrangement direction of the dropping position T in the coating section G is 150 μm. As shown in FIG. 4, the dropping pattern P2 has a first dropping position T at a position of 45 μm from the upper side to the lower side of the coating section G, and two points at positions increased every 12 μm from that position. It is a pattern with the dropping position T after the eye.

  In addition, as shown in FIG. 5, in the dropping pattern P3, the first dropping position T is at a position of 50 μm from the upper side to the lower side of the coating section G, and increases every 15 μm three times from that position. In this pattern, the second and subsequent dropping positions T are located at positions increased every 5 μm. In the dropping pattern P4, as shown in FIG. 6, the first dropping position T is at a position of 60 μm from the upper side to the lower side of the coating section G, and two points are provided at positions that are increased five times every 8 μm from that position. It is a pattern with the dropping position T after the eye. As shown in FIG. 7, in the dropping pattern P5, the first dropping position T is located at a position of 60 μm from the upper side to the lower side of the coating section G, and two points are provided at a position increased every 5 μm from that position. It is a pattern with the dropping position T after the eye.

  Such dripping patterns P1 to P5 are set for each coating section G so as to be different from the adjacent (adjacent) coating sections G on the coating surface Ka of the substrate K, as shown in FIG. Drop patterns P1 to P5 are randomly assigned to each application section G without regularity, and application position information in the XY coordinate system is generated. Thereafter, the application position information is stored in the storage unit 7a. A random number or the like is used for setting the dropping pattern. In FIG. 2, the numbers in the application section G indicate the dropping patterns P <b> 1 to P <b> 5 set for the application section G. For example, when the number in the application section G is 1, the dropping pattern P1 is set in the application section G, and when the number in the application section G is 2, the application section G has Has a dropping pattern P2.

  Here, it is desirable that the dropping patterns P1 to P5 are set so as to be different from the adjacent coating sections G in all the coating sections G, but the present invention is not limited to this. P1 to P5 may be set to the same pattern in adjacent coating sections G. For example, even if the same drop pattern is lined up next to each other up to three, if the person does not visually recognize the stripe pattern, the same drop pattern may be set continuously in the three adjacent coating sections G. That is, in the present embodiment, the difference from the adjacent coating section G is not necessarily limited to the one in which the dropping pattern is different in the adjacent coating section G. The same shall be included. In addition, although five dripping patterns P1-P5 are used, it is not restricted to this, The number is not limited.

  Next, a droplet application operation (droplet application method) performed by the above-described droplet application apparatus 1 will be described. In addition, although the control part 7 of the droplet coating apparatus 1 performs a coating process based on various programs, here, a colored layer is applied as a coating film on the substrate K for manufacturing color filters using the droplet coating apparatus 1. The case of forming will be described.

  The droplet applying apparatus 1 selectively discharges red, green, and blue colored inks to the application sections G divided by the black matrix provided on the application surface Ka of the substrate K. A colored layer of a predetermined color is formed. The red, green, and blue colored layers are formed so that the same color is repeated in the column direction (Y-axis direction) of the coating section G and red, green, and blue are sequentially repeated in the row direction (X-axis direction).

  More specifically, the control unit 7 of the droplet applying apparatus 1 controls the X-axis moving mechanism 3 and the Y-axis moving mechanism 4 based on the application information including the above-described application position information, and first applies the red ink. The head 5 is positioned at a coating start position facing the coating surface Ka of the substrate K, then the Y-axis moving mechanism 4 is controlled to control the coating head 5 while moving the table 2 in the Y-axis direction. 5, the droplets are sequentially ejected from the ejection holes N, and the droplets are landed in a plurality of rows on the coating surface Ka of the substrate K on the table 2 (scanning coating operation). Thereafter, the control unit 7 moves the application start position by a predetermined amount in the X-axis direction and repeats the scanning application operation. This operation is performed a predetermined number of times, and colored layers are formed in all the red coating sections G. A colored layer is formed in the same manner in the other coating sections G for green and blue.

  In such application, droplets are applied to the adjacent application section G by the application head 5 based on different dropping patterns P1 to P5 (see FIG. 2), and a colored layer (application film) is formed. For example, in the coating section G in which the dropping pattern P1 is set, the droplets sequentially discharged from one discharge hole N of the coating head 5 sequentially land on the six dropping positions T shown in FIG. Further, for example, in the coating section G in which the dropping pattern P2 is set, the droplets sequentially discharged from one discharge hole N of the coating head 5 sequentially land on the six dropping positions T shown in FIG.

  At this time, the cross-sectional shape in the thickness direction of the colored layer formed based on the dropping pattern P1 and the cross-sectional shape in the thickness direction of the colored layer formed based on the dropping pattern P2 (hereinafter simply referred to as the cross-sectional shape of the colored layer). It will be different. This is because the thickness of the colored layer is greater than the other portions in the coating section G on the droplet dropping position T.

  Specifically, when each ejected droplet lands on each dropping position T set by the dropping patterns P1 to P5, the droplets gradually spread and become one, and are colored in the coating section G, that is, in the recess. Become a layer. The cross-sectional shape of the colored layer is such that the thickness of each colored layer is thicker than that of other portions in the coating section G on each dropping position T where the liquid droplets have landed. Therefore, when the dropping patterns P1 to P5 are changed, the cross-sectional shape of the formed colored layer is different.

  As described above, since different dropping patterns P1 to P5 are used in the adjacent coating sections G in each row of coating lines, the cross-sectional shapes of the colored layers are different. As a result, it is possible to reliably suppress the occurrence of unevenness due to the fact that the cross-sectional shape of each colored layer of a certain coating line is uniformly different from the cross-sectional shape of each colored layer of an adjacent coating line.

  More specifically, when the dropping pattern for all the coating sections G is set to the same pattern, an inclination caused by a change in the ink with time in the ejection direction of one of the ejection holes N occurs, resulting in landing position deviation. If so, the cross-sectional shape of each colored layer of the coating line formed by the discharge holes N is different from the cross-sectional shape of each colored layer formed by the other discharge holes N. If the cross-sectional shape of each colored layer is different, a difference in density occurs in each colored layer. Therefore, each colored layer of the coating line formed by the discharge holes N where the landing position deviation occurs is formed by the other discharge holes N. It becomes darker or thinner than each colored layer in the coating line.

  On the other hand, if the dropping patterns P1 to P5 are set to be different in the adjacent coating sections G, even if there are ejection holes N in which landing position deviation occurs, the inside of the coating line and between each coating line The cross-sectional shapes of the colored layers in adjacent coating sections G are different from each other. This makes it difficult to visually recognize the difference in density between each colored layer of the coating line formed by the ejection holes N where the landing position deviation occurs and each colored layer of the coating line formed by the other ejection holes N. Therefore, the occurrence of streak is suppressed. Thereby, the quality of the display panel having a color filter can be improved. Further, even between the application lines of the same color in each row, since the different drop patterns P1 to P5 are used in the adjacent application section G, it is possible to reliably suppress the occurrence of uneven stripes due to the same color application line.

  As described above, according to the first embodiment of the present invention, the dropping patterns P1 to P5 related to the droplet dropping position T with respect to the coating section G are different for each coating section G so as to be different from the adjacent coating section G. By causing the application head 5 to eject each droplet based on the application position information that is set information, the dropping pattern is different in the adjacent application section G, and the cross-sectional shape of the formed colored layer is different. Therefore, it is possible to suppress the occurrence of unevenness due to the fact that the cross-sectional shape of each colored layer of a certain coating line is uniformly different from the cross-sectional shape of each colored layer of an adjacent coating line. As a result, the quality of the display panel having a color filter can be improved. In particular, since the application position information is information generated by randomly assigning a plurality of different dropping patterns P1 to P5 to each application section G, the occurrence of uneven stripes can be reliably suppressed.

(Second Embodiment)
A second embodiment of the present invention will be described with reference to FIG.

  The second embodiment of the present invention is a modification of the first embodiment. Therefore, in particular, portions different from the first embodiment will be described. In the second embodiment, description of the same parts as those described in the first embodiment is omitted.

  As shown in FIG. 8, the control unit 7 selects several drop patterns to be used from among a plurality of drop patterns, sets the selected several drop patterns in each application section G, and applies application position information. An information generation unit 7b for generation is provided. The control unit 7 is connected to an input unit 8 such as a button, a key, or a mouse for receiving an input operation from the operator. The input unit 8 is an operation unit that receives an input operation for selecting several drop patterns to be used from among a plurality of drop patterns. A plurality of dropping patterns (including the dropping patterns P1 to P5 shown in FIGS. 3 to 7) are stored in advance in the storage unit 7a.

  The operator performs an input operation on the input unit 8 to select, for example, five drop patterns P1 to P5 shown in FIGS. 3 to 7 from a plurality of drop patterns. As this input operation, for example, an input operation of pressing five buttons out of a plurality of buttons assigned to each drop pattern, or five droplet patterns P1 out of a plurality of droplet patterns displayed on the display device. ~ There is an input operation etc. to click P5.

  Next, the information generation unit 7b selects five drop patterns P1 to P5 to be used from among a plurality of drop patterns in response to an input operation on the input unit 8, and uses the selected five drop patterns to apply position information. Is generated. Specifically, the information generation unit 7b randomly selects each of the application patterns G1 to P5 so that the selected application patterns P1 to P5 are different from each other in adjacent application sections G on the application surface Ka of the substrate K as illustrated in FIG. And application position information is generated. At this time, the position information of the XY coordinate system regarding each application section G is used, and this position information is also stored in the storage unit 7a in advance.

  As described above, according to the second embodiment of the present invention, the same effect as in the first embodiment can be obtained. Furthermore, by selecting several drop patterns to be used from among the plurality of drop patterns stored in the storage unit 7a and generating application position information using the selected several drop patterns, the operator can If several desired drop patterns are determined from the drop patterns, application position information is automatically generated and stored in the storage unit 7a. Thereby, since it becomes possible to perform application | coating, without performing the operation | work which produces | generates application | coating position information with another apparatus, the convenience of an apparatus can be improved.

(Other embodiments)
The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention. For example, some components may be deleted from all the components shown in the above-described embodiment. Furthermore, you may combine the component covering different embodiment suitably.

  In the above-described embodiment, the substrate K is moved with respect to the coating head 5. However, the present invention is not limited to this, and the coating head 5 may be moved with respect to the substrate K. The coating head 5 and the substrate K may be moved relative to each other.

  In the above-described embodiment, the droplet applying apparatus 1 is used for manufacturing color filters. However, the present invention is not limited to this, and the droplet applying apparatus 1 may be used for purposes other than manufacturing color filters. Good.

  In the above-described embodiment, the application section G is rectangular, but is not limited to this, and may be, for example, a polygon other than a rectangle or an ellipse. Moreover, in the above-mentioned embodiment, although various numerical values are mentioned, those numerical values are illustrations and are not limited.

It is a schematic diagram which shows schematic structure of the droplet coating apparatus which concerns on the 1st Embodiment of this invention. It is explanatory drawing for demonstrating the application position information which the droplet application apparatus shown in FIG. 1 uses. It is explanatory drawing for demonstrating a 1st dripping pattern. It is explanatory drawing for demonstrating a 2nd dripping pattern. It is explanatory drawing for demonstrating a 3rd dripping pattern. It is explanatory drawing for demonstrating a 4th dripping pattern. It is explanatory drawing for demonstrating a 5th dripping pattern. It is a schematic diagram which shows schematic structure of the droplet coating device which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

1 Droplet coating device 3 Movement mechanism (X-axis movement mechanism)
4 Movement mechanism (Y-axis movement mechanism)
5 coating head 7a storage unit 8 input unit G coating section K coating object (substrate)
Ka coating surface N Discharge hole P1 to P5 Drop pattern T Drop position

Claims (6)

An application head for discharging droplets from a plurality of discharge holes toward a plurality of application sections formed on the application surface of the application object;
A moving mechanism for relatively moving the application object and the application head along the application surface;
A storage unit that stores application position information generated and set for each application section so that a droplet dropping pattern for the application section is different from the adjacent application section;
Based on the application position information stored in the storage unit, the liquid droplets are sequentially discharged from the plurality of discharge holes while the application target and the application head are relatively moved, and are applied to the plurality of application sections. Means for controlling the coating head and the moving mechanism to land,
A droplet applying apparatus comprising:   The droplet application apparatus according to claim 1, wherein the application position information is information generated by randomly assigning a plurality of different drip patterns to the plurality of application sections. The storage unit stores a plurality of different drip patterns,
An input unit that receives an input operation for selecting several of the dropping patterns to be used from a plurality of the dropping patterns;
In response to the input operation on the input unit, several drop patterns are selected from the plurality of drop patterns stored in the storage unit, and the selected several drop patterns are different in the adjacent application sections. Means for assigning to the plurality of application sections and generating the application position information,
The droplet coating apparatus according to claim 1, further comprising: A coating head that discharges droplets from a plurality of ejection holes toward a plurality of coating sections formed on a coating surface of the coating target, and the relative movement of the coating target and the coating head along the coating surface A droplet application method for applying the droplets to the plurality of application sections using a moving mechanism that comprises:
Storing the application position information generated and set for each of the application sections so that the drop pattern of the droplets relative to the application section is different from the adjacent application sections;
Based on the stored application position information, the liquid droplets are sequentially ejected from the plurality of ejection holes while relatively moving the application object and the application head, and landed on the plurality of application sections;
A droplet coating method comprising:   The droplet application method according to claim 4, wherein the application position information is information generated by randomly assigning a plurality of different drip patterns to the plurality of application sections. Storing a plurality of different drip patterns;
Select several drop patterns from the plurality of stored drop patterns, assign the selected several drop patterns to the plurality of application sections so as to be different in the adjacent application sections, and generate the application position information And a process of
The droplet coating method according to claim 4 or 5, wherein:

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