JP4952320B2 - Coating liquid application equipment - Google Patents

Description

  The present invention relates to a coating liquid coating apparatus. In particular, a display panel represented by a plasma display panel (hereinafter, also abbreviated as “PDP”), a liquid crystal color filter (LCM), an optical filter, a printed circuit board, a field where a semiconductor coating liquid is applied. For example, the present invention relates to a coating liquid coating apparatus suitably used for forming a stripe pattern on the surface of an object to be coated such as a glass substrate in a PDP manufacturing process.

  In general, a PDP generates discharge in a discharge space formed between a front plate and a back plate, thereby generating an ultraviolet ray centering on a wavelength of 147 nm from a xenon gas, and this ultraviolet ray excites a phosphor to enable display. It becomes. Full-color display can be supported by causing the drive circuit to emit light by separately emitting discharge cells in which phosphors emitting light of R (red), G (green), and B (blue) are separately applied.

  There are two types of PDPs: a direct current type (DC type) in which electrodes are exposed in a discharge space, and an alternating current type (AC type) in which an electrode is covered with an insulating layer. For AC type, a front glass plate on which display electrodes / dielectric layers / protective layers are formed and a rear glass plate on which address electrodes / dielectric layers / rib layers / phosphor layers are formed are bonded together in a striped or grid shape He—Xe or Ne—Xe mixed gas is enclosed in the discharge space partitioned by the barrier ribs. In each of the phosphor layers of R, G, and B, a phosphor paste mainly composed of powdered phosphor particles is filled in recesses formed by barrier ribs extending in one direction for each color formed on the back plate. It becomes. In order to manufacture a product having such a structure with high productivity and high quality, a technique of coating phosphors in a certain pattern is important.

  Conventionally, screen printing has been used for this type of coating process, but in recent years, a base having a plurality of discharge holes is used, and the base is opposed to the back plate, while relatively moving, A method of filling the recess with the phosphor paste has been studied and proposed (see Patent Document 1).

  In this method, the distance between the back plate and the base discharge hole outlet (hereinafter referred to as a gap) is about several tens of μm to several hundreds of μm. In order to uniformly fill the concave portion of the back plate with the phosphor paste from the plurality of discharge holes, it is necessary to set the gap to be equal to all discharge holes and within an appropriate range. If the gap is narrow, it is difficult for the paste to come out due to the back pressure, and the desired discharge amount cannot be filled in the recess. If it becomes narrower, the paste adheres to the periphery of the discharge hole and cannot be applied. Also, if the gap is wide, the columnar flow of the paste coming out of the ejection holes will fluctuate under the influence of the accompanying flow generated by the relative movement of the base and the back plate, and cannot be applied to the recesses. Therefore, it is necessary to set the gap in an appropriate range uniformly in all the discharge holes.

  However, the back plate tends to increase in size, the base is lengthened accordingly, the table on which the back plate is placed becomes large, and it is difficult to keep the gap between the base and the back plate uniform. This is because the deformation due to the self-weight deflection of the base cannot be ignored, and the flatness of the table also deteriorates due to the deformation due to the self-weight deflection. As a result, there is a problem that the phosphor paste cannot be accurately applied to the large back plate.

  As a method of keeping the gap between the coating liquid supply side and the member to be coated constant, it is not a die having a large number of discharge holes as described above, but for example, a slit die holding means is devised so that the slit die slit and the substrate A method for maintaining a uniform clearance from the surface has been proposed (Patent Document 2). Specifically, a method is disclosed in which a slit die is pressed against a die support member from below, a bolt is inserted from above the die support member, and the slit die is fixed to the die support member.

  However, in the method described in Patent Document 2, first, when the slit die is brought into contact with the die support member from below, if the slit die becomes a long object exceeding 1 m, it is difficult to contact the slit die in a horizontal state. As a result, the bolt is tightened in a state where a gap is opened on the contact surface between the slit die and the die support member, and the degree of the difference is left and right. For this reason, there is a problem that the bolt cannot be inserted or it is fixed with a gap on the contact surface, so that it cannot be supported with high accuracy. In addition, since the degree of this gap changes every time the slit die is replaced, the slit die mounting accuracy is not reproducible. Therefore, the accuracy of the clearance between the slit die and the substrate surface also changes with each replacement. There was a problem. In addition, although the amount of deflection of the slit die can be reduced, when the table is deformed by its own weight, the clearance accuracy between the slit die and the table (between the substrates) is deteriorated, and therefore the technology for reducing the deformation of the table itself. Is required separately.

  Furthermore, Patent Document 3 discloses a technique for making the clearance uniform without increasing the rigidity of the holding portion for holding the slit die. The holding part is L-shaped in a cross-sectional view, and the slit die is held so as to be seated.

However, in this method, first, the slit die is supported in a cantilever manner, and the slit die is likely to fall down in a direction in which it is not supported. In order to prevent this collapse, a rotation mechanism can be provided in the longitudinal axis direction of the slit die, but the apparatus becomes complicated and the apparatus cost increases. In addition, the locking surface of the holding portion can be tilted in anticipation of the tipping in advance, but the length and weight of the slit die change with the change of product type, and the degree of tipping down also changes. Therefore, this prior adjustment of the rotation angle requires adjustment every time the product type is changed, and is troublesome. In addition, since the holding part has a structure that supports the slit die in a cantilevered manner, the rigidity is low, and the holding part and the slit die are moved during the application or in the vertical direction to bring the slit die close to the substrate surface before application. Vibration and application defects such as horizontal steps are likely to occur. In addition, before application, it is common to clean the slit part by pressing it against a cleaning device, for example, a rubber roll with a cloth wound around the slit part. When applied, the holding part is deformed due to lack of rigidity, and the slit die escapes. As a result, surface pressure unevenness occurs in the longitudinal direction of the rubber roll and the slit portion, and clean cleaning cannot be performed, and application defects are likely to occur.
Japanese Patent Laid-Open No. 10-27543 JP 2003-282394 A JP 2001-259500 A

  The present invention has been made in view of the above, and can easily increase the rigidity of the entire holder when the base is mounted, and the base and the base holder can be defined even when the base is repeatedly attached and detached. Providing a coating liquid application device that can be fixed with high accuracy and reproducibility, and the gap between the base and the substrate can be set and maintained uniformly over the entire length of the base, making it easy to apply coating liquid with high quality. To do.

  In order to achieve the above object, a coating apparatus according to the present invention includes a table for fixing a substrate, a base for applying a coating solution to the substrate, a base holder for supporting the base facing the substrate, a table and a base. And a moving means for moving the base in a three-dimensional manner, wherein the base holder is spaced apart at equal intervals in the longitudinal direction of the base from the central position and from the central position toward both ends of the base in the longitudinal direction. In addition, there are support portions that support the base from below at at least two positions, and a fixing means that fixes the base to the holder only at the support portions at the at least two positions of the support portions. .

  Further, when the length of the base in the longitudinal direction of the base is L and the distance from the central position of the base to the at least two positions is LS, it is preferable that L and LS satisfy the following formula.

0.25 ≦ LS / L ≦ 0.50 (1)
In addition, the base holder has two plates arranged such that the longitudinal direction thereof is parallel to the longitudinal direction of the base, the width direction thereof is parallel to the height direction of the base, and facing each other. It is preferable to have a base part and a base holding part having the support part arranged so as to intersect the plate part between the two plate parts.

  Moreover, it is preferable that the said base has a mounting part which contacts the said support part, and the said fixing means is a volt | bolt penetrated through this mounting part and fastened to the said support part.

  Moreover, it is preferable that the contact part with the said mounting part is a circle | round | yen, and a volt | bolt penetrates the center in the support part in the said at least 2 position.

  The present invention provides a support unit for supporting the base from below at a central position and at least two positions spaced apart from the central position toward both ends of the base in the longitudinal direction with respect to the longitudinal direction of the base. Therefore, even a wide base can be easily loaded into the base holder, and the mounting portion of the base can be reliably brought into contact with the support member of the base holder. Therefore, even if the base is replaced, the base and the base holder can be fixed at a fixed position with high accuracy. Thus, the gap between the die and the substrate can be constantly maintained over the entire length of the die, and the coating liquid can be applied with high quality.

  In addition, since the base is supported symmetrically with respect to its longitudinal direction, it is possible to prevent the base from being twisted, and from this, adjustment of the height of the support member to make the gap between the base and the substrate uniform, It works directly on gap adjustment and is easy to adjust.

  In addition, since the base is fixed to the holder by only at least two support parts that are equidistant from the center of the support part, the base is not easily affected by the deformation of the base holder, and the gap between the base and the substrate is limited. It is easy to maintain the entire width uniformly, and it becomes easy to apply the coating liquid with high quality.

  The coating liquid coating apparatus of the present invention includes a table for fixing a substrate, a base for applying the coating liquid to the substrate, a base holder for supporting the base facing the substrate, and a table and the base in a three-dimensional manner. For example, and can be applied particularly preferably to a phosphor coating step in a member for a plasma display panel. That is, it can be suitably used when a phosphor paste containing phosphor powder that emits light in any one of the three colors of red, green, and blue is applied to a substrate for a plasma display panel.

  FIG. 1 shows a schematic perspective view of a coating liquid coating apparatus according to an embodiment of the present invention, and FIG. 2 shows a detailed view of a base holder. 2A is a front view, FIG. 2B is a top view, FIG. 2C is a top view of the base holder when the base 2 is removed, FIG. 2D is a longitudinal sectional view, and FIG. (F) is CC sectional drawing of the support part which has a fixing means.

  As shown in these figures, in the present invention, the base holder 1 is in a central position with respect to the longitudinal direction of the base 2 and at at least two positions spaced from the central position toward both ends in the longitudinal direction of the base 2 at equal intervals. It has a support portion 3 that supports the base 2 from below.

  Here, it is preferable that the position of the support portion 3 that supports the base 2 is generally a position where the deflection of the base 2 is minimized. Therefore, especially for the long base 2, it is generally considered that the distance between the support portions is made as narrow as possible, that is, it is only necessary to provide a large number of support portions along the longitudinal direction of the base 2. is there. What should be noted here is that the variation in the height of each support portion is suppressed to about several μm so that the support portion contacts the base 2 uniformly. When the height of each support part is uneven and there is a support part that does not contact the base 2, the deflection of the base 2 may be increased. Therefore, it is necessary to finish the base holder 1 and the height of each supporting part with high precision. However, in the case of a base having a length exceeding 1 m, the base holder is also long, and the height variation of the supporting part is suppressed to several μm. Processing is very difficult. Therefore, the height of the support portion can be adjusted, but in that case, if the number of support portions is large, the adjustment work becomes extremely complicated, which is not preferable. Therefore, it is preferable that the number of support portions of the base holder is small, and it is conceivable to support at two points.

  On the other hand, the base holder 1 is often supported at both ends due to the structure of the coating machine, and therefore tends to be bent by its own weight and the center of the base holder 1 is lowered. Accordingly, the contact surface of the support portion with the base 2 also tends to be inclined toward the center of the base holder, and when the base 2 is mounted in this state, the contact surface on the side of the base is the base portion of the support portion. 2 is followed. That is, the base 2 is also bent and its center is lowered. Therefore, when it is supported at two points, the base 2 also bends together with the base holder 1, and the gap between the base 2 and the substrate 4 becomes large.

  Therefore, in the present invention, the support portions 3 of the base 2 are provided at the center position of the base holder and at at least two positions that are equally spaced from the central position toward both ends of the base in the longitudinal direction of the base. Thus, if the amount of bending of the base holder 1 is measured in advance and the height of the support portion 3 at the center is raised above that amount of deflection or more, even if the base holder 1 is bent. The base 2 will not bend.

  The center position means a range of ± 10% of the length of the base from the center in the longitudinal direction of the base 2, and one of the plurality of support portions may be substantially in the center. That is, when the base length is 1 m, the same effect can be obtained by providing a support portion within a range of ± 10 cm from the center of the base 2. In addition, the equal interval means that the difference in distance between the plurality of support portions other than the support portion provided at the central position from the support portion provided at the central position is within ± 10% of the base length. The distance from the support portion provided at the central position may be substantially equal.

  And in this invention, the support part 3 supports the nozzle | cap | die 2 from the downward direction. Accordingly, the base 2 can be fixed after being placed once, and even when the long base 2 is held, the mounting accuracy does not vary every time the base is replaced or mounted, and the reproducibility is high. Well, the base 2 can be attached.

  In the present invention, the base 2 is fixed to the base holder 1. For this reason, among the support portions 3 of the base holder 1, the support portions 3 b provided at at least two positions spaced at equal intervals from the central position in the longitudinal direction of the base toward the both ends in the longitudinal direction. It has a fixing means to fix to. The base 2 is preferably fixed to the support portion 3b so that the base 2 is pressed onto the support portion 3b from above. Thus, the base 2 can be fixed in the same state (accuracy) as when the base 2 is placed on the support portion 3. The fixing means includes a clamp and a bolt, but a simple configuration, that is, a bolt that is inexpensive and can be fixed securely is preferable. The bolt is inserted into the support portion through the mounting portion 5 of the base 2 and fastened. Furthermore, it is preferable to match the axis of the bolt with the central axis of the support portion. Thereby, the fastening force of the bolt is uniformly transmitted to the support portion and the placement portion, and the support portion and the placement portion can be reliably brought into contact with each other.

  On the other hand, it is preferable that the base 2 is simply placed on the central support portion 3 a without fixing the base 2. This is because the support part and the mounting part of the base have a slight inclination in terms of processing accuracy and mounting accuracy. When the base is pressed against the support part and fixed, the base follows the slight inclination and deforms. Resulting in. In particular, the change in the height of the center of the base immediately appears in the gap accuracy between the base and the substrate, that is, it is sensitive. Therefore, it is preferable that the central support is not fixed and is simply placed.

  As described above, the base 2 is firmly fixed to the base holder 1 by fixing the base 2 to the base holder 1 only by at least two support portions 3b that are equidistantly spaced from the center of all the support portions. The gap between the base 2 and the substrate 4 is not affected by the deformation of the holder 1 and can be maintained uniformly over the entire width of the base. Further, since the base 2 can be firmly fixed, it is possible to prevent the base 2 from being shaken or displaced during application. Further, by this fixing, the base 2 and the base holder 1 are integrated, and the rigidity of the base holder 1 is further increased, so that it is possible to further prevent vibration during application and to prevent uneven application due to vibration. Therefore, according to the present invention, the coating liquid can be applied with high quality.

  The position of the support portion 3b is such that L and LS are 0.25 ≦ LS / where L is the length in the longitudinal direction of the base 2 and LS is the distance from the central position of the base 2 to the at least two positions. It is preferable to satisfy the relationship of L ≦ 0.50, so that the amount of bending can be reduced over the entire length direction of the base 2 including the amount of bending at the center of the base 2.

  In the present invention, only one set of at least two support portions 3b separated from the center at equal intervals may be provided, but two or more sets may be provided from the viewpoint of further suppressing vibration. In this case, it is preferable that all support portions other than the support portion 3a at the center position are provided so as to satisfy the above relational expression. Even if the base 2 is fixed to the support portion 3b in a position satisfying the above relational expression, the influence on the bending of the base 2 is small. In other words, fixing the base 2 with the support portion 3b here prevents the bending. Therefore, the gap accuracy between the base 2 and the substrate 4 is not greatly affected.

  Next, FIG. 3 shows an embodiment of the support portion 3a at the center of the base. (A) is AA sectional drawing of Fig.2 (a), (b) is DD sectional drawing of the support part 3a. If the support portion 3a and the base mounting portion 5 are both flat, it is difficult for the two planes to be in uniform contact with each other, and therefore somewhere in the plane is touched. This is because if the processing accuracy of the surface of the support part and the mounting part is not good, they will not contact each other uniformly, and if the mounting and assembly precision of the support part and the mounting part are not good, the contact surface may be inclined. The contact area and contact position change. In other words, it is not known at which position the base is supported. Thereby, even if the height of the support portion is adjusted, the adjustment allowance may not be read or the adjustment may become dull. In addition, this problem becomes prominent when there are a plurality of caps per coating apparatus. This is because the mounting accuracy of the mounting portion is different for each base, and the contact position of the support portion and the mounting portion is different for each base. Therefore, as shown in FIG. 3, a protruding portion is provided on one of the support portion 3a and the base mounting portion 5 (or a curved surface), and the two are brought into contact with each other in a dot shape so that the contact area between the support portion and the mounting portion can be as much as possible. It is preferable to make it smaller. Thereby, the contact position of a support part and a mounting part is settled in the desired small range, and the dispersion | variation in a contact position can be suppressed to the minimum. Therefore, even when there are a plurality of bases, the positions where the support part and the mounting part come into contact are almost the same in any base, and it is easy to form a uniform gap.

  Further, FIG. 4 shows another embodiment of the support portion 3a. As described above, even when the support portion 3a and the base mounting portion 5 are in linear contact with each other in the short direction of the base, the same as described above. The effect of can be obtained.

FIGS. 2E and 2F show an embodiment of the support portion 3b for fixing the placement portion. The support portion 3b has a circular contact surface with the placement portion, that is, a linear shape. Yes, it is preferable that the bolt penetrates through the center. From this, the fixing and the contact area can both be reduced, and the base can be supported and fixed with high accuracy.
It is preferable that the support portions 3a and 3b can be finely adjusted in height as shown in FIGS. 2 (e), 2 (f), 3 and 4. For example, it can be adjusted by interposing a thin plate 9 having a thickness of several μm to several tens of μm between the support portion 3 of the base holder and the base holding portion 8. The support unit 3 adjusts the height and inclination with reference to the surface of the table 7 on which the substrate 4 is fixed. In particular, the central support 3a is preferably adjusted by mounting the base 2 on the base holder 1 and measuring the distance between the surface of the table 7 and the surface (base surface) where the discharge holes of the base 2 are opened. .

  In recent years, the size of the substrate tends to increase, and the table on which the substrate is placed becomes larger. However, there is a limit to finishing the flatness of the table with higher accuracy, and even if it can be done, it leads to a great cost increase. In addition, the base is lengthened, and it is difficult to keep the gap between the base and the substrate uniform. However, by including the adjustment structure as described above, the straightness of the die surface can be adjusted in accordance with the tendency of the flatness of the table surface of the coating apparatus. That is, the straightness of the base surface can be adjusted by the height of the support portion 3 a located at the center of the base 2. For example, if the flatness tendency of the table 7 is such that the center is slightly recessed, the center support portion may be lowered accordingly. Thus, the gap between the base 2 and the table 7 can be set uniformly in the longitudinal direction of the base 2.

  Further, the height of the mounting portion 5 of the base 2, that is, as shown in FIG. 2E, the distance between the surface of the mounting portion 5 that contacts the support portions 3 a and 3 b and the base surface where the discharge holes are opened. If H is adjusted in advance for each base, variation can be absorbed even when there are a plurality of bases for one coating apparatus. Therefore, it is preferable that the mounting portion 5 be fastened and fixed to the base with a bolt so that it can be removed. It is possible to make adjustments by preparing several mounting parts having different thicknesses and selecting and mounting them. Moreover, the height of the mounting part 5 is adjusted by interposing a thin plate having a thickness of several μm to several tens of μm between the mounting part 5 and the base body (G portion in FIG. 2 (f)). You can also.

  Furthermore, if the rigidity of the base holder is low compared to the rigidity of the base, the base holder will be deformed and it will not be possible to support the base by the support part, even if the amount of flexure of the base is adjusted by the height of the support part. Cannot adjust. Further, the adjustment becomes dull due to the deformation. Therefore, in the present invention, as shown in FIGS. 2 to 4, the base holder 1 is arranged so that the longitudinal direction is parallel to the longitudinal direction of the base and the width direction is parallel to the height direction of the base. In addition, two plate-like portions 10 arranged so as to face each other, and a base holding portion having a support portion arranged so as to intersect the plate-like portion between the two plate-like portions 8 and the base 2 is preferably loaded between the two plate-like portions. Thereby, the cross-sectional secondary moment of the base holder 1 is increased, the rigidity can be increased, and the deflection of the weight of the base holder 1 can be reduced. As a result, the amount of bending of the base can be accurately adjusted with the height of the support portion.

  Next, the overall configuration of the coating liquid coating apparatus according to the present invention will be described.

  In FIG. 1, the substrate 4 is placed on a table 7 and is sucked and fixed by a suction device (not shown) provided on the table 7. The substrate 4 has a coating area 68. The table 7 is supported by a θ-axis member (not shown) that can rotate around the center. The θ-axis member is mounted on a Y-axis drive unit 11 constituted by linear guides 11a and 11b provided on the X-axis drive unit 12, and the table 7 is mounted on the machine base 13 along the linear guides 11a and 11b. It moves in the Y-axis direction and rotates around the θ-axis member. The X-axis drive unit 12 includes linear guides 12a and 12b provided on the machine base 13, and the table 7 moves in the X-axis direction of the machine base 13 along the linear guides 12a and 12b. These X-axis drive unit 12 and Y-axis drive unit 11 are adjusted to be orthogonal to each other. The X-axis drive unit 12 is a relative moving means for applying the coating liquid to the substrate 4 between the base 2 and the substrate 4, and moves the table 7 in the X-axis direction in the application operation.

  Above the center of the machine base 13, a gate-shaped support base 14 is provided in a shape perpendicular to the X axis so that the table 7 moved by the X axis drive unit 12 passes. On the downstream side (back side in the drawing) of the support base 14, a Z-axis drive unit 15 configured by linear guides 15 a and 15 b is provided. Both ends of the base holder 1 are supported by linear guides 15a and 15b, and move in a direction perpendicular to the surface of the table 7 along the linear guides 15a and 15b. A base 2 for discharging the coating liquid is attached to the base holder 1 with reference to the center of the machine base 13 in the Y-axis direction.

Here, a base used in the apparatus according to the present invention will be described.

FIG. 5 shows a longitudinal sectional view in the Y direction of the base 2 shown in FIG. 1, and FIG. 6 shows a longitudinal sectional view in the X direction of the base 2. The base 2 has a coating liquid reservoir 52 for storing the coating liquid 55, a discharge opening 53 for discharging the coating liquid 55, and a coating liquid supply port 54 for supplying the coating liquid 55 to the coating liquid reservoir 52. The discharge opening 53 is composed of a plurality of discharge holes 56 arranged linearly in the width direction of the base 2. The coating liquid supply port 54 is a hole that is inserted into the coating liquid reservoir 52 and opens at the tip of the pipe 57. Further, a liquid level sensor 58 for detecting the liquid level of the coating liquid in the coating liquid reservoir 52 is attached above the base of the support base 14 in FIG. 1, and the liquid level is measured. It is configured to be able to.
The base is selected in accordance with the size of the application region 68. In the present embodiment, the coating liquid can be applied to all the grooves (concave portions) formed in the application region 68 by a single application operation. The discharge holes are arranged in a substantially straight line with the number and pitch corresponding to the grooves. That is, this embodiment is an apparatus for applying a coating liquid to the back plate of a plasma display, and the base 2 corresponds to a groove to which a coating liquid containing any one of R, G, and B phosphor powder is applied. It has discharge holes at several pitches.
A pipe for supplying a coating liquid is connected to the base 2, and a coating liquid tank 43 is connected to an opposite end portion of the pipe through an open / close valve 41 that controls the supply of the coating liquid. A gas pressure source 44 having a predetermined pressure is connected to the coating liquid tank 43 via a pipe. Further, a pipe for supplying a gas pressure for discharging the coating liquid from the discharge hole is connected to the base 2, and a distal end portion on the opposite side of the pipe is connected to a gas pressure source having a desired pressure via a gas pressure switching valve 42. 44. The switching valve 42 is a three-way valve, and is connected to the coating liquid reservoir 52 and the gas pressure source 44, respectively, and is configured to be opened to the atmosphere by switching.
Supply of the coating liquid to the base 2 is performed by opening the opening / closing valve 41 with the switching valve 42 opened to the atmosphere, and a predetermined amount of coating liquid is supplied in a form that leaves a space above the coating liquid reservoir 52. Subsequently, the discharge of the coating liquid is performed by switching the switching valve 42 to the gas pressure source 44 and supplying the gas pressure to this space.
The application process to the substrate includes a process of supplying the coating liquid to the coating liquid reservoir 52 of the base 2 and a process of applying the coating liquid to the application region, which are repeated alternately, for example. In the step of applying the coating liquid to the application region, a part (predetermined amount) of the coating liquid in the coating liquid reservoir 52 is applied to the surface of the application region in one step. Thereby, since the liquid level in the coating liquid reservoir 52 (distance from the discharge hole to the liquid level) is lowered by a certain height, a predetermined amount of coating liquid is supplied (supplemented) in the next coating liquid supply step, The liquid level is set to a predetermined height (coating liquid amount).
Cameras 21 and 23 are attached to the side surface on the upstream side (front side in the drawing) of the support base 14 as first position sensors for measuring the position of the application region 68 of the substrate 4. A camera 22 is attached as a second position sensor for measuring the position of the reference groove. These cameras can be moved independently in the Y-axis direction of the support base 14 via the fine adjustment mechanisms in the X and Z-axis directions, respectively, through the Y1 transport unit 24, the Y3 transport unit 26, and the Y2 transport unit. 25 is attached. The Y1 to Y3 transport units are configured by linear guides 14a and 14b, and the cameras 21, 22, and 23 are configured to have a constant height from the table surface even when moved in the Y-axis direction. Each camera is connected to a monitor television and configured to display an image of the field of view.

Furthermore, in the present embodiment, a control unit 31 configured by a computer or the like and a movement drive unit 34 configured by a servo motor or the like are provided. The control unit 31 includes a movement control unit 33. The movement control unit 33 controls the operation of the coating apparatus via the movement driving unit 34, and relatively moves the substrate 4 and the base 2 in the X direction. The control unit 31 includes a supply control unit 32 having a touch panel unit for inputting and displaying the application conditions, and controls the supply of the coating liquid to the base 2 and the discharge of the coating liquid from the base.
Next, the substrate on which the coating liquid is applied will be described. FIG. 7 is a diagram illustrating an example of the substrate 4 as viewed from above. The substrate 4 has a coating area 68. In each of the application regions 68, linear ribs 35 extending in the application direction are formed at predetermined intervals over the entire surface, and grooves (concave portions) are formed between the ribs. Although not shown, horizontal ribs that divide the grooves may be formed between the ribs in order to improve performance such as improving the luminance of the substrate as the back plate and reducing power consumption. In the vicinity of the four corners of the coating region 68, alignment marks A1 to A4 indicating the positional relationship with the rib pattern formed on the substrate surface are provided. This alignment mark is created together when the rib pattern of the application area is formed. Thereby, the positional relationship between the rib pattern and the alignment mark is formed with high accuracy. The alignment mark is provided so that the straight line connecting A1 and A3 is parallel to the rib pattern, and the straight line connecting A1 and A2 is orthogonal to the rib pattern. In the present embodiment, the reference groove position (reference recess) is set to the center groove position (recess) of each application region. The alignment mark intervals XA and YA and the distance Ys between the reference groove of each coating liquid application groove and the alignment mark are given to the control unit 31 as substrate information.
Next, the alignment between the substrate and the base will be described. FIG. 8 is a partial top view (a) and a partial front view (b) showing a state in which the above-described substrate is arranged in the above-described apparatus. A camera 27 as a position sensor for detecting the position of the base 2 is attached to the upstream end face of the X-axis drive unit 12 at the center position in the Y-axis direction of the machine base. In addition, on each lower surface (discharge hole surface) of the base 2, a mark M indicating the position of the reference discharge hole to be aligned with the reference groove (reference recess) of the substrate is provided in the vicinity of the center of the discharge holes arranged in a row. It is attached. Therefore, by operating the X axis, the position of the reference hole of the base 2 is measured by the camera 27, and the respective X axis and Y axis coordinates are stored.

In the substrate 4, the two alignment marks A 1 on the downstream side are operated by manipulating the X axis of the table at the positions of the cameras 21 and 23 which are previously positioned based on the substrate information with respect to the center in the Y axis direction of the machine base 13. , A2 is moved, and each position is measured. Further, the position of the reference groove of the substrate in the Y-axis direction is measured by the camera 22. The relative position information of the cameras 21, 22, 23, and 27 is given to the control unit 31 in advance. Based on the position coordinates of the reference ejection holes of the base 2 and the reference groove position coordinates of the application area 68 thus obtained, the Y axis and the θ axis of the table are operated to align the substrate and the base in each application area. I do.
In this way, in the Y-axis direction, by making the reference groove of the application region in the center and the reference hole of the base in the center, the positional deviation error due to the distortion of the substrate 4 and the processing accuracy of the base 2 can be halved. The discharge holes of the base 2 can be aligned so as to face all the groove centers formed in 68.
Next, the application operation will be described. When starting the application, first, the coating liquid is supplied into the coating liquid reservoir of the base 2. As described above, the coating liquid is supplied until the opening / closing valve 41 is opened with the switching valve 42 in FIG. Next, it moves to substrate mounting. This operation can be performed in parallel with the supply of the coating liquid into the base 2, whereby the waiting time for supplying the coating liquid to the base 2 can be reduced.
The table 7 is moved to the upstream end. The Y-axis and θ-axis are at the center zero position, and the substrate 4 to be coated by an external transfer machine is mounted almost at the center of the table surface. Fix it. For example, a multi-axis robot is used as the external transfer machine, and the substrate 4 is held horizontally on the table 7 by the robot arm. The table 7 is provided with a plurality of pins that can be raised and lowered, and the pins are raised to receive the substrate, and the arms are retracted and the pins are lowered to receive the substrate on the table surface.

Next, the operation of applying the coating liquid 55 to the application region 68 is started. First, substrate positioning is performed. The table 7 is moved, and the alignment marks A1 and A2 in the application area 68 are placed in the field of view of the cameras 21 and 23. Next, the amount of displacement of the alignment mark A1 in the X and Y directions is obtained with reference to the center of the field of view of the camera 21. Further, the amount of deviation of the alignment mark A2 in the X and Y directions is obtained from the center of the field of view of the camera 23. The inclination of the substrate and the amount of movement of the alignment mark A1 when the inclination is corrected are obtained from these two X-axis direction deviation amounts and the alignment mark interval YA. According to the calculated result, the tilt of the substrate is corrected by rotating the θ axis of the table, and the X and Y axes are moved to align the alignment mark A1 with the center of the visual field of the camera 21.
At this time, since the reference groove of the coating liquid application groove in the application region 68 is observed in the field of view of the camera 22, the center position of the groove is determined and the Y axis of the table 7 is moved, thereby The Y-axis direction positions of the reference hole and the reference groove center of the coating liquid application groove in the application region 68 are aligned.
When positioning is completed, the operation moves to the coating operation of the coating liquid. Confirm that the coating liquid supply into the coating liquid reservoir of the base 2 has been completed (wait if not completed), and set the X axis of the table 7 at a speed programmed in advance downstream from the positioning position of the coating area 68. Move. When the X-axis coordinate reaches a preset coating liquid discharge position, the coating liquid is discharged from the base 2 and when the X-axis coordinate reaches the discharge stop position, the discharge is stopped. The discharge and stop of the coating liquid are performed by the switching valve 42 shown in FIG. This completes the application of the coating liquid 55 to the application area 68. In addition, it can prevent that the residual coating liquid around a discharge hole adheres to a substrate surface by separating the nozzle | cap | die after application | coating finished from the board | substrate.
When the application is finished, the substrate is discharged. For discharging the substrate 4, the table 7 is moved to the downstream end, the adsorbed substrate 4 is released, the pins are lifted and taken out by the transfer machine. By placing one transfer machine exclusively for upstream substrate carry-in and downstream discharge, the next substrate to be coated can be prepared during substrate discharge, so the time from substrate carry-in to discharge can be shortened. it can. A series of operations ends when the substrate 4 is discharged. In the case of continuously applying to the substrate 4, the above-described coating liquid supply is started.
In addition, although the aspect mentioned above was an aspect which apply | coats a coating liquid to a board | substrate by fixing a nozzle | cap | die and moving a table | surface (board | substrate), it moves a nozzle | cap | die and fixes a coating liquid by fixing a table | surface (board | substrate). The same effect can be obtained even if it is applied to the substrate.

<Example 1>
The straightness of the surface where the discharge holes of the die are open was measured using the die holder and the coating apparatus shown in FIGS.

The base has a length of 990 mm. As shown in FIG. 2 (c), the base has two bases in the longitudinal direction of the base (one for each plate-like part), and the base from the center position. A total of 6 pieces (one at each position of each plate-like portion) were installed at locations separated by 277 mm toward both ends in the longitudinal direction. (LS / L = 0.28)
And in the support part of the location 277mm away toward both ends, in order to fix a support part and a nozzle | cap | die, as shown to FIG.2 (e) (f), the bolt of M8 penetrates the mounting part of a nozzle | cap | die. And fastened to the support.

  As shown in FIGS. 3 (a) and 3 (b), the support portion at the center position of the base was made to come into contact at a point with a pointed tip at the portion contacting the base of the base.

  After mounting the base on the base holder and fixing with a bolt, the straightness of the discharge hole surface where the discharge hole of the base is open was measured. Straightness is measured using the commercially available precision height measuring instrument “Mitutoyo 574 Series Heightmatic HDF-N” to determine the distance from the table surface of the coating machine to the discharge hole surface from one end in the longitudinal direction of the die. The place where 7 mm was entered was taken as the first point, and measurements were made at a total of 17 points at equal intervals (61 mm). Then, when the measurement points (first and 17th points) at both ends were used as the reference (zero), the largest value at the other measurement points was taken as the straightness.

  In addition, the height of the portion of each support portion that comes into contact with the mounting portion of the base is measured and adjusted in advance in a state where the base is not mounted on the base holder, and the variation in the height is 20 μm. A thin plate is provided and adjusted between the support part of the base holder and the base holding part so as to fall within the range.

  As a result, the straightness was 6 μm, and the distance between the base surface and the table surface tended to be widest near the center of the base.

  Also, once the base was lowered from the base holder, the base was mounted on the base holder again in the same manner as described above, and the straightness was measured. As a result, it was found that the vicinity of the center of the base was the widest at 5 μm.

  Furthermore, when another base of the same size as the above base was mounted on the base holder and the straightness was measured in the same manner as described above, the distance between the base surface and the table surface tends to be the narrowest at 3 μm. Became.

  From the above, it can be seen that the base can be fixed with good reproducibility even when the attachment and removal of the base are repeated.

<Comparative Example 1>
The support part in the center of the base is a support part that can fix the base with bolts, and is the same as in Example 1 except that the base is fixed with bolts. The straightness is 14 μm, and the distance between the base surface and the table surface is near the center of the base Became the narrowest trend.

  Also, once the base was lowered from the base holder, the base was mounted on the base holder again in the same manner as described above, and the straightness was measured. As a result, it was found that the vicinity of the center of the base was the narrowest at 16 μm.

  Furthermore, when another base of the same size as the base is mounted on the base holder and the straightness is measured in the same manner as described above, the distance between the base surface and the table surface tends to be the narrowest at 21 μm. Became.

<Example 2>
Four support portions (one at each position of each plate-like portion) were installed at locations 475 mm away from the center position of the base toward each end in the longitudinal direction of the base (LS / L = 0.48). Otherwise, the straightness was 4 μm, and the distance between the base surface and the table surface tended to be the narrowest in the middle of the base and the end of the base.

  Also, once the base is lowered from the base holder, the base is mounted on the base holder again in the same manner as above, and the straightness is measured. As a result, the middle of the base and the end of the base are narrowest at 5 μm. It became a trend.

  Furthermore, when another base of the same size as the above base was mounted on the base holder and the straightness was measured in the same manner as above, it was 3 μm, and the center between the center of the base and the end of the base was the narrowest as above. It became a trend.

<Comparative example 2>
The support part in the center of the base is a support part that can fix the base with bolts, and is the same as in Example 2 except that the base is fixed with bolts. The straightness is 20 μm, and the distance between the base surface and the table surface is near the center of the base Became the narrowest trend.

  Further, once the base was lowered from the base holder, the base was mounted on the base holder again in the same manner as described above, and the straightness was measured. As a result, it was found that the vicinity of the center of the base was the narrowest at 22 μm.

  Furthermore, when another base having the same size as the above base was mounted on the base holder and the straightness was measured in the same manner as described above, the distance between the base surface and the table surface tends to be the narrowest at 19 μm. Became.

<Example 3>
Four support portions (one at each position of each plate-like portion) were installed at locations away from the center position of the base by 220 mm toward each end in the longitudinal direction of the base (LS / L = 0.22). Otherwise, the straightness was 9 μm and the distance between the base surface and the table surface tended to be the narrowest at the end of the base.

  Further, once the base was lowered from the base holder, the base was mounted on the base holder again in the same manner as above, and the straightness was measured. As a result, the end of the base tended to be the narrowest at 8 μm.

  Furthermore, when another base having the same size as the base was mounted on the base holder and the straightness was measured in the same manner as described above, the end of the base tended to be the narrowest at 7 μm.

<Comparative Example 3>
In the same manner as in Example 2, except that the three support portions attached to one plate-like portion were removed and the base was cantilevered as in Patent Document 3, and the base was bolted, the base was supported. The cap face was tilted because it fell in the direction that was not, and the straightness could not be measured.

  The present invention can be applied not only to a plasma display panel coating apparatus but also to a liquid crystal color filter (LCM) coating apparatus, and the scope of application is not limited thereto.

1 is a schematic perspective view of a coating liquid coating apparatus according to an embodiment of the present invention. FIG. 2 is an enlarged view of the base holder shown in FIG. 1. It is an enlarged view of one embodiment of the support part in the base shown in FIG. It is an enlarged view of another embodiment of the support part of the nozzle | cap | die center shown in FIG. It is a Y direction sectional view of a mouthpiece shown in FIG. FIG. 2 is a cross-sectional view of the base shown in FIG. 1 in the X direction. It is a top view of the board | substrate mounted in the apparatus of FIG. It is the elements on larger scale of the apparatus of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base holder 2 Base 3 (a, b) Support part 4 Substrate 5 Placement part 7 Table 8 Base holding part 9 Thin plate 10 Plate-like part 11 Y-axis drive part 11a, 11b Linear guide 12 X-axis drive part 12a, 12b Linear Guide 13 Machine base 14 Support bases 14a and 14b Linear guide 15 Z-axis drive parts 15a and 15b Linear guide 21 Camera 22 Camera 23 Camera 24 Y1 transport part 25 Y2 transport part 26 Y3 transport part 27 Camera 31 Control part 32 Supply control part 33 Movement control unit 34 Movement drive unit 35 Rib 41 Open / close valve 42 Switching valve 43 Coating liquid tank 44 Gas pressure source 52 Coating liquid reservoir 53 Discharge opening 54 Coating liquid supply port 55 Coating liquid 56 Discharge hole 57 Pipe 58 Liquid level sensor 68 Application area

Claims (4)

A table for fixing the substrate, and the base for applying the coating liquid to the substrate, and the cap holder that supports so as to face the die to the substrate, and moving means for relatively moving the said said table mouthpiece three-dimensionally A coating apparatus comprising:
The mouthpiece holder, in the longitudinal direction of the die, the at least two locations positioned spaced at equal intervals from the center position and the center position in the longitudinal ends of the die, the supporting portion supporting the cap from below Have
And a support portion at the location of the at least two locations of the support portion has a fixing means for fixing the ferrule to the holder,
Each of the base holders has two plate-like portions arranged such that the longitudinal direction thereof is parallel to the longitudinal direction of the base, the width direction thereof is parallel to the height direction of the base, and facing each other. And a base holding part having the support part, which is arranged so as to intersect the plate-like part between the two plate-like parts . Application of the coating liquid according to claim 1, wherein L and LS satisfy the following formula, where L is the length in the longitudinal direction of the base and LS is the distance from the central position of the base to the at least two positions. apparatus.
0.25 ≦ LS / L ≦ 0.50 (1) The mouthpiece, the has a mounting portion in contact with the supporting portion, the fixing means, through the the placing portion, and a bolt which is fastened to the support part, in any one of claims 1-2 The coating liquid coating apparatus as described. 4. The coating liquid coating apparatus according to claim 3 , wherein the at least two support portions have a circular contact surface with the placement portion, and a bolt passes through the center thereof. 5.

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