JP4127096B2 - Coating head, coating liquid coating apparatus and coating method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is applied to a field such as a display panel represented by a plasma display panel (hereinafter abbreviated as “PDP”), a liquid crystal color filter (LCM), an optical filter, a printed circuit board, and a semiconductor in which a particularly high viscosity coating solution is applied. For example, in a PDP manufacturing process, it relates to a coating liquid coating head, a coating apparatus, and a coating method for forming a thin film pattern while discharging a coating liquid on a surface of an object to be coated such as a glass substrate in a non-contact manner. is there.
[0002]
[Prior art]
In recent years, displays have become increasingly diversified in their methods. One thing that is currently attracting attention is a plasma display that is larger, thinner and lighter than conventional cathode-ray tubes. This causes a discharge in the discharge space formed between the front plate and the back plate, and this discharge generates ultraviolet rays centering on a wavelength of 147 nm from the xenon gas, and the ultraviolet rays excite the phosphor to cause display. It becomes possible. 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), green (G), and blue (B) are separately applied.
[0003]
Of these, the AC plasma display, which has been actively developed recently, has a front glass plate on which display electrodes / dielectric layers / protective layers are formed, and address electrodes / dielectric layers / partition layers / phosphor layers. The discharge glass is bonded to the rear glass plate, and a He—Xe or Ne—Xe mixed gas is sealed in the discharge space partitioned by the stripe-shaped barrier ribs. Each phosphor layer of R, G, and B is formed on a concave portion of a concavo-convex portion formed by a partition wall that extends in one direction for each color formed of a phosphor paste mainly composed of powdered phosphor particles on a back plate. Filled. In order to manufacture such a structure with high productivity and high quality, it is important to have a technique of coating phosphors in a certain pattern.
[0004]
For example, Patent Document 1 discloses a method of coating with a coating head having one or a plurality of ejection holes between the partition walls of a plasma display panel. By the way, the coating head needs to have a structure having a coating liquid reservoir and a space above the coating liquid, injecting pressurized air into the upper space, and pushing the coating liquid from the coating head with the pressure. This is because, in the structure in which the coating liquid is filled in the coating head and the fixed amount liquid is fed by a pump or the like, when the viscosity of the phosphor paste that is the coating liquid is high, the coating start delay caused by the coating liquid piping pressure loss becomes significant. .
[0005]
However, in the coating head having a space above the coating liquid, after the phosphor paste is applied to the substrate that is the object to be coated, the same amount of the phosphor paste as that applied is supplied again into the coating head. There is a need.
[0006]
On the other hand, Patent Document 2 has a structure having a coating liquid dispersion means for dispersing a coating liquid and supplying a coating liquid to the manifold section having a manifold portion and a space above the coating liquid inside. An application head is disclosed.
[0007]
Patent Document 3 discloses a method of supplying a plurality of coating liquid supply ports.
[0008]
[Patent Document 1]
Japanese Laid-Open Patent Publication No. 10-27543 (page 6, 0047, page 12, FIG. 16)
[0009]
[Patent Document 2]
Japanese Patent Laid-Open No. 2001-129464 (second page claim 6, page 10, FIG. 2)
[0010]
[Patent Document 3]
Japanese Patent Laid-Open No. 2001-62368 (page 7, FIG. 1 (b))
[0011]
[Problems to be solved by the invention]
However, the inventors have found that these methods have the following problems. That is, in the invention described in Japanese Patent Laid-Open No. 2001-129464, it is possible to achieve uniform supply in the width direction of the manifold portion. However, in order to increase the supply amount of the coating liquid, the supply hole diameter is increased or the number of holes is increased. A method of increasing When the supply hole diameter is increased, the pressure inside the coating liquid dispersing means (coating liquid supply nozzle) is lowered and becomes a dynamic pressure state, so that the outflow from the supply hole becomes uneven in the width direction. And the liquid level of the coating liquid collected in the manifold portion is high at a location where the amount of outflow from the supply hole is large, and low at a location where the amount of outflow is small. That is, since a difference in height occurs in the liquid level, the discharge amount from the application head (application nozzle) becomes non-uniform in the application head width direction. Similarly, increasing the number of supply holes is also concerned about the effect of dynamic pressure. However, if the hole diameter is reduced as a countermeasure, small diameters and multiple holes will be arranged, which requires a lot of time for cleaning. There is a problem that it ends up.
[0012]
On the other hand, in the method of supplying from a plurality of hole-shaped supply ports as in the method described in Japanese Patent Application Laid-Open No. 2001-62368, it is important to align the supply flow rates from all the supply ports. It is necessary to branch the pipes connected to each supply port into a tournament shape, which increases the number of pipes and joints, which takes time for assembly, and causes problems such as dust generation and an increase in the number of cleaning parts. In addition, in the case of a supply port in which a through hole is opened in a member during cleaning, it takes time to clean, particularly when the hole diameter is small and deep, and it is difficult to check the degree of cleaning. There's a problem.
[0013]
Therefore, an object of the present invention is to solve the above problems. That is, in a coating head that applies a predetermined phosphor paste to a plurality of concave portions of a substrate, in particular, a substrate having a certain uneven pattern formed like a partition wall of a plasma display panel, to a manifold portion inside the coating head High-speed and uniform supply of a large amount of coating liquid, stable and uniform coating operation over a long period of time, and high substrate productivity and high performance by considering the cleaning and assembly properties of the coating head An object is to provide a coating liquid coating head, a coating apparatus, and a coating method method that enable quality.
[0014]
[Means for Solving the Problems]
That is, the present invention includes a discharge manifold portion, On the bottom A discharge opening that opens from the inside to the outside of the discharge manifold; and Provided in a range where the compressed air supply unit provided in the upper part of the discharge manifold unit and the discharge manifold unit are immersed in the coating liquid, An application head having a slit-type application liquid supply port for supplying an application liquid to the discharge manifold section.
[0015]
A slit-shaped coating liquid supply port, characterized in that a supply manifold section for diffusing the coating liquid in the width direction of the coating head is formed upstream of the coating liquid supply port. The top of Supply manifold At the same height as the top surface of the tube or higher than the top surface of the supply manifold section An application head characterized by the above.
[0016]
Also, a table for fixing the substrate, an application head that is provided facing the substrate and applies a predetermined amount of coating liquid to the substrate, a moving means that relatively moves the table and the application head in three dimensions, and application An apparatus for applying a coating liquid to a substrate having a coating liquid tank as a supply source of a coating liquid to a head, wherein the coating head uses the coating head, and a coating apparatus for the coating liquid An apparatus for manufacturing a plasma display panel comprising:
[0017]
Furthermore, the application of the coating liquid to apply the coating liquid to the base material while relatively moving the base material and a coating head in which a plurality of discharge holes provided facing the base material are arranged in a substantially straight line In the method, the coating liquid is supplied to the supply manifold formed inside the coating head to diffuse the coating liquid in the width direction of the coating head, and downstream of the supply manifold. , And provided in a range that can be immersed in the coating liquid of the discharge manifold. From slit-type coating liquid supply port Above Supply the coating liquid to the discharge manifold and collect the coating liquid. , Supplying compressed air to the space above the discharge manifold and discharging the coating liquid from a plurality of discharge ports provided on the lower surface of the coating head. A coating liquid coating method characterized by coating a coating liquid on a substrate, a plasma display panel member manufacturing method characterized by coating using the coating method, and a plasma display member manufactured by the manufacturing method This is a plasma display panel characterized by using.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
First, the coating head of the present invention will be described. FIG. 1 shows an embodiment of the coating head of the present invention. In FIG. 1, the coating head 20 is divided into an upper member 20 a and a lower member 20 b by a dividing surface 19 of a broken line portion, and each is fastened using a bolt 201. The dividing surface 19 of the upper member 20a and the lower member 20b preferably uses a sealing means so that the coating liquid does not leak out. For example, a rubber packing, a metal packing, an O-ring or the like can be used. As another means, the surface roughness of the contact surfaces of the upper member 20a and the lower member 20b is finished to, for example, about 0.4S, the flatness is improved, and a surface seal is used to bring the surfaces into close contact with each other. Also good.
[0019]
In FIG. 1, the coating liquid sent from the coating liquid tank 97 through the coating liquid supply hose 46 is removed by the filter 47 and supplied to the supply manifold section 206 of the coating head 20.
[0020]
Hereinafter, the case where the supply port 206a to the supply manifold portion 206 is one central portion in the width direction will be described. However, the present invention is not limited to this. For example, one supply manifold portion 206 is provided. A plurality of supply ports 206a may be provided.
[0021]
The coating liquid supplied into the supply manifold unit 206 is sufficiently diffused in the width direction in the supply manifold unit 206 and finally fills the supply manifold unit 206. Then, the coating liquid is supplied into the discharge manifold portion 200 from the coating liquid supply port 204.
[0022]
FIG. 2 is a cross-sectional view taken along the line AA of FIG. In FIG. 2, the coating liquid level in the discharge manifold section 200 is managed by a non-contact displacement meter 88. When the liquid level reaches a preset level, the coating liquid control valve 48 is closed and the supply is stopped. To do. The non-contact displacement meter 88 is not particularly limited as long as it can detect the liquid level. However, the non-contact displacement meter 88 may be arranged at the center as shown in FIG. It may be provided (not shown).
[0023]
The discharge openings (discharge holes) 44 are arranged in a straight line in the width direction at the same pitch. When discharging the coating liquid, the discharge holes 44 are caused by the pressure of the compressed air supplied from the compressed air supply hose 81 to the space 202. Then, the coating liquid 42 is discharged and applied.
[0024]
FIG. 3 is a cross-sectional perspective view of the coating head according to the present invention, and the hatched portion in the figure is a broken surface. In FIG. 3, the coating liquid supply port 204 is formed on a surface parallel to the width direction forming the discharge manifold portion 200, and needs to be a slit shape having a long opening in the width direction and a short opening in the height direction. However, the shape is not limited to the slit shape, and may be any shape such as a rectangle, a long hole shape, a sector shape, a hexagon shape, an octagon shape, and the like as long as the shape satisfies the following formula (I).
Opening width direction length / opening height direction length> 1 (I).
[0025]
By making the coating liquid supply port 204 into a slit shape, it is possible to increase the opening area, that is, the cross-sectional area of the flow path through which the coating liquid passes can be increased, and uniform supply in the width direction is possible. . That is, it is possible to uniformly supply more coating liquid in the width direction.
[0026]
Here, the length of the slit in the height direction is preferably 0.1 to 5 mm. If it is less than 0.1 mm, there is a possibility that the opening is closed in the worst case due to processing accuracy or assembly error. Further, if it exceeds 5 mm, it is difficult to widen the coating liquid in the supply manifold portion, and it may be impossible to supply the coating liquid uniformly in the width direction.
[0027]
Further, the supply manifold portion 206 has a cross-sectional shape as shown in FIG. 1, but may be a manifold shape having a curve as shown in FIG. 26 as long as the coating liquid 42 can be diffused in the width direction. Any shape is possible.
[0028]
Here, the coating liquid supply port is preferably formed so that the supply directions thereof are opposed to each other. For example, the coating liquid supply port is preferably formed on both sides with the discharge manifold portion interposed therebetween, and more coating liquid can be applied. This is because it is possible to supply, but depending on the target supply amount, only one side may be provided.
[0029]
4 is a cross-sectional view taken along the line BB of FIG. 1, and FIGS. 5 and 6 are other embodiments of FIG. In FIG. 4, the shape of the supply manifold portion 206 in the width direction is provided so as to have a constant size in the width direction. In this case, the shape is simple, so that the manufacturing cost can be suppressed. In the above-mentioned shape, for the coating liquid of a certain viscosity, the flow rate of the coating liquid is remarkably reduced from the center to the end in the width direction, and there may be cases where sufficient diffusion in the width direction may not be obtained. 5, the shape in the width direction of the supply manifold portion from the center portion to the end portion as shown in FIG. Further, as shown in FIG. 6, for example, the coating liquid supply port 204 may have a slit shape in which the opening height increases from the center to the end in the width direction, depending on characteristics such as the viscosity of the coating liquid to be treated. Any combination of the above may be used.
[0030]
With the shape as described above, the coating liquid can be sufficiently diffused in the width direction by the supply manifold unit 206 and supplied uniformly.
[0031]
Next, the shape of the surface parallel to the coating liquid outflow direction of the coating liquid supply unit will be described. 7 is a cross-sectional view taken along the line CC of FIG. 4, and FIGS. 8, 9, and 10 are other embodiments of FIG. As shown in FIG. 7, the width of the slit-shaped coating liquid supply port 204 is set to be a certain length in the width direction. In this case, the shape is simple, so the manufacturing cost can be reduced. Can do.
[0032]
For coating liquids with a certain viscosity, in the above shape, the flow rate of the coating liquid is significantly reduced from the center to the end in the width direction, and sufficient diffusion in the width direction may not be obtained. 8, it is preferable to make the shape of the slit-shaped coating liquid supply port 204 close to the discharge manifold section 200 from the center to the end in the width direction as shown in FIG.
[0033]
Further, as shown in FIG. 9, the shape of the supply manifold portion 206 can be made to be close to the coating liquid supply port 204 from the center portion to the end portion in the width direction. Further, as shown in FIG. A combination of the above may be used.
[0034]
By adopting the shape as described above, it is possible to uniformly supply in the width direction while taking a large cross-sectional area of the flow path through which the coating liquid passes.
[0035]
11 and 12 show another embodiment of the present invention. FIG. 11 is an example of the BB cross-sectional view of FIG. FIG. 12 is an example of a cross-sectional view taken along line EE in FIG. These are different from FIG. 4 in that three slit-shaped coating liquid supply ports 204 are arranged in the width direction. Thus, any number of slit-shaped coating liquid supply ports 204 may be provided in the width direction. By providing a plurality of slit-shaped coating liquid supply ports 204 in the width direction, a stay 208 for connecting and fixing the upper member 20a and the lower member 20b can be arranged between each, and the connecting bolts 205 are connected and fixed. It becomes possible. That is, for example, when discharging a highly viscous coating liquid from the minute discharge hole 44, since the pressure loss of the discharge hole portion is large, it may not be possible to discharge unless a large pressure is applied to the space portion 202. This is because an extremely large force is applied to the inner surface of the discharge manifold portion 200 and deformation may occur at each part of the coating head 20, but such a phenomenon can be reduced.
[0036]
Even if this deformation is on the order of several μm, depending on the deformation location, the diameter of the discharge holes 44 may be changed, and the pitch in the width direction of the discharge holes 44 may also be changed. In particular, in the case of application of a coating liquid to an uneven substrate (for example, a member for a plasma display panel), the hole diameter of the coating head 20 is very fine from 10 μm to 500 μm, so even if it is a deformation of several μm, The impact is great.
[0037]
If the discharge amount of the coating liquid 42 from each discharge hole 44 changes due to this influence, this directly causes uneven application, resulting in a reduction in quality.
[0038]
Therefore, it is preferable to connect each surface of the slit-shaped coating liquid supply port 204, which is a surface having a large pressure receiving area as in the present invention, by the stay 208. The number of stays 208 is not limited as long as the number of stays 208 is optimum depending on the applied pressure and the strength of the upper member 20a and the lower member 20b. However, in order to reduce the number of stays 208, the upper members 20a and the lower members 20b It is preferable to increase the strength. In the figure, the stay 208 has a shape protruding from the upper member 20a and the lower member 20b. However, the present invention is not limited to this. For example, the upper member 20a is a flat surface and the stay is protruded from the lower member 20b. Or vice versa.
[0039]
Further, it is preferable to use a sealing means on the contact surface between the stay and the other member so that the coating liquid does not leak out like the contact surface between the upper member and the lower member. For example, rubber packing, metal packing, O-ring Etc. can be used. Further, as another means, the surface roughness of the contact surfaces of the upper member 20a and the lower member 20b may be finished to about 0.4S, for example, and the surface flatness may be improved so that the surfaces are in close contact with each other. Good.
[0040]
The shape of the supply manifold portion in the width direction will be described with reference to FIG. The shape of the supply manifold portion 206 in the width direction can be provided so as to have a constant size in the width direction. In this case, since the shape is simple, the manufacturing cost can be suppressed.
[0041]
However, in the above-mentioned shape, the flow rate of the coating liquid is remarkably reduced from the central part to the end part in the width direction for the coating liquid having a certain viscosity, and there is a case where sufficient diffusion in the width direction cannot be obtained. In such a case, it is preferable that the shape in the width direction of the supply manifold portion be close to the coating liquid supply port 204 from the center portion to the end portion in the width direction as shown in FIG.
[0042]
FIG. 14 is a modification of FIG. 11, in which the opening height of the slit-shaped coating liquid supply port 204 a at the center in the width direction is reduced, and the opening height of the slit-shaped coating liquid supply port 204 b at both ends thereof. It is a big one. For a coating liquid having a certain viscosity, the flow rate of the coating liquid is remarkably reduced from the width direction, from the central part to the end part, and sufficient diffusion in the width direction may not be obtained. As described above, by changing the opening height of each slit-shaped coating liquid supply port 204 in the width direction, the coating liquid can be uniformly supplied to the discharge manifold section 200.
[0043]
In this case, the opening height of each of the slit-shaped coating liquid supply ports 204 can be any height as long as the coating liquid 42 can be uniformly supplied to the discharge manifold section 200 and more coating liquid can be supplied. The position in the width direction is not particularly limited regardless of the height of the opening. However, it is preferable to dispose a slit-shaped coating liquid supply port 204a having a minimum opening height in the vicinity of the coating liquid supply port 206a to the supply manifold unit 206.
[0044]
FIG. 15 shows a modification of FIG. 4 and FIG. Two supply manifold portions 206 and slit-shaped coating liquid supply ports 204 are arranged in the width direction. The coating liquid sent through the coating liquid supply hose 46 is divided into two and supplied to the left and right supply manifolds 206. For example, when a base material having a large area is applied and the length in the width direction of the coating head 20 is extremely long, or when it is difficult to diffuse in the width direction due to the properties of the coating liquid, supply as shown in FIG. A plurality of manifold sections 206 and slit-shaped coating liquid supply ports 204 are preferably arranged in the width direction. In this case, one coating liquid control valve 48a, 48b can be provided for each of the coating liquid supply ports 206a to the supply manifold section. FIG. 16 is a modification of FIG. 15 in which the shape of the supply manifold portion is made closer to the coating liquid supply port 204 from the center to the end in the width direction.
[0045]
Next, the shape of the surface parallel to the coating liquid outflow direction of the coating liquid supply unit will be described. FIG. 17 corresponds to a sectional view taken along the line DD of FIG. Further, in this drawing, the positions of the holes of the bolt 201 for fastening the upper member 20a and the lower member 20b are also illustrated. The bolt 201 is disposed at a position where the periphery of the surface with which the coating liquid 42 contacts can be fastened, and the bolt 201 is disposed so that the stay 208 can also be fastened. At this time, it is preferable to consider so that the coating liquid does not leak out. For example, rubber packing, metal packing, O-ring, or the like can be used. Further, as another means, the surface roughness of the contact surfaces of the upper member 20a and the lower member 20b may be finished to about 0.4S, for example, and the surface flatness may be improved so that the surfaces are in close contact with each other. Good.
[0046]
As shown in the figure, the slit-shaped coating liquid supply port 204 has a shape in the width direction so as to have a constant length in the width direction, and two stays 208 are provided. The liquid supply port 204 is divided into three places in the width direction.
[0047]
When the coating liquid sufficiently diffused in the width direction by the supply manifold section 206 passes through the slit-shaped coating liquid supply port 204, the coating liquid 42 is divided into three. Then, it is supplied to the discharge manifold unit 200, and the three divided coating liquids merge.
[0048]
At this time, it is difficult for the coating liquids to completely mix with each other at the merged portion. In this state, when the coating liquid 42 is ejected from the ejection holes 44 and applied to the substrate 4, the result is directly below the merged location. This causes a coating defect. In this state, when the coating liquid 42 is further supplied to the discharge manifold unit 200, this phenomenon becomes more prominent.
[0049]
Accordingly, as shown in FIG. 18, the stay 208 and the slit-shaped coating liquid supply port 204 arranged on both sides and opposed to each other are shifted by a half pitch in the width direction, so that the slit-shaped supply manifold portion 206 is separated from the supply manifold portion 206 on one side. The other slit-shaped coating liquid supply port 204 is disposed so as to be opposed to the place where the coating liquid supplied to the discharge manifold unit 200 passes through the coating liquid supply port 204 and is opposed to the merged place. By supplying the coating liquid from the coating liquid supply port, it is possible to disperse the junctions and make the distribution in the width direction of the coating liquid 42 uniform. Here, the amount of shifting is preferably a half pitch, but may be any amount of shifting as long as the joined portions can be dispersed. As another means, as shown in FIG. 19, coating liquid control valves 48 a and 48 b are provided upstream of the supply manifold section 206, respectively, and the respective supply amounts of the coating liquid to the supply manifold sections 206 on both sides are controlled. In addition, it is preferable to disperse the merging points by changing the flow rate flowing out from the slit-shaped coating liquid supply port so that the portions where the coating liquids merge in the discharge manifold portion are shifted as needed. Alternatively, when the coating liquid control valve 48a is opened and the coating liquid is supplied to the supply manifold section 206 on one side, the coating liquid control valve 48b is closed and the supply of the section to the other supply manifold is stopped. The same effect as described above can also be obtained by switching in an arbitrary cycle. The above may be combined or performed alone.
[0050]
In addition, slits as shown in FIG. 20 are used so that coating liquids having various viscosities and characteristics can be sufficiently diffused in the width direction of the coating head supply manifold section 206 and can be uniformly supplied to the discharge manifold section 200. In this case, the supply manifold portion 206 is more easily diffused in the width direction as compared with FIG. 21, and the slit-type coating liquid supply port 204 supplies more uniformly. It becomes possible. Further, the supply manifold portion 206 as shown in FIG. 21 makes it possible to supply more uniformly than in the case of FIG.
[0051]
20 and 21, the stay 208 is preferably inside the slit length 203. For example, the length of the stay 208 in the coating liquid flow direction is shorter than the slit length 203, and at least downstream of the stay 208 in the coating liquid flow direction. It is preferable to form the stay 208 so as to provide the slit 203a. At this time, a slit 203b may be provided on the upstream side. When there are a plurality of stays 208, it may be carried out for at least one stay. Depending on the characteristics of the coating liquid, the values of the slits 203a and 203b may be changed from the center to the end in the width direction. May be.
[0052]
When the length of the stay 208 in the coating liquid flow direction is equal to or longer than the slit length 203, the stay 208 is shifted to the supply manifold unit 206, and at least downstream of the stay 208 in the coating liquid flow direction. It is also possible to form the stay 208 so as to provide the slit 203a on the side.
[0053]
In this way, when the coating liquid flowing in from the supply manifold section 206 passes through the slit-shaped coating liquid supply port 204 and is supplied to the discharge manifold section 200, it merges in the discharge manifold section 200. Since the merging is completed in the slit-shaped coating liquid supply port 204 before the cleaning, the time required for the coating liquid to be divided by the stay 208 can be shortened. The coating liquid can be uniformly supplied to the discharge manifold unit 200 in the width direction while being minimized.
Further, as described above, a bolt (not shown) may be arranged so that the stay 208 can be fastened. The shape of the stay 208 may be a cylinder, a rhombus, or any shape such as an ellipse or an airfoil.
Further, as shown in FIG. 30, at least one second supply manifold section 207 may be provided between the slit-shaped coating liquid supply port 204 and the discharge manifold section 200. When the outflowing coating liquid remains divided in the stay, the coating liquid is merged in the second supply manifold section 207, made uniform in the width direction, and supplied to the discharge manifold section 200. The coating liquid can also be supplied to the discharge manifold unit 200 from the port 209.
[0054]
Moreover, it is preferable to arrange | position the position of the height direction of the slit-shaped coating liquid supply port 204 in the coating head 20 in the range immersed in a coating liquid, as shown in FIG. More preferably, the coating liquid is arranged below in the coating head 20, so that the coating liquid is less likely to fall while winding around the nozzle even when there is no coating liquid in the discharge manifold unit 200 (initial filling). Therefore, less air is involved in the coating liquid. When air is entrained in the coating liquid, bubbles are formed in the coating liquid, and when the bubbles are ejected from the ejection holes 44, there is a defect of missing coating.
[0055]
Further, if there are a plurality of slit-shaped coating liquid supply ports 204 within a range where the coating liquid supply port 204 is immersed in the coating liquid, the positions in the height direction may be shifted.
[0056]
At this time, if the coating liquid is to be transmitted to the inner surface of the discharge manifold section, the position of the slit-shaped coating liquid supply port 204 in the height direction is higher than the coating liquid surface as shown in FIG. You can also
[0057]
In this case, for example, the coating head 20 may be divided into three parts of an upper member 20a, an intermediate member 20c, and a lower member 20b, and each may be fastened with a bolt 201.
[0058]
Further, it is preferable that the inner surface of the slit-shaped coating liquid supply port 204 can be divided into two members, that is, an upper member 20a and a lower member 20b, between the surfaces facing each other. By doing so, when disassembling and cleaning the coating head 20, the surface in contact with the coating liquid can be directly visually observed, and the cleaning operation is facilitated, so that the cleaning performance is improved, and after cleaning. The confirmation work is also easy.
[0059]
Next, FIG. 28 and FIG. 29 will be described. 28 and 29 show another embodiment of the coating head of the present invention shown in FIG. 1, and shows a case where the coating liquid is supplied to the discharge manifold section 200 from one side.
For example, in general, when air is mixed in the coating liquid, there is a case where the coating omission defect occurs such that the air in the coating liquid is ejected from the ejection hole 44 at the time of ejection, and only a part of the coating is interrupted.
[0060]
Alternatively, when air accumulates in the upper portion of the supply manifold portion 206 due to the characteristics of the coating liquid, etc., when pressure is applied to the space portion 202 during discharge, the volume of the air in the supply manifold portion 206 Is compressed, and the liquid level of the coating liquid in the discharge manifold 200 is drastically lowered. Next, when the pressurization is stopped and the space 202 is returned to the atmospheric pressure, the liquid level rapidly returns to the vicinity of the original height. At this time, when the discharge amount is extremely small and the pressure is rapidly returned to the atmospheric pressure after the pressurization, it may rarely return to a height that exceeds the liquid level before the pressurization. Therefore, particularly when the liquid level is detected by the non-contact displacement meter 88 as shown in FIG. 2, the management of the amount of the coating liquid accumulated in the discharge manifold section 200 becomes unstable.
[0061]
Therefore, when air is mixed in the coating liquid or when air accumulates in the upper portion of the supply manifold portion 206 due to the characteristics of the coating liquid, as shown in FIG. 28, as shown in FIG. It is preferable that at least one surface of 204 is connected to the uppermost portion of the surface forming the supply manifold portion 206. In addition, as shown in FIG. 29, the slit-shaped coating liquid supply port 204 communicates with the uppermost portion of the surface forming the supply manifold portion 206.
If the above is satisfied, the slit-shaped coating liquid supply port 204 may be in any position and direction with respect to the uppermost portion of the surface on which the supply manifold portion 206 is formed. In addition, the uppermost part here means the part located on the uppermost side with respect to the direction of gravity.
Furthermore, the position in the height direction of the portion where the slit-shaped coating liquid supply port 204 communicates with the discharge manifold portion 200 is the same as or higher than the uppermost portion of the surface forming the supply manifold portion 206. Is more preferable.
[0062]
Since the air in the coating liquid or in the supply manifold unit 206 tends to accumulate upward, all the air flows out to the discharge manifold unit 200 side as shown in FIGS. In the discharge manifold portion 200, air escapes from the coating liquid and floats to the space portion 202 that is open to the upper atmosphere, so that this air does not cause a problem during discharge. Therefore, since there is no large air reservoir in the coating liquid supply port 204 from the supply manifold unit 206, the liquid level does not change drastically at the time of discharge. Therefore, the liquid level can be detected and managed accurately. It becomes possible.
The above is not limited to this. For example, in FIG. 28, the slit-shaped coating liquid supply port 204 may communicate with the discharge manifold unit 200 obliquely upward (not shown). Further, the present invention can also be applied when the second manifold portion 207 is provided as shown in FIG.
[0063]
The contents described above may be used in any combination.
The coating liquid coating apparatus and coating method of the present invention can be particularly preferably applied to the phosphor coating step in the plasma display panel member.
[0064]
Next, the overall configuration of the coating liquid coating apparatus according to the present invention, particularly an example of the overall configuration of the coating liquid coating apparatus on an uneven substrate (for example, a member for a plasma display panel) will be described.
[0065]
FIG. 22 shows an example of a coating apparatus applied to manufacture of the plasma display panel according to the present invention. This apparatus includes a base 2. A pair of guide groove rails 8 is provided on the base 2, and the table 6 is disposed on the guide groove rails 8. The upper surface of the table 6 is provided with a plurality of suction holes 7 so that the base material 4 having unevenness formed on the surface in a striped pattern at a certain pitch can be fixed to the table surface by vacuum suction. ing. The substrate 4 is moved up and down on the table 6 by lift pins (not shown). Furthermore, the table 6 can reciprocate in the X-axis direction on the guide groove rail 8 via the slide legs 9.
[0066]
A feed screw 10 constituting the feed screw mechanism shown in FIG. 1 extends between the pair of guide groove rails 8 through a nut-like connector 11 fixed to the lower surface of the table 6. Both ends of the feed screw 10 are rotatably supported by the bearing 12, and an AC servo motor 16 is connected to one end of the feed screw 10.
[0067]
As shown in FIG. 22, above the table 6, a coating head 20 that discharges the coating liquid is connected to an elevating mechanism 30 and a width direction moving mechanism 36 via a holder 22. The elevating mechanism 30 includes an elevating bracket 28 that can be moved up and down, and is attached to a pair of guide rods inside the casing of the elevating mechanism 30 so as to be movable up and down. In the casing, a feed screw (not shown) made of a ball screw located between the guide rods is also rotatably arranged, and is connected to the lifting bracket 28 via a nut-type connector. . An AC servo motor (not shown) is connected to the upper end of the feed screw, and the lifting bracket 28 can be arbitrarily moved up and down by the rotation of the AC servo motor.
[0068]
Further, the elevating mechanism 30 is connected to the width direction moving mechanism 36 via a Y-axis moving bracket 32 (actuator). The width direction moving mechanism 36 moves the Y axis moving bracket 32 so as to reciprocate in the width direction of the coating head, that is, the Y axis direction. Guide rods, feed screws, nut type connectors, AC servo motors and the like necessary for operation are arranged in the casing in the same manner as the lifting mechanism 30. The width direction moving mechanism 36 is fixed on the base 2 by a column 34.
[0069]
With these configurations, the coating head 20 can be freely moved in the Z-axis and Y-axis directions.
[0070]
Further, an inverted L-shaped sensor column 38 is fixed to the upper surface of the base 2, and a height sensor 40 that measures the position (height) of the top of the convex portion of the base material 4 on the table 6 at the tip thereof. Is attached. Next to the height sensor 40, a camera 72 that detects the position of the uneven portion of the substrate 4 is attached to the support column 70. As shown in FIG. 1, the camera 72 is electrically connected to the image processing device 74 and can quantitatively determine the change in the uneven portion position.
[0071]
Further, a sensor 66 is attached to one end of the table 6 through a sensor bracket 64 to detect the position of the lower end surface (discharge hole surface) of the coating head 20 with the discharge holes in the direction perpendicular to the table 6.
[0072]
Next, an embodiment of the coating liquid coating apparatus according to the present invention will be described with reference to FIG. 1 for the portion where compressed air and coating liquid are supplied to the coating head 20 and discharged.
The coating head 20 has a discharge manifold section 200 therein, and a space section 202 is provided above the coating liquid surface. The space 202 is connected to a compressed air supply hose 81, a compressed air control valve 82, a pressure reducing valve 84, and a compressed air source 86, and is configured to be able to supply compressed air with an arbitrary pressure. The pneumatic control valve 82 is controlled to be opened and closed by the overall controller 60. FIG. 1 shows a case where a plurality of ejection holes are arranged in a substantially straight line in the coating head 20. The pneumatic control valve 82 is controlled to be open when the coating liquid is applied, and discharges the coating liquid from the discharge hole 44 by the pressure of the compressed air supplied to the space 202 in the coating head 20. The discharge hole 44 preferably has a hole diameter of 10 to 500 μm depending on the application width of the coating liquid. The shape and number of the discharge holes 44 are not particularly limited, and may be any shape depending on the purpose of application. For example, a shape having a long opening in the width direction of the coating head may be used so that the coating liquid is discharged in a sheet form.
[0073]
The width direction of the coating head here is the Y-axis direction in FIG. 22, that is, the longitudinal direction of the coating head.
[0074]
Moreover, the width direction length of the coating head 20 is longer than the coating region of the base material 4, and the coating head 20 is relatively long to complete the coating on the base material 4 by moving once relative to the base material 4. The shape is preferable, but, for example, it may be applied by being moved a plurality of times with a short application head shorter than the application region.
[0075]
Further, a coating liquid supply port 204 for supplying a coating liquid is formed on the side surface of the discharge manifold section 200, and further, the supply manifold section 206 is provided upstream to diffuse the coating liquid in the width direction. Is preferably formed.
[0076]
Here, as described above, the coating head of the present invention is not completely filled with the coating liquid even during normal use, and has a space above the coating liquid. Depending on the conditions and the like, the present invention is not limited to this, and it is also possible to fill completely.
[0077]
The amount of the coating liquid accumulated in the discharge manifold section 200 in the coating head 20 is detected every time the coating operation is stopped. The coating apparatus of the present invention has a detecting means for detecting the coating liquid amount in the coating head in a non-contact manner with respect to the coating liquid. By using a non-contact detection means, contamination of the coating liquid can be prevented. Here, FIG. 23 shows a configuration in which the liquid level of the discharge manifold section 200 is measured using a non-contact displacement meter 88 which is a non-contact detecting means for the coating liquid amount. FIG. 23 shows a case where there is one slit-shaped coating liquid supply port. The non-contact displacement meter 88 is electrically connected to the overall controller 60, and the overall controller 60 controls the supply device controller 58 according to the detection signal. Further, the non-contact displacement meter 88 is not fixed directly to the coating head 20 but is fixed to the sensor bracket 90 which is a separate member, so that the non-contact displacement meter 88 is always a separate member even when the coating head 20 is replaced. It is in a fixed state, and there is no need to adjust the sensor position or the like every time the coating head is replaced.
[0078]
The sensor bracket 90 can be moved and adjusted in the position height direction of the non-contact displacement meter 88 in consideration of the difference in the detected liquid level due to the difference in the shape and specifications of the application head 20, and at any position. What can be fixed is preferred. In the present invention, the non-contact displacement meter 88 can be applied as long as it is a sensor capable of non-contact detection such as a laser type or an ultrasonic type, and the laser type displacement meter is most preferable from the viewpoint of detection accuracy and wide detection range. In this case, a transparent plate 92 is attached to the coating head 20 so that the liquid level can be detected.
[0079]
Next, another embodiment of the non-contact detection means for the coating liquid will be shown. FIG. 24 shows the measurement of the weight of the coating head as the coating head coating amount detection means. The weight detection sensor 96 is preferably installed between the coating head 20 and the holder 22 that supports the coating head, and preferably measures only the weight of the coating liquid within the coating head 20 and the coating head. The installation location is not limited as long as it can be measured. The weight detection sensor 96 is electrically connected to the overall controller 60 in the same manner as the non-contact displacement meter 88, and the overall controller 60 controls the supply device controller 58 according to the detection signal as described above. Most preferably, the weight detection sensor 96 uses a load cell that can convert the detected weight into an electrical signal.
[0080]
A filter 47, a coating liquid supply hose 46, a coating liquid control valve 48, and a coating liquid tank 97 are connected to the supply manifold unit 206 in the coating head 20. The coating liquid 42 is stored in the coating liquid tank 97 and is connected to the pressurized air source 50 via the pressure control valve 54. The pressurized air source 50 is preferably a gas supply device such as air or nitrogen, and is preferably provided with a pressure reducing valve (not shown) to adjust the pressure.
[0081]
In FIGS. 23 and 24, the coating liquid control valve 48 is preferably a non-sliding type in which the valve opening / closing portion is the same as in FIG. As a result, it is possible to prevent wear powder from being mixed into the coating liquid 42, and to prevent defects in light emission defects due to contamination by foreign matters in the manufacture of the plasma display panel. Thus, it is preferable to use a non-sliding type valve for the valve used for the portion through which the coating solution contacts and passes in other pipes.
[0082]
FIG. 25 is a diagram schematically showing the supply / replenishment timing from the coating liquid tank 97 to the coating head 20. The supply of the coating liquid from the coating liquid tank 97 to the coating head 20 is performed when the coating head 20 is not coated on the substrate, that is, the coating on the substrate is once finished and the coating on the next substrate is started. This is done during the previous interval. This interval is mainly used for alignment of the base material 4 and the coating head 20, but considering the tact time, it is preferable to allow the coating liquid supply to the coating head 20 within this interval.
[0083]
Further, the motor controller 62 includes the AC servo motor 16 that drives the table 6, the actuators 76 and 78 (for example, AC servo motors) of the elevating mechanism 30 and the width direction moving mechanism 36, and the moving position of the table 6. A signal from the position sensor 68 to be detected, a signal from each of the Y and Z axis linear sensors (not shown) for detecting the operating position of the coating head 20, and the like are input. Instead of using the position sensor 68, it is also possible to incorporate an encoder in the AC servomotor 16 and detect the position of the table 6 based on a pulse signal output from the encoder. In the overall configuration of the coating liquid coating apparatus described above, the height sensor is a non-contact measurement type using a laser, ultrasonic wave, etc., or a contact measurement type using a dial gauge, a differential transformer, etc. Any material having a measurable principle may be used.
[0084]
Further, the detection means for detecting the relative position where the discharge hole 44 of the coating head 20 corresponds to the concave portion may be configured by an image processing apparatus using a camera that individually detects the concave portion and the discharge hole of the substrate.
[0085]
Next, the basic operation of the coating method using this coating apparatus will be described with reference to FIG. First, when the origin of each operation unit in the coating apparatus is returned, the table 6 and the coating head 20 move to the X-axis, Y-axis, and Z-axis preparation positions, respectively. At this time, the coating liquid is already filled from the coating liquid tank 97 to the coating head 20. A lift pin (not shown) rises on the surface of the table 6, and a base material 4 in which partition walls are formed in a stripe pattern with a constant pitch from a loader (not shown) is placed on the lift pin.
[0086]
Next, the lift pins are lowered to place the base material 4 on the upper surface of the table 6, and after the positioning on the table 6 is performed by an alignment device (not shown), the base material 2 is sucked.
[0087]
Next, the table 6 moves until the partition wall (the top of the convex portion) of the base material 4 comes directly under the camera 72 and the height sensor 40 and stops. The camera 72 is adjusted in advance so as to project the end of the partition wall on the substrate 4 positioned on the table 6, detects the position of the concave portion at the end by image processing, and changes its position from the camera reference point. Find the quantity la. On the other hand, the length lb between the reference point of the camera 72 and the discharge hole 44 positioned at the extreme end of the coating head 20 fixed to the holder 22 when it is at the predetermined Y-axis coordinate position Ya is adjusted in advance. Since it is measured and input to the overall controller 60 as information, when the positional change amount la of the partition wall recess from the camera reference point is transmitted from the image processing device 74, the ejection hole located at the end of the coating head 20 is transmitted. 44 calculates a Y-axis coordinate value Yc that is directly above the recess at the end of the partition wall (for example, Yc = Ya + lb−la), and moves the coating head 20 to that position. The camera 72 can have the same function even when attached to the coating head 20 or the holder 22.
[0088]
During this time, the height sensor 40 detects the vertical position of the top of the partition wall 4 of the base material 4 and calculates the height of the top of the partition wall 4 of the base material 4 from the position difference from the top surface of the table 6. By adding the gap value between the coating head 20 ejection hole and the top of the partition wall 4 of the base material 4 given in advance to this height, a value to be lowered on the Z-axis linear sensor of the coating head 20 is calculated. Then, the application head is moved to that position. As a result, even if the top position of the partition wall on the table 6 changes for each substrate, the gap between the ejection hole 20 that is important for coating and the top of the partition wall on the substrate can always be kept constant. .
[0089]
Next, the operation of the table 6 is started toward the coating head 20, and the speed is increased to a predetermined coating speed before the coating start position of the substrate 4 reaches just below the discharge hole of the coating head 20. The distance between the operation start position of the table 6 and the application start position must be sufficiently secured so that the speed can be increased to the application speed.
[0090]
Further, a position sensor 68 for detecting the position of the table 6 is arranged until the application start position of the base material 4 reaches just below the discharge hole 44 of the application head 20, and when the table 6 reaches this position, The pressure control valve 82 is driven to the open state, and compressed air that has been adjusted to a predetermined pressure by the pressure reducing valve 84 is supplied to the coating head 20. The pressurized air supplied to the coating head 20 is introduced into the space 202, and pressure is applied to the liquid surface of the discharge manifold unit 200, and the coating liquid 42 is discharged from the discharge holes 44. The position where the supply of the coating liquid 42 is started can be adjusted by changing the installation location of the position sensor 68. If an encoder is connected to the motor or the feed screw instead of the position sensor 68 or a linear sensor is attached to the table, the same thing can be done even if the value is detected by the encoder or the linear sensor.
[0091]
The application is performed until the application end position of the substrate 4 comes to a position immediately below the discharge hole 44 of the application head 20. That is, since the base material 4 is always placed at a predetermined position on the table 6, (a) for example, 5 mm before the application end position of the base material 4 is just below the discharge hole 44 of the coating head 20, or ( b) The position sensor 68 and its encoder value are set in advance in the position of the table 6 corresponding to the position just below, and when the table 6 comes to the position corresponding to (a), the overall controller 60 controls the pressure. A drive command for closing the valve 82 is issued, the supply of compressed air is stopped, coating is performed up to the position (b), and then the coating head 20 is raised when the table 6 comes to the position corresponding to (b) to complete the application. The coating liquid 42 is completely covered. When the coating liquid 42 is a relatively high-viscosity liquid, it is difficult to stop the application liquid discharge from the application head discharge hole 44 due to the residual pressure instantaneously by simply stopping the supply of compressed air. Therefore, if the supply of compressed air is stopped and the pressure in the space 202 in the coating head is set to atmospheric pressure, the discharge of the coating liquid from the discharge hole 44 can be stopped in a short time. It is preferable to provide such a function or to provide an air release valve between the pneumatic control valve 82 and the coating head 20.
[0092]
23 and 24, the table 6 continues to operate even after passing the application end position, and stops when it reaches the end position. The coating liquid supply process to the coating head is performed with the table 6 stopped. Since the coating liquid level in the coating head 20 has already been lowered by the coating operation, the non-contact displacement meter 88 detects the coating liquid level and transmits a detection signal to the overall controller 60. The overall controller 60 transmits a coating liquid supply command to the supply device controller 58 from the amount of decrease in the coating liquid level. The supply device controller 58 operates the coating liquid control valve 48 and the pneumatic control valve 54 to supply the pressurized air to the coating liquid tank 97, and supplies the required amount of coating liquid from the coating liquid tank 97 through the supply hose 46 and the filter 47. Inject into. The coating liquid filled in the supply manifold section 206 flows from the slit-shaped coating liquid supply port 204 to the discharge manifold section 200 and is supplied uniformly in the longitudinal direction. In this case, the entire controller 60 controls the supply device controller 58 by feedback control while sequentially detecting the liquid level, instead of supplying the coating liquid amount calculated in advance from the pressure and time, and reaches a predetermined liquid level. It is also possible to stop the supply of the coating liquid at the time when it is done. Furthermore, in this case, when there is a time delay for the liquid level to become horizontal due to the viscosity of the coating liquid, it is preferable to perform a predictive control in which the supply is stopped at a position lower than a predetermined liquid level height at which the delay time is predicted in advance. After supplying a predetermined amount of coating liquid, the coating liquid control valve 48 and the compressed air control valve 54 are closed, and the coating liquid supply is stopped. At this time, the liquid level in the supply manifold unit 206 is high and the liquid level in the discharge manifold unit 200 is low. However, by closing the coating liquid control valve 48 on the upstream side, the discharge manifold unit 200 is moved to the discharge manifold unit 200. A large amount of coating liquid does not leak.
[0093]
If there is still a part to be applied next, the application head 20 is moved in the Y-axis direction by the application width (nozzle pitch × number of holes) to the start position to be applied next. The coating is performed in the same procedure except that is moved in the opposite direction. If application is performed in the same movement direction of the table 6 as in the first time, the application head 20 moves in the Y-axis direction to the start position to be applied next, and the table returns to the X-axis preparation position.
[0094]
When the coating process is completed, the table is moved to a place where the substrate 4 is transferred by the unloader and stopped. After the adsorption of the substrate 4 is released and the atmosphere is released, the lift pins are raised and the substrate 4 is moved to the table 6. Pull it away from the surface and lift it up.
[0095]
At this time, the lower surface of the base material 4 is held by an unloader (not shown), and the base material 4 is transported to the next step. When the base material 4 is delivered to the unloader, the table 6 lowers the lift pins and returns to the origin position.
[0096]
In the above embodiment, the base material 4 is moved in the X-axis direction and the application head 20 is moved in the Y-axis and Z-axis directions. However, the application head 20 and the base material 4 are relative to each other. The table 6 and the application head 20 may be moved in any combination as long as the structure and type can be moved three-dimensionally.
[0097]
For example, in the above-described embodiment, the application is performed by moving the table 6 and moving the unevenness in the pitch direction by moving the application head 20. However, the application is performed by moving the application head 20 and moving the unevenness in the pitch direction. May be moved by moving the table 6.
[0098]
In addition, the case where one kind of coating liquid is applied to the stripe-shaped concave portions formed on the surface of the base material has been described in detail, but the present invention is also applicable to the case of simultaneously applying phosphors of three colors such as red, blue, and green. The invention can be applied, and can also be applied to the case where it is applied to a lattice-shaped recess formed on the surface of the substrate.
[0099]
Furthermore, as coating conditions that can be used, the coating speed may be any speed, but is preferably 0.1 to 10 m / min, and more preferably 0.5 to 8 m / min.
[0100]
【Example】
Hereinafter, the present invention will be specifically described with reference to examples. However, the present invention is not limited to this. In the examples, the concentration (%) is% by weight unless otherwise specified.
[0101]
Example 1
Using a photosensitive silver paste, 1600 address electrodes having a line width of 60 μm and a pitch of 220 μm were formed on a glass substrate (“PD200” manufactured by Asahi Glass Co., Ltd.). Next, after applying a glass paste consisting of 50% by weight of glass powder, 15% of titanium oxide, 20% of ethyl cellulose, and 15% of solvent on the electrode, it was baked to form a dielectric layer. Further, 961 barrier ribs having a pitch of 220 μm, a height of 150 μm, and a width of 60 μm were formed on the dielectric layer by a photosensitive paste method so that an electrode was disposed in the center between the barrier ribs. As described above, 30 substrates on which address electrodes, dielectric layers, and barrier ribs were formed were prepared.
[0102]
A phosphor paste composed of 39 g of phosphor powder, 8 g of binder polymer (ethylcellulose), and 53 g of solvent (terpineol) was produced. The phosphor powders are red: (Y, Gd, Eu) BO3 (cumulative average particle diameter: 2.7 μm, specific surface area: 3.1 m2 / cm3), green: (Zn, Mn) 2SiO4 (cumulative average particle diameter: 3.6 μm, (Specific surface area 2.5 m 2 / cm 3), blue: (Ba, Eu) MgAl 10 O 17 (cumulative average particle diameter 3.7 μm, specific surface area 2.3 m 2 / cm 3) was used. Each component of the organic component was dissolved in water while heating at 60 ° C., after which phosphor powder was added and kneaded with a kneader to prepare a paste. The viscosity was 35 Pa · s.
[0103]
The paste prepared as described above was applied in stripes on 30 glass substrates on which partition walls and the like were formed.
[0104]
As the coating liquid coating apparatus according to the present invention, a phosphor paste was applied between the partition walls using a coating apparatus as shown in FIG. First, a red phosphor paste was applied between predetermined partitions. The distance between the tip surface of the coating head and the upper end of the partition was set to 100 μm. Then, the air pressure (discharge pressure) was adjusted to 0.4 MPa by the pressure reducing valve, and the phosphor paste was discharged from the 16 discharge holes and applied between the partition walls while the coating head was running in parallel with the partition walls. Thereafter, the coating head was moved 10.56 mm in a direction perpendicular to the partition wall direction at the position where coating (16 pieces) was completed once. At this time, when the level of the phosphor paste in the coating head was detected with a laser displacement meter, it decreased by about 3 mm, and the amount of fluorescence calculated for the decrease was applied to the coating head by automatic control from the sequencer that is the overall controller. Body paste was supplied. For transporting the phosphor paste, pressurized air was injected into a coating liquid tank as a coating liquid supply source, and the coating liquid was supplied to the coating head at that pressure. An electromagnetic pinch valve was used as a control valve for supplying the phosphor paste.
[0105]
The phosphor paste is first supplied to the supply manifold in the coating head, the coating liquid is filled in the longitudinal direction of the coating head, and then the phosphor paste is discharged from the slit-shaped coating liquid supply port into the coating head. Supplied to the manifold section.
[0106]
The longitudinal length of the supply manifold portion was the same as the longitudinal length of the discharge manifold portion in the coating head. The slit shape that is the coating liquid supply port has a longitudinal opening length that is the same as the longitudinal length of the discharge manifold in the coating head, a height opening length of 0.5 mm, and a slit length of 14 mm.
[0107]
The supplied phosphor paste was collected in the discharge manifold part in the coating head without biting air, and the liquid level was able to be supplied uniformly and in a short time while maintaining almost horizontal state in the discharge manifold part immediately after supply. .
[0108]
After confirming the return of the liquid level with a laser displacement meter, a second coating was subsequently applied between the partition walls. Thereafter, since the laser displacement meter reached the lower limit value, the phosphor paste was replenished. In this case as well, the liquid level could be supplied in a short time while maintaining a substantially horizontal state.
[0109]
This was repeated 20 times, and 320 pieces were applied to predetermined positions of the red phosphor. After the completion of coating, the coated surface was turned up and dried at 80 ° C. for 40 minutes. Next, 320 blue phosphor pastes were similarly applied between adjacent barrier ribs coated with red phosphors and dried. Further, 320 green phosphor pastes were similarly applied between adjacent barrier ribs coated with blue phosphor and dried. The above-described phosphor pastes of the respective colors were applied and dried on 30 substrates. And it baked for 30 minutes at 500 degreeC, and obtained 30 backplates as a member for plasma display panels of this invention.
[0110]
When the side surface thickness and the bottom surface thickness of the phosphor layer were observed with an electron microscope, the phosphor layers of each color could be formed to a thickness of 20 ± 5 μm on both the side surface and the bottom surface of any of the 30 back plates.
[0111]
Further, after the obtained back plate was combined with the front plate, it was prepared by sealing and gas filling, and a driving circuit was connected to prepare 30 plasma display panels. For any of the plasma display panels, there was no luminance unevenness due to variations in the discharge amount, and a plasma display panel having good display characteristics and stability was obtained.
[0112]
After the coating operation was completed, the coating head was removed from the coating apparatus, and the bolts that fastened the upper member and the lower member were removed and disassembled for cleaning. In particular, since it can be disassembled from the slit which is the supply port to the discharge manifold, it is easy to visually observe the surface that the phosphor paste is in contact with, and the cleaning operation can be performed smoothly and easily after cleaning. Met.
[0113]
Assembly was performed for the next application operation. Basically, the upper member and the lower member were combined and fastened with bolts, and the assembly work could be completed in a short time.
[0114]
Example 2
The coating liquid coating apparatus of the present invention has a cross-sectional shape as shown in FIG. 22 as an overall configuration and a coating head as shown in FIG. 28, and the coating head is longer in the width direction than the coating area on the glass substrate. Was moved relative to the glass substrate once to apply the phosphor paste between the barrier ribs in the same manner as in Example 1 above using a long coating head that completed the coating on the glass substrate. First, a red phosphor paste was applied between predetermined partitions. The distance between the tip surface of the coating head and the upper end of the partition was set to 100 μm. Then, the air pressure (discharge pressure) was adjusted to 0.4 MPa by a pressure reducing valve, and the phosphor paste was discharged from 1032 discharge holes and applied between the partition walls while the coating head was running in parallel with the partition walls. At this time, when the level of the phosphor paste in the coating head was detected with a laser displacement meter, it decreased by about 3 mm, and the amount of fluorescence calculated for the decrease was applied to the coating head by automatic control from the sequencer that is the overall controller. Body paste was supplied. For transporting the phosphor paste, pressurized air was injected into a coating liquid tank as a coating liquid supply source, and the coating liquid was supplied to the coating head at that pressure. An electromagnetic pinch valve was used as a control valve for supplying the phosphor paste.
[0115]
The phosphor paste is first supplied to the supply manifold in the coating head, the coating liquid is filled in the longitudinal direction of the coating head, and then the phosphor paste is discharged from the slit-shaped coating liquid supply port into the coating head. Supplied to the manifold section.
The longitudinal length of the supply manifold portion was the same as the longitudinal length of the discharge manifold portion in the coating head. The slit shape that is the coating liquid supply port has a longitudinal opening length that is the same as the longitudinal length of the discharge manifold in the coating head, the height opening length is 0.75 mm, and the slit length at the center in the width direction. Was 23 mm, and the slit length at the end in the width direction was 22 mm.
Fifteen stays were formed on the lower member and fastened with the upper member and bolts. The shape of the stay was a cylindrical shape with an outer diameter of 14 mm, and the slit length on the downstream side of the stay was 5 mm. The phosphor paste flows into the slit-shaped coating liquid supply port, is divided by the stay, and merges at the portion where the slit length downstream of the stay is 5 mm, and is uniform in the width direction from the slit-shaped coating liquid supply port It came out.
[0116]
The supplied phosphor paste was collected in the discharge manifold part in the coating head without biting air, and the liquid level was able to be supplied uniformly and in a short time while maintaining almost horizontal state in the discharge manifold part immediately after supply. .
[0117]
After confirming the return of the liquid level with a laser displacement meter, the second coating was subsequently performed between the partition walls of the next glass substrate. Thereafter, since the laser displacement meter reached the lower limit value, the phosphor paste was replenished. In this case as well, the liquid level could be supplied in a short time while maintaining a substantially horizontal state.
This was repeated 30 times, and after coating was completed, the coated surface was turned up and dried at 80 ° C. for 40 minutes. Next, the blue phosphor paste was similarly repeated 30 times between the adjacent barrier ribs coated with the red phosphor, applied and dried. Further, the green phosphor paste was similarly repeated 30 times between the adjacent barrier ribs coated with the blue phosphor, applied and dried. And it baked for 30 minutes at 500 degreeC, and obtained 30 backplates as a member for plasma display panels of this invention.
When the side surface thickness and the bottom surface thickness of the phosphor layer were observed with an electron microscope, the phosphor layers of each color could be formed to a thickness of 20 ± 5 μm on both the side surface and the bottom surface of any of the 30 back plates.
[0118]
Further, after the obtained back plate was combined with the front plate, it was prepared by sealing and gas filling, and a driving circuit was connected to prepare 30 plasma display panels. For any of the plasma display panels, there was no luminance unevenness due to variations in the discharge amount, and a plasma display panel having good display characteristics and stability was obtained.
[0119]
After the coating operation was completed, the coating head was removed from the coating apparatus, and the bolts that fastened the upper member and the lower member were removed and disassembled for cleaning. In particular, since it can be disassembled from the slit which is the supply port to the discharge manifold, it is easy to visually observe the surface that the phosphor paste is in contact with, and the cleaning operation can be performed smoothly and easily after cleaning. Met.
Assembly was performed for the next application operation. Basically, the upper member and the lower member were combined and fastened with bolts, and the assembly work could be completed in a short time.
[0120]
【The invention's effect】
The coating head and the coating apparatus of the present invention include a discharge manifold portion, a discharge opening opening from the inside to the outside of the discharge manifold portion, and a slit-shaped coating for supplying a coating liquid to the discharge manifold portion. Since the liquid supply port is configured, the opening area of the coating liquid supply port can be increased, and more coating liquid can be supplied at high speed and uniformly in the width direction. And the operation cycle time at the time of application | coating is shortened, and productivity improves.
[0121]
In addition, since a supply manifold part for diffusing the coating liquid in the width direction is formed on the upstream side of the coating liquid supply port, the supply liquid can be evenly supplied in the width direction, and the coating liquid collected in the discharge manifold part The flow stability in the width direction is improved and the discharge becomes uniform, so that the quality of coating is improved.
[0122]
Further, the coating method of the present invention has a thixotropy by diffusing the coating liquid in the coating head width direction and supplying the coating liquid to the discharge manifold portion from the slit-shaped coating liquid supply port located downstream. Even in the case of supplying the coating liquid, it is possible to minimize the non-uniformity of the viscosity of the coating liquid in the discharge manifold portion, so that the discharge is uniform and the quality of the coating is improved.
[0123]
In addition, the coating head and the coating apparatus of the present invention are configured such that the coating head can be divided into at least two members on a plane parallel to the slit surface located between the opposing slit surfaces in the coating liquid supply port. As a result, the cleaning performance is improved, the cleaning time is shortened, and the coating defects due to dust are reduced, so that the productivity and quality can be improved.
[0124]
Further, since at least one slit-shaped coating liquid supply port is formed in the manifold section width direction, even when coating with a coating head longer in the width direction, more coating liquid is uniformly supplied at high speed. be able to.
[0125]
Furthermore, since at least one surface forming the slit-shaped coating liquid supply port is connected to the uppermost portion of the surface forming the supply manifold portion, air accumulates in the upper portion of the supply manifold portion. Even in such a case, since the liquid level of the discharge manifold portion does not change drastically at the time of discharge, it becomes possible to detect and manage the liquid level stably and accurately.
[0126]
Furthermore, since the stay is arranged so that a slit is formed at least downstream in the coating liquid flow direction of the stay, the coating liquid flowing in from the supply manifold section passes through the slit-shaped coating liquid supply port, and is used for discharge. When it is supplied to the manifold section, the merging ends in the slit-shaped coating liquid supply port before merging in the discharge manifold section, so that the time during which the coating liquid is divided by the stay can be shortened, and in particular thixotropy In the coating liquid which has, the bad influences, such as a viscosity change, can be suppressed to the minimum, and a coating liquid can be supplied in a substantially uniform state in the width direction.
[0127]
That is, as described above, the operation cycle time is shortened, stable coating is possible over a long period of time, and a series of operations such as cleaning and assembly of the coating head is facilitated, resulting in extremely high productivity, High quality and cost reduction are possible.
[Brief description of the drawings]
FIG. 1 is a schematic view showing a configuration around a table and a coating head of a coating liquid coating apparatus according to an embodiment of the present invention.
FIG. 2 is a schematic diagram of an AA cross section of a coating liquid reservoir portion (discharge manifold portion) 200 which is the coating head of the present invention in FIG.
FIG. 3 is a cross-sectional perspective view of a coating head according to an embodiment of the present invention.
4 is a schematic diagram of a B-B cross section of a supply manifold section 206 which is a coating head of the present invention in FIG. 1. FIG.
FIG. 5 is a schematic diagram of a supply manifold section according to another embodiment of FIG.
6 is a schematic diagram of a supply manifold section according to still another embodiment of FIG.
7 is a schematic schematic view of a CC cross section of FIG.
FIG. 8 is a schematic diagram according to another embodiment of FIG. 7;
FIG. 9 is a schematic diagram according to still another embodiment of FIG. 7;
FIG. 10 is a schematic diagram of one embodiment in which FIGS. 8 and 9 are combined.
FIG. 11 is a schematic diagram according to still another embodiment of FIG. 4;
12 is a schematic diagram of a cross section taken along line EE in FIG. 1; .
FIG. 13 is a schematic diagram according to another embodiment of FIG.
14 is a schematic diagram according to still another embodiment of FIG.
FIG. 15 is a schematic diagram according to still another embodiment of FIG. 4;
FIG. 16 is a schematic diagram according to another embodiment of FIG. 15;
17 is a schematic diagram of a DD cross section in FIG. 11. FIG.
18 is a schematic diagram according to another embodiment of FIG.
FIG. 19 is a schematic view according to another embodiment of the coating apparatus of the present invention.
FIG. 20 is a schematic diagram according to another embodiment of FIG. 17;
FIG. 21 is a schematic diagram according to another embodiment of FIG. 20;
22 is an overall perspective view of the coating liquid coating apparatus according to FIG. 1;
23 is a schematic cross-sectional view of the coating head in the apparatus of FIG. 1 as viewed from the coating direction.
FIG. 24 is a schematic cross-sectional view of an embodiment of the present invention in which the coating liquid amount detection means is coating head weight measurement.
FIG. 25 is a diagram schematically showing the supply / supply timing of the coating liquid from the coating liquid tank 97 to the coating head 20;
FIG. 26 is a schematic cross-sectional view according to another embodiment of the supply manifold portion 206 of the coating head of the present invention.
FIG. 27 is a schematic cross-sectional view according to another embodiment of the coating head of the present invention.
FIG. 28 is a schematic sectional view according to another embodiment of the supply manifold portion 206 of the coating head of the present invention.
FIG. 29 is a schematic sectional view according to another embodiment of FIG. 28;
30 is a schematic cross-sectional view according to still another embodiment of FIG.
[Explanation of symbols]
Second stage
4 Base material
6 tables
8 Guide groove rail
10 Feed screw
11 Connector
12 Bearing
14 universal joints
16 AC servo motor
19 Dividing plane
20 Application head (nozzle)
20a Coating head upper member
20b Coating head lower member
20c Coating head middle member
22 Holder
24 horizontal bars
26 Linear actuator
28 Lifting bracket
29 Telescopic rod
30 Lifting mechanism
32 Y-axis moving bracket
34 prop
36 Width direction moving mechanism
38 Sensor support
40 Height sensor
42 Coating liquid
44 Discharge opening (discharge hole)
46 Coating liquid supply hose
47 Filter
48, 48a, 48b Coating liquid control valve
50 Air pressure source
54 Pneumatic control valve
58 Feeder controller
60 Overall controller
62 Motor controller
66 sensors
68 Position sensor
70 props
72 cameras
74 Image processing device
76 Actuator for lifting mechanism
78 Actuator for width direction moving mechanism
81 Compressed air supply hose
82 Pneumatic control valve
84 Pressure reducing valve
86 Air pressure source
88 Non-contact displacement meter
90 Sensor bracket
92 Transparent plate
96 Weight detection sensor
97 Coating liquid tank
200 Discharge manifold (coating liquid reservoir)
201 Fastening bolt
202 Space
203 Slit length
203a, 203b Slit
204, 204a, 204b Coating liquid supply port
205 connecting bolt
206 Manifold section for supply
207 Second supply manifold
206a Supply manifold supply port for supply manifold
208, 208a, 208b, 208c Stay
209 Coating liquid supply port

Claims (25)

A discharge manifold portion, a discharge opening portion provided on the lower surface and opening from the inside to the outside of the discharge manifold portion, a pressurized air supply portion provided at an upper portion of the discharge manifold portion, and a coating liquid for the discharge manifold portion An application head characterized by having a slit-shaped application liquid supply port provided in a range to be immersed therein and supplying an application liquid to the discharge manifold section. 2. The coating head according to claim 1, wherein a supply manifold section that diffuses the coating liquid in a width direction of the coating head is formed upstream of the coating liquid supply port. 3. The coating according to claim 1 , wherein the upper end of the slit-shaped coating liquid supply port is at the same height as the uppermost surface of the supply manifold section or at a position higher than the uppermost surface of the supply manifold section. head. The coating head according to claim 1, wherein the coating liquid supply port is formed on a side surface of the discharge manifold portion. The coating head according to claim 4, wherein a plurality of the coating liquid supply ports are formed in the width direction of the discharge manifold portion . The coating liquid supply port, sandwiching a discharge manifold, the coating head according to claim 4 or 5, characterized in that it is formed on both sides. Coating head according to any one of claims 1 to 6, the discharge opening of the coating head is characterized in that at least one discharge hole. The coating head of the coating liquid according to any one of claims 1 to 7, wherein the coating solution is divided can be configured at the feed port. A plurality of coating liquid supply ports are formed in the width direction of the discharge manifold portion, and a stay for connecting the upper member and the lower member is provided between the plurality of coating liquid supply ports. The coating head according to claim 8, wherein the coating head is characterized. The coating head according to claim 9, wherein a confluence portion for coating liquid is provided on the discharge manifold portion side of the stay. To a table for fixing the substrate, a coating head that is provided facing the substrate and that applies a predetermined amount of coating liquid to the substrate, a moving means that relatively moves the table and the coating head in three dimensions, and a coating head An apparatus for applying a coating liquid to a substrate provided with a coating liquid tank as a supply source of the coating liquid, wherein the coating head according to any one of claims 1 to 10 is used. . 12. The coating liquid according to claim 11, wherein a dimension of the coating head in a direction perpendicular to the coating direction is longer than a coating liquid coating area of the substrate and has a discharge opening corresponding to the coating area. Coating device. 13. The coating liquid coating apparatus according to claim 11, wherein the substrate is a light emitting substrate for plasma display, and the coating liquid is a paste containing phosphor powder. An apparatus for manufacturing a member for a plasma display panel, comprising the coating apparatus according to claim 13. In a coating liquid coating method in which a coating liquid is applied to a base material while relatively moving between the base material and a coating head in which a plurality of discharge holes provided facing the base material are arranged in a substantially straight line. , said supply manifold portion formed in the coating head by supplying a coating liquid coating solution is diffused into the coating head width direction, soak downstream of the supply manifold section, and in the coating liquid discharge manifold from a slit-shaped coating liquid supply port provided in a range by supplying a coating solution to said discharge manifold reservoir of coating liquid, the lower surface of the coating head by supplying compressed air to the space portion of the discharge manifold top A coating liquid coating method, wherein a coating liquid is applied to a substrate by discharging the coating liquid from a plurality of discharge ports provided . The upper end of the slit-shaped coating liquid supply port is at the same height as the top surface of the supply manifold section or higher than the top surface of the supply manifold section, and the coating liquid in the supply manifold section is drawn from the coating liquid supply port. the method of applying the coating according to claim 1 4, characterized in that to flow out. The coating liquid application method according to claim 16, wherein the coating liquid supply port is formed on a side surface of the discharge manifold portion. The coating liquid application method according to claim 17, wherein a plurality of the coating liquid supply ports are formed in a width direction of the discharge manifold portion . The coating liquid application method according to claim 17 or 18 , wherein the coating liquid supply port is formed on both sides of the discharge manifold portion . The coating head, the coating liquid coating method of according to any one of claims 15 to 19, characterized in that said a structure that can be divided by the coating liquid supply port. The coating head includes an upper member and a lower member, a plurality of the coating liquid supply ports are formed in the width direction of the discharge manifold portion, and a stay that connects the upper member and the lower member between the plurality of coating liquid supply ports. The coating liquid coating method according to claim 20, wherein the coating liquid is provided. The coating liquid application method according to claim 21, wherein a confluence part of the coating liquid is provided on the discharge manifold part side of the stay. The dimension in the direction perpendicular to the relative movement direction of the coating head is longer than the coating liquid application region of the base material, and the coating liquid is completely applied to the base material by the relative movement of the coating head once. The method for applying a coating liquid according to any one of claims 15 to 22. Said substrate a light-emitting substrate for a plasma display, the coating liquid is a paste containing a phosphor powder, wherein the applied using The coating method according to any one of claims claim 15 to 2 3 A method for producing a member for a plasma display panel. Plasma display panel characterized by using a member for plasma display manufactured by the method according to claims 2 to 4.

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