JP4383268B2 - Spray coating method and spray coating apparatus - Google Patents

Description

  The present invention relates to a spray coating method and a spray coating apparatus for forming a coating film by spraying a coating liquid on a workpiece.

As an example of a conventional coating apparatus, a coating apparatus as shown in FIG. 4 is known (see, for example, Patent Document 1).
The coating apparatus shown in FIG. 4 includes a rotary table 102 disposed in a coating chamber 105, and a spray composed of a two-fluid nozzle that sprays coating liquid together with solvent vapor onto the surface of a workpiece 101 held by suction on the rotary table 102. A nozzle 104 is provided. The spray nozzle 104 has an injection port 104a into which solvent vapor is injected from the solvent vapor supply source 108, an injection port 104b into which coating liquid is injected from the coating liquid supply source 109, and one injection port 104c. The turntable 102 incorporates heating means for heating the entire workpiece placed on the turntable.

In order to spray coat the surface of the workpiece 101 using this coating apparatus, the rotating table 102 holding the workpiece 101 is rotated by the suction, and the spray port 104c of the spray nozzle 104 is placed on the rotating workpiece 101. The coating liquid applied to the workpiece 101 is heated by spraying the coating liquid together with the solvent vapor in the form of a mist, coating the coating liquid on the surface of the workpiece 101, and heating the turntable 102 by the heating means. By drying, a coating film is formed on the surface of the workpiece 101.
Japanese Patent Laid-Open No. 9-029158

However, when a conventional coating apparatus is used, a method of heating the rotating table 102 and heating the entire workpiece is employed as a method for drying the coating solution applied to the workpiece surface, so that the workpiece 101 has irregularities on the surface. When the coating liquid is one having a three-dimensional shape, it is difficult to make the entire surface uniform in temperature when the coating liquid applied to the workpiece surface is dried, which causes coating unevenness. Even if a material with high thermal conductivity is used as the workpiece material in order to uniformly dry the coating solution, the surface temperature of the workpiece varies due to the air current blown from the spray nozzle, and coating unevenness is inevitable. .
On the other hand, when applying the coating liquid to a workpiece with a non-flat surface, dripping occurs unless heating for promoting drying is performed.

The present invention has been made in view of the above circumstances, and even if the workpiece has irregularities on its surface or a three-dimensional structure, a coating film having a desired thickness can be formed without causing dripping. An object of the present invention is to provide a spray coating method that can be formed on the surface of the film.
Further, there is provided a spray coating apparatus capable of forming a coating film having a desired thickness on the surface of the workpiece without causing dripping even if the workpiece has an uneven surface or a three-dimensional structure. For the purpose.

The spray coating method of the present invention is a spray coating method in which a coating film is formed by spraying a coating liquid comprising a resist and a solvent on the surface of a workpiece having irregularities on the surface, the coating being absorbed by the workpiece, and A step of forming a coating film by spraying the coating liquid while locally irradiating a part of the workpiece with light having a wavelength in the range of 0.1 μm or more and less than 2.5 μm, which is not absorbed by the coating liquid. It is characterized by providing.
The spray coating method of the present invention is a spray coating method in which a coating film is formed by spraying a photosensitive coating liquid on the surface of a workpiece having irregularities on the surface, the coating liquid being absorbed by the workpiece and the coating liquid. Comprises a step of forming a coating film by spraying so as not to dry before the coating solution adheres to the workpiece while heating by locally irradiating a part of the workpiece with light having a wavelength that is not exposed to light. Features .
The spray coating method of the present invention is a spray coating method in which a coating film is formed by spraying a coating liquid composed of a resist and a solvent on the surface of a workpiece having a concavo-convex surface, which is 0.1 μm or more and less than 2.5 μm. A step of forming a coating film by spraying so that the coating solution does not dry before the coating liquid adheres to the workpiece while locally irradiating and heating a part of the workpiece with light having a wavelength in the range of To do .

The manufacturing method of the three-dimensional circuit board of the present invention is characterized by using the spray coating method of the present invention having any one of the above-described configurations .
Further, in the method of manufacturing a three-dimensional circuit board of the present invention having the above-described configuration, the coating is performed while locally irradiating a part of the workpiece with light having a wavelength that is absorbed by the workpiece and not absorbed by the coating solution. A step of forming a wiring pattern by a photolithography technique is provided after the step of spraying the liquid to form a coating film.

The spray coating apparatus of the present invention is a spray coating apparatus that forms a coating film by spraying a coating liquid on the surface of a work, and is mounted on a work support base on which the work is placed and the work support base. A coating nozzle for spraying a coating liquid onto the workpiece; a light source for locally irradiating a part of the workpiece with light having a wavelength that is absorbed by the workpiece and not absorbed by the coating solution; and the light source Light source moving means is provided for enabling the irradiation angle of the light applied to the work to be changed according to the shape of the work by moving the light source, and the light source sprays the coating liquid sprayed from the coating nozzle. The light can be emitted so as to cross an area, and the wavelength of the light of the light source is 0.1 μm or more and less than 2.5 μm .
The spray coating apparatus of the present invention is a spray coating apparatus that forms a coating film by spraying a photosensitive coating solution on the surface of a workpiece, and includes a workpiece support table on which the workpiece is placed, and a workpiece support table. A coating nozzle for spraying a coating liquid onto a workpiece placed thereon, a light source for locally irradiating a part of the workpiece with light of a wavelength that is absorbed by the workpiece and the coating liquid is not sensitized, Light source moving means is provided for enabling the irradiation angle of the light applied to the work to be changed according to the shape of the work by moving the light source, and the light source is sprayed from the coating nozzle. The light can be emitted so as to cross the spray area .

In the spray coating apparatus according to the present invention having any one of the above-described configurations, a plurality of the light sources are provided, and the irradiation position and / or the irradiation spot diameter of each of the light sources is variable.

In the spray coating method of the present invention, a coating film is formed by spraying the coating agent while locally irradiating a part of the workpiece with light having a wavelength that is absorbed by the workpiece and not absorbed by the coating solution. By forming, the coating solution does not dry in the middle (before reaching the workpiece surface), and can be dried immediately after the coating solution reaches the workpiece surface. A coating film is obtained. Further, when the coating liquid is a photosensitive material, it can be applied to a workpiece without being exposed to light, so that a coating film can be formed without adversely affecting subsequent processes.
In addition, it is possible to partially increase the thickness of the coating film by repeating the spraying of the coating liquid and the above spot-light irradiation on the portion where the coating thickness is to be increased. The thickness can be controlled, and a coating film having a desired thickness can be formed on the surface of the workpiece.

In the spray coating method of the present invention, the surface irradiated with the light can keep the surface temperature at a predetermined temperature. Therefore, even in application to a work having low thermal conductivity, as in the prior art. The surface temperature differs depending on the distance from the heating unit, and uneven coating does not occur, and a uniform coating film can be obtained.
If these methods are applied to a workpiece having a three-dimensional shape such as irregularities and slopes on the surface, the slope is partially heated by the above light, and the drying of the coating liquid is promoted by heating, thereby dripping the liquid. It is possible to obtain a coating film having a uniform thickness. Such an effect becomes more prominent as the workpiece is thicker and the height of the uneven step is higher. In addition, the coating film can be partially thickened by repeating spraying of the coating liquid and spot irradiation of the light at the portion where the film thickness is increased.
Therefore, according to the method of the present invention, even if the workpiece has irregularities on the surface or a three-dimensional structure, a coating film having a desired thickness is applied to the surface of the workpiece without causing dripping. Can be formed.
Further, when the coating solution is a photoresist, the requirement for uniformity becomes severe due to the subsequent process, and the diameter of the spray particles must be reduced. As a result, the adjustment range of the viscosity and the like is narrow. The present invention includes a step of forming a coating film by spraying the coating liquid while locally irradiating a part of the work with light having a wavelength that is absorbed by the coating liquid and not absorbed by the coating liquid. This method is effective, and the heating effect of the workpiece can be enhanced by setting the wavelength of the light in the range of 0.1 to 20 μm in the above step.

  According to the spray coating apparatus of the present invention, the above-described configuration enables it to be suitably used for carrying out the spray coating method of the present invention. The work has a surface with irregularities or a three-dimensional structure. Even if it exists, the coating film with the target thickness can be formed on the surface of the workpiece without dripping.

Next, embodiments of the present invention will be described in detail with reference to the drawings.
The present invention is of course not limited to the embodiments described below, and in the following drawings, the constituent parts are shown so that the scale of each constituent part can be easily shown in the drawings. The scale is changed every time.

  FIG. 1 is a diagram showing a schematic configuration of a spray coating apparatus according to an embodiment of the present invention. The spray coating apparatus according to the present embodiment is placed in a coating chamber 1 on a belt conveyor (work support base / light source relative movement means) 3 and a belt 3 a serving as a work support base provided on the belt conveyor 3. A coating nozzle 5 composed of a two-fluid nozzle that sprays the coating liquid on the workpiece 2 together with solvent vapor, and a light source 41 for locally irradiating a part of the workpiece 2 with a light 39 via a lens 40 and heating it. It is a thing of the schematic structure provided with.

  The belt conveyor 3 is configured to move the work 2 placed on the upper surface of the belt 3a through the coating chamber 1 by moving the belt 3a with a large number of rollers 3b. Further, by moving the belt 3a, the irradiation angle of the light 39 applied to the workpiece 2 placed on the belt 3a can be changed. The workpiece 2 is a substrate such as a silicon substrate, a printed substrate, a plastic substrate, a Cu substrate, a substrate with a metal layer, or a printed wiring board, or a substrate of this type having irregularities on the surface, and further, these recesses and projections. A shape having a slope 2a is used. The workpiece 2 is preferably colored in a color that promotes absorption of the light 39 emitted from the light source 41.

An application nozzle 5 composed of a two-fluid nozzle is disposed above the work support 3. A coating liquid supply pipe 5a to which the coating liquid 4 is supplied from a coating liquid supply source (not shown) is connected to the coating nozzle 5, and a regulator (not shown) for controlling the flow rate of the coating liquid is connected to the coating liquid supply pipe 5a. And an air operation valve 5b. The coating liquid supply source includes a container in which the coating liquid 4 is accommodated, and the inside of the container is pressurized by an N ₂ pressure system.
A solvent supply pipe 8a to which solvent vapor 9 is supplied from a solvent supply source (not shown) is connected to the coating nozzle 5, and a regulator (not shown) for controlling the flow rate of the solvent vapor is connected to the solvent supply pipe 8a. And an air operation valve 8b. The solvent supply source is provided with a container containing a solvent, and the inside of the container is pressurized by an N ₂ pressurization system and maintained at the saturated vapor pressure of the solvent, whereby the solvent is contained in the container. Steam is generated.

When the operation valve 5b is opened, the coating liquid in the container of the coating liquid supply source is injected into the coating nozzle 5 via the regulator and the valve 5b. On the other hand, when the air operation valve 8b is opened, the solvent vapor 9 generated in the solvent supply source is injected into the coating nozzle 5 via the regulator and the air operation valve 8b.
When the solvent vapor 9 and the coating liquid 4 are supplied to the coating nozzle 5 in this way, the mist-like coating liquid (coating liquid mist) 4a is mixed with the solvent vapor from the nozzle 5 through the nozzle 3 in the coating chamber 1. Sprayed toward.
The position of the coating nozzle 5 can be changed, and the spray angle of the coating liquid mist 4a can be changed.

The coating solution 4 includes a resist and a resist thinner (solvent) depending on the workpiece 2 placed on the workpiece support 3 and the treatment applied to the workpiece 2, and the resist includes a negative resist and a positive resist (i , G, h line) or the like.
As the solvent 9, a solvent contained in the coating solution 4 is used. For example, xylene, ethyl lactate, 3 methylmethoxypropionate (MMP), ethylethoxypropionate (EEP), acetone, n-butyl A solvent used as a resist thinner such as acetate (NBA), ethyl cellosolve acetate (ECA), propylene glycol monomethyl ether (PGME), propylene glycol monomethyl ether acetate (PGMEA) is used.
The amount of the coating liquid sprayed from the coating nozzle 5 is about 20 to 200 g / hour.

The light source 41 can move in the coating chamber 1 and the angle of the optical axis G of the light source 41 can be changed, so that the light 39 is irradiated onto the workpiece 2 placed on the belt 3a. It also has a function as a work support base / light source relative movement means for changing the angle. The lens 40 can be moved in accordance with the movement of the light source 41 and the angle of the optical axis G, and the angle can also be changed.
A controller 42 is connected to the light source 41. The controller 42 can control the position of the light source 41 and the optical axis G according to the application position of the coating liquid mist 4a on the workpiece 2.
The light source 41 is controlled by a controller 42 so that light 39 can be emitted so as to cross the spray area of the coating liquid mist 4 a sprayed from the coating nozzle 5. The light source 41 can change the irradiation angle of the light 39 applied to the workpiece 2 placed on the belt 3a by changing the position and the optical axis provided in the coating chamber 1.

As the light 39 emitted from the light source 41, light having a wavelength that is absorbed by the work 2 and not absorbed by the coating liquid or the solvent is used. For example, a 1.064 nm YAG laser (by pulse), a semiconductor laser of about 850 nm ,
It is preferable to use the light 39 having a wavelength in the range of 100 nm or more and 1.0 mm or less because the heating effect on the workpiece is high.
Further, when a coating liquid 4 having a narrow adjustment range such as a viscosity such as a photoresist is used, the light 39 emitted from the light source 41 should have a wavelength in the range of 0.1 μm to 20 μm. This is preferable in that the heating effect of the workpiece can be increased.

  In addition, a supply / exhaust unit 11 is provided in the coating chamber 1, and a decompression unit (not shown) for reducing the atmosphere in the coating chamber 1 is further provided.

Next, a spray coating method for forming a coating film on the workpiece 2 having irregularities on the surface using the spray coating apparatus shown in FIG. 1 will be described.
First, the atmosphere in the coating chamber 1 is decompressed by the decompression means.
Next, the belt conveyor 3 is driven, and the workpiece 2 placed on the belt 3 a is introduced into the coating chamber 1.
Next, as shown in FIG. 2, the light 39 emitted from the light source 41 is locally irradiated to the inclined surface 2a of the work 2 through the lens 40 to heat it, and the operation valves 5b and 8b are opened to inject the coating nozzle 5. The coating liquid mist 4a sprayed on the slope 2a is dried by spraying the coating liquid mist 4a onto the slope 2a of the workpiece 2 from the mouth.
Next, the light 39 emitted from the light source 41 is locally irradiated to the flat surface 2b of the workpiece 2 through the lens 40 to heat it, and the coating liquid mist 4a is applied to the flat surface 2b of the workpiece 2 from the spray nozzle of the coating nozzle 5. By spraying, the coating liquid mist sprayed on the flat surface 2b is dried.
Before spraying the coating liquid mist 4a on each part of the workpiece 2, the position of the light source 41, the optical axis G, and the position of the lens 40 are adjusted according to the shape of the part to which the coating liquid mist 4a is applied. Further, as shown in FIG. 2, the light 39 emitted from the light source 41 is adjusted so as to cross the spray area 45 of the coating liquid mist 4 a sprayed from the coating nozzle 5 and reach the surface of the workpiece 2.

  Next, the operation valves 5b and 8b are closed to stop the spraying of the solvent vapor and the coating liquid mist 4a from the coating nozzle 5, and forced exhaust is performed by the air supply / exhaust means 11 to reduce the solvent concentration in the coating chamber 1. When the drying of the coating film is further promoted by the above, a work 2 having a coating film with no thickness on the surface and a uniform thickness is obtained.

According to the spray coating method of this embodiment, the coating liquid mist 4a is sprayed on the heated portion while locally irradiating a part of the workpiece 2 with the light 39 having the wavelength as described above to heat the coating. By forming, the coating mist 4a is not dried before reaching the workpiece surface, and can be dried immediately after the coating liquid mist 4a reaches the workpiece surface. Even the workpiece 2 can form a uniform coating film.
In addition, by repeating the spraying of the coating liquid and the local irradiation of the light 39 on the portion where the thickness of the coating is desired to be increased, the thickness of the coating can be partially increased. A coating film can be formed on the surface of the workpiece 2.

In the spray coating apparatus of the above-described embodiment, the case where the coating nozzle 5 is composed of a two-fluid nozzle has been described. However, an application using an ultrasonic atomizing nozzle as the coating nozzle or a coating solution is applied. One fluid nozzle may be used. When an ultrasonic atomizing nozzle is used as the coating nozzle, it is preferable to form the coating film by spraying the coating liquid on a part of the work 2 and simultaneously irradiating and heating the light 39 at the same time. Further, when a one-fluid nozzle is used as a coating nozzle, a part of the workpiece 2 is locally irradiated with the light 39 and partially heated in advance, and the coating liquid is sprayed onto the heated portion. Is preferably formed.
Moreover, in the spray coat apparatus of the said embodiment, although the case where one light source was provided was demonstrated, two or more light sources may be provided, and the optical axis may each be variable. Further, the plurality of light sources may each have a variable irradiation position and / or irradiation spot diameter.
Moreover, in the spray coating apparatus of the said embodiment, although the case where the light source 41 was a laser source was demonstrated, as shown in FIG. 3, the ultraviolet light lamp is provided with the light source 51 provided with the reflector, or the xenon lamp and the reflector. Alternatively, the light source 51 may be used.
As the light 39 emitted from such a light source 51, for example, a near infrared ray of 0.75 μm to 4 μm can be mentioned. Note that near infrared rays may be absorbed by the workpiece 2 depending on the type of plastic when the workpiece 2 is a plastic substrate. Moreover, near infrared rays of 2.5 μm to 3.5 μm are easily absorbed by water and resin.

Moreover, as the workpiece 2 used in the spray coating method of the above embodiment, it is preferable to use a workpiece colored in a color that promotes absorption of the light 39 emitted from the light source from the viewpoint of improving the heating efficiency. Depending on 2, the workpiece itself may be added with an absorbent that absorbs the light 39.
For example, when the coating solution is a synthetic resin solution or a resist, the surface of the work 2 is colored with carbon black so that the wavelength of the light 39 is absorbed.

The spray coating method of the above embodiment can also be applied to a method of manufacturing a three-dimensional circuit board. In that case, a coating liquid composed of a resist and its solvent is used as the coating liquid 4, and a belt (work support base). As the work 2 to be placed on 3a, a work having irregularities and slopes on the surface is used.
Further, in this method of manufacturing a three-dimensional circuit board, the coating liquid mist is applied while locally irradiating a part of the work with light 39 having a wavelength that is absorbed by the workpiece and not absorbed by the coating liquid. A three-dimensional circuit board is obtained by providing the process of forming a wiring pattern with a photolithographic technique after the process of spraying and forming a coating film.

The figure which shows schematic structure of the spray coat apparatus of embodiment of this invention. Explanatory drawing of the spray-coating method of embodiment of this invention. Explanatory drawing of the spray-coating apparatus and spray-coating method of other embodiment of this invention. The schematic block diagram which shows the example of the conventional coating device.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Coating chamber, 2 ... Work, 2a ... Slope, 2b ... Flat surface, 3 ... Belt conveyor, 3a ... Belt which also serves as a work support stand, 3b ... Roll, 4 ... coating solution, 4a ... mist-like coating solution (coating solution mist), 5 ... coating nozzle, 5a ... coating solution supply pipe, 5b ... air operation valve, 8a ... Solvent supply pipe, 8b ... Air operation valve, 9 ... Solvent vapor, 11 ... Supply / exhaust means, 39 ... Light, 40 ... Lens, 41, 51 ... Light source, 42 ..Controller, 45 ... spray area.

Claims (8)

A spray coating method in which a coating film is formed by spraying a coating liquid composed of a resist and its solvent on the surface of a workpiece having irregularities on the surface,
A part of the workpiece is locally irradiated with light having a wavelength in the range of 0.1 μm or more and less than 2.5 μm, which is absorbed by the workpiece and not absorbed by the coating solution, and the coating solution is sprayed while being heated. A spray coating method comprising a step of forming a coating film. A spray coating method for forming a coating film by spraying a coating liquid having photosensitivity on the surface of a workpiece having irregularities on the surface,
The coating liquid is absorbed by the workpiece, and the coating solution is not exposed to light. A spray coating method comprising a step of forming a coating film . A spray coating method in which a coating film is formed by spraying a coating liquid composed of a resist and its solvent on the surface of a workpiece having irregularities on the surface,
A coating film is formed by spraying the coating liquid so that it does not dry before adhering to the workpiece while locally irradiating a part of the workpiece with light having a wavelength in the range of 0.1 μm or more and less than 2.5 μm. A spray coating method comprising the step of : The manufacturing method of the three-dimensional circuit board using the spray-coating method as described in any one of Claims 1 thru | or 3 .   After the step of forming a coating film by spraying the coating solution while locally irradiating a part of the workpiece with light having a wavelength that is absorbed by the workpiece and not absorbed by the coating solution, and then forming a coating film The method for manufacturing a three-dimensional circuit board according to claim 4, further comprising a step of forming a wiring pattern by a technique. A spray coating apparatus for forming a coating film by spraying a coating liquid on the surface of a work,
A workpiece support table on which the workpiece is placed, a coating nozzle for spraying a coating solution onto the workpiece placed on the workpiece support table, and light having a wavelength that is absorbed by the workpiece and not absorbed by the coating solution. A light source for locally irradiating and heating a part of the work, and a light source moving means for changing the irradiation angle of the light applied to the work according to the shape of the work by moving the light source Provided,
The light source is configured to be able to emit the light so as to cross the spray area of the coating liquid sprayed from the coating nozzle, and the wavelength of the light of the light source is 0.1 μm or more and less than 2.5 μm. A spray coat device. A spray coating apparatus for forming a coating film by spraying a photosensitive coating solution on the surface of a workpiece,
A workpiece support table on which the workpiece is placed; a coating nozzle for spraying a coating solution onto the workpiece placed on the workpiece support table; and a light having a wavelength that is absorbed by the workpiece and is not sensitized by the coating solution. A light source for locally irradiating and heating a part of the light source, and a light source moving means for changing the irradiation angle of the light applied to the work according to the shape of the work by moving the light source And
The spray coating apparatus, wherein the light source is configured to emit the light so as to cross a spray area of the coating liquid sprayed from the coating nozzle .   The spray coating apparatus according to claim 6 or 7, wherein a plurality of the light sources are provided, and an irradiation position and / or an irradiation spot diameter of each of the light sources is variable.

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