JPH094974A - Method and apparatus for drying coating film - Google Patents

Abstract

PURPOSE: To provide a coating drying apparatus that suppresses the occurrence of uneven temperature due to contact with an object to be coated, that provides excellently flat coatings and film thickness distribution, and that obtains high- quality coated films. CONSTITUTION: When an object 11 coated with coating liquid 14 is dried by heating, the area of contact with the object 11 coated with the liquid is varied with the progress of heating the object 11 coated with the liquid. In the case five hot plates 12 having a plurality of proximity pins 13 are used to dry an object coated with the liquid, the positions of the proximity pins 13 brought into contact with the object 11 coated with the liquid are varied from one hot plate 12 to another. Transported from one hot plate to another, the object 11 coated with the liquid is heated at each of the five hot plates for a processing cycle time of 3-240 seconds. The positions of contact with the proximity pins 13 on the object 11 coated with the liquid are scattered, and the occurrence of uneven temperature due to contact with the proximity pins 13 is thereby prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating film drying method and apparatus for heating a coating material coated with a coating liquid to dry the coating film.

[0002]

2. Description of the Related Art In the process of manufacturing electronic parts, for example, a coating liquid is applied to a plate-shaped coating object in a desired area and shape, and then the coating object is heated to dry the coating film. And a step of flattening.

As a heating device used in such a case, for example, a plurality of hot plates for heating are provided, a coating object is conveyed to each position at a predetermined takt time, and a plurality of hot plates are provided on each hot plate. There is known a configuration in which the object to be coated is dried by sequentially heating and touching it with a hot plate via the proxy pin of No.

In the drying device set in this way,
The object to be coated is successively conveyed to each position at a constant takt time, and the object to be coated and the coating solution are heated to dry the coating solution and flatten it.

However, in such a conventional drying device,
The position of the proxy pin on each hot plate
Since it is the same on all hot plates, there is a difference in temperature between the area of the coating object that is in contact with the proxy pin and the other area during the drying of the coating solution, and temperature unevenness may occur in this certain area. Yes, the flatness and quality of the coating film deteriorate.

As a method for heating and drying the coating material of this type, in addition to the method using the hot plate described above, the coating material to which the coating liquid is applied is carried into a drying oven, There is also known a structure in which a coating object is heated by heat conduction, convection, or radiation in a drying furnace.

A transport arm for transporting the coating object to each position in the drying furnace and a fixed arm for fixedly supporting the coating object at each position in the drying furnace are provided. Further, the object to be coated is mounted on the supporting pins which are respectively provided on the transfer arm and the fixed arm.

In the drying oven set in this way,
The object to be coated is sequentially conveyed to each drying position at a constant takt time, and the object to be coated and the coating solution are heated to dry the coating solution and flatten it.

However, in such a conventional drying device,
Since the supporting pins provided on the transfer arm and the fixed arm are the same at any position of the transfer arm and the fixed arm, a certain area of the coating object that is in contact with the supporting pin during the drying of the coating solution and other areas. There is a possibility that a difference in temperature will occur between the area and the area, and temperature unevenness may occur in this certain area, which is one of the causes of deterioration of the flatness and quality of the coating film in the area.

[0010]

As described above, according to the conventional method, the proxy pin provided on each hot plate,
Since the positions of the supporting pins provided on the transfer arm and the fixed arm in the drying oven are constant, the coating object may have a certain area between the certain area in contact with the proxy pin or the supporting pin and another area. There is a difference in temperature. For this reason, there is a problem that the temperature unevenness in this fixed region becomes remarkable and the flatness and quality of the coating film in this region may deteriorate.

The present invention has been made in view of the above problems, and suppresses the occurrence of temperature unevenness due to the contact of an object to be coated, the flatness and the thickness distribution of the coating are good, and the coating is of high quality. An object of the present invention is to provide a coating film drying method and an apparatus therefor capable of obtaining the following.

[0012]

Means for Solving the Problems The present invention changes a contact area of a coating material with a heating body when the coating material coated with a coating liquid is heated to dry the coating film. The support position of the support pin that supports the coating object in the drying furnace is changed.

[0013]

The present invention changes the contact area between the object to be coated and the heating element when heating the object to be coated with the coating solution by contact with the heating element, or in a drying oven. By changing the supporting position of the support pin used for supporting the object to be coated with respect to the object to be coated, the temperature uniformity of the object to be coated is eliminated and the coating film is dried uniformly.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

As shown in FIG. 1, a hot plate 12 as a heating element is provided at each of a plurality of heating positions for drying the coating object 11. On these hot plates 12,
A plurality of proxy pins 13 are provided respectively, and the coating object 11 coated with the coating liquid 14 is indirectly heated by the hot plate 12 via these proxy pins 13. That is, the coating object 11 is sequentially transported by the transport mechanism (not shown) onto the plurality of hot plates 12 provided at each position at a predetermined takt time, and is heated via the proxy pin 13. As a result, the coating liquid 14 coated on the coating object 11 is dried and flattened. Finally, the coating object 11 is conveyed to the cooling position, cooled sufficiently, and then taken out to the next step.

Here, the reason why each hot plate 12 is provided with a proxy pin 13 is to prevent the occurrence of a temperature gradient due to the direct contact between the object to be coated 11 and the hot plate 12. That is, if the proxy pin 13 is not provided, a sharp temperature gradient occurs between the contact surface with the hot plate 12 and the non-contact surface of the object to be coated 11, and the shape change such as warpage or bending occurs. Or, unevenness in drying of the coating liquid 14 may occur.
Further, the conveyance of the coating object 11 is hindered, which is a main cause of deterioration of coating quality and reduction of yield.

Therefore, each hot plate 12 is provided with a proxy pin 13 so that the coating object 11 is indirectly heated via the proxy pin 13.

Further, the arrangement positions of the proxy pins 13 are set to be different for each hot plate 12. That is, as shown in FIG. 1, since there are five positions, the arrangement of the proxy pins 13 on each hot plate 12 is changed as shown in FIG.

That is, the proxy pin 13 ₁ is located at the first position and the proxy pin 13 ₁ is located at the second position.
Position ₂ . Similarly, from the 3rd position to the 5th
The positions of the proxy pins 13 ₃ , 13 ₄ , 13 _{5 up to} the position are sequentially changed. Although only the installation position of one proxy pin has been described with reference to FIG. 2, the installation position is similarly changed for other proxy pins not shown.

In this way, when the coating object 11 after the coating solution 14 is coated is dried by the drying device in which the installation position of the proxy pin 13 is changed, the coating object 11 is moved to each position. The hot plate 12 having a high temperature of about 40 to 200 ° C. is sequentially conveyed for a predetermined tact time of 3 to 240 seconds, and each is placed on the proxy pin 13 and dried.
At this time, the contact position between the object to be coated 11 and the proxy pin 13 is different for each position. That is, the contact area between the object to be coated 11 and the proxy pin 13, which is a part of the heating element, is changed along with the transition of the heating time for the object to be coated 11 corresponding to the conveyance to each position. Therefore, it is possible to suppress the occurrence of temperature unevenness due to the difference in temperature between the area in contact with the proxy pin 13 of the object to be coated 11 and other areas during the drying of the coating film liquid as much as possible, and the flatness of the entire coating film. And maintain high quality.

Here, the coating liquid 14 coated on the object to be coated 11
In the case of actually drying the, the specific operating conditions such as the temperature and tact time of each hot plate 12 and the properties of the coating liquid are set as follows.

First, the temperature of the hot plate position 1 is 75 ° C. and the temperature of the hot plate position 2 is 80 ° C.
℃, the temperature of hot plate position 3 is 85 ℃, the temperature of hot plate position 4 is 90 ℃, the temperature of hot plate position 5 is 95 ℃, and the cooling temperature is 25 ℃, and the takt time is 40 seconds. Set.

The viscosity of the coating solution is 50 cP, the solvent boiling point is 117 ° C., the solvent vapor pressure is 50 mmH ₂ O, the solid content concentration is 5%, and the film thickness after drying is 0.5 μm.

Further, the diameter of the proxy pin 13 is 2 mm,
Height of 3mm, the planar shape of the coated object 11 is 450mm
× 500 mm.

The amount of change of the proxy pin 13 for each position, that is, the proxy pin 13 ₁ and the proxy pin 13
₂ and the distance between the proxy pins 13 ₃ ... 25 mm.

When the coating film was dried under the above conditions, the trace diameter of the proxy pin on the coating film was 15 to 20 mm in the conventional example in which the position of the proxy pin was constant, whereas it was 7 to 9 mm in this embodiment. It became smaller and the quality improved. Moreover, side effects such as poor transportation do not occur.

As described above, the contact area between the coated object 11 and the heating element is changed with the drying time of the object to be coated. The coating film can be dried with almost no deterioration of the flatness of the coating film or deterioration of the quality.

Next, another embodiment will be described with reference to FIGS.

As shown in FIG. 5, a drying oven 17 is used to dry the coating material 11, and the coating fluid 14 shown in FIG. It is carried in and dried by heat conduction, convection, and radiation in the drying furnace 17. In addition, as shown in FIG. 5, five drying positions 16 _{1 to} 16 ₅ and one cooling position 16 ₆ from the first to the fifth are provided in the drying furnace 17. It should be noted that the number of drying positions is not limited to five and may be set to about 2 to 10.

[0030] Also within the drying oven 17, the transfer arm 18 is provided for conveying the Hinurimakubutsu 11 in each position _{161-164 6,} to be coating material 11 that has been conveyed by the conveying arm 18 The fixed arm 19 that fixedly supports on each position 16 _{1 to} 16 ₆
As shown in FIG. 3, it is provided in parallel with the transfer arm 18. A plurality of support pins 20 and 21 are provided on the upper surfaces of the transfer arm 18 and the fixed arm 19 in the figure.

Here, the support pins 20 and 21 are provided to prevent the occurrence of a temperature gradient in the object to be coated 11, as in the case of the proxy pin 13. That is, the support pin 20,
If the object to be coated 11 is directly supported on the transfer arm 18 and the fixed arm 19 without providing the 21, each of the arms 18,
A sharp temperature gradient is generated between the contact surface with 19 and the non-contact surface, causing a change in shape such as warpage or bending of the object to be coated 11, or unevenness in drying of the coating liquid 14. Further, the conveyance of the coating object 11 is hindered, which is a main cause of deterioration of coating quality and reduction of yield.

Therefore, the transfer arm 18 and the fixed arm 19
Support pins 20 and 21 are provided on the respective surfaces so that the object to be coated 11 does not directly contact the surfaces of the transfer arm 18 and the fixed arm 19.

In this embodiment, further, these support pins 2
The mutual intervals of 0 and 21, that is, A, B, C shown in FIG.
The positions are set so that D, E, F, ... Are different from each other. By setting the positions of the support pins 20 and 21 in this manner, the support positions of the support pins 20 and 21 with respect to the coating object 11 are
It can be changed along with the transition of the heating time, that is, the transition of the conveyance to each of the positions 16 _{1 to} 16 ₆ .

In the drying oven 17 having a high temperature of 40 to 200 ° C. constructed as described above, the object 11 to be coated is dried at the drying positions 16 _{1 to} 16 ₅ by the transfer arm 18 at a takt time of 3 to 240 seconds. To the corresponding drying position.
It is supported and fixed on the fixed arm 19 by 16 _{1 to} 16 ₅ . Then, the coating object 11 and the coating liquid 14 are sequentially heated at the respective drying positions 16 _{1 to} 16 ₅ to dry and flatten the coating liquid.

Finally, the object to be coated 11 is cooled to the cooling position 16 ₆
After being transported to and cooled sufficiently, the coating object 11 is taken out to the next step.

Here, the object to be coated 11 is supported on the support pins 20 and 21, respectively, when being transported by the transport arm 18 and being supported and fixed by the fixed arm 19. In addition, the mutual spacing A, B, C, D, E, F, ... Of these support pins 20, 21 ...
Since that is situated set differently respectively, during transportation and the position 16 ₁ between each position _{161-164 6}
In each of the time supported and fixed in -16 _6, Hinurimakubutsu 11
The contact positions of the support pins 20 and 21 are different from each other.

Conventionally, since the mutual intervals A, B, C, D, E, F, ... Of the supporting pins 20 and 21 are equal to each other, they come into contact with the supporting pins 20 and 21 during the drying of the coating liquid 14. There is a difference in temperature between a certain area of the coating object 11 and another area, and temperature unevenness is remarkably generated in this certain area, which deteriorates the flatness and quality of the coating film. Membrane 11 and support pin 2
Contact position between 0,21 is because it differs in each of the time supported and fixed in the transport and at each position _{161-164 6} between the positions 16 ₁ to 16 _6, such a problem hardly occurs, A good coating state can be obtained.

Here, the coating liquid 14 applied to the object to be coated 11
Each position 16 in the drying oven 17 when actually drying
_{1-16 6} temperature and cycle time, etc. the nature of the coating solution, to set the specific implementation conditions as follows.

First, the temperature of the first drying position is set to 75.
℃, the temperature of the second drying position is 80 ℃, the temperature of the third drying position is 85 ℃, the temperature of the fourth drying position is 90 ℃, the temperature of the fifth drying position is 95 ℃, and the cooling position The temperature is set to 25 ° C and the takt time is set to 40 seconds.

The viscosity of the coating liquid is 50 cP, the boiling point of the solvent is 117 ° C., the vapor pressure of the solvent is 50 mmH ₂ O, the solid content concentration is 5%, and the film thickness after drying is 0.5 μm.

When the coating film was dried under the above-mentioned conditions, the trace diameter of the support pin on the coating film was 15 to 20 mm in the conventional example in which the spacing between the support pins was constant, whereas it was 7 to 9 m in this example.
It became as small as m and the quality was improved. Moreover, side effects such as poor transportation do not occur.

As described above, the contact area between the coated object 11 and the supporting pins 20 and 21 was changed with the drying time of the object 11, so that the flatness of the coated film due to the temperature unevenness. The coating film can be dried with almost no deterioration or deterioration.

[0043]

According to the present invention, when the coating liquid is dried, the contact position between the coated object and the heating body or the contact position between the coated object and the supporting pin in the drying oven is changed. Therefore, temperature unevenness is less likely to occur, and the coating film can be dried with almost no deterioration in the flatness of the coating film, deterioration in the film pressure distribution, and almost no deterioration in quality.

[Brief description of drawings]

FIG. 1 is a front view showing a coating film drying apparatus according to an embodiment of the present invention.

FIG. 2 is a plan view showing a positional relationship of proxy pins of the same as above.

FIG. 3 is a plan view showing a main part of another embodiment of the same.

FIG. 4 is a front view showing a main part of the same.

FIG. 5 is a front view showing the overall configuration of the same.

[Explanation of symbols]

 11 Coating object 12 Hot plate as heating element 17 Drying oven 20, 21 Support pin

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kiyoshi Kannai 1-9-2 Harara-cho, Fukaya-shi, Saitama Stock company Toshiba Fukaya electronics factory

Claims (4)

[Claims] 1. An object to be coated coated with a coating liquid is heated,
In the coating film drying method for drying the coating film, the coating object is heated by contact with a heating body, and the contact area between the coating object and the heating body is changed over time. A method for drying a coating film, characterized in that 2. A coating object coated with a coating solution is heated,
In the coating film drying method for drying the coating film, the coating object is loaded into a drying furnace and heated, and the supporting position of the supporting pin that supports the coating object in the drying furnace is heated for a heating time. A coating film drying device characterized in that it changes with the transition of. 3. A coating object coated with a coating solution is heated to
A coating film drying apparatus for drying the coating film, comprising: a plurality of heating bodies having different contact regions for heating the coating object by contact. 4. An object to be coated coated with the coating liquid is heated,
In a coating film drying apparatus for drying the coating film, a drying furnace for heating the coating target object and a plurality of supports for conveying and supporting the coating target object in the drying furnace at different intervals are provided. A coating film drying device characterized by being provided.