JP3974430B2 - Coating dryer - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a coating drying apparatus, and more particularly, to a coating drying apparatus suitable for forming a desired coating layer by heating and drying a coating agent applied on a substrate.
[0002]
[Prior art]
Conventionally, a coating apparatus such as a die coater has been generally employed as a means for applying various coatings on a long base made of a resin film called a web, paper, cloth, metal foil, or the like. .
[0003]
In such a coating apparatus, the base material is sequentially transported to a coating position by a plurality of roller-shaped transporting means, and the coating agent is applied to the surface of the base material by a coating means such as a die coater head at the coating position. After coating, the substrate is transported into a drying furnace of a drying apparatus, and the coating agent applied to the substrate is dried with hot air, and heated and dried by a heater such as a far infrared heater or a panel heater to solidify. It is supposed to be.
[0004]
The heater has various modes, for example, a rod-shaped heater in which a nichrome wire is incorporated as a heating element in a long ceramic pipe as a far-infrared radiator, and a ceramic plate as an infrared radiation surface A plate-like heater or a so-called sheathed heater formed so that bending can be easily performed is generally used.
[0005]
These heaters, for example, energize a heating element through an electrode terminal of the heater to generate heat, and transmit the heat of the heating element to a far-infrared radiator to radiate far-infrared temperature. Thus, the coating agent is formed so that it can be dried by heating.
[0006]
In addition, some far infrared radiation is energized directly through the electrode terminals to generate the far infrared temperature radiation, and thereby, the coating agent is heated and dried. .
[0007]
[Problems to be solved by the invention]
By the way, in the coating agent 2 applied to the base material, there are those containing a flammable solvent such as MEK, toluene, ethyl acetate and methanol, and such a coating agent is heated by the heat of the heater. When evaporating and filling the drying furnace as a gas, the coating agent gas (hereinafter abbreviated as “coating agent gas”) may explode when triggered by ignition or the like, which may cause a so-called explosion.
[0008]
The present invention has been made in view of such problems, and by arranging the electrode terminal of the heater outside the drying furnace, it is possible to effectively prevent a violent explosion, and thus to realize the manufacture of a safe product. An object of the present invention is to provide a coating drying apparatus that can perform coating.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, the coating drying apparatus according to claim 1 of the present invention is characterized in that it has a combustibility applied on a substrate by energization through an electrode terminal in a drying furnace. In a coating drying apparatus having a heater for heating and drying a coating agent containing a solvent, the electrode terminal is disposed outside the drying furnace, and outside the drying furnace where the electrode terminal is disposed, A removing means for removing at least the gas of the coating agent flowing out from the inside of the drying furnace from the vicinity of the electrode terminal is provided, and the substrate coated with the coating agent is provided in the drying furnace. A lid part that can be opened and closed and a part of the upper wall part can be opened and closed, a nonwoven fabric disposed in the lid part, and a water supply means for supplying moisture to the nonwoven fabric, and the coating agent Saturate the atmosphere in the furnace in contact with the coated surface of the substrate coated with Saturated holding means which is capable of holding the state provided to said drying oven, in that provided blower for drying and solidifying by blowing hot air to the coated surface of the substrate.
[0010]
And by adopting such a configuration, the electrode terminal can be prevented from being exposed to the atmosphere of a flammable coating agent gas filled in the drying furnace. Can be reliably prevented. In addition, the coating gas that has flowed out of the drying furnace from the inside of the drying furnace to the outside of the drying furnace can be appropriately removed from the vicinity of the electrode terminal, so that explosion can be prevented more effectively. Can do. Furthermore, the saturation holding means can promote the drying and solidification of the coating agent on the inner side by the heater while suppressing the drying and solidification of the coating agent surface, so that a good coating layer free from defects such as cracks can be formed. It can be formed quickly.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of a coating drying apparatus according to the present invention will be described with reference to FIGS. 1 to 4.
[0014]
As shown in FIG. 1, the coating drying apparatus 1 in this embodiment is a coating means (not shown) such as a die coder head for applying a predetermined coating to a base material by, for example, applying a coating liquid. Is provided with a box-shaped drying furnace 2 in which a continuous substrate S can be carried. In the drying furnace 2, a plurality of transport rollers 3 for transporting the substrate S are rotatably arranged by a driving source such as a motor (not shown). Further, a far infrared heater 4 is disposed between the respective transport rollers 3 as an example of a heater for heating and drying the base material S.
[0015]
The far-infrared heater 4 has a horizontal plate-shaped far-infrared radiator 5 made of an aluminum casting or the like having a predetermined thickness. A far-red ceramic coating 30 is formed on the surface of the far-infrared radiator 5. It has been subjected.
[0016]
The far-infrared radiator 5 is provided with a sheathed heater 7 as a heater body so as to be embedded therein.
[0017]
As shown in FIGS. 2 and 3, the sheathed heater 7 is a heating element made of stainless steel or the like, which is obtained by bending a long tubular body such as a pipe so that its planar shape is substantially U-shaped with a hollow shape. An insertion portion 8 is provided. Both end sides of the heating element insertion portion 8 are extended to the outside of the far-infrared radiator 5 so as to be along the width direction of the base material orthogonal to the transport direction of the base material S.
[0018]
A heating element 9 made of, for example, nichrome wire is inserted into the heating element insertion portion 8 so as to follow the shape of the heating element insertion portion 8. Electrode terminals 10 are connected to both ends of the heat generating body 9 to conduct predetermined energization to the heat generating body 9.
[0019]
In the present embodiment, the electrode terminal 10 is arranged outside the drying furnace 2.
[0020]
That is, as shown in FIG. 4, the side wall 2 a of the drying furnace 2 facing the side end surface of the far-infrared radiator 5 on the side of the terminal portion 10 has an inner peripheral edge rather than an outer diameter of the heating element insertion portion 8. A rectangular through hole 11 having a large diameter is formed, and the terminal portion 10 is guided to the outside of the drying furnace 2 through the through hole 11.
[0021]
Further, a shielding plate 12 parallel to the side wall 2a for shielding the gap between the heating element insertion portion 8 and the through hole 11 is provided at a portion corresponding to the through hole 11 of the heating element insertion portion 8. This shielding plate 12 is fixed to the side wall 2a by a fixing means 14 such as a screw or a flange lever.
[0022]
As a result, since the electrode terminal 10 can be prevented from being exposed to the atmosphere of the coating agent gas, the explosion of the coating agent gas is prevented from occurring due to discharge of the electrode terminal 10 or the like. Be able to.
[0023]
Although not shown, a drive power supply is connected to the electrode terminal 10, and the far infrared heater 4 is energized by the drive power supply via the electrode terminal 10. ing.
[0024]
Further, in the present embodiment, outside the drying furnace 2 in which the electrode terminal 10 is disposed, the coating agent gas flowing out from the drying furnace 2 is removed at least from the vicinity of the electrode terminal 10. A removing means 15 is provided.
[0025]
That is, as shown in FIG. 4, a box-shaped air purge chamber 16 constituting a part of the removing means 15 is disposed outside the drying furnace 2 and corresponding to the electrode terminal 10. It is arrange | positioned so that it may surround. A compressed air injection unit 17 such as a blower is disposed on the upper wall portion 16a of the air purge chamber 16, and the compressed air injection unit 17 compresses the compressed air toward the electrode terminal 10 disposed below. Is to be injected. The compressed air injection unit 17 is controlled so as to be energized only at the plus pressure with the pressure of the compressed air by a control circuit (not shown) provided with, for example, a pressure switch.
[0026]
Thereby, the coating gas passes through the slight gap formed between the shielding plate 12 and the heating element insertion portion 8 described above, for example, in the drying furnace 2 in which the electrode terminal 10 is disposed. Even if it flows out to the outside, the coating agent gas can be prevented from staying in the vicinity of at least the electrode terminal 10.
[0027]
Therefore, the explosion of the coating agent gas can be prevented more effectively.
[0028]
A CA sensor 20 is connected to the far-infrared radiator 5 as a temperature sensor, and the temperature of the far-infrared heater 4 can be detected by the CA sensor 20, and to the heating element 9 according to this temperature. By performing the energization control, the temperature in the drying furnace 2 can be maintained at a desired value.
[0029]
Returning to FIG. 1, in the drying furnace 2, a saturation holding means 22 for holding the atmosphere in the furnace in contact with the coating surface of the substrate S coated with the coating agent in a desired saturation state is disposed. Has been. The saturation holding means 22 has a lid portion 23 that can be viewed from the base material S. A non-woven fabric 31 for maintaining humidity is disposed in the lid 23, and water or an organic solvent can be supplied to the non-woven fabric 31 from the outside via a water absorption means such as a pipe (not shown). It can be done. In addition, the saturation holding means 22 is configured such that a part of the upper wall portion 23a of the lid portion 23 can be opened and closed to adjust the wetness as required. Accordingly, the far-infrared heater 4 can promote the drying and solidification of the coating agent on the inner side while suppressing the drying and solidification of the coating agent surface, so that a good coating layer without formation defects such as cracks can be formed. It can be formed quickly.
[0030]
In addition, a blower 24 for drying and solidifying by blowing hot air on the coated surface of the substrate S is suspended from the upper wall 2b of the drying furnace 2.
[0031]
Next, the operation of this embodiment will be described.
[0032]
In the case where the coating agent on the substrate S is heated and dried using the coating drying apparatus 1 in this embodiment, the heating element 9 is energized through the electrode terminal 10 so that the far-infrared heater 4 is predetermined. The base material S is carried into the drying furnace 2 from the upstream coating means in a state where the heat is generated at the temperature. Then, the substrate S is transported further downstream by the transport roller 3 while maintaining the surface of the coating agent in a saturated state by the saturation retaining means 22.
[0033]
At this time, due to the heat of the far-infrared heater 4, a part of the coating agent evaporates and vaporizes into the coating agent gas, and fills the drying furnace 2.
[0034]
However, in this embodiment, since the electrode terminal 10 of the far-infrared heater 4 is disposed outside the drying furnace 2, it is avoided that the electrode terminal 10 is exposed to the coating gas atmosphere. Can do. Thereby, the explosion of the coating agent gas due to the ignition of the electrode terminal 10 can be prevented.
[0035]
Further, even when the coating gas flows out of the drying furnace 2 where the electrode terminal 10 is disposed for some reason, the compressed air injection unit 17 disposed in the air purge chamber 16 is driven. By doing so, the coating agent gas can be removed from the periphery of the electrode terminal 10. Thereby, the explosion of the coating agent gas can be more effectively prevented.
[0036]
And the base material S by which the coating agent was dried in the drying furnace 2 is discharged | emitted to the winding part which is not shown in the downstream, and is wound up and accommodated by this winding part.
[0037]
Therefore, according to this embodiment, the electrode terminal 10 is disposed outside the drying furnace 2, so that the explosion of the coating agent gas can be reliably prevented.
[0038]
In addition, this invention is not limited to the thing of the said embodiment, A various change is possible as needed.
[0039]
For example, the present invention is not limited to the far-infrared heater described above, but can be applied to a case where a far-infrared heater having another configuration or a different type of heater from the far-infrared heater is used.
[0040]
Furthermore, the number of the drying furnaces is not limited to one, for example, a plurality of drying furnaces having different drying conditions such as the temperature of the heater are continuously provided at predetermined intervals in the conveying direction of the substrate S, and each drying furnace is provided. The electrode terminal of the heater inside may be arranged outside the drying furnace.
[0041]
【The invention's effect】
As described above, according to the coating drying apparatus according to claim 1 of the present invention, it is possible to appropriately prevent the explosion of the coating agent gas, and thus it is possible to realize the manufacture of a safe product. , Reliability can be improved. Furthermore, it is possible to quickly form a good coating layer free from defects such as cracks.
[Brief description of the drawings]
FIG. 1 is a schematic side view showing an embodiment of a coating drying apparatus according to the present invention. FIG. 2 shows a far-infrared heater in a substrate transport direction in an embodiment of a coating drying apparatus according to the present invention. Fig. 3 is a plan view of Fig. 2. Fig. 4 is a plan view of Fig. 2. Fig. 4 is a sectional view taken along line 4-4 in Fig. 1 showing an embodiment of a coating drying apparatus.
DESCRIPTION OF SYMBOLS 1 Coating dryer 2 Drying furnace 4 Far-infrared heater 10 Electrode terminal 15 Removal means

Claims (1)

In the drying furnace, in the coating drying apparatus having a heater for heating and drying the coating agent containing the flammable solvent applied on the base material by energizing through the electrode terminal,
The electrode terminal is disposed outside the drying furnace,
Provided outside the drying furnace in which the electrode terminal is disposed, a removing means for removing at least the gas of the coating agent flowing out from the drying furnace to the outside from the vicinity of the electrode terminal,
In the drying furnace, a lid that can be opened and closed with respect to the substrate on which the coating agent is applied, and a part of the upper wall that can be opened and closed, and a nonwoven fabric disposed in the lid, this nonwoven fabric and a water supply means for supplying water, provided the saturation holding means atmosphere is capable of holding the saturation in the furnace in contact with the coated surface of the substrate, wherein the coating agent is applied,
A drying apparatus for coating, characterized in that a blower for drying and solidifying by applying hot air to the coated surface of the substrate is provided in the drying furnace .

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