JP3207580B2 - Raw coating equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a raw material coating apparatus for forming a coating layer such as a magnetic layer on a sheet material.

[0002]

2. Description of the Related Art Heretofore, as a raw material coating apparatus, there has been known an apparatus having a coating section for applying a coating solution to a coating surface of a raw sheet and a drying section provided downstream of the coating section.

[0003] Of these, the coating section has a plurality of rolls, and the coating liquid is applied to the coating surface when the raw material passes between these rolls. For example, when a magnetic layer is formed, a magnetic powder, a resin, a solvent, and the like are mixed in a coating solution.

[0004] The raw material to which the coating liquid has been applied by the coating unit is then sent to a drying unit and dried by heating. In this case, the solvent in the coating solution is scattered outward, so that a magnetic layer is formed on the coated surface of the raw material. With respect to the drying section, there are known those that blow wind only on the coat surface and those that blow wind at the same temperature on both the upper and lower sides.

[0005]

As described above, the raw material to which the coating liquid has been applied in the coating part is sent to the drying part where it is heated and a coating layer such as a magnetic layer is formed on the raw material. .

In some cases, the raw material is rapidly heated in the drying section in order to increase the processing speed. In this case, the resin on the surface of the coating solution is dried before the solvent is scattered, and the coating is performed. The quality of the coat layer may be deteriorated by foaming due to the residual solvent inside the layer.

[0007] The present invention has been made in view of the above points, and an object of the present invention is to provide a raw material coating apparatus capable of increasing the speed of a coating process and improving the quality of a coat layer. Aim.

[0008]

According to the present invention, there is provided a coating section for applying a coating solution to a coating surface of a sheet-like raw material, and a drying section provided on a downstream side of the coating section. It has a plurality of hot air blowing nozzles arranged continuously on both sides of the raw material, and the hot air blowing nozzle on the non-coated surface side of the raw material has a higher temperature than the hot air blowing nozzle on the nearby coated surface side. This is a raw material coating apparatus characterized by blowing hot air.

[0009]

The raw material having the coating liquid applied to the coating surface by the coating unit is sent to the drying unit and dried by heating. The hot-air blowing nozzle on the non-coated side of the raw material blows out hot air from the nearby hot-air blowing nozzle on the coated side, so the solvent inside the coating liquid is removed before the coating liquid surface dries. Can be scattered.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 are views showing an embodiment of a raw material coating apparatus according to the present invention.

First, an example of a coated product such as a magnetic raw material manufactured by a raw material coating apparatus will be described with reference to FIG. As shown in FIG. 2, the coating product 40 has a synthetic resin layer 42 such as polyethylene terephthalate, for example, and a relatively thick magnetic layer 43 formed on the lower surface of the synthetic resin layer.

In the raw material coating apparatus according to the present invention, the magnetic layer 43 is formed on the raw material 30.

In FIG. 1, the raw material coating apparatus is
The sheet is fed to a sheet feeding section 11 for supplying a sheet-like raw material 30 made of a synthetic resin such as polyethylene terephthalate, and a coating apparatus 14 provided downstream of the sheet feeding section 11.

The drying section 20 is of a floating dryer type comprising a first zone 21, a second zone 22, a third zone 23 and a fourth zone 24, and heats from the first zone 21 to the fourth zone 24. The temperature gradually rises.

The drying section 20 will be described with reference to FIG. The drying unit 20 includes the first to fourth zones 21 to 24 as described above.
Hot air blowing nozzles 31 continuously arranged above the
And a plurality of hot air blowing nozzles 32 continuously arranged below the raw fabric 30. These hot air blowing nozzles 3
The reference numerals 1 and 32 blow out the hot air to the web 30 and dry it, and hold the web 30 in a non-contact state.

The lower side (non-coated side) of the web 30
The hot air blowing nozzle 32 blows out hot air at a higher temperature than the hot air blowing nozzle 31 on the upper side (coat surface side) in the vicinity. Further, the hot air blowing nozzle 32 on the lower side of the raw fabric 30 is configured to emit warm air that gradually increases in temperature from the first zone 21 toward the fourth zone 24. The hot air blowing nozzle 31 on the upper side also blows out hot air that gradually increases in temperature from the first zone 21 to the fourth zone 24.

Next, the operation of this embodiment having the above configuration will be described.

First, a case in which a thick magnetic layer 43 is formed on the surface of a synthetic resin raw material 30 such as polyethylene terephthalate will be described. Material 3 supplied from the paper feeding unit 11
0 is sent to the thick film coating device 14, and the coating solution is applied to the coating surface of the raw material 30 by the thick film coating device 14.

In this case, the coating liquid contains a magnetic powder, a resin, and a solvent.

Subsequently, the raw material 30 is sent to the heating roll 16, and the non-coated surface side of the raw material 30 is heated by the heating roll 16. As described above, when the raw fabric 30 is heated from the non-coated surface side, the solvent in the coating liquid is gradually scattered outward.

Next, the raw fabric 30 is dried by heating. That is, the raw fabric 30 is heated and dried from the first zone 21 to the fourth zone 24 with warm air that gradually increases in temperature. Similarly, the raw fabric 30 is heated at the same position by the hot-air blowing nozzles 31 and 32 so that the non-coated surface has a high temperature.
Since the uncoated surface is heated to a high temperature in this manner, the solvent in the coating liquid can be scattered outward before the coating liquid surface dries, and the magnetic layer 43 having excellent quality can be obtained.
Can be obtained.

That is, the heating speed is increased to increase the
Is dried, the surface of the coating solution is dried first to form a film, and the residual solvent foams in the magnetic layer 43.

However, when the raw fabric 30 is heated so that the uncoated surface side is higher in temperature than the coated surface side as in the present invention, even if the heating speed is increased (even if the processing speed is increased), The solvent can be scattered outward without forming a film on the surface. Therefore, foaming of the residual solvent in the magnetic layer 43 can be prevented, and the quality can be improved.

[0024]

As described above, according to the present invention, the solvent in the coating solution can be scattered to the outside before forming a film on the surface of the coating solution. Therefore, foaming of the residual solvent inside the coat layer can be prevented, and a high-quality coat layer can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic system diagram showing an embodiment of a raw material coating apparatus according to the present invention.

FIG. 2 is a side sectional view showing a coated product.

FIG. 3 is an enlarged side view showing a hot air blowing nozzle of a drying unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Raw material coating apparatus 14 Thick film coating part 20 Drying part 30 Raw material 31 Hot air blowing nozzle 32 Hot air blowing nozzle

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Ayumi Yoshida 1-1-1 Ichigaya-Kagacho, Shinjuku-ku, Tokyo Inside Dai Nippon Printing Co., Ltd. (72) Inventor Hideki Inada Ichigaya Kaga, Shinjuku-ku, Tokyo 1-1-1, Machida Dai Nippon Printing Co., Ltd. (56) References JP-A-57-99373 (JP, A) JP-A-60-42585 (JP, A) (58) Fields investigated (Int. . ^7, DB name) B05C 9/14 B05C 1/08 B05D 3/00 - 3/14 G11B 5/842 F26B 21/00 - 21/12

Claims (1)

(57) [Claims] 1. A coating section for applying a coating solution to a coating surface of a sheet-like raw material, and a drying section provided downstream of the coating section, wherein the drying sections are provided on both sides of the raw material. It has a hot air blowing nozzle continuously disposed, and the hot air blowing nozzle on the non-coated surface side of the raw material blows out hot air at a higher temperature than the hot air blowing nozzle on the nearby coated surface side. Characteristic raw material coating equipment.