JP2000035279A - Drying equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve adhesion to a base of a paint film in printing and coating. SOLUTION: An infrared-ray drying furnace 4 or a heat roll 8 is used. Further, a warm air furnace 10 which is inexpensive in terms of an equipment is juxtaposed for reducing residual solvents. Undried coating liquid causes convection in a paint film without causing skinning of the paint film, so that adhesion to a base of the paint film is improved because the solvent flies out itself externally.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a drying apparatus used for printing and coating various industrial materials.

[0002]

2. Description of the Related Art Generally, in printing and coating,
It is very important to improve the adhesion of the coating film formed on the substrate to the substrate, in order to improve the function of the product.
Hot air drying is mainly used as the drying method in printing and coating.However, in this method, the composition becomes uneven on the surface of the coating film and inside the coating film, and this may cause poor adhesion. I know it. Therefore, drying is performed under mild conditions (for example, at a temperature of 50 ° C. and a wind speed of 5 m / s) in order to increase the adhesion of the coating film to the substrate. Further, in the latter half of the drying in which the adhesion is determined, in order to reduce the residual solvent, high temperature and high wind speed (for example, temperature 140
Drying at a temperature of 30 ° C. and a wind speed of 30 m / s).

[0003]

However, even when hot air drying is performed under mild conditions, the composition in the coating film is somewhat uneven, and the thicker the film, the more sufficient the adhesion to the substrate. There is a problem that cannot be obtained.

[0004] The present invention has been made in view of the above-mentioned problems.
It is an object of the present invention to provide a drying apparatus which can improve the adhesion between a substrate and a coating film and can perform highly efficient drying.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention relates to a heating apparatus which does not cause swelling of a coating film and which causes convection of an undried coating liquid in the coating film. We will use means. Then, by heating and drying the coating film by such a heating means, the solvent in the coating liquid spurts out naturally, and the adhesion of the coating film to the substrate can be improved.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention uses an infrared drying oven for heating and drying by passing an applied substrate in order to improve the adhesion of a coating film to the substrate in printing and coating. .

Further, in the present invention, in order to improve the adhesion of the coating film to the substrate in printing and coating, a heated roll is used in which the coated substrate is brought into close contact with the back surface and heated and dried.

In the present invention, the infrared drying oven and the heat roll are arranged in front and rear. The order is not particularly limited, but the order of the infrared drying oven and the hot roll is preferred from the viewpoint of easy temperature control of the coating film and the substrate.

Further, in the present invention, a hot air drying furnace is arranged immediately after the infrared drying furnace. In the infrared drying oven, although the adhesion of the coating film to the substrate is improved, the heat transfer coefficient is small and the drying efficiency is low compared to the ordinary hot air drying method, and the equipment is expensive. However, it is not easy to control the temperature of the substrate. Therefore, in the infrared drying oven alone, it takes time to reduce the residual solvent after determining the adhesion,
Since the drying efficiency is reduced, it is preferable to provide a low-cost hot-air drying furnace having relatively good heat transfer efficiency.

In the present invention, a hot-air drying oven is arranged immediately after the hot roll. In the drying of the heat roll,
Although the adhesion of the coating film to the substrate is improved, the heat transfer coefficient is large and the drying efficiency is good compared to the normal hot air drying method, but drying for a long time is limited because the roll diameter is limited in equipment. No, and the equipment is expensive. Therefore, it is not possible to dry only the hot rolls until the residual solvent is reduced after the determination of the adhesion, and therefore it is preferable to provide a hot air drying roll that is inexpensive in terms of equipment.

Further, in the present invention, a hot air drying furnace is arranged immediately after the infrared drying furnace and the heat roll are arranged in front and rear. The order of the infrared drying oven and the hot roll may be either order, but the order of the infrared drying oven and the hot roll is preferable in that the temperature control of the coating film and the substrate is easy.

[0012]

Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 shows the structure of an infrared drying oven. As shown in the drawing, the infrared drying furnace 4 is provided with a carry-in port 2a and a carry-out port 2b at both ends in the longitudinal direction, respectively, so that the base material 1 passes from the carry-in port 2a toward the carry-out port 2b. Has become. A guide roll 3 for supporting the substrate 1 and an infrared panel heater 5 are provided in the infrared drying furnace 4. Infrared panel heater 5
As a heating method, for example, a method in which electricity is used for a water-based ink, and a method in which oil or steam is used as a heating medium for an organic solvent-based ink is used. In addition, air supply port 6 and exhaust port 7
Is provided for controlling the ambient temperature and the solvent concentration in the infrared drying furnace 4, and is not used for drying the coating film by directly blowing hot air on the coating film.
Further, in order to prevent the surface temperature distribution of the infrared panel heater 5, the wind is not applied to the infrared panel heater 5. In the infrared drying furnace of this embodiment, the coating film is dried by the infrared panel heater 5 without directly blowing hot air to determine the adhesion between the substrate 1 and the coating film.

FIG. 2 shows a hot roll. As shown in the figure, the heat roll 8 heats the base material 1 immediately after application from the lower surface. As a heating medium of the heating roll 8, electricity, heating medium oil, or the like is used.

In the embodiment shown in FIG. 3, a heat roll 8 shown in FIG. 2 is provided immediately before the infrared drying furnace 4 shown in FIG. In this drying device, the coated base material is first heated from below by a hot roll 8, and immediately thereafter passes through an infrared drying oven 4. Conversely, a heat roll 8 may be provided immediately after the infrared drying furnace 4.

In the embodiment shown in FIG. 4, a hot air drying furnace 9 is provided immediately after the infrared drying furnace 4 shown in FIG. In this drying device, after the adhesion between the substrate 1 and the coating film is determined in the infrared drying furnace 4, the residual solvent is reduced to a specified amount by the hot air from the hot air nozzle 10 in the hot air drying furnace 9. Drying is carried out.

In the embodiment shown in FIG. 5, a hot air drying furnace 9 is provided immediately after the hot roll 8 shown in FIG. In this drying device, after the adhesiveness between the base material 1 and the coating film is determined by the hot roll 8, the residual solvent is reduced to a specified amount by the hot air from the hot air nozzle 10 in the hot air drying furnace 9. Drying is performed.

In the embodiment shown in FIG. 6, the infrared drying furnace 4 shown in FIG. 1 is provided immediately after the hot roll 8 shown in FIG. 2, and a hot air drying furnace 9 is provided immediately after the infrared drying furnace 4. ing. Conversely, a hot roll 8 may be provided immediately after the infrared drying furnace 4 and a hot air drying furnace 9 may be provided immediately after the hot roll 8.

Table 1 shows the test results on the adhesion between the substrate and the coating film by various drying methods. A polyester film is used as a base material, on which ink (pigment: 25% by weight, binder: 25% by weight, solvent: 50%)
(% By weight) to form a coating film having a thickness of 120 μm (dry), which was dried by the drying method shown in Table 1.

[0020]

[Table 1]

From Table 1, it can be seen that the adhesion between the substrate and the coating film is improved in the order of a normal hot air drying system, an infrared drying system, and a hot roll drying + infrared drying system.

[0022]

As described above, the use of the drying apparatus of the present invention improves the adhesion between the substrate and the coating film as compared with the hot air drying method which is frequently used as the drying method. be able to.

In addition to using an infrared drying oven or a heating roll alone, rather than using hot air drying, by combining them, the adhesion between the base material and the coating film is improved and high-efficiency drying is performed. be able to.

[Brief description of the drawings]

FIG. 1 is a structural view of an infrared drying oven.

FIG. 2 is a structural diagram of a hot roll.

FIG. 3 is a structural view of a drying apparatus provided with a heat roll immediately before an infrared drying oven.

FIG. 4 is a structural view of a drying apparatus provided with a hot air drying furnace immediately after an infrared drying furnace.

FIG. 5 is a structural view of a drying apparatus provided with a hot air drying furnace immediately after a hot roll.

FIG. 6 is a structural view of a drying apparatus provided with an infrared drying oven immediately after a hot roll.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 base material 2a carry-in 2b carry-out 3 guide roll 4 infrared drying oven 5 infrared panel heater 6 air supply port 7 exhaust port 8 heat roll 9 hot air drying oven 10 hot air nozzle

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Nobuyuki Tominaga 1-1-1, Ichigaya-Kagacho, Shinjuku-ku, Tokyo Inside Dai Nippon Printing Co., Ltd. (72) Inventor Minoru Ariyama 1-chome, Ichigaya-cho, Shinjuku-ku, Tokyo No. 1-1 F-term in Dai Nippon Printing Co., Ltd. (reference) 2C020 CA01 CA03 CA05 CA06 3L113 AB02 AC10 AC32 AC45 AC46 AC48 AC52 AC54 AC63 AC64 BA26 BA30 BA32 DA02 DA06 DA18 DA24

Claims (6)

[Claims] 1. A drying apparatus characterized by using an infrared drying furnace that heats and dries a coated substrate in order to improve the adhesion of the coating film to the substrate in printing and coating. 2. A drying apparatus characterized by using a heat roll that heats and dries a coated substrate from its back surface in order to improve the adhesion of the coating film to the substrate in printing and coating. 3. In order to improve the adhesion of a coating film to a substrate in printing and coating, an infrared drying furnace for heating and drying the coated substrate by passing the coated substrate, and bringing the coated substrate into close contact with the back surface. A drying device, wherein a heating roll for heating and drying is arranged back and forth. 4. In order to improve the adhesion of a coating film to a substrate in printing and coating, an infrared drying oven for heating and drying by passing an applied substrate, and a hot air drying oven immediately after that are arranged. A drying device characterized by the above-mentioned. 5. In order to improve the adhesion of a coating film to a substrate in printing and coating, a heated roll for heating and drying the applied substrate by adhering it from the back surface, and a hot-air drying furnace immediately after that, are arranged. A drying device, comprising: 6. In order to improve the adhesion of a coating film to a substrate in printing and coating, an infrared drying furnace for heating and drying the coated substrate by passing the coated substrate, and the coated substrate being adhered from the back surface. A drying apparatus, wherein a hot-air drying furnace is arranged immediately after a heating roll for heating and drying is arranged in front and behind.