JP3897456B2 - Drying equipment - Google Patents

Description

【００２１】
この表１から、通常の温風乾燥方式、赤外線乾燥方式、熱ロール乾燥＋赤外線乾燥方式の順に基材と塗膜との密着性が向上していることが分かる。
【００２２】
【発明の効果】
以上説明したように、本発明の乾燥装置を使用すれば、塗膜に皮ばりを生じることなく、かつ塗膜内にて未乾燥の塗布液が対流を起こすような加熱手段を利用することになるため、このような加熱手段により塗膜を加熱、乾燥させることによって、塗布液中の溶剤が自然に外へ飛び出ることとなり、乾燥方式として頻繁に使われている温風乾燥方式に比べて、基材と塗膜との密着性を向上させることができる。
【００２３】
また、赤外線乾燥炉や熱ロールの単体での使用ではなく、温風乾燥を含め、それぞれを組み合わせることで、基材と塗膜との密着性を向上させ且つ高効率な乾燥を行うことができる。
【図面の簡単な説明】
【図１】 赤外線乾燥炉の構造図である。
【図２】 赤外線乾燥炉の直前に熱ロールを設けた乾燥装置の構造図である。
【図３】 赤外線乾燥炉の直後に温風乾燥炉を設けた乾燥装置の構造図である。
【図４】 熱ロールの直後に赤外線乾燥炉を設けた乾燥装置の構造図である。
【符号の説明】
１ 基材
２ａ 搬入口
２ｂ 搬出口
３ ガイドロール
４ 赤外線乾燥炉
５ 赤外線パネルヒータ
６ 給気口
７ 排気口
８ 熱ロール
９ 温風乾燥炉
１０ 温風ノズル[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a drying apparatus used for printing and coating various industrial materials.
[0002]
[Prior art]
In general, in printing and coating, it is very important to improve the adhesion of a coating film formed on a substrate to the substrate in order to improve the function of the product. As a drying method in this printing and coating, warm air drying is mainly used. However, in this method, composition non-uniformity occurs on the surface of the coating film and inside the coating film, which may cause poor adhesion. I know it. Therefore, drying is performed under mild conditions (for example, a temperature of 50 ° C. and a wind speed of 5 m / s) in order to improve the adhesion of the coating film to the substrate. In the second half of drying after the adhesion is determined, drying is performed at a high temperature and a high wind speed (for example, a temperature of 140 ° C. and a wind speed of 30 m / s) in order to reduce the residual solvent.
[0003]
[Problems to be solved by the invention]
However, even when warm-air drying is performed under mild conditions, there is some unevenness in the composition in the coating film, and as the film thickness increases, sufficient adhesion to the substrate cannot be obtained. There is.
[0004]
The present invention has been made in view of the above-described problems, and an object of the present invention is to improve the adhesion between the base material and the coating film and to perform highly efficient drying. Is to provide.
[0005]
[Means for Solving the Problems]
The drying apparatus according to claim 1 uses an infrared drying furnace that passes a coated substrate and heats and dries to improve the adhesion of the coating film to the substrate in printing and coating. In the infrared drying furnace, a guide roll and an infrared heater are installed in the infrared drying furnace, and the ambient temperature in the infrared drying furnace is such that the coating film and the infrared heater are not directly exposed to wind. and the air supply and exhaust system for controlling the solvent concentration is characterized that you have provided.
[0008]
Claims an invention according to claim 2 drying apparatus, the drying apparatus according to claim 1, the coated substrate to heat in close contact from the back, SEQ heat roll drying after just before or straight infrared drying furnace it was that features a.
[0009]
Invention is a drying apparatus according to claim 3, in the drying apparatus according to claim 1, it is characterized by an array of hot-air drying oven immediately after the infrared drying furnace.
[0010]
A drying apparatus according to a fourth aspect of the invention is the drying apparatus according to the first aspect, wherein a heating roll for heating and drying the coated substrate in close contact with the back surface is arranged immediately before the infrared drying furnace, that an array of hot-air drying oven immediately after the infrared drying furnace that features a.
[0011]
The drying apparatus according to claim 5 is the drying apparatus according to claim 1, wherein a heating roll for heating and drying the coated substrate from the back side is arranged immediately after the infrared drying furnace. that it is characterized by an array of hot-air drying oven immediately after the heat roll.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described with reference to the drawings.
[0013]
FIG. 1 shows the structure of an infrared drying furnace. As shown in the figure, 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 so that the base material 1 passes from the carry-in port 2a toward the carry-out port 2b. It has become. And in the infrared drying furnace 4, the guide roll 3 and the infrared panel heater 5 which support the base material 1 are installed. As a heating method of the infrared panel heater 5, for example, a method using electricity in the case of water-based ink and a method using oil steam as a heating medium in the case of organic solvent-based ink is used. An air supply port 6 and an exhaust port 7 are provided for controlling the atmospheric temperature and the solvent concentration in the infrared drying furnace 4, and spraying warm air directly on the coating film to dry the coating film. Not for use. Further, in order to prevent the surface temperature distribution of the infrared panel heater 5, the infrared panel heater 5 is prevented from being exposed to wind. The infrared drying furnace of the present embodiment determines the adhesion between the substrate 1 and the coating film by drying with the infrared panel heater 5 without blowing hot air directly on the coating film.
[0015]
In the embodiment shown in FIG. 2 , a heat roll 8 is provided immediately before the infrared drying furnace 4 shown in FIG. The heat roll 8 heats the substrate 1 immediately after coating from the lower surface, and electricity, heat medium oil, or the like is used as a heating medium for the heat roll 8. In this drying apparatus, the coated base material is first heated from the lower surface by the hot roll 8, and immediately thereafter passes through the infrared drying furnace 4. Conversely, a hot roll 8 may be provided immediately after the infrared drying furnace 4. The order may be either, but the order of the infrared drying furnace-heat roll is preferable in terms of easy temperature control of the coating film and the substrate.
[0016]
In the embodiment shown in FIG. 3 , a hot air drying furnace 9 is provided immediately after the infrared drying furnace 4 shown in FIG. In this drying apparatus, 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 warm air from the warm air nozzle 10 in the warm air drying furnace 9. Drying is performed. In the infrared drying furnace, the adhesion of the coating film to the substrate is improved, but compared to the normal hot air drying method, the heat transfer coefficient is small and the drying efficiency is poor, and the equipment is expensive, and the coating film The temperature control of the substrate is not easy. Therefore, in the infrared drying furnace alone, it takes time to reduce the residual solvent after determining the adhesion, and the drying efficiency is lowered. Therefore, a hot air drying furnace having a relatively good heat transfer efficiency and a low cost is provided. Is preferred.
[0018]
In the embodiment shown in FIG. 4 , the infrared drying furnace 4 shown in FIG. 1 is provided immediately after the hot roll 8, and the hot air drying furnace 9 is provided immediately after the infrared drying furnace 4. 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. The order of the infrared drying furnace and the heat roll may be either, but the order of the infrared drying furnace and the heat roll is preferable because the temperature control of the coating film and the substrate is easy.
[0019]
Table 1 shows the test results regarding the adhesion between the substrate and the coating film by various drying methods. A polyester film is used as a base material, and a 120 μm (dry) coating film is formed thereon with ink (pigment: 25 wt%, binder: 25 wt%, solvent: 50 wt%). It was dried by the drying method shown in 1.
[0020]
[Table 1]

[0021]
From Table 1, it can be seen that the adhesion between the base material and the coating film is improved in the order of the normal warm air drying method, infrared drying method, hot roll drying + infrared drying method.
[0022]
【The invention's effect】
As described above, when the drying apparatus of the present invention is used, a heating means that causes convection of an undried coating solution in the coating film without causing a coating on the coating film is used. Therefore, by heating and drying the coating film with such heating means, the solvent in the coating solution will naturally jump out , compared to the hot air drying method that is frequently used as a drying method, The adhesion between the substrate and the coating film can be improved.
[0023]
Moreover, it is possible to improve the adhesion between the base material and the coating film and perform highly efficient drying by combining each of them, including warm air drying, instead of using an infrared drying furnace or a heat roll alone. .
[Brief description of the drawings]
FIG. 1 is a structural diagram of an infrared drying furnace.
FIG. 2 is a structural diagram of a drying apparatus provided with a heat roll immediately before the infrared drying furnace.
FIG. 3 is a structural diagram of a drying apparatus provided with a hot air drying furnace immediately after an infrared drying furnace.
FIG. 4 is a structural diagram of a drying apparatus provided with an infrared drying furnace immediately after a hot roll.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Base material 2a Carry-in port 2b Carry-out port 3 Guide roll 4 Infrared drying furnace 5 Infrared panel heater 6 Air supply port 7 Exhaust port 8 Hot roll 9 Hot air drying furnace 10 Hot air nozzle

Claims (5)

In order to improve the adhesion of the coating film to the substrate in printing and coating, it is a drying apparatus using an infrared drying furnace that passes the coated substrate and heats and dries it. An air supply / exhaust system is installed to control the atmospheric temperature and solvent concentration in the infrared drying furnace so that the guide roll and infrared heater supporting the substrate are installed, and the coating film and infrared heater are not directly exposed to wind. Is provided with a drying apparatus. Heated in close contact with the coated fabric already substrate from the rear surface, the drying apparatus according to claim 1, characterized in that an array of hot roll drying after just before or straight infrared drying furnace. Drying apparatus according to claim 1, characterized in that an array of hot-air drying oven immediately after infrared drying furnace. Heated in close contact with the coated fabric already substrate from the back side, a heat roll drying to claim 1 which is arranged immediately before the infrared drying furnace, characterized by further arranged a hot air drying oven immediately after the infrared drying furnace The drying apparatus as described . The hot roll which heats and dries the coated substrate in close contact with the back surface is arranged immediately after the infrared drying furnace, and the hot air drying furnace is arranged immediately after the hot roll. Drying equipment.

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