JP5086721B2 - Web heating and cooling apparatus and web heating and cooling method - Google Patents

Description

  The present invention relates to a web heating / cooling apparatus and a web heating / cooling method capable of heating and cooling a belt-like web conveyed at a predetermined speed to a predetermined temperature.

  In general, while a long web such as a belt-shaped plastic film, paper or cloth is conveyed at a constant speed, a predetermined coating film is continuously formed on the surface of the web. For example, an optical element such as a heat seal layer or an antireflection layer. The desired product with layers may be made. As such an apparatus, a conveying unit that conveys the web at a predetermined speed from a holding unit that winds the web in a roll shape, and a coating apparatus that forms a predetermined coating film on the web surface in the web conveyance path, There is known a heating means for drying and solidifying a coated film by heating and a winding means for winding and collecting the web in a roll (Patent Document 1).

  Here, for example, when a heat seal layer is formed on the web surface, it is necessary to heat the web to a temperature of about 100 ° C. and hold it for a predetermined time after applying a predetermined resin component, and to dry the coating film. When the web is heated and dried, the web itself is also heated to substantially the same temperature. If the web is wound up and collected immediately after drying, the web is wound up in a roll shape, and the heat seal layer is melted and the web is melted. The problem of adhering to the back surface (the surface where the heat seal layer is not formed) occurs. On the other hand, in the product in which the optical layer is formed, the web contracts in the width direction and the optical characteristics are deteriorated.

Such a problem can be solved by setting a longer conveying distance between the heating means and the winding means, or lowering the web conveying speed to increase the time until the web is wound. Such a configuration leads to a decrease in production efficiency due to an increase in the installation area of the apparatus and a decrease in the conveyance speed. For this reason, it is conceivable to provide a cooling means adjacent to the heating means on the downstream side of the heating means in the web conveyance path. As a simple cooling means, the direction perpendicular to the web conveyance direction is considered. The one which blows gas from is known (cited document 2).
JP 2000-84465 A JP 2003-4375 A

  However, when the cooling means as described above is provided adjacent to the heating means so as to reduce the installation area of the apparatus, a part of the gas blown toward the web flows out to the heating means side, and from the heating means. A region where the hot air and the cool air of the cooling means are mixed is generated. When this region occurs, the heating efficiency of the heating means is locally decreased, or the web is locally cooled after being heated by the heating means and then cooled by blowing a gas, Temperature unevenness occurs in the width direction of the web. As a result, the web cannot be heated or cooled substantially uniformly over its entire width, and a product having an optical layer has problems such as deterioration of optical characteristics.

  Accordingly, an object of the present invention is to provide a web heating / cooling apparatus and heating / cooling method capable of heating and cooling a web efficiently and uniformly with a small installation area in view of the above points.

In order to solve the above problems, the heating and cooling apparatus of the present invention includes a heating unit on the upstream side and a cooling unit on the downstream side adjacent to each other in the conveyance path of the web conveyed at a predetermined speed. A heating / cooling device for a web, wherein the cooling means includes a blowing nozzle that blows gas toward one or both sides of the web, and the blowing nozzle is formed on the web from a downstream direction of the web or a direction perpendicular to the web. It is close to the state, and are so bent as to direct the tip portion of the downstream side of the web, so as to face at least one of the upper and lower surfaces of the web, conveying the leading end portion of the blowout nozzle of the web It further includes a shielding plate extending toward at least the downstream side in the direction .

  It is desirable to set the width of the outlet of the blowing nozzle to be larger than the width of the web.

  Preferably, the heating means includes a heating furnace in which the web is conveyed and a heat source disposed in the heating furnace for heating the web by radiant heat.

Furthermore, in order to solve the above problems, the heating and cooling method of the present invention using the web heating and cooling apparatus heats the web to a predetermined temperature by radiant heat in the conveyance path while conveying the web at a predetermined speed. And a cooling step of cooling the web by blowing gas from the oblique direction upstream of the web conveyance direction on the downstream side.

  In the cooling step, the gas may be cooled to room temperature or lower in advance.

  On the other hand, you may make it cool the surrounding atmosphere which blows gas on the said web below room temperature.

According to the present invention, since the blowing nozzle is brought close to the web from the downstream side direction of the web or the direction perpendicular to the web, the distance between the upstream heating means can be reduced, The installation area can be reduced. Moreover, since the front-end | tip part of a blowing nozzle is bent so that it may face in the conveyance direction downstream of a web, gas can be sprayed on a web from the upstream diagonal direction of a conveyance direction, and a web can be rapidly cooled with high energy efficiency . During this cooling, most of the gas reflected by the web flows in the downstream direction, so even if the heating means and the cooling means are arranged adjacent to each other at a narrow interval, the hot air from the heating means and the cooling air from the cooling means Can be prevented from mixing with each other, and as a result, the web can be heated or cooled substantially uniformly over the entire width in the width direction. In addition, by providing a shielding plate that faces at least one of the upper surface and the lower surface of the web and extends from the tip of the blowing nozzle toward at least the downstream side in the web conveyance direction, it collides with the web surface and is reflected. The gas is re-reflected by the shielding plate and blown again to the web, so that the cooling efficiency of the web can be further increased.

  Further, if the width of the outlet of the blowing nozzle is set larger than the width of the web, it is possible to prevent the turbulent gas that is likely to be generated at both ends in the width direction of the nozzle outlet from being blown onto the web. As a result, only the gas in the laminar flow state in which the streamline direction is aligned is blown onto the web, and it is prevented that the hot air from the heating means and the cool air from the cooling means are mixed with each other. Cooling can be performed more uniformly over the entire width in the width direction.

  Further, if the heat source of the heating means is configured to heat the web by radiant heat, it is difficult for hot air to be transmitted to the cooling means, and it is possible to further prevent the hot air from the heating means and the cool air of the cooling means from being mixed.

  In FIG. 1, reference numeral 1 denotes a belt-shaped web heating / cooling device according to the present invention, and the heating / cooling device 1 is arranged in a conveyance path of the web R in a conveyance device 2 that conveys the web R at a predetermined speed. The conveying device 2 includes a feeding shaft 21 provided on the frame 20 and a winding shaft (winding means) 22, and the web R wound in a roll shape is held on the feeding shaft 21. The web R is made of a material appropriately selected from a synthetic resin film, paper, cloth, and the like according to the product to be manufactured.

  The web R fed out from the feed shaft 21 passes between the guide roller 23 and the pair of upper and lower pinch rollers 24a and 24b, is guided below the frame 20, and is then placed under the other frame 10 that supports the heating and cooling device. It is horizontally conveyed to the other side of the frame 10 by guide rollers 10a and 10b provided on the side. Then, it is directed upward in the perpendicular direction by a guide roller 31 provided on a frame 30 that supports a coating apparatus described later, and is guided to the coating apparatus 3. The coating apparatus 3 has a known structure and has a predetermined coating appropriately selected according to a backing roller 32 that conveys the web R and a layer to be formed on the surface of the web R, such as a heat seal layer or an antireflection layer. The die coater 33 forms a film with a constant film thickness. In addition, the coating apparatus 3 is not limited to this, A roll coat method, a blade coat method, a knife coat method, a gravure coat method etc. are implemented according to the coating film to form on the web R surface. A thing can be selected suitably.

  The web RL on which the predetermined coating film is formed is conveyed to the heating / cooling device 1 of the present invention while being horizontally conveyed. The heating means 1a of the heating / cooling device 1 supported by the frame 10 is a heating furnace 12 in which an inlet 12a and an outlet 12b are formed so that the web RL can be horizontally conveyed therein, and the circumference of the web RL has a certain length. I have something to enclose. Inside the heating furnace 12, heat sources 13 having a known structure composed of infrared lamps, halogen lamps, and the like are arranged at predetermined intervals along the longitudinal direction, and reach the outlet 12b from the inlet 12a of the heating furnace 12. In the meantime, the web RL is heated to a predetermined temperature range by radiant heat and held for a predetermined time. The length of the heating furnace 12 is appropriately set according to the heating temperature of the web RL and the heating efficiency of the heat source 13, and metal reflectors above and below the heat source 13 to efficiently heat the web RL. 14 is arranged. On the downstream side of the heating means 1a, a cooling means 1b is provided adjacent to the heating means 1a.

  As shown in FIG. 2, the cooling unit 1 b includes, for example, an airflow generating unit (not shown) such as a blower or a blower fan provided in the housing 15, a blower duct 16 connected to the airflow generating unit, The blowing nozzle 17 is connected to the tip of the duct 16, and the blowing nozzle 17 has a wall surface on the upstream side of the blowing nozzle 17 in the vertical direction, that is, parallel to the wall surface 12c of the heating furnace 12 in which the outlet 12b is formed. It forms so that it may become, and it adjoins so that it may crawl along the wall surface 12c.

  The tip of the blowing nozzle 17 that is tapered is bent so as to face the downstream side in the conveyance direction of the web RL, and the gas blown out from the blowing nozzle 17 enters the web RL from obliquely upstream above the conveyance direction of the web RL. It is configured to be sprayed. Further, the lateral width W1 of the blowout port 17a of the blowout nozzle 17 is wider than the full width W2 of the web RL (see FIG. 2B). For this reason, only the gas of the laminar flow state with which the streamline direction was equal can be sprayed on web RL. Usually, air is used as a gas to be blown, but an inert gas such as argon or nitrogen may be used depending on the type of coating film. Thereby, the blown-out gas collides with the web RL from obliquely upward on the upstream side in the transport direction, whereby the web can be rapidly cooled with high energy efficiency.

  In addition, a wind speed is suitably set according to the kind of coating film, and the cooling rate per unit time, for example, is set to 10 m / min or less in the case of a coating film which requires surface smoothness. The height h from the web RL to the outlet 17a is set so that when the gas is blown, the gas collides with the web RL with a sufficient air volume, and the collided gas flows downstream. Further, the tip of the blowing nozzle 17 is bent so that the incident angle α of the gas blown from the blowout port 17a to the web RL is 10 to 45 degrees, preferably 25 to 30 degrees (FIG. 2 ( a)). If the angle is smaller than 10 degrees, high cooling efficiency cannot be achieved. On the other hand, if the angle is larger than 45 degrees, gas may flow out to the heating furnace 12 side.

  By arranging the cooling means 1b blowing nozzle 17 along the wall surface 12c of the heating furnace 12 according to the above configuration, the interval between the heating means 1a and the cooling means 1b can be narrowed, and the installation area of the apparatus can be reduced. In addition, after exiting the outlet 12b of the heating furnace 12, the distance D to the position where the gas is collided to start cooling is shortened (see FIG. 2A), and the web RL is rapidly cooled immediately after heating. The During this cooling, most of the gas reflected by the web RL flows in the downstream direction. Therefore, even if the heating means 1a and the cooling means 1b are arranged adjacent to each other at a narrow interval, the gas is collided and cooled. It is possible to prevent the hot air from the heating unit 1a and the cold air from the cooling unit 1b from mixing on the upstream side of the position where the starting of the heat is started, and to prevent temperature unevenness from occurring in the heated or cooled web RL.

  Then, the web RL cooled to a predetermined temperature or lower by the cooling means 1b is rotated by a driving roller (not shown) by a motor via guide rollers 18a, 18b and 18c, and is rolled on the winding shaft 22. Wound and collected. In this case, a driving roller that is rotationally driven by a motor constitutes a conveying unit that conveys the web RL at a constant speed. The number and location of the driving rollers may be set as appropriate. For example, at least one of the above-described guide rollers may be a driving roller.

  Next, the formation of the coating film on the web R by the above apparatus will be described by taking a heat seal layer as an example. First, the web R wound in a roll shape is held on the feeding shaft 21 of the transport device, and then the leading end of the web R is fed out and hung around the guide roller 23. Then, the tip of the web R is passed between the pair of upper and lower pinch rollers 24 a and 24 b and is wound around the guide rollers 10 a, 10 b and 31 and the backing roller 32, and then passed through the heating furnace 12. The leading end of the web R coming out of the outlet 12b of the heating furnace 12 is fixed to the winding shaft 22 via the guide rollers 18a, 18b and 18c, and the setting of the web R is completed.

  Next, after operating the heat source 13 in the heating furnace 12 and the blower fan of the cooling means 1b, the motor is operated to rotate the drive roller. When the drive roller is rotationally driven, a feeding force is applied to the web R, and the web R is continuously conveyed at a predetermined speed. Then, a predetermined coating film is formed on the surface of the web R by the die coater 33 and guided to the heating furnace 12. For example, when forming a heat seal layer on the surface of the web R, after applying a predetermined resin component, the web RL is heated in a temperature range of about 100 ° C. in the heating furnace 12 and held for a predetermined time. Is formed.

  Next, the web RL exiting the heating furnace 12 is naturally cooled by being exposed to the atmosphere, and is conveyed to a position where gas is blown by the cooling means 1b. The gas is blown by the cooling means 1b and rapidly cooled below a predetermined temperature. . Even when a heat seal layer is formed on the surface of the web RL and the web RL is heated and dried at a temperature of about 100 ° C., heat is applied to the web RL when the web RL is wound around the take-up shaft 22 in a roll shape. It is rapidly cooled to a temperature at which the heat seal layer is not fused. When cooling the web RL by blowing the gas, the gas is cooled in advance to room temperature or lower (for example, a temperature in the range of room temperature to 10 ° C.), and the cooling efficiency is improved by blowing the cooled gas. Also good. Then, the web RL cooled to a predetermined temperature or lower is continuously wound in a roll shape on the winding shaft 22 and collected.

  In the present embodiment, the air flow generating means is described. However, the present invention is not limited to this, and the blow nozzle 17 is connected to a known compressor, and the compressed air is blown to the web RL. May be. Thereby, the air volume which collides with web RL increases by the air around the blowing nozzle 17 being accompanied by the compressed air injected from the blowing nozzle 17, and cooling efficiency may be able to be improved.

  In addition, as shown in FIG. 3, in order to increase the cooling efficiency of the web RL, the cooling means 1b may be disposed above and below the web RL (that is, configured to blow gas on both surfaces of the web RL). . Further, the shielding plates 4a and 4b extending from the tip of the blowing nozzle 17 to the upstream side and the downstream side in the conveyance direction of the web RL may be provided to face the upper surface and the lower surface of the web RL. The shielding plates 4a and 4b are set to a width wider than the width of the web RL. As a result, the gas reflected by the web RL is re-reflected by the shielding plate 4a and sprayed again on the web RL, so that the cooling efficiency of the web RL can be further increased. In this case, a refrigerant circulation system may be provided around the shielding plate 4a so that the space defined by the shielding plate 4a and the web RL has an atmosphere lower than room temperature. In FIG. 3, another shielding plate is provided that extends from the tip of the blowing nozzle 17 toward the upstream side in the conveyance direction of the web RL until it contacts the wall surface 12 c of the heating furnace 12. May be omitted.

  In the present embodiment, as the blowing nozzle 17, the upstream wall surface of the blowing nozzle 17 is formed in a straight line perpendicular to the web RL, and the other wall surface is inclined so as to be tapered. If the gas from the blowing nozzle 17 can be blown onto the web RL at the above angle, the form of the blowing nozzle 17 is not limited to this. As shown in FIG. 4, as the blowing nozzle 5a having another form, the wall surfaces on both sides are formed in a straight line perpendicular to the web RL, and only the tip is bent (see FIG. 4 (a)), Further, as the other blowing nozzles 5b and 5c, the wall surface on the upstream side of the blowing nozzle is curved or bent from the upstream side to the downstream side in the conveyance direction of the web RL, and only the lower surface thereof is formed substantially parallel to the web RL. The tip may be bent at a substantially right angle (see FIGS. 4B and 4C).

The figure explaining arrangement | positioning to the conveying apparatus of the heating-cooling apparatus of this invention. (A) And (b) is a principal part enlarged view explaining cooling of the web using the heating-cooling apparatus shown in FIG. The principal part enlarged view explaining the other modification of the heating-cooling apparatus shown in FIG. (A) And (b) is a figure explaining the other modification of a blowing nozzle.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Heating / cooling apparatus 1a Heating means 1b Cooling means 12 Heating furnace 13 Heat source 17 Outlet nozzle 17a Outlet 2 Conveying apparatus 4a, 4b Shielding board R, RL Web W1, W2 Width

Claims (6)

A heating and cooling apparatus for a web comprising a heating means on the upstream side and a cooling means on the downstream side thereof adjacent to each other in a web conveyance path conveyed at a predetermined speed,
The cooling means has a blow-out nozzle that blows gas toward one or both sides of the web, and the blow-off nozzle is brought close to the web from the downstream side of the web or from the direction perpendicular to the web, and the leading end thereof is web der those bent to direct downstream side of the is,
A web heating / cooling device , further comprising a shielding plate facing at least one of the upper surface and the lower surface of the web and extending toward at least the downstream side in the web conveyance direction from the tip of the blowing nozzle. . The balloon width of the air outlet of the nozzle, according to claim 1 Symbol mounting web, characterized in that set larger than the width of the web heating and cooling device. 3. The web heating / cooling according to claim 1, wherein the heating means includes a heating furnace in which the web is conveyed and a heat source disposed in the heating furnace to heat the web by radiant heat. apparatus. A web heating and cooling method using the web heating and cooling device according to claim 1,
While transporting the web at a predetermined speed, a heating step of heating the web to a predetermined temperature by radiant heat in the transport path, and cooling the web by blowing gas from the upstream oblique direction of the web transport direction on the downstream side The method of heating and cooling a web, comprising the step of: The method for heating and cooling a web according to claim 4, wherein the gas is cooled in advance to room temperature or lower. The method for heating and cooling a web according to claim 4 or 5, wherein an ambient atmosphere in which gas is blown to the web is cooled to room temperature or lower.

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