JP2009174819A - Drying device and drying method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drying device for quickly drying a thin coating applied to a film while keeping the finishing accuracy of the thin coating high, and to provide a drying method. <P>SOLUTION: The drying device 4 is provided for drying the thin coating applied to one face 1 of the film 3 having one face 1 and the other face 2 and traveling in the direction of arrowmarks T1-T2. It comprises a preheating roller 5 for contacting the other face 2 of the film 3, a drying roller 6 for contacting the other face 2 of the film 3, a firing roller 7 for contacting one face 1 of the film 3, a heat removing roller 8 for contacting the other face 2 of the film 3, and a heating means for individually heating the four rollers 5-8. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a drying apparatus and a drying method for conducting and drying a thin film applied to a flexible film.

Conventionally, conductive lines are formed on a film by printing a conductive ink on a film using a screen printing apparatus, and then drying and solidifying a thin film made of the conductive ink. As an example of the conductive ink, there is a conductive paste formed by kneading a powdery silver or the like in a solvent together with a binder or the like. Techniques for drying the conductive ink include conductive drying, convection hot air drying, and radiation drying by infrared radiation heat transfer.
JP 2007-216391 A Japanese Patent Laid-Open No. 06-167796

  For example, when manufacturing an electronic component such as a plasma display, it is required to finish a conductive line formed on a film to a line width of about 20 μm. In order to achieve such a high dimensional accuracy, in the process of drying the conductive ink, the film is supported by a heat roller in order to suppress the distortion of the conductive wire due to the slackness of the film. It is desirable to conduct and dry the conductive ink.

  However, in order to dry the conductive ink well, it is necessary to heat the conductive ink to a high temperature of 200 ° C. For this reason, when a film expand | swells rapidly, wrinkles generate | occur | produce in a film and the precision of a conductive wire is impaired. Moreover, if the temperature rise of the conductive ink is moderated in order to avoid rapid expansion of the film, there arises a problem that the electric resistance of the conductive wire is remarkably increased. Further, the film heated to a high temperature as described above radiates heat until it returns to normal temperature. During this time, the film shrinks rapidly, so that wrinkles are generated in the film and the accuracy of the conductive wire is impaired.

  Accordingly, an object of the present invention is to provide a drying apparatus and a drying method capable of quickly drying a thin film applied to a film and maintaining a high finishing accuracy of the thin film.

  A drying apparatus according to the present invention is a device for running a film having a surface and another surface and drying a thin film applied to one surface of the film, the drying roller being in contact with the other surface of the film, and the film A baking roller in contact with one surface of the film, a heat removal roller in contact with the other surface of the film, and heating means for individually heating these rollers, and in order according to the travel of the film, the drying roller and the baking A roller and a heat removal roller are disposed, and the heating means heats the firing roller to the highest temperature among the drying roller, the firing roller, and the heat removal roller.

  A drying device according to the present invention is a drying device that travels a film having one surface and another surface, and dries a thin film applied to one surface of the film, the preheating roller being in contact with the other surface of the film, A drying roller in contact with the other surface of the film, a baking roller in contact with one surface of the film, a heat removal roller in contact with the other surface of the film, and heating means for individually heating these rollers, The preheating roller, the drying roller, the baking roller, and the heat removal roller are arranged in the order according to the travel of the film, and the heating means sets the temperature of the preheating roller, the heat removal roller, the drying roller, and the baking roller in that order. It heats so that it may become high.

  Furthermore, the drying apparatus according to the present invention is characterized in that the drying roller and the baking roller separate a gap of 50 mm or less. Furthermore, the drying apparatus according to the present invention is characterized in that the baking roller and the heat removal roller separate a gap of 50 mm or less.

  The drying method according to the present invention is to run a film having one surface and the other surface, and dry the thin film applied to the one surface of the film, and transfer the heat to the other surface of the film to heat the thin film. From the drying step, the baking step of transferring heat to one surface of the film and heating the thin film to a temperature higher than that of the drying step, and the film heated in the baking step, the temperature lower than the film heated in the baking step And a heat removal step of transferring heat toward the medium.

  The drying method according to the present invention is to run a film having one side and the other side, and to dry a thin film applied to one side of the film, contacting a drying roller to the other side of the film, and A drying process for transferring heat to the thin film by heating a roller, and a baking for transferring heat to the thin film by bringing the baking roller into contact with one surface of the film and heating the baking roller to a temperature higher than that of the drying roller. And a heat removal step of transferring heat from the film heated in the baking step to a medium having a temperature lower than that of the film heated in the baking step.

  According to the drying apparatus of the present invention, the temperature of the film can be increased stepwise in the process in which the film sequentially contacts the drying roller and the baking roller. For this reason, compared with the case where a film is raised from normal temperature to the temperature of a baking roller by one heat transfer, the rapid expansion | swelling of a film can be suppressed. Even if thermal stress is generated in the film, the film is supported by the drying roller or the baking roller, so that the shape of the film does not become distorted and wrinkles are not generated in the film.

  Moreover, when the film heated by the baking roller comes into contact with the heat removal roller, the heat removal roller acts as a medium for releasing the heat accumulated in the film and the thin film. As a result, the film is cooled by the heat removal roller and further dissipated from the heat removal roller until it reaches room temperature, so the temperature of the film drops stepwise. For this reason, rapid shrinkage of the film can be suppressed as compared with the case where the cooling of the film heated by the baking roller is dependent only on heat radiation to the atmosphere. Even if thermal stress is generated on the film, the film is supported by the heat removal roller, so that the shape of the film is not distorted and wrinkles are not generated on the film.

  Therefore, according to the drying apparatus, as described above, wrinkles are not generated in the film, and thus, when manufacturing electronic parts such as a plasma display, for example, conductive lines with high dimensional accuracy can be formed on the film. In addition, since a thin film made of conductive ink can be dried quickly, a conductive wire having an extremely low electric resistance can be formed. The effects described above can be achieved by the drying method according to the present invention.

  In addition, according to the drying apparatus of the present invention, the temperature of the film can be raised stepwise to the temperature of the baking roller in the process of sequentially contacting the film with the preheating roller, the drying roller, and the baking roller. Thereby, rapid expansion of the film can be suppressed. Even if thermal stress occurs in the film, since the film is supported by the preheating roller, the drying roller, or the baking roller, the shape of the film is not distorted, and the above effect can be achieved.

  Furthermore, according to the drying apparatus of the present invention, the gap between the drying roller and the firing roller is set to 50 mm or less, so that the film that crosses this gap is strongly subjected to the radiant heat of the firing roller before reaching the firing roller. And heated to a temperature higher than that of the drying roller. For this reason, since the rapid expansion of the film can be suppressed as compared with the case where the film is immediately heated to the temperature of the drying roller when it comes into contact with the baking roller, the effect of preventing wrinkling of the film becomes more remarkable.

  Furthermore, according to the drying apparatus according to the present invention, the gap between the firing roller and the heat removal roller is set to 50 mm or less, and the film that crosses this gap is strongly radiated by the firing roller, so the film is fired. The temperature drop due to the heat radiation of the film to the atmosphere can be suppressed before leaving the roller and reaching the heat removal roller. For this reason, the effect which prevents the wrinkle of a film becomes further remarkable.

  1 and 2 show a drying device 4 that travels a film 3 having one surface 1 and another surface 2 in a direction indicated by arrows T1 to T2 and dries a thin film applied to one surface 1 of the film 3. The drying device 4 includes a preheating roller 5 in contact with the other surface 2 of the film 3, a drying roller 6 in contact with the other surface 2 of the film 3, a baking roller 7 in contact with one surface 1 of the film 3, and other films 3. A heat removal roller 8 that contacts the surface 2 and a heating means 9 that individually heats the four rollers 5 to 8 are provided.

  The four rollers 5 to 8 are arranged in the order according to the travel of the film 3. The heating means 9 is obtained by connecting a temperature control device 91 to four electric heaters respectively housed in four rollers 5 to 8. The temperature controller 91 can individually set the currents supplied to the four electric heaters so that the temperatures of the preheating roller 5, the heat removal roller 8, the drying roller 6, and the baking roller 7 increase in this order. It ’s fine.

  The preheating roller 5 is mainly composed of a drum having a mirror surface around its circumference, and both ends of the preheating roller 5 are supported by a housing not shown in the drawing. The drying roller 6 and the heat removal roller 8 are configured in the same manner as the preheating roller 5. The firing roller 7 is configured in the same manner as the preheating roller 5 except that it is supported by the support means 10. The support means 10 guides the slider 12 with a guide frame 11 standing at an angle of about 45 ° with respect to the horizontal plane, supports the firing roller 7 with the slider 12, and follows the expansion and contraction of the piston rod 14 of the air cylinder 13. The firing roller 7 is moved up and down together with the slider 12.

  FIG. 2 shows one support means 10, but both ends of the baking roller 7 are supported by the respective sliders 12 of the two support means 10. The width of the gap 18 between the peripheral surface of the drying roller 6 and the peripheral surface of the baking roller 7 can be adjusted by the support means 10 moving the slider 12 up and down. The height of the slider 12 may be defined by a stopper or the like provided on the guide frame 11. Or you may raise / lower the slider 12 with the ball nut screwed together in this feed screw according to rotation of the feed screw extended to an up-down direction. The width of the gap 19 between the peripheral surface of the baking roller 7 and the peripheral surface of the heat removal roller 8 is preferably set to 50 mm or less.

  The drying device 4 further includes a plurality of guide rollers 15 and 16 and a nip roller 17 that presses the film 3 against the heat removal roller 8. The guide rollers 15 and 16 contact the one surface 1 of the film 3 and guide the film 3 in a desired direction. The circumference of the guide rollers 15 and 16 is a mirror surface, and both ends of the guide rollers 15 and 16 are supported by the housing. The nip roller 17 is provided with a friction material such as rubber on the peripheral surface, and causes the film 3 to travel by rotating with the rotational force of the electric motor.

  Although not shown, the expanding roller may be disposed at an appropriate position of the drying device 4. The expanding roller, for example, contacts the other surface 2 of the film 3 immediately before the film 3 contacts the preheating roller 5 or the drying roller 6, and exerts a frictional force that pushes the film 3 toward both ends of the preheating roller 5 or the drying roller 6. It is what happens.

  The temperatures of the four rollers 5 to 8 are set to be about 100 ° C, 140 ° C, 200 ° C, and 120 ° C in this order. The diameters of the peripheral surfaces of the four rollers 5 to 8 are 300 mm. The diameter of the peripheral surface of the guide rollers 15 and 16 is 100 mm. The film 3 is polyethylene terephthalate having a thickness of 0.1 mm. The thin film is formed by printing conductive ink on one surface 1 of the film 3 so as to have a thickness of about 0.01 mm or less. The temperature of the film 3 is normal temperature when the conductive ink is printed. The normal temperature means 25 ° C. or substantially the same temperature as the room temperature of a clean room or the like where the drying apparatus 4 is installed.

  The operation of the drying device 4 will be described. First, the height of the slider 12 of the support means 10 is adjusted so that the space 18 has a width of 50 mm or less. In the present embodiment, the width of the gap 18 is set to 20 to 30 mm in consideration of the material of the film 3, the thickness of the film 3, and the like. The nip roller 17 causes the film 3 to travel at a speed of 1 m / min.

  The film 3 sequentially contacts the preheating roller 5, the drying roller 6, and the baking roller 7, and the temperature of the film 3 is increased stepwise to 100 ° C. and 140 ° C. and further to about 200 ° C. that is the temperature of the baking roller 7. To do. For this reason, compared with the case where the film 3 is raised from normal temperature to the temperature of the baking roller 7 by one heat transfer, rapid expansion of the film 3 can be suppressed. Even if thermal stress occurs in the film 3, the film 3 is moderately tensioned and supported by the preheating roller 5, the drying roller 6, or the baking roller 7, so that the shape of the film 3 is not distorted. No wrinkles occur in 3. Further, since the conductive ink is baked (solidified) at about 200 ° C., the conductive ink is directly heated by the baking roller 7 while the one surface 1 of the film 3 is in contact with the baking roller 7. Conductive lines are formed on one side 1.

  Subsequently, the film 3 leaves the baking roller 7 and comes into contact with the heat removal roller 8 at about 120 ° C. The heat removal roller 8 acts as a medium for releasing the heat accumulated in the film 3 and the conductive wire. The nip roller 17 also acts as a similar medium. As a result, the film 3 is cooled to around 120 ° C., and further dissipated from the heat removal roller 8 until it reaches room temperature. Therefore, the temperature of the film 3 drops stepwise. For this reason, rapid contraction of the film 3 can be suppressed as compared with the case where the cooling of the film 3 heated by the baking roller 7 depends only on the heat radiation to the atmosphere. Even if thermal stress occurs in the film 3, the film 3 is moderately tensioned and supported by the heat removal roller 8, so that the shape of the film 3 is not distorted and wrinkles are generated in the film 3. Absent.

  According to the drying apparatus 4 described above, since the conductive ink can be quickly dried while the film 3 is in contact with the three rollers 5 to 7, a conductive wire having an extremely low electric resistance can be formed. Moreover, since no wrinkles occur in the film 3, a conductive wire with high dimensional accuracy can be formed.

  Further, since the preheating roller 5 and the drying roller 6 are in contact with the other surface 2 of the film 3, the solvent contained in the conductive ink evaporates from the one surface 1 of the film 3. For this reason, the vaporized solvent does not stay between the other surface 2 of the film 3 and the preheating roller 5 or between the other surface 2 of the film 3 and the drying roller 6. Thereafter, the baking roller 7 comes into contact with the one surface 1 of the film 3, but most of the solvent contained in the conductive ink has already evaporated by receiving heat from the preheating roller 5 and the drying roller 6. Since the surface has a dry property, the conductive ink does not stick to the baking roller 7.

  The guide roller 15 bends the film 3 between the preheating roller 5 and the drying roller 6, and travels from the drying roller 6 to the baking roller 7 for the distance traveled from the preheating roller 5 to the drying roller 6 of the film 3. It plays the role of making it longer than the distance. This is because the time margin required for heating the conductive ink is increased and the evaporation of the solvent contained in the conductive ink is promoted. Thus, there is an advantage that the speed at which the nip roller 17 travels the film 3 can be set faster as much as the evaporation of the solvent can be promoted.

  Further, the film 3 is strongly subjected to the radiant heat of the baking roller 7 when crossing the gap 18, and is heated to a temperature higher than that of the drying roller 6 before reaching the baking roller 7. For this reason, since the film 3 can suppress rapid expansion of the film 3 as compared with the case where the film 3 is heated from about 140 ° C. to 200 ° C. which is the temperature of the drying roller 6 when the film 3 comes into contact with the baking roller 7. The effect of preventing wrinkles of the film 3 becomes more remarkable. Further, since the film 3 receives strong radiant heat from the baking roller 7 while crossing the gap 19, the film 3 is separated from the baking roller 7 and reaches the heat removal roller 8. Can be suppressed. For this reason, the effect which prevents the wrinkle of the film 3 becomes further remarkable.

  It should be noted that the present invention can be implemented in variously modified, modified, or modified forms based on the knowledge of those skilled in the art without departing from the spirit of the present invention. For example, warm air heated by a heater or the like may be supplied around the preheating roller 5 and the drying roller 6. The preheating roller 5 may be omitted. Further, the interval at which the four rollers 5 to 8 are arranged can be changed in consideration of the amount of heat necessary for drying the conductive ink, the material of the film 3, the thickness of the film 3, and the like.

  The present invention is useful not only for the production of electronic components but also for drying liquids, powders, gels and the like applied to all film-like articles.

The side view which shows the outline of the drying apparatus which concerns on embodiment of this invention. The perspective view which shows the principal part of the drying apparatus which concerns on embodiment of this invention.

Explanation of symbols

1: One side 2: Other side 3: Film 4: Drying device 5: Preheating roller 6: Drying roller 7: Firing roller 8: Heat removal roller 9: Heating means

Claims (6)

A drying device for running a film having one side and the other side and drying a thin film applied to one side of the film,
A drying roller in contact with the other surface of the film, a baking roller in contact with one surface of the film, a heat removal roller in contact with the other surface of the film, and a heating means for individually heating these rollers,
The drying roller, the firing roller, and the heat removal roller are arranged in order according to the travel of the film, and the heating means sets the firing roller to the highest temperature among the drying roller, the firing roller, and the heat removal roller. A drying apparatus characterized by heating. A drying device for running a film having one side and the other side and drying a thin film applied to one side of the film,
A preheating roller that contacts the other surface of the film, a drying roller that contacts the other surface of the film, a baking roller that contacts one surface of the film, a heat removal roller that contacts the other surface of the film, and Heating means for individually heating the rollers,
The preheating roller, the drying roller, the baking roller, and the heat removal roller are arranged in the order according to the travel of the film, and the heating means includes the preheating roller, the heat removal roller, the drying roller, and the baking roller in that order. A drying apparatus characterized by heating so as to increase the temperature.   The drying apparatus according to claim 1, wherein the drying roller and the baking roller separate a gap of 50 mm or less.   The drying apparatus according to any one of claims 1 to 3, wherein the baking roller and the heat removal roller separate a gap of 50 mm or less. It is a drying method of running a film having one side and the other side, and drying a thin film applied to one side of the film,
A drying step of transferring heat to the other surface of the film and heating the thin film;
A baking step of transferring heat to one surface of the film and heating the thin film to a temperature higher than the drying step;
A heat removal step of transferring heat from the film heated in the baking step toward a medium having a temperature lower than that of the film heated in the baking step;
A drying method characterized by performing. It is a drying method of running a film having one side and the other side, and drying a thin film applied to one side of the film,
A drying step of transferring heat to the thin film by contacting a drying roller with the other surface of the film and heating the drying roller;
A baking step of contacting the baking roller on one surface of the film and transferring the heat to the thin film by heating the baking roller to a temperature higher than that of the drying roller;
A heat removal step of transferring heat from the film heated in the baking step toward a medium having a temperature lower than that of the film heated in the baking step;
Drying method characterized by performing

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