JP4173330B2 - Coating film drying apparatus and coating film drying method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a coating film drying apparatus and film drying way to dry the coating film formed on the coating object.
[0002]
[Prior art]
Since optical products and liquid crystal related members need to be applied and dried with high accuracy, it is necessary to dry the coated film without disturbing the coated surface after being coated.
Therefore, coating film drying prevents the coating surface from being disturbed by blowing hot air from the back of the web and drying it so that it cannot be directly blown from the top of the coating formed on the surface of the web. The device is used.
[0003]
FIG. 3 is a schematic diagram showing the configuration and operation of a conventional coating film drying apparatus.
The coating film drying apparatus 20 includes a coat unit 11, a drying furnace 22, and a plurality of rolls 13a to 13c.
[0004]
The coat unit 11 includes an impression cylinder 11a, a blanket cylinder 11b, and a plate cylinder 11c adjacent to each other in order.
The drying furnace 22 includes a web lower surface air supply nozzle 24 and an exhaust nozzle 15. The web lower surface air supply nozzle 24 is provided near the lower surface of the web 16 and includes a slit 26 having a width of about 0.5 to 5 mm in the web width direction, and hot air is supplied from the slit 26. Further, the width of the web lower surface air supply nozzle 24 is generally larger than the web width in order to uniformly dry the entire width direction of the coating film surface. The exhaust nozzle 15 is provided in a flow path of hot air discharged from the web lower surface supply nozzle 24 on the lower surface of the web 16, and discharges the hot air used for drying to the outside of the drying furnace 22.
[0005]
The web 16 is made constant in tension by the roll 13 a and travels into the coat portion 11 to enter. When the web 16 enters the coating portion 11, the back surface is wound around the impression cylinder 11a, and the coating liquid is transferred to the front surface via the blanket cylinder 11b from which the coating liquid is transferred from the plate cylinder 11c. It is formed, travels in the direction of arrow X while being kept constant in tension by the roll 13 b, and enters the drying furnace 22.
When the web 16 travels in the drying furnace 22, the coating surface on the surface of the web 16 is dried from the back surface of the web 16 while being lifted by hot air blown from the web lower surface air supply nozzle 24 in the direction of arrow B. The
[0006]
[Problems to be solved by the invention]
FIG. 4 is an enlarged schematic diagram showing the configuration of the coating film drying air supply nozzle of FIG. 3 and the situation in which hot air wraps around the coating film.
In the web lower surface air supply nozzle 24, the width of the web lower surface air supply nozzle 24 is made larger than the width of the web 16 in order to float the web 16.
However, the problem is that the hot air blown from both ends in the width direction of the web lower surface air supply nozzle 24 wraps around the both ends of the coating film 17 on the upper surface of the web 16 as indicated by arrows C, and both ends of the coating film 17 are disturbed. There is.
[0007]
An object of the present invention, without disturbing the coating film surface, and without lowering the drying efficiency, to provide a coating film drying apparatus and film drying method Ru can perform drying of the coating film is there.
[0010]
[Means for Solving the Problems]
In order to solve the above-described problems, the invention according to claim 1 is directed to spraying a drying gas on the lower surface of the traveling surface of the object to be coated, and applying the gas to the upper surface of the object to be coated while floating the object to be coated. A coating film drying apparatus for drying a coating film, which is disposed on the lower surface side of the traveling surface of the object to be coated, has a gas supply part (14b) including a porous member on the entire surface, and the drying gas A coating film drying and supply nozzle (14) for supplying air, wherein the drying gas passes through the gas supply section and is sprayed onto the lower surface of the traveling surface of the object to be coated. It is a drying device.
[0011]
The invention according to claim 2 includes a drying step of drying the coating film applied to the upper surface of the object to be coated while spraying a drying gas on the lower surface of the traveling surface of the object to be coated and floating the object to be coated. a coating film drying method, the drying step, the coating film drying method of to supply air to the drying gas passing through the porous member at a low fluid speed and wide fluid sectional area (14b), the said It is.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic diagram showing the configuration of a coating film drying apparatus provided with a coating film drying and supply nozzle according to an embodiment of the present invention and the operation of the coating film drying apparatus.
In the following, parts having the same functions as those of the above-described conventional technology are denoted by the same reference numerals, and repeated description is appropriately omitted.
The coating film drying measure 10 includes a coating unit 11 that coats the web 16 as an object to be coated, a drying furnace 12 that dries the coated web 16, and a plurality of rolls 13 a to 13 that run the web 16 with a constant tension. 13c.
[0013]
The drying furnace 12 includes a web lower surface air supply nozzle 14 and an exhaust nozzle 15 inside.
A plurality of web lower surface air supply nozzles 14 are provided in the vicinity of the lower surface of the web 16 in the direction of travel of the web 16 at a predetermined interval. Further, the web lower surface air supply nozzle 14 is provided such that the longitudinal direction thereof is orthogonal to the traveling direction of the web 16.
The exhaust nozzle 15 is a nozzle that discharges hot air discharged from the web lower surface supply nozzle 14 as a gas supply unit to the outside of the drying furnace 12.
[0014]
FIG. 2 is an enlarged schematic view showing the configuration of the coating film drying air supply nozzle of FIG. 1 and the flow path of hot air.
The web lower surface air supply nozzle 14 includes a hot air nozzle 14a and a hot air supply unit 14b. The hot air supply unit 14b covers the entire surface of the hot air outlet of the hot air nozzle 14a and includes a porous member. The porous member is made of a porous sintered material.
The porous sintered material refers to a material in which powders or compacted particles are heated and combined to form a large number of pores or voids therein.
In the present embodiment, as the porous sintered material, aluminum, zinc, copper or the like is used, the porosity indicating the degree of porosity is 50% or less, the thickness is 3 to 30 mm, the pore size is 0.1 to 1 mm, A wind speed of 0.5 to 20 m / s is used.
[0015]
Next, the coating film drying operation by the web lower surface air supply nozzle 14 according to the present embodiment will be described.
As shown in FIG. 1, the web 16 is wound around a roll 13 a and travels with a constant tension, is applied by the coat unit 11, and enters the drying furnace 12 through the roll 13 b.
[0016]
When the web 16 enters the drying furnace 12, as shown in FIG. 2, hot air as a drying gas flowing in the hot air nozzle 14a passes through the hot air supply section 14b and blows to the back surface of the web 16. The coating film 17 applied to the surface of the web 16 travels in the direction of arrow X in FIGS. 1 and 2 while being dried.
[0017]
When the hot air passes through the porous sintered material of the hot air supply section 14b, the porous air circulates between the meshes because the pores are stretched around inside the porous sintered material. Hot air is supplied from the entire surface. Since air is supplied from the entire surface, air is supplied with a wide fluid cross-sectional area.
Moreover, since the mesh-shaped holes are intricately arranged inside the hot air supply section 14b, the hot air collides everywhere in the flow path while flowing. Since the air supply area is large, the wind speed is reduced even if the air supply amount is large.
In this way, the hot air is blown from the hot air supply unit 14b at a low fluid velocity and has a wide fluid cross-sectional area, and is blown to the lower surface of the web 16 as indicated by an arrow A (drying process).
[0018]
According to the present embodiment, since the hot air supply section includes the porous sintered material, hot air having a low fluid velocity and a wide fluid cross-sectional area can be derived.
Since the hot air has a low fluid velocity, the hot air does not wrap around the upper surface of the web 16 even when blown from the air supply surface wider than the web width, and the surface of the coating film 17, particularly the coating film 17. Both end portions in the width direction on the surface of the surface are dried without being disturbed.
In addition, since the hot air has a wide fluid cross-sectional area, a wide area web can be levitated and dried even at a low wind speed.
Furthermore, since the hot air has a wide fluid cross-sectional area, the drying efficiency does not decrease, and the drying efficiency does not deteriorate due to the low wind speed.
[0019]
(Deformation)
The present invention is not limited to the embodiment described above, and various modifications and changes are possible, and these are also within the equivalent scope of the present invention.
(1) In this embodiment, a web is used as an object to be coated, but a sheet or the like may be used.
[0020]
(2) In the present embodiment, a porous sintered material is used as the porous material. However, as long as the porous material is used, a material having a fine net or honeycomb-like hole may be used.
[0021]
(3) In this embodiment, hot air is used as the drying gas. However, as long as it is a gas that can be used for drying, a gas having a wetness of 0 or another gas having a hygroscopic property may be used.
[0022]
(4) In the present embodiment, the entire surface of the gas supply unit is a porous member, but a porous member may be used in a predetermined range of the gas supply unit.
[0023]
【The invention's effect】
As described above in detail, the present invention has the following effects.
(1) Since the gas supply unit includes a porous member through which the drying gas passes, the drying gas can be blown out by being changed to a low fluid velocity by the porous member.
[0024]
(2) Since the porous member is provided on the entire surface of the gas supply unit, the drying gas is changed to a wider fluid cross-sectional area and blown out as compared with the case where the porous member is provided in a part of the gas supply unit. Can do.
[0025]
(3) Since the drying gas passes through the gas supply section composed of the porous material and is sprayed on the lower surface of the object to be coated, the coating surface is not disturbed and the drying efficiency is not reduced. The coating film can be dried.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing the configuration of a coating film drying apparatus provided with a coating film drying and supply nozzle according to an embodiment of the present invention and the operation of the coating film drying apparatus.
2 is an enlarged schematic view showing a configuration of a coating film drying air supply nozzle of FIG. 1 and a flow path of hot air.
FIG. 3 is a schematic diagram showing the configuration and operation of a conventional coating film drying apparatus.
4 is an enlarged schematic view showing a configuration of a coating film drying / supplying nozzle of FIG. 3 and a situation in which hot air wraps around the coating film.
[Explanation of symbols]
14 Web lower surface air supply nozzle 14a Hot air nozzle 14b Hot air supply unit 16 Web 17 Coating film

Claims (2)

A coating film drying apparatus that blows a drying gas on the lower surface of the traveling surface of the object to be coated, and dries the coating film applied to the upper surface of the object to be coated while floating the object,
It is disposed on the lower surface side of the traveling surface of the object to be coated, has a gas air supply portion including a porous member on the entire surface, and includes a coating film drying air supply nozzle for supplying the drying gas,
The drying gas passes through the gas supply section and is sprayed on the lower surface of the traveling surface of the object to be coated;
A coating film drying apparatus characterized by the above. A coating film drying method comprising a drying step of drying a coating film applied to the upper surface of the coating object while spraying a drying gas on the lower surface of the traveling surface of the coating object, and floating the coating object,
The drying step is to supply air to the drying gas passing through the porous member at a low fluid speed and wide fluid sectional area,
A coating film drying method characterized by the above.

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