JPH105666A - Die coater and continuous coating of sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a die coater applying continuous coating to the surface of the sheet continuously transferred in opposed relation to a lip and capable of accurately adjusting the gap between the lip and the sheet and a method for continuously coating the sheet using the die coater. SOLUTION: This die coater is equipped with a die 1 having a manifold 3 formed therein along its longitudinal direction and having a coating agent emitting slot 14 continued to the manifold 13 formed thereto and having a lip 14c forming the opening part of the slot 14 formed to the front edge thereof in its longitudinal direction and continuous coating is applied to the surface of a sheet S continuously transferred in opposed relation to the lip 14c. In this case, a guide plate 17 along which the coating agent overflowing from the gap between the lip 14c and the sheet S flows down is provided under the lip 14c along the longitudinal direction of the lip 14c.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a die coater, and more particularly, to a surface of a sheet which is continuously conveyed in opposition to a lip disposed at a leading edge of a die by paint discharged from between the lips. The present invention relates to a die coater capable of accurately adjusting a gap between a lip and a sheet surface, and a method for continuously coating a sheet using the die coater.

[0002]

2. Description of the Related Art A die coater is a device for applying a continuous coating to a surface of a sheet which is continuously conveyed in opposition to its leading edge. And a die having a slot for discharging paint. At the front edge of the die, a lip forming the opening of the slot is provided along the longitudinal direction, and is configured to apply a continuous coating to the sheet surface with a paint discharged from between the lips. .

[0003] Regarding the novel technology relating to the die coater,
The present applicant has a die coater (JP-A-6-198240) that can easily adjust the coating width without disassembling the die, and can efficiently and easily change the paint without disassembling the die. Die coater (Japanese Patent Laid-Open No. 6-47334)
Has already filed a patent application.

[0004]

By the way, in the continuous coating of the sheet using the die coater, the gap between the lip and the sheet surface greatly affects the coating state. That is, if the gap is too wide, the coating pressure on the sheet surface is insufficient, and coating unevenness or coating breakage occurs. On the contrary,
If the gap is too narrow, the space volume of the gap becomes smaller than the discharge amount of the paint, and the paint overflows uselessly from the gap, and the coating thickness on the sheet surface also becomes thin. In addition, since the sheet is continuously transported, the surface is slightly shaken, and if the gap is too narrow, the lip may come into contact with the sheet surface to damage the sheet surface.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a die coater for applying a continuous coating to a surface of a sheet which is continuously conveyed in opposition to a lip. It is an object of the present invention to provide a die coater capable of precisely adjusting a gap between the sheet and a continuous coating method of a sheet using the die coater.

[0006]

In order to solve the above-mentioned problems, a die coater according to the present invention has a manifold formed therein along a longitudinal direction and a paint discharge slot continuous with the manifold. A die provided with a lip forming an opening of the slot along the longitudinal direction thereof, and a die coater for applying a continuous coating to a surface of a sheet continuously conveyed in opposition to the lip. A guide plate is provided along the longitudinal direction of the lip to allow the paint overflowing from between the lip and the sheet surface to flow down.

In the die coater of the present invention, preferably, a die adjusting device for finely adjusting the gap between the lip of the die and the sheet surface is provided. Further, it is preferable to provide a receiving gutter below the guide plate for receiving the paint dripped from the lower edge of the guide plate.

[0008] Further, the continuous coating method for a sheet according to the present invention comprises:
In continuously coating the surface of the sheet using the die coater, adjusting the gap between the lip and the sheet according to the amount of paint flowing down on the guide plate surface or the amount of paint dripped from the lower edge of the guide plate to the receiving gutter. It is characterized by.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a die coater according to the present invention will be described below with reference to the drawings. FIG. 1 is a schematic side view of a die coater according to the present invention, and FIG. 2 is a schematic front view of the die coater.

[0010] The die coater of the present invention, as shown in FIG.
A manifold (13) and a slot (14) for paint discharge continuous with the manifold (13) are formed inside the manifold (13) along the longitudinal direction, and a pair of upper and lower parts forming an opening of the slot (14) at the front edge. A lip (14c) is provided with a die (1) provided along a longitudinal direction. The surface of the sheet (S) which is continuously conveyed to face the lip (14c) is continuously coated with the paint discharged from between the lips (14c) and (14c).

The die (1) is constituted by upper and lower molds (11) and (12). And, between the upper and lower molds (11) and (12), that is, between the separation surfaces on the front side of the upper and lower molds, the manifold (13) and the paint discharge slot (14) continuous therewith. Are formed. Lips (14c) forming the openings of the slots (14) are formed on the front edges of the upper and lower molds (11) and (12), respectively.

In the die (1), as shown in FIG. 2, a pair of thin deckles (3) are interposed in a slot (14) in a liquid-tight manner in order to adjust a coating width. .
Each deckle (3) is provided at the tip of a pipe-shaped deckle shaft (2) inserted from the opening at both ends of the manifold (13), and each deckle shaft (2) is a motor, a ball screw, or the like. Is configured to be movable in the manifold (13) by a moving mechanism (7) including By moving the deckle shaft (2), the distance between the deckles (3) is changed, and the coating width is adjusted.

The paint used for the coating is applied from the base end side of each deckle shaft (2) through a space (hereinafter referred to as a paint flow path) in the deckle shaft (2) to a die (hereinafter referred to as a paint passage). 1) is supplied to the manifold (13). The upper and lower lips (14c), (14c) are passed through slots (14) whose width is defined by each deckle (3).
c) It is discharged from between. The supply amount and the supply pressure of the paint are determined according to the gap distance of the slot (14), the coating width, the coating speed, and the like. Further, in the die (1), a flow path blocking pig (not shown) is slidably inserted into the paint flow path of the deckle shaft (2) in a liquid-tight manner.
A mechanism for changing the paint (color change) by selectively blocking the paint flow path of any one of the deckle shafts (2) may be provided.

Further, the die coater of the present invention comprises a die (1)
In order to precisely and finely adjust the gap between the lip (14c) and the surface of the sheet (S), for example, by rotating a driving screw such as a ball screw by operating a manual handle,
A die adjustment device (not shown) for bringing the entire die coater closer to or away from the surface of the sheet (S) is provided.

The sheet (S) is wound around a backup roll (9) disposed in front of the die (1), and is continuously transported upward immediately before the lip (14c) by a transport device (not shown). You. Examples of the sheet (S) include a thin plate such as aluminum, stainless steel, steel, and plated steel, and a resin film such as PET.
Its thickness is usually about 0.05 to 1 mm. on the other hand,
Examples of the paint include a clear paint containing a fluorine resin, a polyester resin, or the like as a component, a metallic paint containing aluminum powder or brass powder as a metallic pigment, and an acrylic resin or an alkyd resin as a vehicle resin component. .

The backup roll (9) for winding and supporting the sheet (S) needs to have a higher hardness than the sheet (S), and usually a metal roll is used. The backup roll (9) also functions as a transport roll of the transport line for the sheet (S), is disposed to face the lip (14c) of the die (1), and
With respect to c), the surface of the sheet (S) is maintained at a constant distance. Lip (14c) and seat (S)
The gap with the surface depends on the viscosity of the paint, etc., for example,
It is about 0.01 to 0.5 mm.

The axial length of the backup roll (9) is set longer than the width of the sheet (S). The diameter of the backup roll (9) is set based on the material and thickness of the sheet (S), the viscosity of the paint, and the like. Such a diameter is
The sheet (S) is large enough to support the sheet (S) with a curvature that does not allow the paint applied to the surface to flow.
About 1000 mm. The pass line of the sheet (S) near the die (1) usually has a backup roll (9) in order to enhance the adhesion of the paint applied to the surface thereof.
On the other hand, the line is wound from substantially downward to substantially upward.

In the die coater of the present invention, a guide plate (17) is provided below the lip (14c) to allow the paint overflowing from the gap between the lip (14c) and the surface of the sheet (S) to flow down. ) Are provided along the longitudinal direction. That is, the guide plate (17) is screwed, for example, to the lower mold (12) while maintaining a substantially vertical posture in which the upper end faces directly below the lip (14c). The material of the guide plate (17) is not particularly limited as long as it has high solvent resistance, but is generally made of a stainless steel plate or the like. Also, this guide plate (17)
In order to make it easy to visually confirm the flowing state of the paint, for example, it is preferable that the paint color be black when the paint color is light, and white when the paint color is dark, You may comprise with resin.

Further, below the guide plate (17),
A receiving gutter (18) for receiving the paint dripped from the lower edge of the guide plate (17) is provided. This gutter (18)
It is made of the same material as the guide plate (17), and is given the same coloring as the guide plate (17). The receiving gutter (18) is arranged on the installation surface of the die coater or is screwed to the lower mold (12) via a stay, but is integrally formed with the guide plate (17). May be.

In the die coater configured as described above, the surface of the sheet (S) which is continuously transferred from the lower side to the upper side on the backup roll (9) at a constant speed is applied to the die (1). By discharging the paint at a constant flow rate from between the lips (14c) and (14c), a continuous coating is applied to the surface of the sheet (S).

In the coating process using such a die coater, if the paint overflows from the gap between the lip (14c) and the surface of the sheet (S), the overflowed paint flows down the surface of the guide plate (17). I do. When the amount of paint flowing down is large, the paint is dripped from the lower edge of the guide plate (17) into the receiving gutter (18). Therefore, the guide plate (1
By visually observing the surface of 7) or the inside of the receiving gutter (18), the overflow of the paint and the degree thereof are confirmed.

As a result of visual inspection, if it is determined that the paint overflows too much, the die (1) as a whole is slightly separated from the sheet (S) side by a die adjusting device (not shown). As a result, if the paint overflow decreases, the lip (1
Since the gap between 4c) and the surface of the sheet (S) approaches an appropriate range, the die (1) is separated until the paint overflows. If the gap between the lip (14c) and the surface of the sheet (S) is too wide, the overflow of the paint increases and drops off. In this case, the die (1) is conversely placed on the sheet (S). Slightly closer to the side. Thereby, the sheet (S)
The coating thickness on the sheet (S) surface can be maintained in an appropriate range by preventing the unevenness of coating on the surface and the occurrence of coating breakage beforehand. Further, it is possible to prevent wasteful overflow of the paint and damage to the surface of the sheet (S) due to contact of the lip (14c) with the surface of the sheet (S). In addition, even if the die (1) is moved closer to or away from the sheet (S) by the fine adjustment device, if there is no large change in the overflow amount of the paint, there is an abnormality in the paint supply device or the paint supply path. Judge and deal with this.

[0023]

As described above, according to the present invention, when the paint overflows from the gap between the lip and the sheet surface, the overflowed paint flows down the guide plate surface and from the lower edge thereof. Drop into gutter. Therefore, by visually observing the guide plate surface or the inside of the gutter, it is possible to check the overflow of the paint and the degree thereof, and it is possible to find an abnormality in the paint supply device and the paint flow path according to the check result. Becomes If the paint overflows too much, the die is slightly separated from the sheet side, and if the paint overflows due to excessive separation, the die is moved slightly closer to the sheet side to reduce the lip. The gap with the sheet surface can be adjusted accurately. As a result, it is possible to prevent the occurrence of coating unevenness and coating breakage, to maintain the coating thickness on the sheet surface within an appropriate range, and also to prevent unnecessary overflow of paint and damage to the sheet surface. I can do it.

[Brief description of the drawings]

FIG. 1 is a schematic side view of a die coater according to the present invention.

FIG. 2 is a schematic front view of the die coater.

[Explanation of symbols]

 1: Die 2: Dickel shaft 3: Dickel 7: Moving mechanism 9: Backup roll 11: Upper mold 12: Lower mold 13: Manifold 14: Slot 14c: Lip 17: Guide plate 18: Receiving trough

Claims (4)

[Claims] 1. A manifold and a paint discharge slot continuous with the manifold are formed inside the manifold along a longitudinal direction, and a lip forming an opening of the slot is provided at a front edge along the longitudinal direction. A die plate for continuously coating the surface of a sheet continuously transferred to face the lip, wherein a guide plate for flowing down the paint overflowing from between the lip and the sheet surface below the lip. Is provided along the longitudinal direction of the lip. 2. The die coater according to claim 1, further comprising a die adjusting device for finely adjusting the gap between the die lip and the sheet surface. 3. The die coater according to claim 1, wherein a receiving gutter for receiving paint dripped from a lower edge of the guide plate is provided below the guide plate. 4. A continuous coating of a sheet surface using the die coater according to claim 2 or 3, depending on the amount of paint flowing down on the guide plate surface or the amount of paint dripped from the lower edge of the guide plate to the receiving gutter. A continuous coating method for a sheet, wherein a gap between the lip and the sheet is adjusted.