EP1861206A1

EP1861206A1 - Curtain application unit

Info

Publication number: EP1861206A1
Application number: EP06707754A
Authority: EP
Inventors: Hirofumi Morita; Akio Hirano; Hiroyuki Kohno
Original assignee: Voith Patent GmbH
Current assignee: Voith Patent GmbH
Priority date: 2005-03-11
Filing date: 2006-01-19
Publication date: 2007-12-05
Anticipated expiration: 2026-01-19
Also published as: WO2006094854A1; ATE446811T1; EP1861206B1; JP4683968B2; US7556693B2; CN101237943A; DE502006005239D1; US20080006203A1; CN101237943B; JP2006247559A

Abstract

This invention relates to a curtain applicator on which a two-layer curtain is formed by dispensing two types of coating medium, for example color, from a medium feeder positioned to the upper side of a moving web in order to apply two layers of coating medium onto the web surface. The medium feeder has a middle lip, which is arranged in the flow channels for the two types of medium and has a pointed part projecting toward the web side from the pointed parts of the two side lips which are arranged on the outer side of the flow channels for the two types of medium on the outer side in the width direction of the web. The curtain applicator also includes a convexly formed medium separation device, which adjoins the pointed part of the middle lip and individually separates the two types of surplus medium, for example, color, which are dispensed from the medium feeder.

Description

CURTAIN OF CONTRACT WORK

The present invention relates to a curtain applicator used for applying coating medium, for example, two-layer paint on a web surface.

Heretofore, in the production of coated paper for use as general printing paper, for example, catalogs, etc., pressure-sensitive paper, heat-sensitive paper, and card stock for automatic ticket dispensers have been used after applying paint to a base paper web using a paper web ordinary post-dosing applicator (a knife coater, etc.) dosages. Machines used for such paint application are commonly referred to as commissioned works.

So far, these most common applicators use a post-dosing method in which dosing is performed after paint is applied to a web surface.

In recent years, instead of the paint applying step using a post-dosing applicator, curtain applicators 100 have been widely used in which, as shown in the schematic cross section of the main part of Fig. 4, a color ta by discharging from an upper curtain head 101 the web w traveling in the direction of the arrow is applied to form a color curtain.

It should be understood that the references below refer to examples of previously disclosed inventions relating to this application. Cited document 1, Japanese Patent No. S63-23

Quoted font 2, Unexamined Japanese Utility Model Application No. H04-131700.

Problems to be solved by the invention:

There are two methods of application available as a method of applying two layers of the colors tb, tc to one surface of the web w using the curtain applicator described above.

In the first application method thereof, as shown in the schematic cross section of the main part of Fig. 5, the colors tb, tc are discharged from upper curtain heads 201, 202 onto an arrow-directional web w to form individual monolayer color curtains cb, cc and Figs Apply colors tb, tc in two layers to the surface of the web w. In this application method, the second layer of color tc is applied before drying the first layer of color tb applied to the surface of the web w.

However, in this application method, when the amount of colors tb, tc discharged from the curtain heads 201, 202 is small, for example, less than 4 to 6 l / min per web width m, the color curtains cb, cc are not very strong and can not used to form a normal curtain. Furthermore, by blowing air over the applicator 200, slippage of the color curtains cb, cc is effected, and the formation of a normal coating is prevented.

In the second application method, as shown in the schematic cross section of the main part of Figure 6 a and Figure 6 b, which is a view along the direction of arrow A of Figure 6 a, by curtain heads 301, 302 two-layered in advance

Color curtains cd, ce formed, and the order is made by the two-layer color curtains cd, ce on the running in the direction of the arrow w. In this application method, the flow velocities of the two curtains cd, ce are balanced to form the two-layer color curtains cd, ce, and if, for example, the flow rates of each of the color curtains cd, ce is 5 l / min • web width m, the total flow speed generated is 10 l / min • web width m, and the inertial force is increased, which leads to strengthening and stabilizing the color curtain and the implementation of a stable coating.

As shown in Figure 6b, when using a curtain applicator 300 for application in which the curtain width is greater than the web width ws when the portion of the curtain facing away from the

Web width protrudes, is collected by the recovery color cup cp1, but the two colors td, te mixed, as shown in Figure 6 a. For this reason, when colors with different properties are to be applied, the reuse of the mixed colors td, te is difficult, and it comes to a

Loss of production.

In the first application method as described above, on the other hand, each of the colors tb, tc can be individually recovered because the color curtains cb, cc are completely separated.

Both methods have advantages and disadvantages, and consequently the existing curtain coating works used to perform a two-layer job have problems.

Object of the invention:

In view of the above, an object of the present invention is to provide a curtain coater in which, when performing a two-layer application on a web surface, the excess color of the color curtain edge portions can be separated and recovered, and moreover the color curtain stabilizes and a uniform coating can be carried out.

Means of solving the problems - A -

To achieve the object, in the curtain applicator of claim 1 of the present invention, which is a curtain applicator in which two color layers are dispensed by dispensing two dyes from a paint supply device to the top of a moving web for applying two color layers to the web surface Color curtain is formed, the paint supply device, a middle lip, which is arranged in the flow channels for the two color grades and having a tip portion of the tip portions of the two side lips, in the outside of the flow channels for the two color in the outside in the width direction of the web and a convex-shaped ink releasing agent abutting the tip portion of the middle lip and separating the two kinds of excess paint discharged from the paint supply device one by one.

Furthermore, the curtain applicator according to claim 2 of the present invention comprises a first moving device for moving the color separating agent in the web width direction according to claim 1.

Further, the curtain applicator according to claim 3 of the present invention according to claim 1 or 2 comprises a plate-shaped guide means which is arranged in the web side of the color separating means for aligning the edge part of the color curtain.

Furthermore, the curtain applicator according to claim 4 of the present invention comprises a second moving device for moving the guide means in the web width direction according to claim 3.

Effect of the invention:

As described above, on the basis of the curtain applicator according to claim 1 of the present invention, due to the fact that the above-mentioned paint supply device comprises a middle lip disposed in the flow channels for the two colors and having a tip portion that is separated from the tip portions of the Figs both Side lips, which are arranged in the outer side of the flow channels for the two Farbarten in the outer side in the width direction of the web, the web side, and a convex-shaped color separating means, which abuts the tip portion of the middle lip and the two types of excess paint, the Separate paint supply device, the excess of each of the colors that are not used for coating, separated and recovered individually.

For this reason, the recovered color can be reused, and the color loss in the application process can be reduced as much as possible.

On the basis of the curtain applicator according to claim 2 of the present invention, due to the fact that it comprises a first moving device for moving the color separating agent in the web width direction, the excess colors can be separated and recovered individually by the movement of the color separating agent irrespective of the size of the web width dimension become.

On the basis of the curtain applicator according to claim 3 of the present invention, due to the fact that it further comprises a plate-shaped guide means for aligning the edge portion of the color curtain disposed in the web side of the color separator of the color curtain, stabilization of the color curtain edge portion can be achieved.

On the basis of the curtain applicator of claim 4 of the present invention, due to the fact that it comprises a second moving device for moving the web width directional means, the excess colors can be separated and recovered individually by moving the color separating agent, irrespective of the size of the web width dimensions ,

In the description of the invention is mainly spoken of "color" or color-separating agents, colors, color curtain, but it should be It should be noted that the invention relates generally to the application of a coating medium.

The following is a description of an embodiment of the present invention with reference to the accompanying drawings.

Show it:

FIG. 1 is a schematic front view of the embodiment of the present invention

Curtain applicator unit.

FIG. 2 a shows a cross section along the line B - B of FIG. 1.

FIG. 2 b shows a cross section along the line C - C of FIG. 1.

Figure 3 a: an enlarged view of the central lip and the partition plate, which are shown in Figure 2 b.

FIG. 3 b shows a schematic cross section of a modified example of the separating plate and the storage container.

Figure 4 is a schematic cross-sectional view of the main part of an example of a prior art curtain coating apparatus.

Figure 5 is a schematic cross section of the main part of an example of a two-layer curtain coating device according to the

State of the art.

FIG. 6 a shows a schematic cross section of the main part of another

Example of a prior art two-layer curtain applicator.

Figure 6b is a view along the direction of arrow A of Figure 6a. Fig. 1 is a schematic front view of a curtain applicator 10 of an embodiment to which the present invention is applied, and Fig. 2 a is a cross section taken along the line BB of Fig. 1 and Fig. 2 b is a cross section taken along the line CC of Fig 1.

The curtain applicator 10 outputs a color ta of a first curtain head 11 or a color tb of a second curtain head 12 by means of a color feeder N, whereupon two layers of colors are formed to form two-layer color curtains ca, cb (see FIG. 2 a) ta, tb are applied to an area of the web w running in the direction of the arrow.

The curtain coater 10 produces a stable color curtain area in its central area by delivering, as shown in Figure 1, the two-layer color curtains ca, cb in widths greater than the web width ws, whereupon the coating is implemented with uniform color curtains.

It should be noted that, as shown in Figure 2a, between the flow channels 11a, 12a of the first curtain head 11 and the second curtain head 12 formed angle θ is set between 15 and 30 °. The angle θ is preferably in this prescribed range of values because the dimensions of the ink supply device N would be too large if it were larger.

Further, as shown in Figs. 1 and 2b, the excessive colors ta1, tb1 on the outside in the widthwise direction of the web which are not used to coat the web surface are separated and collected by special recovery paint cups cp1, cp2 individually.

In this way, the recovered colors ta1, tb1 are returned to supply containers (not shown in the drawings) for each of the colors ta, tb, and they are recirculated and returned to the first curtain head 11 and the second curtain head 12, respectively. To increase the stability between the colors used for coating ta, tb and the separately separated excess colors ta1, tb1, which are not used for coating, as shown in Figure 1, guide plates (plate-shaped guide means) gp, gp for aligning the edge portions the color curtains ca, cb provided.

The guide plates gp, gp stabilize the color curtains ca, cb and divide them into colors ta, tb used for coating and individually separated excess colors ta1, tb1, which are not used for coating.

That is, by the movable guide plates gp, gp, which are arranged in the outside in the width direction of the web, the width of the color curtains ca, cb, which are used directly for coating the surface of the web w, can be optimally adjusted to with the Width ws of the web to be coated w to match.

The guide plates gp, gp are made of a flexible sheet or the like, and in order to prevent resistance to the liquid flow of the curtains, they are configured with a smooth surface

In the present embodiment, the flow of the colors ta, tb is improved, and stable color curtains ca, cb can be formed by, for example, attaching a polypropylene film having a thickness of 50 to 100 μm to a thin brass or aluminum plate and keeping the color curtains approx , cb be aligned by the polypropylene plate.

In order to improve the flow of the colors ta, tb in the contact area with the guide plates gp and to prevent interference with the color curtains ca, cb, the guide plates gp contacting the color curtains ca, cb preferably form a member having a smooth surface and a low coefficient of friction.

It should be noted that, as shown in Figure 1, due to the low interference of the curtains, in the contact area between the Edge portions of the color curtains ca, cb and the guide plates gp occurs, in a region between the web w and the guide plates gp a gap with the dimension d1 (= 3 to 5 mm) is generated, and the colors ta2, tb2 this area, not used for the coating are collected by the color recovery tray cp3.

It should be noted that the guide plates gp can be bent and plastically deformed due to their configuration of a thin metal plate and a propylene foil, whereupon the optimum shape of the guide plates gp for producing a stable color curtain can be easily produced.

FIG. 3 a is an enlarged view along the middle lip N 1 and partition plate p b as shown in FIG. 2 b.

The configuration shown in Figure 2 b and Figure 3 a forms a configuration in which the excess colors ta1, tb1, which are not used for the coating, can be separated individually.

That is, a tip part N11 of a middle lip N1 interposed between the flow channels 11a, 12a of a two-layer paint supply device N is provided to be 0.5 to 10 mm (dimension d of Fig. 3a) from the tip part N21 of the two side lips N2, N2 of the outside of the flow channels 11a, 12a down to the web w side protrudes. It should be noted that the dimension d, by which the tip portion N11 of the middle lip N1 projects down from the tip portions N21, N21 of the two side lips N2, N2 toward the web side, is not limited to this value and can exceed it by 10 mm ,

In addition, a partition plate (the color separating means) pb of a curved projecting shape abuts the tip part N11 of the middle lip N1, and spatially separates the two discharged kinds of the colors ta, tb so as to separate the two colors ta, tb one by one without mixing.

As shown in Fig. 3a, each of the excess colors ta1, tb1 flows through the middle lip N1 and the partition plate pb without mixing be separated, along the partition plate pb and falls into storage containers pd, pc2 down.

Since the storage containers pd, pc2, which collect the colors ta1, tb1, as shown in Figure 1, a sloping to the special recovery shells cp1, cp2 inclination, the color ta1 of the storage container pd and the color tb2 of the storage container pc2 to the special Recovery cups cp1 and cp2, respectively, flow where they are recovered.

As shown in Fig. 3a, here, in order to prevent the middle lip N1 from being damaged due to abutment of the partition plate pb on the tip part N11 of the middle lip N1, an elastic material (color-separating agent) pb1 such as a rubber sheet or a resin material is attached. It should be noted that even a configuration in which no elastic material pb1 is used and instead the partition plate pb itself is elastic can be used.

Although the present invention exemplifies an example in which the partition plate pb and the storage containers pd, pc2 are integrally formed by using a stainless steel bent plate as shown in Fig. 3b, the separator plate (color separator) pb2 and the storage containers pc11, pc21 also be provided separately. As long as the partition plate is configured to protrude and abut the tip portion N11 of the middle lip N1 to separate the excess colors ta1, tb1, the configuration of the partition plate and the storage cases and the like may be appropriately selected.

In addition, the configuration may include a first moving device for moving the above-described partition plate pb and the width direction storage cases pd, pc2, etc., and a second moving device for moving the guide plates gp, gp in the width direction. Based on these configurations, when changing the width dimension of the sheet to be coated, optimum adjustment can be achieved by moving the guide plates gp, gp and the separator plate pb and the storage containers pd, pc2 in the width direction w, whereupon the edge portions of the color curtains ca, cb stabilize and the excess colors ta1, tb1 can be separated and recovered individually.

It should be noted that these moving devices can be formed as a single configuration that integrally moves the guide plates gp, gp and the partition plate pb and the storage cases pd, pc2, etc., and the type of the configuration of the moving devices can be be chosen appropriately.

On the basis of the above-described configurations, due to the fact that the excess colors ta1, tb1 are separated one by one by the center lip N1 and the partition plate pb, etc., and reused and recovered by the special recovery shells cp1, cp2, the amount of ink inevitably becomes mixed, reduced, and a loss of color can be reduced as much as possible.

By the alignment of the edge part of the color curtains ca, cb by the guide plates gp, gp stabilization of the edge portions of the color curtains ca, cb can be achieved beyond, and it can the optimum width of the color curtains ca, cb be adjusted with respect to the width of the web w whereupon a uniform application can be produced accordingly.

Due to the fact that the apparatus includes moving devices for moving each of the guide plates gp, gp and the separator plate pb and the widthwise direction storage containers pd, pc2, the position of the guide plates gp, gp and the separator plates pb, pb and so on can be adjusted be aligned regardless of the width dimension of the web on the width of the web to be coated, stabilization of the edge portions of the color curtains ca, cb can be achieved and the excess colors ta1, tb1 can be separated and recovered individually. Accordingly, a curtain coater that allows the production of a stable two-layer coating with little loss of color can be obtained.

It should be noted that although the above-described embodiment is an example in which the guide plates gp, gp and the partition plates pb, pb and the storage containers pd, pc2, etc. are arranged in two sides of the web w, they are also in only one side of the web w can be arranged, and it goes without saying that even in only one side of the web w, the same effect can be achieved.

Field of industrial use:

As practical examples, the present invention can be applied to application devices for applying color to, for example, calendars, catalogs, pressure-sensitive paper, heat-sensitive paper and photographic film, as well as applicators or the like for application to a magnetic material on one side of automatic platform barrier cards Find.

LIST OF REFERENCES

10 curtain commissioned work

11a, 12a flow channel ca, cb curtain / color curtain gp guide plate (guide means) N medium feeder / paint feeder

N1 Middle lip

N11 tip part of the middle lip

N2 lips from two sides (lips on two sides)

N21 tip part of the lips from two sides (lip tip parts on two sides) pb separation plate (medium release agent / color release agent) pb1 elastic member (medium release agent / color release agent) pb2 separation plate (medium release agent / color release agent) ta, tb coating medium / color ta1, tb1 Excess medium / color w web

Claims

claims

A curtain applicator, wherein by dispensing two types of coating medium, for example paint, from a medium supply device to the top of a moving web

Applying two coating medium layers to the web surface, a two-layered curtain is formed, characterized in that the medium supply device has a central lip which is arranged in the flow channels for the two types of media and has a tip portion which is separated from the tip portions of the two side lips are arranged in the outside of the flow channels for the two types of medium in the outside in the width direction of the web, projecting to the web side, and a convex shaped medium separating means, which abuts the tip portion of the middle lip and the two types of excess medium, for example color, from the Medium-delivery device are delivered, individually separates, covers.

2. curtain applicator unit according to claim 1, characterized in that it further comprises a first moving device for moving the medium-separating agent in the web width direction.

3. Curtain coater according to claim 1 or 2, characterized in that it further comprises a plate-shaped guide means which in the web side of the medium-separating means for aligning the edge part of

Curtain is arranged.

4. curtain applicator according to claim 3, characterized in that it further comprises a second moving device for moving the

Guiding agent in the web width direction comprises.