JP2011050816A - Edge guide for curtain coater - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the holding power and the stability of an edge guide. <P>SOLUTION: There are disclosed a pair of edge guides 1 for preventing neck-in, each of which is disposed to hold either end part of a paint curtain film flowing down from a guide plate that allows paint ejected from a die to flow downward along the upper face thereof, onto the upper face of a web w running at a high speed, with a liquid lubricant h flowing on the inside face 19 of the edge guide 1 to prevent the flow of the paint curtain from being disturbed by the viscosity resistance of the paint curtain and the inside face 19. A feed port 25 for feeding the liquid lubricant h is disposed in the vicinity of the upper end of the inside face 19, a suction port 26 for sucking the liquid lubricant h is disposed in the vicinity of the lower end of the inside face 19, and a groove 21 for the liquid lubricant h to flow therethrough is disposed in a strip-shaped zone disposed between the feed port 25 and the suction port 26. A slope face 22 is formed on the outside of the groove 21. The end parts on either side of the groove 21 protrude to form a pair of sharp edges. The position of the upper end of the edge guides 1 is made adjustable in the travelling direction of the web, in the width direction of the web, and in the vertical direction, relative to the lower end of the guide plate. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

    The present invention relates to a curtain coater, and more particularly to an edge guide thereof.

    Coated paper such as printing paper, pressure-sensitive paper, and thermal paper used for catalogs and the like is produced by applying a paint onto a web (base material) that is a base paper by a coater and then drying. A machine for applying a paint in this way is called a coating machine. Conventionally, such a coating machine employs a post-metering method in which excessive paint is applied once on the web, and then scraped off with a blade or small-diameter rod or blown off with an air knife. Blade coaters, rod coaters, air knife coaters, etc. were the mainstream. However, in such post-metering coating, the paint penetrates the web a lot due to the hydraulic pressure when applying the paint to the web and the pressing force of the blade, etc., and maintenance due to wear of the blade and rod, etc. There are problems such as high costs.

  Therefore, in recent years, curtain coaters have been widely adopted in which a paint curtain film is ejected from a die (a chamber with a nozzle for producing a paint curtain film) onto a traveling web and applied onto the web. Curtain coaters have long been used in fields such as photographic printing paper, but air entrainment at high speeds of 1000 m / min or more, bubbles mixed in paint, instability of paint curtain film due to insufficient mechanical accuracy, etc. As a result, the coating was not stable and was not used in the paper industry.

  The present applicant has solved these problems, developed curtain coating technology as a stable technology, and has already supplied a large number of curtain coating machines to the whole world. Unlike conventional post metering type coating machines, curtain coating machines are easy to maintain because there are no consumables such as blades and rods, and the coating amount can be easily adjusted with high accuracy, and operability is good. There are features such as high effect of surface property improvement due to contour coating.

  By the way, although the curtain film of the paint falls by its own weight when it leaves the die, a neck-in in which the edge (edge) is pulled inward by the surface tension of the paint and the width of the curtain film becomes narrow is generated. When neck-in occurs, both ends of the curtain film become thicker, and when this is applied to the web as it is, the part becomes thickly coated, which causes poor drying, and the papers adhere to each other during winding. Cause the phenomenon of blocking. Conventionally, the width of the curtain film is made larger than the width of the web so that the curtain film protruding from the web is received by an edge pan provided below the web, and the paint is circulated. However, in a multi-layer curtain coater that uses two or more dies, since mixing of the paint occurs, such a coating method cannot be adopted, and the width of the curtain film is made narrower than the width of the web. The curtain film coating must be applied to the web so as to leave uncoated portions (dry edges) at both ends of the web. Therefore, an edge guide is provided to prevent such neck-in.

  FIG. 8 is a conceptual diagram of such an edge guide. In the figure, A is a die, B is an edge guide, c is a curtain film of paint, and w is a web. The edge guide B is made of metal such as stainless steel and prevents neck-in. However, since the paint has a viscosity, the flow is hindered by the viscosity, and the flow velocity v of the curtain film c of the paint is slow in the vicinity of the edge guide 2 as shown in the figure, and is uniform in the vicinity other than the vicinity of the edge guide B. It is. If the flow rate is small in such a state, the curtain film c of the paint is separated from the edge guide B, and neck-in occurs.

  In order to alleviate such a phenomenon, a lubricating liquid such as water is allowed to flow on the surface of the edge guide 2. 3 and 4 are a perspective view and a partial cross-sectional view of such an edge guide disclosed in Patent Document 1. FIG.

  In FIG. 3, C is an edge guide body, a is a guide surface, b is a slope on both sides of the guide surface a, d is a lubricating liquid supply pipe, e is a lubricating liquid discharge pipe, and f is a separated metal sheet. The guide surface a is an arcuate surface of a porous pipe from which the lubricating liquid begins to ooze. The entire porous pipe is embedded in the groove of the edge guide main body C, and the portion of the arcuate guide surface a looks through the groove. The edge guide main body C has a mountain shape with a guide surface a as a vertex in a plan sectional view.

  The bottom surface of the edge guide main body A has the lowest front end (inner side in the web width direction) and a slope that rises toward the rear end (outer side in the web width direction), and the separation metal sheet f is attached to this bottom surface. Yes. The separation metal sheet f is bent in the vicinity of the front end of the edge guide main body A, the bent portion is the lowest, and the slope f1 rising toward the front (in the web width direction) and toward the rear (outside in the web width direction). And a rising slope f2.

  FIG. 4 is a cross-sectional view in which the vicinity of the lower end of the edge guide is cut by a vertical plane perpendicular to the moving direction of the web w. In FIG. 4, g is a porous pipe, and a part of the pipe is an arcuate guide surface a with a face looking through the groove of the edge guide body C. h is a lubricating liquid, i is a groove provided on the bottom surface of the edge guide body C, and a separation metal sheet f is covered on the bottom surface to form a passage for the mixed liquid of the lubricating liquid h and the paint. This passage communicates with the lubricant discharge pipe e and is sucked by a suction pump (not shown).

  5 and 6 are drawings showing another example of the edge guide disclosed in Patent Document 2. FIG. FIG. 5 is an overall perspective view including an edge guide, and FIG. 6 is a perspective view of the edge guide. In FIG. 5, D is an edge guide, j is a guide plate, and k is a slide edge guide. The paint that has flowed upward from the die flows on the guide plate j, becomes a curtain film c from the downward part of the lower end thereof, falls freely, collides with the web w, and is applied onto the web w. Slide edge guides k are fixed to both sides of the guide plate j, and both ends of the paint flow on the guide plate j are defined by the slide edge guides k.

  The upper end m of the edge guide D is fixed to the lower end of the slide edge guide k. As shown in FIG. 6, an edge guide main body o having a groove portion n through which the lubricating liquid flows extends downward from the upper end portion m. FIG. 7 is an enlarged horizontal sectional view of the groove n. The groove portion n is provided so as to sandwich the curtain film c from both sides, and a number of grooves and peaks are continuously provided in a zigzag shape as shown in the figure. The width of the groove (or peak) is 0.5 mm, and the angle at the bottom of the groove is 90 °, so the depth is 0.25 mm. The entire width of the groove part n is 10 to 12 mm.

  At the lower end of the groove portion n of the edge guide main body o, a suction port for sucking the mixed liquid of the lubricating liquid and the paint is provided. The opening height of the suction port is 0.1 to 1 mm. The lower end of the edge guide main body o is in light contact with the web w, and is a slope that rises from the contact point toward the outside in the web width direction.

Special table 2008-529753 Special table 2005-512767

The invention disclosed in Patent Document 1 described with reference to FIGS. 3 and 4 has the following problems.
a. The lubricating liquid supplied to the inside of the porous pipe g oozes out through the porous material and flows down along the guide surface a. However, the flow rate of the lubricating liquid is large, and the porous material is easily clogged as time passes. Since the liquid does not ooze out, it must be replaced frequently. Therefore, it takes time for maintenance and costs increase.
b. As shown in FIG. 4, the separation metal sheet f attached to the bottom surface of the edge guide main body C has a slope f <b> 1 rising toward the front (in the web width direction), so the curtain film c is sloped. Neck-in p occurs while falling from the upper end of f1 to the web w. Therefore, both end portions of the paint on the web w are thickly coated, resulting in poor drying of the portions.
c. At the upper end of the inclined surface f1, a part of the coating material of the curtain film c wraps around as shown in FIG. 4, and it splashes and scatters and soils the dry edge of the web w.
d. Since the web w travels at a high speed, air turbulence occurs as shown in FIG. 4, and this portion becomes an unstable region of air pressure. Therefore, both ends of the web w flutter, and the end of the paint on the web w bends like a snake.

The invention disclosed in Patent Document 2 described with reference to FIGS. 5 to 7 has the following problems.
A. Since the edge guide D is fixed to the slide edge guide k, there are the following problems.
a. Since the position of the edge guide body o cannot be finely adjusted in the traveling direction of the web w, the tipot phenomenon described later with reference to the drawings cannot be handled. The tipot phenomenon refers to a phenomenon in which the curtain film c slightly turns upstream when the flow of the paint leaves the guide plate j and flows down as the curtain film c.
b. Since the position of the edge guide body o cannot be finely adjusted in the vertical direction, the relative position between the lower end of the edge guide body o and the pass line of the web w cannot be finely adjusted. Therefore, flapping at both ends of the web w cannot be suppressed.
c. Since the position in the width direction of the web w of the edge guide D cannot be adjusted, the coating width cannot be adjusted.
B. Since the lower end of the edge guide body o is a slope that rises from the inner side to the outer side in the width direction of the web w, as described with reference to FIG. 4, it is between the bottom surface of the edge guide body o and the upper surface of the web w. Air turbulence occurs in the area and the web w flutters.
C. Since the entire width of the groove portion n of the edge guide body o is as wide as 10 to 12 mm, both ends of the curtain film c are groove portions when the position of the curtain film c in the moving direction of the web w is swayed by the influence of tipping phenomenon or wind. Although it easily moves within the entire width of n, the original flow trace dries and adheres to the top of the peak shown in FIG. 7, causing the edge disturbance of the curtain film c.

  The present invention has been devised in view of such a problem of the prior art, the edge of the curtain film of the paint is stably held along the groove of the edge guide, and does not take the trouble of maintenance, An object of the present invention is to provide an edge guide for a curtain coater that can cope with the tipot phenomenon without flapping at both ends of the web w during high-speed running.

    In order to achieve the above object, an edge guide for a curtain coater according to claim 1, wherein the guide plate has an inclined portion for allowing paint sprayed from one or more dies to flow along the upper surface and a downwardly directed guide portion at the lower end of the inclined portion. The curtain coater is provided so as to sandwich both ends of the curtain film of the paint that flows downward to apply the paint on the upper surface of the web traveling at high speed from the guide plate. A pair of edge guides for preventing neck-in that flow and reduce the blockage of the flow due to the viscosity between the curtain film of the paint and the inner surface by the lubricating liquid, near the upper end of the inner surface The lubricant supply port is provided near the lower end of the inner surface, and the suction port for the lubricant and paint mixed therewith is provided. In the area, there is a groove through which the lubricating liquid flows, the outer surface of the groove is inclined, and is a mountain shape with the groove at the top in a plan view, and the ends on both sides of the groove are raised and sharp. The edge guide has an upper edge, and the position of the upper end of the edge guide can be adjusted in the web traveling direction, the web width direction, and the vertical direction with respect to the lower end of the guide portion of the guide plate.

  Further, the edge guide of the curtain coater according to claim 2 is provided so as to sandwich both ends of the paint curtain which is ejected from the die and flows downward to apply the paint to the upper surface of the web running at high speed. A pair of edge guides for preventing neck-in, wherein the lubricating liquid flows to the surface and reduces obstruction of the flow due to the viscosity between the paint curtain and the inner surface. A lubricating liquid supply port is provided near the upper end, a lubricating liquid and a paint inlet mixed therewith are provided near the lower end of the inner surface, and a belt-like region between the lubricating liquid supply port and the suction port on the inner surface is provided. Is provided with a groove through which the lubricating liquid flows, and the outside of the groove has an inclined surface, and is a mountain shape with the groove at the top in a plan view, and the edges on both sides of the groove are raised and sharp edges The above edge The upper end of the de for coating material ejection opening of the die, located in the web width direction and the vertical direction is adjustable.

  The width of the groove is preferably 2 to 4 mm.

  The lower surface of the edge guide is parallel to the paper surface, and its height can be adjusted to be slightly higher, the same or slightly lower than the running web. Is preferred.

The operation and effect of the invention of claim 1 are as follows.
a. Since the upper end of the edge guide can be finely adjusted in the web traveling direction with respect to the lower end of the guide portion of the guide plate, it is possible to cope with the tipot phenomenon.
b. Since the upper edge of the edge guide can be finely adjusted in the vertical direction with respect to the lower edge of the guide portion of the guide plate, fluttering of both ends of the web can be prevented if the lower surface of the edge guide is parallel to the paper surface. it can.
c. The edges on both sides of the edge guide groove are raised and sharp edges, and the outside of the groove is an inclined surface, so even if the paint curtain film shakes, the edge of the paint curtain film may come off the groove. Absent.
d. Therefore, stable coating is possible, high-speed coating is possible, and defective products caused by blocking due to poor drying due to thick coating at both ends of the coating are eliminated, and the quality of the coated paper Will improve.

  The operation and effect of the invention described in claim 2 are as follows. Other than that, the description is omitted.

It is drawing of the edge guide of the curtain coater of this invention, (A) is the front view seen from the inner side, (B) is a side view. (A) is AA sectional drawing of the edge guide of a curtain coater, (B) is a top view. It is a perspective view of the edge guide disclosed by patent document 1. FIG. It is a fragmentary sectional view of the edge guide indicated by patent documents 1. It is a whole perspective view containing the edge guide disclosed by patent document 2. FIG. It is a perspective view of the edge guide disclosed by patent document 2. FIG. It is an expanded horizontal sectional view of the groove part n of the edge guide disclosed by patent document 2. FIG. It is a conceptual diagram of the conventional edge guide. (A) is a figure which shows the state which cut | disconnected the guide plate inside the edge guide attachment part, (B) is a side view which shows the state which attached the edge guide to the guide plate. It is drawing which shows the state which attached the edge guide to die | dye, (A) is a single layer coating, (B) is a two-layer coating with one die, (C) is a two-layer coating with two dies. Each is shown. (A) shows a structure in which three dies are arranged side by side on a guide plate and a flow of three layers of paint is formed on the guide plate, and then applied as a curtain film of three layers of paint on the web; (B) shows three layers of paint flow on the guide plate by combining three dies for jetting paint from the bottom to the top, and then coating on the web as a three-layer paint curtain. Show. It is a horizontal sectional view of an edge guide, and shows the relation between a paint curtain and an edge guide.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a drawing of an edge guide of a curtain coater of the present invention, (A) is a front view seen from the inside, and (B) is a side view. FIG. 2A is a cross-sectional view taken along the line AA of the edge guide of the curtain coater, and FIG. 2B is a plan view. FIG. 9 is a view showing a state where the edge guide is attached to the guide plate, and FIG. 9A is a view showing a state where the guide plate is cut inside the edge guide attaching portion, and is an explanatory view of the tipot phenomenon. FIG. 9B is a side view showing a state in which the edge guide is attached to the guide plate. FIG. 10 is a diagram showing a state in which the edge guide is attached to the die. FIG. 10 (A) is a single layer coating, FIG. 10 (B) is a two-layer coating with one die, and FIG. The two-layer coating with one die is shown respectively. FIG. 11 is a drawing showing multilayer coating using a guide plate. FIG. 11A shows a state in which three dies are arranged side by side on the guide plate to form a three-layer paint flow on the guide plate. FIG. 11 (B) shows a flow of three layers of paint on a guide plate by combining three dies for jetting paint from the bottom to the top as a curtain film of a layer of paint. Is formed on a web as a three-layer paint curtain. FIG. 12 is a horizontal sectional view of the edge guide and shows the relationship between the paint curtain and the edge guide.

  First, the location where the edge guide of the curtain coater of the present invention is used will be described with reference to FIGS. In FIG. 10A, 1 is an edge guide, 2 is a die, w is a web, c is a curtain film, and the web w runs in the direction of the arrow. The edge guide 1 is provided so as to sandwich both end portions of the curtain film c. In FIG. 10B, reference numeral 3 denotes a die, the die 3 is an integration of two dies, and the curtain film c is a paint film having two layers. Except for the die, the description is omitted because it is the same as FIG. In FIG. 10C, two-layer coating is realized by using two dies.

  In FIG. 11A, 5 is a guide plate. The guide plate 5 has a slope and a downwardly directed curtain guide portion at the bottom of the slope, and the coatings sequentially ejected from the three dies 2 toward the slope are sequentially stacked as they move on the slope. Thus, three paint layers are formed and transferred from the downward curtain guide portion of the lower end portion of the inclined surface onto the web w surface as a three-layer curtain film c. Other than that, the description is omitted because it is the same as FIG. In FIG. 11 (B), reference numeral 4 denotes a die, which is an integrated three dies that eject the paint obliquely upward, and paints that are sequentially ejected from the three dies toward the slope, As it moves on the slope of the guide plate 5, it is laminated in order to form a three-layer paint layer, and moves from the downward curtain guide portion on the lower end of the slope to the web w surface as a three-layer curtain film c. Let

  Next, the structure of the edge guide 1 is demonstrated using FIG. 1 and FIG. 1 and 2, reference numeral 1 denotes an edge guide. The front view has a rectangular shape, and an inner surface 19 is provided with a protrusion 20 that extends vertically with a groove 21 as a center. The upper surface 1a of the edge guide 1 has an inclined surface with the inside as a vertex as shown in FIG. The lower surface 1b is parallel to the paper surface. As shown in FIG. 2A, the protrusion 20 is provided with a groove 21 extending perpendicularly to the center of the protrusion 20, and both sides of the protrusion 20 are inclined surfaces 22, each having a mountain shape with the groove 21 as a vertex. Yes. The outer surface 23 of the inclined surface 22 is a vertical surface that intersects at right angles to the traveling direction of the web w. Instead of such a protrusion, the entire inner surface 19 may have a mountain shape with the groove 21 as a vertex. Here, t is a paint applied to the web w.

  The ends on both sides of the groove 21 are raised to form sharp edges 21a. The width of the groove 21 is 2 to 4 mm. The shape of the groove 21 is shown as an arc shape in FIG. 2A, but it may be a triangle having the center of the groove as a vertex. Although the number of grooves is shown as one, a plurality of grooves may be used. The angle α of the slope 22 is preferably 15 to 90 °.

  h is a lubricating liquid such as water, and 24 is a connection port of the lubricating liquid h, which is connected to a lubricating liquid supply pipe (not shown). Reference numeral 24a denotes a lubricating liquid passage communicating with the lubricating liquid connection port 24. The upper portion is bent in a U shape and connected to the upper end of the groove 21 to form a lubricating liquid supply port 25. h flows into the groove 21. As an example, the flow rate of a lubricating liquid such as water is about 10 to 100 cc / min per edge guide. The viscosity of the paint is 100 to 2000 mPa-s (Brookfield viscosity).

  The lower end of the groove 21 is connected to the suction port 26 for the mixed liquid of the lubricating liquid h and the paint. The height of the suction port 26 is 0.5 to 1.5 mm, and the width is 3 to 5 mm. The interior of the suction port 26 is a suction chamber 26a as shown in FIG. The bottom plate 1a of the suction chamber 26a extends forward. The bottom surface of the bottom plate 1a is parallel to the paper surface. Reference numeral 27 denotes a suction connection port, which is connected to a vacuum suction pump (not shown) via a communication pipe (not shown). The degree of vacuum in the suction chamber 26a is about -90 to -98 kPa. q is the exhaust.

  Next, an attachment device for attaching the edge guide 1 to the guide plate 5 will be described with reference to FIG. As shown in FIG. 9B, reference numeral 8 denotes an edge guide mounting device. Reference numeral 9 denotes a bracket attached to the back surface of the guide plate 5. Reference numeral 10 denotes a screw rod, and a screw and a keyway are cut at the base end portion. The base end portion of the screw rod 10 is slidably inserted into a round hole provided below the bracket 9, and a key is fixed to the round hole and can slide with the key groove of the screw rod 10. It has become. Therefore, the screw rod 10 slides in the round hole of the bracket 9 without rotating. The position of the screw rod 10 is fixed by tightening the bracket 9 so as to sandwich the lower end of the bracket 9 with two nuts (not shown) screwed to the base end portion of the screw rod 10. The position of the screw rod 10 in the web w width direction can be adjusted by loosening the two nuts screwed to the base end portion of the screw rod 10, so that the position of the edge guide 1 in the web w width direction can be adjusted. Can be adjusted.

  An attachment metal 11 is fixed to the tip of the screw rod 10. Two elongated holes in the vertical direction are formed below the mounting hardware 11. Reference numeral 12 denotes a metal object having one end face which is a horizontal plane and the other end face which is bent in a U-shape. Two screw holes are formed at both ends, and the bolt is screwed. It is worn. Reference numeral 13 denotes a bracket attached horizontally to the edge guide 1. Two lateral long holes are formed at the tip of the bracket 13. The four bolts screwed to the U-shaped metal piece 12 penetrate the inside of the above-mentioned vertical hole and the horizontal long hole, and by tightening the bolt, the character to the mounting metal 11 is obtained. The bracket 12 can be fixed to the bracket-shaped hardware 12 or the U-shaped hardware 12 and the bolts are loosened, whereby the edge guide 1 is moved in the web traveling direction and up and down with respect to the lower end of the guide portion of the guide plate 5. The position can be adjusted in the direction.

  Next, an embodiment of the invention described in claim 2 will be described. In this embodiment, the edge guide 1 is directly attached to the die 2 or the die 3 as shown in FIG. Since the tipot phenomenon does not occur in the curtain film c flowing out from the die 2 or the die 3, it is not necessary to adjust the position of the edge guide 1 in the web traveling direction. This will be described with reference to FIG. The invention of claim 2 is different from FIG. 9 in that a. The bracket 9 is attached to the die 2 or die 3 instead of the guide plate 5, and b. The U-shaped hardware 12 and the bracket 13 are integrated. Accordingly, the position of the upper end of the edge guide 1 can only be adjusted in the web width direction and the vertical direction with respect to the paint outlet of the die 2, and the position adjustment in the web w traveling direction cannot be performed.

Next, the effect of this embodiment is demonstrated.
a. Since the upper end of the edge guide 1 can be finely adjusted in the advancing direction of the web w with respect to the lower end of the guide portion of the guide plate 5, it is possible to cope with the tipot phenomenon. Here, the tipot phenomenon is a phenomenon in which the curtain film c slightly turns upstream when the flow of the paint 6 moves away from the lower end of the guide plate 5 and flows down as the curtain film c. That is, the flow of the coating 6 is fast on the guide plate 5 due to the viscosity of the coating, and the upper surface in contact with air is fast, and the lower surface in contact with the surface of the guide plate 5 is slow. When the curtain film c flows down, the curtain film c slightly wraps upstream as shown in FIG. 9A due to the law of inertia. The dimension that the curtain film c slightly wraps around the upstream side due to the tipot phenomenon changes depending on the viscosity of the paint, the flow rate of the paint, etc. Therefore, the edge guide 1 can be finely adjusted in the traveling direction of the web w. is important.

  b. Since the upper end of the edge guide 1 can be finely adjusted in the vertical direction with respect to the lower end of the guide portion of the guide plate 5, if the lower surface 1b of the edge guide 1 is parallel to the paper surface, the web w will flutter at both ends. Can be prevented. That is, as shown in FIG. 9B, the gap u between the lower surface of the edge guide 1 and the upper surface of the web w can be changed between −1 and +2 mm. Here, -1 mm means a state in which both end portions of the web w are pushed down by 1 mm. It is clear that flapping at both ends of the web w can be prevented by pushing down in this way. When the gap u is + and is a small value, when the air accompanying the web w flows through a narrow gap between the lower surface of the edge guide 1 and the upper surface of the web w, the static pressure is reduced by Bernoulli's theorem. Since both ends of the web w are lifted, flapping of both ends of the web w can also be prevented.

  c. The end portions 21a on both sides of the groove 21 of the edge guide 1 are raised and have sharp edges, and the outer side of the groove is an inclined surface 22, so that the paint curtain film c is shaken or the curtain film c is caused by the tipot phenomenon. However, the edge of the curtain film c does not come off the groove even if the web w is shifted in the traveling direction of the web w. This will be described with reference to FIG. As shown in the figure, when the lubricating liquid h is caused to flow into the groove 21 of the edge guide 1, the flow of the lubricating liquid h rises to the left and right by the action of the end portions 21a on both sides of the groove 21 having a sharp edge and the surface tension. It flows in the state. Therefore, even if the curtain film c is swung larger than the width of the groove 21 in the traveling direction of the web w, the coupling between the lubricating liquid h and the curtain film c is not broken. Since both sides of the groove 21 are inclined surfaces 22, when the curtain film c is separated from the groove 21 and the edge of the curtain film c comes into contact with the inclined surface 22, the curtain film c is stretched in the width direction. It is pulled back by the surface tension of the curtain film c and immediately returns to the groove 21.

  d. For the reasons described above, the edge guide of the curtain coater of the present invention enables stable coating and coating at a higher speed, and blocking due to poor drying due to thick coating at both ends of the coating. The quality of coated paper is improved without waking up.

  The present invention is not limited to the embodiments described above, and various modifications can be made without departing from the scope of the invention.

1 …… Edge guide,
2 ... Die,
5 …… Guide plate,
19 …… The inner surface of the edge guide,
21 …… Groove,
22 …… Inclined surfaces on both sides of the groove,
25 ... Lubricant supply port,
26 …… Lubricant inlet,
c: Paint curtain film,
h …… Lubricant,
w …… Web.

Claims (4)

    In a curtain coater provided with a guide plate having an inclined portion for allowing paint sprayed from one or more dies to flow down along the upper surface and a downward guide portion at the lower end of the inclined portion, the upper surface of the web running at high speed from the guide plate It is provided so as to sandwich both ends of the paint curtain that flows down to apply the paint on the inside, and the lubricating liquid flows on the inner surface, and the lubricating liquid impedes the flow due to the viscosity between the paint curtain and the inner surface. It is a pair of edge guides for preventing neck-in, which is a lubricant supply port near the upper end of the inner surface, and a lubricant and paint mixed with it near the lower end of the inner surface. A suction port is provided, and a groove through which the lubricant flows is provided in a belt-like region between the lubricant supply port and the suction port on the inner surface, and the outside of the groove is an inclined surface. In the plan view, it has a mountain shape with the groove at the apex, the ends on both sides of the groove are raised and sharp edges, and the upper end of the edge guide is the web progression relative to the lower end of the guide portion of the guide plate An edge guide for a curtain coater characterized in that the position can be adjusted in the direction, the web width direction and the vertical direction.     It is provided so as to sandwich the both ends of the paint curtain that sprays from the die and flows downward to apply the paint to the upper surface of the web running at high speed, and the lubricating liquid flows on the inner surface, and the lubricating liquid A pair of edge guides for neck-in prevention designed to reduce the flow hindrance due to the viscosity with the inner surface, the lubricant supply port near the upper end of the inner surface, and the lower end of the inner surface A suction port for the lubricating liquid and the paint mixed therewith is provided in the vicinity, and a groove for flowing the lubricating liquid is provided in a belt-like region between the supply port for the lubricating liquid and the suction port on the inner surface. The outer side is an inclined surface, and is a chevron with a groove at the top in a plan view, the ends on both sides of the groove are raised and sharp edges, and the upper end of the edge guide is the top of the die Web width for paint spout And a curtain coater edge guide vertically position, characterized in that it is adjustable.     The edge guide of the curtain coater according to claim 1 or 2, wherein the optimum width of the groove is 2 to 4 mm.     The lower surface of the edge guide is parallel to the paper surface, and its height can be adjusted to be slightly higher, the same or slightly lower than the height of the running web. An edge guide for a curtain coater according to any one of claims 1 to 3.

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