JP2001087694A - Method and apparatus for preventing turning of color to back side of curtain coater - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form dry edges to both lateral end edge parts of paper. SOLUTION: Bending devices 10a, 10b for bending both lateral end edge parts 3a of raw paper downward are arranged at the vicinal position on the upstream side of the DF head 1 of a curtain coater and constituted by attaching L-shaped dry edge bars 12a, 12b to rotary air cylinders 11a, 11b. The dry edge bars 12a, 12b are revolved downward to be pressed to the raw paper 3 to bend both lateral end edge parts 3a downward and passed through the curtain film 2a of the coating color 2 allowed to flow down from the DF head in the downward bent state. The curtain film 2a is broken by the folds of the raw paper 3 to be prevented from coming into contact with both lateral end edge parts 3a of the raw paper 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a curtain coater for applying a coating color to a base paper manufactured in a paper mill, and a color of the curtain coater for preventing the coating color from wrapping around the back of the paper. The present invention relates to a method and an apparatus for preventing back running.

[0002]

2. Description of the Related Art Paper manufactured in a paper mill is not immediately used as it is, but may be used as a base paper for further processing to obtain a processed paper as a product meeting a required purpose. Many. There are various types of processed paper, one of which is coated paper. Coated paper is manufactured by applying a coating color to the paper surface for the purpose of improving the properties of the paper surface, and there is a coating device as an apparatus thereof.

As one of the coating apparatuses, a so-called curtain coater includes a DF head (liquid supply head) 1 and a coating collar 2 as shown in FIG.
To a curtain film 2a that is uniformly thin in a range wider than the width of the base paper 3.
The base paper 3 wound around the coater roll 4 and traveling slightly upward toward the downstream is coated with the coating color 2.
The coating color 2 is directly applied to the surface of the base paper 3 by passing through the curtain film 2a.

At a position between the DF head 1 and the base paper 3, a shutter pan 5 is disposed so as to be movable in the front-rear direction orthogonal to the flowing direction of the coating color 2. 5 is retracted to retract from the falling position of the coating collar 2, and the shutter pan 5 is advanced to block the falling position of the coating collar 2, that is, the curtain film 2 a of the coating collar 2. By the OFF operation, the supply of the coating color 2 to the base paper 3 is stopped.

Further, the base paper 3 at the upstream position of the curtain film 2a of the coating collar 2, that is, at the upstream position of the DF head 1, is inclined downward in the feed direction of the base paper 3. And a scraper-shaped blade 6 for wind pressure cutoff whose front end (lower end) is brought into contact with the surface of the base paper 3 is arranged. The air is cut off from the surface of the base paper 3 at a position upstream of the DF head 1 so as to be cut off to prevent the curtain film 2a of the coating collar 2 from being disturbed by the wind pressure of the air. .

[0006] Reference numeral 7 denotes a gantry arranged to extend over the entire length of the base paper 3 in the width direction to support the wind pressure blocking blade 6, and 8 denotes a pedestal located downstream of the flow-down position of the coating collar 2. A guide roll 9 for guiding the base paper 3 after the running coating color 2 has been applied, and a color pan 9 for collecting the coating color 2 flowing down from the width end of the base paper 3 during coating.

[0007]

However, in the above-mentioned curtain coater, the curtain film 2a of the coating color 2, which flows down from the DF head 1 to be wider than the width of the base paper 3, is used for the curtain coater.
, The part of the coating collar 2 that flows down the outer sides of the width edges of the base paper 3 at both edges of the base paper 3 is shown in FIG. As shown by the two-dot chain line in
Both ends of the width of the coated paper to be produced come into the back of the base paper 3 and are thickly coated. When the coated paper is wound on a winder, the both ends are thick and the central portion is thickened. However, there is a problem that it is wound in a thin, so-called drum shape.

For this reason, conventionally, the coating color 2 wraps around the back of the base paper 3 and the thickened portions at both edges are cut off with a slitter (cutter).
Alternatively, the coated paper is forcibly wound around the winder at a high nip. However, the slitter may not be able to secure an installation space depending on the arrangement of devices provided around the DF head 1. The method of winding up on a winder with a high nip is to use a color 2 for coating.
In the case where is used, it may not be possible to carry out because the coating color 2 is colored by the pressure at the time of winding on a winder.

[0009] When the coating collar 2 is behind, various equipment in the post-process of the curtain coater is stained by the coating collar 2 which has been covered, but the stain is operated as it is. Cleaning is performed every time the operation of the production line is stopped. However, this cleaning work requires installation of a scaffold, and requires much time and labor.

The inventor of the present invention has conducted various researches to prevent the back of the coating color from going behind, and as a result, when applying the coating color by the curtain coater, the left and right edges of the base paper have been applied to the edges. The present inventors have found that by forming a dry edge (non-coated surface) on which the coating color is not applied, it is possible to prevent the back of the coating color from running behind, and made the present invention.

Accordingly, it is an object of the present invention to provide a method and an apparatus for preventing a color behind of a curtain coater, which can prevent the color behind of a coating color from going behind.

[0012]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a method in which a coating color is caused to flow down from a DF head in the form of a curtain film, and when a base paper passes through the curtain film of the coating color. A method for preventing a color back-around of a curtain coater in which both width edges of the base paper are bent downward at the position immediately before the coating color flow-down position and then the coating color curtain film is passed, The coating color is caused to flow down from the DF head in the form of a curtain film, and the base paper passes through the curtain film of the coating color, so that the coating color is applied to the base paper. In the vicinity of the upstream side of the DF head and above the left and right width edges of the base paper to be coated, folding devices for bending the both width edges of the base paper to be coated downward are respectively installed. A color back around prevention device of a curtain coater having a configuration.

When the folding device is used to bend both width edges of the base paper downward at a position near the upstream side of the curtain film of the coating color flowing down from the DF head, the base paper has both width edges. In a state of being bent downward, it becomes possible to pass through the curtain film of the coating color. At this time, the curtain film of the coating color that flows down is repelled outwardly outside the fold portion of the base paper, and the curtain film breaks, so that both width edge portions of the base paper positioned outside the fold portion are used. , A dry edge (non-coated surface) on which the coating color is not applied is formed.

Further, the folding device has a rotation drive device having a rotation axis substantially parallel to the feed direction of the base paper, and one end is attached to the rotation shaft of the rotation drive device so that the width end edge of the base paper is downward at the tip. An L-shaped dry edge bar to be bent, and the leading edge of the dry edge bar was pressed against the base paper in a plane substantially parallel to the curtain film of the coating color, and the width edge was bent. If it is configured to be able to turn from the state to the state parallel to the base paper, the dry edge bar can be turned downward during use so that the width edge of the base paper can be bent downward by the dry edge bar, and unusable. When in use, the dry edge bar can be pulled out parallel to the base paper to keep it out of the way.

Further, by adopting a configuration in which the tip of the dry edge bar is subjected to ceramic spraying, the resistance of the dry edge bar to friction with paper can be increased.

Further, the folding device is arranged so as to be slidable in the left-right direction so that the position can be adjusted according to the width of the base paper, so that even if the width of the base paper to be coated is changed, the folding device can be used. By adjusting the interval, it is easy to respond.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1 (a) and 1 (b) show an embodiment of a method and an apparatus for preventing a color from lining up in a curtain coater according to the present invention, and are similar to those shown in FIGS. 2 (a) and 2 (b). , D
The curtain film 2 a of the coating color 2 is caused to flow down from the F head 1, and the base paper 3 running while being wound around the coater roll 4 is
In a curtain coater in which the coating color 2 is directly applied to the surface of the base paper 3 by passing the curtain film 2a of the coating color 2, a position near the upstream side of the DF head 1 and A folding device 10 for folding the left and right width edges of the base paper 3 downward by a required width, respectively, above the left and right width edges of the base paper 3 to be coated.
a and 10b are provided.

More specifically, each of the folding devices 10a and 10b is arranged in the feed direction (running direction) of the base paper 3 near the upstream side of the DF head 1 and above the left and right width edges of the base paper 3 to be coated. Shaft 13a, 1 extending substantially parallel to
Rotary air cylinders 11a and 11b as turning drive devices having a rotary shaft 3b are arranged symmetrically on the left and right, and the rotary shafts 13 of the left and right rotary air cylinders 11a and 11b are arranged.
a and 13b, one end of each of dry edge bars 12a and 12b is attached.
The dry edge bars 12a and 12b can be rotated by a and 11b to a position where the dry edge bars 12a and 12b hit the width edge of the base paper 3 and a position where the dry edge bars are retracted upward. That is, the dry edge bar 12a
And 12b are L-shaped, one end of which is attached to the rotary shafts 13a and 13b of the rotary air cylinders 11a and 11b from the tip side, and which is perpendicular to the curtain film 2a from a position near the curtain film 2a of the coating collar 2. The other end (tip) has a length protruding below the width edge of the base paper 3 by a required length so that the rotary air cylinders 11a and 11b are driven to form a dry edge bar. The tip of each of the rotary air cylinders 12a and 12b can be turned in a plane substantially parallel to the curtain film 2a of the coating collar 2. 1 and (b), the respective dry edge bars are pivoted downward (inward), as shown in FIGS. The leading end of 12a and 12b, DF
Curtain film 2a of coating color 2 flowing down from head 1
Before, for example, at a position about 10 mm before,
The right and left width edges 3a of the base paper 3 are pressed obliquely from above to bend the left and right width edges 3a of the base paper 3 downward at a required angle of about 45 to 90 degrees (60 degrees in the figure). So that each rotary air cylinder 1
By turning the left and right dry edge bars 12a and 12b upward (outward) at 1a and 11b, respectively, as shown in FIG.
As shown by a two-dot chain line in (b), the left and right dry edge bars 12a and 12b can be pulled up to a state parallel to the surface of the base paper 3.

Further, similarly to the stand 7 shown in FIG.
Rails 14a and 14b, each extending a required length in the left-right direction, are disposed above the left and right end portions of a frame 7 extending over the entire length of the base paper 3 at the upstream position of the DF head. 14b, on the left and right moving body 1
5a and 15b are slidably mounted in the left and right direction,
The left and right bending devices 10a and 10b are provided on the front surfaces (side surfaces of the DF head 1) of the left and right moving bodies 15a and 15b.
By attaching the rear ends of the rotary air cylinders 11a and 11b respectively, the left and right bending devices 10a and 10b can be connected to the left and right moving bodies 15a and 15b.
b, and slide in the left-right direction to form the dry edge bars 12a and 12b of the folding devices 10a and 10b.
Can be freely adjusted according to the width of the base paper 3 to be coated.

As the dry edge bars 12a and 12b, rods having a diameter of 6 to 8 mm are used. Further, at the contact portions of the dry edge bars 12a and 12b with the base paper, Ceramic spraying is applied to withstand friction with paper.
The left and right moving bodies 15a and 15b are each provided with a pinion 17 to which a handle 16 is coaxially mounted, and the pinion 17 is arranged so as to mesh with a rack 18 disposed on each of the rails 14a and 14b. By doing
By rotating the handle 16, the moving bodies 15a and 15
The position b is freely adjusted and can be fixed by a lock mechanism (not shown). In addition, Figure 2 (b) (b)
The same components as those described above are denoted by the same reference numerals.

When performing a coating operation using a curtain coater, first, the left and right rotary air cylinders 11a and 11a are used.
1b, the left and right dry edge bars 12a and 12b are pulled up, the base paper 3 to be coated is wrapped around from the coater roll 4 to the guide roll 8, and then the left and right moving bodies 15a and 15b are adjusted to the width of the base paper 3. After adjusting the interval between the left and right bending devices 10a and 10b integrally with the 15b, the left and right dry edge bars 12a and 12b are turned downward by the left and right rotary air cylinders 11a and 11b, and the respective dry edge bars 12a and 12b
Thereby, the left and right width edge portions 3a of the base paper 3 are bent downward by a required width at a required angle (for example, 60 degrees).

In this state, the base paper 3 is run by the coater roll 4 and the curtain film 2 a of the coating collar 2 is caused to flow down from the DF head 1, thereby causing the curtain film 2 to flow.
a, the width of the edge 3a of the running base paper 3 is set at a position immediately before the curtain film 2a of the coating collar 2 so that the running base paper 3 passes through the dry edge bar 12a.
a and 12b allows the coating collar 2 to pass through the curtain film 2a of the coating collar 2 with both width edges 3a bent downward. At this time, as shown by the one-dot chain line in FIG.
Since the curtain film 2a of the base paper 3 is repelled outwardly outside the fold portion of the base paper 3 and the curtain film 2a is broken, the width edge portions 3a of the base paper 3 located outside the fold are coated with the coating film. The working collar 2 is not touched, thereby forming a dry edge (non-coating surface) where the coating collar 2 is not applied on both width edges 3 a of the base paper 3.

As described above, since the coating collar 2 does not touch both edge portions 3a of the base paper 3, it is possible to prevent the coating collar 2 from going behind and, therefore, to manufacture the base paper 3. There is no danger that both edges of the coated paper to be coated are thickly coated and wound around a winder in a drum shape, and even when the color-forming coating color 2 is used, the quality of the coated paper to be manufactured is reduced. Can be improved. Further, since various devices used in the post-process of the curtain coater are not contaminated by the coating color 2 behind, it is necessary to perform a cleaning work that requires a lot of labor and time, which has been conventionally performed on the above-described devices. Can be eliminated.

It should be noted that the present invention is not limited to only the above-described embodiment, and that the bending devices 10a and 10b are formed by rotating the L-shaped dry edge bars 12a and 12b by rotary air cylinders 11a and 11b. Although shown as being pressed against the base paper 3, any width edge 3 a of the base paper 3 to be coated can be bent downward immediately before the curtain film 2 a of the coating collar 2. For example, dry edge bars 12a and 12b
May not be L-shaped, and other than the rotary air cylinders 11a and 11b may be used as the turning drive device, and other various changes may be made without departing from the gist of the present invention. Of course, it can be added.

[0026]

As described above, according to the method and the apparatus for preventing the color back of a curtain coater according to the present invention, the coating color flows down from the DF head in the form of a curtain film. When the base paper passes through, the both width edge portions of the base paper are bent downward at the position immediately before the coating color flow-down position, and then the coating color is passed through the curtain film. The coating color is allowed to flow down from the head in the form of a curtain film, and the DF is used in a curtain coater in which the coating color is applied to the base paper by passing the base paper through the curtain film of the coating color. In the vicinity of the upstream side of the head and above the left and right edges of the base paper to be coated, folding devices for bending the width edges of the base paper to be coated downward are respectively installed. Since a device having, DF
The curtain film of the coating color flowing down from the head can be split so as to repel outward outside the fold of the base paper folded by the left and right folding devices,
The curtain film can be prevented from touching both width edges of the base paper located outside the fold, so that a dry edge (uncoated surface) where the coating color is not applied to both width edges of the base paper And the folding device has an excellent effect of preventing the back of the coating collar, and the folding device has a rotating drive device having a rotation axis substantially parallel to the feed direction of the base paper, An L-shaped dry edge bar having one end attached to the rotating shaft of the turning drive device and bending the width edge of the base paper downward at the leading end, and the leading end of the dry edge bar is coated with a coating collar. In a plane that is almost parallel to the curtain film, it can be swung from a state in which the width edge is bent by pressing against the base paper to a state parallel to the base paper. Turn to With the dry edge bar, the width edge of the base paper can be bent downward, and when not in use, the dry edge bar can be pulled out parallel to the base paper surface so that it does not get in the way. By applying ceramic spraying to the part, the resistance of the dry edge bar to friction with the paper can be increased, and the folding device is slidably arranged in the left and right direction, according to the width of the base paper By adopting a configuration in which the position can be adjusted, there is an excellent effect that even when the width of the base paper to be coated is changed, it is possible to adjust the interval of the folding device to easily cope with the change.

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an embodiment of a method and an apparatus for preventing color back of a curtain coater according to the present invention, wherein (a) is a partially cut-away schematic side view, and (b) is an AA arrow of (a). FIG.

FIGS. 2A and 2B schematically show an example of a conventional curtain coater, in which FIG. 2A is a partially cut-away side view, and FIG.
It is an arrow view.

[Explanation of symbols]

Reference Signs List 1 DF head 2 Coating color 2a Curtain film 3 Base paper 3a Width edge 4 Coater roll 10a, 10b Bending device 11a, 11b Rotary air cylinder (rotation drive device) 12a, 12b Dry edge bar 13a, 13b Rotating shaft

Claims (5)

[Claims] 1. A coating color is caused to flow down from a DF head in the form of a curtain film. When the base paper passes through the curtain film of the coating color, the base paper is positioned immediately before the coating color flow-down position. A method for preventing a color from being wrapped around a curtain coater, comprising bending the both width edges downwardly and then passing the curtain film of the coating color. 2. The coating color is caused to flow down from the DF head in the form of a curtain film, and the base paper is passed through the curtain film of the coating color so that the coating color is applied to the base paper. A folding device for bending both width edges of the base paper to be coated downward near the upstream side of the DF head in a curtain coater and above the left and right width edges of the base paper to be coated. A color back-around prevention device for a curtain coater, characterized in that the device has a configuration in which a color is installed. 3. A folding device comprising: a turning drive device having a rotation axis substantially parallel to a feed direction of a base paper; one end attached to the rotation shaft of the turning drive device; An L-shaped dry edge bar to be bent, and the leading edge of the dry edge bar was pressed against the base paper in a plane substantially parallel to the curtain film of the coating color, and the width edge was bent. 3. The apparatus according to claim 2, wherein the apparatus is capable of turning from a state parallel to the base paper. 4. The apparatus according to claim 3, wherein the tip of the dry edge bar is subjected to ceramic spraying. 5. The apparatus according to claim 2, wherein the folding device is arranged so as to be slidable in the left-right direction so that the position can be adjusted according to the width of the base paper.