JP2011104907A - Apparatus for applying water repellent to corrugated fiberboard liner paper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for applying a water repellent to liner paper in manufacturing waterproof corrugated fiberboard, reducing a loss occurring when starting/stopping application of the water repellent to attain high-speed operation, and eliminating a warp caused by the application of the water repellent to substantially dispense with the concentration adjustment of a water repellent liquid according to the size of liner paper and to prevent the water repellent liquid from coming around to the rear side at both edges of the liner paper. <P>SOLUTION: The apparatus includes a press roll (1), a rubber roll (3) and an engraving roll (4) downward from the upper part, and further includes a water repellent liquid receiving pan (5) thereunder, which is arranged such that the engraving roll is rotatable with its lower part submerged in the water repellent liquid (6). The rotation axes of the respective rolls are in such a relative relationship that the rubber roll is fixed, the press roll is movable upward and the engraving roll is movable downward, and three rolls are rotated by passing of liner paper (9) supplied between the press roll and the rubber roll. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to an improvement in an apparatus for applying an emulsion of a water repellent agent to a liner paper in producing water-resistant corrugated paper.

Most of corrugated paper is processed into a box and used, but depending on the use of the box, the surface liner may be required or at least desired to be water resistant. For example, in a cardboard box containing vegetables, at least the inner surface should be water-resistant so that the inner surface is not damaged and the box is not collapsed by moisture emanating from the contents. The water resistance of corrugated paper may be required for both front and back liners, or may be required for only one of the front and back sides. For printing, it is usually not preferable that the corrugated paper has water repellency, and strong water repellency is not preferable even when an adhesive is used at the joint when hitting a box.

To provide water resistance to corrugated paper, a water repellent, often an aqueous emulsion containing a waxy material, is applied to the liner paper. It is preferable from the viewpoint of efficiency that this operation is carried out by being incorporated into the corrugated board manufacturing process. From this point of view, a water repellent coating device is usually incorporated into a corrugated paper manufacturing device.

The water repellent coating device incorporated in the corrugated paper manufacturing apparatus has a configuration as shown in FIG. That is, the tray (5) into which the water repellent liquid (6) that is an aqueous emulsion is placed, the rubber roll (2) that rotates while being partially immersed in the water repellent liquid, and the liner paper (9) are sandwiched to contact the rubber roll. It is the structure which consists of a press roll (1). The press roll is made of steel and is usually plated with chromium to give durability to the surface. The position of the rubber roll is fixed, and only the press roll can move up and down. The water repellent liquid (6) is applied to the water repellent adhering to the rubber roll as the liner paper (9) passes between the press roll (1) and the rubber roll (2). This is done by a mechanism in which the liquid is transferred to the liner paper. When the water repellent is not applied, the press roll is pulled upward and separated from the rubber roll as shown in FIG. At this time, the rubber roll is brought into an idling state by the action of a built-in cam clutch, and is rotated at a low speed by the power of the idling motor.

The conventional water repellent application device having the above-described configuration includes various problems as follows.
1) Along with the recent high-speed production of corrugated paper, a loss occurs when the application of the water repellent starts and ends, and the length reaches 3 to 5 m.
2) On the other hand, in order to ensure the application amount of the water repellent, operation at a very high speed (for example, exceeding a line speed of 220 m / min) is not preferable.
3) When trying to manufacture a single-sided water-resistant corrugated paper, warpage tends to occur. In order to prevent this, there is a case where a wasteful operation of adding water to the liner paper not coated with the water repellent is forced.
4) Since the method of sucking the water repellent liquid differs depending on the size of the liner paper, it is necessary to adjust the density every time the liner paper is replaced.
5) The water repellent liquid wraps around and adheres to both sides of the liner paper. This makes the back side of the liner paper water-repellent and prevents adhesion of a water-based adhesive liquid for adhering to the corrugate.
6) When the liner paper is spliced, depending on the paper splicing direction, a large amount of water repellent liquid may enter the part joined by the double-sided adhesive tape, and the adhesive part may be peeled off. As a solution for the paper splicing trouble, an operation of moving the press roll upward is performed in order to weaken the tension applied to the joining portion for a moment.

The object of the present invention is to solve the above problems found in the production of water-resistant corrugated paper according to the prior art,
1) Minimize losses that occur when starting and stopping water repellent application,
2) To be able to carry out cardboard paper production at a higher speed,
3) Eliminates warping and eliminates the need to add water to liner paper that is not coated with water repellent.
4) Adjust the concentration of the water repellent solution according to the size of the liner paper as much as possible, and
5) At both edges of the liner paper, suppress the wrapping of the water repellent liquid to the back side as much as possible to prevent the adhesive liquid from being repelled and causing poor adhesion,
An object of the present invention is to provide a water repellent coating apparatus capable of performing water repellent processing on liner paper.

As shown in FIG. 3, the water repellent coating apparatus for liner paper according to the present invention is a device for producing water-resistant corrugated paper, and the liner paper is bonded to the corrugated core to produce single-sided corrugated paper. A water repellent application device disposed at a position prior to the device to perform, and / or a position prior to an apparatus for completing another double-sided cardboard by laminating another liner paper with single-sided cardboard,
All have three rolls supported rotatably, and these three rolls exist in the order of press roll (1), rubber roll (3), and engraving roll (4) from the top to the bottom. Further, there is a water repellent liquid receiving tray (5) below, and the lower part of the engraving roll is placed so that it can be immersed in the water repellent liquid (6) and rotated, and the rotating shaft of each roll is a rubber roll. Is fixed, and the press roll is movable upward, the engraving roll is in a relative relationship movable downward, and the liner paper (9) supplied between the press roll and the rubber roll is passed through. It is a water repellent coating device configured to rotate three rolls.

In each part constituting the above-described water repellent coating apparatus, the press roll (1) may be the same as the press roll in the conventional apparatus. In other words, the roll is typically made of steel and has a surface with chrome plating or the like to enhance durability. The rubber roll (3) can also be diverted from the rubber roll (2) that has performed the function of transporting the water repellent liquid to the liner paper in the conventional apparatus. What characterizes the device according to the invention is the engraving roll (4). This is a roll having fine grooves on the surface of a steel roll, and the groove serves to scoop up the water repellent liquid and pass it to the surface of the rubber roll. When this apparatus is not used temporarily, the press roll (1) may be moved upward and separated from the rubber roll (3) as described in the prior art with reference to FIG. The roll is rotated at a low speed by an idling motor, as in the prior art. When this apparatus is not used for a long time, as shown in FIG. 4, the engraving roll (4) is further moved downward and separated from the rubber roll (3). In this case, only the engraving roll is idling rotated.

The main cause of the problems described above in the conventional water repellent coating apparatus is that the water repellent liquid pulled up by being attached to the rubber roll flows down the roll surface as the rubber roll rotates at a relatively high speed. As a result, it was found that, as shown in FIG. 1, “a pool” (7) in which an excessive amount of the water repellent liquid was concentrated was formed. Therefore, in the present invention, the water repellent liquid (6) scooped up by the engraving roll (4) is once transferred to the rubber roll (3) so that the pool of water repellent liquid does not directly contact the liner paper, and then the liner. A mechanism of applying to paper was adopted.

Even in the apparatus of the present invention, the water-repellent liquid pool is generated by operating the corrugated paper manufacturing apparatus at a high speed. However, as described above, the liner paper does not directly contact the pool. The following problems are solved and the following benefits are obtained.
1) Loss generated at the start and stop of application of the water repellent agent is reduced, and can be substantially zero in a preferred implementation.
2) Accordingly, corrugated paper can be manufactured at a higher speed.
3) Since the application amount of the water repellent agent can be suppressed to the minimum necessary, no warping due to the application can be caused, and the wasteful operation of adding water to the liner paper to which the water repellent agent is not applied becomes unnecessary.
4) It is possible to use a water repellent liquid having a relatively high concentration and therefore high viscosity, and to apply it in a reduced amount per unit area on the surface of the liner paper. It is almost unnecessary to adjust the concentration of the water repellent liquid according to the size of the paper.
5) Since it is possible to completely prevent the water repellent liquid from entering the back side at both edges of the liner paper, there is no possibility of causing poor adhesion.
6) Since the above-mentioned trouble of paper splicing is solved, the operation of pulling up the press roll for a moment when the joint passes through the water repellent liquid coating device becomes unnecessary.

When the amount of water repellent applied was reviewed, the amount applied in the prior art was actually excessive in many cases, and the required water resistance of the corrugated paper, specifically the liner paper, was increased. In order to give, it has been found that half the conventional amount, and in some cases less than that, is in time. On the other hand, with regard to the concentration of the water repellent liquid, the use of a water repellent liquid having a high concentration and therefore a high viscosity is affected by the difference in the degree of absorption of the water repellent liquid caused by the difference in the size of the liner paper. It was also found that it can be made smaller. Therefore, as a result of studies aimed at harmonizing and making these findings compatible, the conclusion reached by the inventors was that a highly concentrated water repellent liquid solution was revolutionized per unit surface area of liner paper than before. The solution for applying a small amount is a water repellent application device having three rolls according to the present invention.

The water repellent coating apparatus of the present invention is in principle in common with the gravure offset printing apparatus, as can be easily understood. Here, the selection of the mesh and depth of the grooves of the engraving roll is important. Since the water repellent liquid to be transferred has a high concentration, a normal gravure roll cannot be used as it is as an engraving roll of the apparatus of the present invention, and a suitable operation cannot be expected. It is appropriate to use a mold having a density of 120 mesh and a depth of 75 microns. However, if the groove is too large and deep, excessive water repellent liquid is transferred to the rubber roll, which is not preferable because the water repellent liquid is pooled as in the conventional two-roll apparatus. Should choose the right one.

Although the corrugated paper board manufacturing apparatus provided with the water repellent coating apparatus of the present invention is used, when the water repellent is not applied, the press roll is moved upward to avoid the liner paper from contacting the rubber roll. Driving. In this case, as described above, both the rubber roll and the engraving roll rotate at low speed in the idling state, or the engraving roll is moved downward to cut off the contact with the rubber roll, and only the engraving roll is idled to rotate at low speed. It is good to let them. In order to facilitate such operation, it is preferable to install a cam clutch that can automatically change the relationship between the rolls in the apparatus of the present invention.

Sectional drawing which shows the structure by a prior art of the water repellent liquid application | coating apparatus to the liner paper in a corrugated paper manufacturing apparatus. The figure explaining the idling state when not using the apparatus of FIG. Sectional drawing which showed the structure in the case of this invention of the water repellent liquid application | coating apparatus to the liner paper in a corrugated-cardboard manufacturing apparatus corresponding to FIG. The figure explaining the idling state when not using the apparatus of FIG.

DESCRIPTION OF SYMBOLS 1 Press roll 2,3 Rubber roll 4 Engraving roll 5 Water-repellent liquid receiving tray 6 Water-repellent liquid 7 Water-repellent liquid pool 9 Liner paper

Claims (3)

As shown in FIG. 2, the water repellent coating apparatus for liner paper according to the present invention is a device for producing water-resistant corrugated paper, and the liner paper is bonded to the corrugated core to produce single-sided corrugated paper. A water repellent application device disposed at a position prior to the device to perform, and / or a position prior to an apparatus for completing another double-sided cardboard by laminating another liner paper with single-sided cardboard,
All have three rolls supported rotatably, and these three rolls exist in the order of press roll (1), rubber roll (3), and engraving roll (4) from the top to the bottom. Further, there is a water repellent liquid receiving tray (5) below, and the lower part of the engraving roll is placed so that it can be immersed in the water repellent liquid (6) and rotated, and the rotating shaft of each roll is a rubber roll. Is fixed, and the press roll is movable upward, the engraving roll is in a relative relationship movable downward, and the liner paper (9) supplied between the press roll and the rubber roll is passed through. A water repellent coating apparatus configured to rotate three rolls. The water repellent coating apparatus according to claim 1, wherein the engraving roll (4) has a 125 mesh x 75 micron groove. When the water repellent is not applied, the press roll (1) moves upward and leaves the rubber roll (3), and the pair of the rubber roll (3) and the engraving roll (4) rotates at a low speed in an idling state, or The engraving roll (4) further includes a cam clutch for adjusting a relationship between the rolls so that the engraving roll (4) is rotated at a low speed in an idling state by leaving the rubber roll (3) alone, and further includes an idling motor. Water repellent coating device.

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