JP5478315B2 - Paper dust removing device and paper dust removing method for tissue paper coating chemicals - Google Patents

Description

  The present invention relates to a method and an apparatus for removing paper dust from a coated chemical solution in the manufacturing process of the chemical-coated tissue paper.

A tissue paper called a lotion type, in which a chemical such as a moisturizing agent or a softening agent is applied to the surface, is well known (Patent Document 1).
In producing such chemical-coated tissue paper, moisturizers mainly composed of softeners and glycerin are expensive. Therefore, disposal should be minimized in consideration of the impact on the environment. In order to make the use efficiency as high as possible, it is common to circulate and use a so-called chemical solution, in which the excess chemical solution that has not been applied is recovered and used again in the application process.

  However, the paper powder separated from or scattered from the paper sheet is mixed in the chemicals collected from the coating process, and the amount of paper powder in the coated drug increases with the lapse of coating time, increasing the viscosity of the drug. As a result, there is a problem that the coating amount increases and the variation in the coating amount in the coating width direction and the flow direction becomes large.

Japanese Patent Laid-Open No. 4-9121 JP 2008-264564 A

  Therefore, the main problem of the present invention is to efficiently remove paper dust mixed in the chemical solution in the manufacturing process of the chemical-coated tissue paper, and as a result, stabilize the viscosity of the coating solution and suppress variation in the coating amount. It is to provide an apparatus and method that can.

The present invention that has solved the above problems is as follows.
<Invention of Claim 1>
The tissue paper sheet running between the impression cylinder and the plate cylinder is a facility configured to apply a chemical solution on the plate surface of the plate cylinder by a flexographic printing method or a gravure printing method,
A brush is provided so as to face and contact the plate surface of the plate cylinder, and the chemical solution containing paper dust attached to the plate surface of the plate cylinder is removed from the plate surface of the plate cylinder by the brush bristles. Paper dust removing device for tissue paper coating chemicals.

(Function and effect)
When applying chemicals such as moisturizers and / or softeners to tissue paper, roll transfer methods such as flexographic printing and gravure printing, and non-contact coating methods such as spray coating and inkjet printing Alternatively, any known coating method such as dipping can be used.
In these chemical solution application forms, except for non-contact type chemical solution application methods such as a spray method that can completely seal the applied chemical solution to the outside, the paper powder that detaches from the paper sheet and scatters is contained in the applied chemical solution. There is a risk of contamination.

  In particular, in roll transfer methods such as flexographic printing and gravure printing, the plate comes into direct contact with the surface of the tissue paper sheet. It may return to the coating solution tank via the surface.

Chemical liquids are not cheap, and even if waste liquids are used, there is an environmental impact due to waste liquid treatment. Therefore, it is desirable to recover the uncoated chemical solution and apply it again.
However, when the tissue paper is running, the scattered paper powder is mixed into the applied chemical due to rubbing with the roll, etc. If the recovered unapplied chemical is continuously reused, the paper powder content gradually increases. In addition, there is a problem that the viscosity of the chemical solution is increased, the coating amount on the tissue paper is increased, and the coating amount varies in the coating width direction and the flow direction.

On the other hand, when the chemical solution is applied by an immersion method or spray coating, variations in the coating amount are likely to occur in the width direction and the flow direction. In this respect, the flexographic printing method and the gravure printing method have an advantage that the coating amount can be stably applied in the width direction and the flow direction.
However, in the flexographic printing method, paper dust adheres to the surface of the plate convex portion of the plate cylinder which receives the chemical solution from the anilox roll and is applied to the sheet, or the paper concave portion is clogged with paper dust. In this way, the paper powder clogs the plate itself, resulting in coating unevenness that partially affects the quality.

On the other hand, the paper powder is transferred from the plate surface to the anilox roll surface, and then transferred from the anilox roll surface to the chemical solution in the chamber, or the paper powder is transferred to the dip roll surface and finally the paper powder moves to the chemical solution tank. To do.
Then, as the concentration of paper powder in the chemical increases, the viscosity of the applied chemical increases, and the amount of application from the plate to the paper tends to increase as the application time elapses. Further, when the viscosity of the chemical solution increases, the chemical solution is less likely to be transferred uniformly between the rolls in the width direction, and thus the variation in the coating amount in the width direction increases.

  Similarly in the gravure printing method, paper powder is clogged in the concave portion of the plate cylinder which receives the chemical solution and is applied to the sheet, and as a result, the viscosity of the chemical solution is increased. Variations in the coating amount will occur.

  In the present invention, in the plate cylinder to which the chemical solution is finally transferred and applied to the sheet, a brush is provided so as to face and contact the plate cylinder, and the chemical solution containing paper powder is removed from the plate cylinder by the brush bristles. Therefore, it is possible to prevent clogging of paper powder in the chemical solution on the plate surface of the plate cylinder. As a result, it is possible to eliminate the risk of the application amount increasing with time and causing variations in the application amount in the flow direction and the width direction.

<Invention of Claim 2>
2. The paper dust removing device for a tissue paper coating chemical solution according to claim 1, wherein the sheet is configured to run vertically between the impression cylinder and the plate cylinder, and the brush is provided below the plate cylinder.

(Function and effect)
Since the brush is provided under the plate cylinder to remove the paper powder-containing liquid from the plate cylinder, the removed paper powder-containing liquid can be prevented from rolling up and scattering, and thus can be prevented from adhering to the sheet.

<Invention of Claim 3>
The paper dust removing device for a tissue paper coating chemical solution according to claim 2, wherein the brush is provided below the plate cylinder, and a chemical liquid collection receptacle is provided below the brush.

(Function and effect)
If a chemical solution collection receptacle is provided below the brush, the chemical solution can be prevented from dripping and can be collected.

<Invention of Claim 4>
4. The paper dust removing device for tissue paper coating chemical solution according to claim 3, further comprising air jetting means for jetting air toward the brush to separate the paper dust from the brush bristles.

(Function and effect)
By providing air jetting means for jetting air toward the brush and separating the paper dust from the brush hair, the paper dust can be separated from the brush hair by blowing off the liquid containing the paper dust. As a result, it is possible to prevent the accumulation or clogging of paper dust in the chemicals in the plate cylinder.

<Invention of Claim 5>
4. The tissue paper coating chemical solution according to claim 3, further comprising a paper powder separating means for separating paper powder from the chemical liquid collected in the chemical liquid receiving container, and a chemical liquid returning means for reusing the chemical liquid from which the paper powder has been separated. Paper dust removal device.

(Function and effect)
Furthermore, by having a paper powder separating means for separating the paper powder from the chemical liquid collected in the chemical liquid collection receptacle and a chemical liquid returning means for reusing the chemical liquid from which the paper powder has been separated, the separation chemical liquid can be reused. It becomes possible.

<Invention of Claim 6>
Using the paper dust removing device for tissue paper coating chemical solution according to any one of the preceding claims, the paper powder in the chemical fluid adhering to the brush bristles of a brush is removed. Paper dust removal method.

  According to the present invention, in the plate cylinder to which the chemical solution is finally transferred and applied to the sheet, the brush is provided so as to oppose and contact the plate surface of the plate cylinder, and the chemical solution containing the paper powder is transferred by the brush bristles to the plate surface of the plate cylinder. Therefore, it is possible to prevent clogging of the paper powder in the chemical solution on the plate surface of the plate cylinder. In addition, as a result of efficiently removing paper dust mixed in the chemical liquid, the viscosity of the coating liquid can be stabilized and variation in the coating amount can be suppressed.

It is a flowchart which shows an example of the paper dust removal apparatus and piping of a chemical | medical solution which concern on this invention. It is a cross-sectional view in the width direction of the upper running surface pressing part of the filter belt and the mesh belt. It is a top view which shows typically arrangement | positioning of the filter push-down roll on the upper running surface of a filter belt. It is principal part explanatory drawing of FIG. It is a front view of a brush roll. It is a front view which shows the brush roll of another example partially. It is a flowchart which shows another example of the paper dust removal apparatus and piping of the chemical | medical solution which concern on this invention. It is an outline explanatory view of an example of chemical solution application with a ply machine. It is the schematic which shows an example of the apparatus which concerns on flexo application | coating. It is the schematic which shows an example of the apparatus which concerns on gravure coating.

(Example of chemical solution coated tissue manufacturing process)
In FIG. 8, the example of the manufacturing process of the tissue paper obtained by apply | coating a chemical | medical solution in a ply machine is shown.
The base paper produced by the paper machine is creped as a continuous sheet, calendered, and wound up to form a primary raw roll JR (generally also called jumbo roll).

  The continuous sheets S <b> 11 and S <b> 12 are laminated by a laminating roller 51 to form two plies, and are calendered by a ply machine calender 52 as needed, and sent to the chemical solution applying means 53. It is preferable that the chemical solution is applied only from one side of each ply, and the surfaces to which the chemical solution is not applied are overlapped, and the ply is fixed later. Any known coating method such as flexographic coating or gravure coating can be used as the chemical coating method.

  It is preferable that the two-ply continuous sheet coated with the chemical solution is provided to the contact embossing roller 54B and the roller roll 54A and fixed by performing a contact embossing (knurling) process. The contact embossing is preferably applied uniformly in the vertical direction with a width of 1 to 10 mm at positions of 1/10 to 1/20 with respect to the paper width from both sides. Any of the known methods, such as fixing the ply with an adhesive, may be used. However, when using an adhesive, there is a problem that the touch tends to become hard, and it is easy to peel off when applying a chemical solution. It can be said that the use of embossing is more preferable.

A continuous sheet of 2 plies with contact embossing is directly cut into a product size after being subjected to folding processing by being directly applied to a rotary interfolder or the like, or after being cut into a product width by a slitter 55, The winding material is taken up by the winding drum 56 as a secondary roll roll R, folded, and stored in a paper box.
In addition, although the structure which provides a chemical | medical solution before contact embossing is taken in this form, it is good also as a structure which provides a chemical | medical solution after contact embossing.

  The secondary raw roll described above is subjected to a folding process particularly in tissue paper products. As the folding process, a known method such as a rotary interfolder or a multi-stand interfolder can be used, but it is more preferable to use a multi-stand interfolder with high productivity.

  In addition, although the manufacturing process of the tissue paper of 2 plies was illustrated, the chemical | medical solution supplied from the paper dust removal apparatus in the chemical | medical agent based on this invention can be used effectively also in another manufacturing process, Said manufacture It is not limited to use in the process.

(Chemical solution application process-example of flexo application)
Any known coating means can be used as the chemical solution coating step, but it is preferable to use a printing method such as gravure coating or flexographic coating that uniformly applies the chemical solution to the entire coated surface.

  Of the chemical solution application process, it is more preferable to use a flexo coater equipped with a doctor chamber 61, because the chemical solution can be supplied in a stable application amount.

  8 and 9 show an example of a doctor chamber type in the flexographic printing method. As shown in FIG. 9, the chemical solution application unit 53A in the form of one of the doctor chambers has a doctor chamber 61A in which a chemical solution is placed facing a rotatable anilox roll 63A, and the anilox from the doctor chamber 61A. The chemical solution is delivered to the roll 63A. Further, a plate cylinder roll 64A that is in contact with the anilox roll 63A and is also in contact with one surface of the laminated continuous sheet S2 is rotatably installed, and a chemical solution is delivered from the anilox roll 63A to the plate cylinder roll 64A. Furthermore, a chemical solution is applied from the plate cylinder roll 64A to the laminated continuous sheet S2 while applying pressure to the laminated continuous sheet S2 with the impression cylinder roll 65A facing the plate cylinder roll 64A across the laminated continuous sheet S2. It is like that.

  And in this form, this chemical | medical solution application part 53A is located in the surface side of lamination | stacking continuous sheet S2 which opposes the roller 54A of the contact embossing means 54, and opposes the above-mentioned winding drum 56A. A supply pump (not shown) for applying a chemical solution to the doctor chamber 61A and a discharge supply pump (not shown) for returning the chemical solution from the doctor chamber 61A are installed in the doctor chamber 61A.

  On the other hand, as shown in FIG. 9, the chemical solution application part 53B in the form of the other doctor chamber has a doctor chamber 61B in which a chemical solution is placed facing the rotatable anilox roll 63B, and the doctor chamber 61B. The chemical solution is delivered to the anilox roll 63B. Further, a plate cylinder roll 64B that is in contact with the anilox roll 63B and is also in contact with the other surface of the laminated continuous sheet S2 is rotatably installed, and the chemical solution is delivered from the anilox roll 63B to the plate cylinder roll 64B. Yes. Further, a chemical solution is applied from the plate cylinder roll 64B to the laminated continuous sheet S2 while applying pressure to the laminated continuous sheet S2 with the impression cylinder roll 65B facing the plate cylinder roll 64B across the laminated continuous sheet S2. It is like that.

  Depending on the viscosity of the chemical solution, there is a problem that paper dust tends to adhere to the plate surface of the plate cylinder roll 64B. Therefore, it is preferable to provide the paper dust removing means 27 below the plate cylinder roll 64B. In the illustrated example of FIGS. 1 and 4, a rotating brush is used as the paper dust removing means 27. An air ejecting means 28 for ejecting air toward the rotating brush and separating the paper powder from the brush bristles can be provided for the paper dust removing means 27 composed of the rotating brush.

  In the present embodiment, the chemical solution application portion 53B is positioned on the other surface side of the laminated continuous sheet S2 that is not opposed to the roller 54A and is also not opposed to the winding drum 56A. A supply pump (not shown) for applying a chemical solution to the doctor chamber 61B and a discharge supply pump (not shown) for returning the chemical solution from the doctor chamber 61B are also installed in the doctor chamber 61B. .

  Accordingly, the chemical solution is applied to both surfaces of the laminated continuous sheet S2 from the chemical solution application unit 53A and the chemical solution application unit 53B. At this time, the coating amount on the surface side of the laminated continuous sheet S2 facing the roller 54A by the chemical solution application unit 53A Can be applied to the laminated continuous sheet S2 from both sides of the laminated continuous sheet S2, while reducing the amount of the liquid applied to the other surface side by the chemical applying unit 53B.

  Specifically, it is possible not only to change the coating amount on each side, but also to roughen the flexographic plate so that the number of lines of the flexographic plate is about 15 to 40 lines and the apex area ratio is about 20 to 40% so that the chemical solution does not scatter. By doing so, a dot pattern remains immediately after application, and an application part and an unapplication part can be instantaneously formed.

  Therefore, according to the present embodiment, the flexographic printing method allows the plate to be made of resin and is elastic, so that even if there are some irregularities on the sanitary thin paper, it can be adjusted by the printing pressure. Wrinkles are difficult to enter. On the other hand, by using the flexographic printing method, the coating amount can be stabilized even when the processing speed is high, and a wide range of chemical viscosity can be stably applied with one roll. Specifically, the application is also performed when the lotion agent to be used as a chemical solution is applied at a coating amount within the range described below while the laminated continuous sheet S2 is set to 700 m / min or more, preferably at a speed of 900 m / min or more. Is uniform and the laminated continuous sheet S2 can be wound without meandering.

(Chemical solution application process-an example of gravure application)
FIG. 10 shows an example of an apparatus related to gravure coating. In FIG. 10, the dip roll 31 picks up a certain amount of chemical solution from the chemical solution storage tray 308, and the chemical solution remaining in the cell of the dip roll 31 is transferred to the gravure roll 32. Next, the chemical liquid transferred to the gravure roll 32 is simultaneously transferred to the surface of the laminated sheet S <b> 2 while being scraped off by the scraping blade 33.

(Example of chemical)
Although it does not limit as a chemical | medical solution apply | coated to the tissue paper sheet which concerns on this invention, It shows about the example of the chemical | medical solution used suitably.
From the viewpoint of improving the processing speed, the viscosity of the chemical solution applied to the tissue paper is preferably 1 to 700 mPa · s at 40 ° C., and particularly preferably 50 to 400 mPa · s. If it is less than 1 mPa · s, the chemical solution is likely to be scattered, resulting in contamination of the apparatus. Conversely, if it is more than 700 mPa · s, it is difficult to control the coating amount.

  The component preferably contains 70 to 90% polyol, 1 to 15% moisture, and 0.01 to 22% functional chemicals.

  Polyols include polyhydric alcohols such as glycerin, diglycerin, propylene glycol, 1,3-butylene glycol, polyethylene glycol, and derivatives thereof, and sugars such as sorbitol, glucose, xylitol, maltose, maltitol, mannitol, and trehalose.

  Functional agents include softeners, surfactants, inorganic and organic fine particle powders, oily components, and the like. Softeners and surfactants have the effect of imparting flexibility to the tissue and smoothing the surface, and anionic surfactants, cationic surfactants and zwitterionic surfactants are applied. Inorganic and organic fine particle powders have a smooth surface. The oil component has a function of improving lubricity, and higher alcohols such as liquid paraffin, cetanol, stearyl alcohol, and oleyl alcohol can be used.

  In addition, as a functional agent, one of a hydrophilic polymer gelling agent, collagen, hydrolyzed collagen, hydrolyzed keratin, hydrolyzed silk, hyaluronic acid or a salt thereof, ceramide, etc. A moisturizing agent such as any combination can be added.

  Deodorants such as flavors, emollients such as various natural extracts, vitamins, emulsifiers that stabilize compounding ingredients, antifoaming agents, antifungal agents, organic acids, etc. An agent can be appropriately blended. Furthermore, you may contain the antioxidant of vitamin C and vitamin E.

Of the above components, it is preferable to use a polyhydric alcohol such as glycerin or propylene glycol as a main component in order to stabilize the viscosity and coating amount of the chemical solution.
The temperature at the time of chemical solution application is preferably 30 ° C to 60 ° C, preferably 35 ° C to 55 ° C.

(Configuration of chemical paper dust removing device main unit)
The secondary material roll of the example of the present invention is assumed to be folded not by a rotary interfolder but by a multi-stand interfolder with high productivity.
In the case of a rotary type interfolder, the processing speed (traveling speed of the sheet) is low. Therefore, as described in JP-A-2008-245780, in a rotary cylinder type processing machine, a wide sheet (for example, 2 to 3 m) is used. It is possible to apply a chemical in the process of supplying the degree).
However, it is conceivable that the tissue paper production line using the multi-stand type interfolder is set to a high speed of, for example, 700 to 1400 m / min. In that case, it is necessary to perform the ply processing at the same speed in the ply machine in order to match the production speed. In such a high-speed ply machine, for example, when a chemical solution is applied by a method such as gravure or flexo, a large amount of paper powder is generated mainly due to friction between a sheet running at high speed and a coating roll, It mixes and the density | concentration changes and causes the dispersion | variation in application amount. Therefore, in the present invention, equipment configured to apply a chemical solution on the plate cylinder while being applied to the tissue paper sheet running between the impression cylinder and the plate cylinder by a flexographic printing method or a gravure printing method, for example, a ply machine 1 and FIG. 4, a brush 27 that rotates while facing and contacting the plate surface of the plate cylinder (roll) 64B is provided, and a chemical solution containing paper dust is provided by the brush bristles. It is configured to be removed from the plate surface of the plate cylinder (roll) 64B. At this time, the difference between the peripheral speed of the plate surface of the plate cylinder (roll) 64B and the peripheral speed of the rotating brush is preferably about ± 5 to 10% with respect to the peripheral speed of the plate surface. By providing the peripheral speed difference, paper dust can be efficiently removed. However, if the peripheral speed difference is too large, the wear of the brush and the plate increases.

The chemical solution containing the paper dust removed from the plate cylinder (roll) 64B is collected in the service tank 23 and reused, and the paper dust content is discharged out of the system by the paper dust removing device main body 1.
The other examples will be described as follows.
FIG. 1 is a flow diagram showing an example of a chemical paper dust removing apparatus and a processing system according to the present invention. An endless metal mesh belt 11 is wound around the rolls 12 and 13. Further, an endless filter belt 10 is wound around the endless mesh belt 11 so as to surround the top and bottom and the outer periphery tension roll 14. The drive rotary roll 12 is connected to a belt drive speed reducer 21 to enable belt travel and travel speed control. Due to the rotation of the driving rotary roll 12, the mesh belt 11 and the filter belt are sandwiched and moved between the driving rotary roll 12 and the block roll 17.

  The filter belt 10 can be made of a resin such as polyester, a metal mesh sheet, or the like that is usually used in a belt type concentrator, but is moved while partially deforming the belt shape by pushing down, as will be described later. It is more preferable to use a resin filter having excellent flexibility. The chemical filtration is particularly intended to remove paper powder mixed in the chemical liquid, and the size of the paper powder is 0.3 to 3.0 mm in average fiber length. It is preferable to use ˜50 yarns having a thread thickness of 0.25 to 0.8 mm.

  The mesh belt 11 can be omitted, and the filter belt 10 can be wound directly around the drive rotating roll 12, but the mesh belt 11 is used to stabilize the shape of the filter belt and move the filter belt reliably. It is preferable to do. Since the mesh belt 11 does not add a filtering function, it is desirable to use a mesh that is sparse compared to the filter belt. The material of the mesh belt is preferably made of stainless steel, aluminum, polyethylene, or the like that hardly causes rust due to moisture adhesion. The metal chain mesh belt is preferably flexible enough to form a recess when the upper running surface is depressed.

  As shown in FIGS. 2 and 3, at least two places (four places in the illustrated example) of the upper running surface where the mesh belt 11 and the filter belt overlap are pushed down by the filter push-down roll 15, thereby forming a recess. The push-down means is not limited to a roll, and may be, for example, a resin convex part without corners. In that case, if the pushed-down filter belt is moved as it is, the belt is damaged due to friction between the push-down means and the belt. There is a fear.

  The concave portion formed by the push-down means becomes a chemical solution storage portion 16 into which the chemical solution to be filtered is directly introduced from the chemical solution supply pipe. The chemical solution storage unit is provided with a liquid amount detection means (not shown), and the filter belt moves when the storage amount exceeds a certain amount due to clogging of the filter. Any known liquid amount detecting means may be used as the liquid amount detecting means, and any known liquid amount detecting device such as a ball tap, a water level meter, a fine pressure sensor, or the like may be used.

  The filter push-down roll 15 is provided with two or more places, and more preferably four or more places. The arrangement of the filter push-down rolls is illustrated in FIG. 3, but the arrangement of the filter push-down rolls is particularly limited to the illustrated example as long as two or more filter push-down rolls are used and a recess is formed on the upper surface of the filter belt. It is not a thing. In order to form a concave portion with a large storage amount on the upper traveling surface, the distance a from the filter width direction side portion of the filter push-down roll located closest to the filter side portion is 10 to 10 times the length b in the width direction of the filter. 50%, more preferably 20 to 35% is preferable. If it is placed closer to the side than 10%, the recess cannot be made deep, and if it is closer to the center in the width direction than 50%, the side of the filter belt will bend more greatly, and the shape and capacity of the recess. Is difficult to stabilize.

  When the filter is clogged and the amount of liquid in the chemical solution storage part exceeds a certain amount, the clogged part moves forward, and the part that is not clogged forms a new chemical solution storage part. At this time, in the portion where the filter that has formed the recess becomes flat, there is a risk of liquid leakage from the side due to the chemical liquid that has moved along with the filter. Further, when the chemical solution moves forward and downward, the amount of the chemical solution to be subjected to centrifugation by the batch operation described later increases, the number of batch operations increases, and the operation becomes complicated. Therefore, a configuration is adopted in which a block roll 17 having a cross section on the side surface is provided so as to cross the part of the filter belt, and the chemical liquid that moves along with the movement of the filter is pushed back to the newly formed chemical liquid reservoir. desirable. The block roll 17 is made of a sponge foam, urethane foam or the like having a water absorbing surface, and is preferably disposed above the drive rotating roll 12. The chemical solution absorbed by the block roll 17 is pushed out to the chemical solution storage unit so as to be squeezed out by the pressure generated between the block roll 17 and the drive rotating roll 12.

  It is desirable that the filter belt after passing through the block roll 17 is configured such that clogging is removed by air injection from the air injection means 18 in front of or under the apparatus. The air ejecting means 18 is disposed in the internal gap formed by the filter belt, and blows away paper dust that causes clogging and a chemical solution remaining on the filter surface from the inside of the filter toward the outside. Is preferred. Specifically, an air compressor or the like can be used as the air injection means 18. The paper powder and the chemical liquid blown off by the air jet are stored in the chemical liquid receiver 19 and then sent to the centrifugal separator 22.

  The chemical solution that has passed through the filter belt of the chemical solution storage unit is stored in the filtrate receiving pan 20 and then sent to the service tank 23 or the service tank 24 (see FIG. 7).

(Centrifuge means)
The paper powder and the chemical liquid stored in the chemical liquid receiver 19 are further subjected to solid-liquid separation in the centrifugal separator 22. Centrifugation is preferably performed under the following conditions.
○ Bag filter: Made of resin, preferably made of polyester ○ Mesh size: 100-400 mesh ○ Amount of separated sample per time: 1.0-5.0 kg
○ Rotation speed: 2000-500rpm
○ Separation time: 15 to 45 minutes The separated chemical solution obtained by centrifugation is sent to the service tank 23 or the service tank 24 (FIG. 7).

(Form of chemical flow)
The uncoated chemical solution containing paper dust collected from the chemical solution coating process is sent to the centrifugal separator 22 or returned by the pump P-2, and after large contaminants such as paper pieces are removed by a screen or the like, the service is performed. It is stored in the tank 23. The temperature of the service tank 23 is preferably set to 20 to 60 ° C. by the heater 26 in order to keep the viscosity of the chemical solution within a certain range. The uncoated chemical solution in the service tank 23 is preferably added with the undiluted chemical solution sent from the undiluted solution tank 25 by the pump P-1. This is because, in order to uniformize the quality of the chemical solution added to the tissue paper, it is preferable to process and use the chemical solution integrally instead of separately introducing the circulating chemical solution and the stock solution into the line. The circulating drug solution and the stock solution are preferably mixed at a ratio of 4: 1 to 100: 1.

  The chemical liquid in the service tank 23 is supplied to the chemical liquid storage section 16 of the paper dust removing device main body 1 by the pump P-3, and is filtered by the filter belt 10. The filtrate stored in the filtrate receiving pan 20 is sent to the service tank 23 by the pump P-4.

  It is preferable that the chemical liquid and paper dust stored in the chemical liquid receiver 19 are supplied to the centrifugal separator 22 and further subjected to separation processing. The separated chemical liquid is sent to the service tank 23 by the pump P-5. The remaining separated pulp is treated as waste.

  The chemical solution in the service tank 23 is sent to the chemical solution application step by the pump P-6. At that time, an excessive amount of the chemical solution is sent, and the surplus is returned again to the service tank by the return pump P-7 from the coating apparatus (in the illustrated example, the doctor chamber 61).

  As the pumps P-1 to P-7, any known pump such as an air pump can be used. However, if the chemical liquid generates bubbles, the efficiency in the filtration process is reduced, and therefore it is preferable to use a gear pump that does not easily generate bubbles.

(Another form of chemical flow)
In FIG. 7, another example of piping of the paper dust removing apparatus main body 1 and the chemical solution application process is shown. As shown in FIG. 7, the chemical liquid stored in the filtrate receiving pan 20 and the chemical liquid receiver 19 may be sent to a service tank 24 different from the service tank 23. In this case, the uncoated chemical solution mixed with paper dust in the chemical solution coating process, the filtrate containing almost no paper dust, and the separation liquid are not mixed, and therefore, the chemical solution with less paper powder mixing is provided for the chemical solution coating step. Is preferable. However, since the filtration rate of the chemical solution is a rate limiting factor for supplying the chemical solution, it is preferable to use a large apparatus or a plurality of apparatuses having a high processing capability in order to stably supply the chemical solution.

  In this embodiment, the drug substance is preferably not mixed with the service tank 23 but mixed with the chemical supplied from the service tank 24 to the chemical liquid application process.

  When the viscosity of the uncoated chemical solution is 700 mPa · s or less (more preferably 400 mPa · s or less), the form of FIG. 1 can be used, but when the viscosity exceeds 700 mPa · s, the viscosity is less than 200 mPa · s. It is preferable to change to the form of FIG.

(About brush 27)
As shown in FIG. 5, the brush 27 includes a brush body in which brush hairs are planted in an appropriate dispersion state as shown in FIG. 5, and a plurality of brushes on the brush body shaft 27 a as shown in a partial view in FIG. 6. For example, a unit in which the hair units 27b are spirally arranged at appropriate intervals in the circumferential direction in units of 5 rows in the length direction as shown in the figure can be used more suitably. A space portion that is not planted is provided between the spiral strips.

In the example of FIG. 6, the reason why paper powder is not substantially accumulated is considered to be a space portion between the spiral stripes.
Further developmentally, when the rotation direction of the brush in FIG. 6 is clockwise on the right side, the paper dust can be sequentially collected on the left side. When the plate cylinder roll 64B is long, the spiral strips shown in FIG. 6 are symmetrically planted with the center as a boundary, and the paper dust can be sequentially collected from the center side to the left side and the right side.

  The brush 27 is preferably rotated so as to follow the rotation direction of the plate cylinder roll 64B, as shown in FIG. The rotational peripheral speed of the brush 27 is desirably about 80% to 40% slower than the rotational peripheral speed of the plate cylinder roll 64B.

  Furthermore, as shown in FIG. 4, an air injection means 28, for example, a nozzle, for injecting air toward the brush 27 and separating paper dust from the brush hair can be provided. 28A is a pneumatic pump.

  DESCRIPTION OF SYMBOLS 1 ... Paper dust removal apparatus main body, 10 ... Filter belt, 11 ... Metal chain mesh belt, 12 ... Drive rotation roll, 13 ... Inner circumference tension roll, 14 ... Outer circumference tension roll, 15 ... Filter push-down roll, 16 ... Chemical solution storage part , 17 ... Block roll, 18 ... Air injection means, 19 ... Chemical solution receiver, 20 ... Filtrate pan, 21 ... Decelerator, 22 ... Centrifugal means, 23, 24 ... Service tank, 25 ... Stock solution tank, 26 ... Heater, 27: Paper dust removing means, 28: Air jetting means, P-1 to P-7: Pump.

Claims (6)

The tissue paper sheet running between the impression cylinder and the plate cylinder is a facility configured to apply a chemical solution on the plate surface of the plate cylinder by a flexographic printing method or a gravure printing method,
A brush is provided so as to face and contact the plate surface of the plate cylinder, and the chemical solution containing paper dust attached to the plate surface of the plate cylinder is removed from the plate surface of the plate cylinder by the brush bristles. Paper dust removing device for tissue paper coating chemicals.   2. The paper dust removing device for a tissue paper coating chemical solution according to claim 1, wherein the sheet is configured to run vertically between the impression cylinder and the plate cylinder, and the brush is provided below the plate cylinder.   The paper dust removing device for a tissue paper coating chemical solution according to claim 2, wherein the brush is provided below the plate cylinder, and a chemical liquid collection receptacle is provided below the brush.   4. The paper dust removing device for tissue paper coating chemical solution according to claim 3, further comprising air jetting means for jetting air toward the brush to separate the paper dust from the brush bristles.   4. The tissue paper coating chemical solution according to claim 3, further comprising a paper powder separating means for separating paper powder from the chemical liquid collected in the chemical liquid receiving container, and a chemical liquid returning means for reusing the chemical liquid from which the paper powder has been separated. Paper dust removal device.   Using the paper dust removing device for tissue paper coating chemical solution according to any one of the preceding claims, the paper powder in the chemical fluid adhering to the brush bristles of a brush is removed. Paper dust removal method.

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