JP2004218186A - Method for spraying and imparting stain-proofing agent on canvas of paper machine, sliding/spraying device therefor and stain-proofing agent therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for surely spraying and imparting a suitable amount of a stain-proofing agent on a canvas of a paper machine, to provide a spray nozzle and a sliding/spraying device each for the method, and to provide a stain-proofing agent. <P>SOLUTION: The method for imparting the stain-proofing agent comprises applying a stain-proofing agent T on a canvas A for drying a paper substance in the paper machine. The stain-proofing agent T is sprayed on a contact-starting point C of the outer surface of the canvas A with an out roll B, attaching the stain-proofing agent T on the out roll B, transferring the stain-proofing agent T to the canvas A to impart through the out roll B. The stain-proofing agent is uniformly and surely imparted without imparting extraneous water not only into canvases having high air permeability but also into canvases having low air permeability and so hardly dried. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

  The present invention relates to a method for spraying a pollution control agent onto a canvas of a paper machine, and a spray nozzle and a pollution control agent used for the method.

In a paper product manufacturing (papermaking) process, drying of a paper body (wet paper) is essential, and good / bad drying has a great effect on the quality of paper products.
Therefore, the dry part (drying step) of the paper machine is positioned as a very important part in the paper making process.

In the dry part of a paper machine, drying of a paper body is usually performed by winding the paper body around the surfaces of a plurality of heated dryer rolls.
When a plurality of dryer rolls are used, a canvas is usually provided to press the paper body against the surface of the dryer roll from the outside to increase the drying efficiency.

FIG. 1 is a schematic diagram showing an example of a use form of a canvas in a dry part of a paper machine (for convenience, an upper canvas is partially omitted).
The canvas A is provided one above and below one for a group of about ten dryer rolls R (in the case of a double canvas), and is supported by a canvas roll K, a tension roll L, a canvas dryer M, etc. to form a closed loop. .

Then, the paper body W is sandwiched between the canvas A and the dryer roll R, and is strongly pressed against the surface of the heated dryer roll R to increase the drying efficiency of the paper body W.
The water vapor evaporated from the paper body W is normally discharged into a dryer pocket portion D which is a space surrounded by a dryer roll R and upper and lower canvases A and the like, and the ventilation of the same portion eventually causes the hood to cover the dry part. It is exhausted from the exhaust port.

The ventilation of the dryer pocket D is very important because it greatly affects the drying of the paper body.
Ventilation is performed by blowing hot air through a canvas with a hot-air roll, a hot-air duct, or the like, but is easily affected by the air permeability of the canvas.
Therefore, a canvas having an appropriate air permeability is selected and used.

Also in a single canvas system (including a single deck such as Bell Run) in which a single canvas holds a plurality of dryer rolls to dry a paper body, the air permeability of the canvas is important.
If the air permeability is not appropriate, phenomena such as ballooning and blowing may occur, which may lead to problems such as wrinkling of the paper body or breakage of the paper.

However, since the canvas makes strong contact with the paper body, conversely, the paper powder, pitch and the like contained in the paper body gradually transfer to the surface of the canvas that comes into contact with the paper body (hereinafter referred to as the outer surface of the canvas). In addition, the canvas is easily contaminated (see Patent Document 1).
Then, paper dust, pitch, and the like enter into the void portion (so-called canvas) of the canvas weave and clog the eyes, lowering the air permeability of the canvas, and as a result, significantly reducing the drying efficiency of the paper body.

Further, the paper powder, pitch, or the like transferred to the outer surface of the canvas may further transfer from the outer surface of the canvas to rolls in contact with the outer surface of the canvas.
Here, the rolls in contact with the outer surface of the canvas are, for example, the tension roll L and the canvas dryer M in FIG. 1, and include the outer canvas roll N on the outer surface side of the canvas among the canvas rolls K. (In the present specification, the rolls in contact with the outer surface of these canvases are collectively referred to as out-rolls).

When fine paper powder, pitch, and the like are successively transferred to the out roll via a canvas, the paper powder, pitch, and the like are tied to each other on the surface of the out roll, and gradually become a large mass.
Then, when the paper dust and the pitch accumulate and are formed in a layer on the surface of the out roll, the paper machine must be stopped and removed, and the production efficiency decreases (see Patent Document 1).

In addition, the mass having a certain size may be peeled off from the surface of the out roll and conversely transferred to the outer surface of the canvas.
This not only contaminates the canvas, but also in turn, the clumps transfer from the outer surface of the canvas to the paper body, causing defects in the paper product and causing paper breaks.

In this way, if the canvas is left to contaminate the canvas due to the gradual transfer of paper powder and pitch from the paper body W, various serious problems as described above will occur.
In order to prevent such a situation, an antifouling agent for preventing transfer of paper powder, pitch, and the like from the paper body to the canvas is usually applied to the canvas.

Heretofore, a method has been adopted in which an emulsion or the like of a stain inhibitor is sprayed directly on a canvas to apply the emulsion.
There has also been proposed a method in which an oil emulsion, which is an antifouling agent, is dropped onto a rotating shaft from a liquid reservoir above the canvas, and is scattered and applied as fine droplets by the centrifugal force of the rotating shaft (see Patent Document 2).

However, in these methods, the droplets of the anti-pollution agent are easily blown off by the surface airflow (associated airflow) accompanying the movement of the canvas, and the droplets do not reach the canvas surface, and the yield deteriorates.
Further, the blown-off droplets adhere to a member of a paper machine or the like and become large on the surface thereof, become droplets, and drop on a paper body (so-called dropping), which may significantly impair the quality of a paper product. .
Further, since the surface airflow of the canvas has become extremely intense due to the recent increase in speed of paper machines, most of the droplets are wound up by these methods, and a situation occurs in which the droplet cannot be effectively applied to the canvas surface.

As another application method, a method of applying a pollution control agent to a canvas via an out roll or the like immersed in an emulsion or the like of the pollution control agent has been adopted in some cases (see Patent Document 3).
However, in such a method, in many cases, a large amount of the antifouling agent is applied, so that the antifouling agent clogs the canvas, or the canvas gets wet, and the antifouling agent is not applied to the canvas accurately. Clogging was caused by powder and the like, and as a result, the drying efficiency of the paper body was significantly reduced.

In order to overcome these various problems, the present inventors present an invention of a method in which a pollution control agent is once applied to an outroll of a canvas, and an appropriate amount of the pollution control agent is applied to the canvas via the outroll. (See Patent Document 1 and Patent Document 4).
Here, a method of spraying from a fixed type spray nozzle, a method using a sliding type spray nozzle, and a method using a long type spray nozzle with respect to an out roll (particularly a tension roll) are presented (in particular, refer to Patent Document 1). ).

However, in the spraying method using the fixed spray nozzle, when the length of the outroll is long, a large amount of the pollution control agent is easily sprayed near the end of the outroll, and it is not always necessary to uniformly spray the entire surface of the outroll. It may not be easy.
In this respect, the long spray nozzle and the sliding spray nozzle can be uniformly sprayed on the entire surface of the out roll by arbitrarily determining the number of nozzles and the sliding width.

However, in the spraying method using a long spray nozzle, since the medicine is usually diluted several hundred times with water and used, the spray amount of the pollution control agent tends to be larger than in the case of the sliding spray nozzle. There is.
Further, the medicine may be sprayed to a portion where the canvas at both ends of the outroll is not in contact, and the medicine may accumulate in that portion to cause trouble.

On the other hand, the spraying method using the sliding spray nozzle does not cause such a problem, and has an advantage that the antifouling agent can be uniformly sprayed.
In addition, the type of nozzle to be used (for example, one-fluid nozzle or two-fluid nozzle), the amount of spray, the sliding speed of the nozzle, and the like can be freely adjusted, which is suitable for spraying an appropriate amount of a chemical solution.

In this case, if a one-fluid nozzle is used as the spray nozzle, the spray amount becomes too large, and the various problems described above occur. Therefore, a two-fluid nozzle is usually employed.
However, when a two-fluid nozzle is used, the momentum of the sprayed chemical solution is small, so that a part of the solution is wound up by the surface airflow of the outroll or the canvas, and the chemical solution may not reach the outroll.

  Therefore, the present inventors formed an air curtain on the upstream and downstream sides of the nozzle for ejecting the chemical solution as a device for preventing such a curling of the chemical solution, and cut off the surface airflow, and in the space therebetween. A fluid scattering prevention device for spraying a fluid for spraying a chemical has been proposed (see Patent Document 5).

However, in such an apparatus, especially when the paper machine is operating at a high speed, the air curtain may not always shut off the surface airflow, and conversely, the surface airflow may be greatly disturbed.
In such a case, the swirling of the chemical solution by the turbulent air current becomes rather intense, and a predetermined amount cannot be applied, and conversely, there is a possibility that the above-mentioned problem such as dropping may occur.

JP-A-2000-96476 (FIGS. 8-10 and 13) JP-A-7-292382 (page 4, FIG. 3) British Patent No. 2,284,833 (1995, FIG. 1) JP-A-11-217786 (FIGS. 3 and 4) Japanese Utility Model Publication No. 1-152762

As described above, the canvas is a member that plays an important role in drying the paper body, which greatly affects the quality of the paper product.However, since the canvas is in direct contact with the paper body, the paper powder and pitch are easily transferred, and the canvas is difficult to transfer. Contamination results in a significant decrease in paper body drying efficiency.
In order to prevent such contamination, a canvas is provided with a pollution control agent. However, if the medicine cannot be provided accurately, the canvas may be clogged or the canvas may be wetted, resulting in reduced drying efficiency.

  On the other hand, as the papermaking speed increases, the edges of the paper body running inside the paper machine are prevented from flapping and waving. And other canvases have come to be used.

Also, a needle-span-made canvas having naps provided on the surface of the canvas is used so that traces (irregularities) of the canvas texture do not remain on the surface of the paper product.
These canvases are more likely to be clogged with paper dust and the like and a pollution inhibitor and absorb moisture more easily than conventional canvases.
In particular, this tendency was remarkable in a canvas having an air permeability of 20000 cm ³ / cm ² / min or less.

From the viewpoint of the application of the antifouling agent to the canvas, the factors that make it difficult to apply year by year, such as increasing the speed of papermaking of the paper machine, strengthening the superficial airflow associated therewith, and improving the canvas as described above, etc. Increasingly, conditions are becoming more severe.
Conversely, even in such a severe environment, there is a strong demand for the development of a method for applying a more reliable and appropriate amount of a pollution control agent to a canvas.

The present invention has been made in order to overcome the above-mentioned problems against the background of the actual situation.
That is, an object of the present invention is to provide a method of spraying an antifouling agent which can reliably and appropriately apply an antifouling agent to a canvas.
Another object of the present invention is to provide a spray nozzle and a sliding spray device capable of realizing the spraying method.
It is still another object of the present invention to provide a stain inhibitor used in the spraying method.

  Thus, the present inventor has conducted intensive studies on such a background of the problem, and as a result, from the spray nozzle, the outer surface of the canvas that has circulated around the closed loop comes into contact with an out roll such as a tension roll or an outer canvas roll for the first time. It has been found that by spraying the anti-pollution agent toward the site (contact start site), an appropriate amount of the anti-pollution agent can be sprayed without being wound up in the surface airflow of the canvas. It has been completed.

  That is, the present invention relates to (1) a method of applying a stain inhibitor to a canvas used for drying a paper body in a paper machine, comprising the steps of: starting contact between an outer surface of the canvas and an out roll; The present invention is directed to a method of spraying a pollution control agent by spraying the pollution control agent from a spray nozzle toward a site, attaching the pollution control agent to an out roll, and transferring and applying the pollution control agent to a canvas via the out roll. .

  (2) The outroll is a method for spraying a pollution control agent, which is an outroll in which the canvas comes in contact with the paper body first.

  (3) A method of spraying a pollution control agent, which sprays the pollution control agent while sliding the spray nozzle in parallel with the rotation axis of the outroll of the canvas.

(4) The method for spraying a pollution control agent, wherein the canvas is a canvas having an air permeability of 20,000 cm ³ / cm ² / min or less.

  Further, the present invention resides in a sliding spraying device provided with a spraying nozzle used in the method of spraying a pollution control agent according to (5) or (3), wherein the spraying nozzle is a two-fluid nozzle.

  Also, a sliding spray device provided with a spray nozzle used in the method of spraying a pollution control agent according to (6) or (3), wherein the spray nozzle includes a two-fluid nozzle for spraying a liquid; An airflow injection nozzle for injecting an airflow, a secondary blow for injecting an airflow from the airflow injection nozzle to the liquid sprayed from the two-fluid nozzle and accelerating and spraying the sprayed liquid with the airflow The present invention resides in a sliding spray device which is a two-fluid nozzle.

  (7) The sliding spraying device is a sliding spraying device that slides a spraying nozzle based on a sliding width set by a limit switch.

  Further, the antifouling agent sprayed by the spraying method according to (8) or (1), wherein the antifouling agent is an antifouling agent which is an emulsion containing one or both of oil and wax. .

  Further, there is provided a stain inhibitor sprayed by the spraying method according to (9) or (1), wherein the stain inhibitor is a stain inhibitor which is an emulsion containing silicone oil.

  Further, the antifouling agent sprayed by the spraying method according to (10) or (1), wherein the antifouling agent is an antifouling agent which is an emulsion containing a modified silicone oil.

  The present invention can naturally adopt a configuration in which two or more selected from the above 1 to 10 are combined as long as the purpose is met.

ADVANTAGE OF THE INVENTION According to this invention, a suitable amount of a pollution control agent can be reliably provided to a canvas.
Not only a canvas having a high air permeability but also a canvas having a low air permeability (for example, 20,000 cm ³ / cm ² / min or less) and which is difficult to dry, is provided with an antifouling agent evenly and reliably without giving excess water to the canvas. In addition, it can be applied in an appropriate amount, which is more effective.
In addition, when the antifouling agent and the sliding spraying device of the present invention are used, the transfer of paper dust and pitch to the canvas is effectively prevented, and the antifouling effect is exhibited.

  Hereinafter, a method of spraying a pollution control agent onto a canvas of a paper machine according to the present invention, and a spray nozzle and a pollution control agent used for the method will be described with reference to preferred embodiments.

[About spraying method of antifouling agent]
FIG. 2 is a diagram illustrating a contact start site between the outer surface of the canvas and the outroll.
FIG. 3 is a schematic view of a state in which the anti-contamination agent is being sprayed from the spray nozzle toward the contact start site, as viewed from the side.

The spraying method of the antifouling agent of the present invention is characterized in that the antifouling agent T is sprayed toward the contact start site C between the outer surface of the canvas A and the out roll B while sliding the spray nozzle S. .
Here, the contact start site C is a site where the outer surface of the canvas A that has circulated around the closed loop first comes into contact with the outroll B, and is a hatched region in FIG.

In the figure, the canvas A moves at a high speed from above to below, and the outroll B rotates at a high speed corresponding to the movement of the canvas A.
Therefore, near the surface of the canvas A, a surface airflow is generated in the direction of the white arrow in FIG. 3, and also near the surface of the outroll B, a surface airflow is generated in the direction of the dotted arrow in FIG. 3.

In the spraying method of the antifouling agent of the present invention, the antifouling agent T is sprayed from the spray nozzle S toward the contact start site C as shown in FIG.
When sprayed in this manner, the pollution control agent T is carried and sprayed on both surface airflows of the canvas A and the outroll B.
On the other hand, since the surface airflow of the out roll B is generated, the state of dispersion of the anti-pollution agent T is concentrated by both surface airflows, and the anti-pollution agent T can accurately reach the contact start site C.
Naturally, the anti-contaminant T is applied efficiently without scattering over a wide area.

When spraying at the conventional spraying position Sa, the pollution preventive agent T is blocked by the hand going to the surface airflow (dotted arrow) of the out roll B, and a part thereof is wound up, so that the pollution preventive agent T is efficiently discharged. Not assigned to Roll B.
For example, if the amount of the contamination preventive agent T sprayed in the spraying by the long spray nozzle is increased in order to cover the decrease in the yield, the spraying amount of the dilution water increases, and the canvas becomes wet more than necessary.

According to the present invention, since the antifouling agent T is sprayed in the abutment region of the surface airflow of the outroll B and the surface airflow of the canvas A, the surface airflow is positively used.
In other words, the sprayed state is concentrated, and the contamination preventive agent T can reach the contact start site C without being wound up.

Here, the principle of the method for spraying a pollution control agent of the present invention will be described.
In the spraying method of the antifouling agent of the present invention, the antifouling agent is sprayed from the spraying nozzle toward a contact start site of the outer surface of the canvas and the outroll to adhere the antifouling agent to the outroll, The use of the transfer of the inhibitor from the outroll to the canvas allows the contamination inhibitor to be applied to the canvas.

As shown in FIG. 1, the canvas A is pressed into contact with a plurality of dryer rolls R heated to, for example, about 80 to 100 ° C. via a paper body W, and on the other hand, is directly heated and dried by a canvas dryer M.
Therefore, the canvas A is traveling in a high temperature state, and the tension roll L and the outer canvas roll N (that is, the out roll) in contact therewith are always transferred from the dryer roll R and the canvas dryer M via the canvas A, and the high temperature It is rotating in the state.

When the anti-pollution agent is sprayed and adhered to such high-temperature out-rolls, excess water in the anti-pollution agent evaporates, but the wax and oil in the anti-pollution agent are turned into oil by heat and become less viscous. , Diffuses to the surface of the out roll to form an oil film.
Then, a part of the oil film is transferred from the out roll to the entire outer surface of the canvas A as if the paint is applied to the wall by a roller, whereby uniform application of oil and the like to the outer surface of the canvas can be achieved ( Paint roller effect).

In addition, since an appropriate amount of oil is uniformly applied only to the outer surface of the canvas in a high temperature state, a thin oil film is effectively applied to the canvas surface without wetting the canvas or clogging the canvas. It is formed.
By forming the oil film on the canvas in this way, it is possible to sufficiently and effectively prevent the transfer of paper powder, pitch, and the like from the paper body.

  Furthermore, since oil and the like are transferred only to the surface layer of the canvas in this way, a canvas usually used for a paper machine, that is, a plain weave combining a monofilament or a multifilament, a double weave, a triple weave, a needle type, a spiral type, Compatible with any canvas such as surface span type.

That is, as described above, in a conventional canvas having a permeability of 20,000 cm ³ / cm ² / min or less, clogging of the canvas frequently occurs due to paper dust or oil of a pollution inhibitor, or excess moisture is generated. The tendency to absorb and easily wet was remarkable.
However, according to the present invention, oil and the like can be transferred only to the surface layer portion of the canvas by the paint roller effect as described above, so that the contamination inhibitor can be applied to such a canvas without any problem.

The spray application method of the antifouling agent of the present invention is a method of appropriately replenishing an appropriate amount of an oil film oil or the like (antifouling agent) which is lost little by little from the surface of the out roll due to the paint roller effect.
The application of such a contamination inhibitor can be performed by using a long spray nozzle having a plurality of nozzle openings.

However, as described above, when spraying the pollution control agent with a long spray nozzle, the drug is usually used by diluting it several hundred times with water, and when spraying simultaneously over the entire surface of the out roll, A large amount of water may transfer to the canvas, causing the canvas to get wet.
In this regard, in the sliding type spray nozzle which sprays while sliding one spray nozzle in parallel with the out roll, the anti-pollution agent is sprayed as it is without dilution with water, so that the canvas is reliably prevented from wetting. Can be preferred.

The amount of the anti-contaminant sprayed on the out rolls varies depending on various factors such as the speed of paper making, the material and width of the canvas, the number of out rolls, the type of paper product, the number of dryer rolls held by the canvas, and the temperature. .
However, in the present invention, by spraying with the above-described spray nozzle (a long spray nozzle or a sliding spray nozzle), the spray amount is changed by changing the spray amount or sliding speed, or by changing the spray nozzle. Fine adjustments can be made immediately and accurately.

Further, as shown in FIG. 3, when spraying toward the contact start site between the outer surface of the canvas and the outroll, a part of the pollution control agent (oil, water, etc.) may be applied to the canvas, Immediately after that, it comes into immediate contact with the outroll, and as a result, the same effect as when the entire amount is directly sprayed on the outroll is obtained.
Also, the moisture in some of the directly applied anti-pollution agents is such that it immediately dries out in contact with out rolls, canvas dryers, dryer rolls, etc., so that oil film formation on the canvas surface is affected. Not something.

Incidentally, the oil of the pollution control agent transferred from the out roll (for example, a tension roll) to the canvas is transported to the canvas, and a part of the oil is also transferred to the paper body or other out rolls (for example, the canvas dryer or the outer canvas roll). And adhere.
Oil adhering to other out rolls forms an oil film on the roll surface.

However, not only does the oil supply from the canvas continue to be unilaterally continued, but when the oil accumulates to a certain extent, on the contrary, the oil is transferred from another outroll to the canvas.
In this way, in the other out-rolls, the exchange of oil with the canvas reaches an equilibrium state, and the state where the oil film is kept at a constant thickness on its surface continues.

The oil transferred to the paper body is carried by the paper body and is finally removed from the paper machine together with the paper body.
Therefore, it is necessary to continuously supply the anti-pollution agent to the out rolls.

As described above, in a state in which an appropriate amount of the pollution control agent (oil or the like) is sprayed, if the pollution control agent is sprayed on one out roll, an oil film is formed not only on the out roll but also on the other out rolls. .
As a result, all out-rolls can be protected from contamination by paper dust or pitch derived from the paper body.

[About the spray position of the pollution control agent]
According to the method of spraying the antifouling agent of the present invention, unlike the conventional method, the antifouling agent is sprayed against the surface airflow of a canvas or an outroll (see Sa shown by a broken line in FIG. 3). Utilizing those surface airflows as described above.
In other words, the anti-pollution agent is carried on the surface airflow of the superficial layer so as to reach the contact start site accurately, so that the anti-pollution agent is reliably and appropriately applied to the canvas (via an out-roll). Solved the problem.

Furthermore, the idea of carrying this antifouling agent on the surface airflow of a canvas or an outroll has unexpectedly produced a new advantageous effect, and will be described here.
As described above, the conventional spraying method (see Sa in FIG. 3) is susceptible to obstruction by the surface airflow of the canvas and the out roll, and in fact, the out roll is in a state of being drawn deeply like the tension roll L. It could only be done with a roll (position S5 in FIG. 4).

  On the other hand, according to the spraying method of the present invention, as will be verified later in the examples, the outrolls which are susceptible to the surface airflow of the canvas or the like and are shallowly retracted to the extent that they are pressed against the canvas (FIG. 4) (See S1 for the canvas roll N, S3 for the canvas dryer M, etc.) can also exert their functions sufficiently.

That is, according to the present invention, the spraying of the antifouling agent to the out-roll which is difficult to be realized by the conventional method can be accurately performed without winding up the antifouling agent.
Therefore, the present invention has an advantage that it can be applied to any outroll.
In addition, as described above, the anti-pollution agent (oil) sprayed on the out-roll is transferred to another out-roll via a canvas and forms an oil film to prevent the out-roll from being contaminated. And prevent contamination of the canvas.

Therefore, when a plurality of out-rolls are provided, if an anti-pollution agent is applied to the out-roll located upstream in the moving direction of the canvas, the anti-pollution agent (oil) is transferred to the other out-rolls downstream. However, the contamination can be more effectively prevented.
That is, in the spraying method of the present invention, it is more preferable to spray the anti-contamination agent on the out-roll (outer canvas roll N in FIG. 4) where the canvas comes in contact with the paper body first.

[About sliding sprayer]
In the spraying method of the antifouling agent of the present invention, a long spray nozzle can be used. However, as described above, since the agent is used after being diluted several hundred times with water, it wets the canvas. There are cases.
In that respect, the sliding type spray nozzle has an advantage that the antifouling agent can be sprayed as it is without diluting it with water.

Therefore, first, a sliding spraying device for sliding the spraying nozzle will be described.
FIG. 5 is a schematic diagram showing a configuration example of the sliding spraying device.
This configuration example shows a case where the spray nozzle is a two-fluid nozzle.
The sliding spray device 1 includes a frame 11, left and right box portions 12L and 12R, a spray nozzle S, a moving belt 13 for fixing and sliding (reciprocating) the spray nozzle S, a drive motor 14, and left and right limit switches. 15L and 15R are provided.

The spray nozzle S is fixed to and supported by a support 16 standing upright from a support base 13a mounted and fixed to the moving belt 13.
A liquid supply pipe 17 for supplying a pollution control agent and an air supply pipe 18 for blowing are attached to the spray nozzle S, and their lower ends are fitted and fixed to the support base 13a.

The liquid supply pipe 17 and the air supply pipe 18 are connected to the corresponding tubes 17a and 18a inside the frame body 11, respectively.
The tubes 17a and 18a are inserted into a cable carrier 19 that changes the shape flexibly in accordance with the reciprocating movement of the moving belt 13, and follows the cable carrier 19, passes through the inside of the left box portion 12L, and a chemical solution tank, a compressor or the like (not shown). ).

The moving belt 13 is stretched between a roller in the right box portion 12R and a roller (both not shown) driven by the drive motor 14 in the left box portion 12L.
The frame body 11 is provided with left and right limit switches 15L and 15R, and the sliding width of the spray nozzle S can be set by these limit switches.

That is, in the sliding spray device 1, by driving the drive motor 14 to move the moving belt 13 in the forward or reverse direction, the spray nozzle S slides based on the sliding width set by the limit switch. It can be reciprocated (slid) in the longitudinal direction of the dynamic dispersion device 1.
Therefore, it is possible to prevent as much as possible the spraying of the medicine to a portion where the canvas at both ends of the out-roll does not contact, and the trouble does not occur due to the accumulation of the drug in that portion as in the above-described conventional example.

Further, the flexible tubes 17 a and 18 a connected to the liquid supply pipe 17 and the air supply pipe 18 can follow the deformation of the cable carrier 19.
Therefore, while the spray nozzle S slides, the anti-pollution agent and the blowing air can be continuously supplied, and the sprinkle nozzle S can continuously spray the anti-pollution agent while sliding.

[About spray nozzle]
Next, the spray nozzle will be described.
As the spray nozzle S, a one-fluid nozzle or a two-fluid nozzle is usually employed.
The one-fluid nozzle applies pressure to the liquid and ejects the liquid. The amount of the injected liquid is large, and the liquid has a large impact (flow velocity, momentum, etc.).
The two-fluid nozzle extrudes and sprays a liquid with blow air, and is suitable for spraying a small amount of a liquid, but has a feature of relatively small impact.

  As described above, in spraying the canvas with the antifouling agent, it is an essential condition that the drying efficiency of the paper body by the canvas is not reduced, so that the canvas is not wet and the canvas is not clogged. A significant amount of stain control agent must be provided.

Therefore, it is preferable to spray the undiluted water as little as possible, preferably without diluting with water, which dilutes the pollution control agent. Therefore, in the sliding spraying apparatus of the present invention, a two-fluid nozzle is used as the spraying nozzle. Is preferred.
At this time, various two-fluid nozzles have been developed and put on the market, but it goes without saying that the two-fluid nozzle is appropriately selected or designed based on the amount of the anti-contamination agent sprayed.

[About two-fluid nozzle with secondary blow]
As described above, the spray application method of the present invention is to apply the anti-contamination agent by putting it on the surface airflow of a canvas or an out-roll. Therefore, even when a two-fluid nozzle is used, it is possible to sufficiently prevent curling. A stain inhibitor can be provided.
However, when the papermaking speed of the paper machine is extremely high and the surface airflow of the canvas or the like (see the white arrow and the dotted arrow in FIG. 3) is strong, it is necessary to ensure that the antifouling agent reaches the canvas. In addition, a two-fluid nozzle with a secondary blow can be used as a spray nozzle.

  The two-fluid nozzle with the secondary blow includes a two-fluid nozzle for spraying a liquid (contamination inhibitor) and an airflow jet nozzle for jetting an airflow (secondary blow), and is sprayed from the two-fluid nozzle. An airflow is jetted from the airflow injection nozzle to the liquid, and the sprayed liquid is accelerated by the airflow and sprayed onto the canvas.

6: is a figure which shows the example of a structure of the two-fluid nozzle with a secondary blow, (A) is a perspective view, (B) is XX sectional drawing of (A) (however, in (B), The two-fluid nozzle is indicated by a dashed line).
Arrows in FIG. 6B indicate the flow of the secondary blow air.

In the present configuration example, the two-fluid nozzle 2 with the secondary blow includes the two-fluid nozzle 3 and the air box 4, and the two-fluid nozzle 3 is fitted and screwed into the substantially U-shaped air box 4 (illustrated). None).
The two-fluid nozzle 3 includes a spray nozzle 31, a liquid inlet 32, and an air inlet 33.

The two-fluid nozzle 3 (spray nozzle 31) is appropriately selected and used based on the amount of the contamination preventive agent sprayed, similarly to the two-fluid nozzle described above.
The liquid supply pipe 17 (see FIG. 5) is screwed into the liquid inlet 32, and the air supply pipe 18 is screwed into the air inlet 33 via a sealing.

A concave portion is formed inside the side wall 41 of the air box 4, and forms an airflow injection nozzle 42 surrounded by the side wall 41 and the side wall of the two-fluid nozzle 3.
In place of the support 16 in FIG. 5, a secondary blow air supply pipe 21 for supplying secondary blow air is provided via a sealing to the secondary blow air inlet 43 at the bottom of the air box 4. It is screwed.
Although not shown, the secondary blow air supply pipe 21 is fitted and fixed to the support base 13a like the liquid supply pipe 17 and the like, connected to the tube, inserted into the cable carrier, and connected to a compressor or the like outside the apparatus. Needless to say.

The two-fluid nozzle 2 with the secondary blow having the above configuration is used as the spraying nozzle S attached to the sliding spraying device 1 shown in FIG.
When compressed air (secondary blow air) is supplied from the secondary blow air supply pipe 21 to the two-fluid nozzle 2 with secondary blow having such a configuration, the compressed air passes through the secondary blow air inlet 43, The air is injected from the airflow injection nozzle 42 through the hole 45 to fill the space 44 and form the secondary blow E.

FIG. 7 is a diagram showing a state in which a pollution control agent is sprayed from a two-fluid nozzle with a secondary blow.
When the secondary blow E is jetted from the airflow jet nozzle 42 to the anti-pollution agent T sprayed from the spray nozzle 31 of the two-fluid nozzle 2 with the secondary blow, the anti-pollution agent T is converted into the secondary blow E having a higher flow velocity. It can be easily seen from FIG. 7 that it is accelerated.
In this way, the two-fluid nozzle with the secondary blow can make the ejection of the liquid by the two-fluid nozzle having originally low impact a strong impact.

[About pollution control agents]
Examples of the antifouling agent used in the method of spraying the antifouling agent of the present invention include an emulsion containing wax or oil or both.
Waxes and oils are preferably used as mold release agents because they are easily oiled and diffused on the surface of the outroll and can form an oil film having more effective water repellency.

Above all, vegetable oils such as castor oil and rapeseed oil are preferably used as a stain inhibitor because they have good fixability on a canvas or an out roll and do not impair the printability of paper.
Silicone oil is preferably used as a main component of a stain inhibitor because it forms a film having the releasability and water repellency unique to silicone oil on the surface of a canvas or an out roll.

Various silicone oils can be used.
Above all, dimethylpolysiloxane-based oils (commonly known as "dimethyl") are characterized by an extremely large number of types, and can be appropriately selected and used according to the conditions of use such as the material of the canvas and the temperature at the time of use. ,preferable.

In addition to the above-mentioned dimethylpolysiloxane-based oil, modified silicone oils in which side chains and terminal groups are variously substituted with other organic functional groups are commercially available as silicone oils, and are preferably used.
The modified silicone oil has various modified types depending on the substituent, such as amino-modified, epoxy-modified, alkoxy-modified, carboxy-modified, carbinol-modified, and mercapto-modified.

In addition, depending on the substitution position, it is divided into side chain type, both terminal type, one terminal type, side chain both terminal type, etc., and depending on the combination of this substitution position and the above modified type, etc., the modified silicone oil has unique characteristics. .
For example, side chain amino-modified silicone oil is more difficult to wipe than dimethyl (mostly wiped off once) in an experiment in which it is attached to an acrylic plate and wiped off with tissue paper (usually, it cannot be wiped off with a single wipe) (Oil film remains).

That is, the side chain type amino-modified silicone oil has the property of having a strong adhesiveness (fixing property) to plastics, and in fact, strongly adheres to synthetic fibers and metal plates.
This is thought to be because the organic functional group having the side chain polarity strongly attracts to the metal plate or the like and exerts an anchoring effect on the surface of the metal plate or the like.

If such a modified silicone oil is used in the method of spraying a pollution control agent of the present invention, the modified silicone oil once adhered to the canvas or out roll is strongly adhered to them and does not easily fall off them, so that it is preferable. .
In addition, because of such characteristics, the amount of oil transferred to the paper body and removed therefrom is reduced as described above, so that there is also an advantage that the applied amount of the antifouling agent can be reduced.

Therefore, problems such as clogging of the canvas can be more reliably prevented.
Also, due to the strong tackiness of the modified silicone oil, it immediately adheres to the canvas immediately after the application of the antifouling agent, and immediately forms an oil film on the out roll. There is also the advantage of being fast.

  As described above, the amount of the antifouling agent to be applied is determined by the material and width of the canvas, the number of dryer rolls and the temperature setting, the type of paper product to be manufactured, the paper speed, the material of the outroll to be applied, and the temperature during use. And the main components (wax, oil, silicone oil, modified silicone oil) of the stain inhibitor.

Hereinafter, examples will be described.
It goes without saying that the invention is not limited to these examples.

(Pollution inhibitor)
The stain inhibitor (emulsion) was prepared as follows.
(Modified) silicone oil or castor oil 10% by weight
Emulsifier [Emulgen 109P (manufactured by Kao Corporation, polyoxyethylene lauryl ether, nonionic type)] 2% by weight
88% by weight of water
100% by weight in total

(Papermaking conditions)
Paper machine: Ultra Former (Kobayashi, Ltd.)
Papermaking brand: Liner Basis weight: 160 g / m ²
Paper speed: 650 m / min Paper width: 4 m
Canvas width: 4.5m
In addition, the air permeability of the used canvas is 16000 cm ³ / cm ² / min.
As shown in FIG. 4, the out rolls were arranged in the order of the outer canvas roll N, the tension roll L, and the canvas dryer M from the upstream side of the canvas.

(Spray conditions)
Using the sliding spray device shown in FIG. 5 (spray nozzle is a two-fluid nozzle), the spray amount of the pollution control agent was set to 5 cm ³ / min, the sliding speed, the spray position (S1 to S6 in FIG. 4), and the silicone. Changed the type of oil and sprayed for 14 days.
Incidentally, in FIG. 4, S1, S2, and S3 show the case where the spraying is performed toward the contact start portion between the outer surface of the canvas and the outroll in the present invention, and S4 and S5 show the conventional spraying positions that are sprayed on the outroll, Indicates the case of spraying directly on the outer surface of the canvas.

By the way, the spray amount of the stain inhibitor of 5 cm ³ / min is equivalent to spraying 0.19 mg / m ^{2 of} oil when the specific gravity of the emulsion is 1.0 g / cm ³ .
The calculation formula is shown for reference.
(Calculation formula) 5 cm ³ / min ^{× 0.1 × 1.0g / cm 3 ÷} (650m / min × 4.0 m)
= 0.5 g / min ÷ 2600 m ² / min = 500 mg / min ÷ 2600 m ² / min = 0.19 mg / ^{m 2}

[Results and evaluation]
The results are shown in [Table 1].
In Table 1, the sliding speed indicates the sliding speed of the spray nozzle.
N, L, and M represent the outer canvas roll N, the tension roll L, and the canvas dryer M, respectively, in FIG.

At this time, the evaluation was performed visually and classified as follows.
：: Dirt (paper dust, pitch, etc.) cannot be confirmed on the canvas or outroll. ○: Dirt is very slightly adhered on the canvas or outroll. △: Dirt is adhered on the canvas or outroll. ×: Canvas. Is clogged, or dirt is formed in layers on the out roll.

[When the sliding speed of the spray nozzle is changed]
In the spraying method of the present invention, the sliding speed of the spray nozzle is preferably 1.5 m / min or more.
That is, as shown in Examples 1 to 3, Example 8, Example 4, and Example 9, the sliding speed of the spray nozzle is changed at the position S1 in FIG. 4 to change the dimethyl silicone oil (dimethyl polysiloxane oil). When it is compared with the case of spraying, it can be seen that dirt adheres to the canvas and the like as the sliding speed decreases.
When the sliding speed is lower than 2.0 m / min, it can be seen that small dirt is beginning to form on the canvas and the like.

It is considered that this is because if the sliding speed of the spray nozzle is too low, replenishment of the oil cannot keep up with the depletion of the oil film on the out roll.
In other words, the oil film peels off one after another on the part of the surface of the out roll that has not been sprayed with the anti-pollution agent, and the canvas cannot effectively receive the oil supply from that part of the out roll, and the surface of the canvas also An oil film cannot be formed effectively.
For this reason, the transfer of the paper dust and the pitch from the paper body is allowed, and the paper dust and the like are carried by the canvas and transferred to other out rolls to be contaminated.
From these facts, it can be understood that the sliding speed of the spray nozzle affects the prevention of stains on the canvas and the like.

[When using modified silicone oil]
This tendency is the same when the side chain type amino-modified silicone oil is used instead of dimethyl (Examples 4 and 9).
However, as can be seen by comparing Example 3 and Example 4 (and Example 8 and Example 9), the use of the modified silicone oil at a lower sliding speed than the use of dimethyl at the same sliding speed prevents contamination. The effect is good and improvement is seen.

[When spraying position is changed]
Spraying positions of the antifouling agent were S1 (Example 1), S2 (Example 5), S3 (Example 6), S4 (Comparative Example 1), S5 (Comparative Example 2), and S6 (Comparative Example 3). Comparing the changed cases, S1 to S3 sprayed by the spraying method of the present invention showed a good effect of preventing contamination.

In S4, winding of the droplets of the contamination inhibitor was observed.
It is considered that the reason why the effect of preventing the contamination in S4 is scarcely confirmed is that a sufficient amount of the contamination inhibitor did not reach the outer canvas roll N due to the violent winding of the canvas by the surface airflow.

Also in S5, it was observed that some of the droplets of the stain inhibitor were rolled up.
Compared to the case of S4, good results are obtained because the amount of winding is small.
However, when compared with Example 5 sprayed in S2, the effect of preventing contamination was not sufficient, and as a result of being wound up as described above, the amount reaching the tension roll L was reduced and did not reach the required amount. It is.

When the antifouling agent was directly applied to the canvas in S6, both the canvas and the outroll were heavily contaminated.
At this time, the stain inhibitor was wound up violently.
Although not shown in Table 1, the results were similar when an emulsion of a side chain type amino-modified silicone oil was used instead of dimethyl.

A similar experiment was performed using a two-fluid nozzle with a secondary blow in place of the two-fluid nozzle, but the roll-up was almost suppressed, but the result that the canvas and the out-roll were contaminated remained unchanged.
In other words, if it is directly sprayed on the canvas, even if the pollution inhibitor (oil, water, etc.) reaches the canvas, it is absorbed on the spot and does not diffuse in the plane direction.

Therefore, the oil in the canvas portion on which the antifouling agent is not sprayed is transferred to the paper body and lost, and conversely, the transfer of paper powder and pitch is allowed to be contaminated (that is, when the oil is sprayed on the out roll). Paint roller effect cannot be obtained).
Further, since an effective oil film is not formed on the out-roll, it is considered that paper powder and the like are successively transferred from the canvas and accumulated.

[More effective spray position]
Example 1, Example 5, and Example 6 are the cases where only the spraying position of the stain inhibitor by the spraying method of the present invention was changed.
The result shows that
(1) An oil film is formed on the out-roll on which the antifouling agent has been sprayed, and the oil is also transported to the downstream out-roll via a canvas, effectively forming an oil film.
(2) However, the out-roll on the upstream side of the out-roll on which the antifouling agent is sprayed may be slightly stained with paper dust, pitch, or the like.
That's what it means.

Considering these causes, (1) can be easily understood from the above-described principle of the method for spraying the antifouling agent of the present invention.
As for (2), when the canvas is pressed against the paper body, as described above, a part of the oil is transferred to the paper body, so that the out-roll located immediately after that (the above-described upstream out-roll) It is considered that the amount of the oil which is transferred to ()) is reduced, and the effect of preventing contamination is slightly reduced.

Further, when the canvas is pressed against the paper body, paper dust, pitch, and the like may be accidentally transferred.
Usually, such paper dust is transferred from the canvas to the paper body while the canvas orbits and does not return and the canvas is not contaminated, but some of the outrolls have a slightly reduced pollution prevention effect as described above. It is considered that the outroll is slightly contaminated because it is transferred and trapped.

Therefore, according to the spraying method of the present invention, it is possible to effectively prevent contamination on all outrolls by spraying the anti-contamination agent on the outroll where the canvas first comes into contact with the paper body. .
Further, as can be seen from a comparison between Example 3 and Example 4, the use of the modified silicone oil is more effective.

[When vegetable oil is used]
In the case of using castor oil as the main component of the antifouling agent (Example 7), as in the case of using dimethyl silicone oil (Example 1), dirt (paper powder, pitch, etc.) was confirmed on the canvas and out-roll. However, good results were obtained.
This is because, like dimethyl or side chain amino-modified silicone oil, castor oil also fixes to the surface of the canvas or out-roll and effectively forms an oil film, effectively preventing the transfer of paper dust and pitch. It is thought that it is.

[Air permeability of canvas]
Finally, the air permeability of the canvas is described.
In a conventional spraying method, as described above, in a canvas having an air permeability of 20,000 cm ³ / cm ² / min or less, clogging of the canvas frequently occurs due to paper dust, oil of a pollution inhibitor, etc. There was a tendency to absorb moisture and get wet easily.
According to the invention of the present application, such a problem is solved, and on the contrary, a more excellent effect can be exhibited in this range of the air permeability.
In order to verify this, a canvas having 25,000 cm ³ / cm ² different from the canvas of the paper making conditions (that is, 16000 cm ³ / cm ² / min) in the above-described example was used, and the other conditions were the same. A 14-day spray experiment was performed.
The spraying position was set at S2 (Example 10) and S5 (Comparative Example 4) on the tension roll L.
The results are shown in [Table 2].

From the results of Example 5, Example 10, Comparative Example 2, and Comparative Example 4, it can be understood that the spraying method of the present invention exerts more excellent effects as the air permeability is smaller.
Therefore, it is suitable for producing delicate thin paper.

Although the present invention has been described above, the present invention is not limited to only the embodiment, and it goes without saying that various other modifications can be made without departing from the essence of the present invention.
For example, in the present invention, a two-fluid nozzle is mainly described, but a one-fluid nozzle may be used in some cases.

Further, regarding the modified silicone oil, the side chain type amino-modified silicone oil is mainly described in this specification, but this is merely an example, and it is a matter of course that an oil with another substituent or an oil at another substitution position may be used. It is possible.
Furthermore, in a canvas (inner roll type) in which the canvas rolls including the tension rolls and the like are all provided on the inner side (inner side), the present invention is implemented by, for example, pressing the canvas rolls from the outside of the canvas. be able to.

The method for spraying the antifouling agent onto the canvas of the paper machine of the present invention, and the sliding spraying device and the antifouling agent used for the method are not limited to paper machines, but are applicable to the general technical field of the paper industry as long as the principle is applied. Available.

FIG. 1 is a schematic diagram showing an example of a use form of a canvas in a dry part of a paper machine. FIG. 2 is a diagram illustrating a contact start site between the outer surface of the canvas and the outroll. FIG. 3 is a schematic view of a state in which the anti-contamination agent is being sprayed from the spray nozzle toward the contact start site, as viewed from the side. FIG. 4 is a schematic view showing a position where the contamination inhibitor is sprayed in FIG. FIG. 5 is a schematic diagram showing a configuration example of the sliding spraying device. 6: is a figure which shows the example of a structure of the 2 fluid nozzle with a secondary blow, (A) is a perspective view, (B) is XX sectional drawing of (A). FIG. 7: is a figure which shows the state which sprays a pollution control agent from a 2 fluid nozzle with a secondary blow.

Explanation of reference numerals

DESCRIPTION OF SYMBOLS 1 ... Sliding spraying apparatus 11 ... Frame 12L ... Left box part 12R ... Right box part 13 ... Moving belt 13a ... Support base 14 ... Drive motor 15L ... Left limit switch 15R ... Right limit switch 16 ... Support 17 ... Liquid supply Pipe 18 Air supply pipes 17a, 18a Tube 19 Cable bear 2 Two-fluid nozzle 21 with secondary blow Air supply pipe 3 for secondary blow 3 Two-fluid nozzle 31 Spray nozzle 32 Liquid inlet 33 Air Inlet 4 Air box 41 Side wall 42 Air jet nozzle 43 Secondary air inlet 44 Space 45 Hole A Canvas B Out roll C Contact start site D Dryer pocket E Secondary Blow K ... Canvas roll L ... Tension roll M ... Canvas dryer N ... Outer canvas roll R ... Dryer roll S ... Spray nozzle Sa ... Conventional Spraying position S1, S2, S3, S4, S5, S6 ... spraying position T ... antifouling agent W ... paper body

Claims (10)

A method of applying a stain inhibitor to a canvas used for drying a paper body in a paper machine, comprising the step of spraying a stain inhibitor from a spray nozzle toward a site where contact between an outer surface of the canvas and an out roll starts. A spraying method, wherein the anti-staining agent is attached to an out roll, and the anti-staining agent is transferred to the canvas via the out roll and applied.   2. The method according to claim 1, wherein the outroll is an outroll where the canvas comes in contact with the paper body first.   2. The method for spraying a pollution control agent according to claim 1, wherein the spraying nozzle sprays the pollution control agent while sliding the spray nozzle in parallel with the rotation axis of the outroll of the canvas. The canvas, spray applying process according to claim 1, wherein the antifouling agent, wherein the air permeability is 20000cm ³ / cm ² / min or less canvas.   A sliding spraying device provided with a spraying nozzle used in the method of spraying a pollution control agent according to claim 3, wherein the spraying nozzle is a two-fluid nozzle.   4. A sliding spray device comprising a spray nozzle used in the method of spraying a pollution control agent according to claim 3, wherein the spray nozzle is a two-fluid nozzle for spraying a liquid and an air flow for injecting an air stream. A two-fluid nozzle with a secondary blow, comprising: a jet nozzle; and jetting an airflow from the airflow jet nozzle to the liquid sprayed from the two-fluid nozzle, and accelerating and spraying the sprayed liquid by the airflow. A sliding spraying device characterized by the above-mentioned.   7. The sliding spraying device according to claim 5, wherein the sliding spraying device slides the spraying nozzle based on a sliding width set by a limit switch.   The antifouling agent sprayed by the spraying method according to claim 1, wherein the antifouling agent is an emulsion containing one or both of oil and wax.   The antifouling agent sprayed by the spraying method according to claim 1, wherein the antifouling agent is an emulsion containing silicone oil. The antifouling agent sprayed by the spraying method according to claim 1, wherein the antifouling agent is an emulsion containing a modified silicone oil.

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