WO2011115013A1

WO2011115013A1 - Method for adjusting curl of coated paper

Info

Publication number: WO2011115013A1
Application number: PCT/JP2011/055784
Authority: WO
Inventors: 弘幸河野; 敏弘片野
Original assignee: ボイスパテントゲーエムベーハー
Priority date: 2010-03-18
Filing date: 2011-03-11
Publication date: 2011-09-22
Also published as: JP2011195980A; EP2549014A4; CN102803608A; EP2549014A1

Abstract

A method for adjusting the curl of coated paper, which includes a process for applying coating to one side of a web (W) to be conveyed, and drying the coating with a dryer, and a process for applying the coating to the other side of the web, and drying the coating with the dryer so as to be provided at the time of producing the coated paper formed by applying the coating to the one side and the other side of the web, wherein, in the heating temperature in a last dryer (6B4) through which the web to which the last coating has been applied at the time of producing the coated paper passes, a heating temperature to a reverse coated surface (Wa) of the web to which the last coating has not been applied is set lower than a heating temperature to a coated surface (Wb) of the web to which the last coating has been applied.

Description

Curling adjustment method for coated paper

The present invention comprises the steps of applying a paint to one side of a web to be transported, drying the paint with a dryer, and applying a paint to the other side of the web, and drying the paint with a dryer. The present invention relates to a method for adjusting the curl of a coated paper for adjusting and correcting the curl that occurs on the coated paper at the time of producing a coated paper comprising the coating on one side and the other side of the web. It is.

For example, as a coating facility for producing coated paper such as art paper or coated paper obtained by applying paint to both sides of a web (base paper), the paint is applied to one side of the web to be conveyed, and the paint is applied. After drying with a hot air drier or the like, the other surface of the web is coated with a paint, and the paint is dried with a hot air drier or the like to coat both sides (one side and the other side) of the web. Coating equipment configured as described above is provided (see, for example, Patent Document 1 and Patent Document 2).

FIG. 4 shows an example of a conventional coating installation for producing the above-mentioned coated paper. In this coating installation A, the web W delivered from the delivery roll Rf is firstly subjected to the first coating section C1. A predetermined amount of paint pa (see FIG. 3B) is applied to one surface Wa by being wound around a backing roller Ba, and by a coating machine (blade type coating machine) Ca.

Next, the web W is fed into the first drying unit H1, and passes the first to fourth dryers h1, h2, h3, h4 arranged in parallel along the transport direction of the web W, thereby Drying is performed on the paint pa.

Here, the first to fourth dryers h1, h2, h3 and h4 are hot air dryers for blowing hot air from above and below the web W, and the web W is coated with a paint pa. The above-described dryers h1, h2, h3 and h4 are sequentially passed in a posture in which the one surface Wa is up.

The web W having passed through the first drying unit H1 is then wound around a backing roller Bb in a second coating unit C2, and is applied to the other surface Wb by a coating machine (blade type coating machine) Cb. A predetermined amount of paint pb (see FIG. 3 (b)) is applied to it.

Next, the web W is fed into the second drying unit H2, and passes the first to fourth dryers h1, h2, h3, h4 arranged in parallel along the transport direction of the web W, as described above. Drying is performed on the paint pb.

Here, the first to fourth dryers h1, h2, h3 and h4 are hot air dryers for blowing hot air from above and below the web W, and the web W is coated with a paint pb. The above-mentioned dryers h1, h2, h3 and h4 are sequentially passed in a posture in which the other surface Wb is turned up.

As described above, the paint pa is applied to the one surface Wa of the web W by passing through the first coating unit C1, the first drying unit H1, the second coating unit C2, and the second drying unit H2. A coated paper P (see FIG. 3 (b)) which is finished and coated with the paint pb on the other surface Wb of the web W is manufactured, and the coated paper P as a product is wound on a winding roll Rt. It will be.

Japanese Patent Application Publication No. 06-235197 JP 2001-246306 A

By the way, when manufacturing coated paper P in coating installation A as mentioned above, the process which dries paint pb applied to other side Wa of web W, ie, paint pb applied at the end to web W In the step of drying, there is a disadvantage that a slight curl (warpage deformation) may occur such that the coating pb side of the web W (coated paper P) is recessed.

This is because, as shown in FIG. 3 (b), in the dryer h4 at the end of the second drying unit H2, the hot air fu at 250 to 300 ° C. from the upper unit h4u and the lower unit h41 like the other dryers. , Fu ... and hot air fl, fl ... are sprayed, so that only the paint pb and the paper surface which are applied to the other surface Wa of the web W and still wet are forcibly dried by the hot air in the dryer h4. It is thought that it is generated by being

In view of the above situation, the present invention applies a paint to one side of a web, dries the paint with a drier, then applies a paint to the other side of the web, and dries the paint with a drier The purpose of the present invention is to provide a method for adjusting the curl of coated paper, which can be adjusted and corrected for curling of the coated paper when producing coated paper obtained by applying the coating on both sides of the web. And

In order to achieve the above object, the method for adjusting a curl of a coated paper according to the invention of claim 1 comprises the steps of: applying a paint to one side of a conveyed web; and drying the paint by a dryer; Coating the other side with a coating, and drying the coating with a dryer, and adjusting the curl of the coated paper at the time of production of the coated paper formed by applying the coating on the one side and the other side of the web A method wherein the heating temperature in the last dryer through which the last paint applied web passes during the manufacture of the coated paper is greater than the heating temperature for the coated surface of the last paint applied web It is characterized in that the heating temperature for the opposite coated surface of the web to which the last paint is not applied is set low.

According to the method for adjusting curl of coated paper according to the invention of claim 1, the curling of the coated paper is set by setting the heating temperature for the non-coated surface of the web lower than the heating temperature for the coated surface of the web. It becomes possible to adjust and correct | amend flatly.

BRIEF DESCRIPTION OF THE DRAWINGS The conceptual whole view which shows an example of the coating installation to which the curl adjustment method of the coated paper which concerns on this invention is applied. The principal part conceptual diagram of the coating installation shown in FIG. (a) is sectional drawing of the dryer and coated paper of the drying part in the coating installation shown in FIG. 1, (b) is sectional drawing of the dryer and coated paper of the drying part in the conventional coating installation. The conceptual general view which shows the conventional coating installation.

Hereinafter, the method for adjusting curl of coated paper according to the present invention will be described in detail with reference to the drawings showing the examples.

FIG. 1 shows an example of a coating installation to which the method for adjusting curl of coated paper according to the present invention is applied, and the coating installation in this embodiment is applied to one side and the other side of a web (base material) It is a coating facility for producing coated paper in which two layers of paint are applied one on top of the other.

In the coating facility 1, the web W fed out from the delivery roll 2f is first wound around the backing roller 3Ar in the first coating section 3A, and the coating machine (blade type coater) 3Ac The first layer paint pa1 (see FIG. 3A) is applied to the area Wa.

Next, the web W is fed into the first drying unit 4A, and passes the first to fourth dryers 4A1, 4A2, 4A3, 4A4 arranged in parallel along the transport direction of the web W. Drying for the paint pa1 will be carried out.

The first to fourth dryers 4A1, 4A2, 4A3, 4A4 are hot-air dryers that blow hot air of 250 to 300 ° C. from the upper side and the lower side to the web W being transported, and the web W is The above-mentioned dryers 4A1, 4A2, 4A3, 4A4 are sequentially passed in a posture in which the one surface Wa coated with the paint pa1 is turned up.

The web W having passed through the first drying unit 4A is then wound around the backing roller 3Br in the second coating unit 3B, and is applied to the other surface Wb by the coating machine (blade type coating machine) 3Bc. On the other hand, the first layer paint pb1 (see FIG. 3A) is applied.

Next, the web W is fed into the second drying unit 4B, and passes the first to fourth dryers 4B1, 4B2, 4B3, 4B4 arranged in parallel along the transport direction of the web W. Drying of the paint pb1 is to be carried out.

The first to fourth dryers 4B1, 4B2, 4B3, 4B4 are hot-air dryers that blow hot air of 250 to 300 ° C. from the upper side and the lower side to the web W being transported, and the web W is The above-mentioned dryers 4B1, 4B2, 4B3, 4B4 are sequentially passed in a posture in which the other surface Wb to which the paint pb1 is applied is turned up.

By passing through the first coating unit 3A, the first drying unit 4A, the second coating unit 3B, and the second drying unit 4B described above, the paint of the first layer is applied to the one surface Wa of the web W pa1 is applied, and the other layer Wb of the web W is coated with the first layer paint pb1.

The web W having passed through the second drying unit 4B is then wound around the backing roller 5Ar in the third coating unit 5A, and is applied to one surface Wa by a coating machine (blade type coating machine) 5Ac. A second layer paint pa2 (see FIG. 3A) is applied so as to cover the first layer paint pa1.

Next, the web W is fed into the third drying unit 6A, and passes the first to fourth dryers 6A1, 6A2, 6A3, 6A4 juxtaposed along the transport direction of the web W. Drying for the paint pa2 will be performed.

The first to fourth dryers 6A1, 6A2, 6A3, 6A4 are hot-air dryers that blow hot air of 250 to 300 ° C. from the upper side and the lower side to the web W being transported, and the web W is The above-mentioned dryers 6A1, 6A2, 6A3, 6A4 are sequentially passed in a posture in which the one surface Wa to which the paint pa2 is applied is turned up.

The web W passed through the third drying unit 6A is then wound around the backing roller 5Br in the fourth coating unit 5B as shown in FIGS. The second layer paint pb2 (see FIG. 3A) is applied by the 5Bc toward the other surface Wb so as to cover the first layer paint pb1.

Next, the web W is fed into the fourth drying unit 6B, and passes the first to fourth dryers 6B1, 6B2, 6B3, 6B4 arranged in parallel along the transport direction of the web W, thereby Drying of the paint pb2 is to be carried out.

The first to fourth dryers 6B1, 6B2, 6B3 and 6B4 are hot air dryers for blowing hot air from the upper side and the lower side to the web W being conveyed, and the web W is the one of the paint pb2 The above-mentioned dryers 6B1, 6B2, 6B3 and 6B4 are sequentially passed in a posture in which the other surface Wb applied is turned up.

Here, while the first to third dryers 6B1, 6B2, 6B3 blow hot air of 250 to 300 ° C. from the upper side and the lower side with respect to the web W being conveyed, In the dryer 6B4, the hot air of 300.degree. C. is blown from above to the web W, while the hot air of 65.degree. C. is blown from below to the web W.

By passing through the third coating unit 5A, the third drying unit 6A, the fourth coating unit 5B, and the fourth drying unit 6B described above, the first layer is formed on the one surface Wa of the web W described above. The second layer paint pa2 is applied to cover the second paint layer pa1 and the second layer paint pb2 is applied to the other surface Wb of the web W covering the first layer paint pb1. .

That is, as described above, after passing through the first coating unit 3A, the first drying unit 4A, the second coating unit 3B, and the second drying unit 4B, the third coating unit 5A, the third coating unit 5A, and the third coating unit 5B are further performed. The first coating pa1 and the second coating pa2 are applied to the one surface Wa of the web W through the drying section 6A, the fourth coating section 5B, and the fourth drying section 6B. And the coated paper P (see FIG. 3 (a)) in which the first paint pb1 and the second paint pb2 are applied to the other surface Wb of the web W is manufactured, and coated paper as a product P is taken up by the take-up roll 2t.

By the way, as described above, the fourth dryer 6B4 in the fourth drying unit 6B, in other words, the last dryer 6B4 through which the web W passes when producing the coated paper P, is shown in FIG. As described above, hot air fu, fu ... of 300 ° C is blown from above to the web W, while hot air fl, fl ... of 65 ° C is blown from below to the web W.

That is, in the dryer 6B4, the heating temperature (300 ° C.) with respect to the coated surface of the web W coated with the last paint pb2 at the time of manufacturing the coated paper P, ie, the other surface Wb of the web W in the example. The heating temperature (65 ° C.) with respect to the opposite coated surface of the web W not coated with the last paint pb 2, that is, one surface Wa of the web W in the example, is set low. It has been confirmed at the time of actual production that the curling of the sheet is adjusted and corrected to a flat plate shape.

Here, when the web W is conveyed to the fourth drying unit 6B through the fourth coating unit 5B, 300 ° C. hot air fu blown from the upper unit 6B 4 u in the fourth dryer 6B4. As a result, the periphery of the web W is heated to a high temperature (about 300 ° C.), and a large amount of water vapor from the paint pb2 applied to the other surface Wb (coated surface) of the web W is contained.

In such an atmosphere, when hot air fl at a temperature of 65 ° C., which is lower than the hot air fu from the upper unit 6B 4 u, is blown from the lower unit 6 B 4 l to the one surface Wa (anti-coated surface) of the web W The temperature of the direction Wa (non-coated surface) falls, and condensation occurs when the air around the high temperature and humidity gets in contact with the one surface Wa (non-coated surface), and the water content on the one surface Wa (non-coated surface) increases. It will be.

After this, with the conveyance of the web W, the upward curl when the paint pb2 on the other surface Wb (coated surface) is dried by the hot air fu from the upper unit 6B4u, and the hot air fl from the lower unit 6B4l The curling of the web W (coated paper P) is adjusted by offsetting the downward curling when the water on the (coated surface) evaporates, and the web W (coated paper corrected in a flat plate shape) P) can be obtained.

Here, as described above, in the fourth dryer 6B4, an increase in the amount of water due to condensation occurs on one surface Wa (the non-coated surface) of the web W, and then in the air in the final transport area 1e shown in FIG. The same function and effect (curling correction) can be obtained by naturally drying the water of the one surface Wa (the opposite coating surface) while transporting the web W.

In the fourth dryer 6B4, the heating temperature for the coated surface (the other surface Wb) of the web W is effective in the range of 300 to 400 ° C., and the heating temperature for the non-coated surface (the one surface Wa) of the web W Although the range of 65 to 70 ° C. is also effective, as the difference between the heating temperature for the coated surface of the web W and the heating temperature for the non-coated surface is larger, the tendency is that curls are more effectively adjusted. It is effective to set the heating temperature for the coated surface (the other surface Wb) of the web W to 400 ° C. and the heating temperature for the non-coated surface (the one surface Wa) of the web W to 65 ° C.

In the coating installation 1 shown in FIGS. 1 to 3, although the first to

fourth drying units

4A, 4B, 6A, and 6B are each composed of four dryers, each of the drying units is It goes without saying that the number of dryers constituting can be constituted by a plurality of, that is, any number of two or more.

In addition, the dryers of the drying

units

4A, 4B, 6A, 6B are all hot-air dryers, but may have a function capable of individually setting the heating temperature for one side of the web and the heating temperature for the other side. For example, various types of dryers can be employed in the drying

units

4A, 4B, 6A, 6B without being limited to the hot-air type dryer.

Furthermore, in the coating equipment 1 shown in FIGS. 1 to 3, the coated paper in which two layers of paint are applied one on another on both sides (one side and the other side) of the web W is manufactured. The coated paper according to the present invention may be any coated paper in which the same number of paint layers are formed on both sides of W, for example, when producing various papers such as art paper, coated paper, pressure-sensitive paper, paperboard, Of course, the curl adjustment method can be effectively applied.

1 ... coating equipment,
2f ... sending roll,
2t ... winding roll,
3A ... 1st coated part,
3Ac: Coating machine,
3B ... 2nd coating part,
3Bc ... coating machine,
4A ... 1st drying part,
4A1, 4A2, 4A3, 4A4 ... dryer,
4B ... 2nd drying part,
4B1, 4B2, 4B3, 4B4 ... dryer,
5A third coating unit,
5Ac: Coating machine,
5B ... 4th coated part,
5Bc ... coating machine,
6A third drying unit,
6A1, 6A2, 6A3, 6A4 ... dryer,
6B ... 4th drying part,
6B1, 6B2, 6B3, 6B4 ... dryer,
6B4u ... upper unit,
6B4l ... lower unit,
W ... Web,
Wa ... one side,
Wb: the other side,
pa1 ... the first layer of paint on one side,
pa2 ... second layer paint on one side,
pb1 ... first layer of paint on the other side,
pb2 ... second layer paint on the other side,
P: Coated paper.

Claims

Applying the paint to one side of the web to be transported, drying the paint with the dryer, and applying the paint to the other side of the web, and drying the paint with the dryer, the web A method for adjusting the curl of a coated paper at the time of producing the coated paper obtained by applying the coating on one side and the other side of
The last coating temperature is higher than the heating temperature at the coating surface of the last coating applied web, the heating temperature at the last dryer through which the last coating applied web passes during the production of the coated paper. A method for controlling curling of a coated paper, characterized in that the heating temperature for the non-coated surface of the uncoated web is set low.