JP2001336083A - Calendering apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a calendering apparatus to be equipped on paper manufacturing machinery, designed to obviate the stains on the paper contact surface on a shoe calender and the nonuniformity of both the smoothness and glossiness in the paper cross direction occurring on calendered paper. SOLUTION: This calendering apparatus has a roll 110 with the outermost layer provided with a porous layer 111 by ceramic thermal spraying, a tubular sleeve 113 disposed so as to countercontact with the roll 110, designed to turn round the outer circumference of a fixed center shaft 114 and having a resilient synthetic resin outer layer, and a pressure shoe 115 set up on the inner surface of the sleeve 113 and having a concave surface acting to force-press the sleeve 113 on the roll 110 via the inner surface of the sleeve 113 at the countercontact position. The calendering apparatus works as follows: a sheet of paper 107 with a specified moisture content of 3-10 wt.% is passed between the roll 110 and the tubular sleeve 113 at the countercontact positions and subjected to surface treatment with the roll 110.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a calendar processing device provided in a paper machine.

[0002]

2. Description of the Related Art In recent years, wet paper is dried by a dryer in a processing step of a papermaking machine for producing various kinds of papers, such as high-quality paper, newspaper paper, etc., from small-basis paper to large-basis paper, such as paperboard. After being processed, it is calendared. This treatment is generally performed by pressing dry paper having a moisture content of 10 to 3% against a high-temperature metal surface at a temperature of 60 to 250 ° C. and transferring the smoothness of the metal surface to the paper surface. It imparts surface properties such as smoothness and gloss to paper. As a technique for pressing the paper against a high-temperature metal surface, a general technique is to arrange a plurality of cylinders in parallel, apply a load to the shaft end, form a roll nip, and pass the paper between the nips.

The names of such nips are classified into chilled nips, soft nips, and super nip calendars according to the combination of rolls that form the nip. Here, the roll pressed against the heated metal roll is a metal roll. The soft nip is a rubber roll in which a polymer having a thickness of about 10 mm is adhered to the periphery of a metal cylinder. The super nip has a convex shoe inside, a metal roll with a metal shell is placed on the top and bottom, a cotton roll in the center, and a metal roll with this cotton roll and shoe. This is composed of five to six stages of rolls in which metal rolls heated so as to be in contact with are arranged vertically so that their central axes coincide.

Hereinafter, the chilled nip calendar, the soft nip calendar, and the super nip calendar are collectively referred to as a roll nip calendar. In these chilled nip calenders, soft nip calenders and super nip calenders, the nip width is as small as several mm to about 1 cm.
For this reason, the calendered paper having smoothness and glossiness is plastically deformed by the nip pressure, and thus becomes a paper having a reduced thickness, that is, a paper having a reduced bulk. However, paper with reduced bulk has reduced rigidity, increased density, and increased raw material costs. Therefore, a calendering method that maintains bulk before calendering even after calendering is desirable.

[0005] Here, a shoe calender (Japanese Patent No. 28090) capable of calendering while maintaining the bulk density.
No. 8, hereinafter, the shoe calender of this patent invention is referred to as "conventional shoe calender". FIG. 6 and FIG. 7 are schematic views of a shoe calendar described in such a patent publication. As shown in FIGS. 6 and 7, this shoe calendar
It consists of an upper half and a lower half. In the lower half, a cylindrical fixed beam 1 is fixedly attached to a support leg 11 for installation, and guide bars are provided on the outer circumference of the fixed beam 1 at appropriate intervals in parallel with the center axis of the cylinder. 8 are provided. A tubular sleeve 2 covering the cylindrical fixed beam 1 is supported by a guide bar 8 so as to be rotatable with a gap between itself and the peripheral surface of the fixed beam 1, and the gap is kept airtight. For this reason, both end faces are supported by the clamp desk 9.

[0006] Inside the fixed beam 1, there is provided a pressurizing chamber 13 which slidably accommodates a pressurizing shoe 3 having a concave curved surface at its tip, and this pressurizing chamber 13 supplies pressurized oil. It is connected to a hydraulic device (not shown) via the path 4, and controls the internal pressure of the pressurizing chamber 13. Since the pressure shoe 3 is in contact with the sleeve 2 under pressure, when the internal pressure of the pressure chamber 13 increases, the pressure shoe 3 presses the inner surface side of the sleeve 2 and the paper sheet Form a surface treatment area.

On the other hand, a rotatable metal roll 10 is provided in the upper half of the calendar device, and the outer peripheral surface of the metal roll 10 holds the running paper sheet 15 in the lower half of the calender. It is in opposing pressure contact with the sleeve 2. A pressure shoe 3 is located at a pressure contact portion between the metal roll 10 and the sleeve 2, and the sleeve 2 rotates around the fixed beam 1 with the rotation of the metal roll 10.
When it comes to a pressure contact position with the metal roll 10, it deforms into a concave curved surface along the outer surface shape of the metal roll 10 and the tip shape of the pressure shoe 3. Thereby, calendering can be performed while maintaining the bulk density.

[0008]

However, in the case of the above-mentioned conventional shoe calender (Japanese Patent No. 2800908), there is a problem that a paper contact surface is stained, and a smoothness and a glossiness in a calendered paper in a paper width direction. However, there remains a problem that non-uniformity occurs. Hereinafter, these problems will be described. Dirt on paper contact surface a. General stain mechanism and countermeasures When making paper using waste paper raw materials, some pulp raw materials include
It contains not a small amount of glue and ink residue from products that were not sufficiently removed. Further, in order to prevent ink bleeding during printing, a sizing agent such as rosin or wax is added as an additive to pulp before papermaking. The calendar process is performed after the drying process.

In other words, the temperature of the paper is raised to about 80 ° C. after the drying treatment, and the paper in which the internal tackiness is softened is pressed against the roll at high pressure in the nip portion of the calendar. The adhesive component adheres to the calendar roll. When the adhesive component accumulates on the calendar roll, the smoothness of the surface in contact with the paper decreases, resulting in a decrease in the smoothness and gloss of the paper after the calendar processing. for that reason,
Paper manufacturers regularly shut down their paper machines and clean the surfaces of their calendar rolls.

The frequency varies considerably depending on the type of paper, such as twice a day when making paperboard made of waste corrugated cardboard and once every three months to half a year when making high quality paper having a small amount of adhesive component. For this reason, suppressing the adhesion of the adhesive component to the surface in contact with the paper, and facilitating the removal of the adhesive component from the roll on which the adhesive component is deposited, maintain the calendar performance during papermaking, and This is important in terms of preventing productivity deterioration due to machine shutdown.

B. A dirt on a conventional shoe calender A feature of a conventional shoe calender (Japanese Patent No. 2800908) is that calendering can be performed while maintaining bulk density by applying a concave-curved shoe to the calender. For this reason, the shoe calender has a water content of 10 to 50 mm in the papermaking direction by a pressure shoe having a width of 50 to 400 mm.
３3% paper on heated metal roll surface, linear pressure 60 ~
Pressure contact is performed at about 500 kN / m. In the case of a roll nip calendar, the nip width in the papermaking direction is about several mm. On the other hand, Patent No. 2800 with an increased nip width
It can be seen that the contact time between the paper and the heated surface in the Shoe calender No. 908 is nearly 100 times longer than in the roll nip calender.

The heating surface temperature is 200 ° C. and the paper making speed is 120
FIGS. 5 (a) and 5 (b) show calculation results obtained by simulating the temperature change in the nip portion of the conventional shoe calender and the conventional roll nip calender at 0 m / min, respectively. FIG. 5 (a),
The horizontal axis in (b) shows the contact time from the nip entrance. In (a) and (b), the scale of the contact time on the horizontal axis is changed in accordance with the actual contact time, and the shoe calendar has a much longer paper contact time than the roll nip calendar. Since the length is longer, the scale is different, but the slope of each characteristic line can be compared as it is.

Although z / c is shown in FIG.
Indicates the coordinates in the paper thickness direction with the origin being the contact position between the metal roll surface and the paper, c indicates the paper thickness, and z / c is the ratio of the distance in the paper thickness direction to the paper thickness. The three solid lines indicate that the ratio of the distance in the paper thickness direction to the paper thickness in order from the top is 0.
The paper temperature changes at 1, 0.5, and 0.9 are shown.
From FIGS. 5A and 5B, it can be seen that the temperature of the shoe calender of Japanese Patent No. 2800908 significantly increases only in the paper layer in contact with the heating surface, as compared with the roll nip calender.

As a result, the higher the paper temperature, the softer the adhering component. Therefore, if the shoe calender disclosed in Japanese Patent No. 2800908 is continuously calendered, the adhesive component adheres to the surface of the metal roll to cause contamination. In addition to this, the paper temperature is as high as about 180 ° C. only in the paper layer in contact with the heating surface, so that the paper fibers adhere to the heating surface, causing “burn-in” of the fibers on the metal roll surface.

As described above, in the conventional shoe calendar,
There is a problem that contamination on the surface of the metal roll is larger than that of the roll nip calendar. c. Difficulty of Removing Soil in Conventional Shoe Calender By the way, in a roll nip calender, each roll is provided with a doctor for scraping an adhesive component from the roll. However, as shown in FIG. 6, in the case of Japanese Patent No. 2800908, there is no place in the pressurizing mechanism that can withstand the nip pressure of the doctor. Therefore, even if the tubular sleeve 2 is pressed by a doctor on the guide member to try to scrape the adhesive component, the tubular sleeve 2 is easily deformed. As a result, it is difficult to remove the adhesive component uniformly in the roll width direction. As described above, in the conventional shoe calender, the nip passage time is long, and thus the metal roll 1 is not provided as shown in FIG.
Only the paper layer in contact with 0 heats significantly. For this reason, not only the adhesive component of the paper 15 adheres to the metal roll surface 10 but also the smoothness in the paper width direction on the paper after the calendar processing.
Non-uniformity such as glossiness occurs.

The tubular sleeve 2 orbits around the fixed beam 1 in a substantially cylindrical shape, but its shape changes at the nip. In the initial portion of the nip, since the pressure shoe 3 is concave, the tubular sleeve 2 is subjected to a deforming action in a direction opposite to the cylindrical shape at the time of rotation. After this, the tubular sleeve 2
Gradually converges and conforms to the shape of the pressure shoe 3 at the end of the nip. Since the tubular sleeve 2 is pressed against the metal roll 10 at a maximum of 5 MPa by the pressure shoe 3, when the tubular sleeve 2 is deformed, a force in the paper width direction acts on the paper due to friction with the paper.

Then, as shown in FIG. 5 (a), the temperature of the paper layer in contact with the metal roll 10 increases at a steep gradient in the initial portion of the nip. As described above, in the initial portion of the nip, a force in the paper width direction due to the deformation of the tubular sleeve 2 acts on the heated paper fiber, resulting in non-uniformity in the paper width direction after calendering. For example, a paper fiber that receives a tensile force in the paper width direction loses contact with a metal surface due to partial elongation, and the contact surface becomes a portion where smoothness and glossiness are lost. Conversely, the paper fiber compressed in the paper width direction excessively contacts the metal surface, and the contact surface becomes a portion having excessive smoothness and gloss.

Further, in the conventional shoe calender, as described above, dirt on the surface of the metal roll tends to be large, and such dirt does not usually spread uniformly on the surface of the metal roll. Therefore, such dirt on the surface of the metal roll also causes non-uniformity in the width direction of the paper after the calendar processing. SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and eliminates the contamination of the paper contact surface of the conventional shoe calendar as described above and the unevenness in the smoothness and gloss in the paper width direction of the calendered paper. An object of the present invention is to provide a calendar device that can be used.

[0019]

For this purpose, a calendar device according to the present invention (Claim 1) is provided with a roll having a porous layer formed on the outermost layer by ceramic spraying, and is arranged so as to face and contact the roll. A tubular sleeve that rotates around the outer periphery of the fixed center shaft, and a concave curved surface that is disposed on the inner surface of the tubular sleeve and presses the tubular sleeve against the roll from the inner surface of the tubular sleeve at the opposed contact position. With a pressure shoe that has
A paper having a predetermined moisture content is passed between the roll and the tubular sleeve at the opposing contact position to perform surface treatment with the roll.

It is preferable that the tubular sleeve has an outer layer made of an elastic synthetic resin. It is preferable that the porous layer contains Al ₂ O ₃ as a main component. Further, the temperature of the roll on which the porous layer is formed is preferably 60 ° C to 350 ° C, more preferably 60 ° C to 250 ° C (Claim 4). further,
A doctor for removing dirt adhering to the outer surface of the tubular sleeve is provided (claim 5), and an arc-shaped guide is provided on the inner surface of the tubular sleeve so as to face the doctor. (Claim 6). Further, the pressure shoe may be divided in the paper width direction.

[0021]

Embodiments of the present invention will be described below with reference to the drawings. First, a first embodiment will be described. FIGS. 1 and 2 show a calendar device (shoe calendar) as a first embodiment of the present invention.
Is a schematic cross-sectional view (transverse cross-sectional view), and FIG. 2 is a schematic front view (partial schematic vertical cross-section).

As shown in FIG. 1 and FIG. 2, a calendar device (hereinafter referred to as a shoe calendar) 100 of the present embodiment
It is provided with a roll 110 and a pressurizing section 101 having a tubular sleeve 113 arranged so as to face the roll 110. A nip 112 is formed between the roll 110 and the tubular sleeve 113 of the pressurizing unit 101 at the opposing contact position so that the paper 107 having a moisture content of 3 to 10% passes through the nip 112. Has become. The paper 1 is pressed by a pressure shoe 115 having a concave curved surface described later provided inside the pressure section 101.
07 is pressed against the high-temperature porous layer 111, and the paper surface 108 passing through the nip 112 is subjected to calendar processing (surface processing).

The roll 110 has an outermost layer of Al ₂
Porous layer 1 by ceramic spraying mainly composed of O ₃
11 are formed. 1 and 2, the thickness of the porous layer 111 is enlarged for convenience. Thus, the surface of the roll 110 having the porous layer 111 is desirably polished to a maximum roughness of about 3.2S. Also, the roll 110 is about 60 ° C. to 350 ° C.,
More preferably, it is heated to about 60 ° C to 250 ° C. As a heating device for the roll, a heating means using induction heating or a heat medium oil may be provided inside the roll 110, or an external heating means such as a dielectric heating device or a combustor may be provided outside the roll 110. Such a heating means is publicly known and is not shown here.

The pressurizing section 101 mainly includes the center shaft 1
14, a pressure shoe 115, and a tubular sleeve 113. The center shaft 114 is fixed,
The tubular sleeve 113 goes around the center shaft 114 via a bearing 136. On the roll 110 side of the center shaft 114, a pressing shoe 115 having a concave pressing surface is provided. Pressure shoe 11
The nip portion 112 is formed between the tubular sleeve 113 pressed against the roll 110 under the pressure of 5 and the roll 110 (the above-mentioned opposing contact position).

The pressing shoe 115 has a width of 50 to 50, for example.
It is 400 mm, and the contact surface with the tubular sleeve 113 is a concave curved surface along the shape of the roll 110. Further, the pressure shoe 115 is provided with several pockets 115 a on the contact surface side with the tubular sleeve 113.
Pressurized oil pressurized by an external device (not shown) is supplied to the pocket 115a from pressurized oil supply paths 117 and 118.

As described above, an oil film is formed between the tubular sleeve 113 and the press shoe 115 by pressurized oil, so that seizure between the press shoe 115 and the tubular sleeve 113 can be prevented. . However, at high speeds, the oil film thickness may decrease at the initial portion of the pressure shoe 115, so that lubricating oil is supplied from the lubricating oil supply passage 116 to the nip inlet 112.

Further, doctors 124 and 125 are provided on the outer periphery of the roll 110 and the pressurizing section 101, respectively, for removing dirt such as adhesive components adhering to the outer surfaces thereof. The doctor 12 of the pressing unit 101 is provided on the pressing unit 101 side.
5 to provide back support
The guide 121 having an arc-shaped contact surface along the inner peripheral surface of No. 3
Is installed. When the guide 121 is installed in this way, the pressurized oil is supplied to the guide 121 from the pressurized oil supply path 122 and the lubricating oil is supplied to the guide 121 from the lubricating oil supply path 123.

The pressurized oil and lubricating oil supplied from each supply path are supplied to the tubular sleeve 113 by the wiper 120.
It is scraped off from the inner surface, collected from the lubricating oil and pressurized oil collecting unit 119, and sent from the lubricating oil and pressurized oil collecting passage 137 to an external device (not shown). Therefore,
The guide 121 is turned into a tubular sleeve 113 by pressurized oil.
The urging force is urged toward the inner surface, and the urging force back-supports the doctor 125 of the pressurizing unit 101.
To lubricate the sliding.

The tubular sleeve 113 is made of a resin having a high maximum operating temperature (heat-resistant temperature), and has an elastic synthetic resin layer as an outer layer. The outer surface of the tubular sleeve 113 in contact with the paper surface 109 has a maximum roughness of 25.
It is desirable to have S smoothness. Since the calendar device as the first embodiment of the present invention is configured as described above, as described below, in the shoe calendar,
It is possible to prevent (reduce) adhesion of an adhesive component or the like to the roll 110 and the tubular sleeve 113, and to prevent (reduce) non-uniformity in calendar processing in the paper width direction that occurs on paper after the calendar processing. Can be.

First, improvement of non-uniformity in the paper width direction and reduction of stains on the roll 110 will be described. Roll 1 in a conventional shoe calendar (Japanese Patent No. 2800908)
The increase in the amount of adhesion of the adhesive component or the like to the tube 10 and the tubular sleeve 113 is caused by the fact that only the paper layer in contact with the high-temperature metal roll is heated, as shown in FIG. In contrast, in the calender device, the roll 110 by a ceramic spraying the outermost layer forms a porous layer 111 having a thickness of 10~500μm mainly composed of Al ₂ O _3, or the like, of Al ₂ O ₃ or the like From the surface structural characteristics of ceramic,
The temperature rise of the paper layer in contact with the roll 110 is suppressed.

That is, on the surface of the porous layer 111 made of ceramics such as Al ₂ O ₃ , a large number of extremely fine holes are formed.
The heat conduction to the heat is very low. Therefore, the temperature of the sheet 108 does not rise sharply, and
If the time for the sheet 8 to pass through the outer periphery of the roll 110 (the surface of the porous layer 111) does not become excessive, the temperature of the paper surface 108 does not rise excessively.

The heating surface temperature was 200 ° C., and the papermaking speed was 120.
FIG. 5C shows a calculation result obtained by simulating a change in the paper temperature at the nip portion of the shoe calender according to the present invention having the porous layer 111 on the roll surface at 0 m / min.
Shown in The horizontal axis in FIG. 5C indicates the contact time from the nip entrance. Also, z / c is shown in FIG. 5, z indicates the coordinates in the paper thickness direction with the origin being the contact position between the metal roll surface and the paper, c indicates the paper thickness, and z / c indicates the paper thickness. This is the ratio of the directional distance to the paper thickness. In FIG. 5C,
The three solid lines show the paper temperature change when the ratio of the distance in the paper thickness direction to the paper thickness in order from the top is 0.1, 0.5, 0.9.

When comparing FIG. 5 (a) and FIG. 5 (c),
The shoe calender of the present device having the porous layer 111 on the roll surface has an extremely small gradient of the paper temperature at the nip initial portion and a heated surface at the nip end portion, as compared with the shoe calender of Japanese Patent No. 2800908. It can be seen that the temperature of the paper layer in contact is suppressed to the same level as the roll nip calendar.

As a result, the shoe calender of the present apparatus does not raise the temperature of the paper fiber in the initial portion of the nip. Therefore, even if a force in the paper width direction acts on the paper fiber due to the deformation of the tubular sleeve 2, the calender after the calendering process is performed. No unevenness such as smoothness and glossiness in the width direction of the paper occurs. In addition, since the temperature of the paper layer in contact with the heating surface is suppressed, the contamination due to the adhesion of the adhesive component or the like to the roll 110 can be reduced to the level of a roll nip calendar. In addition, the surface of the porous layer 111 made of ceramic such as Al ₂ O ₃ has extremely good releasability, and in this respect, the effect of preventing adhesion of the adhesive component to the roll 110 is high.

The present apparatus also has an advantage that dirt can be easily removed in the pressurizing section 101. That is, in the shoe calendar of the present invention, as shown in FIG. 1, a guide 121 having an arc-shaped contact surface is installed at a position opposite to the pressing shoe 115, and this arc-shaped guide 121 becomes a back support of the doctor 125. Therefore, in the shoe calendar of the present invention,
This enables uniform removal of the adhesive component in the paper width direction.

Next, the second embodiment will be described. FIG. 4 is a schematic front view (partial schematic vertical cross section).
4, the same reference numerals as those in FIGS. 1 and 2 denote the same members, and a description thereof will be omitted. If the deflection of the center shaft 114 caused during pressurization occurs, the paper 107 passing through the calendar device is likely to be unevenly pressurized in the width direction, which may cause unevenness in smoothness and gloss in the paper width direction. is there. For example, as shown in FIG. 3, the pressing force may increase in the vicinity of both ends in the width direction of the paper 107. In this embodiment, the pressure shoes 130 to 133 are divided into a plurality of pieces in the paper width direction in order to correct the deflection of the center shaft 114 which occurs at the time of pressurization as shown in FIG. It is provided. Here, four pressure shoes 130 to 133 are provided, but an appropriate number may be provided. As in the first embodiment, several pockets 130a to 133a are provided on each of the pressure shoes 130 to 133 on the contact surface side with the tubular sleeve 113.

Since the calendar device of the second embodiment is configured as described above, the center shaft 1 generated at the time of pressurization is formed.
The pressure applied by the pressure shoe 133 is increased at a portion where the pressure is reduced due to the deflection of the center 14, and the pressure applied by the pressure shoe 133 is reduced at a portion where the pressure is increased due to the deflection of the center shaft 114 generated at the time of pressurization. In this way, uniform pressing can be performed in the width direction of the paper 107, which is effective in eliminating unevenness in smoothness and gloss in the paper width direction.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and can be variously modified and implemented without departing from the gist of the present invention. For example, the ceramic of the material of the porous layer 111 is not limited to those mainly composed of Al ₂ O ₃ , but may be Ti _2.
Other ceramic O _X and the like may be obtained by mainly. Of course, it is preferable that the ceramic used has low surface thermal conductivity and high releasability. Tubular sleeve 11
3 preferably has an outer layer made of an elastic synthetic resin having a high heat-resistant temperature as in the present embodiment, whereby the nip width can be secured at low cost while ensuring durability. It is not limited to such a configuration as long as it can ensure the above.

Depending on how the outer surfaces of the roll 110 and the tubular sleeve 113 are contaminated, the doctor 124,
It is conceivable that 125 is not always necessary, and in such a case, one or both of the doctors 124 and 125 may be omitted. When the doctor 125 is omitted, the guide 121 is naturally unnecessary. The moisture content of the paper is generally 3
-10%, but is not necessarily limited to this.

[0040]

As described above in detail, according to the calendar device of the first aspect of the present invention, the surface of the roll (outermost layer)
Since the porous layer is formed by ceramic spraying on the surface, using the low thermal conductivity and high releasability of the ceramic, the stain on the paper contact surface in the shoe calendar,
It is possible to eliminate unevenness in smoothness and glossiness in the width direction of the paper that occurs in the paper that has been subjected to the calendar processing.

In particular, since the tubular sleeve 113 has an outer layer made of an elastic synthetic resin, the nip width can be reliably ensured at low cost, and a desired calendar performance can be obtained. The above effect can be reliably obtained by forming the porous layer with Al ₂ O ₃ as a main component which sufficiently satisfies the point of low thermal conductivity and the point of high releasability of the ceramic (claim 3). Further, by providing a doctor for removing dirt attached to the outer surface of the tubular sleeve, it is possible to promote smoothness and unevenness of glossiness in the width direction of the paper (claim 5).
By disposing the arc-shaped guide so as to face the doctor, the elimination of such unevenness can be further promoted (claim 6). Also, by dividing the pressure shoe in the paper width direction, it is possible to promote the elimination of unevenness in smoothness and gloss in the paper width direction.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view (transverse sectional view) showing a calendar device (shoe calendar) as a first embodiment of the present invention.

FIG. 2 is a schematic front view (partially schematic vertical section) showing a calendar device (shoe calendar) as a first embodiment of the present invention.

FIG. 3 is a diagram showing a pressure characteristic applied to a calendar device (shoe calendar) as a second embodiment of the present invention, showing an example in which the pressing force of paper is not uniform in the width direction of paper.

FIG. 4 is a schematic front view (a partial schematic vertical section) showing a calendar device (shoe calendar) as a second embodiment of the present invention.

5A and 5B are graphs showing the problems of the prior art and the effects of the present invention. FIG. 5A is a diagram showing a change in paper temperature at a nip portion of a conventional calendar device (shoe calender), and FIG. FIG. 4 is a diagram showing a change in the paper temperature at the nip portion of the device (roll nip calender), and FIG. 4C is a diagram showing a change in the paper temperature at the nip portion of the calendar device (shoe calender) of the present invention.

FIG. 6 is a schematic sectional view (transverse sectional view) showing a conventional calendar device (shoe calendar).

FIG. 7 is a schematic front sectional view (transverse sectional view) showing a conventional calendar device (shoe calendar).

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Cylindrical fixed beam 2 Tubular sleeve 3 Pressurizing shoe 4 Pressurized oil supply path 5 Lubricating oil supply path 6 Lubricating oil recovery path 7 Lubricating oil discharge path 8 Guide bar 9 Clamp desk 10 Metal roll 11 Support leg 13 Pressurizing chamber 15 Paper sheet 101 Pressing section 107 Paper 108, 109 Paper surface 110 Roll 111 Porous layer 112 Nip section 113 Tubular sleeve 114 Center shaft 115 Pressing shoe 115a Pocket 116 Lubricating oil supply path 117, 118 Pressurized oil supply path 119 Lubricating oil , Pressurized oil recovery section 120 wiper 121 guide 122 pressurized oil supply path 123 lubricating oil supply path 124, 125 doctor 130-133 pressure shoe 130a-133a pocket 136 bearing 137 lubricating oil, pressurized oil recovery path

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Akira Sanada 5007 Itozakicho, Mihara City, Hiroshima Prefecture Mitsubishi Heavy Industries, Ltd.Paper & Printing Machinery Division (72) Inventor Toshiyuki Toshiyuki 5007 Itozakicho, Mihara City, Hiroshima Prefecture Mitsubishi Heavy Industries Koji Kaneko, Inventor Koji Kaneko 5007, Itozakicho, Mihara-shi, Hiroshima Mitsubishi Heavy Industries, Ltd. F-term (Reference) 4L055 CG04 CG06 CG12 CH02 FA12 FA14 FA20

Claims (7)

[Claims] 1. A roll having a porous layer formed on the outermost layer by ceramic spraying, a tubular sleeve arranged so as to face the roll and rotating around a fixed center shaft, and a tubular sleeve. A pressure shoe disposed on an inner surface of the sleeve and having a concave curved surface for pressing the tubular sleeve against the roll from the inner surface of the tubular sleeve at the opposed contact position; A calender, characterized in that a paper having a predetermined moisture content is passed between a sleeve and a surface of the calender to perform surface treatment with the roll. 2. The calendar device according to claim 1, wherein the tubular sleeve has an outer layer made of an elastic synthetic resin. 3. The calendar device according to claim 1, wherein the porous layer contains Al ₂ O ₃ as a main component. 4. The method according to claim 1, wherein the temperature of the roll on which the porous layer is formed is 60 ° C. to 350 ° C., preferably 60 ° C. to 250 ° C. Calendar device. 5. The calendar device according to claim 1, further comprising a doctor for removing dirt adhering to the outer surface of the tubular sleeve. 6. The calendar according to claim 1, wherein an arc-shaped guide is provided on the inner surface of the tubular sleeve so as to face the doctor. apparatus. 7. The calendar apparatus according to claim 1, wherein said pressure shoe is divided in a paper width direction.