JPH03206197A - Supercalender apparatus and coated paper - Google Patents

Abstract

PURPOSE:To obtain a supercalender apparatus providing plural rows of roll group in which a metal roll is combined with an elastic roll, capable of providing a coated paper having high finishing effect by subjecting web coated on one side and both faces to smoothing and gloss finishing. CONSTITUTION:In a supercalender apparatus alternately combining a metal roll with elastic roll, a combined roll group of the metal roll 1 and elastic roll 2 is arranged in two rows and tension roll 5 or dancer roll 6 are provided between roll groups in two rows to equal circumferential rate of both roll groups 9 and 10 and guide roll 4 is provided before and after a nip and coated paper 3 to which coating liquid pigment is applied using a binder is then subjected to supercalendering finish to provide the coated paper having excellent smoothness and gloss.

Description

Detailed Description of the Invention [A] Industrial Application Field The present invention relates to a supercalender device used for finishing webs coated on one side and both sides, and coated paper that has a glossy finish using the device. .

[B] Conventional technology Super calender finishing is a method for smoothing and glossing coated webs.

This is a device that alternately arranges metal rolls and elastic rolls to provide gloss and smoothness. A feature of the super calendar is that in order to obtain high nip pressure, the rolls are pressurized using hydraulic pressure, but in addition to this, there is also the advantage that pressure can be expected to be applied by the weight of the rolls themselves. Conventionally, as a super calendar device for single-sided coated paper, as shown in Fig. 4,
Metal rolls 1 and elastic rolls 2 are alternately combined, and guide rolls 4 are arranged on both sides of the roll group.

The coated paper 3 passes through the nip between the metal roll 1 and the elastic roll 2 with the coated side facing up, is turned back by the guide roll 4, and passes through the nip between the elastic roll 2 and the metal roll l.

By repeating this process, the coated surface is applied to a metal roll to obtain gloss and smoothness.

In addition, as a super calendar device for double-sided finishing,
As shown in Fig. 5, it has a structure in which metal rolls 1 and elastic rolls 2 are alternately combined, and one elastic roll called reverse roll 8 is inserted in the middle, and guide rolls 4 are arranged on both sides of the roll group. ing.

The coated paper 3 coated on both sides passes through the nip between the metal roll 1 and the elastic roll 2, is reversed by the guide roll 4, and passes through the nip between the elastic roll 2 and the metal roll 1. By repeating this process, first the upper coated surface is applied to the metal roll to achieve a glossy finish, then the reverse roll 8 and the elastic roll 2
Due to the continuous configuration, the lower coated surface is changed so as to come into contact with the metal roll 1, and the lower coated surface is finished with a gloss by subsequent metal rolls, giving the gloss and smoothness of double-sided coated paper.

[C] Problems to be solved by the invention However, the problems caused by such an alternating arrangement are as follows.
The point is that only one smearing surface hits the metal roll 1. In supercalender finishing of coated paper, the side that is in contact with the metal surface becomes glossy, while the finishing effect is reduced on the side that is in contact with the elastic roll 2.

In addition, in order to finish both sides, it is necessary to arrange one elastic roll called a reverse roll in the middle of the roll group and change the surface that contacts the metal surface.

In general super calendering for double-sided finishing, when the side of the coated paper 3 that corresponds to the metal roll 1 is changed midway through to finish both sides, the top side that has brought the finished surface to that point is transferred to the reverse roll 8. And the continuous contact of the elastic roll 2 impairs its finishing properties.

The present invention aims to solve the above-mentioned problems, and achieves the purpose by arranging roll groups in two rows in parallel, alternating the sides of the coated paper 3 that contact the rolls, and eliminating the reverse roll. It is something that becomes.

[D] Means for solving the problem, that is, the present invention is a super calender device in which metal rolls and elastic rolls are alternately combined, in which two rows of combined roll groups of metal rolls 1 and elastic rolls 2 are arranged in parallel. It is preferable that a tension roll 5 or a dancer roll 6 be provided between two rows of roll groups to make the peripheral speeds of both roll groups 9 and IO equal.

Another method for equalizing the circumferential speeds is to provide a mechanism for commonly driving the two rows of roll groups in order to make the circumferential speeds of the rolls in each row the same.

This is because in steady state operation, each roll group 9
, 10, there is no problem, but a difference in peripheral speed occurs between the roll groups 7 and 8 during acceleration/deceleration and when changing the nip pressure of the rolls. The difference in circumferential speed between roll groups (between stacks) having a plurality of alternating nips may lead to wrinkles and breakage of the coated paper 3.

Therefore, there is a draw buffering effect by the dancer roll, and speed control between the two roll groups 9 and 10 by the position of the dancer roll. Further, one or more of these dancer rolls may be changed to a tension roll to perform draw adjustment by tension control, and each of these roll groups 9,
In order to keep the circumferential speed between the rolls 10 constant, both roll groups 9
, 10 may be provided at the same time. For example, a mechanism may be provided to drive the roll groups 9 and 10 using a universal roll 7 coated with an elastic material, or a mechanism may be provided to drive the roll groups 9 and 10 using a single electric motor to drive gears, belts, chains, etc. It is also possible to drive both roll groups 9, 10 with.

Another invention relates to a coated paper characterized in that it has been given a glossy finish using a super calender device in which two rows of roll groups 9 and 10, each consisting of a metal roll 1 and an elastic roll 2, are arranged in parallel.

The coating liquid pigments used in the present invention include kaolin, calcium carbonate, clay, satin white, talc, titanium oxide, aluminum hydroxide, silica, zinc oxide, activated clay,
Acid clay, silicon clay, lake, plastic pigment,
etc.

The binder used is styrene/putadiene,
Various copolymers such as styrene/acrylic, styrene/putadiene/acrylic, vinyl acetate, ethylene/vinyl acetate, acrylic/vinyl acetate, and synthetic binders such as polyvinyl alcohol, maleic anhydride/styrene copolymers, etc. Generally known binders include oxidized starch, etherified starch, esterified starch, enzyme-modified starch, cold water-soluble starch obtained by flash drying them, heat-modified starch, casein, natural binders such as soybean protein, etc. All can be used. Moreover, various commonly used auxiliary agents such as dispersants, thickeners, water retention agents, antifoaming agents, waterproofing agents, and colorants can be used as appropriate. Further, when adjusting the coating liquid, various mixers, mixers such as sand mills, etc. are used.

By providing the roll groups 9 and 10 arranged in two rows as described above, in the case of single-sided coated paper, the coated paper 3 is first passed through the roll group 9 so that the coated side is in contact with the metal roll 1, and then It is sufficient to pass the paper through the roll group 10. In addition, in the case of double-sided coated paper, when passing through each nip, the top side of coated paper 3 is metal roll - elastic roll - elastic roll - metal roll - metal roll - elastic roll, and the bottom side is the opposite. becomes. Such an arrangement allows for the gloss treatment of single- and double-sided coated papers, avoids finishing with a continuous metal roll on only one side in the case of double-sided coated papers, and eliminates the need for reverse rolls. It became.

[E] Example The present invention will be explained in more detail based on the drawings. Note that the combined number of rolls in each stack and the roll arrangement are not limited to these and may be set as appropriate depending on the application.

Embodiment 1 FIG. 1 shows a super calender device according to an embodiment of the present invention, in which a roll group is formed by combining three metal rolls 1 and three elastic rolls 2, and this combined roll group consists of two rolls.
The rolls are arranged in parallel (roll groups 9 and 10).

Each roll group is provided with guide rolls 4 before and after the nip.

3 indicates a coated paper, and the paper is shown in a state in which the coated surface is alternately contacted with the metal roll 1 and the elastic roll 2.

Embodiment 2 In FIG. 2, a dancer roll 5 or a tension roll 6 is installed between both roll groups 9 and 10 in FIG. 1 in order to eliminate the peripheral speed difference between the roll groups 9 and 10. The dancer roll 5 can buffer differences in circumferential speed during acceleration and deceleration, which is useful for adjusting the draw of the coated paper 3.

It is also possible to adjust the speed of the rolls in each row by detecting the position of the dancer rolls 5. It is also possible to provide a tension roll 6 instead of one of these dancer rolls 5 to adjust the roll speed of each row.

Embodiment 3 FIG. 3 shows the metal roll 1 and elastic hole 2 shown in FIG.
The combined roll groups are arranged in two rows in parallel (roll groups 9 and 10), and each roll group is provided with guide rolls 4 before and after the nip, and between both roll groups 9 and 10. A universal roll 7 is provided at the bottom of the roll.

By arranging the rolls in this way, it is possible to eliminate differences in circumferential speed between the roll groups.

Example 4 and Comparative Examples The coated paper used in the example was a base paper with a basis weight of 64 g/n, and the following coating liquid was coated on both sides with a blade coater at a rate of 12 g/d on each side. It has been subjected to The finished moisture content after drying was 6%.

When the coating liquid is a pigment slurry of 80 parts of clay and 20 parts of heavy calcium carbonate, and the pigment solid content is 100 parts,
The binder was prepared by adding IO parts of SBR latex and 5 parts of phosphoric acid ester starch based on the weight of the solid content of the pigment.

The concentration of the coating solution was adjusted to 62% in terms of solid content weight concentration.

The obtained coated paper was given a glossy finish using the super calender device shown in FIG. 1 and the paper passing state.

The drive roll is at the bottom and is a fixed roll.

Pressurization was performed using hydraulic pressure at the top stage.

The hardness of the elastic roll is 86 using a spring-type D hardness tester.
It was ~88°. The temperature of each metal roll can be controlled, and each roll was adjusted to 50°C.

When the pressing force is stationary, the nip pressure at the bottom is approximately 3
The oil pressure was adjusted to 50 kg/an.

Note that the roll surface length was 100 ann, and the coated paper width was 60 ann.

In the comparative example, the paper was passed as shown in FIG. In both cases, three nips were applied to each coated surface.

In order to eliminate the difference between each roll group, roll group 9
An experiment was conducted in which the paper was fed from the roll group 10 and the paper was discharged from the roll group 10, and the paper was fed from the roll group 10 and the paper was discharged from the roll group 9, and the average of both was taken. As a matter of fact, there was no difference between the two. Note that the average value was rounded to the nearest whole number.

The experiment was conducted for cases in which the tube was passed at a speed of 6 m/min and a case where it was passed at a speed of 30 m/min. In the case of 6 m/min, samples were taken each time the nip passed, and the influence of each nip on the physical properties was investigated. At 30 m/min, samples were taken after passing through the entire nip.

The various characteristic values in the examples were measured and obtained by the following method.

1) Smoothness: Value determined by Smoostar smoothness tester (Model SM-OA, manufactured by Toei Electronics Co., Ltd.). The unit is n+mH
It is g.

2) White paper gloss: Angle 75 according to J IS8142
Every time. The unit is %.

These results are shown in Table 1.

(The following is a blank space) [F] Effects of the Invention As is clear from Table 1, the coated paper finished by the present invention has physical properties superior to the conventional finishing of one side by one continuous roll group. Something has been proven.

In other words, it has become clear that finishing in which the metal roll surface and the elastic roll surface are alternately passed through the nip multiple times using a supercalender with two rows of rolls produces a higher finishing effect.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram showing an embodiment of the present invention. FIGS. 2 and 3 are schematic diagrams showing other embodiments. FIG. 4 is a schematic diagram of a conventional single-sided finishing supercalender device. FIG. 5 is a schematic diagram of a conventional double-sided finishing supercalender device. 1: Metal roll, 2: Elastic roll, 3: Coated paper, 4: Guide roll, 5: Dancer roll, 6: Tension roll, 7: Universal roll, 8: Reverse roll,
9, 10: Roll group, 11 yen 3 rods 2 figures 3rd paper + 1 kasaku limb mouth

Claims (1)

[Scope of Claims] 1. A super calendar device comprising metal rolls and elastic rolls alternately combined, characterized in that there are two rows of combined roll groups of metal rolls and elastic rolls. 2. A supercalender device according to claim 1, further comprising a tension roll or a dancer roll between two rows of roll groups. 3. The super calender device according to claim 1, further comprising a mechanism for driving the two rows of rolls in order to make the peripheral speeds of the rolls in each row the same. 4. Two combination roll groups of metal rolls and elastic rolls
A coated paper characterized by having a glossy finish using a multi-row supercalender device.