JP3495704B2 - Paper machine for producing textured soft paper and method for producing the same - Google Patents

Abstract

A paper machine for manufacturing textured soft paper comprises a press section with a press nip, through which an impermeable belt and a felt run with the fibrous web between them, a drying cylinder and a transfer roll forming a nip for transfer of the web to the drying cylinder. According to the invention the belt is a texturing belt having a back layer and a web-contacting layer having depressions with surface portions situated between them to form a relief pattern in the web upon passage through the press nip, the texturing belt running from the press to the drying cylinder in order to carry the textured web to the transfer nip. The felt runs away from the texturing belt before a water film formed in the press nip on the texturing belt breaks up. A device is provided before the transfer nip to apply adhesive on the drying cylinder.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper making machine and a method of making paper, and more particularly to a machine and a method of making textured soft paper such as tissue.

[0002]

A paper machine for the production of tissue paper is disclosed in U.S. Pat. No. 5,393,384, see in particular FIG. The paper machine shown in the figure has an impermeable belt, which runs in a loop through an extended press nip formed by a shoe press roll and a counter roll. The press felt is conveyed directly to the press nip, which is brought with the water impermeable belt and the paper web. The paper web is transferred from the forming fabric to a water impermeable belt, which conveys the paper web on its underside to the press nip and then to the drying cylinder. Thus, after the paper web has been transferred from the forming fabric to the water impermeable belt, the water impermeable belt conveys the paper web a relatively long distance. Therefore, there is a risk that the paper web will not stick sufficiently strongly along the entire distance, and thus will come off the impermeable belt. According to the specification of the above patent, the adhesive force between the impermeable belt and the paper web is greater than the adhesive force between the press felt and the paper web. The impermeable belts under discussion in that patent are not compressible and have a smooth web transport surface.

As the belt, press felt and paper web pass together through the press nip, such a smooth impermeable belt obtains a film of liquid on its smooth web transport surface and, thus, the press nip. In the latter part, it is generally known that when the press felt and the impermeable belt move away from each other, the paper web adheres to the impermeable belt instead of sticking to the press felt which does not have a smooth surface. is there. This situation is also utilized in US Pat. No. 4,483,745. However, since both the impervious belt and the drying cylinder of the paper machine according to US Pat. No. 5,393,384 have smooth surfaces and are intended for contact with the paper web, the paper web However, there is a considerable risk that after passing through the nip in the drying cylinder, instead of being transferred to the smooth surface of the drying cylinder as desired, it will continue to stick to the smooth surface of the impermeable belt. To do. Providing a large amount of adhesive on the surface of the enclosure of the drying cylinder probably does not ensure that the paper web sticks to the drying cylinder. US Patent No. 5,
No. 393,384 makes no mention of texturing the paper web before the drying cylinder.

German patent DE-195 48 747
Disclosed is a paper machine for making creped tissue paper, which comprises a press with a shoe press roll, a counter roll, and a suction roll, wherein the counter roll forms a first press nip with the suction roll. Second with shoe press roll
Forming an extended press nip. The felt passes through two press nips with the paper web, and then transports the paper web with itself to the Yankee dryer, which, once transferred to the Yankee dryer, the felt and the paper. The web goes around a transfer roll forming a non-compressing nip with the Yankee dryer. The suction zone is provided before and after the first press nip, and the suction zone at the front stage of this press nip is located inside the suction roll, but the suction zone at the rear stage of the press nip has a side loop shape, At this point, the felt flows alone and joins the paper web again at the entrance to the second press nip. One drawback with such a paper machine is that the paper web, before reaching the Yankee dryer,
To be remoistened by a moist felt. The paper machine does not have an impermeable belt, and the patent specification makes no mention of texturing the paper web.

US Pat. No. 5,298,124 is intended to remove the open draw of the paper web and to allow the paper web to be easily released and transferred to the fabric or belt. , A compressible transmission belt for use in a paper or board machine. The transmission belt comprises a plurality of drying cylinders via a press section with one or more press nips, and a belt that loops around a transmission roll forming a nip with the transmission belt. Transport the paper web to the drying section. For each press,
Felt is provided that passes through the press nip and encloses the paper web between the press nip and the transmission belt. Impermeable transmission belts also improve the release characteristics of the belt by breaking the liquid film formed in the press nip between the transmission belt and the paper web when the pressure on the transmission belt is cut off after the press nip. However, it is also designed so that the paper web can be more easily transferred to a loop-flowing fabric or another belt. There is no suggestion or suggestion in the patent specification that the transmission belt should be able to convey the paper web to the drying cylinder of the tissue paper machine. Further, there is no mention of texture-processing the paper web.

US Pat. No. 5,298,124 provides an excellent description of the work that a transmission belt cooperating with a press felt should perform in a satisfactory manner, and US Pat. No. 4,483,745. , 4,976,821
No. 4,500,588, No. 5,002,638
No. 4,529,643 and CA-A-1,
It also provides a description of the characteristics and design of such transmission belts disclosed in the 188,556 patent specifications. According to US Pat. No. 5,298,124, for a transmission belt intended to work with a press felt, the important work is: a) removing the paper web from the press felt without causing problems of instability. B) in cooperation with the press felt in one or more press nips,
Ensuring optimum dewatering of the paper web and its high quality; and c) a fabric or belt that receives the paper web from the press in the press section of the closed draw paper web to the press (es) downstream of the press section. To the pick-up fabric in the drying section.

As mentioned above, US Pat. No. 5,298,1
A transmission belt for the press section of a paper machine as disclosed in No. 24 has a web contacting surface that is substantially impermeable to water and air and is pressure sensitive microscale. It has a fine structure. Under the influence of the pressure of the press nip in the press section, the transmission belt is compressed so that the microscale roughness of said surface is reduced, while at the same time the surface becomes even smoother and above it. To allow a thin continuous film of water to form.

A paper machine for producing a large amount of soft paper is
It is known from several patent specifications. It is common to use stamping fabrics or felts that pass through the press nip along with the formed paper web, where the press nip presses the paper web into the stamping fabric and thus the texture pattern on one side. To get Paper machines having such textured fabrics and press nips are disclosed in US Pat. Nos. 3,301,746 and 3,53.
7,954, 4,309,246, 4,53
No. 3,437, No. 5,569,358, No. 5,59
No. 1,305 and WO 91/16493. A drawback with the paper machines disclosed in the above-referenced publications is that the dewatering in the press nip is relatively poor and therefore when the paper web is transferred to the drying cylinder the dry solids content of the paper web is low.
Therefore, the production rate of this paper machine is relatively low.

US Pat. No. 4,849,054 discloses a machine for mass producing stamped fabric webs without the use of press nips. Rolls, such as transmission rolls or felt transport rolls, form a nip with marking fabric at the transmission point of the web, where the nip surrounds a suction tube with a slit opening facing the transmission point. The stamping fabric is passed through. The nip is wide enough that the web is not squeezed as it passes. The effect of sucking from the suction tube through the narrow slit opening is sufficient not only to transfer the web to the marking belt, but also to ensure that the web is shaped according to the surface of the marking belt facing the web. However, in this case, the belt has a three-dimensional pattern. Before this transmission point, the speed of the material web is higher than that of the marking material.
The rolls that carry the web to the uncompressed nip have a smooth surface, and in practice the transfer of the dough web from the smooth surface to the dough is accompanied by considerable problems, the dough web being 30% to 50%. It is generally known to have been prepressed to a dry solids content of%.

US Pat. No. 5,411,636 discloses a soft paper in which a paper web is formed on a forming fabric, prepressed in a double-felt press nip and transferred to a coarse mesh fabric. Discloses manufacturing. When the paper web is conveyed by a coarse mesh fabric, it is exposed to a vacuum in the suction zone, as a result of which the paper web is sucked into the openings and the depressions in the fabric, thereby increasing its thickness and thus its bulkiness. Become. The coarse mesh dough then conveys the paper web to a drying cylinder. The double felt press nip has a dry solids content of the paper web of, for example, 25% to 30%.
And ensure that it will be relatively low. Since the dewatering process cannot be carried out in the nip in the drying cylinder, the dry solids content of the paper web on transfer to the drying cylinder is correspondingly low. In addition, transferring the paper web from the felt to the coarse mesh fabric is
Extremely difficult.

[0011]

SUMMARY OF THE INVENTION Accordingly, an improved paper machine for producing textured soft paper and a method of making the same enable mass production of textured fibrous webs and high drying in the preceding stage of the drying cylinder. The solids content makes it possible to achieve high production rates at reasonable costs. Further, while the textured fibrous web is conveyed to the drying cylinder by a water impermeable textured belt, it is desirable to reliably transfer the fibrous web to the drying cylinder.

[0012]

SUMMARY OF THE INVENTION A paper machine according to the present invention comprises a) a substantially water impermeable belt, a backing layer, and
At the same time as having a number of uniformly distributed recesses, the surface portion is located between each recess so that the fibrous web forms a uniform relief pattern on the web during its passage through the press nip. A textured belt including a textured web contact layer; and b) a substantially water impermeable textured belt from a press for transporting the textured fibrous web to a transmission nip. Be configured to run to a drying cylinder; c) the press felt has a water film formed in the press nip immediately after the press nip and on a substantially impermeable textured belt. It is configured to run away from the impermeable textured belt at one point in the preceding stage of breakage, and d) the device for applying the adhesive is in front of the transmission nip. It is disposed, on the inclusion body surface of the drying cylinder, and / or, in the textured reduction processed on filamentous webs, to impart pressure-sensitive adhesive layer which is continuous, characterized.

The method according to the invention comprises: a) having a carrier and a large number of uniformly distributed recesses,
A textured belt having a surface portion disposed between each recess and including a web contact layer that forms a uniform pattern on the fibrous web during passage of the fibrous web through the press nip. Creating a texture in a fibrous web with a substantially impermeable belt,
b) running a substantially impermeable textured belt from the press to the drying cylinder to convey the textured fibrous web to the transmission nip; c) immediately after the press nip, and Running the press felt away from the water impermeable textured belt at a point in the preceding stage where the water film formed in the press nip on the substantially water impermeable textured belt breaks And d) Continuation of the adhesive on the surface of the enclosure of the drying cylinder and / or on the textured fibrous web, with the aid of a device for applying the adhesive at a point before the transmission nip. It is characterized in that a layer for applying is provided.

[0014]

According to the invention, when a water-impermeable textured belt is also used to transfer the pressed paper web to the transmission nip in a Yankee dryer in the drying section of a paper machine. It has been surprisingly found that in a textured belt included in a paper machine according to the present invention, water impermeability or substantial water impermeability is an extremely desirable property. This property makes it possible to pressurize the steam formed by the water present in the depressions or depressions in the depressions or depressions in the textured pattern as a result of heating the Yankee dryer, and thus in the press section. As a result of the pressing effect, the paper fibers present in the depressions or depressions are also pressed, and the paper fibers in the Yankee dryer nip are the parts of the paper fiber web that are present between the ridges of the textured pattern and the Yankee dryer. As soon as it becomes thinner, it is pressed into the depression or recess. The desired textured effect and large amount of paper web are thus achieved.

The layer of textured or textured belt intended for contact with the paper web is provided with the property of reversible compressibility so that the textured belt is compressed in the transmission nip in a Yankee dryer. In some cases, the textured effect and the productivity can be improved. Then the textured belt leaves the transmission nip,
Resuming its uncompressed state creates a vacuum, which is
Contributes to the formation of steam which, in turn, facilitates separation of the textured belt and the paper web after the transmission nip as well as faster drying of the paper web on the Yankee dryer, i.e. higher paper. Promote production capacity. The faster the belt recovers from the uncompressed state, that is, the higher the reversible compressive recovery force, the better the vacuum forming effect.

The textured effect of the textured belt included in the paper machine according to the present invention has, of course, been selected taking into account the desired texture pattern of the paper produced. The texture pattern is regular in the transverse direction of the textured belt, or if the texture pattern of the paper web is intended to include extra prominent additional patterns such as pictures, logotypes,
The texture pattern has a regular basic pattern of depressions or depressions and ridges, on which an additional pattern is superimposed. "Regular" does not necessarily mean that the pattern appears regular in all directions of the textured belt. For example, if the paper is a soft paper that will be creped,
The tighter dominant transverse pattern (transverse to the machine direction) improves the creping effect compared to the ridge and dimple longitudinal pattern. Therefore, this pattern can be used to modify the properties of the paper in the desired direction.

Considering the material of the textured belt or its surface layer which is intended to come into contact with the paper web, the textured pattern may be an etching, calendering, laser treatment, or embossing, etc. It can be achieved in any known manner.

The density of the textured pattern can also be used to affect the effectiveness of the paper web drying process on a Yankee dryer. Therefore, as a result of the fewer contact points between the Yankee dryer and the paper web, the drying effect derived from the Yankee dryer is reduced, but the more fluffy parts of the paper web located between the thinner contact points. The drying effect derived from the hot air hood around the Yankee dryer is improved.

The invention is described in more detail below with reference to the accompanying drawings.

[0020]

The invention will now be more fully described below with reference to the accompanying drawings, which illustrate preferred embodiments of the invention. However, the present invention can be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, but rather to these embodiments, the disclosure of which is thorough. It is presented so as to be both complete and complete and to fully convey the scope of the invention to those skilled in the art. Like reference numerals refer to like elements throughout.

1 to 3 schematically illustrate parts of a paper machine for producing a textured web 1 of soft paper such as tissues and other low density paper products. Each of the paper machines has a wet section 2, a press section 3,
And a drying section 4.

The wet section 2 comprises a head box 7,
It includes a forming roll 8, an endless conveying inner closing 9, and an endless coated outer closing 10 composed of a forming fabric. The inner closing 9 and the outer closing 10 each form its own loop and flows around a plurality of guide rolls 11 and 12, respectively.

The drying section 4 comprises a drying cylinder 5 covered with a hood 30. A Yankee dryer is suitable as the drying cylinder. On the outlet side of the drying section, a creping doctor is configured to crepe the fibrous web 1 leaving the Yankee dryer. Supply device 31
Is also provided in order to apply a suitable adhesive to the surface of the enclosure of the Yankee dryer 5 immediately before the transmission nip.

The press section 3 comprises a shoe press with a shoe press roll 14 and a counter roll 19, which rolls 14 and 19 form an extended press nip with respect to each other. The press section also flows in a loop around the guide roll 6,
It also has an endless press felt 15 and a substantially water impermeable endless belt 16, which according to the invention is a textured belt. The substantially impermeable textured belt 16 includes a counter roll 19, a transmission roll 17,
And, it flows in a loop around the plurality of guide rolls 18. The transmission roll 17, together with the Yankee dryer 5, has a low linear load, that is, 30 kN (kilonewton).
To a 60 kN transmission nip, and thus the substantially water impermeable textured belt 16 passes through this transmission nip.

In the embodiment illustrated in FIGS. 1 and 2, the press section 3 also includes a roll press, which comprises a suction press roll 13 and the counter roll 19 described above to form a press nip, and substantially A water-impermeable textured belt 16 and press felt 15 pass through the press nip together with the fibrous web 1. Later in this initial press nip, the press felt 15 laterally surrounds the suction press roll 13 and the two guide rolls 32 away from the fibrous web 1 and the substantially water impermeable textured belt 16. Guided in a loop. The press felt 15 rejoins the fibrous web and the substantially impermeable textured belt 16 just prior to the extended press nip. If desired, suction devices may be configured in the side loops of the press felt 15 to increase the capacity of the press felt to absorb water at the entrance to the extended press nip.

In the embodiment illustrated in FIGS. 1 and 3, the inner closure 9 of the wet section 2 is also used as the press felt 15 in the press section 3.
Is a felt that is guided to and thus flows back into the forming roll 8 in a loop.

In the embodiment illustrated in FIG. 2, the inner closing 9 of the wet section 2 is a molding fabric, the press felt running around a pickup loop 20 constructed in close proximity to the loop of the fabric 9, The press felt 15 and the dough 9 flow in contact with each other and transfer the fibrous web from the dough 9 to the press felt 15. The pickup roll 20 may be provided with a suction shoe (not shown). As an alternative, the pickup roll with suction shoe may be replaced with a pickup suction box.

FIG. 4 schematically illustrates parts of a paper machine according to another embodiment of the present invention. This is similar to the one illustrated in Figure 1, except that the press felt 15 has two
It is not guided in a side loop between the two press nips, but instead involves a counter roll 19, so that the fibrous web 1 has a substantially impermeable textured belt 16 and press felt 15. The exception is that it is held in a sealed state during. This embodiment may be employed when the fibrous web has little risk of rewetting.

FIG. 5 schematically illustrates parts of a paper machine according to another embodiment of the present invention for making textured webs of soft paper such as tissues and other sanitary paper products. To do. The paper machine has a wet section 2,
A press section 3 and a drying section 4 are provided. The wet section 2 comprises a headbox 7, a forming roll 8, an endless conveying inner closing 9 and an endless coated outer closing 10 constituted by a forming fabric. The inner closing 9 and the outer closing 10 run in a separate loop around each of the plurality of guide rolls 11 and 12. The drying section 4 comprises a drying cylinder 5 covered with a hood 30. The drying cylinder is preferably a Yankee dryer. A creping doctor 21 is provided on the outlet side of the drying section to crepe the fibrous web leaving the Yankee dryer 5. The applicator 31 is also provided to apply a suitable adhesive onto the surface of the enclosure of the Yankee dryer 5 immediately before the transmission nip. The press section 3 comprises a shoe press with a shoe press roll 14 and a counter roll 19, said rolls 14 and 19 forming an extended press nip with each other. The press section also has an endless felt 15 that loops around the guide roll 6 and a substantially water impermeable belt 16, which is a textured belt according to the present invention. A substantially water impermeable textured belt 16 runs in a loop around a counter roll 19, a transmission roll 17, and a plurality of guide rolls 18. The transfer roll 17 forms a low linear load transfer nip with the Yankee dryer 5 and thus the substantially impermeable textured belt 16 passes through the transfer nip. In this embodiment, the substantially water impermeable textured belt 16 is also used as the inner closing 9 in the wet section 2, the loop of which extends to the forming roll 8. Thus, the substantially water impermeable textured belt 16 comprises a transfer roll 17, guide rolls 18 and 1 between the wet section 2 and the dry section.
1, and runs in a loop around the forming roll 8.
The substantially water-impermeable textured belt conveys the fibrous web at its lower surface from the forming roll to the drying cylinder.

In the embodiment illustrated in FIGS. 1-5, the counter roll 19 is a smooth roll and is constructed within a loop of a substantially water impermeable textured belt 16. In an alternative embodiment (not shown) of the press section according to FIGS. 3 and 5, rolls 14 and 19
Each position of is opposite, i.e. shoe press roll 14
Is constructed within a loop of a substantially water-impermeable textured belt 16 and the counter roll is made of press felt 15
Is located within the loop. In such a configuration, the counter roll can be a suction roll, a grooved roll, or a blind drilling roll.

The substantially water impermeable textured belt used in the above-described embodiment of the paper machine according to the present invention comprises:
It comprises a backing layer 33 and a web contact layer 34 having a number of uniformly distributed recesses 35, with flat or arcuate surface portions 36 disposed between each recess. ,
Please refer to FIG. 6 to FIG. According to a first embodiment, as illustrated in FIG. 6, a substantially water impermeable textured belt 16 comprises a tight layer 33 forming the backing layer and a web contact layer as described above. The fabric forming 34 is a component. The fabric 34 is coated with a polymer to enclose the yarns of the fabric without altering the structure of the fibers, which is formed from recesses and arcuate or convex surface portions 36 located between each recess. ing. The recess 35 and the surface portion 36 are in turn formed by a machine thread (as indicated by the arrow) and a thread of fabric extending transversely to this direction. The recess 35 is closed by a tight backing layer 33 formed by the coating polymer on the surface of the fabric that is not in contact with the web. The aforementioned arcuate surface portion 36 is provided with both a long arc-shaped ridge 36a of the fabric thread running in the longitudinal direction and a knuckle 36b of the thread running in the transverse direction. Creates small bowl-shaped depressions in the web. In the embodiment illustrated in Figure 6, the substantially water impermeable textured belt has 100 knuckles 36b per square centimeter. Generally, it may have 25 to 150 knuckles per square cm, but preferably has 50 to 100 knuckles per square cm. Recesses, ridges, and
This construction of the knuckle produces a texture pattern corresponding to the fibrous web as it passes through the extended press nip with the textured belt 16 and the press felt 15. The polymer coating on the fabric ensures that the fibrous web adheres to the substantially water impermeable textured belt as it flows from the expanding press nip. This ensures that the fibrous web is entrained by the substantially water impermeable textured belt 16 but not the press felt 15. The structure of the web contact layer of the water impermeable textured belt, ie, the polymer coated fabric 34, when combined with the surface of the enclosure of the drying cylinder 5, coated with a continuous adhesive layer, allows the fibrous web to pass through the transmission nip. It is also ensured that when it goes out, it is safely transferred to the drying cylinder 5.

What is commonly referred to as a coarse single layer fabric has 100 knuckles per square centimeter and is used in the first embodiment of the substantially water impermeable textured belt described above. obtain. The backing layer is substantially impermeable to water, but is composed of a suitable polymeric resin material, such as each of the polymers described below for the polymeric layer in the second embodiment of the substantially water impermeable textured belt. May be included. The polymer for coating the textile yarn can be selected in the same way.

According to a second embodiment, the substantially water impermeable textured belt 16 has a carrier 33 forming the backing layer 33 described above and a hardness of 50 Shore A to 97 Shore A. , The polymer layer 34 on the web contact side is included as a component, and the polymer coating is a part of ISO 4287.
R2 = 2 μm to 80 μm when measured according to I
Has a degree of roughness in the uncompressed state of, and
When a linear load of 20 kN / m to 200 kN / m is applied on a substantially impermeable textured belt, R2
= 0 μm to a lower degree of roughness of 20 μm, and when the pressure exerted on the substantially impermeable textured belt ceases, its ability to return to its uncompressed degree of roughness. I have it. The R2 = value is more particularly a height of 10 points, which is 5 peaks and 5 at the reference length measured from a line parallel to the center line but not crossing the surface profile. The average distance between the two deepest points is specified in the above ISO standard. Substantially impermeable textured belts are available from the American Society of Testing and Mate.
It is preferred that air permeability lower than 6 m ³ / m ² / min is measured according to the standard test method for air permeability of textile fibers of rials), ie according to the procedure described in ASTM D 737-75. .

Substantially water impermeable texture belt 16
Are therefore compressible under the influence of the prevailing pressure in the expansion press nip. Therefore, the substantially water impermeable textured belt 16 exhibits an uncompressed state upstream and downstream of the expansion press nip, and the surface, i.e., the web transport surface facing the fibrous web, is substantially The water-impermeable textured belt has a high degree of roughness in the uncompressed state and the substantially water-impermeable textured belt has a lower degree of roughness in the compressed state. ,
As a result, when the substantially impermeable textured belt passes through the expanded press nip with the press felt 15 and the fibrous web 1, the substantially impermeable webbed web in the compressed state. The transport surface has sufficient smoothness to form a continuous liquid film on the web transport surface and is substantially non-permeable after the substantially water-impermeable textured belt has expanded in the thickness direction. The non-compressed web transport surface of the very water impermeable textured belt has sufficient roughness to allow breakage of the continuous liquid film.

In order to occupy a large percentage of the web contact surface, ie occupy 20% to 50%, the compressible polymer layer 34 is provided with a number of the uniformly distributed recesses 35 mentioned above. There is. These recesses can be formed in a number of ways to achieve the desired effect of textured relief patterns in the fibrous web to increase its bulk. The recess may consist of continuous grooves in the polymer layer 33, see FIG. 7, but each groove extends in the machine direction. According to another embodiment, the groove extends obliquely from one edge to another and forms an angle of 10 ° to 80 ° with the machine direction. According to another embodiment, see FIG. 8, the recess is
From 10 °, forming diagonally intersecting grooves extending in a group from the first edge to the second edge and a second group from the second edge to the first edge And intersecting grooves forming an angle α of up to 170 °. Each groove in various embodiments may be straight, as shown, or may be corrugated, such as sinusoidal or zigzag. The distance a between the two grooves 35 running in the same direction is 1 m
It can be in the range of m to 3 mm. The width b of the groove is
Within the range of 0.5 mm to 1.0 mm, the depth c
Is in the range of 0.1 mm to 1.0 mm.

According to another embodiment (not shown), the recesses consist of hollow holes of identical or similar shape. These hollow holes may be circular, elliptical or polygonal in shape, for example triangular, square or hexagonal, but with a maximum dimension in the interval 0.5 mm to 3.0 mm, The depth lies in the interval 0.5 mm to 1.0 mm.

All or some of the recesses, whether individually or in groups, are regular within the length unit of the belt, eg, number, letter, commercial representation, or corporate representation. It can be constructed with special symbol shaped hollow holes that repeat at intervals.

A substantially water impermeable textured belt, according to the second embodiment described above, follows the process described in US Pat. No. 5,298,124 discussed in the introductory part.
It can be constructed. The polymer coating 34 comprises a polymer composition such as acrylic polymer resin, polyurethane polymer resin, and polyurethane / polycarbonate resin. The polymeric coating also contains particles of filler, which have a different hardness than the polymeric material, and which include kaolin, clay, polymeric material,
Alternatively, stainless steel is preferred but metal may be a constituent. Carriers that make up the backing layer 33 include any type of base element that can be endless in some way. The scope of this term also includes seamed base elements. The carrier may be composed of a single-layer or multi-layer fabric made from, for example, monofilaments such as polyester, polyamide. The base element is made of adhesive, mixed filament winding, polymer foil / polymer film, warp knitting, etc.
It can also consist of fiber webs (non-woven) held together. The carrier can be coated on the back side with the same type of polymeric material used for the polymer layer 34.

Transmission as described in US Pat. No. 5,298,124, intended for pressing in the press section and usable for transferring a paper web from the press section to a dry substrate. It is surprising that the belt can be used to great advantage for textured soft paper and transferring it directly from the shoe press nip to a Yankee dryer or some other drying cylinder. That is. As is well known, the conditions in a Yankee dryer are quite different from those in a conventional press nip. When a Yankee dryer is used, soft paper is not pressed for direct dehydration. Rather, there is a problem in supporting the soft paper web to the surface of the Yankee dryer enclosure, so that the fabric of the soft paper web effectively sticks to the surface of the Yankee dryer, thereby causing it to stick to the paper web. Has achieved good heat transfer. This is exactly the effect achieved with the transmission belt included in one embodiment of the paper machine according to the invention, but with a satisfactory hindrance of sticking after the last press nip in the press section. Because of the re-moistened paper, D
This effect cannot be achieved with a press felt as described in E-195 48 747. For the reasons mentioned above, this effect is not achievable or only achievable to a slight extent when utilizing transmission belts such as those described in US Pat. No. 5,393,384. The compressibility of the transmission belt used in the paper machine according to the invention results in a lower specific pressure at the sticking point, which in turn provides an improved actuation rate, i.e. a higher production rate. . This property also
This results in increased evaporation of water exiting the soft paper web, i.e. causing a faster drying of the soft paper web in a Yankee dryer, which also contributes to higher production rates.

The paper machine according to the invention has a press nip of the single felt type, but with a high dry solids content in the preceding stage of the drying section, ie up to 55% content of the textured fibrous web. Which is to be compared with the dry solids content of up to 45% achieved with paper machines in service today. This improvement can be used either for running the paper machine at higher production rates or for reducing energy consumption in the drying section. It is then also possible to reduce the diameter of the drying cylinder.

Utilizing each of the illustrated and described embodiments, if desired, a guide roll is constructed in the loop of the substantially water impermeable textured belt 16 immediately preceding the transfer roll 17. May be.

When the embodiments shown and described are used, the transmission member is used by being constituted by the transmission roll 17. According to an alternative embodiment (not shown), the transmission roll is replaced by the substantially water-impermeable textured belt itself, whereby the sector angle is in the range of, for example, 30 ° to 60 °. It is then possible to flow around a predetermined part of the drying cylinder and together with the drying cylinder form an extended transmission nip.

Although all of the paper machine embodiments described above have a press section with a shoe press, the present invention is also applicable where the press section lacks a shoe press, Alternatively, the press roll having at least one press with two press rolls around which the press felt flows is a suction roll, a grooved roll or a blind drilling roll.

Many modifications and other embodiments of this invention will occur to those skilled in the art to which this invention pertains, thanks to the teachings set forth in the foregoing description and associated drawings. Therefore, it is to be understood that this invention should not be limited to the particular embodiments disclosed, as multiple modifications and other implementations are intended to be included within the scope of the appended claims. Is. Although specific terms have been employed herein, they have been used in a generic and descriptive sense only and not for purposes of limitation.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a paper machine according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a paper machine according to a second embodiment of the present invention.

FIG. 3 is a diagram illustrating a paper machine according to a third embodiment of the present invention.

FIG. 4 is a diagram illustrating a paper machine according to a fourth embodiment of the present invention.

FIG. 5 is a diagram illustrating a paper machine according to a fifth embodiment of the present invention.

FIG. 6 shows a portion of a substantially water impermeable textured belt composed of a backing layer in the form of a tight polymer layer and a web contact layer in the form of a polymer coated fabric. FIG.

FIG. 7 consists of a backing layer in the form of a carrier and a carrier-supporting web contact layer in the form of an elastic compressible polymer layer, the polymer layer being provided with longitudinal grooves. FIG. 3 is a partial top view of a textured belt that is water impermeable.

8 is a cross-sectional view of the textured belt according to FIG. 7.

FIG. 9 is a partial top view of a substantially water impermeable textured belt of the same type as the textured belt according to FIG. 7, but with diagonally intersecting grooves. Is.

─────────────────────────────────────────────────── ─── Continuation of the front page (31) Priority claim number 09 / 211,647 (32) Priority date December 15, 1998 (December 15, 1998) (33) Priority claim country United States (US) ( 31) Priority claim number 09 / 212,798 (32) Priority date December 16, 1998 (December 16, 1998) (33) Priority claiming country United States (US) (72) Inventor Ampulse Key Robert S United States of America Ohio 45014 Fairfield Red Oak Drive 5674 (72) Inventor Ostenddorf Ward United States Ohio 45069 West Chester Oregon Pass 6331 (72) Inventor Porat Osman United States Ohio 45249 Montgomery Tiburon Drive 8741 (56) References Flat 6-158578 (J , A) JP flat 6-57678 (JP, A) JP Akira 59-64455 (JP, A) JP-T flat 11-514052 (JP, A) (58 ) investigated the field (Int.Cl. ^7, DB Name) D21F 1/00-13/12 D21H 27/00-27/42

Claims (4)

(57) [Claims] 1. A paper machine for texturing a wet fibrous paper web and for drying it, the paper machine pressing the fibrous web with two cooperating pressing members. A press having a press nip formed between press members for removing water from the web, a heating type drying cylinder downstream of the press, wherein a part of the surface of the cylinder A cylinder intended to further dry the fibrous web by receiving a fibrous web pressed around it, thereby evaporating at least part of the water remaining in the web, and A water-impermeable, textured belt having a web-contacting surface defining a number of regularly distributed recesses and a surface portion disposed between each recess. Addition of texture The belt is configured to pass through the press with the fibrous web such that the recesses in the web contacting surface initially provide a uniform textured pattern with thicker and thinner portions of the fibrous web. The impermeable, textured belt formed into a web is then further configured to convey the fibrous web to the heated drying cylinder such that the surface portion of the belt is the web. A paper machine having a water impermeable textured belt adapted to abut the thinner portion of the web against the surface of the cylinder such that water in the thicker portion of the web is vaporized. 2. A paper machine belt for wetting a wet fibrous paper web, drying it, and advancing the web between a press and a drying cylinder, the belt comprising: A water impermeable textured belt having a web contacting surface defining a number of regularly distributed recesses and a surface portion located between each recess; A textured belt is passed through the press with the fibrous web such that the recesses in the web contacting surface initially have an even textured portion having thicker and thinner portions. Forming a processing pattern on the fibrous web, the impermeable textured belt is then further conveyed the fibrous web to the heating drying cylinder, the surface portion of the belt, The paper machine belt, wherein the thinner portion of the web is abutted against the surface of the cylinder to vaporize water in the thicker portion of the web. 3. A method for applying a texture to a wet fibrous paper web and drying the wet fibrous paper web, which comprises advancing a press through the wet fibrous web, and
Squeezing the fibrous web to remove water from the web, advancing the fibrous web to a heated drying cylinder, extending the fibrous web around a portion of the heated drying cylinder And further drying the fibrous web by evaporating at least a portion of the water remaining on the web, extending through the press to the surface of the drying cylinder, a water impermeable Transporting the fibrous web between the press and the drying cylinder using a textured belt, abutting the fibrous web against the drying cylinder, and a number of regularly distributed Utilizing the web-contacting surface of the water-impermeable textured belt that defines the recesses that have been created, including subjecting the fibrous web to textured processing. To the process, while the belt and the fibrous web is advanced through the press, it occurs when the fibrous web abuts against the drying cylinder,
The method wherein the recesses are configured to form a textured pattern on the fibrous web. 4. The impermeable textured belt also conveys the fibrous web from a headbox for forming the web to the press.
The method as described in 1 ..