JP2008545068A - Method for producing paper web, especially gravure paper - Google Patents

Abstract

The present invention relates to a method for producing a paper web or other fibrous web. By this method, the fibrous web is subjected to pressure in the press section at the penultimate press nip and then at the final press nip. One side of the fibrous web contacts the smooth surface as it passes through the penultimate press nip, and the other side of the fibrous web contacts the smooth surface as it passes through the final press nip.

Description

  The present invention relates to a method for producing paper or other fibrous web according to the preceding paragraph of claim 1.

  At present, the following structure is embodied as a high-speed paper machine for producing high-quality SC paper (SC-super-calendar). That is, what is known as a roll blade former, or wire former, is a conventional press section having a forming roll and a dewatering foil, without a flexible foil, and having three press nips arranged downstream. It is configured in combination with. The press nip can also be formed with a shoe press roll. Following these, there is preferably an independent press unit for the fourth press nip. Outside the paper machine, the fiber web is force-rendered by at least two off-line multi-nip calenders that allow the paper machine production to follow lower super calender speeds.

  In order to set the required inlet moisture and the most even moisture distribution possible across the entire width of the web, the fiber web is usually dried in the drying section until the residual moisture is reduced from 2 to 3% and the winding station Before entering, when still in the paper machine, it is moistened using a water application unit, for example a nozzle-type wetting device. The residence time of the spool around which the paper web is wound is 0.5 to 2 hours until the paper web is supercalendered in the calendar device after winding in the paper machine. By being dried and having a long residence time, it can be assumed that there is a very good moisture distribution in every direction in the paper web.

  Integrating a multi-nip calender into a paper machine (online process) will generally significantly increase the speed of the supercalendering process. Due to the short residence time in the nip and other web running conditions, the online process is cost-effective compared to the conventional offline process described above. However, at the same time, in particular in the form of a mottling and a large number of missing dots, leads to quality disadvantages that represent printability in the rotogravure printing process.

  This type of online process is implemented in the following manner. That is, a roll blade former with or without a flexible foil in a twin wire region, with two independent shoe presses or one independent shoe press and a subsequent shoe press connected to a multi-nip calender used.

  Alternatively, a roll blade former with or without flexible foil in the twin wire region and a conventional 3-nip press with or without shoe nip in conjunction with a multi-nip calender are used.

  Alternatively, a roll blade former without a flexible foil in the twin wire region and a normal 3 nip press with or without a shoe nip and an independent fourth press in conjunction with a multi-nip calender are used.

  Compared to an offline process, the online process can be made much more productive due to unwinding losses as a result of the omission, unwinding and unwinding of the paper web following calendering.

  A conventional press section configured as a three-nip press and without an additional independent fourth press typically exhibits a very high degree of paper structural duplex due to the asymmetric dewatering state in the press, This is because, in the second and third press nips, dewatering is performed only upward. When the shoe nip is actuated in the third position, the dryness can be increased considerably, but this generally increases the speed and therefore also the productivity, and the double-sided nature of the paper is more strongly dewatered towards the top This further increases.

  A press arrangement with two independent press nips is felt in a quadruple shape or has an impermeable transport belt at the second low position. This allows the web supported with low web tension to run. In the case of a quadruple felt configuration, this increases the roughness of the machined paper. For arrangements with a transport belt in the second low position, the machined paper exhibits increased duplex.

  The object of the present invention is that of fiber webs, in particular high quality SC paper, with improved results in terms of feasibility, ie run time and material efficiency, and product quality, paper roughness, printability (defect dots). It is to provide a manufacturing method.

  According to the invention, this object is achieved by a method of producing paper or other fiber web in which the fiber web is pressed, in which the fiber web is subjected to pressure in the press section at a plurality of press nips. One side of the fiber web is guided through the second to the second press nip of the press section with a smooth surface in contact, and the opposite side of this one side of the fiber web passes the smooth surface through the last press nip of the press section. Guided in contact.

  Thus, according to the present invention, the fiber web is calendered on both sides with low dryness in the last two press nips of the press section so that each side of the fiber web contacts the smooth side through the press nip. This is because they are guided. Therefore, double-sided macrocalendering of the surface of the fiber web is performed in the last two press nips, which significantly improves the ability to be calendered in subsequent calendering devices.

  In our experiments in this regard, due to the double-sided wet calendering according to the invention in the press section, the supercalendering line force required for the special PPS roughness following supercalendering is less than 100 KN / m Can be up to.

  As a result, the quality of the final product is significantly improved because the negative effects of supercalendering, such as roll burn or reduced bulk due to supercalendering, can be significantly reduced by reducing the supercalendering line force. .

  The smooth surface with which the fibrous web contacts as it passes through the press nip can be formed by either a roll shell with a smooth cover or a smooth conveyor belt.

  If the fibrous web is brought into contact with the press nip with a conveyor belt, it can be permeable or impermeable depending on the application.

  A preferred improvement of the invention comprises a 3 nip press with a central roll and an independent press with a single nip, the third nip of the 3 nip press being the second press after the press section, One nip provides a press section that is the last press of the press section.

  Another embodiment of the present invention provides a fibrous web that is guided with a conveyor belt through second and third press nips formed between a central roll and a press roll of a three nip press.

  In another refinement of the invention, one side of the fiber web guided through the penultimate press nip is brought into contact with the conveyor belt and the other side of the fiber web guided through the penultimate press nip is Contacted with press felt. Thus, dewatering is performed in the direction of the press felt, while the fibrous web is smoothed by contacting the smooth conveying belt in a wet state.

  As mentioned above, for example, if the pressing device is formed with a 3 nip press with a central roll and a downstream independent press with a single nip, one side of the fiber web is of 3 nip press It is preferably guided through the third press nip in contact with the peripheral surface of the central roll, and the other side of the fiber web is guided in contact with the press felt through the third press nip of the three nip press. The press nip forms the second press nip from the end of the press.

  Furthermore, one side of the fibrous web is preferably guided through the last press nip in contact with the press felt, and the other side of the fibrous web is brought into contact with the peripheral surface of the press roll and the last press nip. This last press nip can be formed by a single press nip of an independent press.

  In order to be able to reach higher production speeds, it is necessary to increase the dryness after the press section, for example to prevent the fiber web from overstretching and breaking due to web tension. By forming the penultimate press nip and / or the final press nip as a shoe press nip, the dryness of the fiber web can be increased. For example, using a shoe press for the penultimate press increases the dryness by 4%. Furthermore, the longer the residence time of the fiber web in the shoe press nip, the greater the calendering effect compared to a conventional press nip.

  When the fiber web is guided, for example, on a conveyor belt via a three nip press and through a single press nip of an independent press, the fiber web is conveyed from the conveyor belt to the press felt by a conveying suction roll. On top of this, it is preferred that the above-mentioned fiber web is inserted through a single press nip of an independent press.

  In the method of the present invention, when calendering is performed in the online process of the fiber web, for example in the subsequent process (online calendering), this requires very high requirements for the mass per unit area and the widthwise characteristics of moisture, This is for supercalendering, which is extremely high compared to the conventional offline process. One preferred embodiment of the method according to the invention is to dampen at least once in the width direction, preferably after the press section, when the moisture content is less than 50%, in order to modify the width direction moisture properties of the fiber web. An agent is selectively applied to the fibrous web.

  Furthermore, it is preferable to selectively apply a damping agent to the fibrous web at least once in the width direction in the forming section and / or the press section in order to modify the width direction moisture characteristics.

  The fibrous web is preferably formed of a vertical gap former, in particular a twin wire former.

  In these cases, the gap former has a flexible formation foil. This improves formation and half-tone and full-tone mottling. Experimental results show that the use of a flexible formation foil results in a dehydration range between 2% and 8% dryness, preferably between 3% and 6% dryness and significantly reduces the formation index by Ambertec can do.

  As a result of the experiment, the formation of 20% on average was improved and the mottling of 10% was improved. Compared to a formation without a formation foil, in the case of a formation with a flexible formation foil, it is possible to use a fiber material with a fairly low level of refining in order to obtain a fiber web with the same quality characteristics Is possible. As a result of the low level of grinding, the special grinding energy required is considerably reduced. The result is an energy cost gain of up to 20% in the area of fiber material preparation, assuming that the special digestive energy, digestion and formation / mottling levels are linearly related to each other. .

  For the above mentioned properties, it is clear that the best results are achieved when preferably using 1 to 10 flexible formation foils, particularly preferably 3 to 5 flexible formation foils.

  Furthermore, the formation foil is advantageously provided with two forming fabrics with a fibrous web disposed between them and is pressed into the sandwich with a preferred contact pressure in the range of 5 kPa to 30 kPa, 8 kPa to 25 kPa.

  Furthermore, the flexible formation foil acts to further dewater in the twin wire region.

  In order to perform optimal dewatering, the contact angle of the forming roll by the two forming fabrics is approximately 30 ° to 60 °, preferably 40 ° to 55 °. Thus, even at speeds up to 2000 m / min, a dryness of 18% to 20% can be achieved at the end of the forming section.

  As the speed of the fibrous web increases, the properties of the forming fabric used for dewatering and the structure of the paper surface play a more important role.

In this case, the forming fabric used ensures a sufficiently high dewatering rate, has a low moisture content, and exhibits a fine surface on the paper. Number of fiber support points having a fabric thickness of less than 0.7 mm, preferably less than 0.65 mm, more than 1400 / cm ² , preferably more than 1500 / cm ² , particularly preferably more than 1600 / cm ² Forming fabrics having are particularly suitable for this purpose.

  After the pressing section, the fibrous web runs through the drying section and is dried in this section. There are various possibilities of drying the fibrous web, for example drying on a heated cylinder or impingement drying with hot air.

  In another variant of the invention, the press section simply comprises three press nips, and the impingement drying device is additionally arranged between the press section and the actual drying section. With this arrangement, favorable results can be achieved, in particular good running properties and good rotogravure printability. In particular, the double-sided nature of the paper web can be significantly reduced by this arrangement.

  The three press nips are preferably pre-formed by a three nip press having a central roll and two press rolls. This results in a compact structure and is therefore advantageous in terms of required space and manufacturing costs.

  The first and / or third press nip in this variation can be formed as a roll press or a shoe press in any case. In the case of a shoe press, the drying performance can be increased.

  A preferred form of impact drying device or impact device is the High Dryer, which in particular comprises two drying cylinders and an impact hood. In this case, the drying cylinder is preferably slightly evacuated. It is advantageous to use a stabilizer to evacuate. In this case, the drying cylinder of the impact drying device is preferably 3 meters or more.

  Subsequent to drying of the fibrous web in the drying section, for example in the case of gravure paper, it is fed to a multi-nip calendering device, for example. In this case, the multi-nip calendering device can have a number of rolls of 6-12.

  To increase productivity, the multi-nip calendering device is preferably an online calendering device, for example because the web speed of offline calendering is much lower and the paper web needs to be rewound.

  In particular, for offset printing applications, over-drying of the fibrous web and subsequent re-humidification between the drying section and the online multi-nip calender may be advantageous, for example while trying on fiber materials with a high fines ratio. As shown, this significantly reduces or prevents defects in dimensional stability such as cockling and fluting. One preferred embodiment according to the method of the present invention, when exiting the drying section, causes the moisture content of the fibrous web to be lower than the equilibrium moisture content under standard climatic conditions. Another preferred embodiment of the method according to the invention further allows the fibrous web to be selectively humidified, preferably in the width direction, before entering the calendering device. By selectively humidifying in the width direction, fluctuations in the width direction humidification characteristics can be compensated.

  In order to form the same paper surface on both sides, an equivalent double-sided treatment of the paper web is advantageous. Thus, one preferred embodiment of the present invention is that one of the sides of the fiber web in each case contacts the heated roll in the first sequence of calendar nips and the other side of the fiber web has the other side of the calendar nip. The heating roll is contacted in the sequence of 2.

  In order to have the same smoothness on both sides, it is preferred that both sides of the fibrous web be humidified after leaving the drying section.

  In this case, each side of the fiber web that is in contact with the heated roll can be humidified before each sequence of the respective calendar nip.

  On the other hand, other embodiments humidify both sides of the fibrous web before entering the calendering device.

  In addition, other humidifiers can be provided between the positions described above to impart the required amount of moisture to the fibrous web.

  When the fibrous web is humidified to a moisture content of 7% to 9%, preferably 8%, the smoothness of the calendered fiber web can be optimized.

  In this case, it is preferred to have a moisture content of 7% to 9%, preferably 8%, before the calendar nip of each sequence.

  The fiber web is preferably humidified by a steam humidifier and / or a nozzle humidifier.

  Due to the extremely short residence time between the application of the damping agent and the first calender nip, the water droplets must be finely dispersed in order to suitably humidify the fiber web. This can be achieved with a two component nozzle humidifier of air and damping agent.

  Preferably used for the production of gravure paper or SC or SCA + paper having 25% or more filler, particularly preferably 30% or more filler, in the above-mentioned method having various embodiments according to the present invention. Can do.

  The present invention will be described in detail using two exemplary embodiments.

  FIG. 1 shows a paper machine 1 for the production of SC paper which preferably has 25% or more filler.

  During the production of the fiber web 2, the fiber web runs continuously through subsequent sections of the paper machine 1, namely the forming section 3, the press section 4, the drying section 5 and the calendering device 6, after which a winding (not shown) is taken up. It is wound on a reel by the device.

  The fibrous web 2 is formed in the material inlet gap 7 between the upper forming fabric 11 and the lower forming fabric 10 in a forming section 3 configured as a vertical gap former. After the material inlet gap 7, the sandwich consisting of the upper forming fabric 11, the fibrous web 2 and the lower forming fabric 10 has an angle of 30 ° to 60 °, preferably 40 ° to 55 °, in order to dehydrate the fibrous web 2. In range, it is wound around the forming roll 8.

  The dewatered fibrous web 2 is further dewatered by the 3 flexible formation foil 12 to a dryness range between 2% and 8%, preferably between 3% and 6%. The flexible formation foil 12 in this case is pressed against the sandwich including the upper forming fabric 11, the fiber web 2, and the lower forming fabric 10 with a contact pressure in the range of 8 kPa to 25 kPa.

  In this way, the formation and half-tone and full-tone mottling are improved. Experiments by using a flexible formation foil show that the formation index by Ambertec can be significantly reduced. In addition, an average of 20% formation and 10% improvement in mottling was observed. When molded with a flexible formation foil, a fibrous web having the same quality characteristics can be obtained using a fibrous material having a significantly lower level of digestion compared to molding without the formation foil. As a result of the lower level of digestion, the special digestion energy required is considerably reduced. The result is an energy cost gain of up to 20% in the area of fiber material preparation, assuming that the special digestive energy, digestion and formation / mottling are linearly related to each other.

  The fibrous web has an upper side 27 and a lower side 28 arranged opposite to the upper side 27.

  The sandwich comprising the upper forming fabric 11, the fiber web 2 and the lower forming fabric 10 is guided over the wire section roll 13 before the upper forming fabric 11 is disengaged from the upper side 27 of the fiber web 2, The lower side 28 is arranged on the bottom forming fabric 10 and led to the press section 4.

  Due to the configuration of the forming section 3 described above, the fiber web 2 is optimally dewatered, and at the end of the forming section 3, a dryness of 18% to 20% of the fiber web 2 is achieved even at a speed of 2000 m / min. Can do.

In order to ensure a sufficiently high dewatering rate in combination with the low moisture content and fine surface of the paper, the upper and lower forming fabrics 11 and 10 have a fabric thickness of less than 0.7 mm and more than 1500 / cm ² fibers. And the number of support points.

  At the end of the forming section 2, the fibrous web 2 is conveyed from the lower forming fabric 10 to the press felt 20 of the press section 4 by a pick-up roll 24.

  By means of the press felt 20, the fiber web 2 is guided over the first press nip 14 in the sandwich between the press felt 20 and the press felt 19, with the upper side 27 being guided to the first press nip 14 of the three-nip press 13.

  The 3-nip press 13 has a central roll 21 that forms a second press nip 15 with a roll 25 and forms a third press nip 16 with a roll 26.

  When passing through the second press nip 15, the upper side 27 of the fiber web 2 contacts the press felt 20, and the lower side 28 of the fiber web 2 contacts the smooth peripheral surface of the central roll 21.

  When passing through the third press nip 16, the upper side 27 of the fiber web 2 contacts the press felt 22, and the lower side 28 of the fiber web 2 contacts the smooth peripheral surface of the central roll 21. The third press nip 16 constitutes the second press nip from the end of the press section 4.

  Next, the fibrous web 2 passes through a single press nip 17 of an independent press 18. The press nip 17 forms the last press nip of the press section 4.

  When passing through the press nip 17, the upper side 27 of the fiber web 2 contacts the smooth peripheral surface of the press roll 29, and the lower side 28 of the fiber web 2 contacts the press felt 23.

  Thus, the fiber web 2 is continuously calendered in the two last press nips 16, 17 of the press section 4 on both sides 27, 28 with low dryness, which is on each side 27 of the fiber web 2. 28 is brought into contact with the smooth side and guided through one of the press nips 16,17. Thus, in the two last press nips 16, 17, macrocalendering of the sides of the fiber web 2 takes place, which considerably improves the function of being calendered in the subsequent calendering device.

  In order to be able to reach higher production speeds, it is necessary to increase the dryness after the press section, for example to prevent the fiber web from overstretching and breaking due to web tension. Thus, the penultimate press nip 16 and / or the final press nip 17 can optionally be configured as a shoe press nip. Furthermore, as a result of the longer residence time of the fiber web 2 in the shoe press nip, the calendar effect is increased compared to the conventional press nip.

  In order to calender the fiber web 2 in successive steps in an online process (online calendering), the mass per unit area and the width direction characteristics of moisture are very necessary, which is a high speed calendering speed compared to the offline process. For. Therefore, to correct the moisture distribution in the width direction of the fiber web 2, after the press section 4, a damping agent is selectively applied to the fiber web 2 at least once in the width direction with a moisture content of less than 50%. can do.

  After the press section 4, in this embodiment, a plurality of drying cylinders 30 are arranged in a row, and the fiber web 2 is conveyed to the drying section 5 whose length is not completely illustrated.

  After drying the fibrous web 2 in the drying section 5, it is fed to an on-line multi-nip calendering device 6.

  Upon exiting the drying section 5, the fibrous web has a moisture content that is lower than the equilibrium moisture content at normal climatic conditions. The fibrous web 2 has a moisture content of about 2.5%. Prior to entering the calendering device 6, the fiber web 2 is selectively humidified in the width direction, so that the fiber web 2 has a uniform moisture content of about 8% across the web width.

  Humidification is carried out on the lower side 28 of the fiber web 2 by means of a nozzle humidifier 35 which is configured as a two-component nozzle humidifier and from which a mixture of air-damping agents is ejected.

  The process steps described above in which the overdried fiber web 2 is later rehumidified before entering the multinip calender 6 are advantageous, especially in experiments with fiber materials with a high proportion of fines. This is because this method significantly reduces or prevents defects in dimensional stability such as roughening and fluting. As a result of selective humidification in the width direction, fluctuations in the moisture distribution in the width direction are compensated.

  The on-line multi-nip calendering device 6 has six elastic rolls 31 and four heated rolls 32, which form eight calendering nips 33 and one calendering nip 34.

  The same processing is performed on both sides of the fiber web 2 by the calendering device 6. This is because first the lower side 28 of the fibrous web 2 is in contact with one of the heated rolls 32 in each case within a first sequence 37 of four calendar nips 33 and subsequently further inversion nips. After passing through the calendar nip 34 designated in FIG. 1, the upper side 27 of the fiber web 2 is brought into contact with one of the heated rolls 32 in each case within a second sequence 38 consisting of four calendar nips 33. Is done.

  After exiting the first sequence 37 of the calendar nip 33 and before entering the second sequence 38 of the calendar nip 38, the upper 27 of the fiber web 2 is configured as a two-component nozzle humidifier. Humidification is performed by the humidifier 36. After this humidification, the fibrous web 2 has a moisture content of about 8%.

  Further, steam humidifiers 39 to 41 are provided to give the fiber web 2 a necessary amount of moisture.

  The modification shown in FIG. 2 is substantially the same as the embodiment of FIG. However, the independent press 18 is not provided here. Instead, an impact dryer 42 is provided after the 3 nip press 13. This includes a first vacuum drying cylinder 43 and a second vacuum drying cylinder 44 disposed opposite the first vacuum capable cylinder. Further, the impact drying device 42 includes a fabric 55 that covers a part of the first drying cylinder 43 and a fabric 56 that covers a part of the second drying cylinder 44. In the impact drying device 42, the fiber web 2 is not guided between the fabrics 55 and 56 surrounding the drying cylinders 43 and 44, respectively, so that the fiber web 2 is not pressed against the drying cylinders 43 and 44 by these fabrics. As a result, there is a possibility of causing problems with web guidance. The guidance of the fibrous web 2 through the impact drying device 42 is improved by exhausting the two drying cylinders 43 and 44. The two fabrics 55 and 56 are each formed as a mesh. The first drying cylinder 43 is provided with a hot air hood 45 disposed on the upper side, and the second drying cylinder 44 is provided with two hot air hoods 46 disposed on the lower side. Directly directed to 2 and subsequently does not penetrate the fiber web 2 and is reflected by this fiber web, contrary to the TAD principle. In this way, the drying performance is significantly improved. In the impact dryer 42, hot air is directed directly to the fibrous web 2 by the hot air hoods 45 and 46 without any fabric in between.

  A conveyor belt 47 is wound around the central roll 21 and is guided with the paper web 2 through the second and third press nips 15, 16. The fiber web 2 is separated from the transport belt 47 by the suction roll 48 and is transported to the first drying cylinder 43. A felt belt 49 is wound around the suction roll 48 and is guided further around the three web guide rolls 50.

  From the first drying cylinder 43, the fiber web 2 is conveyed directly to the second drying cylinder 44. From this second drying cylinder, the fibrous web 2 passes over the roll 51 and the suction roll 52 into the drying section 5. In this case, the dryer felt 53 of the drying section 5 covers around the suction roll 52. Only the first two drying cylinders 30 of the drying section 5 are shown.

  Finally, the two drying cylinders 43 and 44 are evacuated via a stabilizer 54 arranged on the opposite side of the impact hoods 45, 46 outside the two drying cylinders 43, 44, respectively. These stabilizers 54 are respectively disposed in a loop formed by the first drying cylinder 43 and the fabrics 55 and 56 that respectively cover a part of the second drying cylinder 44 of the impact drying device 42. Furthermore, the web guide rolls 57 and 58 are each provided with a loop.

1 shows a schematic diagram of a paper machine for carrying out the method according to the invention. The modification of FIG. 1 is shown.

Claims (42)

A method of producing a paper or other fiber web that is pressured at the last press nip after the last press nip in the press section, comprising:
When passing through the penultimate press nip, one side of the fibrous web contacts a smooth surface, and when passing the final press nip, the other side of the fibrous web contacts a smooth surface. A method characterized by that.   The method of claim 1, wherein the smooth surface is formed of a roll shell having a smooth cover and / or a smooth conveyor belt.   The method of claim 2, wherein the conveyor belt is permeable or impermeable.   The press section comprises a three nip press having a central roll and an independent press having a single nip, the third nip of the three nip press being the second press nip from the end of the press section, The method according to claim 1, wherein the single nip is the last press nip of the press section.   5. The method of claim 4, wherein the fibrous web is transported along with a transport belt through second and third press nips formed between a center roll and a press roll of a 3-nip press.   One side of the fibrous web is brought into contact with the conveyor belt and guided through the second-to-last press nip, and the other side of the fibrous web is brought into contact with the press felt and the second-most press nip. A method according to any one of claims 2 to 5, characterized in that it is guided through   One side of the fibrous web is brought into contact with the peripheral surface of the roll, in particular the central roll, through the penultimate press nip and the other side of the fibrous web is in contact with the press felt and penultimately. The method according to claim 2, wherein the method is guided through a press nip.   One side of the fiber web is brought into contact with the press felt and led through the last press nip, and the other side of the fiber web is brought into contact with the peripheral surface of the press roll and led through the last press nip. The method according to any one of claims 1 to 7.   9. The method according to claim 1, wherein the penultimate press nip and / or the final press nip is formed as a shoe press nip.   10. A method according to any one of the preceding claims, wherein the fibrous web is guided through four press nips in a press section.   The method according to any one of claims 2 to 10, wherein the fiber web is transported from the transport belt to a press felt of a final press nip by a transport suction roll.   The method according to claim 11, wherein the transporting suction roll has a peripheral surface covered with rubber and / or a hole pattern in the peripheral surface.   13. A method according to claim 11 or 12, characterized in that the penetration depth of the conveying suction roll with respect to the conveying belt and the fiber web is adjustable.   In order to modify the moisture distribution in the width direction of the fiber web, preferably after the press section, a damping agent is selectively applied to the fiber web at least once in the width direction when the moisture content is less than 50%. 14. A method according to any one of the preceding claims, characterized in that   A damping agent is selectively applied to the fibrous web at least once in the width direction in the forming section and / or the press section in order to modify the widthwise moisture characteristics of the fibrous web. 15. The method according to any one of 14.   16. A method according to any one of the preceding claims, characterized in that the fibrous web is formed in a gap former, in particular a twin wire former.   The method according to claim 16, characterized in that the gap former has a flexible formation foil, preferably 1 to 10 formation foils, particularly preferably 3 to 5 formation foils.   The method according to claim 16 or 17, wherein the gap former is a vertical gap former.   The method according to any one of claims 16 to 18, characterized in that the wrapping angle of the forming roll by the two forming fabrics is in the range of 30 ° to 60 °, preferably 40 ° to 55 °.   18. The formation foil is pressed against a sandwich comprising two forming fabrics with a fibrous web in between, with a contact pressure in the range of 5 Kpa to 30 Kpa, preferably 8 Kpa to 25 Kpa. The method as described in any one of -19. A fabric thickness of less than 0.7 mm, preferably less than 0.65 mm, and a number of fiber support points greater than 1400 / cm ² , preferably greater than 1500 / cm ² , particularly preferably greater than 1600 / cm ² 21. A method according to any one of claims 16 to 20, characterized in that a forming fabric is used.   22. A method according to any one of the preceding claims, wherein after running through the press section, the fibrous web is dried in a drying section.   23. The method of claim 22, wherein after running through the press section, the fibrous web is impact dried.   Said press section (4) simply comprises three press nips (14, 15, 16) and an impact drying device (42) is arranged between the press section (4) and the drying section (5). 24. The method of claim 23, wherein:   25. The three press nips (14, 15, 16) are formed by a three nip press (13) having a central roll (21) and two press rolls (25, 26). The method described in 1.   26. A method according to claim 24 or 25, wherein the first and / or third press nip (14, 16) is formed as a shoe press nip.   27. A method according to any one of claims 24 to 26, wherein the impact dryer (42) is configured as a high dryer.   28. Method according to any one of claims 24 to 27, characterized in that at least one drying cylinder (43, 44) of the impact drying device (42) is slightly evacuated.   29. Method according to claim 28, characterized in that a stabilizer (54) is used to evacuate the drying cylinder (43, 44).   30. A method according to any one of the preceding claims, wherein following the drying in the drying section, the fibrous web is fed to a multi-nip calendering device.   The method of claim 30, wherein the multi-nip calendering device is an on-line calendering device.   32. A method according to any one of the preceding claims, wherein the moisture content of the fibrous web is lower than the equilibrium moisture content under normal climatic conditions when leaving the drying section.   The method of claim 32, wherein the fibrous web is humidified prior to entering the calendering device.   The method of claim 33, wherein the fibrous web is selectively humidified in the width direction.   One of the two sides of the fibrous web is in each case contacted with the heated roll of the first sequence of nips, and the other of the two sides of the fibrous web is in each case the second of the nips. 35. A method according to any one of claims 30 to 34, wherein the method is contacted with two sequences of heated rolls.   36. The method according to claim 35, wherein the side of the fibrous web that is in each case contacted with the heated roll is humidified before each nip sequence.   37. A method according to claim 36, characterized in that the fibrous web is humidified to a moisture content of 7% to 9%, particularly preferably a moisture content of 8%.   38. Before entering a calendering device, the fibrous web is preferably humidified to a moisture content of 7% to 9%, particularly preferably a moisture content of 8%. The method according to item.   39. The method of claim 38, wherein the fibrous web is humidified on both sides prior to entering the calendering device.   40. A method according to any one of claims 36 to 39, wherein the fibrous web is humidified by a steam humidifier and / or a nozzle humidifier.   41. A method according to any one of claims 1 to 40, wherein the fiber web produced is gravure paper (SC or SCA + paper).   42. A method according to claim 41, wherein the gravure paper has a filler content of 25% or more, preferably 30% or more.

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