JP2012224968A - Papermaking felt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a papermaking felt which is treated with a resin and maintains appropriate air permeability so as to have excellent water-squeezing capability.SOLUTION: A papermaking felt 100 includes a base fabric 1, a front batt layer 2 laminated on the papermaking surface of the base fabric 1, and a rear batt layer 3 laminated on the traveling surface of the base fabric 1. In the thickness direction of the front batt layer 2, at least one layer of a resin loss preventing woven fabric 4 is disposed. The resin loss preventing woven fabric 4 has a mesh size of 0.5-3.0 mm. At least the front batt layer 2 and the resin loss preventing woven fabric 4 are treated with a resin. It is preferable that the front batt layer 2 includes a front inner batt layer 21 laminated on the base fabric 1 and a front outer batt layer 22 laminated on the front inner batt layer 21, and that the resin loss preventing woven fabric 4 is interposed between the front inner batt layer 21 and the front outer batt layer 22.

Description

  The present invention relates to a papermaking felt. More specifically, the present invention is processed with a resin, particularly a water-based resin, and the attached resin is less likely to drop off and maintains a proper air permeability, so that a papermaking felt that maintains excellent water squeezability. About.

  Conventionally, in the papermaking process, wet paper is dehydrated by a papermaking wire at the wire part and transported to the press part, and the wet paper whose surface is smoothed is squeezed by the papermaking felt at the press part. Transported and paper-made. In the press part, the wet paper running between the press rolls or between the press roll and the pressure shoe having a curved surface approximate to the peripheral shape of the press roll is pressurized and squeezed. In this case, only the wet paper does not travel between the press rolls or between the press roll and the pressure shoe. For example, from one press roll or the pressure shoe side, the paper making belt, the paper making felt and the wet The paper is run and squeezed with the papers laminated in this order, and the surface is smoothed.

  Conventionally, as a felt for papermaking, a product in which a woven fabric in which warps and wefts are crossed so that a knuckle portion is formed is used as a base fabric, and bat fibers are laminated on both sides of this base fabric is often used. ing. In addition, there is a need for further improvement in productivity by improving the quality of the paper to be made and speeding up the paper making speed, and more various properties such as water squeezing, surface smoothness, hair removal resistance, antifouling resistance, etc. Development of a papermaking felt having excellent characteristics is demanded, and in recent years, the use of a resin processing felt obtained by applying a resin processing to a papermaking felt is increasing.

As a papermaking felt, products having various structures have been developed. For example, a base layer, a first butt layer formed on the wet paper side of the base layer, a second butt layer formed on the press side, A paper transporting felt is provided that includes a wet paper web contact fiber layer formed on the wet paper web side of one vat layer, and a hydrophilic nonwoven fabric layer disposed between the first batt layer and the wet paper web contact fiber layer. (For example, refer to Patent Document 1). Further, it is described that a press device provided with this papermaking felt is easy to remove dirt, has good paper separation, and has excellent wet paper surface smoothness. Further, a press cloth for a press section of a paper machine, comprising: a base support structure; a first short fiber cotton material bonded to the outside; and a second short fiber cotton material covering the cotton material. A press cloth that is excellent in water squeezing and prevents rewetting of paper is known (for example, see Patent Document 2).

Further, as the resin processed felt, the resin is impregnated from the bat fiber layer to the base fabric in a state of being dispersed in the bat fiber layer, the air permeability is 2 m ³ / m ² · min or more, and the surface is polished. The press felt and its manufacturing method are known (for example, refer to Patent Document 3). According to this press felt, the water pressing, the surface smoothness, the compression resistance are excellent, and the effect of improving the familiarity. Has been explained.

JP 2006-97181 A JP 2006-506552 A JP 2005-524002 Gazette

  In the paper transporting felt described in Patent Document 1, effects such as easy removal of stains are exhibited, and when the resin is processed, the resin adheres to the hydrophilic nonwoven fabric layer, and the early drop-off is also suppressed. Although it may be played, it is presumed that it is not sufficient (note that the paper transporting felt described in Patent Document 1 is not a resin processing felt, and there is no description regarding prevention of falling off of the resin). Moreover, since the paper transporting felt described in Patent Document 1 uses a nonwoven fabric composed of fibers of 4 dtex or less that are thinner than bat fibers, the mesh is very fine and the air permeability is low. Therefore, it can be expected to prevent re-wetting of the water squeezed from the wet paper back to the wet paper, and as a resin stopper layer when impregnated with resin from the surface. The problem that it is easy to accumulate and the problem that it is difficult to impregnate the resin up to the base fabric are conceivable. In particular, if the amount of resin is large, more than necessary resin is impregnated in the vicinity of the nonwoven fabric surface and densely packed, causing clogging of clogs, and further causing problems such as deterioration of air permeability and accumulation of dirt. It may cause a decrease in felt water extraction performance.

  Furthermore, although the press cloth for the press section of the paper machine described in Patent Document 2 is not a resin processing felt, the opening of the fine cloth used is 0.5 mm or less. It is conceivable that the air permeability becomes insufficient and the squeezing ability is lowered. In addition, the press felt described in Patent Document 3 can be expected to have an effect of improving the initial familiarity and water squeezing, but there is a concern that the resin may fall off during use. In particular, when the resin is a water-based resin and when a vat fiber having a high fineness is used, it is assumed that the resin is more easily dropped.

  The present invention has been made in view of the above-described state of the art, and is processed using a resin, particularly an aqueous resin, so that the attached resin is less likely to fall off, and appropriate air permeability is maintained. An object of the present invention is to provide a papermaking felt in which excellent water squeezability is maintained.

The present invention is as follows.
1. A felt for papermaking comprising a base fabric, a front bat layer laminated on a papermaking surface of the base fabric, and a back bat layer laminated on a running surface of the base fabric,
In the front bat layer, at least one layer of the resin detachment preventing woven fabric is disposed in the thickness direction of the front bat layer, and the scale of the resin detachment preventing woven fabric is 0.5-3. A felt for papermaking, characterized in that it has a thickness of 0.0 mm and at least the front butt layer and the woven fabric for preventing resin dropping are resin-processed.
2. The outer bat layer has an inner bat layer laminated on the base fabric and an outer bat layer laminated on the inner bat layer. 1. Interposed between the outer layer and the outer bat layer. Papermaking felt as described in 1.
3. The outer bat layer has an inner bat layer laminated on the base fabric and an outer bat layer laminated on the inner bat layer. The 1. disposed in the layer. Papermaking felt as described in 1.
4). 2. The fineness of the fibers constituting the inner bat layer is 27 to 100 dtex. Or 3. Papermaking felt as described in 1.
5. 1. The resin used for the resin processing is an aqueous resin. To 4. The papermaking felt according to any one of the above.
6). 1. The thickness of the resin detachment preventing woven fabric is 0.1 to 0.5 mm, and the basis weight is 10 to 100 g / m ² . To 5. The papermaking felt according to any one of the above.
7). The yarn that constitutes the woven fabric for preventing resin dropping has fluff on the surface. To 6. The papermaking felt according to any one of the above.
8). At least one of the warp and the weft constituting the resin detachment preventing woven fabric is at least one of spun yarn, multifilament twisted yarn and multifilament non-twisted yarn. To 7. The papermaking felt according to any one of the above.
9. At least one of the warp and the weft constituting the resin detachment preventing woven fabric is at least one of a hydrophilic yarn and a hydrophilic processed yarn. To 8. The papermaking felt according to any one of the above.

According to the felt for papermaking of the present invention, a resin detachment preventing woven fabric (hereinafter referred to as “additional woven fabric”) having a specific texture in the front bat layer is interposed or disposed, When resin processing is performed, the resin is impregnated to the inside of the felt, that is, the resin is impregnated to the lower part of the additional woven fabric and the base fabric, and the resin adhering to the thread etc. does not easily fall off, and appropriate air permeability is maintained. Therefore, excellent water squeezing is maintained, and the shape of the additional woven fabric is not transferred, and marks such as irregularities are not generated on the surface of the wet paper.
The outer bat layer has an inner bat layer laminated on the base fabric and an outer bat layer laminated on the inner bat layer, and the additional woven fabric has an inner bat layer and an outer bat layer. In the case of being interposed between the two, the excellent water squeezing is maintained, and the generation of marks such as irregularities on the surface of the wet paper is more reliably prevented.
Furthermore, the front bat layer has an inner bat layer laminated on the base fabric and an outer bat layer laminated on the inner bat layer, and the additional woven fabric is disposed in the inner bat layer. In this case, since the additional woven fabric is disposed at a position farther from the surface of the wet paper, the generation of marks such as irregularities on the surface of the wet paper is particularly reliably prevented.
In addition, when the fineness of the fibers constituting the bat layer in the table is 27 to 100 dtex, the bat has a rough structure, and thus the resin used for the resin processing usually tends to fall off, but a specific additional woven fabric is used. By arranging or disposing, even if the fineness of the fibers constituting the in-table bat layer is large, the resin is sufficiently prevented from falling off and excellent water squeezing is maintained.
Furthermore, when the resin used for the resin processing is a water-based resin, a resin solution in which water is the main component of the solvent can be used, and the resin can be easily attached to the inner bat layer and the like, and organic Since it is not a solvent, it is preferable from an environmental viewpoint. Conventionally, water-based resins are more likely to fall off and have a problem with durability. However, in the papermaking felt of the present invention, by providing an additional woven fabric, dropping is sufficiently suppressed even with water-based resins. There is no problem in durability.
Further, when the thickness of the additional woven fabric is 0.1 to 0.5 mm and the basis weight is 10 to 100 g / m ^2, it is possible to sufficiently prevent the resin from falling off, and on the wet paper surface. Generation of marks such as irregularities can be prevented more reliably.
Furthermore, when the yarn constituting the additional woven fabric has fluff on the surface, the resin can be further prevented from falling off by adhering to the fluff portion. In addition, the fluff becomes entangled with the bat fibers on both sides of the additional woven fabric during needling, and a state in which a coarse structure and a fine structure are mixed is obtained, so that water squeezing can be further improved.
Further, when at least one of the warp and the weft constituting the additional woven fabric is at least one of spun yarn, multifilament twisted yarn and multifilament non-twisted yarn, the resin used for the resin processing is held by the yarn. It is easy and the dropping of the resin is more sufficiently suppressed.
Further, when at least one of the warp and the weft constituting the additional woven fabric is at least one of a hydrophilic yarn and a hydrophilic processed yarn, the resin is used particularly when the resin used for the resin processing is an aqueous resin. The additional woven fabric easily adheres and is more difficult to drop off, and maintains moderate air permeability, so that excellent water squeezability is maintained.

It is a schematic diagram of the cross section of the felt for papermaking in which the additional woven fabric is interposed between the inner bat layer and the outer bat layer. It is a schematic diagram of the cross section of the papermaking felt in which the additional woven fabric is disposed in the bat layer in the front. It is a typical top view of the additional woven fabric which does not have fluff. It is a typical top view of the additional woven fabric which has a fluff. It is explanatory drawing based on the electronic data of the additional woven fabric which has a fluff. It is a schematic diagram for demonstrating the apparatus which evaluates the performance of the felt for paper manufacture.

Hereinafter, the present invention will be described in detail with reference to FIGS.
The papermaking felts 100 (see FIG. 1) and 200 (see FIG. 2) of the present invention are laminated on the base fabric 1, the front bat layer 2 laminated on the papermaking surface of the base fabric 1, and the running surface of the base fabric 1. And at least one additional woven fabric 4 is disposed in the thickness direction of the front bat layer 2, and the additional woven fabric 4 has a mesh of 0.5 to 3. 0 mm, and at least the front bat layer 2 and the additional woven fabric 4 are resin-processed.

  As the “base fabric 1”, a general base fabric used for a papermaking felt can be used. The yarn constituting the base fabric 1 is not particularly limited. For example, monofilament, multifilament, spun yarn, textured yarn subjected to crimping processing, bulky processing, etc., processed yarn such as bulky yarn and stretch yarn, and these A twisted yarn obtained by twisting various types of yarns can be used. The cross-sectional shape of the yarn is not particularly limited, and is not limited to a circular shape, and may be a substantially elliptical shape, a substantially square shape, a substantially star shape, a substantially rectangular shape, or the like, and a hollow fiber may be used.

  The material of the yarn constituting the base fabric 1 is also not particularly limited. For example, polyamide resins such as 6 nylon, 66 nylon, 610 nylon, and 612 nylon, polyester resins such as polyethylene terephthalate and polybutylene terephthalate, and polyolefins such as polyethylene and polypropylene Examples include various synthetic resins such as resins, and cotton, wool, silk and the like. Among these, a polyamide resin that can be used as a papermaking felt having excellent wear resistance, compression recovery, impact resistance, and the like is preferable. Further, a copolymer resin can be used, and a synthetic resin containing various additives can be used according to required physical properties. Only one type of yarn constituting the base fabric may be used, or two or more types of yarn may be used in combination.

The fineness of the yarn constituting the base fabric 1 is not particularly limited, and yarns having various finenesses can be used according to the required characteristics of the papermaking felts 100 and 200. The fineness of the yarn constituting the base fabric 1 is usually 100 to 6000 dtex, preferably 120 to 3500 dtex, and particularly preferably 140 to 2500 dtex. When it is a multifilament, the fineness of the monofilament which comprises this multifilament is 1-20 dtex normally, and it is preferable that it is 3-15 dtex. The number of yarns constituting the multifilament is usually 250 or less, and can be 20 to 250. Although the basis weight of the base fabric 1 is not particularly limited, usually, a 250~1300g / ^{m 2,} it is preferable that 350~1200g / ^{m 2.}

  Although the thickness of the base fabric 1 is not particularly limited, it is usually 0.5 to 6 mm, and can be 0.7 to 5 mm, particularly 0.9 to 4.5 mm. Further, the structure of the base fabric 1 is not particularly limited, and may be a single layer structure (single weave), and is formed by a method of weaving two or more warp yarns or two or more weft yarns. In addition to the single woven or multiple woven fabric, a nonwoven fabric in which yarns are arranged in the warp direction, the weft direction, or the oblique direction can also be used. Moreover, the laminate (lamination | stacking) structure which laminated | stacked each base fabric may be sufficient. As this laminate structure, any combination of the woven fabric and the nonwoven fabric may be used. By adopting such a laminate structure, the durability of the papermaking felts 100 and 200 can be improved.

The “surface bat layer 2” laminated on the papermaking surface of the base fabric 1 may be composed of bat fibers, and may be composed of only one bat fiber layer, or two or more layers of bat fibers. You may be comprised by the layer. The material of the front bat layer 2 is not particularly limited, and examples thereof include various synthetic resins such as a polyamide resin, a polyester resin, and a polyolefin resin that constitute the base cloth 1. The fineness of the bat fiber is not particularly limited, and can be 6 to 100 dtex, and particularly preferably 10 to 70 dtex. Also, the basis weight of the front batt layer 2 is not particularly limited, may be a ^{100~1500g / m 2, 200~1200g / m} 2, it is preferred that particularly 300~900g / ^{m 2.}

The “back bat layer 3” laminated on the running surface of the base fabric 1 may also be composed of bat fibers, and may be composed of only one bat fiber layer, or two or more layers of bat fibers. You may be comprised by the layer. The material of the back bat layer 3 and the fineness of the fibers can be the same as those of the front bat layer 2. Also, the basis weight of the back batt layer 3 is not particularly limited, 50 to 400 g / ^{m 2,} and it is possible to, 60~380g / ^{m 2,} it is preferred that particularly 70~350g / ^{m 2.}

  In the papermaking felts 100 and 200 of the present invention, at least one “additional woven fabric 4” (see FIG. 3) is disposed in the thickness direction of the front bat layer 2, and the base fabric 1 and the front bat layer 2 are disposed. The laminated body including the back bat layer 3 and the additional woven fabric 4 is formed, and thereafter, at least the front bat layer 2 and the additional woven fabric 4 are subjected to resin processing. The method of resin processing is not particularly limited, but after impregnating various resins, particularly aqueous resin solutions, from the surface bat layer 2 side, the medium is removed by heating to add the resin to the surface bat layer 2 and addition. It can be attached to the woven fabric 4 or the like.

  The resin used for the resin processing is not particularly limited, but an aqueous resin can be used, and the aqueous resin is classified into one of forced emulsification type, self-emulsification type, and water-solubilization type, for example, polyurethane resin , Acrylic resin, epoxy resin, or a mixture thereof. By this resin processing, the thickness of the papermaking felt is slightly reduced as compared with that before the processing, and the porosity is maintained by the adhered resin. Thereby, it can be set as the felt for paper manufacture which has the water squeezing etc. which were excellent from the beginning of use, and this outstanding water squeezing is maintained.

  The mesh (length of one side of the mesh) of the additional woven fabric 4 is 0.5 to 3.0 mm, 0.6 to 3.0 mm, particularly 0.7 to 2.8 mm, and further 0.8 to 2 .6 mm is preferred. If the texture of the additional woven fabric 4 is 0.5 to 3.0 mm, particularly 0.6 to 3.0 mm, the felt 100 for papermaking having an appropriate air permeability and excellent water squeezing after resin processing. 200, and can also be used for applications such as paperboard with a large amount of squeezed water. When the mesh size is less than 0.5 mm, the air permeability is greatly reduced, so that the water squeezing is also reduced, and further, the accumulation of dirt during use is increased, so that the air permeability is further lowered and the water squeezing is reduced. The problem of having an adverse effect also occurs. In addition, when the mesh exceeds 3.0 mm, there is a problem that the effect of preventing the additional woven fabric 4 from falling off the resin is greatly reduced. In addition, as shown in FIGS. 3 and 4, the term “mesh” refers to the range of the quadrilateral formed by the inner sides of each of the constituent yarns 41 and 42 of the additional woven fabric 4 (inside the quadrilateral indicated by the symbol A). The length of one side of the mesh means any length of the four sides of the quadrilateral (for example, the length of one side of the mesh is the side indicated by the symbol a in FIG. It is the length of each of the other three sides.)

Although the thickness of the additional woven fabric 4 is not specifically limited, it can be 0.1-0.7 mm, 0.1-0.6 mm, especially 0.1-0.5 mm, Furthermore 0.15-0. 5 mm is preferable. Although the basis weight of the additional fabric 4 is not particularly limited, may be a ^{10~110g / m 2, 10~100g / m} 2, in particular 15 to 100 / ^{m 2,} to be more 20~95g / ^{m 2} preferable. If the thickness of the additional woven fabric 4 is 0.1 to 0.7 mm, particularly 0.1 to 0.5 mm, and the basis weight is 10 to 110 g / m ² , particularly 10 to 100 g / m ² , an aqueous resin Is easy to penetrate, resin processing is easy, and dropping of the resin can be sufficiently suppressed. Furthermore, it is possible to more reliably prevent the occurrence of marks such as irregularities on the surface of the wet paper.

  Moreover, it is preferable that the thread | yarn which comprises this additional woven fabric 4 has the fluff 4a (refer FIG. 4, 5) on the surface. If the yarn has the fluff 4a, the fluff 4a and the bat fiber can be entangled by laminating the batt fiber on both sides of the additional woven fabric 4 and performing needling. If it does in this way, resin will fully adhere to the part where fluff 4a etc. became entangled, and it can improve the resin omission prevention effect further. Moreover, it will be in the state where a coarse structure | tissue and a fine structure | tissue were mixed, and the squeezing ability of the felts 100 and 200 for papermaking can be improved more.

  Furthermore, since the yarn constituting the additional woven fabric 4 has the fluff 4a on the surface, the intersection of the yarn (fluff 4a) and the bat fiber increases, and the resin used for the resin processing adheres to the intersection, A surface bat layer 2 having a three-dimensional structure in which resin is distributed in the vertical direction can be obtained. Moreover, even if it is a nonwoven fabric with a rough structure | tissue, a porous structure provided with the communicating hole of a more appropriate diameter is formed by resin adhering to the said intersection, and water squeezing can fully be improved. The method for forming the fluff 4a is not particularly limited, and the surface of the additional woven fabric 4 may be rubbed with sandpaper, a metal brush, or the like, or may be fluffed using a raising machine. The length of the fluff is not particularly limited, but the length of the fluff relative to the length of one side of the mesh (100%) is preferably 10 to 200%, particularly preferably 30 to 80%. With such a length of fluff, the effect of having the fluff is sufficiently exerted, and the mesh is not blocked. Further, the fluff preferably accounts for 10 to 90%, particularly 20 to 80%, of the mesh area (100%) on average when the additional woven fabric is viewed in plan. If the area ratio which a fluff occupies is in the above-mentioned range, the effect by having a fluff is fully show | played, and a scale is not obstruct | occluded.

  The material of the yarn constituting the additional woven fabric 4 is not particularly limited. For example, various synthetic resins such as polyamide resin, polyester resin, polyolefin resin and the like constituting the front bat layer 2 and the back bat layer 3, cotton, Examples include wool and silk. Among these, a polyamide resin that can be used as a papermaking felt having excellent wear resistance, compression recovery, impact resistance, and the like is preferable. Further, a copolymer resin can be used, and a synthetic resin containing various additives can be used according to required physical properties. Only one type of yarn constituting the additional woven fabric 4 may be used, or two or more types of yarn may be used in combination.

  The type of yarn constituting the additional woven fabric 4 is not particularly limited, and various yarns can be used, but at least one of the warp and weft constituting the additional woven fabric 4, preferably both the warp and the weft, are spun yarns. It is preferably at least one of a multifilament twisted yarn and a multifilament non-twisted yarn. If the additional woven fabric 4 is composed of the above-described various yarns, the aqueous resin solution easily permeates due to the capillary phenomenon, and the aqueous resin solution adhering to the surface bat layer 2 near the additional woven fabric 4 is also absorbed, and the surface of the yarn Thus, the resin layer is formed, and the resin is more reliably prevented from falling off.

  Moreover, it is preferable that at least one of the warp and the weft constituting the additional woven fabric 4, preferably both the warp and the weft, be at least one of a hydrophilic yarn and a hydrophilic processed yarn. Examples of the hydrophilic processed yarn include yarn obtained by subjecting a hydrophobic resin such as polyester resin and polyolefin resin to hydrophilic processing. The hydrophilic processing method is not particularly limited, and examples thereof include various methods such as graft polymerization treatment, sulfonation treatment, and fluorine gas treatment of a hydrophilic vinyl monomer.

  The additional woven fabric 4 only needs to be disposed in the thickness direction of the surface bat layer 2, and the number of layers of the additional woven fabric 4 is not particularly limited, but is 1 to 3 layers, particularly 1 to 2 layers. It can be. In addition, usually only one layer needs to be provided, and even if only one layer is provided, the above-described operational effect by providing the additional woven fabric 4 is sufficiently exhibited. Furthermore, since the additional woven fabric 4 has a large mesh size, the air permeability is not greatly reduced even when a plurality of layers are provided or thickened compared to the case where a nonwoven fabric is additionally provided as in the conventional case. . Further, the entanglement with the bat fiber due to needling does not decrease. Therefore, the resin penetrates sufficiently, and the resin can be reliably prevented from falling off.

  Further, the arrangement position of the additional woven fabric 4 in the thickness direction of the front bat layer 2 is not particularly limited, but when it is on the papermaking surface side, irregularities formed by transferring the shape of the additional woven fabric 4 to the surface of the wet paper. Since this mark is generated, the base fabric 1 side is preferable from the middle portion in the thickness direction. For example, when the outer bat layer 2 has an inner bat layer 21 laminated on the base fabric 1 and an outer bat layer 22 laminated on the inner bat layer 21, the additional woven fabric 4 has an outer bat layer Rather than being arranged in the layer 22, it is preferable to interpose between the inner bat layer 21 and the outer bat layer 22, or to arrange in the inner bat layer 21.

  When the additional woven fabric 4 is interposed between the inner bat layer 21 and the outer bat layer 22, the outer bat layer 22 is interposed between the additional woven fabric 4 and the wet paper. The occurrence of marks such as irregularities on the surface of the wet paper is prevented. When the additional woven fabric 4 is disposed in the inner bat layer 21, the outer bat layer 22 and the outer bat layer 21 are disposed on the outer side between the additional woven fabric 4 and the wet paper web. Partly intervenes, and generation of marks such as irregularities on the surface of the wet paper is more reliably prevented.

  Furthermore, the ratio of the thickness of the inner bat layer 21 and the outer bat layer 22 is not particularly limited, and can be set as appropriate depending on the basis weight of each layer. Further, the arrangement position of the additional woven fabric 4 in the thickness direction of the inner bat layer 21 is not particularly limited, but an intermediate portion (the base fabric 1 side and the outer bat layer 22 side) of the inner bat layer 21 in the thickness direction. It is preferable to dispose at a middle portion excluding a range of ¼, preferably １ ／ of the total thickness of each.

  The fineness of the bat fiber used for the inner bat layer 21 and the outer bat layer 22 may be the fineness of the bat fiber constituting the aforementioned front bat layer 2. Moreover, the fineness of the bat fiber used for the outer bat layer 21 is usually larger than the fineness of the bat fiber used for the outer bat layer 22. In the case of a resin processing felt, when rough vat fibers are used, particularly when fibers of 27 dtex or more are used, there is a problem that the resin falls off at the initial stage of use in a paper machine. By arranging the additional woven fabric 4 as described above, for example, fibers in the range of 27 to 100 dtex can be used as the fibers constituting the in-table bat layer 21. When the fineness of the fibers constituting the in-table bat layer 21 is large, the bat has a rough structure, and the resin tends to fall off as described above, but the additional woven fabric 4, particularly the additional woven fabric having the fluff 4a. By arranging 4, even if the fineness is as large as 27 to 100 dtex, it is possible to sufficiently prevent the resin from dropping off, and the above-described operational effects by arranging the additional woven fabric 4 are sufficiently exhibited.

  The outer bat layer 22 is directly subjected to mechanical external forces such as repeated compression, shower, suction, etc., so that the resin impregnated and adhered to the outer bat layer 22 tends to fall off compared to the inside. On the other hand, it is necessary to sufficiently prevent the resin that has been impregnated and adhered to the inner bat layer 21 from dropping, but conventionally when the bat fiber of 27 dtex or more is used for the inner bat layer 21, the resin falls off at an initial stage. There was a problem that there was something. In the papermaking felt according to the present invention, such additional problems can be solved by disposing the additional woven fabric 4 and, as described above, the resin can be sufficiently prevented from falling off even when a bat fiber of 27 dtex or more is used. .

  Further, the outer bat layer 22 is composed of a bat fiber having a small fineness to which the resin easily adheres for reasons such as affecting the surface smoothness of the wet paper. Since the outer bat layer 22 is directly subjected to mechanical external force such as press, high pressure shower, suction, etc., it is considered that even if the resin is processed, the resin is easily dropped. In other words, even if the outer bat layer 22 has a sufficient amount of resin attached, its effect is not easily maintained. On the other hand, the inner bat layer 21 is less susceptible to external force than the outer bat layer 22, and the attached resin is less likely to fall off, and the operational effect of the resin processing is maintained for a long time. From this point of view, the additional woven fabric 4 is not disposed in the outer bat layer 22 but is interposed between the inner bat layer 21 and the outer bat layer 22 or the inner bat layer. It is preferable to arrange in 21.

Hereinafter, the present invention will be described specifically by way of examples.
(1) Production of felt for papermaking Examples 1 and 2
A base fabric 1 having a thickness of 1.24 mm and a basis weight of 550 g / m ² using a polyamide resin warp yarn of 1120 dtex and a weft yarn of 1046 dtex, a polyamide resin fiber having a fineness of 17 dtex, and a basis weight of 259 g / m ² . Using an inner bat layer 21, an outer bat layer 22 with a basis weight of 300 g / m ³ , an additional woven fabric 4 with a mesh size of 1.0 mm, a thickness of 0.26 mm, and a basis weight of 41 g / m ² , and a polyamide resin fiber with a fineness of 27 dtex The back bat layer 3 having a basis weight of 200 g / m ² was laminated in this order and integrated by needling.

Thereafter, an aqueous solution in which a urethane resin having a concentration of 3.7% by weight with respect to the felt weight before impregnation with the resin is dissolved is impregnated from the outer bat layer 22 side, and then dried to remove water. Then, the resin was processed by cross-linking to produce a papermaking felt 100 having a thickness of 3.6 mm, a width of 300 mm, a length of 500 mm, and a total basis weight of 1400 g / m ² (see FIG. 1). In addition, the additional woven fabric 4 (refer to the additional woven fabric 4 of FIGS. 4 and 5 having the fluff 4a) (Example 1) and the additional woven fabric 4 that is not fluffed (addition of FIG. 3). (See woven fabric 4) (Example 2).

Comparative Example 1
The felt for papermaking of Comparative Example 1 having the same dimensions and total basis weight as in Examples 1 and 2 except that the inner bat layer 21 having a basis weight of 300 g / m ² was used and the additional woven fabric 4 was not used. Was made.

Examples 3 and 4
Implementation was carried out except that the inner bat layer 21 with a basis weight of 239 g / m ² having a fiber fineness of 27 dtex and an additional woven fabric 4 with a basis weight of 2.3 mm, a thickness of 0.41 mm, and a basis weight of 61 g / m ² was used. In the same manner as in Examples 1 and 2, a papermaking felt 100 having the same dimensions and total basis weight was produced (see FIG. 1). In Example 3, the additional woven fabric 4 was fluffed in the same manner as in Example 1, and in Example 4, the additional woven fabric 4 was not fluffed as in Example 2.

Examples 5 and 6
Example except that the inner bat layer 21 having a basis weight of 268 g / m ² having a fiber fineness of 27 dtex and the additional woven fabric 4 having a basis weight of 0.8 mm, a thickness of 0.18 mm and a basis weight of 32 g / m ² was used. In the same manner as 3 and 4, a papermaking felt 100 having the same dimensions and total basis weight was produced (see FIG. 1). In Example 5, the additional woven fabric 4 was fluffed in the same manner as in Example 3, and in Example 6, the additional woven fabric 4 was not fluffed as in Example 4.

Examples 7 and 8
The inner bat layer 21 with a basis weight of 259 g / m ² having a fiber fineness of 27 dtex and the same additional woven fabric 4 as in Examples 1 and 2 were used. The additional woven fabric 4 was arranged in the thickness direction of the inner bat layer 21. A papermaking felt 200 having the same dimensions and total basis weight was produced in the same manner as in Examples 3 and 4 except that it was disposed in the intermediate portion (see FIG. 2). In Example 7, the additional woven fabric 4 was fluffed in the same manner as in Example 3, and in Example 8, the additional woven fabric 4 was not fluffed as in Example 4.
The scale of the additional woven fabric 4 used in the examples was observed by observing the additional woven fabric 4 at a magnification of 10 using an optical microscope, taking the photographed data into a computer, printing it, and determining the size of the eyes. 10 were randomly measured to obtain an average value, and this average value was calculated by dividing the actual magnification of the photograph.

Comparative Example 2
For comparison with Examples 3 to 8, a papermaking felt in which the fineness of the in-table batt layer 21 of Comparative Example 1 was changed to 27 dtex was produced.
Comparative Example 3
A spunbond nonwoven fabric having a thickness of 0.09 mm and a fabric weight of 20 g / m ² using a fiber made of a polyamide resin instead of the additional woven fabric 4, and an in-table bat having a fabric weight of 27 dtex and a fabric weight of 280 g / m ² A papermaking felt of Comparative Example 3 having the same dimensions and total basis weight was produced in the same manner as in Examples 3 to 6 except that the layer 21 was used.

(2) Evaluation (a) Evaluation of Residual Residue Level The papermaking felts of Examples 1 to 8 and Comparative Examples 1 to 3 were advanced so that each papermaking felt was tested under the same conditions. Connection was made in the length direction so that the directions were the same, and the test was performed using the evaluation apparatus 10 as shown in the schematic diagram of FIG. In the test, the papermaking felt was rotated to the right at a speed of 150 mm / min, the high pressure shower 7 and the suction box 6 were used, and the number of presses was 50000 with a press pressure of 40 kg / cm between the press rolls 51 and 52. It was carried out to run. The results are listed in Table 1.

  The degree of residual resin was evaluated by taking a photograph of the cross section of the papermaking felt after pressing 50000 times and comparing the amount of resin remaining without dropping. However, since the amount of dropped resin cannot be accurately evaluated by the change in weight before and after the test, the resin distribution was compared and evaluated by a cross-sectional photograph. Specifically, in the papermaking felt of Comparative Example 1 in which the fiber fineness of the batt layer in the table is small, the resin is less likely to fall off earlier than in the papermaking felt of Comparative Example 2 in which the fiber fineness is large, and there are many production results. On the basis of Comparative Example 1, the case where the amount of residual resin is smaller than that is ×, the case where the amount is the same is Δ, the case where it is slightly larger is ○, and the case where it is larger is ◎.

(B) Change in air permeability before and after resin processing For each of the papermaking felts of Examples 3, 5, 7 and Comparative Examples 2 and 3, the air permeability before and after resin processing was measured as a Frazier air permeability meter. (Measurement was made using a format “FX3300 Air Permeability Tester III” manufactured by TEXTEST). The rate of change in air permeability was calculated based on the following formula. The results are listed in Table 1.
Change rate of air permeability (%) = (air permeability after resin processing / air permeability before resin processing) × 100
Since the value is calculated based on such a formula, the greater the rate of change, the more the air permeability before resin processing is maintained, and a papermaking felt having excellent water squeezing and the like can be obtained.

  According to the cross-sectional photograph and the results shown in Table 1, in the papermaking felts of Examples 1 to 8 in which the additional woven fabric is interposed, the resin is adhered to the yarn constituting the additional woven fabric, but the resin is continuous. The layer formed was not observed, and it was found that appropriate pores were formed. Further, in Examples 1, 3, 5 and 7 in which the additional woven fabric was fluffed, it was observed that the resin adhered to the portion where the bat and the fluff in the vicinity of the additional woven fabric were entangled. On the other hand, in Comparative Example 2, it was found that the remaining resin was small. Further, in Comparative Example 3 in which the nonwoven fabric was interposed, the resin remained sufficiently, but it was observed that a thin layer of the resin was formed in the nonwoven fabric, and there was concern about a decrease in air permeability.

  In addition to the normal base fabric and bat fiber, a nonwoven fabric or a woven fabric is separately provided, and it is predicted that the air permeability of the papermaking felt subjected to resin processing will be greatly reduced. Therefore, in Examples 3, 5 and 7, it is inferred that the felt for papermaking has high air permeability even after resin processing and has excellent water squeezing. On the other hand, in Comparative Example 3 in which a nonwoven fabric is interposed instead of the additional woven fabric, it can be seen that the decrease in air permeability is larger than that in Comparative Example 2 because the fiber between the nonwoven fabrics is blocked by the resin.

(3) Confirmation of marks on the surface of the felt for papermaking About the felt for papermaking of Examples 1 to 8, the felt for papermaking of Comparative Example 2, and the felt for papermaking of Example 9 below, confirmed. That is, the mark on the surface of the outer bat layer, which was transferred and caused the generation of the mark, was confirmed instead of confirming the mark directly on the surface of the wet paper.
Example 9
Example except that the inner bat layer 21 having a basis weight of 214 g / m ² having a fiber fineness of 27 dtex and the additional woven fabric 4 having a basis weight of 0.9 mm, a thickness of 0.52 mm, and a basis weight of 86 g / m ² was used. In the same manner as in No. 4, a papermaking felt 100 having the same dimensions and total basis weight was produced (see FIG. 1).

  As a result of the confirmation, in Examples 1 to 8, the mark by the additional woven fabric was not observed on the surface of the papermaking felt, and it was the same as Comparative Example 2 in which neither the additional woven fabric nor the nonwoven fabric was interposed. In particular, in Examples 5 and 6 in which the thickness of the additional woven fabric was small and in Examples 7 and 8 in which the additional woven fabric was disposed farther from the paper-making surface side, the surface smoothness was more excellent. On the other hand, in Example 9 in which the thickness of the additional woven fabric exceeds 0.5 mm, marks by warps and wefts having a high fineness are observed, which confirms that the additional woven fabric having a thickness of 0.5 mm or less is preferable. .

  The papermaking felt of the present invention is used by being disposed inside a papermaking press belt, and is excellent in water squeezing, and can be used in various paper manufacturing processes in addition to paper with a large amount of squeezed water such as paperboard. .

  100, 200; felt for papermaking, 1; base fabric, 2; front bat layer, 21; front bat layer, 22; outer bat layer, 3; back bat layer, 4; additional woven fabric, 41, 42; Constituent yarn of woven fabric, 4a; fluff, 10; evaluation device, 51 and 52; press roll, 6; suction box, 7;

Claims (9)

With the base fabric,
A front bat layer laminated on the paper surface of the base fabric;
A papermaking felt comprising a back bat layer laminated on the running surface of the base fabric,
In the front bat layer, at least one layer of the resin detachment preventing woven fabric is disposed in the thickness direction of the front bat layer, and the scale of the resin detachment preventing woven fabric is 0.5-3. 0.0 mm,
A papermaking felt, wherein at least the front butt layer and the woven fabric for preventing resin dropping are resin-processed.   The outer bat layer has an inner bat layer laminated on the base fabric and an outer bat layer laminated on the inner bat layer. The papermaking felt according to claim 1, wherein the felt is interposed between a layer and the outer bat layer.   The outer bat layer has an inner bat layer laminated on the base fabric and an outer bat layer laminated on the inner bat layer. The papermaking felt according to claim 1, wherein the felt is disposed in the layer.   The papermaking felt according to claim 2 or 3, wherein the fineness of the fibers constituting the in-table batt layer is 27 to 100 dtex.   The papermaking felt according to any one of claims 1 to 4, wherein the resin used for the resin processing is a water-based resin. The thickness of the resin falling-off preventing fabric is 0.1 to 0.5 mm, and felt for papermaking according to any one of claims 1 to 5 weight per unit area is 10 to 100 g / ^{m 2} .   The papermaking felt according to any one of Claims 1 to 6, wherein the yarn constituting the resin drop-off preventing woven fabric has fluff on its surface.   8. The method according to claim 1, wherein at least one of the warp and the weft constituting the resin detachment preventing woven fabric is at least one of a spun yarn, a multifilament twisted yarn, and a multifilament non-twisted yarn. The papermaking felt described.   The papermaking felt according to any one of claims 1 to 8, wherein at least one of the warp and the weft constituting the resin detachment preventing woven fabric is at least one of a hydrophilic yarn and a hydrophilic processed yarn.

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