JP5571404B2 - Papermaking felt and manufacturing method thereof, papermaking belt and manufacturing method thereof - Google Patents

Description

  The present invention relates to a papermaking felt in which a bat fiber layer is integrated with a base fabric layer, a manufacturing method thereof, a papermaking belt, and a manufacturing method thereof.

  In the papermaking process, a papermaking felt whose main purpose is to squeeze the moisture of the wet paper while transporting the wet paper, and a papermaking belt whose main purpose is to transport the wet paper (both transport felt and transport belt) Called). Papermaking felts are configured to include at least a base fabric layer and a bat fiber layer, and generally used are breathable felts that have been subjected to chemical processing or resin processing. Also, the papermaking belt uses a non-breathable or slightly breathable belt having a structure in which the base fabric layer is processed with resin and a structure in which the base fabric layer and the bat fiber layer are processed with resin. Yes.

  In felts for papermaking, a bat fiber layer of the required thickness is laminated and integrated on the base fabric layer, but on its surface, relatively small irregularities due to the bat fiber itself, spots on the bat fiber, and the needling method There are various large and small irregularities, such as relatively large irregularities generated by. If the unevenness of the surface of the bat fiber layer is remarkable, the surface property of the wet paper pressed together with the felt by the press roll on the paper making machine will also deteriorate. In addition, it is known among felt manufacturers for papermaking that the surface property of felt has a great influence on the water squeezing ability. The larger the irregularity of the felt surface, the more uneven the pressure state under pressure by the press roll. As a result, the felt watering performance decreases. For this reason, it is required to improve the surface property, that is, to make the surface of the bat fiber layer smoother with less irregularities on the papermaking surface side.

  In general, surface roughness parameters such as arithmetic average roughness Ra defined in JIS B0601 are used for evaluation of surface properties, and these parameters may be applied to papermaking tools (for example, , See Patent Document 1). Patent Document 1 discloses a paper transport belt, and since the surface is a resin layer, the surface state does not change greatly even when pressed. However, in the felt for papermaking, the felt surface is an aggregate in which bat fibers, which are short fibers, are entangled with each other. When pressed, the bat fibers move and the aggregate state of the bat fibers on the felt surface changes. Therefore, the surface roughness parameters such as arithmetic mean roughness Ra, which is a measurement under non-pressurization, evaluate the surface properties of the felt under non-pressurization and use parameters such as pressure uniformity that are measured under pressure. It is preferable to do.

  In order to smooth the surface of the bat fiber layer, for example, a method using bat fibers having a small fineness is applied. Reducing the fineness of the bat fiber reduces the relatively small irregularities caused by the diameter of the bat fiber, and also increases the number of bat fibers when using the same weight of bat fiber, so it depends on the local fiber state The surface roughness to be reduced can be reduced. As another method for smoothing the surface of the bat fiber layer, a technique is disclosed in which a papermaking felt is pressed during finishing to form a flat surface. By pressing the felt for papermaking, the surface roughness and pressure uniformity can be reduced (see, for example, Patent Documents 2 to 5).

  However, it is not easy to reduce the pressure uniformity depending on the fiber spots and entanglement spots only by the method using bat fibers with small fineness. Depending on the stage of the papermaking process, papermaking felts require dehydration, dirt prevention, hair removal prevention, etc. in addition to surface properties. There is a possibility that a new problem such as facilitation may occur.

  On the other hand, in a papermaking belt, a surface on which a resin layer is exposed is formed on the side that is usually in contact with wet paper. This surface is formed by applying, impregnating, and curing a resin to the bat fibers located on the surface layer. Even on this resin exposed surface, smoothness of the surface is required for transporting wet paper. If the surface of the bat fiber before the resin is applied and impregnated is not smooth, the resin exposed surface will not be smooth, and papermaking It had the same problem as the felt.

  Therefore, a technique for smoothing the surface in contact with the wet paper by impregnating or applying a resin to the surface bat fiber layer to cure the surface layer and then polishing the surface layer is disclosed (for example, Patent Document 6). reference).

Japanese Patent No. 3264461 JP 2006-9188 A Japanese Patent No. 3360145 Special table 2007-532785 gazette Japanese Patent No. 2649044 Patent No. 4064930

  However, only the method of using vat fibers with a small fineness or the method of pressing a papermaking felt during finishing to form a flat surface smoothes the surface in contact with wet paper that depends on the fiber spots and tangles. Is not easy, and the hardened layer (surface treatment layer) formed on the surface layer is also affected by this, so the pressure state during pressurization in paper felt may be uneven and the paper surface property may be reduced. was there. On the other hand, even in the papermaking belt, the non-uniform pressure state during pressurization may deteriorate the wet paper transportability.

  Furthermore, if the surface of the papermaking felt or the papermaking belt is not smooth, the liquid resin and chemicals to be applied, impregnated and dispersed easily adhere to the surface, and the thickness of the surface treatment layer also becomes nonuniform. Non-uniform thickness causes problems such as reduced stain resistance and conformability in one wet paper, and non-uniform thickness between multiple wet papers also reduces water squeezing and impairs stable paper quality. There was a fear.

  The present invention has been devised based on such inventor's knowledge, and its main object is to provide a papermaking felt and a papermaking belt provided with a surface treatment layer having a uniform thickness, and a method for producing the same. There is to do.

In order to solve such problems, the present invention is a papermaking felt or papermaking belt comprising at least a base fabric layer and a surface layer in which bat fibers are entangled and integrated with the base fabric layer by needling. By polishing the surface of the paper layer, the coefficient of variation of the felt surface pressure distribution under an average pressure of 0.1 MPa is 0.25 or less, and the arithmetic average roughness Ra is in the range of 10 to 38 μm. And a surface treatment layer formed by applying, impregnating, or spraying a predetermined solution to the polished surface.

  According to the said structure, a surface layer can be smooth | blunted by using the felt with a small fineness, or pressing a felt by grind | polishing the surface layer in which the bat fiber was entangled. And a surface treatment layer with little thickness variation can be formed by applying, impregnating or spraying a predetermined solution of resin, chemicals, etc. on this smooth surface layer. Further, when the surface layer is polished, the batt fibers are polished, so that the fibers are flattened and fine scratches are generated on the fiber surface. Since this flattening and fine scratches make it easier for a predetermined solution to penetrate, a more uniform surface treatment layer thickness can be realized.

  The evaluation of the polished felt surface may use both the coefficient of variation of the surface pressure distribution that can evaluate the felt surface under pressure and the arithmetic average roughness that can evaluate the felt surface under non-pressure. Is preferred. According to the above configuration, the felt surface property in a state where the felt is used on the paper machine can be accurately evaluated by processing the felt surface in the above range using these two parameters in combination, and a desired surface. The state can be obtained.

  Here, the variation coefficient is obtained by calculating the standard deviation of the measured pressure distribution on the surface based on the definition of JISZ8101-1-1.15, and then dividing the standard deviation by the average value of the pressure. This coefficient of variation relatively represents variations in pressure distribution. The arithmetic average roughness is defined in JIS B 0601: 2001 “Product Geometrical Specification (GPS) —Surface Properties: Contour Curve Method—Terminology, Definition, and Surface Property Parameters”.

  The pressure at the time of measuring the pressure on the felt surface is optimally 0.1 MPa. The reason is as follows. That is, the pressure uniformity of the felt can be divided into pressure uniformity mainly caused by the base fabric layer and pressure uniformity caused by the surface bat layer (= surface pressure uniformity). In order to reduce pressure spots caused by the base fabric layer, it is necessary to change the base fabric design. However, if the base fabric design is changed, other performance changes besides pressure uniformity. It is difficult to improve only the pressure uniformity while maintaining the performance required for other felts. On the other hand, by performing surface polishing, the surface pressure uniformity can be improved while maintaining the performance required for other felts. And since the pressure spot resulting from a base fabric layer does not generate | occur | produce under the pressure of about 0.1 MPa (it is not measured), only a felt surface pressure uniformity can be evaluated by the pressure measurement of 0.1 MPa.

  In the papermaking felt having the above structure, the predetermined solution may be a chemical having a hydrophilic group or a resin in which a chemical having a hydrophilic group is mixed with a thermosetting resin. According to this configuration, the hydrophilicity of the surface layer is improved by applying, spraying, etc., a known externally added deposit control agent, which is a chemical having a hydrophilic group, to the polished and smooth surface layer, for example, Adhesion of deposits such as calcium carbonate generated in the process can be suppressed. Such a configuration can improve the conformability of the papermaking felt.

  In the papermaking felt or the papermaking belt having the above-described configuration, the predetermined solution may be a thermoplastic resin. According to this configuration, the surface property, dehydration property, antifouling property, hair loss prevention property, etc. required according to the papermaking process are appropriately controlled by applying and impregnating a thermoplastic resin that softens and melts by heat treatment. be able to. Moreover, the surface layer can be removed by heating the surface layer as necessary. The applicable resin is not particularly limited, but polyurethane, polycarbonate urethane, polyacrylate, polyethylene terephthalate, polyvinyl chloride, acrylic resin, and the like can be applied.

  In the papermaking felt or the papermaking belt having the above-described configuration, the predetermined solution may be a thermosetting resin. According to this configuration, the surface property, dehydration property, antifouling property, hair loss prevention property, etc. required according to the papermaking process can be applied by applying and impregnating a thermosetting resin whose properties do not change once cured. Can be appropriately controlled. In addition, although applicable resin is not restrict | limited in particular, A urethane resin, an epoxy resin, a phenol resin, etc. are applicable.

The present invention is a method for producing a papermaking felt or a papermaking belt comprising at least a base fabric layer and a surface layer in which bat fibers are entangled and integrated with the base fabric layer by needling, wherein the surface of the surface layer is formed. Polishing and forming a flat surface in which the variation coefficient of the felt surface pressure distribution under an average pressure of 0.1 MPa is 0.25 or less and the arithmetic average roughness Ra is in the range of 10 to 38 μm ; And a step of forming a surface treatment layer by applying, impregnating or spraying a predetermined solution.

  Thus, according to the present invention, by polishing the felt surface layer before resin processing or chemical processing, the permeability of the resin or chemical can be improved, and a more uniform surface treatment layer can be formed. A papermaking felt and a papermaking belt provided with a surface treatment layer having a uniform thickness and a method for producing the same can be provided. A surface treatment layer having a uniform thickness can suppress, for example, a decrease in water squeezing and can provide stable papermaking quality for a long period of time. Further, according to the present invention, it is possible to prevent the resin and chemicals from falling off when the polishing is performed after resin processing or chemical processing as in the prior art, so there is no waste and the increase in cost can be suppressed. Further, since the surface area is increased by polishing, the adhesiveness of the resin and chemicals is increased, and the dropout during use can be prevented, so that the durability of the surface treatment layer can be improved. As described above, the present invention contributes to improvement of productivity and also to cost reduction.

It is typical sectional drawing which shows an example of the papermaking felt concerning one Embodiment of this invention, and has shown the state before apply | coating, impregnating or spraying a predetermined | prescribed solution. It is typical sectional drawing which shows the comparative example concerning a prior art, and has shown the state before resin is impregnated. It is typical sectional drawing which shows an example of the felt for paper manufacture concerning one Embodiment of this invention, and has shown the state after apply | coating, impregnating or spraying a predetermined | prescribed solution. It is typical sectional drawing which shows the comparative example concerning a prior art, and has shown the state after being impregnated with resin. It is a typical side view which shows an example of the grinding | polishing process of the felt for paper manufacture concerning one Embodiment of this invention. It is explanatory drawing of surface roughness. It is a drawing substitute photograph which shows the measurement result of the pressure measurement film before the grinding process of the Example concerning one Embodiment of this invention. It is a drawing substitute photograph which shows the measurement result of the pressure measurement film after the grinding process of the Example concerning one Embodiment of this invention. It is a comparative example concerning a prior art, and is a drawing substitute photograph which shows the measurement result of the pressure measurement film at the time of carrying out resin processing on the surface layer of the papermaking felt. It is a comparative example concerning a prior art, and is a drawing substitute photograph which shows the measurement result of the pressure measurement film at the time of grinding | polishing the surface after carrying out resin processing to the surface layer of the felt for paper manufacture. It is a drawing substitute photograph which shows the measurement result of the pressure measurement film in the Example concerning one Embodiment of this invention.

  Hereinafter, an embodiment according to the present invention will be described with reference to the drawings. In the following, the papermaking felt will be described, but the present invention can be applied to a papermaking belt having a similar configuration.

  FIG. 1 is a schematic cross-sectional view showing an example of a papermaking felt according to an embodiment of the present invention. This felt 10 has a multi-layer structure in which a batt fiber layer 2 as a surface layer is laminated and integrated on a base fabric layer 1 by needling. The base fabric layer 1 can be a monofilament yarn or a fabric woven from a plurality of filaments twisted by a loom, but is not limited to this, and only a multilayer fabric, a width direction or a length direction yarn can be used. A formed cloth, a resin sheet, or the like can also be applied.

  The plane 3 opposite to the base fabric layer 1 of the batt fiber layer 2 is the side on which the wet paper (not shown) contacts. The surface of the plane 3 is polished so as to have a predetermined “arithmetic average roughness” and “coefficient of variation of surface pressure distribution” that do not cause “paper removal”.

  On the other hand, referring to the comparative example according to the prior art of FIG. 2, the comparative example also has a multilayer structure in which the batt fiber layer 12 is laminated and integrated on the base fabric layer 11 by needling. However, the surface 13 on the opposite side of the base fabric layer 11 of the bat fiber layer 12 is in a state in which the irregularities generated during the needling remain. Thus, when the unevenness | corrugation of the surface 13 is remarkable, the surface property of the wet paper pressed with a felt with a press roll on a papermaking machine will also fall. Further, the surface property of the felt has a great influence on the water squeezing ability, and the greater the unevenness of the felt surface, the more uneven the pressure state under pressure by the press roll, and the felt water squeezing performance decreases. Even when the papermaking felt is pressed during the finishing process to form a flat surface, the bat fibers of the bat fiber layer are intertwined in a complex manner, so there is local variation in hardness on the surface of the bat fiber layer. There was a portion having spotted spots, and this variation and spots reduced the surface properties of the wet paper.

  In this embodiment, the flat surface 3 shown in FIG. 1 is formed by polishing the batt fiber layer 12 up to the polishing line 14 shown by a broken line in FIG. In the present embodiment, since the surface polishing is performed after the needling step, the surface properties can be improved without being affected by the needling. Further, by polishing the felt, the bat fiber is polished to flatten the fiber, thereby causing fine scratches and burrs on the fiber surface. The flattening of the fiber and the formation of fine scratches and burrs increase the surface area of the fiber, so that a predetermined solution can easily penetrate.

  Referring to FIG. 3, the felt 10 has an adhesive, which is a predetermined solution, a chemical having a hydrophilic group (for example, a deposit control agent), and a thermosetting resin on a flat surface 3 formed by polishing the batt fiber layer 2. The surface treatment layer 4 is formed by applying, impregnating, or spraying a resin mixed with a chemical having a hydrophilic group, a resin (for example, a thermoplastic resin, a thermosetting resin), or the like. The predetermined solution penetrates into the batt fiber layer 2 from the surface 3 that has been polished to increase hydrophilicity, and also forms an impregnation layer 5. The surface 6 of the surface treatment layer 4 is formed in a state where the smoothness of the surface 3 of the batt fiber layer 2 is maintained.

  On the other hand, when the resin processing is performed in a state where the surface layer is not polished as shown in FIG. 2, the surface 23 of the surface treatment layer 24 is the surface of the bat fiber layer 12 as shown in FIG. Since it is formed in a state in which the 13 irregularities are maintained, large irregularities are generated. Further, the influence of the irregularities causes not only the surface treatment layer 24 but also the depth of the impregnation layer 25 to be non-uniform.

  FIG. 4B shows a state where the felt processed with resin in FIG. 4A is polished. If the surface irregularity of the bat fiber layer 12 is large as shown in FIG. 4A, the surface treatment layer 24 is also affected by the surface irregularity, and the polished surface 33 has a certain smoothness. However, the thickness of the surface treatment layer 24 becomes uneven, and the batt fiber layer 12 without the surface treatment layer 24 is exposed depending on the location. The non-uniformity in the thickness of the surface treatment layer 24 and the exposure of the batt fiber layer 12 cause local hardness variations, so that the pressure state during pressurization in the papermaking felt becomes nonuniform and the surface of the paper Had reduced sex.

  Next, an example of surface polishing will be described with reference to FIG. The felt 10 is formed in a loop shape with the bat fiber layer 12 (see FIG. 2) on the outside, and is spanned between a pair of transport rolls 21 and 21 installed at a predetermined interval so that a constant tension is applied. Yes. The transport rolls 21 and 21 rotate clockwise, and the felt 10 rotates clockwise. A polishing roll 22 is disposed between the transport rolls 21 and 21, and the polishing roll 22 is placed on the bat fiber layer 12 in FIG. 3 so as to contact the bat fiber layer 12 of the felt 10 (see FIG. 2) with a constant pressure. It is energizing upward.

  The polishing roll 22 is provided with a polishing cloth on the outer surface, and the width of the polishing roll is appropriately selected according to the width of the felt 10. The polishing process is not limited to the case where a polishing roll is used, and polishing paper, a polishing belt, a polishing plate, and the like can also be applied.

  The polishing roll 22 rotates in a clockwise direction in contact with the bat fiber layer 12. Since the felt 10 also rotates in the clockwise direction, the polishing cloth of the polishing roll 22 and the bat fiber layer 12 (see FIG. 2) abut against each other so that the bat fiber layer 12 is polished. In the configuration of FIG. 5, the surface 13 is polished to the polishing line 14 as shown in FIG. 2 by appropriately setting the pressure for energizing the batt fiber layer 2 and the polishing time, and the polishing is performed as shown in FIG. 1. A plane 3 is formed. In such a polishing process, the burr of the bat fiber generated by polishing is put in a state lying on a certain direction, so that the wet paper is felt by setting the traveling direction of the felt in the paper making process to a direction in which the burr is suppressed. It can be prevented from being caught and dragged by burrs on the surface layer.

  Here, with reference to FIG. 6, “surface roughness”, which is a surface state in which undulations of peaks and valleys continue at small intervals, will be briefly described. “Surface roughness” is defined as “arithmetic average roughness Ra” in JIS B 0601: 2001 “Product Geometric Specification (GPS) —Surface Properties: Contour Curve Method—Terminology, Definitions and Surface Properties Parameters”. .

  Fig.6 (a) is a schematic diagram of the cross-sectional curve of the surface 13 (refer FIG. 2) of the bat fiber layer 12 used as the measuring object measured by the surface roughness measuring device (not shown). FIG. 6A reproduces the surface properties shown in FIG. 2 as a cross-sectional curve.

  In FIG. 6A, when the horizontal axis is x and the vertical axis is z, the sectional curve is Z (x). The “arithmetic average roughness Ra” can be obtained by gradually integrating the Z (x) with the evaluation length L by the evaluation length L, and has a cross-sectional curve shown in FIG. In the examples described below, “arithmetic mean roughness Ra” in accordance with JIS B 0601: 2001 is shown.

  On the other hand, the variation coefficient of the surface pressure distribution is obtained by calculating the standard deviation of the measured surface pressure distribution based on the definition of JISZ8101-1-1.15, and then dividing this standard deviation by the average value of the pressure. . This coefficient of variation relatively represents variations in pressure distribution.

  The variation coefficient of the surface pressure distribution can be easily obtained by analyzing the pressure data measured by the pressure measurement film on the polished surface. For example, pressure spots are measured with a pressure measurement film (prescale for fine pressure (4LW) 0.05 MPa-0.2 MPa: manufactured by Fuji Film), and the measurement result is a pressure image analysis system (manufactured by Fuji Film: FPD-9210). It is possible to obtain a variation coefficient of pressure distribution by taking out the pressure data in each part using the export function and statistically processing this data with Microsoft Excel CEL.

  The pressure at the time of measuring the pressure on the felt surface is optimally 0.1 MPa. That is, the pressure uniformity of the felt can be divided into the pressure uniformity mainly due to the base fabric layer and the pressure uniformity due to the surface bat layer (= surface pressure uniformity). Since the pressure spots do not occur under the pressure of about 0.1 MPa (not measured), only the felt surface pressure uniformity can be evaluated by the pressure measurement of 0.1 MPa.

<Example of surface polishing>
Next, examples of surface polishing according to the present embodiment will be described. In this example, a base material layer formed by weaving warps and wefts with a loom is needling nylon bat fiber, which is a polyamide synthetic fiber as a surface layer. The fiber materials and finenesses of Examples 1-1 and 1-2 and Reference Examples 1-1 to 1-4 are shown in Table 1. Here, the fineness of Examples 1-1 and 1-2 is 17 dtex or more and 24 dtex or less. Reference Examples 1-1 and 1-2 are batt fiber layers having a fineness of 24 dtex or more, and Reference Examples 1-3 and 1-4 are batt fiber layers having a fineness of 17 dtex or less. In Example 1-2 and Reference Example 1-1, the batt fiber layer is formed of two types of fibers having different finenesses.

  In the example and the reference example, the surface shown in FIG. 1 is subjected to the polishing process shown in FIG. 5, and the “roughness” after the needling shown in FIG. 2 and the uneven pressure distribution remain. Is in a polished state. Table 2 shows the results of measurement of density, polishing amount, air permeability before and after polishing, and air permeability, which are the physical properties of the felt, in Examples and Reference Examples before and after polishing.

Referring to Table 2, there is no significant change in air permeability before and after polishing in both the examples and the reference examples. As described above, the polishing process in the present example and the reference example does not change the ventilation characteristics of the bat fibers themselves in the examples and the reference examples provided for the process. The density of Examples 1-1 and 1-2 and Reference Examples 1-1 to 1-4 is 0.390 g / cm ³ or more, and neither of them shows fuzz on the felt surface after polishing.

  Table 3 shows the difference (percentage) between the measured values of the surface pressure distribution variation coefficient before and after polishing and the measured values before and after polishing for the examples and reference examples. Table 4 shows the difference (percentage) between the measured value of arithmetic average roughness Ra before and after polishing and the measured value before and after polishing for the examples and reference examples.

  Referring to Table 3, the “variation coefficient of the surface pressure distribution” decreases in both the examples and the reference examples, that is, a more uniform pressure distribution than before the polishing process is realized. Referring to Examples 1-1 and 1-2 and Reference Examples 1-2, 1-3, and 1-4, the surface pressure distribution coefficient of variation (JISZ8101-1) was polished to be 0.25 or less. Yes. Thus, polishing can reduce the non-uniform pressure distribution on the felt surface. Further, the difference between the measured values before and after the polishing process expressed as a percentage is larger than that of the reference example, which indicates that the polishing process effect of reducing the non-uniform pressure distribution is high. However, even in the reference example, in Reference Examples 1-2, 1-3, and 1-4, the coefficient of variation of the pressure distribution is reduced by 15% or more due to polishing, and for example, Reference Example 1-2 is a 27 dtex bat Although the fineness is used, it is possible to obtain a surface pressure distribution superior to the pressure distribution before polishing of Example 1-1 using a 17 dtex bat by polishing, which is practically useful. From these facts, when felt is used, it is preferable to reduce the coefficient of variation of the surface pressure distribution by 15% or more by polishing, and further reduce it by 22% or more as in Examples 1-1 and 1-2. Is particularly preferred.

  Next, when the arithmetic average roughness Ra is viewed with reference to Table 4, it is included in the range of the arithmetic average roughness Ra of the polished surface of 10 to 38 μm in the example, and 10 in the reference examples 1-2 to 1-4. It is included in the range of ˜45 μm. The arithmetic average roughness Ra of the polished surface is preferably 10 to 45 μm or less in order to improve machine operation efficiency by improving felt water squeezing and also to improve the surface property of paper produced by a paper machine. More preferably, the thickness is 10 to 38 μm or less. As described above, according to the present invention, even in Reference Examples 1-2 to 1-4, an improvement in machine operation efficiency by improving felt water squeezing and an improvement in surface properties of paper produced by a paper machine are realized. I can do it.

  Moreover, when the difference of the measured value before and behind grinding | polishing process is seen, compared with a reference example, it turns out that the reduction | decrease of arithmetic average roughness before and behind grinding | polishing process is 25% or more and is very large. On the other hand, as in Reference Examples 1-3 and 1-4, when the fineness was small, the polishing workability was poor. In particular, in Reference Example 1-4, the effect of reducing the roughness by polishing was not obtained.

  The measurement results of the pressure measurement film before and after polishing in the examples are shown in FIGS. 7 and 8, respectively. The pressure measurement film develops a color at a pressurized portion. When the pressure is high, the color is deep, when the pressure is low, the color is thin. Comparing the surface texture of FIG. 7 before polishing and the surface texture of FIG. 8 after polishing, a lot of white and light portions are seen before polishing in FIG. It can be seen. On the other hand, after the polishing process of FIG. 8, although there are some light-colored portions, there is no white portion, and the entire color is seen almost uniformly, and no needling meridians are seen.

  According to the present embodiment, by polishing the felt surface layer, it is possible to improve the surface properties of the felt surface layer without using a felt having a small fineness or pressing the felt with an excessive pressure. Moreover, the felt concerning the said structure can improve the surface property of a felt surface layer, without impairing dehydrating property, stain | pollution | contamination prevention property, and hair loss prevention property by selecting suitably the batt fiber with which a surface layer is equipped. Further, polishing the felt causes the batt fibers to be polished to flatten the fibers, thereby causing fine scratches and burrs on the fiber surface. The flattening of the fiber and the formation of fine scratches and burrs increase the surface area of the fiber, so that a predetermined solution can easily penetrate.

<Example of surface treatment layer formation>
Next, an example of a surface treatment layer formed by applying, impregnating, or spraying a predetermined solution of resin, chemicals, etc. to the polished surface layer will be described with reference to the drawings. 9, 10, and 11 show the measurement results of the pressure measurement film corresponding to FIGS. 4 (a), 4 (b), and 3, respectively. As shown in FIG. 9, in the case of (no polishing, resin processing), the adhesion of the resin is not uniform, and the pressurized state is not uniform. In addition, transmuscles are also seen, and the difference in shade of color representing the magnitude of local pressure is also increasing. Next, as shown in FIG. 10, (no polishing, resin processing, polishing) is generally smooth by polishing, but there is a portion with a large shade of color, and a meridian also remains. On the other hand, in FIG. 11, the pressurized state is almost uniform, and the color density is small as a whole, and the meridians are not visible.

  From FIG. 4 (a) and FIG. 9, (without polishing, resin processing), the impregnation of the resin is non-uniform because the surface is rough, and the pressure is non-uniform because it is cured to maintain the rough surface state. It has become. From FIG. 4 (b) and FIG. 10, (no polishing, resin processing, polishing) shows that even when the polishing processing is performed, the resin is originally not uniformly impregnated, so the pressure state is non-uniform. . Further, when the amount of polishing is increased, a portion without the resin is exposed, so that the pressurization state may be further non-uniform. On the other hand, from FIG. 3 and FIG. 11, this example can maintain a smooth surface because the original surface is smooth and the resin impregnation is uniform.

  According to the present embodiment, by polishing the surface layer intertwined with the bat fibers, the surface layer can be smoothed without using a felt having a small fineness or pressing the felt. And a surface treatment layer with little thickness variation can be formed by applying, impregnating or spraying a predetermined solution of resin, chemicals, etc. on this smooth surface layer. Further, when the surface layer is polished, the batt fibers are polished, so that the fibers are flattened and fine scratches are generated on the fiber surface. Since this flattening and fine scratches make it easier for a predetermined solution to penetrate, a more uniform surface treatment layer thickness can be realized.

  The preferred embodiments of the present invention have been described above. The present invention is not limited to what is described in the specification and drawings, and design changes can be made without departing from the spirit of the invention. For example, a water-soluble polymer adhesive such as polyvinyl alcohol glue or starch glue may be applied to the surface fiber before polishing the batt fiber, and the adhesive may be removed after polishing. By such a procedure, the polishing process can be facilitated by fixing the surface layer. Furthermore, since the surface layer has already been smoothed by polishing, the thickness of the surface treatment layer (cured layer) can be reduced, resulting in productivity improvement and cost reduction.

  The felt for papermaking according to the present invention has an effect of improving the surface property of paper, and the felt for papermaking in which bat fiber layers are integrated on the surface or both front and back surfaces of a base fabric layer having a multilayer structure, In particular, it is useful as a press felt used in a press part (squeezing part) of a paper machine. The papermaking belt according to the present invention is useful for transporting wet paper in the papermaking process.

DESCRIPTION OF SYMBOLS 1,11 Base fabric layer 2,12 Butt fiber layer 3 Plane 4 Surface treatment layer 5 Impregnation layer 6 Surface 10 Felt 13 Surface 21 Transport roll 22 Polishing roll

Claims (5)

A papermaking felt or a papermaking belt comprising at least a base fabric layer and a surface layer in which batt fibers are entangled and integrated with the base fabric layer by needling,
By polishing the paper surface of the surface layer, the variation coefficient of the felt surface pressure distribution under an average pressure of 0.1 MPa is 0.25 or less, and the arithmetic average roughness Ra is in the range of 10 to 38 μm. and forming surface, the
A papermaking felt or a papermaking belt comprising a surface treatment layer formed by applying, impregnating or spraying a predetermined solution on the polished surface. The papermaking felt according to claim 1 , wherein the predetermined solution is a chemical having a hydrophilic group or a resin in which a chemical having a hydrophilic group is mixed with a thermosetting resin. The papermaking felt or papermaking belt according to claim 1 , wherein the predetermined solution is a thermoplastic resin. The papermaking felt or papermaking belt according to claim 1 , wherein the predetermined solution is a thermosetting resin. A method for producing a papermaking felt or papermaking belt comprising at least a base fabric layer and a surface layer in which batt fibers are entangled and integrated with the base fabric layer by needling,
The surface of the surface layer is polished to form a plane in which the variation coefficient of the felt surface pressure distribution under an average pressure of 0.1 MPa is 0.25 or less and the arithmetic average roughness Ra is in the range of 10 to 38 μm. Process,
And a step of forming a surface treatment layer by applying, impregnating or spraying a predetermined solution on the plane.