JP7053416B2 - Paper felt - Google Patents

Description

The present disclosure relates to a papermaking felt in which the base fabric has a woven fabric layer and a thread row layer.

Paper felt is used in the press part of paper machines to carry wet paper that is squeezed. The felt has a base cloth and a butt fiber layer formed by needle punching a short fiber sheet into the base cloth. As the base fabric, a woven fabric layer in which warp and weft are woven together and a layer in which a plurality of yarns extending in parallel directions are fixed to each other may be laminated. When both layers are connected to each other by entwining the short fibers of the butt fiber layer, the short fibers of the butt fiber layer on the running surface side are lost with use, so that the effect of connecting the two layers by the short fibers is reduced. Therefore, there may be a gap between the two layers.

In Patent Document 1, a first layer in which warp (MD yarn) and weft (CMD yarn) are plain-woven, and a second layer in which the warp (MD yarn) is arranged on the running surface side of the first layer and consists of only warp (MD yarn). A papermaking felt having a base fabric laminated with layers is described. In this felt for papermaking, the weft of the first layer and the warp of the second layer include a low melting point yarn, and both yarns are bonded to each other by heat melting, so that the first layer and the second layer are in contact with each other. The knot is strengthened.

Japanese Unexamined Patent Publication No. 2008-63673

In Patent Document 1, since the wefts of the first layer and the warp threads of the second layer are bonded only at the intersections, the adhesiveness is insufficient. Further, in Patent Document 1, since the yarn itself is thermally melted, the strength of the yarn (strength of the base fabric) is insufficient. Therefore, it is desired to further strengthen the mutual connection between the woven fabric layer and the layer made of threads parallel to each other. However, simply increasing the bonding area between the two layers increases the bending rigidity of the base fabric and hangs it. There is a risk that the insertability (easiness of attaching the felt to the paper machine) will decrease, and that the porosity will decrease and the air permeability will decrease. INDUSTRIAL APPLICABILITY The present invention reduces the strength of yarn while suppressing the deterioration of insertability and breathability in a papermaking felt having a base fabric in which a woven fabric layer and a thread row layer composed of threads parallel to each other are laminated. The purpose is to improve the adhesiveness between the woven fabric layer and the thread row layer to each other.

At least some embodiments of the present invention are a papermaking felt (10) having a base fabric (11) and a butt fiber layer (12, 13) laminated on the base fabric so that short fibers are entwined. The base fabric has a first yarn (14) constituting one of the warp and the weft, and a second yarn (15) constituting the other of the warp and the weft and woven into the first yarn. A fiber row layer having a cloth layer (16) and a third thread (17) arranged substantially parallel to the second thread, laminated on the woven cloth layer and bonded by an adhesive portion (19). The bonded portion is heat-melted after being processed with respect to the second yarn and / or the third yarn, or the woven fabric layer and / or the thread row layer. The second yarn contains a low melting point resin having a lower melting point than the first to third yarns, and the second yarn passes through the fiber row layer side of the three first yarns and then one first yarn. It is characterized in that it is woven into the first yarn in a repeating unit that passes through the side opposite to the yarn row layer of the above. Here, the term "substantially parallel" with respect to the second yarn includes the case where the third yarn is slightly inclined for the convenience of manufacturing. For example, when the thread row layer is formed by winding a plurality of third threads into a bundle in a spiral shape, a plurality of third threads are formed with respect to the second thread and the circumference of the base fabric. Although it is inclined by the width of the third thread, it is included in "substantially parallel" in such a case.

According to this configuration, the portion of the second yarn that passes through the thread row layer side with respect to the first yarn adheres to the third yarn, and this adhesive crimp is repeated at the length of three first yarns. Therefore, the length is not too long, so that the deterioration of the insertability and the breathability is suppressed, and the length is not too short, so that the woven fabric layer and the thread row layer adhere to each other. Is improving. Further, since the low melting point resin processed into the yarn serves as the adhesive portion of the adhesive portion, the strength of the yarn does not decrease as compared with the yarn containing the low melting point resin in the yarn itself.

At least some embodiments of the present invention are characterized in that, in the above configuration, the thread row layer is arranged on the papermaking surface side of the woven fabric layer.

According to this configuration, since the thread row layer having less unevenness than the woven fabric layer is arranged on the papermaking surface side, the surface of the papermaking felt on the papermaking surface side becomes smooth, and marks are placed on the manufactured paper. It is hard to stick and the paper surface is improved.

According to the present invention, in a felt for papermaking having a base fabric in which a woven fabric layer and a thread row layer are laminated, the strength of the yarn is not reduced while suppressing the deterioration of the insertability and the air permeability. It is possible to improve the mutual adhesion between the woven fabric layer and the thread row layer.

Schematic cross-sectional view of felt for papermaking

Hereinafter, embodiments according to the present invention will be described with reference to the drawings. FIG. 1 is a schematic cross-sectional view of a papermaking felt (hereinafter referred to as “felt”) 10 according to an embodiment.

The felt 10 includes a base cloth 11, a papermaking surface side butt fiber layer 12 laminated on the papermaking surface side of the base cloth 11, and a running surface side butt fiber layer 13 laminated on the running surface side of the base cloth 11. ..

The base fabric 11 has a woven fabric layer 16 having a first yarn 14 which is a weft and a second yarn 15 which is a warp woven into the first yarn 14, and a third yarn 17 which is substantially parallel to the second yarn 15. It has a thread row layer 18 laminated on the papermaking surface side of the woven fabric layer 16. Since the thread row layer 18 is formed by spirally winding a plurality of third threads 17 arranged in parallel with each other in a bundle, the third thread 17 is slightly smaller than the second thread 15. It is tilted. The third thread 17 may not be tilted with respect to the second thread 15 at all. For example, by cutting the thread row layer 18 composed of the third thread 17 inclined with respect to the second thread 15 and rearranging and joining them without inclining, the third thread 17 is joined with respect to the second thread 15. It can be arranged so that it does not tilt at all. Further, in the thread row layer 18, after winding (winding) the third yarn 17 between two rolls, a thin layer of butt fibers having a low melting point fiber is thermally melted and integrated with the third yarn 17. It is formed by. Therefore, the thread row layer 18 has a thin layer of butt fibers on one side. The thin layer of the butt fiber is hardly melted at the final product stage and does not remain in the fiber form.

The structure of the woven fabric layer 16 is a 3/4 kudzu, and the second thread 15 passes through the paper-making surface side of the three first threads 14 and then passes through the running surface side of one first thread 14. It is woven into the first yarn 14 in a repeating unit of doing. That is, the thread row layer 18 is laminated on the surface of the woven fabric layer 16 through which the second yarn 15 passes through one side of three continuous first yarns 14.

An adhesive portion 19 for adhering the two to each other is formed between the woven fabric layer 16 and the thread row layer 18. The adhesive portion 19 is formed between a portion of the second yarn 15 that passes through the paper-making surface side of the continuous first yarn 14 (adhesive crimp) and a third yarn 17 that overlaps this portion substantially in parallel. .. The adhesive portion 19 is formed by processing a low melting point resin having a melting point lower than that of the first to third threads 14, 15 and 17 with respect to the second thread 15 and / or the third thread 17 and thermally melting the resin. Will be done. The melting point of the low melting point resin processed by the resin is 130 to 170 ° C., and by applying heat at a temperature of 130 to 180 ° C. that does not melt the thread itself, only the low melting point resin is melted to form the adhesive portion 19. The woven fabric layer 16 and / or the thread row layer 18 may be formed after the second yarn 15 and / or the third yarn 17 is resin-processed in advance, and the woven fabric layer 16 and / or the yarn row may be formed. After forming the layer 18, the woven fabric layer 16 and / or the yarn row layer 18 may be resin-processed. In the step of performing thermal melting for adhering the woven fabric layer 16 and the thread row layer 18 to each other, a short fiber sheet made of synthetic fibers such as nylon is needle punched into the base fabric 11 and the butt fiber layer 12 on the papermaking surface side. And, it is preferable to perform it before the step of forming the running surface side butt fiber layer 13, but it may be performed afterwards.

Examples of the material of the first yarn 14 and the second yarn 15 constituting the woven fabric layer 16 include various materials such as polyamide and polyester, but polyamide is preferable in terms of flexibility and compression recovery. As the form of the first yarn 14 and the second yarn 15, a monofilament single yarn or a twisted yarn can be used, but the monofilament single yarn is preferable because of the adhesive surface that widens the adhesive portion. The thickness of the first yarn 14 and the second yarn 15 is preferably 0.10 to 0.60 mm, and particularly preferably 0.20 to 0.50 mm. Further, examples of the material and form of the third yarn 17 constituting the thread row layer 18 include polyamide, polyester, and natural materials, and examples of the form include twisted yarn of monofilament yarn and spun yarn, or multifilament yarn. Twisted yarn of spun yarn is preferable, and twisted yarn of polyamide monofilament yarn and spun yarn is particularly preferable. The thickness of the third thread 17 is preferably 0.50 to 1.50 mm, and particularly preferably 0.70 to 1.30 mm. Further, the melting points of the first yarn 14, the second yarn 15, and the third yarn 17 are 200 to 270 ° C. In order to enhance the adhesiveness between the second thread 15 and the third thread 17, the thickness of the third thread 17 is preferably different from that of the second thread 15, and the third thread 17 is 2 more than the second thread 15. It is more preferable that it is ~ 4 times thicker.

Since the second thread 15 to be bonded to the third thread 17 is substantially parallel to the third thread 17, the bonding area is larger and the adhesiveness is improved as compared with the case where the threads orthogonal to each other are bonded to each other. Further, if the adhesive crimp is short, the adhesiveness is lowered. On the other hand, when the adhesive crimp is long, the bending rigidity is high and the insertability is lowered, and the porosity is lowered and the air permeability is lowered. By setting the adhesive crimp to the width of the first thread 14 for three threads, the balance between the adhesiveness, the insertability and the breathability is optimized. Further, since the low melting point resin constituting the adhesive portion 19 is not contained in the second thread 15 and / or the third thread 17 itself, even if the low melting point resin is thermally melted, the thickness of the thread ( The form) and physical properties can be maintained, and the strength of the second thread 15 and / or the third thread 17 does not decrease. Further, since the thread row layer 18 having less unevenness is arranged on the papermaking surface side of the base cloth 11, the surface of the felt 10 on the papermaking surface side becomes smooth, and it is difficult for marks to be attached to the manufactured paper and the paper surface is good.

The structure of the woven fabric layer is plain weave (crimp for one first thread), 3/1 kudzu (corresponding to the embodiment of the present invention, crimp for three first threads), 5/1 kuzushi (second thread). A structure that passes through the paper-making surface side of five first yarns and then passes through the running surface side of one first yarn. The crimp for five first yarns) has the maximum peel strength and breathability. , And bending rigidity were measured.

As the first yarn (warp and weft) of the woven fabric layer, a monofilament of 6 nylon fibers having a diameter of 0.25 mm was used. As the second yarn (warp) of the woven fabric layer, a twisted yarn (0.40 mm in diameter) obtained by twisting two 6-10 nylon fibers having a diameter of 0.20 mm was used. As the third yarn (warp) of the thread row layer, three twisted yarns obtained by twisting two 6 nylon fibers having a diameter of 0.21 mm and one spun yarn twisted together (1.00 mm in diameter) were used. .. The sample was prepared by spraying a resin solution on the thread row layer, heating it with a dryer, superimposing the woven fabric layer and the thread row layer on each other without applying pressure, and heating with a heat press machine. ..

For maximum peel strength, 4 samples were measured for each tissue. In the measurement, both layers were pulled in the warp direction so as to split between the woven fabric layer and the thread row layer, and the force when both layers were peeled off was taken as the maximum peel strength. For air permeability, three samples were measured by changing the amount of the low melting point resin to be the adhesive portion. For comparison, the measurement was also performed when the amount of the low melting point resin was 0. The flexural rigidity was measured once for each of the square samples having a side of 10 cm by changing the amount of the low melting point resin as the adhesive portion, and also measured when the amount of the low melting point resin was 0 for comparison. ..

Table 1 shows the measurement results of the maximum peel strength. The maximum peel strength of the 3/1 kudzu structure is increased by 0.22N on average compared to the plain weave structure, and the maximum peel strength of the 5/1 kuzushi structure is higher than that of the 3/1 kuzushi structure. It increased by 0.09N on average. Even if the crimp length was changed from 3 first threads to 5 threads, the maximum peel strength did not increase as much as when the crimp length was changed from 1 thread to 3 threads.

Table 2 shows the measurement results of air permeability. When the second yarn of the woven fabric layer and the third yarn of the thread row layer are not adhered to each other without using a low melting point resin, there is a large difference in air permeability between the plain weave 3/1 kudzu and 5/1 kudzu structures. There was no. When the second yarn of the woven fabric layer and the third yarn of the thread row layer are adhered to each other, the texture of 5/1 kudzu is higher than that of plain weave or 3/1 kudzu regardless of the amount of resin. The decrease in breathability was extremely large.

Table 3 shows the measurement results of flexural rigidity. The flexural rigidity is low, and the softer the better, the easier it is to insert. The flexural rigidity increased as the length of the crimp increased, and increased as the amount of the low melting point resin increased. When the low melting point resin was 100 g / m ² , the bending rigidity increased sharply at the point where the low melting point resin changed from 3/1 kudzu to 5/1 kudzu.

Although the description of the specific embodiment is completed above, the present invention can be widely modified without being limited to the above embodiment. The first yarn may be a warp, the second yarn may be a weft, and the third yarn may be arranged along the substantially weft direction. Further, the base fabric layer may be arranged on the paper making surface side, and the thread row layer may be arranged on the traveling surface side. In this case, the second yarn is after passing through the traveling surface side of the three first yarns. It is woven into the first yarn in a repeating unit that passes through the paper-making surface side of one first yarn.

10: Paper-making felt 11: Base cloth 12: Paper-making surface side butt fiber layer 13: Running surface side butt fiber layer 14: First thread 15: Second thread 16: Woven cloth layer 17: Third thread 18: Thread row Layer 19: Adhesive part

Claims (2)

A papermaking felt having a base fabric and a butt fiber layer laminated on the base fabric so that staple fibers are entwined.
The base fabric includes a woven fabric layer having a first yarn constituting one of the warp and weft, and a second yarn constituting the other of the warp and weft and woven into the first yarn, and the second yarn. It has a third yarn arranged substantially parallel to the woven fabric layer, and has a yarn row layer laminated on the woven fabric layer and adhered by an adhesive portion.
The adhesive portion is formed from the first to third yarns that have been processed with respect to the second yarn and / or the third yarn, or the woven fabric layer and / or the thread row layer, and then melted by heat. Also contains a low melting point resin with a low melting point,
The second yarn is a repeating unit that passes through the thread row layer side of the three first yarns and then passes through the side opposite to the thread row layer of the first yarn. Felt for paper making, which is characterized by being woven into one thread. The felt for papermaking according to claim 1, wherein the thread row layer is arranged on the papermaking surface side of the woven fabric layer.

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