JP2006009207A - Felt for papermaking and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a felt for papermaking, of which substrate is constituted by a fabric of which MD directional yarns and CMD directional yarns consist of both only single yarns, also excellent in dimensional stability and hair removal resistance, and capable of suppressing an icicle phenomenon. <P>SOLUTION: This felt 10 for papermaking consists of a substrate 20 and a bat layer 30 made as one unit with the substrate 20, and the substrate 20 consists of the woven fabric of which MD directional yarns 22 and CMD directional yarns 24 are constituted by both single yarns. By heat-setting the substrate to impart crimps to the MD directional yarns 22, the felt for papermaking excellent in dimensional stability and hair removal resistance, and capable of suppressing the icicle phenomenon is obtained. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a papermaking felt used in a papermaking machine, and more particularly to a papermaking felt (hereinafter simply referred to as “felt”) having excellent dimensional stability.

The press part of the paper machine is composed of a pair of press rolls or a nip part composed of a press roll and a shoe, and the wet paper is pressurized in this nip part and squeezed from the wet paper.
And in the press part of such a paper machine, the papermaking felt for absorbing the water squeezed from the wet paper is used.

As shown in FIG. 2, the papermaking felt 1 is composed of a base body 2 and a bat layer 3 made of a bat fiber. The base body 2 and the bat layer 3 are intertwined and integrated by needle punching.
The substrate 2 is made of a woven fabric and is provided in order to develop the strength of the papermaking felt 1.
Conventionally, a twisted yarn is mainly used as the MD direction yarn 2A and / or the CMD direction yarn 2B of the woven fabric constituting the base body 2. Thus, by using a twisted yarn for the base 2 of the papermaking felt 1, it is possible to improve the sticking property of the bat fibers planted by the needle punch and the hair removal resistance of the felt. Further, the woven fabric constituting the base 2 is crimped only on the CMD direction yarn 2B, and the MD direction yarn 2A has a straight shape. Here, the crimp refers to the ups and downs of the CMD direction yarn 2B intersecting the MD direction yarn 2A having a straight shape.

  However, the disadvantage of using twisted yarns is that the woven fabric is bulky and the water permeability is lowered, resulting in poor water squeezing, and the higher the number of twists in the twisted yarn, the higher the tendency to stretch and the dimensional stability. It gets worse. In addition, since the untwisting property of the twisted yarn appears after weaving, there is a problem that slack may appear on the woven fabric surface during needle punching.

In contrast, various attempts have been made to improve dimensional stability.
Patent Document 1 discloses a sheet surface woven structure in which an MD direction yarn has an elastic modulus 10 to 40% lower than that of a CMD direction yarn, and a relative direction having an MD direction yarn and a CMD direction yarn woven on the opposite side. The two structures have a rough wear surface fabric structure and the two structures are integrated by interweaving the CMD direction yarn of the wear surface fabric structure with the MD direction yarn of the sheet surface fabric structure, thereby exhibiting a two-way crimp property A papermaking fabric is disclosed that has a surface and a mechanical surface that exhibits increased wear and stretch resistance.

  In Patent Document 2, by using a woven fabric having a warp double structure of 2/1 and 1/2 as a base, the binding force between the warp and the weft of the felt base is increased, and it is being used on a paper machine. It is disclosed that warp yarns can be prevented from jumping out on the felt surface (looping phenomenon).

Patent Document 3 discloses in paragraphs 0004, 0005, and 0024 that heat setting of a woven fabric imparts crimps to warps or wefts to improve dimensional stability. Here, heat setting is to fix the texture of the yarn by heat treatment, and has been conventionally performed to stabilize the form of a thermoplastic fiber product or the like.
JP 57-47996 A Japanese Patent Laid-Open No. 9-31881 Special table 2003-529686

However, none of these felts for papermaking of Patent Documents 1 to 3 are sufficiently satisfactory although the dimensional stability is improved to some extent.
On the other hand, if both the MD direction yarn and the CMD direction yarn are composed of only a single yarn, the woven fabric is not bulky, the water permeability is increased, the water squeezing property is improved, the elongation tendency is lowered, and the dimensional stability is improved. It has been.

  However, when both the MD direction yarn and the CMD direction yarn are composed of only a single yarn, the bat fibers that are needle punched and planted may not be firmly fixed, and the felt may have poor hair removal resistance. In particular, when both the MD direction yarn and the CMD direction yarn are composed of only a single yarn, the woven fabric composed of only the single yarn has a point contact at the intersection of the MD direction yarn and the CMD direction yarn. The binding force of the directional yarn is poor, and a warp phenomenon that the warp yarn jumps out from the felt surface in a loop shape occurs during use on a paper machine.

  In view of the above-mentioned problems, the present invention is configured such that the base is composed of a woven fabric in which both the MD direction yarn and the CMD direction yarn are composed of only a single yarn, and is excellent in dimensional stability and hair removal resistance, and suppresses the wiggle phenomenon. An object of the present invention is to provide a felt for papermaking.

  The present invention relates to a papermaking felt comprising a base and a bat layer integrated with the base, wherein the base is made of a woven fabric in which both the MD direction yarn and the CMD direction yarn are composed of only a single yarn, The above-mentioned problems have been solved by a papermaking felt characterized in that the MD direction yarn is crimped by heat-setting the substrate.

  According to the present invention, the substrate is composed of a woven fabric in which both the MD direction yarn and the CMD direction yarn are composed of a single yarn, and the substrate is heat-set to impart crimps to the MD direction yarn. It is possible to provide a papermaking felt that is excellent in depilation and can suppress the wiggling phenomenon.

The present invention will be described with reference to FIG.
The papermaking felt 10 of the present invention comprises a base 20 and a bat layer 30 integrated with the base 20, and the base 20 is a woven fabric in which both the MD direction yarns 22 and the CMD direction yarns 24 are composed of only a single yarn. Consists of. The base 20 is heat set, and the MD direction yarn 22 is crimped.
As described above, the base body 20 is composed of a woven fabric in which both the MD direction yarn 22 and the CMD direction yarn 24 are composed of a single yarn, and the base body 20 is heat-set and the MD direction yarn 22 is crimped. A papermaking felt that is excellent in stability and hair removal resistance and can suppress the wiggle phenomenon is obtained.

The crimp applied to the MD direction yarn 22 preferably has a pitch p of 5.0 mm or less and a height h0.10 mm or more. On the other hand, when the pitch p was larger than 5.0 mm and the height h was less than 0.10, occurrence of a wiggle phenomenon was observed.
Moreover, it is preferable that MD direction thread | yarn 22 is 500-2200 dtex, and CMD direction thread | yarn 24 is 800-2400 dtex.
Furthermore, it is preferable that the base body 20 is a bag weave woven so as to be seamless in the loom. Here, since the bag weave is well known to those skilled in the art, description thereof is omitted.

The heat setting of the substrate 20 is preferably performed under tension adjusted to 0.5 ton / m or less while the substrate is wound around a pair of rolls.
Actually, when the woven fabric was heat-set by a heat source from inside and / or outside of the roll while adjusting the roll gap under a constant tension of 1 ton / m, the MD direction yarn was not crimped and straight yarn It remained in shape.

Examples of the present invention will be described below.
MD direction yarn 800-1000 dtex nylon 6 single yarn CMD direction yarn 1000-1200 dtex nylon 6 single yarn Woven cloth 3/1 1/3 warp double bag weave The above woven cloth is hung on a pair of rolls, 0.2 While adjusting the roll gap so as to be under a constant tension of ton / m, heat setting the woven fabric by a heat source from inside and / or outside of the roll, the pitch of the MD direction thread is 2.4 mm, the height is 0.12 mm A crimp of
Furthermore, this woven fabric was put on a needle punch machine, and batt fibers were planted by needle punching to produce a papermaking felt.
When this papermaking felt was used in a papermaking machine, it was confirmed that there was no elongation or hair loss and no wiggle phenomenon occurred.

  As described above, according to the present invention, the base is composed of a woven fabric in which both the MD direction yarn and the CMD direction yarn are composed of a single yarn, and the base is heat-set to impart a crimp to the MD direction yarn. By this, it is possible to provide a papermaking felt that is excellent in dimensional stability and hair removal resistance and that can suppress the wiggle phenomenon.

The MD direction sectional drawing of the felt for papermaking of this invention. MD sectional drawing of the conventional felt for papermaking.

Explanation of symbols

10: Felt for papermaking 20: Substrate 22: MD direction thread 24: CMD direction thread 30: Butt layer

Claims (5)

In a papermaking felt comprising a substrate and a bat layer integrated with the substrate,
The base is made of a woven fabric in which both MD direction yarns and CMD direction yarns are composed of only a single yarn, and the MD direction yarns are crimped by heat-setting the base.
Papermaking felt.   The papermaking felt according to claim 1, wherein the crimp applied to the MD direction yarn has a pitch of 5.0 mm or less and a height of 0.10 mm or more.   The papermaking felt according to claim 1 or 2, wherein the substrate is a bag-woven fabric.   The papermaking felt according to any one of claims 1 to 3, wherein the MD direction yarn of the base is 500 to 2200 dtex and the CMD direction yarn is 800 to 2400 dtex. A base material and a bat layer integrated with the base material. The base material is made of a woven fabric in which both MD direction yarns and CMD direction yarns are composed of a single yarn. A method for producing a felt for papermaking in which a crimp is applied to an MD direction yarn,
The base is hung on a pair of rolls, heat set under a tension adjusted to 0.5 ton / m or less, and crimps are imparted to the MD direction yarn,
A method for producing felt for papermaking.

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