JP2020014747A - Nonwoven fabric wiper and manufacturing method of the same - Google Patents

Abstract

To provide a composite type nonwoven fabric wiper preventing pulp fibers from falling off, and improved in strength.SOLUTION: A composite type nonwoven fabric wiper WP is obtained by laminating a pulp fiber web PFW on a spunbond nonwoven fabric SW followed by integrating. The spunbond nonwoven fabric has a rate of elongation of 5% or less in a lateral direction CD when making a load of 0.5 N act in the lateral direction CD perpendicular to a fiber flow direction MD.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a composite type nonwoven fabric wiper obtained by hydroentangling a pulp fiber web and a spunbonded nonwoven fabric, and a method for producing the same.

  A composite nonwoven wiper including a pulp fiber web and a spunbonded nonwoven fabric is a wiper having both a liquid absorbing property based on pulp fibers and a strength based on a spunbonded nonwoven fabric. Also, it is widely used in various applications as a personal wiper such as a towel or a towel.

  For example, as disclosed in Patent Document 1, it can be obtained by laminating a pulp fiber web and a spunbonded nonwoven fabric, and then spraying a high-pressure water jet (water flow) to perform a hydroentanglement treatment to bind the fibers. . Here, the spunbonded nonwoven fabric has excellent strength, and thus functions as a backing layer of the manufactured composite nonwoven fabric wiper. On the other hand, the pulp fiber web has an excellent liquid absorbing function. Therefore, such a composite nonwoven fabric wiper is excellent in that it has both the advantages of a pulp fiber web having good absorbency for both aqueous and oily liquids and a spunbond nonwoven fabric having excellent strength. It can be provided to consumers as a nonwoven wiper.

Japanese Patent No. 2533260

  As for the spunbonded nonwoven fabric (referred to as a nonwoven continuous filament support in Patent Literature 1) used in Patent Document 1 and the like, those obtained by spunbonding a synthetic resin such as polypropylene are widely used. Has been adopted. In the spun bond processing, the spun resin fibers are connected to each other at a plurality of points by a point-like fusion part (hereinafter, referred to as a fusion point) to develop the sheet strength of the nonwoven fabric.

  However, the resin fibers (filaments) spun by the spunbonding process are aligned along the flow direction of the fibers during manufacturing (hereinafter, referred to as the longitudinal direction MD). The spunbonded nonwoven fabric connected at the fusion point as described above has a difference in elongation between the machine direction MD and the width direction perpendicular to the machine direction (hereinafter, referred to as the transverse direction CD). Specifically, a conventionally general spunbonded nonwoven fabric has a low elongation in the machine direction MD and a high strength. On the other hand, in the lateral CD, the elongation is large and the strength is low. Therefore, when the same external force was applied to the spunbonded nonwoven fabric, the elongation in the lateral direction CD was larger than that in the longitudinal direction MD.

Here, looking at the fiber state of the pulp fiber web placed on the spunbonded nonwoven fabric, the fibers are shorter and weaker than the spunbonded nonwoven fabric, and the difference in the elongation percentage between the machine direction MD and the transverse direction CD is small. .
As described above, in a composite nonwoven fabric wiper in which two types of fiber webs having significantly different physical properties are laminated and integrally manufactured, a pulp fiber is formed in a wiper sheet which is a finished product due to a difference in elongation. May easily fall off, or the strength may be reduced due to an imbalance in the vertical and horizontal strengths.

  Therefore, an object of the present invention is to provide a composite nonwoven fabric wiper in which the pulp fibers are prevented from falling off and the strength is improved by suppressing the difference in physical properties between the spunbonded nonwoven fabric and the pulp fiber web. is there.

  The above object is a composite type nonwoven fabric wiper in which a pulp fiber web is laminated and integrated on a spunbonded nonwoven fabric, wherein the spunbonded nonwoven fabric has a load of 0.5 N in a transverse direction perpendicular to the fiber flow direction. The nonwoven fabric wiper is characterized in that the elongation percentage in the lateral direction when acting on the nonwoven fabric is 5% or less.

  The elongation of the spunbonded nonwoven fabric is adjusted based on the arrangement density and / or shape in the lateral direction of the fusion points connecting the resin fibers constituting the spunbonded nonwoven fabric to each other. You can be.

Further, the area ratio of the fusion point is preferably 5 to 20%.
The fiber diameter of the spunbonded nonwoven fabric is preferably 0.6 to 5.6 dtex.

  The spunbonded nonwoven fabric / pulp fiber web, which is the weight composition ratio of the spunbonded nonwoven fabric and the pulp fiber web, is preferably 50/50 to 10/90 (wt%).

  The above object is a method for producing the nonwoven fabric wiper according to any one of the above, comprising at least a hydroentanglement step of hydroentanglement processing the spunbond nonwoven fabric and the pulp fiber web, The hole diameter φ of the water jet nozzle for injecting water is 0.06 to 0.15 mm, and the interval between the water jet nozzles is 0.4 to 1.0 mm. Can be achieved.

  ADVANTAGE OF THE INVENTION According to this invention, by suppressing the difference in the physical property of a spunbonded nonwoven fabric and a pulp fiber web, the fall of a pulp fiber is suppressed and the composite-type nonwoven fabric wiper which improved the strength can be provided.

It is the figure which expanded typically in order to explain the state of the fusion point in the spunbonded nonwoven fabric used for the compound type nonwoven fabric wiper concerning the present invention, and (a) shows the conventional spunbonded nonwoven fabric for comparison. FIG. 4B is a diagram showing a state of the arrangement of fusion points, FIG. 4B is a diagram showing a state of a fusion point in a spunbonded nonwoven fabric as a preferred example, and FIG. FIG. 4 is a view showing a state of arrangement of fusion points in a bonded nonwoven fabric. It is the figure which showed about the composite type nonwoven fabric wiper manufacturing apparatus which concerns on this invention.

Hereinafter, a composite nonwoven fabric wiper according to an embodiment of the present invention will be described with reference to the drawings.
The wiper according to the present invention is a composite nonwoven fabric wiper obtained by laminating a pulp fiber web on a spunbonded nonwoven fabric and integrating them. Here, the adopted spunbonded nonwoven fabric has a characteristic configuration. Therefore, the configuration at that point will be described first with reference to FIG.

FIG. 1A is a schematic diagram showing a state of a fusion point MP of the conventional spunbonded nonwoven fabric SW shown for comparison, and the fusion point MP is arranged substantially uniformly over the entire surface of the spunbonded nonwoven fabric. Have been. The fusion point MP was obtained by melting and solidifying fibers with a known heating device designed to locally heat a very narrow range of long continuous resin fibers (filaments) constituting the spunbonded nonwoven fabric. Connection point, which provides strength as a spunbonded nonwoven fabric and maintains its outer shape.
It should be noted that the spunbond fiber immediately after being spun has manufacturing-derived properties such as a small elongation in the machine direction MD and a high strength, whereas a large elongation and a low strength in the cross direction CD. Here, conventionally, as shown in FIG. 1A, a spunbonded nonwoven fabric was obtained by similarly arranging the fusion points MP in the vertical and horizontal directions. Therefore, the obtained spunbonded nonwoven fabric is a nonwoven fabric having a difference in the elongation percentage in the vertical and horizontal directions in which the properties derived from production are directly reflected.

The present inventor has designed a composite nonwoven fabric wiper using a spunbonded nonwoven fabric SW in which the difference in elongation in the vertical and horizontal directions is kept low in view of the above problems. Specifically, as shown in FIG. 1B, the elongation rate in the lateral direction CD was suppressed by increasing the arrangement density of the fusion points MP-1 in the lateral direction CD perpendicular to the longitudinal direction MD. Spunbond nonwoven fabric SW. By reducing the distance between the adjacent fusion points MP-1 in the lateral direction CD, it is possible to obtain a spunbond nonwoven fabric SW in which the elongation rate in the lateral direction CD is suppressed as compared with the related art.
Further, as shown in FIG. 1 (c), the shape of the fusion point MP-2 to be formed is a shape elongated horizontally (horizontally long shape). Compared to a conventional simple circular shape, if the shape is horizontally long, more fibers are fused and a spunbonded nonwoven fabric SW having a reduced elongation in the horizontal direction can be obtained.

FIG. 1B and FIG. 1C show only one example of the fusion point MP to be formed. The round fusion point MP and the horizontally long fusion point MP may be combined. In short, either one or both of increasing the arrangement density of the fusion points MP in the lateral direction CD and making the fusion points MP elongated in the lateral direction, or both, are appropriately used for the spun bonding. What is necessary is just to adjust so that the elongation rate of the nonwoven fabric in the cross direction CD may be suppressed.
Specifically, in the spunbonded nonwoven fabric used in the composite nonwoven fabric wiper of the present invention, the elongation in the transverse direction at low load (0.5 N) is 5% or less, more preferably 2% or less. Thus, the arrangement density of the fusion point MP-1 and the horizontal shape of the fusion point MP-2 are set.
The elongation in the longitudinal direction of a conventional general spunbonded nonwoven fabric is about 2%. Therefore, by adjusting the elongation in the transverse direction to 5% or less, more preferably 2% or less, a spunbonded nonwoven fabric having the above-mentioned points improved can be obtained.

And when the existence ratio of the fusion point per unit area in the spunbonded nonwoven fabric, that is, the area ratio of the fusion point is set to 5 to 20%, more preferably 5 to 18%, the elongation rate in the transverse direction is more reliably achieved. Can be set to 5% or less.
As for the resin fiber constituting the spunbonded nonwoven fabric, it is preferable to use a resin fiber having a fiber diameter of 0.6 to 5.6 dtex.

In the composite nonwoven fabric wiper of the present invention, a pulp fiber web is laminated and integrated on a spunbonded nonwoven fabric satisfying the above conditions. The weight ratio of the spunbonded nonwoven fabric to the pulp fiber web (spunbonded nonwoven fabric / pulp fiber web) is preferably 50/50 to 10/90 (wt%).
Since the composite type nonwoven fabric wiper that satisfies the above conditions is designed so that the difference in elongation in the vertical and horizontal directions is small, pulp fibers can be prevented from falling off when used in wiping work, etc., and as a nonwoven fabric wiper Can be provided as a product having excellent strength.
In the composite nonwoven fabric wiper according to the present invention, for example, it is preferable to form a pulp fiber web using pulp having an average pulp fiber length of 1.0 to 5.0 mm. Specifically, it is preferred that the pulp fiber web be formed using fibers of softwood bleached kraft pulp (NBKP) selected from the group consisting of radiata pine, slash pine, southern pine, lodgepole pine, spruce and Douglas fir. . A pulp fiber web made of any one pulp fiber may be used, or a pulp fiber web formed by mixing two or more pulp fibers.
The synthetic fibers constituting the spunbonded nonwoven fabric can be selected from nylon, vinylon, polyester, acryl, polyethylene, polypropylene, polystyrene and the like, and it is preferable to use polypropylene.

Hereinafter, a manufacturing apparatus suitable for manufacturing the above-described composite nonwoven fabric wiper according to the present invention will be described with reference to the drawings.
First, a schematic configuration of the nonwoven fabric wiper manufacturing apparatus 1 will be described. The production apparatus 1 shown in FIG. 2 includes an airlaid apparatus 2, a spunbonded nonwoven fabric supply apparatus 3 for supplying a spunbonded nonwoven cloth, and a suction apparatus 4 on the upstream side. The suction device 4 is arranged to face the lower side of the air-laid device 2.
Downstream from these devices 2, 3, and 4 in the web transport direction TD, a water entanglement device 5, a suction device 6, and a drying device 7 for jetting a water jet for performing a water entanglement process are sequentially provided from the upstream side. Are located. A winding device 8 for winding the continuously manufactured nonwoven fabric wiper WP is further provided downstream of the drying device 7.

  The air-laid apparatus 2 is configured to open a raw fiber pulp RP in which fibers are densely formed into a sheet form into pulp fibers, or a pulp fiber PF that has been blown with a blower (not shown) to an air-laid hopper 23. And a duct 22 for carrying.

An air-laid hopper 23 is disposed downstream of the duct 22. Inside the air-laid hopper 23, the pulp fibers in the defibrated state are designed to descend while dispersing, and gradually pile up at the lamination position 24 set on the lower surface to form the pulp fiber web PFW.
The suction device 4 is provided facing the lower side of the stacking position 24. More specifically, the suction device 4 has a suction portion 42 on the upper surface of the device main body 41, and the suction portion 42 moves the stacking position 24 so as to apply a suction force (negative pressure) to the pulp fiber web PFW. It has been set.
Note that FIG. 2 illustrates a case where the pulp fiber web PFW is formed by arranging the air-laid hopper 23 and the suction device main body 41 one by one in one stage. However, the arrangement is not limited to this, and the arrangement of the air-laid hopper 23 and the suction device main body 41 may be changed to two or more multi-stages according to the basis weight (basis weight) and the production speed of the pulp fiber web PFW.

A transport wire 43 for transporting the web is provided around the suction device 4. The transport wire 43 can be placed on the pulp fiber web PFW on which the pulp fibers PF are deposited at the stacking position 24, and is arranged to transport the web to the downstream side. However, the pulp fiber web PFW is not directly placed on the transport wire 43. This will become clear in the following description.
The transport wire 43 is formed in an opening form (mesh) such that the suction force of the suction portion 42 extends to the opposite side (upper side).

A spunbonded nonwoven fabric supply device 3 is arranged below the airlaid device 2 and upstream of the suction device 4. The spunbonded nonwoven fabric SW prepared in advance is set in a roll shape in the spunbonded nonwoven fabric supply device 3. That is, as described above, the spunbonded nonwoven fabric SW, in which the elongation in the lateral direction is suppressed more than the conventional spunbonded nonwoven fabric, is formed into a roll shape, pulled out from the spunbonded nonwoven fabric supply device 3, and supplied with the transport wire 43 described above. And is conveyed to the lamination position 24. Here, the longitudinal direction MD of the above-described spunbonded nonwoven fabric SW coincides with the web transport direction TD of the present manufacturing apparatus 1.
In addition, it is preferable that the spunbonded nonwoven fabric / the pulp fiber web, which is the weight composition ratio of the spunbonded nonwoven fabric and the pulp fiber web, is adjusted to 50/50 to 10/90 (wt%).

  The pulp fiber web PFW described above is placed on the spunbonded nonwoven fabric SW located at the lamination position 24. At that time, at the laminating position 24, the suction force of the suction part 42 of the suction device 4 passes through the transport wire 43 and acts on the spunbonded nonwoven fabric SW and the pulp fiber web PFW thereon. Therefore, the preliminary laminate PWeb (laminated web) in which the spunbonded nonwoven fabric SW and the pulp fiber web PFW are laminated is transported to the downstream side.

The preliminary stacked body PWeb is maintained in a stacked state by being suction-compressed by the suction force of the suction device 4. At this time, the fibers of the upper pulp fiber web PFW are in a dense state. However, when the preliminary laminate PWeb is transported and charged into the downstream hydroentanglement device 5 as it is, a part of the pulp fiber PF may be soared by the water jet (high-pressure water flow).
Therefore, in the present manufacturing apparatus 1, the sandwiching roller 28 for stabilizing the mounting state of the pulp fiber web PFW on the spunbonded nonwoven fabric SW with the preliminary laminate PWeb sandwiched from above and below, and the upstream of the hydroentangler 5 On the side, a pre-wetting device 30 for providing moisture for preventing fiber scattering is provided. Prewetting device 30 preferably applies a suction force from spray nozzle 31 for spraying water mist from above preliminary laminate PWeb and the lower side of preliminary laminate PWeb (that is, the lower surface of pulp fiber web PFW). The suction device 32 is included.

Although FIG. 2 illustrates a case where the pre-wetting device 30 is provided as a new device in front of the hydroentanglement device 5 as described above, the present invention is not limited to this. With respect to a plurality of sets including a water jet head 51 and a suction device 52, which will be described later, included in the hydroentanglement device 5, a design change may be made such that the set located at the head is used as the pre-wet device 30. In this case, adjustment may be made so that low-pressure water mist is sprayed from the head water jet head 51.
In the case of the water entanglement device 5 in which the number of sets of the water jet head 51 and the suction device 52 sufficient for performing the water entanglement process is secured, the leading water jet head 51 and the suction device 52 are pressed as described above. Utilization as a wet device is effective in controlling the cost of the equipment.

Then, in the water entanglement device 5, the entanglement between the pulp fibers is promoted by spraying a high-pressure water jet on the preliminary laminate PWeb that has been processed by the holding roller 28 and the pre-wet device 30, which are the pretreatment unit. This promotes integration of the pulp fiber web PFW layer located on the upper side and the spunbonded nonwoven fabric SW layer located on the lower side (water entanglement treatment).
The water entanglement device 5 exemplarily shown in FIG. 2 has water jet heads 51 arranged in multiple stages (four stages are illustrated in FIG. 2) along the transport direction TD.
FIG. 2 does not show the state of the nozzles provided on the water jet head 51 extending in a direction perpendicular to the transport direction TD (the width direction of the web). The jet nozzle is located at an appropriate position. The hole diameter φ of this water jet nozzle is preferably 0.06 to 0.15 mm, more preferably 0.10 to 0.12 mm. The interval between the water jet nozzles is preferably 0.4 to 1.0 mm.

  The water pressure at the time of performing the hydroentanglement treatment is desirably set in consideration of the basis weight of the pulp fiber web PFW and the spunbond nonwoven fabric SW. For example, it is preferable to select in the range of 1 to 30 MPa.

A suction device 52 is provided so as to face the water jet head 51. The suction force of the suction device 52 is applied to the lower side of the spunbonded nonwoven fabric SW located on the lower side while spraying the high-pressure water jet from the water jet head 51 on the pulp fiber web PFW located on the upper side. By the cooperative action of the water jet head 51 and the suction device 52, the pulp fiber on the pulp fiber web PFW side enters the lower spunbonded nonwoven fabric SW or reaches the opposite side through the spunbonded nonwoven fabric SW. It is presumed that a closed state is formed. The action promotes integration of the two layers.

The water entanglement device 5 is also provided with a transport wire 55. The transport wire 55 receives the preliminary laminate PWeb downstream of the pre-processing units 28 and 30 and transports the preliminary laminate PWeb into the hydroentanglement device 5. The transport wire 55 is disposed so as to pass between the water jet head 51 and the suction device 52 of the hydroentanglement device 5 from the upstream side to the downstream side.
Therefore, the preliminary laminate PWeb conveyed on the conveying wire 55 is subjected to more hydroentanglement processing toward the downstream in the conveying direction TD, and the upper pulp fiber when exiting the hydroentanglement device 5 A sufficient entanglement treatment between the web PFW layer and the lower spunbonded nonwoven fabric SW layer is realized.
The nonwoven fabric immediately after leaving the hydroentanglement device 5 is in a wet state, and the connection between the pulp fibers and the like is not sufficiently established.

Therefore, as shown in FIG. 2, on the downstream side of the hydroentanglement device 5, a suction device 6 and a drying device for sucking and removing water remaining on the web and thereafter performing drying to complete the production of the nonwoven fabric WP. 7 are deployed. As described above, when the dehydration and drying are performed by the suction device 6 and the drying device 7 at the later stage of the production of the nonwoven fabric WP, the nonwoven fabric can be efficiently produced, and the produced nonwoven fabric after hydroentanglement can be dried without applying a large external pressure. Since a nonwoven fabric can be manufactured, it can be finished into a bulky product.
The suction device 6 dehydrates the nonwoven fabric after the hydroentanglement by, for example, a vacuum method. The drying device 7 preferably employs a non-compression dryer, preferably an air-through dryer. In FIG. 2, a rotatable dryer main body 71 of an air through dryer is a cylindrical body, and a large number of through holes are provided in a peripheral surface thereof. It is preferable to adopt a configuration in which air is sucked toward the side.
The composite nonwoven fabric WP continuously manufactured as described above is wound by the roller 81 of the winding device 8 to complete a series of steps.

According to the nonwoven fabric wiper manufacturing apparatus 1 described above, the pulp fiber according to the present invention described above is prevented from falling off, and a nonwoven fabric wiper having excellent strength can be reliably manufactured.
In the embodiment of FIG. 2 described above, the case where the pulp fiber web is manufactured by a dry process using dry air laid is described, but the present invention is not limited to this. Even if the pulp fiber web is manufactured by applying the method for manufacturing a wet papermaking sheet, the same effects as those described above can be obtained.

  The description of the embodiment is finished above, but it is needless to say that the present invention is not limited to the above-described embodiment, and can be variously modified and implemented without departing from the gist thereof.

DESCRIPTION OF SYMBOLS 1 Nonwoven fabric wiper manufacturing device 2 Airlaid device 3 Spunbonded nonwoven fabric supply device 4 Suction device 5 Water entanglement device 6 Suction device 7 Drying device 8 Winding device 21 Fibrillator 22 Duct 23 Airlaid hopper 24 Stacking position 28 Nipping roller 30 Prewetting device 31 Spray nozzle 32 Suction device 41 Suction device main body 42 Suction section 43 Transfer wire 51 Water jet head 52 Suction device 55 Transfer wire SW Spunbond nonwoven fabric MP Fusion point MD Vertical direction CD Horizontal direction PF Pulp fiber PFW Pulp fiber web PWeb Preliminary lamination Body (laminated web)
WP Non-woven wiper TD Transport direction

Claims (6)

A composite nonwoven wiper in which a pulp fiber web is laminated and integrated on a spunbond nonwoven,
The non-woven fabric according to claim 1, wherein the spun-bonded non-woven fabric has an elongation of 5% or less in the lateral direction when a load of 0.5N is applied in a lateral direction perpendicular to a fiber flow direction. Wiper.   In the spunbonded nonwoven fabric, the elongation percentage is adjusted based on the arrangement density and / or shape in the lateral direction of the fusion points connecting the resin fibers constituting the spunbonded nonwoven fabric to each other, The nonwoven fabric wiper according to claim 1, wherein:   The nonwoven fabric wiper according to claim 2, wherein an area ratio of the fusion point is 5 to 20%.   The nonwoven fabric wiper according to any one of claims 1 to 3, wherein the fiber diameter of the spunbonded nonwoven fabric is 0.6 to 5.6 decitex.   The spunbonded nonwoven fabric / pulp fiber web, which is the weight composition ratio of the spunbonded nonwoven fabric and the pulp fiber web, is 50/50 to 10/90 (wt%). A nonwoven fabric wiper according to any of the claims. A method for producing a nonwoven fabric wiper according to any one of claims 1 to 5,
At least including a hydroentanglement step of hydroentanglement processing the spunbond nonwoven fabric and the pulp fiber web,
The hole diameter φ of the water jet nozzle that injects the water jet in the water entanglement step is 0.06 to 0.15 mm, and the interval between the water jet nozzles is 0.4 to 1.0 mm. A method for manufacturing a nonwoven wiper.

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