JP2630164B2 - Manufacturing method of water-absorbent wipe - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a water-absorbent wipe used as a disposable hand wipe, a wet tissue, a wiper, a disposable rag, and the like.

[0002]

2. Description of the Related Art Conventionally, as a wiping cloth for disposable hand wiping or the like, a dry pulp sheet in which pulp fibers are accumulated in a bulky manner, which is impregnated with water, a chemical or the like, has been used. However, the dry pulp sheet has a drawback that the wet strength after being impregnated with water or chemicals is low, and the sheet is easily broken during use.

[0003] On the other hand, a nonwoven fabric obtained by accumulating rayon fibers, which are hydrophilic fibers, and then bonding the rayon fibers together with a rubber-based binder is impregnated with water or the like. This wiping cloth exhibits high wet strength since the rayon fibers are bonded to each other. However, since the wiping cloth contains a rubber-based binder, there is a drawback that an unpleasant odor is generated. In addition, there is also a disadvantage that the feeling of use of the wiping cloth is poor due to the rough touch of the rubber-based binder. For this reason, attempts have been made to use a nonwoven fabric in which rayon fibers are entangled without using a rubber-based binder. For entanglement between rayon fibers, it is conceivable to apply a water column flow to the nonwoven fabric on which the rayon fibers are accumulated. However, when a non-woven fabric made of rayon fiber is used as a wiping cloth, there are fatal drawbacks as described below. That is, since the rayon fiber is a hydrophilic fiber, it absorbs water and swells, and its rigidity may be extremely reduced. And, due to the decrease in rigidity,
In some cases, the repulsive force when gripped with fingers is reduced, and when used as a wiping cloth, it is sometimes difficult to use.

[0004]

For this reason, the present inventors have attempted to produce a wiping cloth using hydrophobic fibers such as polypropylene fibers and polyester fibers instead of hydrophilic rayon fibers. Since the wiping cloth composed of the hydrophobic filament alone does not have sufficient water absorption, for example, a laminate in which the nonwoven composed of rayon fiber is bonded to the nonwoven composed of the accumulated hydrophobic filament is used as the wiping cloth. Tried. However, in this case, only one surface of the nonwoven fabric made of hydrophobic long fibers (the surface on which the nonwoven fabric made of rayon fibers is disposed) is water-absorbing, and the other surface (the surface on which the nonwoven fabric made of rayon fibers is not disposed). ) Had almost no water absorption and could not be used as a wipe. For this reason, it is conceivable to combine a nonwoven fabric made of rayon fibers on both sides of a nonwoven fabric in which hydrophobic long fibers are accumulated, but such a three-layer laminate is thick and extremely flexible. In some cases, making it difficult to use as a wipe.

[0005] A water column flow is applied to a laminate obtained by laminating a paper sheet on a nonwoven fabric made of a hydrophobic long fiber,
An attempt was made to produce a wiping cloth in which hydrophobic long fibers and pulp fibers constituting a paper sheet were entangled. However, in general, pulp fibers tend to be unevenly distributed only on one surface (the surface on which the paper sheet is laminated and abutted) of the nonwoven fabric made of hydrophobic long fibers, and on the other surface (the surface on which the paper sheet is not abutted). Often the water absorption was not sufficient. For this reason,
By laminating paper sheets on both sides of a non-woven fabric made of hydrophobic long fibers, and applying a water column flow to the front and back surfaces of this laminate,
It is also conceivable to produce a wipe. However, this method has a regret that the lamination step and the water column flow treatment step become complicated. Furthermore, if the water column flow treatment is insufficient,
There was a regret that the pulp fiber and the hydrophobic long fiber were not sufficiently entangled with each other, and the paper sheet was easily peeled off or the pulp fiber was easily dropped when used as a wiping cloth.

Accordingly, the present invention provides a long-fiber non-woven fabric made of hydrophobic long fibers and a pulp fiber substantially.
By applying a high-pressure water column flow under certain conditions to a laminate obtained by laminating paper sheets formed by bonding pulp fibers with each other ,
The pulp fiber is also exposed on the surface of the long-fiber non-woven fabric where the paper sheet is not in lamination contact, and the hydrophobic long fiber and the pulp fiber are tightly entangled, so that the water absorption on both sides of the wiping cloth is reduced. Made of a wiping cloth that is good, has little decrease in rigidity even after absorbing water, and is excellent in handling during use
It is intended to provide a manufacturing method .

[0007]

That is, the present invention relates to a long-fiber nonwoven fabric in which a large number of hydrophobic long fibers are accumulated ,
And the pulp fibers are connected to each other.
From the paper sheet side
It is defined by the following formula so as to penetrate the long fiber nonwoven fabric side.
The added energy E will be 0.1-0.8kwh
As described above, by applying a high-pressure water column flow,
When the pulp fibers are entangled with each other,
The fiber is placed on the non-contact surface of the long-fiber nonwoven fabric,
The present invention relates to a method for producing a water-absorbent wiping cloth, characterized by exposing 2% by area or more to the area . Note that E = (QρV ² ) / 2, where E is the additional
Q represents the water required for processing 1 kg of the laminate.
, Ρ represents the specific gravity of the water used, and V represents
Indicates the flow velocity of the high pressure water column flow. ]

The method for producing a water-absorbent wipe according to the present invention is described below .
In its, first, a long-fiber nonwoven fabric in which a large number of hydrophobic filaments formed by integrated, the pulp is comprised substantially of pulp fibers
A paper sheet in which fibers are bonded to each other is prepared . As the hydrophobic long fibers constituting the long-fiber nonwoven fabric, any conventionally known hydrophobic long fibers can be used. For example, polyamide long fibers such as nylon, polyacrylate long fibers, polyolefin long fibers such as polypropylene and polyethylene, polyester long fibers such as polyethylene terephthalate, and the like can be used alone or in combination. . In the present invention, the reason for using long fibers is that long fibers are more excellent in tensile strength and form stability when entangled between fibers than short fibers. Further, in the case of a long fiber, even if a high-pressure water column flow is applied, it is hard to be lost together with the water column flow. Further, the fineness of the hydrophobic long fiber is preferably from 1 to 4 denier, and most preferably from 1.5 to 3 denier. When the fineness of the hydrophobic long fiber exceeds 4 denier, the bending rigidity of the hydrophobic long fiber becomes too high, and the flexibility when used as a wiping cloth tends to decrease. Conversely, if the fineness of the hydrophobic long fiber is less than 1 denier, the manufacturing conditions of the hydrophobic long fiber become strict, and it becomes difficult to manufacture the hydrophobic long fiber at a high speed, which is not practical.

The basis weight of the long-fiber nonwoven fabric is 5 to 30 g /
m ² is preferred. The basis weight of long fiber nonwoven fabric is 30g /
Beyond m ^2, the stack of paper sheets and the long-fiber nonwoven fabric,
Even when a high-pressure water column flow is applied from the paper sheet side to the long-fiber non-woven fabric side, the pulp fibers constituting the paper sheet still have the back surface of the long-fiber non-woven fabric (the surface not in contact with the paper sheet, ie, the non-contact surface).
The pulp fibers are unevenly distributed only on one side of the obtained wiping cloth, and the water absorption on the non-contact surface of the long-fiber nonwoven fabric with few pulp fibers tends to decrease. Conversely, if the basis weight of the long-fiber nonwoven fabric is less than 5 g / m ² , the morphological stability of the long-fiber nonwoven fabric will decrease, and the wet strength of the obtained wiping cloth will tend to decrease. Furthermore, the gap between the hydrophobic long fibers becomes large, and when a high-pressure water column flow is applied, pulp fibers flow out from the gap,
When the high pressure water column flow after use is recovered, a large amount of pulp fiber may be mixed therein. In addition, the long-fiber nonwoven fabric used in the present invention may be a so-called long-fiber nonwoven fabric in which hydrophobic long fibers are self-fused, or a fleece-like non-bonded long filament nonwoven fabric. It may be a long-fiber nonwoven fabric. In particular, among the former long-fiber nonwoven fabrics, it is preferable to use a nonwoven fabric in which a large number of spot-fused areas where hydrophobic long fibers are self-fused are scattered. The reason is that there is a point fusion area in which the hydrophobic filaments are self-fused, so that the shape stability is excellent, and in areas other than the point fusion area, the hydrophobic filaments are self-fused. This is because they are not attached and are accumulated in a free state, so that they are excellent in flexibility and easily entangled with pulp fibers.

As the pulp fibers constituting the paper sheet used in the present invention, conventionally known pulp fibers can be arbitrarily used. For example, a chemical pulp fiber obtained by treating coniferous or hardwood wood by a kraft method, a sulfite method, a soda method, a polysulfide method, or the like, or a mechanical pulp fiber treated by a refiner, a grinder, or the like can be used. This pulp fiber may be used as bleached pulp fiber or may be used as it is as unbleached pulp fiber. Further, the above pulp fibers may be used alone or in combination. When using a mixture of softwood pulp fiber and hardwood pulp fiber, the softwood pulp fiber / hardwood pulp fiber = 100-20 / 0-80, preferably 100-40 / 0-60. preferable.
If the mixing ratio of the hardwood pulp fiber exceeds 80% by weight, the hardwood pulp fiber is less likely to be entangled with the hydrophobic long fiber than the softwood pulp fiber. , Tend to be washed away. In addition, since hardwood pulp fibers have relatively high rigidity, there is a tendency that the flexibility of the obtained wipe is reduced.

[0011] The paper sheet is substantially composed of pulp fibers.
Have been. That is, fibers other than pulp fibers, such as rayon
Staples or synthetic fiber staples are substantially
Is not mixed. Also, paper sheet
The pulp fibers in the pulp are interconnected. Say here
The bonding is performed by wet-making the pulp fiber-containing stock and drying it.
Pulp fiber that occurs when
I taste. Therefore, the paper sheet referred to in the present invention is
Widely used in wet papermaking using paper fibers
Paper, which is nothing special.
In general, it is preferable to use thin paper as such a paper sheet. The basis weight of paper sheet is JIS P 8
124 to 10 to 100 g / m.
^{About 2} is preferable. When the basis weight of the paper sheet is less than 10 g / m ² , the absolute amount of the pulp fiber is small, and it tends to be difficult to provide the obtained wiping cloth with sufficient water absorption and water retention. Conversely, if the basis weight of the paper sheet exceeds 100 g / m ² , the absolute amount of pulp fibers is too large, and even if a high-pressure water column flow is applied to the paper sheet, each pulp fiber becomes entangled with a hydrophobic filament. There is a tendency that it is difficult to give a sufficient amount of exercise. Furthermore, the absolute amount of pulp fibers is too large, and the resulting wipes tend to be less flexible. The density of the paper sheet is 0.7 g / cm ³ or less, and preferably 0.6 g / cm ³ , measured by the method described in JIS P 8118.
/ Cm ³ or less. When the density of the paper sheet exceeds 0.7 g / cm ³ , the motion of the pulp fiber is suppressed even when a high-pressure water column flow is applied to the paper sheet, and the hydrophobic long fiber and the pulp fiber tend not to be entangled. Occurs.

The above-described long-fiber nonwoven fabric and paper sheet are laminated to form a laminate. In this laminate,
The ratio of the basis weight of the long-fiber nonwoven fabric to the paper sheet is the long-fiber nonwoven fabric:
It is preferable that paper sheet = 1: 1 to 19.
When the long-fiber nonwoven fabric: paper sheet is less than 1: 1, the amount of pulp fiber is relatively reduced with respect to the amount of hydrophobic long fiber, and the water absorption and water retention of the obtained wiping cloth tend to decrease. Occurs. In addition, a reduction in the amount of inexpensive pulp fibers relative to hydrophobic long fibers tends to increase the cost of the obtained wipe. Conversely, if the basis weight of the paper sheet exceeds 1: 19 and the fiber weight of the paper sheet exceeds 1:19, all of the pulp fibers constituting the paper sheet become less likely to be strongly entangled with the hydrophobic long fibers, and When the wiping cloth to be used is wet, the pulp fibers tend to fall off. In addition, the amount of the hydrophobic long fibers is relatively reduced, and the tensile strength and the like of the obtained wiping cloth tend to decrease.

Next, a high-pressure water column flow is applied to the laminate. This high-pressure water column flow is obtained by ejecting water at a high pressure through a nozzle hole having a fine diameter. For example, through a nozzle hole having a hole diameter of about 0.01 to 0.3 mm, 20 to
It is obtained by ejecting water at a pressure of about 150 kg / cm ² . When this high-pressure water column flow is applied to the laminate so as to penetrate from the paper sheet side to the long fiber web side, the high-pressure water column flow first collides with the paper sheet. Then, the paper sheet is set on the long-fiber nonwoven fabric, and then the paper sheet is broken in the set state, and the paper sheets are bonded together in the paper sheet.
The pulp fibers are separated from each other and isolated into each pulp fiber. Next
In addition, the isolated pulp fiber undergoes deformation such as bending and twisting, and at the same time, kinetic energy is sufficiently given to the pulp fiber to cause random movement in the pulp fiber. As a result, the pulp fibers and the hydrophobic long fibers in the long-fiber nonwoven fabric are entangled by these combined actions, and the pulp fibers also entangle the hydrophobic long fibers.

What is important in the present invention is that when applying a high pressure water column flow, the added energy is 0.1 to 0.8 k.
wh, preferably 0.15 to 0.8 kwh. Here, the added energy is equivalent to E defined by the following equation. That is, E = (Q
ρV ² ) / 2 [where E represents the added energy of the high pressure water column flow, Q represents the amount of water required for treating 1 kg of the laminated body, ρ represents the specific gravity of the water used, and V represents the high pressure water column flow. Indicates the flow rate. ]. Additional energy E is 0.1k
If it is less than wh, the pulp fibers constituting the paper sheet are less likely to be exposed on the non-contact surface of the long-fiber nonwoven fabric,
Not preferred. That is, the pulp fiber is less than 2% by area based on the surface area of the long-fiber nonwoven fabric on the non-contact surface, which is not preferable. Here, the exposure ratio of pulp fibers to the non-contact surface of the long-fiber nonwoven fabric (area%)
Is measured by the following method. That is, the non-contact surface of the long-fiber nonwoven fabric of the wiping cloth obtained by applying the high-pressure water column flow is taken with an optical microscope photograph at a magnification of 20 times, and the pulp fiber is obtained from the obtained image using an image analyzer. The area ratio of the portion is determined by the following equation. That is, the exposure ratio (area%) of the pulp fiber = [(the occupied area of the pulp fiber on the non-contact surface of the long-fiber nonwoven fabric / the total surface area on the non-contact surface side of the long-fiber nonwoven fabric)] × 100. Then, the measurement area of each optical microscope photograph was set to 0.25 cm ^2, and 20 such photographs were taken at random to determine the exposure ratio of the pulp fiber to 20 points.
The average value was defined as the pulp fiber exposure ratio (area%) in the present invention. On the other hand, the added energy E is 0.8 k
With more than wh, pulp fibers that make up the sheet of paper
The non-contact surface (paper
Sheet on the opposite side of the sheet)
Therefore, it is not preferable. That is, the pulp fibers are non-woven
When it flows out of the non-contact surface of the cloth, the resulting water-absorbent wipe
Content of pulp fiber in water and water absorption is reduced
Is not preferred. Also, the pulp fibers that have flowed out are not
High-pressure water column after use
When the stream is treated as a waste liquid, clogging of the filter material is likely to occur.
This increases the number of times the filter material needs to be replaced, which is not preferable.

The wiping cloth according to the present invention is manufactured as described above. The wiping cloth is laminated with a long-fiber nonwoven fabric and a paper sheet. And the pulp fibers are intertwined with each other, and the pulp fibers are exposed on the non-contact surface of the long-fiber nonwoven fabric by 2% by area or more, preferably 4% by area or more based on the surface area of the long-fiber nonwoven fabric. It is doing. When the exposed amount of the pulp fiber on the non-contact surface of the long-fiber nonwoven fabric is less than 2 area% with respect to the surface area of the long-fiber nonwoven fabric, water absorption on the surface is not sufficient, and it is preferable to use it as a wiping cloth. Absent. In the wiping cloth according to the present invention, pulp fibers exist in the following distribution in the thickness direction. In other words, the distribution is minimized at the non-contact surface of the long-fiber nonwoven fabric, rapidly increases from the non-contact surface to the contact surface with the paper sheet, and is maximized at this contact surface. . Therefore, since the pulp fibers are present throughout the entire thickness of the wipe, good water absorption and water retention are exhibited as a whole. The wiping cloth as described above is used as it is, or, if desired, provided with a humectant such as water or propylene glycol, an antibacterial agent such as alcohols or parabenzoic acid, a fungicide, a fragrance or the like, Disposable hand towel,
It is used as a wet tissue, wiper, disposable rag, etc.

[0016]

【Example】

Example 1 A long-fiber nonwoven fabric was prepared in which polypropylene long fibers were accumulated, and had many point fusion areas in which the polypropylene long fibers were self-fused with each other. The fineness of the polypropylene long fibers constituting the long-fiber nonwoven fabric was 2.5 denier, and the basis weight of the long-fiber nonwoven fabric was 10 g / m ² .
A paper sheet containing no fibers other than pulp fibers was laminated on the surface of the long-fiber nonwoven fabric. This paper sheet is
The grammage measured by the method described in SP 8124 was 40 g / m ² . This paper sheet was obtained by wet papermaking of bleached softwood kraft pulp fibers. Then, the paper sheets were placed on the upper side and the long-fiber nonwoven fabric was placed on the lower side, and the sheets were placed on a transfer conveyor. Then, while transferring the laminate with this transfer conveyor, the hole diameter 0.12mm
Nozzle holes of using a high pressure water column flow ejection device are arranged at intervals of 16 / cm, thereby ejecting a high pressure water column flow water pressure of 50 kg / cm ^2, through the surface of the paper sheet to the back of the long-fiber nonwoven fabric In this way, a high-pressure water column flow was applied. The added energy per 1 kg of this high-pressure water column flow is 0.32 kwh
Met. As described above, the pulp fibers constituting the paper sheet and the polypropylene long fibers constituting the long-fiber nonwoven fabric were entangled to obtain an integrated wiping cloth.
In the obtained wipe, 10% by area of the pulp fiber was exposed on the non-contact surface of the long-fiber nonwoven fabric.

Example 2 Polyethylene terephthalate long fibers were accumulated,
In addition, a long-fiber nonwoven fabric having a large number of point-fusion areas where the polyethylene terephthalate long fibers were self-fused was prepared. The fineness of the polyethylene terephthalate long fibers constituting the long-fiber nonwoven fabric was 2.0 denier, and the basis weight of the long-fiber nonwoven fabric was 15 g / m ² . A paper sheet containing no fibers other than pulp fibers was laminated on the surface of the long-fiber nonwoven fabric. This paper sheet had a basis weight of 40 g / m ² measured by the method shown in JIS P 8124. In addition,
This paper sheet is obtained by wet papermaking of bleached softwood kraft pulp fibers. Then, the paper sheet is positioned on the top, the long fiber nonwoven fabric is positioned on the bottom, and laminated,
It was placed on a transfer conveyor. While transferring the laminate by this transfer conveyer, using a high-pressure water column flow jetting device in which nozzle holes with a hole diameter of 0.12 mm are arranged at an interval of 16 / cm, 80 kg /
A high-pressure water column flow was ejected at a water pressure of cm ² , and a high-pressure water column flow was applied so as to penetrate from the paper sheet side to the long-fiber nonwoven fabric side.
Note that the added energy of the high-pressure water column flow per 1 kg of the laminated body was 0.8 kwh. As described above, the pulp fibers constituting the paper sheet and the polyethylene terephthalate long fibers constituting the long-fiber nonwoven fabric are entangled,
An integrated wipe was obtained. In the obtained wipe, 20% by area of pulp fibers were exposed on the non-contact surface of the long-fiber nonwoven fabric.

Example 3 A long-fiber non-woven fabric was prepared in which polypropylene long fibers were accumulated, and had many point-fusion areas where the polypropylene long fibers were self-fused. The fineness of the polypropylene long fibers constituting this long-fiber nonwoven fabric was 3 deniers, and the basis weight of the long-fiber nonwoven fabric was 25 g / m ² . A paper sheet containing no fibers other than pulp fibers was laminated on the surface of the long-fiber nonwoven fabric. This paper sheet is JIS
The grammage measured by the method shown in P 8124 was 40 g / m ² . This paper sheet was obtained by wet-making a mixture of 80% by weight of bleached softwood kraft pulp fiber and 20% by weight of bleached hardwood kraft pulp. Then, the paper sheets were placed on the upper side and the long-fiber nonwoven fabric was placed on the lower side, and the sheets were placed on a transfer conveyor. Then, while transferring the laminated body by this transfer conveyor, a high-pressure water column was jetted at a water pressure of 60 kg / cm ² by using a high-pressure water column jet device in which nozzle holes having a diameter of 0.15 mm were arranged at intervals of 10 / cm. Was ejected, and a high-pressure water column flow was applied so as to penetrate from the surface of the paper sheet to the back surface of the long-fiber nonwoven fabric. The added energy of the high-pressure water column flow per 1 kg of the laminate was 0.4 kwh. As described above, the pulp fibers constituting the paper sheet and the polypropylene long fibers constituting the long-fiber nonwoven fabric were entangled to obtain an integrated wiping cloth. In the obtained wipe, 6% by area of pulp fibers were exposed on the non-contact surface of the long-fiber nonwoven fabric.

Example 4 A long-fiber non-woven fabric was prepared in which polypropylene long fibers were accumulated and had many point-fused areas where the polypropylene long fibers were self-fused. The fineness of the polypropylene long fibers constituting this long-fiber nonwoven fabric was 2.5 denier, and the basis weight of the long-fiber nonwoven fabric was 15 g / m ² .
A paper sheet containing no fibers other than pulp fibers was laminated on the surface of the long-fiber nonwoven fabric. This paper sheet is
The basis weight measured by the method described in SP 8124 was 50 g / m ² . This paper sheet was obtained by wet papermaking of bleached softwood kraft pulp fibers. Then, the paper sheets were placed on the upper side and the long-fiber nonwoven fabric was placed on the lower side, and the sheets were placed on a transfer conveyor. Then, while transferring the laminate with this transfer conveyor, the hole diameter 0.12mm
Nozzle holes of using a high pressure water column flow ejection device are arranged at intervals of 16 / cm, thereby ejecting a high pressure water column flow water pressure of 40 kg / cm ^2, through the surface of the paper sheet to the back of the long-fiber nonwoven fabric In this way, a high-pressure water column flow was applied. The added energy per 1 kg of this high pressure water column flow is 0.15 kwh
Met. As described above, the pulp fibers constituting the paper sheet and the polypropylene long fibers constituting the long-fiber nonwoven fabric were entangled to obtain an integrated wiping cloth.
In the obtained wipe, 4% by area of pulp fibers were exposed on the non-contact surface of the long-fiber nonwoven fabric.

Example 5 A long-fiber nonwoven fabric was prepared in which polypropylene long fibers were accumulated, and had many point-fused areas where the polypropylene long fibers were self-fused. The fineness of the polypropylene long fibers constituting this long-fiber nonwoven fabric was 2.5 denier, and the basis weight of the long-fiber nonwoven fabric was 15 g / m ² .
A paper sheet containing no fibers other than pulp fibers was laminated on the surface of the long-fiber nonwoven fabric. This paper sheet is
The grammage measured by the method described in SP 8124 was 80 g / m ² . This paper sheet was obtained by wet papermaking of bleached softwood kraft pulp fibers. Then, the paper sheets were placed on the upper side and the long-fiber nonwoven fabric was placed on the lower side, and the sheets were placed on a transfer conveyor. Then, while transferring the laminate by this transfer conveyor, the hole diameter 0.15mm
Nozzle holes of, using 10 / cm high-pressure water column flow jetting device arranged at intervals, thereby ejecting a high pressure water column flow water pressure of 80 kg / cm ^2, through the surface of the paper sheet to the back of the long-fiber nonwoven fabric In this way, a high-pressure water column flow was applied. The added energy per 1 kg of this high-pressure water column flow is 0.6 kwh
Met. As described above, the pulp fibers constituting the paper sheet and the polypropylene long fibers constituting the long-fiber nonwoven fabric were entangled to obtain an integrated wiping cloth.
In the obtained wipe, 16% by area of pulp fibers were exposed on the non-contact surface of the long-fiber nonwoven fabric.

Comparative Example 1 A wiping cloth was obtained in the same manner as in Example 1 except that the water pressure of the high-pressure water column flow was set to 15 kg / cm ² , and the added energy of 1 kg of the high-pressure water column flow was set to 0.05 kwh. The obtained wiping cloth has one pulp fiber on the non-contact surface of the long-fiber nonwoven fabric.
Only area% was exposed.

Comparative Example 2 A wiping cloth was obtained in the same manner as in Example 2 except that the water pressure of the high-pressure water column flow was set to 15 kg / cm ² , and the additional energy per 1 kg of the high-pressure water column flow was set to 0.08 kwh. The obtained wiping cloth has one pulp fiber on the non-contact surface of the long-fiber nonwoven fabric.
Only area% or less was exposed.

Comparative Example 3 A long-fiber non-woven fabric was prepared in which long polypropylene fibers were accumulated, and had many point-fused areas where the long polypropylene fibers were self-fused. The fineness of the polypropylene long fibers constituting this long-fiber nonwoven fabric was 2.3 denier, and the basis weight of the long-fiber nonwoven fabric was 40 g / m ² .
A paper sheet containing no fibers other than pulp fibers was laminated on the surface of the long-fiber nonwoven fabric. This paper sheet is
The basis weight measured by the method shown in SP 8124 is 30 g / m
² (weight ratio of long-fiber nonwoven fabric to paper sheet was 1: 0.75). This paper sheet was obtained by wet-making a mixture of 80% by weight of bleached softwood kraft pulp fiber and 20% by weight of bleached hardwood kraft pulp. Then, the paper sheets were placed on the upper side and the long-fiber nonwoven fabric was placed on the lower side, and the sheets were placed on a transfer conveyor. Next, the water pressure of the high-pressure water column flow was set to 20 kg / cm ² ,
A wiping cloth was obtained in the same manner as in Example 3, except that the added energy per kg was 0.08 kwh. The obtained wiping cloth contains 1% by area of pulp fibers on the non-contact surface of the long-fiber nonwoven fabric.
Only the following were exposed.

The wipes according to Examples 1 to 5 and Comparative Examples 1 to 3 were subjected to the following tests to evaluate the quality. The results are shown in Table 1.

[Table 1] Note 1) Water absorption: The water absorption of the surface (non-contact surface) where the long-fiber nonwoven fabric of the wiping cloth was not in contact with the paper sheet was determined by sensory evaluation. The sensory evaluation was performed in the following five stages. 5: Water was absorbed very quickly. 4: Water was immediately absorbed. 3
... water absorption was normal. 2: Slowly absorbed water. 1: It hardly absorbs water. 2) Wipeability: After wetting the surface (non-contact surface) where the long-fiber nonwoven fabric of the wiping cloth was not in contact with the paper sheet, the desk was rubbed with a lightly squeezed surface, and the wiping performance was evaluated organoleptically. The sensory evaluation was performed in the following five stages. 5 ... Wipeability is extremely excellent. 4 ... Wipeability is excellent. 3: The wiping properties are normal. 2: The wiping properties are somewhat poor. 1 ... Wipeability is poor. 3) Repeatability: The operation of immersing the wiping cloth in water, squeezing it gently, and then rubbing it by hand was repeated 10 times, and it was evaluated organoleptically whether tearing or peeling of the paper sheet would occur. The sensory evaluation was performed in the following five stages. 5: The paper sheet was not torn or peeled at all, and could be sufficiently used repeatedly. 4: Although the strength of the wipe was slightly reduced, it could be used repeatedly. 3: The strength of the wiping cloth was reduced, but it could withstand repeated use three to four times. 2
... The strength of the wiping cloth was reduced, and tearing and peeling of the paper sheet occurred. 1: The wipe was remarkably damaged, and repeated use was impossible. 4) Flexibility: The flexibility of the wipe was evaluated organoleptically. The sensory evaluation was performed in the following five stages. 5: Very soft touch feeling. 4: A flexible touch feeling. 3: The feel was normal. 2: It has a slightly hard feel. 1: A hard touch feeling.

As is clear from the results in Table 1, Examples 1 to
As compared with the wiping cloth according to No. 5, the wiping cloths according to Comparative Examples 1 to 3 have a smaller percentage of pulp fiber exposure on the surface (non-contact surface) where the long-fiber nonwoven fabric is not in contact with the paper sheet. It was inferior in water absorption and wiping properties of the contact surface. Further, in the wiping cloths according to Comparative Examples 1 to 3, since the pulp fibers constituting the paper sheet and the long fibers constituting the long-fiber nonwoven fabric are not sufficiently entangled with each other, peeling or tearing of the paper sheet occurs. However, repeated use was inferior. Furthermore, the wiping cloths according to Comparative Examples 1 to 3 are not sufficiently entangled with the pulp fiber and the long fiber as compared with the wiping cloths according to Examples 1 to 5, that is, the paper sheet maintains the original shape to some extent. Because of this, the flexibility was inferior.

[0026]

As described above, the water-absorbent wiping cloth obtained by the method according to the present invention has a structure in which a paper sheet and a long-fiber nonwoven fabric are laminated, and the pulp fiber and the pulp fiber constituting the paper sheet are combined with each other. The hydrophobic long fibers constituting the fibrous nonwoven fabric are sufficiently entangled with each other, and the pulp fibers are also exposed at a constant rate on the non-contact surface where the long fiber nonwoven fabric does not contact the paper sheet. Therefore, this wiping cloth formed by laminating a paper sheet and a long-fiber nonwoven fabric exhibits sufficient water absorption even on the paper sheet surface, and also has a sufficient nonwoven fabric contact surface on the long-fiber nonwoven fabric with the paper sheet. Exhibits water absorption. Therefore, this wiping cloth has an effect of being excellent in water absorption and excellent in wiping off dirt on any surface. In addition, since the long-fiber nonwoven fabric is formed by accumulating hydrophobic long fibers, even if water is absorbed, the rigidity of the hydrophobic long fibers does not extremely decrease. Therefore, when the wiping cloth is immersed in water or the like for use, the wiping cloth has rigidity or repulsion, and has an effect of being easily grasped by fingers and easily handled. Further, since each pulp fiber and long fiber are sufficiently entangled with each other, the pulp fiber is excellent in flexibility, and has excellent form stability, so that it has an effect of being excellent in repeated use. In addition, the water-absorbent wiping according to the present invention
The method of fabric production consists essentially of pulp fibers.
A paper sheet where the pulp fibers are bonded to each other and a long fiber
High pressure on nonwoven laminate with specific range of additional energy
In order to apply a water column flow, the pulp fibers that make up the paper sheet
Separation, entanglement of pulp fibers and hydrophobic rewoven fibers, nonwoven fibers
Exposure of the pulp fiber to the non-contact surface of the cloth is performed smoothly,
Efficiently obtain a water-absorbent wiping cloth having the above characteristics.
This has the effect of being able to In addition, high pressure water column flow
Because the added energy is within a certain range, pulp fiber
Is less likely to flow out of the non-contact surface of the long-fiber nonwoven fabric,
A desired amount of pulp fibers may be included in the resulting wipe
Therefore, it is said that the water absorption of the wiping cloth also decreases
Has the effect of In addition, the high pressure water column flow after use
Fiber is difficult to mix, so even when treating waste liquid
This has the effect of reducing the number of replacements.

Claims (1)

(57) [Claims] 1. A pulp comprising a long-fiber nonwoven fabric in which a large number of hydrophobic long fibers are accumulated , and pulp fibers which are substantially composed of pulp fibers
A laminated body obtained by laminating a paper sheet in which fibers are combined with each other has an additional energy E defined by the following formula of 0.1 so as to penetrate from the paper sheet side to the long fiber nonwoven fabric side.
Such that to 0.8 kwh, the applying pressure of water flow
The pulp fibers are entangled with each other.
And the pulp fiber is brought into contact with the non-contact surface of the long-fiber nonwoven fabric.
2% or more of the surface area of the long-fiber nonwoven fabric
A method for producing a water-absorbent wiping cloth, comprising: E = (QρV ² ) / 2 [where E represents the added energy of the high pressure water column flow, Q represents the weight of water required for treating 1 kg of the laminate, ρ represents the specific gravity of the water used, V represents the flow velocity of the high pressure water column flow. ]