JP2001200459A - Nonwoven fabric for wiping having flowing water degradability and method of production for the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a nonwoven fabric for wiping having flowing water degradability which has a tensile strength and a surface strength sufficient for the practical use in the work such as cleaning in a dry state and a wet state, is degradable in flowing water in large amount and is excellent in wiping property, feeling of touch and handleability; and a method of production for the same. SOLUTION: A nonwoven fabric for wiping having flowing water degradability prepared by integrating a web containing a cellulose natural fiber having strength developing performance substantially by hydrogen bond and a regenerated cellulose fiber, through entanglement by high pressure water flow. The nonwoven fabric has the marks of water flow attributable to the entanglement and the unevenness formed by a crape treatment.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a nonwoven fabric for wiping which has a surface strength and a tensile strength which can withstand wiping operations in a dry state and a wet state, and a method for producing the same. More specifically, the present invention is a nonwoven fabric for wiping having a water-disintegrating property in which a web containing a cellulosic natural fiber and a regenerated cellulose fiber having an ability to substantially develop strength by hydrogen bonding is entangled and integrated by a high-pressure water stream. The treatment reduces the loss of fibers and develops strength, suppresses the collapse of the nonwoven fabric during still water or wiping, and reduces the performance by imparting flexibility and volume by creping treatment, as well as imparting irregularities Without letting
The present invention relates to a nonwoven fabric for wiping, which has improved wiping properties, improved handling properties, and excellent running water disintegration properties.

[0002]

2. Description of the Related Art Non-woven fabrics for cleaning such as wet wipes, baby wipes, nursing care, makeup wipes, dirt removers, and other personal wipers, and object wipers such as cleaners, car wipers, industrial wipers, etc. It has come to be used in place of paper wipers and cloth waste.

Among these nonwoven fabrics for wiping, there are a dry wiper used in a dry state and a wet wiper used in a wet state. In recent years, wet wipes, wipes for baby butt, wipers for nursing care, and the like have been used. It is increasingly used for its simplicity. These wet wipers are obtained by impregnating a nonwoven fabric with water or a chemical agent at a ratio of about 2 to 3 times and moistening them, and have sufficient strength to perform wiping in a wet state. In addition, these wet wipers are generally packaged and provided in a sealed container, an aluminum-deposited bag, or the like to prevent evaporation of water and chemicals.

[0004] As a nonwoven fabric for wiping, a hydroentangled nonwoven fabric in which fibers are entangled by a dense high-pressure water flow is often used for applications requiring a tactile sensation. The hydro-entangled nonwoven fabric not only has excellent wiping properties,
Those that have a small amount of fluff and do not use a binder are particularly soft and have an excellent tactile sensation and do not damage the object, and are therefore widely used from objects to persons.

[0005] In the future, in particular, due to hygiene problems and the response to the aging society, it is expected that demand for wipers for baby's buttocks and nursing care wipers will increase in the future.

However, most of the nonwoven fabrics for wiping are obtained by subjecting a web obtained by a dry method to hydroentanglement treatment to satisfy practical surface strength and tensile strength. Staple fibers exceeding 1 inch are used. Have been.

[0007] Therefore, there is no disintegration property of running water in a flush toilet, and it has not yet reached a situation where it is used in place of toilet paper. Further, since the wiper containing the synthetic fiber does not decompose even when buried in the soil, there is also a problem that it is difficult to dispose of the wiper, and that it is difficult to treat the environment.

[0008] In order to cope with the problems of disintegration in running water and disposal, there are two types: one in which wet strength is enhanced by the action of a specific metal salt, and one in which a web of fibers having a specific fiber length is subjected to hydroentanglement treatment. Proposed.

For example, Japanese Patent Laid-Open Publication No.
No. 7335 describes that carboxymethylcellulose is used in a substrate. However, coexistence with metal ions is necessary in order to exhibit practical wet strength and to exhibit disintegration, which causes a problem on the human body and a problem of leaving a slimy feeling after use.

As an example of the latter, Japanese Patent Application Laid-Open No. 6-339449
The publication describes that a hydroentangled fiber web using a wet strength agent for pulp fibers and artificial fibers is used as a wet wipe. However, there is no specific description about disintegration in water, and the disintegration rate in water using a wet strength agent is slow, and it is difficult to use it in a practical use in flushing flush toilets.

In US Pat. No. 4,755,421, a hydroentangled disintegratable fabric using wood pulp and cellulose fibers disintegrates with gentle agitation and disintegrates in sewage and spoilage systems. There is a description. Here, the practical wet strength is described, but when used as a wet wiper, there is a concern about handling properties such that the nonwoven fabric wipers stick together during use, break when being separated, or become tangled when pulled out slowly.

JP-A-10-51051 and JP-A-1
No. 1-93055, as in the above-mentioned publications, is an entangled non-woven fabric mainly composed of wood pulp and regenerated cellulose fibers, and uses a specific pulp or controls the orientation of the web to use a binder. There is disclosed a method for achieving both strength and disintegration in running water, but there is no description about actual use as in the above-mentioned U.S. Patent.

[0013]

SUMMARY OF THE INVENTION It is an object of the present invention to provide, in a dry state and a wet state, a tensile strength and a surface strength that can withstand practical use in operations such as cleaning, and that a large amount of running water can be used. Another object of the present invention is to provide a nonwoven fabric for wiping, in which the nonwoven fabric for wiping disintegrates, has excellent wiping properties, tactile sensation and handleability, and has disintegration properties under running water, and a method for producing the same.

[0014]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems. As a result, a nonwoven fabric is obtained in which a web containing cellulose-based natural fibers and a regenerated cellulose fiber having the ability to substantially develop strength by hydrogen bonding is entangled and integrated, and irregularities are imparted by high-pressure water flow and crepe treatment, whereby the nonwoven fabric is formed. In addition to being soft and flexible, improved wiping, improved handling,
Unexpected effects such as suppression of fiber shedding during crepe treatment and improvement of water flow disintegration were found. The present invention has been achieved based on these findings.

That is, the present invention relates to (1) a wiping method having a water-disintegrating property in which a web containing cellulosic natural fibers and a regenerated cellulosic fiber substantially having an ability to develop strength by hydrogen bonding is entangled and integrated by a high-pressure water flow. In a nonwoven fabric, the present invention is achieved by a nonwoven fabric for wiping, which has water flow traces due to entanglement and irregularities formed by creping and has flowing water disintegration properties.

(2) The nonwoven fabric for wiping according to the above (1), which has a crepe ratio of 5 to 30%.

(3) The disintegration time of the wiping nonwoven fabric measured in accordance with the evaluation method for ease of loosening described in 4.5 of JIS P 4501 is 300 seconds or less. Or the nonwoven fabric for wiping according to (2).

(4) The above (1), (2) or (3), wherein the natural cellulose fiber is wood pulp.
2. The nonwoven fabric for wiping having disintegration property under running water described in 1. above.

(5) A dry wiper comprising a nonwoven fabric for wiping having the property of disintegrating in flowing water according to the above (1) to (4).

(6) A wet wiper comprising a nonwoven fabric for wiping having the property of disintegrating under running water described in (1) to (4) above.

(7) Fibers containing a cellulose-based natural fiber and a regenerated cellulose fiber having the ability to substantially develop strength by hydrogen bonding are formed into a web by a wet papermaking method, and then placed on a porous support and transferred. The present invention relates to a method for producing a nonwoven fabric for wiping having disintegration in flowing water, which comprises treating the web with a high-pressure water stream to entangle the fibers and performing creping after drying during the drying step.

(8) In the drying step, the web is affixed to a drier having a mirror surface, and the web is peeled off with a blade to perform creping treatment. The present invention relates to a method for producing a nonwoven fabric for use.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a nonwoven fabric for wiping having disintegration property under running water of the present invention will be described in detail.

When a nonwoven fabric for wiping having disintegration property under running water is used as a wet wiper, it is difficult to break (drawing property) when taking out from a container while maintaining good disintegration property in running water, Non-woven fabrics are required to be difficult to be broken (usability). By subjecting the web mainly composed of the specific pulp and the regenerated cellulose fiber to hydroentanglement treatment using a high-pressure water stream, it is possible to obtain a running water disintegrating nonwoven fabric that achieves both a certain strength and disintegration in running water without using a binder. it can. However, with this hydroentanglement treatment alone, there is a problem that the disintegration in running water is deteriorated when an attempt is made to obtain a nonwoven fabric having a sufficient wet strength at the time of removal or use. In addition, the flowing-water-disintegratable nonwoven fabric obtained only by the hydroentanglement treatment has a denser sheet, has a harder texture, and has a poor touch when used.

Therefore, in the present invention, by combining the hydroentanglement treatment with the crepe treatment, the water disintegration is excellent while maintaining the wet strength sufficient for use as compared with the one simply subjected to the hydroentanglement treatment. A high-quality water-disintegrable nonwoven fabric can be obtained. By performing creping, flexibility and volume are imparted, and further combined with the hydroentanglement treatment, and unevenness can be imparted, without lowering these performances, since irregularities are formed in different directions, Even when used in the direction, the wiping properties are good. In addition, since the fibers are entangled with each other, there is a secondary effect that the amount of paper dust generated in the creping process is small.

Further, in the case of a product, even if the product is folded and packaged, a space is formed between the nonwoven fabrics due to unevenness due to the creping process, so that the product can be easily pulled out of the package. When used in a wet state, the web swells due to wetting, and when unevenness is reduced, there is a merit that there is little sticking between nonwoven fabrics, and therefore there is little breakage at the time of drawing.

Here, a description will be given of a phenomenon which is realized by combining the hydroentanglement treatment and the crepe treatment and which has high strength and good running water collapse property. Although it is presumed to be a phenomenon, the reason for excellent water disintegration while maintaining sufficient wet strength is described below. When the hydroentanglement process is performed, the intensity of the entanglement is estimated to be stronger in the front and back layers than in the inside. On the other hand, when creping is performed, it is estimated that buckling occurs inside the nonwoven fabric, and micro-entanglement occurs inside the nonwoven fabric. By the hydroentanglement treatment, the fibers of the web front and back layers are entangled, so that the strength of the nonwoven fabric at the time of drying or wetness is sufficiently expressed, while, by the creping treatment,
It is presumed that the buckling and untangling of the entangled fibers greatly progress inside the nonwoven fabric, which makes little contribution to the strength of the nonwoven fabric, thereby improving the water flow collapse property. In other words, by combining the hydroentanglement treatment and the creping treatment, a decrease in dry strength and wet strength is small, but the fibers swell in running water, and a sheet with a very high disintegration speed is obtained as compared with the case where no creping treatment is performed. It is thought that it is possible.

The crepe ratio of the nonwoven fabric for wiping having disintegration in flowing water of the present invention is preferably 5 to 30%. The crepe rate of the present invention is the difference between the speed of feeding the web before creping and the speed of pulling out the web after the processing divided by the speed before the processing to obtain a percentage. It does not indicate the degree of expansion and contraction of the nonwoven fabric for wiping. When the creping rate is less than 5%, the effect of the creping treatment is small. On the other hand, if it exceeds 30%, the texture becomes harder, which is not preferable. Further, the strength is lowered and the generation of paper dust is increased, which is not preferable.

The form of the crepe of the nonwoven fabric for wiping having disintegration in flowing water according to the present invention, that is, the width of the crepe and the height of the raised crepe are determined as long as the crepe ratio is in the range of 5 to 30%. There is no particular limitation.

Examples of the creping method include wet creping on a press roll in a wet part and dry creping in a cylinder type dryer in a dryer part. The target web is stuck on a press roll or cylinder type dryer, and the web that adheres to the web is separated by a difference between the feed speed of the press roll or cylinder dryer and the web withdrawal speed, and the web is peeled using a doctor blade Then, the web is subjected to a crepe treatment for providing fold-like irregularities. In the present invention, specifically showing an example of the creping process, the web after the hydroentanglement process is applied to a cylinder drier and dried, and when the web is peeled off from the cylinder drier, for the feed speed of the cylinder drier, There is a method of removing the web from the cylinder dryer using a doctor blade by slowing the web withdrawal speed, and this is one of the preferred methods because it can be performed in the same step as drying.

Next, the collapse property of flowing water in the present invention will be described. The term "disintegration in running water" refers to the ease with which the nonwoven fabric is broken down by pouring the nonwoven fabric into running water, being divided by shearing force, and finally reducing the slurry to a certain viscosity (stirring torque) or less. In general, regenerated cellulose fibers with a longer fiber length than natural cellulosic fibers are used, so even if they seem to be fine, the long regenerated cellulose fibers may form flocs again and cause clogging. It is thought that there is. Therefore, it was judged that it was difficult to correctly measure the disintegration in running water by visual judgment.

In the present invention, the evaluation of running water disintegration
"Ease of loosening" as described in section 4.5 of ISP 4501
The evaluation was carried out in accordance with the evaluation method described above. That is, 300 ml of water
A 300 ml beaker containing (20 ° C. ± 5) was placed on a magnetic stirrer, and a rotor (star head, 40φ) was placed.
(× 14 mm) is adjusted to be 600 ± 10 rpm. A test piece of 10 × 10 cm square is put in it, and a stopwatch is pushed. The rotation speed of the stirrer once decreases due to the resistance of the test piece, but increases as the test piece is released. When the number of revolutions has recovered to 540 rpm, the stopwatch is stopped and the time is measured in seconds. The results of the ease of unraveling are indicated by the average value of five tests. The disintegration time of the water-disintegrable nonwoven fabric measured by the above method is desirably 300 seconds or less. If the disintegration time is longer than this level, throwing the nonwoven fabric into the water flow of a flush toilet or the like is likely to cause pipe clogging and the like, which is considered to be a practical problem.

Next, the fibers used in the present invention will be described. A cellulosic natural fiber and a regenerated cellulose fiber having the ability to substantially develop strength by hydrogen bonding are used.
Cellulose-based natural fibers that exhibit strength substantially through hydrogen bonding (hereinafter, simply referred to as cellulosic-natural fibers) refer to webs before entanglement that have wet strength due to the surface tension of water between fibers when wet. A fiber that has the ability to develop strength due to hydrogen bonding between hydroxyl groups of cellulose when dried and depleted of water. Only a fiber that does not have the strength-developing ability by hydrogen bonding can only exhibit strength by entanglement or adhesion, and cannot impart disintegration in flowing water when the strength is imparted. Although it has a disintegration property by itself, its practical strength is poor, and it is necessary to use it in combination with a wet strength agent and a dry strength agent. Specifically, the cellulosic natural fiber used in the present invention is a woody pulp such as coniferous or hardwood wood pulp and bamboo pulp, a herbaceous pulp such as bagasse, kenaf, straw pulp, esparto, hemp pulp and cotton pulp. ,
Pulp made of bast fibers such as mulberry, mitsumata, etc., each of which becomes a wet web and develops strength when dried.
Wood pulp is the most preferred cellulosic natural fiber because of its availability, economy and quality stability. Among wood pulp, unbleached or bleached chemical pulp obtained by digesting softwood or hardwood by a kraft method, a soda method, a polysulfite method, or the like is preferable because of its good feel and texture. Further, in order to soften the feel of the nonwoven fabric and to reduce the loss of fibers at the time of confounding, the Canadian standard freeness is set at 40%.
It is preferably 0 ml CSF or more. Naturally, besides the cellulosic natural fibers and regenerated cellulose fibers, a small amount of other shaped substances such as fibers and liquid binders other than those limited by the present invention within the range not impairing the performance of the nonwoven fabric of the present invention are contained in the nonwoven fabric. Is possible.

The regenerated cellulose fiber used in the present invention will be described. The regenerated cellulose fibers used in the present invention are those obtained by dissolving cellulose raw materials such as wood pulp and cotton linter in a solvent and regenerating them as fibers in a spinning bath.Specifically, alkali cellulose is dissolved in carbon disulfide. Viscose, viscose rayon obtained by regenerating and spinning in dilute sulfuric acid, dissolving cellulose in copper ammonia solution, and regenerating and spinning in sulfuric acid solution copper ammonia rayon (cupra), Alternatively, a solvent-spun rayon (lyocell) obtained by dissolving cellulose in N-methylmorpholine-N-oxide and spinning in water is exemplified.

The fineness of the regenerated cellulose fiber is 0.11 to
A range of 6.7 decitex is preferable, and more preferably 0.33 to 2.2 decitex. Fineness is 0.1
If it is less than 1 dtex, the nonwoven fabric for wiping becomes dense,
The volume feeling is reduced, and the handleability is reduced. When the fineness exceeds 6.7 decitex, the nonwoven fabric for wiping becomes hard, and the texture and the feeling of wiping are reduced.

The fiber length of the regenerated cellulose fiber is 2 to 12
mm is preferable, and more preferably 3 to 10 mm
It is. If the fiber length is less than 2 mm, the entanglement is weak and the wet strength of the nonwoven fabric is weak, and the application is limited. However, the pickup property of the entangled web from the support is further deteriorated, and the formation of the nonwoven fabric is hindered. When the fiber length is long, flocs are formed in the web, and the strength of entanglement is formed, and a portion that is easily and easily collapsed by running water is formed.
Even if the confounding becomes strong, it is possible to produce a non-woven fabric that can be broken down under running water because it can be selectively broken down from the portion that easily breaks down.However, once the fiber length exceeds 12 mm, the fibers that have collapsed once become entangled again in running water. Large lumps occur, that is, the collapse of flowing water decreases.

The content of the regenerated cellulose fiber of the present invention is preferably from 5 to 70% by mass. When the amount is less than 5% by mass, the strength of the wet paper web is reduced, so that the use is limited. However, it is more difficult to pick up the entangled web from the support, which hinders stable production. If the content exceeds 70% by mass, a large pressure is required for the entanglement of the regenerated cellulose fibers. If the regenerated cellulose is entangled so that the fibers do not fall off, disintegration in running water is inhibited.

The basis weight of the nonwoven fabric for wiping having disintegration in flowing water of the present invention is preferably from ²⁰ to 150 g / m ² . 20g /
If it is less than m ² , practical strength cannot be obtained with single paper. Further, it is difficult to pick up the web from the support after the entanglement treatment. If it exceeds 150 g / m ² , when the same entanglement energy is applied to the web, the impact of the water stream on the surface becomes strong, so that the running water disintegration is inferior.

Next, an example of the method for producing the nonwoven fabric for wiping of the present invention will be described in detail. First, a group of fibers containing a cellulosic natural fiber and a regenerated cellulose fiber having substantially the ability to develop strength by hydrogen bonding is put into water, stirred, disintegrated and dispersed into a single fiber to form a slurry. The slurry is formed into a web by a wet papermaking method using a paper machine such as a round paper machine, a short net paper machine, an inclined wire paper machine, a fourdrinier paper machine, or a composite paper machine thereof.

Next, the obtained web is jetted with a high-pressure water stream onto the web being conveyed on the porous support, and the fibers are entangled. The porous support is a wire made of a metal such as stainless steel or bronze or a plastic material such as reinforced polyester or polyamide in a weave method such as plain weave or twill weave, and preferably about 10 to 250 mesh. Alternatively, a porous plate obtained by punching a metal plate and corresponding to the number of meshes of the above-mentioned wire is preferable. High-pressure water flow is 5 to 150 Pascal (P
At the water pressure of a), pores of about 50 μm to 300 μm are jetted from the nozzles arranged in a single row or multiple rows onto the surface of the web, and preferably have a columnar shape. The interval between the pores is preferably about 0.3 to 2 mm. The degree of entanglement under these conditions depends on the basis weight, formulation,
Since it depends on factors such as the web transport speed, the diameter of the water flow, the interval thereof, and the number of confounds, it is necessary to find the optimal conditions under which the strength and the disintegration of the flowing water are expressed in a well-balanced manner.

After the confounding is performed, creping treatment is performed during or after the drying step to form irregularities, thereby obtaining the nonwoven fabric for wiping of the present invention. The drying process is performed with a dryer having a mirror surface,
The creping process can be performed by attaching the web to the dryer and stripping the web with a blade, so that the nonwoven fabric for wiping having disintegration property under running water, which is the object of the present invention, can be manufactured more easily.

According to the present invention, two or more webs after the hydroentanglement are stacked and attached to a dryer, and the overlapped webs are subjected to creping treatment to form irregularities, thereby obtaining the nonwoven fabric for wiping of the present invention. You can also. Alternatively, two or more webs obtained by wet papermaking may be superposed and subjected to hydroentanglement, then attached to a drier, and creped by stripping the web with a blade.

The nonwoven fabric for wiping having disintegration in flowing water of the present invention effectively functions as a dry wiper or a wet wiper.

[0044]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to the examples. The percentages described in the examples and comparative examples are all based on mass.

Next, a method for measuring physical properties according to the present invention will be described. 1. Weight was measured according to the method described in JIS L 1096. 2. A sample under the same conditions as the tensile strength 1 was used. 20mm width, 150m length
m sample, span 100 mm, speed 200 mm / mi
When pulled with n, the maximum load until the sample was broken was measured using Tensilon HTM-100 (manufactured by Orientec) in the vertical direction (web transport direction) and the horizontal direction (vertical orthogonal direction). And the average value of each of the five measurements. 3. Flowing water disintegration JIS P 4501 The evaluation was carried out in accordance with the evaluation method of “easiness of loosening” described in section 4.5. That is, water 300
ml (20 ° C. ± 5) into a magnetic stirrer and place the rotor (star head, 4).
It is adjusted so that the number of revolutions (0φ × 14 mm) is 600 ± 10 rpm. A test piece of 10 × 10 cm square is put in it, and a stopwatch is pushed. The rotation speed of the stirrer once decreases due to the resistance of the test piece, but increases as the test piece is released. When the number of revolutions has recovered to 540 rpm, the stopwatch is stopped and the time is measured in seconds. For the result of unraveling, test 5
It was shown as the average value of the number of times performed. A disintegration time of 300 seconds or less measured by the above method was regarded as a pass. If the disintegration time is at this level, it will be difficult to cause clogging of the pipe even when it is put into a water flow such as a flush toilet, and it can be determined that there is no practical problem. In general, regenerated cellulose fibers with a longer fiber length than natural cellulosic fibers are used, so even if they seem to be fine, the long regenerated cellulose fibers may form flocs again and cause clogging. It is thought that there is. Therefore, it was judged that it was difficult to correctly measure the disintegration in running water by visual judgment. 4. Tactile sensation The touch of the nonwoven fabric was evaluated on a four-point scale of ◎ very good, 良 い good, △ normal, and × bad. 5. Dropping of paper dust (during drying) The presence or absence of dropping of paper dust during use was investigated. The case where the nonwoven fabric was hit and paper powder was hardly dropped was evaluated as ◎, the case where it was slightly observed was evaluated as △, and the case where paper powder was largely dropped was evaluated as x. 6. Dropping of paper dust (during creping) The presence or absence of dropping of paper dust during creping was investigated. In the composition of the present invention, the paper powder which had not been subjected to the hydroentanglement processing was subjected to creping, and the falling off of the paper powder was evaluated as △. 7. Dropping of paper dust (when wet) Dropping of paper dust when wet was investigated. When the body surface was strongly rubbed, ◎ indicates that the paper powder had good wiping properties and no paper dust was left, △ indicates that a small amount of paper was left, and X indicates that the substance adhered a lot. 8. Take-out property As a study of the pull-out property from the package when wet, 15 × 1
Fold the 9 cm sheet, put 10 sheets as a set, put the back side in a polyethylene bag coated with aluminum vapor, and after evenly including water twice the mass of the nonwoven fabric, degas and apply heat sealing. , Prototype of pocket-type wet tissue. The surface of the bag was cut out, and the state of pulling out the nonwoven fabric from the bag was investigated. ◎ is good, △
Is torn when pulled strongly, and x is torn.

Examples 1 to 4 Fineness 0.77 dtex, fiber length 7 mm
Rayon fiber 20% and softwood bleached kraft pulp (NB
A slurry of 80% (KP, Canadian standard freeness 500 ml) was prepared, and a wet state web having a moisture content of about 500% was formed on a paper machine so that the absolute dry mass was 55 g / m ² . Next, a high-pressure columnar water stream was jetted from the nozzle having a pore diameter of 100 μm and an interval of 0.6 mm at a water pressure of 25 Pa onto the web on the 76-mesh plain woven plastic wire at a conveying speed of 30 m / min. After drying with a cylinder dryer to almost dry condition, crepe rate 5%
Then, dry creping treatment was performed to obtain a nonwoven fabric for wiping of the present invention. Further, the crepe rate was 10% (Example 2),
% (Example 3) and 30% (Example 4) were obtained.

Comparative Example 1 A nonwoven fabric for wiping was obtained in the same manner as in Example 2 except that the creping treatment was not performed.

Comparative Example 2 An attempt was made to obtain a nonwoven fabric for wiping in the same manner as in Example 2 except that only NBKP of Examples 1 to 4 was used. However, a web could be obtained without being able to pick up from a wire. After that, the web was obtained by reducing the hydroentanglement pressure to 5 Pa.

Comparative Example 3 An attempt was made to obtain a nonwoven fabric for wiping in the same manner as in Example 2 except that only the rayon fibers of Examples 1 to 4 were used. Since the paper powder fell off), the water pressure for the confounding was raised to 75 Pa to obtain a nonwoven fabric for wiping.

Comparative Example 4 A nonwoven fabric for wiping was obtained in the same manner as in Example 2 except that the hydroentanglement treatment was not performed.

Example 5 A rayon fiber having a fineness of 0.55 decitex and a fiber length of 5 mm was 10%, and the NBKP used in Examples 1 to 4 was 95%.
A nonwoven fabric for wiping was obtained in the same manner as in Example 2 except that the confounding pressure was 25 Pa.

Example 6 Wiping was performed in the same manner as in Example 2 except that 50% of rayon fiber having a fineness of 1.67 decitex and a fiber length of 10 mm was used, the NBKP used in Examples 1 to 4 was 50%, and the confounding pressure was 40 Pa. A non-woven fabric was obtained.

Example 7 Dry creping was carried out using a microcreper manufactured by Micrex Corporation in the United States. The conditions are speed 25m / min, temperature 63 ° C, pressing pressure 60psi,
The blade shape was flat and the compression ratio was 20%.

Table 1 shows the results of Examples 1 to 7 and Comparative Examples 1 to 4.

[0055]

[Table 1]

From Table 1, it can be seen that the nonwoven fabric for wiping having disintegration in flowing water of the present invention is excellent in tactile sensation and handleability, excellent in disintegration in flowing water, and excellent as a dry wiper. In Comparative Example 1, the one not subjected to the creping treatment has a poor touch feeling. Also, the disintegration was inferior to the creped one. Comparative Examples 2 and 3 show that only cellulose-based natural fibers or regenerated cellulose fibers alone have excellent properties such as tactile sensation and disintegration, but it is difficult to achieve practical performance without excess or deficiency. In the case of Comparative Example 4 which was not subjected to the hydroentanglement process, paper powder was often dropped during use, and it was difficult to use as a wiper.

Examples 8 to 14 Each of the wiped nonwoven fabrics used in Examples 1 to 7 was impregnated with a size press so that pure water adhered thereto at about 100 g / m ² . A wiped nonwoven was obtained.

Comparative Examples 5 to 8 Each of the wiping nonwoven fabrics used in Comparative Examples 1 to 4 was impregnated with a size press so that pure water adhered thereto at about 100 g / m ² . A wiped nonwoven was obtained.

Comparative Example 9 A commercially available wet wiper type baby butt wipe was purchased, and the wet tensile strength, running water disintegration property, tactile sensation and removal property were evaluated. Comparative Example 9 was made of softwood pulp and rayon fiber, and had a wet basis weight of 161.2 g.
/ M ² , a thickness of 0.3 mm, and a wiped nonwoven fabric obtained only by the hydroentanglement treatment.

The results of Examples 8 to 14 and Comparative Examples 5 to 9 are shown in Table 2.

[0061]

[Table 2]

From Table 2, it can be seen that the nonwoven fabric for wiping having disintegration in flowing water of the present invention has sufficient wet strength to be used, is excellent in tactile sensation and handling properties, and is excellent in disintegrating properties in flowing water. . The non-creped product of Comparative Example 5 has a sufficient wet strength, but has a poor touch feeling and takeout property. Also, the disintegration was inferior to the creped one. Comparative Example 6 is composed of only cellulosic natural fibers, and shows good running water disintegration, but it is found that the feel and the performance at the time of taking out are inferior.
Comparative Example 7 was composed of only regenerated cellulose fibers,
It can be seen that the feel, paper powder and takeout properties are good, but there is no disintegration. In Comparative Example 8 which was not subjected to hydroentanglement processing, the wet strength was weak, and the paper powder was often dropped during use, making it difficult to use as a wiper. Further, it can be seen that the nonwoven fabric for wiping of the present invention is superior in water flow disintegration, tactile sensation, and take-out performance as compared with commercial products.

[0063]

The present invention is directed to a nonwoven fabric for wiping which is collapsible and integrated with a web containing regenerated cellulose fibers and a cellulosic natural fiber having an ability to substantially develop strength by hydrogen bonding. There, high pressure water flow treatment to suppress the falling off of the fiber and express the strength, while suppressing the collapse of the nonwoven fabric during still water or wiping, imparting flexibility, volume by creping, and further imparting irregularities, An object of the present invention is to provide a nonwoven fabric for wiping which has improved wiping properties and has improved running water disintegration properties with improved running water disintegration properties without deteriorating the performance.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) D21H 27/22 D21H 27/22 // A47K 7/00 A47K 7/00 C

Claims (8)

[Claims] The present invention relates to a nonwoven fabric for wiping having a flow-through disintegration property in which a web containing cellulosic natural fibers and a regenerated cellulosic fiber having substantially the strength expressing strength by hydrogen bonding are entangled by a high-pressure water stream. A nonwoven fabric for wiping, which has running water disintegration properties in which irregularities are formed by creping. 2. A crepe ratio of 5 to 30%.
A nonwoven fabric for wiping having the disintegration property of flowing water according to the above. 3. The disintegration time of the nonwoven fabric for wiping measured in accordance with the evaluation method for ease of loosening described in 4.5 of JIS P 4501 is 300 seconds or less. The nonwoven fabric for wiping according to any one of the preceding claims. 4. The nonwoven fabric for wiping according to claim 1, wherein the natural cellulose fiber is wood pulp. 5. A dry wiper comprising the nonwoven fabric for wiping having the property of disintegrating in flowing water according to claim 1. 6. A wet wiper comprising the nonwoven fabric for wiping having the property of disintegrating in flowing water according to claim 1. 7. A web comprising a cellulosic natural fiber and a fiber containing a regenerated cellulose fiber having substantially the ability to develop strength by hydrogen bonding formed into a web by a wet papermaking method, and then placed on a porous support. A method for producing a nonwoven fabric for wiping having disintegration in flowing water, comprising treating the web with a high-pressure water stream, entangled with fibers, and performing creping after drying during the drying step. 8. The nonwoven fabric for wiping having disintegration in flowing water according to claim 7, wherein in the drying step, the web is affixed to a drier having a mirror surface, and the web is peeled off with a blade to be creped. Production method.