Patent Grant
7943538
This application claims priority of Japanese Patent Application No. 2005-141414, filed May 13, 2005, which is hereby incorporated by reference in its entirety.
1. Field of the Invention
The present invention relates to a water-decomposable cleaning product which is used to remove dirt in a place where water is used, such as in a flush toilet and which can be discarded into water after the use thereof, and a production method thereof.
2. Description of the Related Art
Japanese Patent Application Laid-Open No. Showa 62(1987)-186833 (JP62-186833) discloses a disposable toilet cleaning brush used for cleaning a flush toilet.
The toilet cleaning brush is produced using a paper comprising: i) staple fibers of a ligneous pulp and ii) a binder, such as CMC (carboxymethyl cellulose), by a method in which plural cuts are formed in the paper and the paper is wound to form a brush. The toilet cleaning brush is fixed to a head of the paper-made handhold of the brush. After the bowl is wiped with the toilet cleaning brush, the cleaning brush and the handhold together are discarded into a flush toilet and are decomposed in water. It is also described that for controlling the time needed for the dissolution of the paper in water, the surface of the brush is subjected to a wax treatment.
The JP62-186833 describes that since the time needed for cleaning a toilet bowl is such a short time as between 10 seconds and 20 seconds, before the paper constituting the toilet cleaning brush is dissolved in water, the cleaning can be accomplished.
However, the toilet cleaning brush produced with the paper itself which is produced by fixing ligneous pulp fibers through a water-soluble CMC is swollen at the contact thereof with water during the cleaning of a toilet bowl and the strength thereof is extremely lowered, so that it becomes difficult to wipe off the dirt adhered to the bowl by such a brush. With respect to the brush which has been subjected to a wax treatment, since a wax component may suppress the decomposition of the paper in water, it takes a long time until the brush has been decomposed in a purification tank or the like.
The present invention solves the above-noted problem accompanying the conventional arts.
It is therefore an object of the present invention to provide a water-decomposable cleaning product which can effectively wipe off the dirt adhered to the bowl of a flush toilet or the like, and a production method thereof.
It is another object of the present invention to provide a water-decomposable cleaning product which not only has a high strength when the cleaning product scrubs a toilet bowl or the like and can exhibit the effect of removing the dirt, but also can be dispersed in water within a relatively short time after the use thereof; and the production method thereof.
According to a first aspect of the present invention, there is provided a water-decomposable cleaning product dispersible in water, includes: a cleaning part, at least a part of the cleaning part including a water-decomposable fiber-interlacing nonwoven fabric; and a holding part.
According to a second aspect of the present invention, there is provided a production method of a water-decomposable cleaning product, comprising: forming a string by twining a fiber-interlacing nonwoven fabric; and arranging the plural strings in a cleaning part and adhering at least a part of the strings to each other.
According to a third aspect of the present invention, there is provided a production method of a water-decomposable cleaning product, comprising: superimposing a fiber-interlacing nonwoven fabric and a water-decomposable paper which includes cellulose fibers; forming a string by twining the fiber-interlacing nonwoven fabric and the water-decomposable paper together; and arranging the plural strings in a cleaning part and adhering at least a part of the strings to each other.
According to a fourth aspect of the present invention, there is provided a production method of a water-decomposable cleaning product, comprising: twining a water-decomposable paper including cellulose fibers; winding a fiber-interlacing nonwoven fabric around the twined water-decomposable paper; and arranging plural strings in a cleaning part and adhering at least a part of the strings to each other.
As shown in
In
A torsion spring (not illustrated) is attached to the pivot 15 and by the torsion spring, the lever 14 is biased in the clockwise direction around the pivot 15 as the fulcrum, so that the pressing part 13 is biased in the direction approaching the holding part 12. A handle part (not illustrated) is provided in the upper part of the handhold part 11 and an operating lever (not illustrated) is provided in the handle part (not illustrated). The upper terminal of the operating wire 16 which is a thick wire is connected to the operating lever. When the operating lever (not illustrated) is pulled up, the pressing part 13 is spaced apart from the holding part 12. At this time, when the holding part 2 of the cleaning product 1 is inserted between the holding part 12 and the pressing part 13 and the operating lever (not illustrated) is released from the hand, by the bias force of the torsion spring (not illustrated), the holding part 2 of the cleaning product 1 is supported between the holding part 12 and the pressing part 13.
By scrubbing the part to be cleaned (such as a toilet bowl or the like) with the cleaning part 3 of the cleaning product 1 while holding the holder 10 with the cleaning product 1, the dirt adhered to the surface of the bowl or the like can be removed. At this time, it is also possible that the cleaning part 3 is wetted by the water standing in the bowl, and the bowl is wiped by the wetted cleaning part 3. After the completion of the cleaning, by discharging the pressing force of the pressing part 13 through pulling up the operating lever, the cleaning product 1 can be discarded into the bowl without touching the cleaning product 1 by the hand.
As shown in
The twined string 4X shown in
The fiber-interlacing nonwoven fabric comprises i) fibers having a fiber length of, for example, 20 mm or less which fibers can be interlaced by the water-jet treatment, and ii) pulp fibers which are natural fibers. When the nonwoven fabric comprises pulp fibers and fibers having a fiber length of 20 mm or less which can be interlaced, by a water-jet treatment, not only are the fibers other than the pulp fibers interlaced, but the pulp fibers are also hydrogen-bonded to each other and to the other fibers which can be interlaced. This fiber-interlacing nonwoven fabric can maintain a high dry strength thereof through the hydrogen bond force of the pulp fibers and can maintain a high wet surface strength thereof through the interlacing force between the fibers. When the cleaning product is discarded into water and contacts a lot of water, due to the separation of the individual pulp fibers from each other, the twine of the string is loosened and the interlacing force of the fibers which can be interlaced is loosened, so that the individual fibers are separated from each other within a relatively short time.
As the other fibers which have a fiber length of 20 mm or less and can be interlaced by the water-jet treatment, biodegradable fibers are preferably used. Preferred examples of the biodegradable fibers include regenerated cellulose fibers, such as viscose rayon fibers, solvent spinning rayon fibers, polynosic rayon fibers, copper-ammonia rayon fibers and alginate rayon fibers. Examples of the other fibers which have a fiber length of 20 mm or less and can be interlaced by a water-jet treatment include synthetic resin fibers, such as polyethylene terephthalate (PET) fibers, nylon fibers and polypropylene (PP) fibers.
Examples of the fibers which may be used either in combination with the pulp fibers or instead of the pulp fibers include natural fibers, such as hemp, cotton, bagasse, banana, pineapple and bamboo.
Further, i) fibers of polyvinyl alcohol (PVA) which is a water-soluble resin and ii) water-soluble or water-swellable carboxyl methyl cellulose (CMC) may be added as a binder into the composition of the fiber-interlacing nonwoven fabric for enhancing the dry strength of the water-decomposable sheet 8, or such a binder may be added to the twined string 4X which has been formed, for easier maintaining of the twined form of the string.
In place of the above pulp fiber or in combination with the above pulp fiber, a fiber-interlacing nonwoven fabric produced by the following method can be also used:
1) preparing fibrillated rayon fibers in such a manner that, in the surfaces of the fibers, a lot of microfibers having a fiber length of 1 mm or less are peel-formed by beating the rayon fibers having a fiber length of from 3 mm to 7 mm,
2) papermaking, in a wet system, one of the following i) and ii):
3) then, subjecting the resultant fibers to a water-jet treatment.
Since in this nonwoven fabric, the fibers are tightly fixed to each other through the hydrogen bond force of the fibrillated rayon fibers, the dry strength and the wet strength of this nonwoven fabric can be enhanced, and when the cleaning product contacts a lot of water, the fibrillated rayon fibers are dispersed, so that the cleaning product can be water-decomposed within a short time.
The fiber-interlacing nonwoven fabric constituting the twined string 4X comprises i) preferably 10% by mass or more of natural fibers, such as pulp fibers and ii) 10% by mass or more of fibers such as rayon fibers having a fiber length of 20 mm or less and interlaceable by a water-jet treatment. By comprising 10% by mass or more of natural fibers, the dry strength of the water-decomposable sheet 8 can be enhanced and the twined form of the twined string 4X after strongly twining can be maintained through the hydrogen bond force of the fibers. Further, by comprising 10% by mass or more of the fibers which can be interlaced, the wet strength of the water-decomposable sheet 8 can be enhanced.
The water-decomposable sheet 8 comprising a fiber-interlacing nonwoven fabric has a weight per square-meter of preferably 30 g/m2 or more, more preferably 50 g/m2 or more and a thickness of preferably from 0.1 mm to 0.5 mm. When the weight per square-meter is less than 30 g/m2, not only the wet strength of the water-decomposable sheet 8, but also the strength of the string 4 is lowered. The upper limit of the weight per square-meter is not particularly defined; however, so that the time needed for the water-decomposable sheet 8 to decompose in water is 700 sec or less, the upper limit of the weight per square-meter is preferably about 120 g/m2.
In
The twined string 4Y shown in
By twining together the water-decomposable sheet 8 and the water-decomposable paper 9 which are superimposed, the superimposed sheets can be strongly and tightly twisted and twined because of a high strength of the water-decomposable sheet 8 comprising a fiber-interlacing nonwoven fabric. After the twining, the twined string can maintain the form thereof obtained through the twining in a dry state, due to the hydrogen bond force of the fibers constituting the water-decomposable paper 9. Accordingly, the twined string 4Y having a high density can be easily processed and can maintain the twined form thereof. By forming the string 4 of the cleaning product 1 shown in
In the twined string 4Y shown in
In the forming of the twined string 4Y shown in
The twined string 4Z shown in
The number of twining times for forming each of the twined string 4X, the twined string 4Y and the twined string 4Z is preferably from 4 times to 30 times per 25 cm of the water-decomposable sheet constituting the twined string. When the twining times are less than 4 times, the density of the twined string becomes too low, so that the string cannot bear a frictional force during the wiping of the dirt and is easily broken. On the other hand, when the twining times are more than 30 times, a load is charged to the water-decomposable sheet during the twining thereof, so that it is feared that the sheet is cut. The thickness of the twined string 4X, the twined string 4Y and the twined string 4Z is preferably in the range of from 1 mm to 10 mm. When the thickness is in this range, i) the touch of the string 4 wiping the part to be cleaned is preferable, and ii) when the cleaning product is discarded into a flush toilet, the piping is not clogged by the cleaning product, so that the cleaning product can be easily discarded.
The string 4 constituting the cleaning product 1 shown in
Since during the use of the cleaning product 1, the holding part 2 of the cleaning product 1 is held between the holding part 12 and the pressing part 13 of the holder 10 shown in
The cleaning part 3 may be formed by adhering the strings 4 to each other through a water-soluble adhesive or by bonding the strings 4 to each other through the hydrogen bond force between the strings. In this case, when a toilet bowl or the like is wiped by the cleaning part 3 and the cleaning part 3 contacts water, individual strings 4 can move independently and the wiping is performed by the individual independent strings 4.
When the fixing force between the strings 4 in the holding part 2 is weakened, the water-decomposition time in which the strings 4 are separated from each other in the cleaning part 2 becomes shorter than the water-decomposition time in which the string 4 itself is water-decomposed into individual fibers. When the cleaning product 1 is discarded into a flush toilet or the like and contacts a lot of water, immediately, the adhering force between the strings 4 in the holding part 2 is discharged and the strings 4 are separated into individual strings 4, and thereafter, the individual strings 4 can be water-decomposed within a short time.
The time needed for the water-decomposition of the individual strings 4 is preferably 700 sec or less, more preferably 600 sec or less, still more preferably 300 sec or less, in terms of the value measured according to JIS P4501 (relaxability test for the toilet paper), based on 100 mm of the length of one piece of the string 4. This is a measurement from i) a time when the string 4 is charged into 300 mL of an ion-exchanged water having a temperature of 20±5° C. which is placed in a 300 mL beaker, and then the string 4 and the ion-exchanged water together are stirred by rotating a rotator at a speed of 600 rpm in the ion-exchanged water, to ii) a time when the form of the string has disappeared and the form of the sheet has not remained, so that individual fibers have been dispersed.
Next, with respect to the method of using the cleaning product 1, explanations are given.
While holding the holding part 2 of the cleaning product 1 shown in
After the cleaning is accomplished, when the pressing part 13 of the holder 10 is parted from the holding part 12, the cleaning product 1 is dropped into a flush toilet and the cleaning product 1 can be flushed away together with a flush water. Since in water, the fixing force of the holding part 2 is discharged and individual strings 4 are dispersed, the piping is not clogged by the strings 4 and the flush water can flow. Thereafter, in the piping or in a digestion tank, the string 4 is decomposed into individual fibers.
The cleaning product 21 shown in
In the cleaning product 21, the individual strings 4 may be not adhered to each other. By winding the bundle of the strings 4 with the holding material 5, the cleaning product 21 can maintain the form thereof shown in
The cleaning product 31 shown in
In the cleaning product 31, since the folded parts 4b of the strings 4 are located in the cleaning part 33 and no cut end face 4a of the strings 4 is exposed in the cleaning part 33, even when the head of the cleaning part 33 contacts water and the folded parts 4b are wetted by water, the twine of the string 4 is unlikely to be loosened and the stiffness of the string 4 can be maintained for a relatively long time. Therefore, the removal of the dirt adhered to the part to be cleaned by scrubbing with the folded part 4b can be easily performed.
The cleaning product 41 shown in
In the cleaning product 51 shown in
When the cleaning product 51 is discarded into a flush toilet after the use thereof, the sheet pulp can be decomposed into individual pulp fibers within a relatively short time.
In the cleaning product 51 shown in
The cleaning product 61 shown in
The water-decomposable block 7 comprises water-dispersible and biodegradable fibers, such as pulp fibers. The water-decomposable block 7 is produced, for example by molding pulp fibers into a three-dimensional form. The production method thereof comprises: a step of dispersing the pulp fibers in water; a step of feeding the dispersion of the pulp-fibers into a concave-shaped mold which is prepared for molding a product in a cylindrical form and in which a porous part for draining is formed at the bottom of the mold; a step of dehydrating the molded article; and a step of drying the molded article by heating. The step of feeding the pulp-fibers dispersion and the step of dehydrating the molded article in the above-noted production method may be replaced by a step of feeding the dispersion of the pulp-fibers into the above-noted mold or into a mold in another form for compression and a step of compressing the molded article by pressurization using a pressing machine after or while dehydrating the molded article. Still another production method of the water-decomposable block 7 comprises: a step of preparing a raw material in a sludge form by mixing pulp fibers, a thickener and a water-soluble adhesive; a step of extrusion-molding the above-prepared raw material using a screw extruder; a step of dehydrating the molded article; and drying the molded article by heating.
In the water-decomposable block 7, the aggregated pulp fibers or the aggregated other fibers are fixed to each other through hydrogen bonding or are adhered to each other by a water-soluble adhesive.
In the cleaning product 61 shown in
In the cleaning product 61 shown in
The water-decomposable cleaning product 71 comprises the holding part 72 and the cleaning part 73. The cleaning product 71 comprises at least one cleaning unit 78. According to the third embodiment shown in
The plural compressed-fiber sheets 76 which are piled up are held in the outer sheet 75. The compressed-fiber sheet 76 is produced by laminating water-dispersible fibers having a fiber length of 20 mm or less and by compressing the laminated fibers. Examples of the fibers used for the production of the compressed-fiber sheet 76 include natural fibers, such as pulp fibers and regenerated cellulose fibers, such as rayon fibers. The compressed-fiber sheet 76 in a compressed state can maintain the form of a sheet through the hydrogen bond force of the cellulose fibers and the mechanical bond force between the fibers which is generated by compression. It is also possible that the fibers are connected to each other by a water-soluble adhesive. In this case, the compressed-fiber sheet 76 may comprise synthetic resin fibers, such as PET fibers, PP fibers, PE fibers and nylon fibers. However, the compressed-fiber sheet 76 comprises preferably only biodegradable fibers.
For example, the compressed-fiber sheet 76 comprises only pulp fibers. The pressure used for the compression by which the compressed-fiber structure 76 is produced is 2,000 kPa to 6,000 kPa, for example, 3920 kPa (40 kgf/cm2) and the time for the compression is from 1 sec to 5 sec. The compression is performed at normal temperature and may be performed during heating. For enhancing the hydrogen bond force between the fibers, the fibers may be heated and compressed after water is added to the fibers by the spraying.
Since the compressed-fiber sheet 76 comprises fibers having a fiber length of 20 mm or less, preferably pulp fibers, when the cleaning product 71 is discarded into a flush toilet or the like, the compressed-fiber sheet 76 can be decomposed into individual fibers within a relatively short time. Therefore, the size of the compressed-fiber sheet 76 can be set optionally according to the form of the cleaning product. However, for decomposing the compressed-fiber sheet 76 in water within a short time, it is preferred that when the compressed-fiber sheet 76 contains three times its own weight in water, the compressed-fiber sheet 76 is swollen to at least twice its normal volume. The time needed for the water-decomposition of the compressed-fiber sheet 76 (a measuring method thereof is noted above) is preferably 700 sec or less, more preferably 600 sec or less, still more preferably 300 sec or less. The mass of the compressed-fiber sheet 76 used for the production of one cleaning product 71 is preferably 20 g or less in total. 20 g corresponds to the weight of a toilet paper having a length of 9 m and is in the range where the clogging of the piping is unlikely to be caused in a normal flush toilet.
The compressed-fiber sheet 76 may comprise a cleaning agent, an abrasive, an antimicrobial agent or a perfume.
As shown in
The cleaning product 71 shown in
The cleaning product 71 is held by a holder in such a manner that the holding part 72 of the cleaning product 71 is supported by the holder. A holder holding the cleaning product 71 is different from the holder 10 shown in
Since the holding material 74 comprises a water-decomposable paper produced by papermaking pulp fibers or by papermaking pulp fibers and by adhering fibers to each other through a water-soluble adhesive, when the cleaning product 71 is discarded into water after the use thereof, the holding force of the holding material 74 is immediately discharged and the adhered cleaning units 78 are separated into two cleaning units 78. Further, in water, the adhesion between the edge parts 75a of the outer sheet 75 and between the edge parts 75b of the outer sheet 75 is discharged, and the outer sheet 75 and the compressed-fiber sheet 76 are separated from each other, so that the outer sheet 75 and the compressed-fiber sheet 76 are independently decomposed into individual fibers.
The cleaning product 91 shown in
In winding the water-decomposable sheet 94, by applying a water-soluble adhesive to a surface of the water-decomposable sheet 94, the layers of the water-decomposable sheet 94 may be adhered to each other layer by layer while winding the water-decomposable sheet 94. Otherwise, after the water-decomposable sheet 94 has been wound into a columnar form, the wound water-decomposable sheet 94 may be compressed partially, for example in the form of dots to hydrogen-bond the layers of the water-decomposable sheet 94 partially. Further, the whole of the wound water-decomposable sheet 94 into a columnar form may be compressed to produce the cleaning product 91. Further, the water-decomposable sheet 94 comprising a fiber-interlacing nonwoven fabric and the water-decomposable paper 9 shown in
The holding part 92 is supported between the holding part 12 and the pressing part 13 of the holder 10 shown in
When the cleaning product 91 is discarded into a flush toilet after the cleaning, the holding part 5 comprising a water-decomposable paper or the like is peeled and the winding of the water-decomposable sheet 94 in a columnar form is loosened, followed by the decomposition of the water-decomposable sheet 94 in water.
The interface parts between the above-noted layers of the wound water-decomposable sheet 94 may comprise a cleaning agent, an abrasive, an antimicrobial agent or a perfume.
The cleaning product 101 shown in
With respect to the cleaning product 101 shown in
The water-decomposable cleaning product 111 shown in
With respect to the cleaning product 111, the holding part 5 is held by a holder, and the part to be cleaned, such as the surface of a toilet bowl or the like is cleaned by the cleaning part 113 comprising the water-decomposable sheet 94, which comprises a fiber-interlacing nonwoven fabric. In this case, a holder in which the holding part 12 and the pressing part 13 shown in
In the production of the cleaning product 111 shown in
When the outer sheet 75 shown in
The cleaning product 121 is produced by bundling-up the strings 4 which are folded into halves. The strings 4 are the same as those shown in
Since in the cleaning product 121, the strings 4 are not separated from each other in a dry state, the cleaning product 121 can maintain the product form thereof in a dry state. In this case, as the holder, a holder in which the holding part 12 and the pressing part 13 shown in
In the cleaning products according to the above-noted other embodiments, only the holding part or both the holding part and the cleaning part may be compressed.
As shown in the following Table 1, fiber-interlacing nonwoven fabrics have been prepared in Examples 1 to 5. Further, the twined strings 4X shown in
The fiber-interlacing nonwoven fabrics of Examples 1 to 5 were prepared by a method in which fiber webs were papermade on a porous plastic wire and without drying fiber webs, fibers were interlaced by applying a jet stream to the fiber webs using a high-pressure waterjet injecting apparatus. The high-pressure waterjet injecting apparatus in which one nozzle has an opening diameter of 95 μm and 2,000 nozzles are lined up with a pitch of 0.5 mm in the cross direction which crosses the machine direction of the fiber webs orthogonally, was used. While conveying the fiber webs with a speed of 30 m/min, a treating energy per an area unit of 0.24682 kW/m2 was applied to the fiber webs using the high-pressure water jet injecting apparatus. This water jet treatment was repeated twice in substantially the same conditions and thereafter, the fiber webs were dried using a Yankee drying drum.
The thickness and the fiber density of the obtained fiber-interlacing nonwoven fabric are shown in the columns “Thickness” and “Density” of the column “Properties of fiber-interlacing nonwoven fabric” in Table 1.
The fiber-interlacing nonwoven fabrics of Examples 1 to 5 were cut into a size of 150 mm in the machine direction (MD) of the fiber webs and 25 mm in the cross direction (CD) which crosses the machine direction orthogonally to obtain the samples for the measurement of the properties and with respect to the thus obtained samples, the dry strength and the wet strength of the fiber-interlacing nonwoven fabric were measured. The measurement was performed through a tensile test in which the sample is held between the chucks of a tension tester so that the length of the sample in the longitudinal direction is 100 mm, and the distance between the chucks are expanded with a speed of 100 mm/min, thereby measuring the breaking strength (N/25 mm) of the sample as the maximum load which has been applied to the sample until the sample is broken.
The dry strength is the result of the tensile test performed with respect to the sample in a dry state and the wet strength is the result of the tensile test performed with respect to the sample which has been immersed in an ion-exchanged water for 10 sec. This tensile test was performed in an atmosphere having a room temperature of 25° C. and a relative humidity of 65%. The measured values are shown in the columns “Dry strength” and “Wet strength” of the column “Properties of fiber-interlacing nonwoven fabric” in Table 1.
Next, the water-decomposable sheets of Examples 1 to 4 were cut into a belt form having a size in the CD of 50 mm and by twining the resultant sheets as shown in
In measuring the wet strength of the twined string 4X, after the twined string 4X which is held between the chucks of a tension tester without loosening the twined string 4X was immersed in an ion-exchanged water for 10 sec, the resultant twined string 4X was subjected to a tensile test. The results of the measurement are shown in the columns “Dry strength” and “Wet strength” of the column “Properties after the twining” in Table 1.
The measurement of the water-decomposability was performed according to the measuring method explained in the section of the embodiments of the present invention. With respect to the samples prepared by cutting the fiber-interlacing nonwoven fabrics of Examples 1 to 5 into a size of 100 mm×100 mm, the time needed for the water-decomposition was measured. Also, with respect to the samples prepared by cutting the strings of Examples 1 to 4 into a length of 100 mm, the time needed for the water-decomposition was measured. The results of the measurement are shown in the column “Water-decomposability” in Table 1.
Among the Examples shown in Table 1, particularly in Examples 2 to 4, the fiber-interlacing nonwoven fabrics had a high dry strength (7.0 N/25 mm or more) and a high wet strength (1.0 N/25 mm or more). In Examples 2 to 4, the twined string could be easily formed by twisting, and during twining, the strings were not cut or broken. Further, in Examples 2 to 4, a high wet strength of the twined string of 8 N or more could be obtained. With respect to the time needed for the water-decomposition of the fiber-interlacing nonwoven fabric, the best value in Examples 1 to 4 and the value measured in Example 5 were 94 sec and 118 sec respectively and all values measured in Examples 1 to 5 were 300 sec or less. Among the twined strings which were formed in Examples 1 to 4, the highest value of the time needed for the water-decomposition of the twined string was 123 sec.
All of the fiber-interlacing nonwoven fabrics and the twined strings 4X which were produced in Examples 1 to 5 can be used for producing the cleaning product; however, for producing the fiber-interlacing nonwoven fabric having a dry strength of 7.0 N/25 mm or more, the fiber-interlacing nonwoven fabric is produced preferably comprising 10% by mass or more of pulp fibers. Further, for producing the fiber-interlacing nonwoven fabric having a wet strength of 1.0 N/25 mm or more and for producing the twined string 4X having a wet strength of 8.0 N/25 mm or more, the fiber-interlacing nonwoven fabric is produced preferably comprising 10% by mass or more of rayon fibers.
In Examples A to F shown in Table 2, the fiber-interlacing nonwoven fabrics were produced by a method comprising: papermaking fiber webs comprising 50% by mass of NBKP fibers and 50% by mass of viscose rayon fibers (having a titer of 1.1 dtex and a fiber length of 7 mm); and subjecting the resultant fiber webs to a water jet treatment under the same conditions as those used in Examples 1 to 5. The fiber weights per square-meter of the fiber-interlacing nonwoven fabrics produced in Examples A to F were set to respectively 15.0 g/m2, 20.0 g/m2, 50.0 g/m2, 100.0 g/m2, 120.0 g/m2 and 50.0 g/m2. The thickness and the density of the fiber-interlacing nonwoven fabrics are shown in the columns “Thickness” and “Density” of the column “Properties of fiber-interlacing nonwoven fabric” in Table 2. The dry strength, the wet strength and the time needed for the water-decomposition of the fiber-interlacing nonwoven fabric were measured in substantially the same manner as in Examples 1 to 5. The results of the measurement are shown in the columns “Dry strength”, “Wet strength” and “Water-decomposability” of the column “Properties of fiber-interlacing nonwoven fabric” in Table 2.
Further, using the water-decomposable sheets produced in Examples A to F, the same twinned strings as that shown in
From the results shown in Table 2, for maintaining a high dry strength of the water-decomposable sheet and a high wet strength of the twined string, the water-decomposable sheet has a fiber weight per square-meter of preferably 30 g/m2 or more. Further, so that the time needed for the water-decomposition of the fiber-interlacing nonwoven fabric is 400 sec or less and so that the time needed for the water-decomposition of the twined string is 700 sec or less, the water-decomposable sheet has a fiber weight per square-meter of preferably 120 g/m2 or less. The times of the twining per 25 cm of the sheet for enhancing the wet strength of the twined string is at least 4 times or more, preferably 10 times or more. The upper limit of the times of the twining is particularly not limited so long as the sheet is not broken; however, the preferable upper limit is around 30 times.
Since in the water-decomposable cleaning product according to the present invention, the cleaning part comprises a water-decomposable fiber-interlacing nonwoven fabric, when the cleaning is performed by the cleaning product which is wetted, the cleaning part neither is broken nor looses the form thereof, so that the dirt can be effectively removed by the cleaning product. Moreover, when the cleaning product is discarded into water after the use thereof, the interlacing of the fibers is loosened, so that the cleaning product becomes able to be easily water-decomposed.
By the production method of the water-decomposable cleaning product according to the present invention, the cleaning part having a high density and a high wet strength can be produced.
Although the present invention has been described above by reference to certain embodiments, the present invention is not limited to the embodiments described above. Modifications and variations of the embodiments described above will occur to those skilled in the art, in light of the above teachings.
The scope of the preset invention is defined with reference to the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2005-141414 | May 2005 | JP | national |
| Number | Name | Date | Kind |
|---|---|---|---|
| 2755497 | Greacen, Jr. | Jul 1956 | A |
| 2816313 | Beck et al. | Dec 1957 | A |
| 4995133 | Newell | Feb 1991 | A |
| 5789328 | Kurihara et al. | Aug 1998 | A |
| 6544912 | Tanio et al. | Apr 2003 | B1 |
| 20010023160 | Yamada et al. | Sep 2001 | A1 |
| 20010052162 | Young | Dec 2001 | A1 |
| 20020054784 | Wolf | May 2002 | A1 |
| Number | Date | Country |
|---|---|---|
| 62-186833 | Aug 1987 | JP |
| 11-93055 | Apr 1999 | JP |
| 2004-16637 | Jan 2004 | JP |
| 3103299 | Aug 2004 | JP |
| 3105217 | Oct 2004 | JP |
| 2005-7094 | Jan 2005 | JP |
| Number | Date | Country | |
|---|---|---|---|
| 20060258251 A1 | Nov 2006 | US |
