JP2019178446A - Water-disintegrable sheet and water-disintegrable sheet laminate body - Google Patents

Abstract

To provide a water-disintegrable sheet and a laminate body thereof, capable of reducing unevenness of its height on laminating under being folded without crushing forcibly.SOLUTION: The invention discloses a toilet cleaner 100 comprising a plurality of base paper sheets P having been laminated together and impregnated with a chemical solution, wherein the base paper sheet P includes an outer layer sheets P1 and P1 arranged on the front and the rear face of the toilet cleaner 100 and an inner layer sheet P2 arranged between the outer layer sheets P1 and P1, the basis weight of the inner layer sheet P2 being higher than that of outer layer sheets P1 and P1.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a water-decomposable sheet and a water-decomposable sheet laminate.

  Conventionally, woven cloth cloths that are used repeatedly have been used for cleaning toilets. Instead, disposable wet sheets made of paper have been used in recent years. This type of wet sheet is preferably provided in a state of being impregnated with a cleaning agent, and can be processed by flowing it into a toilet after use.

  Such a wet sheet is formed by laminating a plurality of base paper sheets, and is folded so that the wet sheet can be stored in a storage container or the like (see, for example, Patent Document 1).

2017-13484 publication

When the wet sheet is folded in this way, the end portion where many folds are formed becomes thicker, and thus the thickness becomes non-uniform. Such wet sheets are stacked in a folded state to form a stacked body, which is stored and sold in a storage container or the like. In this case, the folded wet sheet If the thickness of each sheet is non-uniform, in the laminated body in which these are stacked, the difference in thickness is accumulated, and the height varies greatly depending on the location.
Also, it is conceivable to make the thickness of the folded wet sheet uniform by crushing with a roller, but in this case, embossing is formed on the wet sheet, which becomes too difficult to use because the crease is too strong When it is done, the bad effect that this collapses occurs.

  The subject of this invention is providing the water-decomposable sheet and its laminated body which can reduce the nonuniformity of the height which arises when it laminates | stacks in the folded state, without crushing forcibly.

In order to solve the above-mentioned problem, the invention described in claim 1
A water-degradable sheet in which a plurality of base paper sheets are laminated and impregnated with a chemical solution,
The base paper sheet includes an outer layer sheet disposed on the front and back surfaces of the water-decomposable sheet, and an inner layer sheet disposed between the outer layer sheets,
The basis weight of the inner layer sheet is higher than the basis weight of the outer layer sheet.
According to the present invention, it is possible to provide a water-decomposable sheet that can reduce unevenness in height that occurs when the sheets are stacked in a folded state without being crushed by force.

The invention according to claim 2 is the water-decomposable sheet according to claim 1,
The basis weight of the inner layer sheet is higher by 0.5 g / m ² or more and 20 g / m ² or less than the basis weight of the outer layer sheet.
According to the present invention, it is possible to further reduce the unevenness in height that occurs when stacked in a folded state.

The invention according to claim 3 is the water-decomposable sheet according to claim 1 or 2,
The outer layer sheet includes polyvinyl alcohol fibers.
According to the present invention, it is possible to further reduce the unevenness in height that occurs when stacked in a folded state.

The invention according to claim 4 is the water-decomposable sheet according to claim 3,
The outer layer sheet contains 2.0% by weight or more and 4.0% by weight or less of polyvinyl alcohol fiber.
According to the present invention, it is possible to further reduce the unevenness in height that occurs when stacked in a folded state.

The invention according to claim 5 is the water-decomposable sheet according to any one of claims 1 to 4,
The outer layer sheet is creped.
According to the present invention, it is possible to further reduce the unevenness in height that occurs when stacked in a folded state.

The invention according to claim 6 is the water-decomposable sheet according to any one of claims 1 to 4,
The outer layer sheet and the inner layer sheet are creped, and the crepe rate of the outer layer sheet is 0.5% to 17% higher than the crepe rate of the inner layer sheet.
According to the present invention, it is possible to further reduce the unevenness in height that occurs when stacked in a folded state.

The invention according to claim 7 is the water-decomposable sheet according to any one of claims 1 to 6,
Embossing is formed on the entire surface of the base paper sheet.
According to the present invention, it is possible to further reduce the unevenness in height that occurs when stacked in a folded state.

The invention according to claim 8 provides:
The water-decomposable sheet laminated body according to any one of claims 1 to 7, which is folded a predetermined number of times, is a water-decomposable sheet laminate in which a plurality of sheets are laminated so that the direction in which folds are formed is common.
ADVANTAGE OF THE INVENTION According to this invention, the water-decomposable sheet laminated body which reduced the nonuniformity of height can be provided.

The invention according to claim 9 is the water-decomposable sheet laminate according to claim 8,
The water-decomposable sheet is folded only once in the MD direction and the CD direction.
ADVANTAGE OF THE INVENTION According to this invention, the water-decomposable sheet laminated body which reduced the nonuniformity of height can be provided.

  According to the present invention, it is possible to provide a water-decomposable sheet and a laminate thereof that can reduce unevenness in height that occurs when laminated in a folded state without being forced to crush.

It is a top view which shows an example of the toilet cleaner which concerns on embodiment. It is an enlarged view of the II-II part of FIG. It is sectional drawing in the III-III part of FIG. It is a figure which shows an example of how to fold the toilet cleaner which concerns on embodiment, (a) shows the toilet cleaner before folding, (b) shows the toilet cleaner of the state folded once, (c) folds twice Shows the toilet cleaner in the state. It is a flowchart which shows the manufacturing method of the toilet cleaner which concerns on embodiment. It is a schematic diagram which shows an example of the manufacturing equipment (solution provision equipment) of the toilet cleaner which concerns on embodiment. It is a schematic diagram which shows an example of the manufacturing equipment (processing equipment) of the toilet cleaner which concerns on embodiment. It is the schematic which shows an example of a papermaking apparatus. It is a side view of the toilet cleaner laminated body which concerns on embodiment. In addition, illustration of the unevenness | corrugation by the embossing formed in each toilet cleaner is abbreviate | omitted.

  Hereinafter, a water-decomposable sheet and a water-decomposable sheet laminate that are embodiments of the present invention will be described in detail with reference to the drawings. However, the scope of the invention is not limited to the illustrated examples.

  In the following, the toilet cleaner 100 will be described as an example, but the water-decomposable sheet of the present invention includes wet tissue impregnated with a chemical solution for wiping purposes other than the toilet cleaner. Further, the paper conveyance direction at the time of manufacturing the toilet cleaner 100 will be described as the Y direction (longitudinal direction, MD direction), and the direction orthogonal to the conveyance direction will be described as the X direction (lateral direction, CD direction).

[Composition of toilet cleaner 100]
First, the configuration of the toilet cleaner 100 will be described.
As shown in FIG. 3, the toilet cleaner 100 includes three base paper sheets P, that is, outer layer sheets P1 and P1 that form the front and back surfaces of the toilet cleaner 100, and an inner layer sheet P2 that forms an inner layer of the toilet cleaner 100, Are ply-processed (laminated) and impregnated with a predetermined chemical solution.
Further, it is possible to stack further base paper sheets P to form a sheet of 4 plies or more.
Further, a large number of embossed EMs 11 are formed on the entire surface of the toilet cleaner 100 by embossing as shown in FIGS.

  Further, the toilet cleaner 100 is stored in a folded plastic case, packaging film, or the like in a folded state, and is expanded and used as needed during use. In addition, how to fold the toilet cleaner 100 will be described later.

{Base paper sheet}
The base paper sheet P that forms the toilet cleaner 100 includes outer layer sheets P1 and P1 that form the front and back surfaces of the toilet cleaner 100, and an inner layer sheet P2 that forms the inner layer of the toilet cleaner 100, as shown in FIG. Both are composed of a water-degradable fiber assembly so that after the toilet is cleaned, it can be discarded as it is in the toilet puddle.
In addition, in order to improve the surface strength, the toilet cleaner 100 is coated with a solution containing a water-soluble binder such as carboxymethylcellulose (CMC) from the front and back as a binder solution for enhancing paper strength. It is preferable that the content of CMC increases from the surface toward the front surface and back surface. In this case, the toilet cleaner 100 is less likely to be broken even if the edge of the toilet bowl is rubbed strongly, compared to a conventional product that is uniformly impregnated with a water-soluble binder.

  The outer layer sheets P1 and P1 and the inner layer sheet P2 are sheets having different properties. Specifically, it is as follows.

(Outer layer sheet)
The outer layer sheets P1 and P1 are sheets that form the front and back surfaces of the toilet cleaner 100 as shown in FIG.

As the fiber assembly forming the outer layer sheets P1 and P1, it is preferable to use a mixture of polyvinyl alcohol (PVA) fibers. In addition to PVA fibers, wood pulp (hardwood bleached kraft pulp (LBKP) and / or softwood bleached kraft pulp (NBKP)) is included.
The mixing ratio of the PVA fiber is preferably 2.0% by weight or more and 4.0% by weight or less, and more preferably 2.5% by weight or more and 3.0% by weight or less.
Further, other than PVA fibers, hardwood bleached kraft pulp (LBKP) is preferably 20 wt% or more and 70 wt% or less, and softwood bleached kraft pulp (NBKP) is preferably 30 wt% or more and 80 wt% or less. More preferably, the pulp (LBKP) is 20% by weight or more and 40% by weight or less, and the softwood bleached kraft pulp (NBKP) is 60% by weight or more and 80% by weight or less.

The basis weight of each of the outer layer sheets P1 and P1 is preferably 25 g / m ² to 50 g / m ² , and more preferably 30 g / m ² to 45 g / m ² .

  Further, the outer layer sheets P1 and P1 may be creped. In that case, the crepe rate is preferably 5% to 20%, and more preferably 10% to 15%.

  When both the outer layer sheets P1, P1 and the inner layer sheet P2 are creped, the crepe rate of the outer layer sheets P1, P1 is higher than the crepe rate of the inner layer sheet P2 within the above range. It is preferable. Specifically, it is preferably 0.5% to 17% higher than the crepe rate of the inner layer sheet P2, and more preferably 3% to 15% higher.

(Inner layer sheet)
As shown in FIG. 3, the inner layer sheet P2 is a sheet that forms an inner layer of the toilet cleaner 100 disposed between the outer layer sheets P1 and P1.

As a fiber assembly which forms the inner layer sheet P2, what does not contain PVA fiber and contains wood pulp (broadwood bleached kraft pulp (LBKP) and / or softwood bleached kraft pulp (NBKP)) is used.
The mixing ratio is preferably 20% to 70% by weight for hardwood bleached kraft pulp (LBKP) and 30% to 80% by weight for softwood bleached kraft pulp (LBKP). ) Is 20% by weight or more and 40% by weight or less, and softwood bleached kraft pulp (NBKP) is more preferably 60% by weight or more and 80% by weight or less.

The basis weight of the inner layer sheet P2 is preferably 28 g / m ² to 53 g / m ² , and more preferably 33 g / m ² to 48 g / m ² . Incidentally, in the above range, there is a need for a higher value than the basis weight of the outer layer sheet P1, P1, specifically, the outer layer sheet P1, P1 be 20 g / ^{m 2} high from 0.5 g / ^{m 2} than the basis weight of preferably, it is more preferably from 1g / ^{m 2} 18g / ^{m 2} high.

  Further, the inner layer sheet P2 may be creped. In that case, the crepe rate is preferably 2% to 17%, more preferably 7% to 12%.

  In addition, when the outer layer sheets P1 and P1 are creped, it is preferable that the inner layer sheet P2 is not creped, and both the outer layer sheets P1 and P1 and the inner layer sheet P2 are creped. When applied, the crepe rate of the inner layer sheet P2 is preferably lower than the crepe rate of the outer layer sheets P1 and P1 within the above range. Specifically, it is preferably 0.5% to 17% lower than the crepe rate of the outer layer sheets P1, P1, and more preferably 3% to 15% lower.

{Chemical solution}
The toilet cleaner 100 is impregnated with a predetermined chemical solution containing an auxiliary agent such as a fragrance, an antiseptic, a disinfectant, a paper strength enhancer, and an organic solvent in addition to an aqueous cleaning agent.

  As the chemical solution, an appropriate one can be used. For example, as the aqueous cleaning agent, a surfactant or a lower or higher (aliphatic) alcohol can be used. As a fragrance | flavor, 1 type or several types can be suitably selected and used out of oil-based fragrance | flavors, such as orange oil other than an aqueous | water-based fragrance | flavor. As the preservative, for example, parabens such as methyl paraben, ethyl paraben, propyl paraben and the like can be used. As a disinfectant, for example, benzalkonium chloride, chlorhexidine gluconate, popidone iodine, ethanol, benzilium cetyl oxide, triclosan, chlorxylenol, isopropylmethylphenol and the like can be used. As the paper strength enhancer (crosslinking agent), boric acid, various metal ions, and the like can be used. As the organic solvent, polyhydric alcohols such as glycol (divalent), glycerin (trivalent), and sorbitol (tetravalent) can be used.

  In addition, the above-mentioned auxiliary agent for the component of the chemical solution can be appropriately selected, and a component that performs other functions may be included in the chemical solution as necessary.

  The chemical solution impregnation rate is preferably 120% to 200%, and more preferably 150% to 180%. If it is this ratio, it will become easy to clean while maintaining moderate water | moisture content and releasing.

{Emboss}
A large number of embossed EMs 11 are formed on the entire surface of the toilet cleaner 100 in a state in which the outer layer sheets P1 and P1 and the inner layer sheet P2 are plyed.
As shown in FIGS. 1 and 2, the emboss EM 11 is formed in an elliptical shape that is short in the Y direction.
Further, the emboss EM 11 includes a convex emboss EM 21 that is convex toward the front side of the drawing in FIG. 1 and a concave emboss EM 22 that is concave toward the front side of the drawing in FIG.

Further, as shown in FIG. 2, the embosses processed on the entire surface of the toilet cleaner 100 are alternately arranged so that the convex emboss EM21 and the concave emboss EM22 are alternately arranged in both the X direction and the Y direction. An embossing pattern having an intermediate portion MD21 that is an unembossed portion is formed between the concave embossed EM22.
Further, the convex emboss EM21 and the concave emboss EM22 are formed to have the same shape when reversed at the intermediate part MD21.

  Thus, the convex embossing EM21 and the concave embossing EM22 are alternately formed both in the X direction and in the Y direction, so that it is possible to wipe off dirt more than the embossed pattern in which the convex portions and the concave portions are arranged in a row. Can be improved.

  The shape and arrangement of the convex emboss EM21 and the concave emboss EM22 are not limited to the above. For example, as the shape of the emboss, a circle, an ellipse, a polygon or the like is used, and the shapes may be combined.

Further, the emboss EM 11 may be formed on the entire surface of the toilet cleaner 100 as shown in FIG. 1, but may be formed around, for example, a fold where the toilet cleaner 100 is folded.
The embossing EM11 has the effect of making the sheet bulky, and this is formed so as to avoid the vicinity of the crease, so that when the toilet cleaner 100 is folded, the side where many creases are formed is further suppressed from becoming thick. It becomes easy to do.
Further, the height of the emboss EM 11 may be lowered only in the vicinity of the crease while the emboss EM 11 is formed on the entire surface.

{How to fold}
The toilet cleaner 100 is sized so that it can be stored in a storage plastic case, packaging film, or the like by being folded a plurality of times at a fold parallel to the X direction or the Y direction. Specifically, as shown in FIG. 4, it is preferable that each of the fold lines parallel to the X direction and the fold lines parallel to the Y direction is folded once and folded by a quarter.

Normally, a toilet cleaner is formed in a rectangular shape that is long in the MD direction, and is folded once at the center position in the CD direction, and further folded twice in the MD direction, so that it is folded in an eighth.
On the other hand, when the size of the toilet cleaner is halved in the MD direction from the beginning, and the number of times of folding is limited to one time in each direction, the number of folds is reduced, and when cleaning is performed with widening. It becomes difficult to get caught and cleaning becomes easier.

Moreover, it is preferable that the crease | fold when the toilet cleaner 100 is folded is formed in the flat part in which the convex embossing EM21 and the concave embossing EM22 are not formed.
In this case, it is easy to fold the sheet, and it is possible to prevent the emboss from being broken by the folding process.

[Perforation]
The toilet cleaner 100 may be provided with perforations for dividing it.
For example, a perforated toilet cleaner 100 that is long in the CD direction shown in FIG. 1 is provided with a perforation parallel to the MD direction at the center in the CD direction so that it can be divided into two minutes in the CD direction.
This makes it possible to evenly divide a toilet cleaner, and it is easy for the user to divide it into multiple times.

Such a perforation can be provided at a position overlapping the fold line at the time of folding or at a different position.
When the perforation is provided at a position overlapping the crease, the perforation strength can be further reduced, and when the perforation is provided at a position different from the fold, a reduction in the perforation strength can be suppressed. Therefore, when the perforation is provided at a position overlapping with the fold, the user can easily divide the sheet by the perforation. On the other hand, when the perforation is provided at a position different from the fold line, it is possible to reduce the possibility that the user unintentionally divides the sheet due to the perforation.
Moreover, it is preferable that the perforation is formed in the flat part in which the convex embossing EM21 and the concave embossing EM22 are not formed so that the shape of embossing may not be destroyed.

{Laminate}
Next, a toilet cleaner laminate 200 in which a plurality of toilet cleaners 100 according to the embodiment are laminated will be described with reference to FIG.

  As shown in FIG. 9, the toilet cleaner laminated body 200 is obtained by laminating a plurality of toilet cleaners 100 in a folded state. If the direction in which the folds are formed varies, the direction of the folds will be different each time the toilet cleaner 100 is taken out, resulting in confusion for the user. Thus, they are laminated.

Specifically, for example, each toilet cleaner 100 is folded once each in a fold line parallel to the X direction and a fold line parallel to the Y direction as shown in FIG. 4, and this is folded as shown in FIG. The layers are laminated so that the directions of the two coincide.
In FIG. 9, the toilet cleaner 100 is folded so that the fold when the toilet cleaner 100 is folded a second time is located on the right side of the drawing, and the fold when the toilet cleaner 100 is folded once is located on the back side of the drawing. However, the present invention is not limited to this. For example, more or fewer toilet cleaners 100 may be stacked.

[Effect of toilet cleaner 100]
In the case of a two-ply sheet using the same base paper sheet, when impregnated with a chemical solution, the chemical solution is dispersed throughout the sheet even when folded.
On the other hand, according to the toilet cleaner 100 according to the embodiment, the outer layer sheet P1, the inner layer sheet P2, and the outer layer sheet P1 are three-ply sheets laminated in this order, and the outer layer sheets P1 and P1, the inner layer sheet P2 and By using different sheets, a large amount of the chemical solution is held at the fold portion.

Specifically, since the PVA fiber is contained only in the outer layer sheet, the outer layer sheets P1 and P1 are difficult to stretch because the PVA fiber is crosslinked when being folded and impregnated with the chemical solution. On the other hand, the inner layer sheet P2 that does not contain PVA fibers is more easily stretched than the outer layer sheets P1 and P1 because the fibers are not crosslinked.
As a result, only the inner layer sheet P2 tends to stretch greatly, and thus the sheet is distorted. In particular, a space is easily generated in the fold portion of the sheet, so that a large amount of chemical solution is held in the fold portion.
Such an effect can be enhanced when the proportion of PVA fibers in the fiber assembly forming the outer layer sheets P1 and P1 is within the above range.

Moreover, when the weight of the inner layer sheet P2 is higher than that of the outer layer sheets P1 and P1, when the inner layer sheet P2 is folded and impregnated with the chemical solution, the inner layer sheet P2 having a higher weight per unit area is compared with the outer layer sheets P1 and P1. Thus, a lot of chemical solution is held. As a result, a large amount of the chemical solution is supplied from the inner layer sheet P2 to the space generated in the fold portion of the toilet cleaner 100, so that a large amount of the chemical solution is held in the fold portion.
Such an effect can be enhanced when the basis weight of the outer layer sheets P1 and P1 and the basis weight of the inner layer sheet P2 are within the above ranges.

  Further, when the outer layer sheets P1, P1 are creped and the inner layer sheet P2 is not creped, or both the outer layer sheets P1, P1 and the inner layer sheet P2 are creped. When the crepe rate of the inner layer sheet P2 is lower than that of the outer layer sheets P1 and P1, when folded and impregnated with the chemical solution, the outer layer sheets P1 and P1 are compared with the inner layer sheet P2 in the sheet. Prone to wrinkles. As a result, a space is likely to be generated particularly in the fold portion of the sheet, so that a large amount of chemical solution is held in the fold portion.

  Moreover, the positional relationship of these sheets is fixed by embossing the outer layer sheets P1, P1 and the inner layer sheet P2 in a state where they are laminated. As a result, the positional relationship of the sheet does not move and distortion is not eliminated, and the space generated in the fold portion of the sheet is easily maintained, so that a large amount of chemical liquid is easily held in the fold portion.

Furthermore, when a plurality of folded toilet cleaners are laminated so that the direction of the folds are aligned, and a toilet cleaner laminate is formed, the folded sheet inevitably becomes thicker on the side where there are many folds. The side of the toilet cleaner where many folds are formed becomes higher. However, according to the toilet cleaner 100 according to the present embodiment, the amount of impregnation of the chemical solution in the crease portion is increased, and the side on which many creases are formed becomes heavier. On the side where a large number of folds are formed in 100, this is more strongly compressed by its own weight, and the height of the toilet cleaner laminate 200 can be made uniform.
In addition, when forming the toilet cleaner laminate, it is possible to make the height of the toilet cleaner laminate even by laminating the toilet cleaner so that the side where many creases are formed is divided. However, in this case, every time the user takes out the toilet cleaner, the direction of the fold is different, which causes confusion for the user.
According to the toilet cleaner 100 according to the present embodiment, the crease direction can be unified, and the height of the toilet cleaner laminate 200 can be made uniform without causing such harmful effects.

In addition, the toilet cleaner 100 is formed in a size that can be wrapped only by folding once in the MD direction and the CD direction, and the number of foldings is limited to one in each direction. When performing cleaning by spreading it out, it becomes difficult to get caught, and cleaning becomes easier.
However, in this case, in the folded state, two sides where the folds are formed are formed, while two sides where no folds are formed are formed. Compared with the case where it is made, when it is set as a toilet cleaner laminated body, the difference in height tends to arise.
However, in this embodiment, even in such a case, the height of the toilet cleaner laminate 200 can be made uniform, so that the present invention is particularly effective when such a four-fold sheet is used. It can be said that there is.

[Manufacturing method of toilet cleaner 100]
Next, an example of a method for manufacturing the toilet cleaner 100 will be described.
FIG. 5 is a flowchart showing a method for manufacturing the toilet cleaner 100. FIG. 6 is a schematic diagram of a solution application facility for applying a binder solution to the base paper sheet of the toilet cleaner 100. FIG. 7 is a schematic diagram of processing equipment for processing a base paper sheet to which a binder solution has been applied by the solution application equipment shown in FIG.

  In the manufacturing method of the toilet cleaner 100, as shown in FIG. 5, first, a paper making process (S1) for making a paper as a base paper with a paper machine (not shown) is performed.

  Next, as shown in FIG. 5 and FIG. 6, the ply-processed continuous dry base papers 1 </ b> A and 1 </ b> A fed out from the two primary raw rolls 1 and 1, each of which is made of the base paper that has been made, are rolled in a solution application facility. Further, ply processing is performed by stacking another continuous dry base paper 1A to form a continuous ply sheet 1B (S2), and application of a solution to provide a continuous sheet 1C by applying a binder solution to the continuous ply sheet 1B. A step (S3), a drying step (S4) for drying the continuous sheet 1C, and a slit / winding step (S5) for slitting and winding the dried continuous water-degradable sheet 1D are performed.

  Next, as shown in FIGS. 5 and 7, in the processing facility, the continuous water-decomposable sheet 1 </ b> D fed from the secondary raw roll 11 wound in the slit / winding step (S <b> 5) is embossed. An embossing process (S6) and a finishing process (S7) for finishing the embossed sheet 1E that has been embossed are performed. Details of each process will be described later.

[Paper making process]
First, the paper making process (S1) according to the present embodiment will be described. In the papermaking step (S1) of the present invention, for example, a raw paper sheet P is formed by making a papermaking raw material by a known wet papermaking technique. That is, after making the papermaking raw material into a wet paper state, it is dried by a dryer or the like to form a base paper sheet P such as thin paper or crepe paper.
As the raw paper sheet P raw material fibers, those blended in the ratio shown in the paragraph [0023] per outer layer sheet P1 are used, and those blended in the ratio shown in the paragraph [0027] per inner layer sheet P2 are used. It is done.
The base paper sheet of the present invention contains an anionic acrylamide polymer (hereinafter referred to as “anionic PAM”) as a flocculant. An anionic PAM is a polymer obtained by copolymerizing an acrylamide monomer and an anionic monomer.
Examples of the acrylamide monomer include acrylamide alone or a mixture of acrylamide and the following nonionic monomer copolymerizable with acrylamide. Nonionic monomers copolymerizable with acrylamide include methacrylamide, N, N-dimethylacrylamide, N, N-diethylacrylamide, N-isopropylacrylamide, N-isopropylacrylamide, N-hydroxyethylacrylamide, diacetone. Examples include acrylamide, acryloylmorpholine, N-acryloylpyrrolidine, N-acryloylpiperidine, N-vinylrolidone, N-vinylformamide, and N-vinylacetamide. These may be used alone or in combination of two or more.
Examples of the anionic monomer include acrylic acid, methacrylic acid, acrylamide-2-methylpropanesulfonic acid, itaconic acid, maleic acid, fumaric acid, and neutralized salts thereof.
It should be noted that monomers such as styrene, acrylonitrile, (meth) acrylic acid ester and the like may be added as long as the water solubility of the anionic PAM is not impaired.
The addition amount of the anionic PAM is preferably about 10 to 1000 ppm. By making paper using such an anionic flocculant having the same charge as pulp, the aggregation of the base paper sheet can be reduced, and the water disintegrability can be improved by capillary action.
In addition to the pulp and the flocculant described above, papermaking chemicals such as a wet paper strength agent, an adhesive, and a release agent may be appropriately used for the base paper sheet.
Moreover, in embodiment of this invention, although a binder solution is provided in the solution provision process of the solution provision equipment mentioned later, you may make it provide a binder solution in the step of a papermaking process.
When the binder solution is applied even in the papermaking process, the strength of the entire water-decomposable sheet can be increased, and by further applying the binder solution in the solution-applying process in the subsequent process, the surface strength of the water-decomposable sheet is further increased. Can be raised.

  As a method for applying the binder solution in the papermaking process, for example, a water-soluble binder and a fixing agent to the pulp fiber of the water-soluble binder are added to a dispersion liquid containing pulp as a papermaking raw material, and this is used as a raw material. A paper making method is known (Japanese Patent Laid-Open No. 3-193996). That is, it is a method of internally adding a water-soluble binder. Alternatively, a sheet made from a pulp-containing dispersion may be wet-papered, press dehydrated or semi-dried, and then a water-soluble binder may be spray-dried or coated and dried to produce a fiber sheet containing a predetermined amount of the water-soluble binder. Is possible. That is, it is a method of externally adding a water-soluble binder. In this case, a fiber sheet having a lower density and better water disintegration can be obtained by using a pre-drying system such as a hot-air passing dryer than performing press dewatering. Furthermore, instead of the above-mentioned wet papermaking method, it is also possible to produce a fiber sheet by drying fiber pulp dry without using water, forming a web, spraying a water-soluble binder, and then drying. . This is the so-called airlaid manufacturing method.

  FIG. 8 shows a schematic view of an example of a production apparatus preferably used for producing a fiber sheet when a water-soluble binder is used as the binder. The manufacturing apparatus (wet papermaking machine) shown in FIG. 8 includes a former 14, a wire part, a first dry part 17, a spray part, and a second dry part 24.

  The former 14 adjusts the furnish supplied from a preparation device (not shown) to a predetermined concentration and supplies it to the wire part. A preparation device (not shown) includes a device that beats and beats raw materials such as pulp fibers, and an addition device that adds additives such as sizing agents, pigments, paper strength enhancers, bleaching agents, and flocculants to the beaten and beaten raw materials. And a stock made of a raw material having a predetermined concentration according to the characteristics of hydrolyzed paper is prepared as a finished stock. It is also possible to mix a binder with the pulp slurry. The wire part is a wet paper that forms the paper stock supplied from the former as a wet paper. The first dry part 17 dries the wet paper formed in the wire part. The spray part sprays the binder onto the paper dried by the first dry part 17. The 2nd dry part 24 dries the paper which has been sprayed with the binder and is wet.

  The furnish supplied from the former 14 is made in the wire part, and a wet paper is formed on the wire 15. Water is removed from the wet paper by suction by a suction box 16 installed in the wire part, and the wet paper has a predetermined moisture content. Next, the wet paper is introduced into the first dry part 17 and dried. The first dry part 17 is composed of a through air dryer (hereinafter referred to as TAD). The TAD includes a rotating drum 18 having a breathable peripheral surface, and a hood 19 that covers the rotating drum 18 almost airtightly. In TAD, air heated to a predetermined temperature is supplied into the hood 19. The heated air flows from the outside of the rotating drum 18 toward the inside. The wet paper web is conveyed in a state of being held on the peripheral surface of the rotary drum 18 rotating in the direction of the arrow in FIG. While being transported in the TAD, the heated paper penetrates the wet paper in the thickness direction, whereby the wet paper is dried to become paper.

  The paper obtained in the first dry part 17 is sprayed with an aqueous solution (binder solution) containing a binder in the spray part. The spray part is a position between the first and second dry parts 17 and 24. Both dry parts 17 and 24 are connected via a conveyor.

  The conveyor includes an upper conveyor belt 20 and a lower conveyor belt 21 that rotate in the directions indicated by the arrows. The conveyor 20 is configured to convey paper to the second dry part 24 while being dried by the TAD of the first dry part 17 and sandwiching the paper between the belts 20 and 21. A vacuum roll 22 is disposed at the folded end on the downstream side of the upper conveyor belt 20. The vacuum roll 22 adsorbs paper on the back surface of the upper conveyor belt 20 and conveys the upper conveyor belt 20 under the adsorbed state.

  As shown in FIG. 8, the spray part includes a spray nozzle 23. The spray nozzle 23 is disposed below the second dry part 24 and so as to face the vacuum roll 22. The spray nozzle 23 sprays a spray liquid containing a binder toward the vacuum roll 22 and adds (externally adds) the spray liquid to paper.

  After the binder is supplied in the spray part, the paper is conveyed to the second dry part 24. The second dry part 24 is composed of a Yankee dryer. The paper that has been sprayed with the spray liquid and is in a wet state is conveyed while being held on the peripheral surface of the rotary drum 25 of the Yankee dryer installed in the hood 26. The paper is dried while being held by the rotary drum 25 and conveyed.

  In addition, the position where the binder is supplied in the spray part may be a position between the first and second dry parts 17 and 24. For example, the position above the upper conveyor belt 20 (the first and second dry parts shown in FIG. 8). You may make it spray a binder from the arrow position between 17 and 24). Further, the binder may be sprayed from above (the arrow position on the right side of the second dry part 24 shown in FIG. 8) on the paper after being dried by the second dry part 24. In addition, the direction in which the binder is sprayed between the first and second dry parts 17 and 24 and after the second dry part 24 is not limited to the upper direction, and may be from the lower side or from the upper and lower sides.

  In the present embodiment, in the paper making process, adjustment is preferably performed so that the ratio of vertical and horizontal fiber orientations (vertical / horizontal) of the base paper sheet is 0.8 to 2.0, preferably 1.0. The fiber orientation can be adjusted, for example, by adjusting the angle at which the papermaking raw material is supplied to the wire part in a paper machine. The angle at which the papermaking raw material is supplied can be determined, for example, by adjusting the slice opening degree of the head box. Or it is good also as adjusting fiber orientation by giving a vibration in the direction orthogonal to the conveyance direction (running direction) of a paper machine.

[Continuous dry base paper]
The continuous dry base paper 1A becomes a ply-processed hydrolyzed paper through a ply processing step (S2), a solution application step (S3), a drying step (S4), and a slit / winding step (S5), which will be described later. The toilet cleaner 100 is processed through an embossing process (S6) and a finishing process (S7).

[Ply processing process]
Next, the ply processing step (S2) of this embodiment will be described. In the ply processing step (S2), as shown in FIG. 6, the continuous dry base papers 1A and 1A that are continuously fed from the primary raw rolls 1 and 1 are ply processed along the continuous direction, and the ply continuous sheet 1B is supplied to the overlapping unit 2. The overlapping portion 2 is composed of a pair of rolls, and plies each continuous dry base paper 1A, 1A. A ply continuous sheet 1B obtained by plying three continuous dry base papers 1A is formed by further plying one continuous dry base paper 1A on the two-ply sheet thus formed. In addition, when the continuous dry base papers 1A and 1A are overlapped, the continuous dry base papers 1A and 1A may be lightly fastened with pin embossing (contact embossing) so that they are not easily displaced.
Of the ply continuous sheet 1B thus formed, the uppermost continuous dry base paper 1A and the lowermost continuous dry base paper 1A are the outer layer sheets P1, and the continuous dry base paper 1A therebetween is the inner layer sheet P2. .

[Binder solution]
Next, the binder solution will be described. The binder solution contains carboxymethyl cellulose (CMC) as a water-soluble binder. The concentration of carboxymethyl cellulose in the binder solution is 1 to 30% by weight, preferably 1% by weight or more and less than 4% by weight.

  On the other hand, the degree of etherification of CMC is desirably 0.6 to 2.0, particularly 0.9 to 1.8, and more preferably 1.0 to 1.5. The expression of water disintegration and wet paper strength is very good.

  Moreover, CMC can use a water-swellable thing. This demonstrates the function of tying together the fibers constituting the sheet while remaining unswelled by crosslinking of specific metal ions in the chemical solution, and can exhibit strength as a wiping sheet that can withstand cleaning and wiping operations.

  Ingredients other than carboxymethylcellulose in the binder solution include polyvinyl alcohol, starch or derivatives thereof, hydroxypropylcellulose, sodium alginate, tolton gum, guar gum, xanthan gum, gum arabic, carrageenan, galactomannan, gelatin, casein, albumin, pull plan, poly Examples thereof include binder components such as ethylene oxide, viscose, polyvinyl ethyl ether, polyacrylic acid soda, polymethacrylic acid soda, polyacrylamide, hydroxylated derivatives of polyacrylic acid, and polyvinylpyrrolidone / vinylpyrrolidone vinyl acetate copolymer.

It is preferable to use a water-soluble binder having a carboxyl group from the viewpoint of good water decomposability and a point at which wet strength can be expressed by a crosslinking reaction.
The water-soluble binder having a carboxyl group is an anionic water-soluble binder that easily forms a carboxylate in water. Examples thereof include polysaccharide derivatives, synthetic polymers, and natural products. Examples of the polysaccharide derivative include a salt of carboxymethyl cellulose, carboxyethyl cellulose or a salt thereof, carboxymethylated denven or a salt thereof, and an alkali metal salt of carboxymethyl cellulose is particularly preferable.

  Examples of the synthetic polymer include a salt of an unsaturated carboxylic acid polymer or copolymer, a salt of a copolymer of an unsaturated carboxylic acid and a monomer copolymerizable with the unsaturated carboxylic acid, and the like. Examples of the unsaturated carboxylic acid include acrylic acid, methacrylic acid, itaconic acid, crotonic acid, maleic anhydride, maleic acid, and fumaric acid. Examples of monomers that can be copolymerized with these include esters of these unsaturated carboxylic acids, vinyl acetate, ethylene, acrylamide, and vinyl ether. Particularly preferred synthetic polymers are those using acrylic acid or methacrylic acid as the unsaturated carboxylic acid. Specifically, polyacrylic acid, polymethacrylic acid, acrylic acid-methacrylic acid copolymer salt, acrylic acid or methacrylic acid. Examples thereof include a salt of a copolymer of an acid and an alkyl acrylate or an alkyl methacrylate. Examples of natural products include sodium alginate, xanthan gum, gellan gum, tarragant gum, pectin and the like.

[Solution application process]
Next, the solution application step (S3) of this embodiment will be described. In the solution application step (S3), as shown in FIG. 6, the binder solution is sprayed on the outer surfaces of both the ply continuous sheets 1B by the two-fluid type or one-fluid type spray nozzles 3 and 3, and the continuous sheet 1C. Is generated.
The ply continuous sheet 1B immediately after the ply processing in the ply processing step is merely overlapped with the continuous dry base papers 1A, 1A, 1A. Therefore, the binder solution is sprayed from both sides of the ply continuous sheet 1B in the solution application step. When applied with the nozzles 3 and 3, it is substantially the same as the case where the binder solution is applied with the continuous dry base papers 1A, 1A and 1A being separated, the binder solution permeates in the thickness direction, and the sheets are conveyed while being conveyed. It adheres and penetrates further during pressure bonding in the slit / winding process.
In addition, as a spraying method of a binder solution, you may make it spray the above-mentioned binder solution on the one outer surface of the ply continuous sheet 1B. Further, of the continuous dry base papers 1A, 1A, 1A, the above binder solution is sprayed from a two-fluid type spray nozzle onto the upper surface and the lower surface of the ply continuous sheet 1B which is located at the uppermost portion. Then, the continuous dry base paper 1A, 1A, 1A may be plyed to generate a sheet equivalent to the above-described continuous sheet 1C.

The two-fluid spray nozzle 3 is a spray nozzle that mixes and sprays compressed air and liquid divided into two systems, compared to a one-fluid spray nozzle that sprays compressed liquid alone, The liquid can be sprayed finely and uniformly.
When a two-fluid spray nozzle is used in the present embodiment, a binder solution (viscosity 400 to 1200 MPa.s) is applied to each outer surface of the ply-processed ply continuous sheet 1B with a high pressure (injection pressure of 1.5 MPa or more). Since it is applied, it is easy to impregnate the binder solution in the thickness direction of the sheet.
On the other hand, when a one-fluid spray nozzle is used in the present embodiment, a binder solution (viscosity 400 to 1200 MPa.s) is applied to the outer surface of each ply-processed ply continuous sheet 1B at an injection pressure of 1.5 MPa or less. Thus, the binder solution is easily impregnated in the thickness direction of the sheet, and the binder solution is easily applied uniformly on the sheet surface.
In this way, by spraying the binder solution onto the outer surface of the ply continuous sheet 1B, the toilet cleaner 100 is centered in the thickness direction (when applied on both sides) or non-coated with the binder solution (when applied on one side). Since the content of the water-soluble binder increases as it goes from the surface to the application surface of the binder solution, the surface strength can be improved while ensuring water disintegration, and the toilet cleaner 100 is less likely to be damaged even when rubbed strongly. Can be manufactured.

[Drying process]
Next, the drying step (S4) of this embodiment will be described. In the drying step (S4), as shown in FIG. 6, in the drying equipment 4, the insoluble liquid in the binder solution of the continuous sheet 1C is evaporated to fix the active ingredient, particularly CMC, to the fibers. .
Here, since the amount of the binder solution that permeates decreases from the outer surface of the continuous sheet 1C toward the inside in the thickness direction, the fixing amount of CMC decreases toward the inside in the thickness direction. Therefore, when the chemical solution is impregnated in the finishing step (S7) to be described later, the cross-linking reaction is less likely to occur toward the inside in the thickness direction, and since there are many voids, the surface strength of the sheet is improved while being flexible. Can be suppressed. Moreover, it can be set as the state which enclosed the said chemical | medical solution inside the sheet | seat. Thereby, the wiping property of the obtained toilet cleaner 100 can be improved, and the toilet cleaner 100 can be made difficult to dry.
As the drying equipment 4, a hooded dryer equipment that blows hot air on the continuous sheet 1C to dry it can be used. In order to make the sheets more closely contact each other, a press roll or a turn roll may be installed, and the continuous sheet 1C may be passed through the press roll or the turn roll before the drying step (S4).

  Moreover, you may use the installation by infrared irradiation as said drying installation. In this case, a plurality of infrared irradiation units are arranged in parallel in the conveying direction of the continuous sheet 1C, and drying is performed by irradiating the continuous sheet 1C to be conveyed with infrared rays. Since moisture is generated by infrared rays and dried, uniform drying is possible as compared with a dryer using hot air, and wrinkles can be prevented from occurring in the subsequent slit / winding process.

[Slit and winding process]
Next, the slit / winding step (S5) of this embodiment will be described. In the slit / winding step (S5), in order to use the ply-processed continuous water-decomposable sheet 1D with an off-line processing machine, it is dried in the drying step (S4) and the CMC is fixed. The illustrated continuous water-decomposable sheet 1D is slit to a predetermined width by the slitter 5 while adjusting the tension, and wound by the winder facility 6. The winding speed is appropriately determined in consideration of the ply processing step (S2), the solution application step (S3), and the drying step (S4). Note that if it is too early, the sheet will break, and if it is too late, wrinkles will occur.
In the slit / winding step (S5), the continuous water-decomposable sheet 1D subjected to the ply process is pressure-bonded, whereby the continuous water-decomposable sheet 1D is more integrated and becomes a sheet corresponding to one sheet.

[Embossing process]
Next, the embossing process (S6) of this embodiment will be described. In the embossing step (S6), as shown in FIG. 7, the embossing roll 12 has an embossing process that forms a predetermined shape on the entire surface of the continuous water-decomposable sheet 1D fed from the secondary raw roll 11 by the embossing roll 12. Applied. This embossing is performed for the purpose of improving the strength, bulkiness, wiping property and the like of the sheet, as well as the design.

[Finishing process]
Next, the finishing process (S7) of this embodiment will be described. In the finishing process (S7), as shown in FIG. 7, in the finishing equipment 13, the embossed sheet 1E is cut, the cut sheets are folded, and the chemicals are applied to the folded sheets. Impregnation is performed in a series of flows. Here, when CMC is used as the water-soluble binder, the cross-linking agent contained in the chemical solution is preferably a polyvalent metal ion. In particular, the use of one or more polyvalent metal ions selected from the group consisting of alkaline earth metals, manganese, zinc, cobalt, and nickel allows the fibers to be sufficiently bonded to withstand use. It is preferable from the standpoint that strength is developed and water disintegration is sufficient. Of these metal ions, it is particularly preferable to use ions of calcium, strontium, barium, zinc, cobalt, and nickel.
The toilet cleaner 100 is manufactured through the above steps.

  In the finishing process (S7), the toilet cleaner 100 may be perforated. Specifically, a perforation is made at a predetermined position of the toilet cleaner by a cutter, a blade or the like in parallel with the MD direction and / or the CD direction. This makes it possible to evenly divide a toilet cleaner, and it is easy for the user to divide it into multiple times.

  Further, a plurality of toilet cleaners 100 that have undergone a finishing process are stacked to form a toilet cleaner laminate 200, and then the packaging operation is performed.

In the manufacturing method of the toilet cleaner 100 described above,
A ply processing step of plying a plurality of base papers not containing a water-soluble binder;
A solution application step of applying a binder solution to the ply-processed sheet;
A drying step of drying the sheet provided with the binder solution;
A winding step of slitting and winding the sheet dried in the drying step to a predetermined width;
Including
In the solution application step, the binder solution is sprayed to the corresponding outer surface from spray nozzles provided corresponding to both outer surfaces of the ply-processed sheet.
In the ply processing step, a plurality of base papers that do not contain a water-soluble binder may be ply-processed, and a plurality of base papers that contain a water-soluble binder may be ply-processed.

  Next, as a result of measuring the chemical solution impregnation rate for the toilet cleaners according to the examples and comparative examples of the present invention, and as a result of measuring the height of the toilet cleaner laminates according to the examples and comparative examples of the present invention. explain.

[Measurement of chemical impregnation rate of toilet cleaner]
Toilet cleaners according to the following examples and comparative examples were prepared.

Example 1
The inner layer sheet is a three-ply sheet using a sheet different from the outer layer sheet, and is specifically as follows.
(Outer layer sheet)
Size: MD direction 340mm, CD direction 230mm
Ingredients: 100% by weight of wood pulp (hardwood bleached kraft pulp: 30% by weight, softwood bleached kraft pulp: 70% by weight)
Per unit weight: 28 g / m ²
Crepe rate: 11.5%
(Inner layer sheet)
Size: MD direction 340mm, CD direction 230mm
Ingredients: 100% by weight of wood pulp (hardwood bleached kraft pulp: 30% by weight, softwood bleached kraft pulp: 70% by weight)
Per unit weight: 30 g / m ²
Crepe rate: 11.5%
(Emboss)
None (medical solution)
Ingredients: 5.0% by weight of ethanol, 0.59% by weight of disinfectant, 0.45% by weight of surfactant, 3.0% by weight of boric acid, 90.96% by weight of water
Chemical solution impregnation rate: 200%
Impregnation method: After folding the sheet, the chemical solution was uniformly impregnated.
(Folding method)
After folding once in the CD direction, it was folded once in the MD direction and quartered. In addition, it folded before chemical | medical solution impregnation.

(Example 2)
Per outer layer sheet, the basis weight and 30g / ^{m 2,} per inner layer sheet, the basis weight and 44g / ^{m 2,} was. Other configurations are the same as those of the first embodiment.

(Comparative Example 1)
The basis weight of the inner layer sheet was 28 g / m ² . Other configurations are the same as those of the first embodiment.

(Comparative Example 2)
The basis weight was 44 g / m ² for the outer layer sheet, and the basis weight was 28 g / m ² for the inner layer sheet. Other configurations are the same as those of the first embodiment.

(Comparative Example 3)
The basis weight of the outer layer sheet was 30 g / m ² . Other configurations are the same as those of the first embodiment.

(Comparative Example 4)
About the outer layer sheet, the basis weight was 30 g / m ² , and the components were 2.6% by weight of PVA fiber and 97.4% by weight of wood pulp (hardwood bleached kraft pulp: 30% by weight, softwood bleached kraft pulp: 70% by weight).
Other configurations are the same as those of the first embodiment.

(Comparative Example 5)
The outer layer sheet has a basis weight of 30 g / m ² and components of 2.6% by weight of PVA fiber and 97.4% by weight of wood pulp (hardwood bleached kraft pulp: 30% by weight, softwood bleached kraft pulp: 70% by weight). On the other hand, the basis weight was 30 g / m ² and the components were wood pulp 100% (hardwood bleached kraft pulp: 30% by weight, softwood bleached kraft pulp: 70% by weight).
Other configurations are the same as those of the first embodiment.

(Test method)
For the toilet cleaners according to the examples and comparative examples, those prepared in both the pre-chemical solution impregnation and after the chemical solution impregnation are prepared. For each of the toilet cleaners, the folded toilet cleaner is opened, and then a fold portion parallel to the CD direction ( A portion in FIG. 4 (a)) and a portion between the creases (B portion in FIG. 4 (a)) are cut so as to be 20 mm in the Y direction and 230 mm in the X direction. The weight was measured and the chemical solution impregnation rate was calculated.
Specifically, for each part A and B of each Example and Comparative Example, after subtracting the weight before impregnation with the chemical solution from the weight after impregnation with the chemical solution, calculating the weight of the impregnated chemical solution, By dividing by the weight of the test piece of the part before impregnation with the chemical solution, the ratio of the weight of the chemical solution impregnated in the test piece after the chemical solution impregnation to the weight of the test piece before the chemical solution impregnation was calculated. Two samples were prepared for each of the examples and comparative examples, and the test was performed twice.

(Test results)
The results of the test are shown in Table I.

(Evaluation)
From comparison between Examples 1 and 2 and Comparative Examples 1 to 3, it can be seen that by increasing the basis weight of the inner layer sheet as compared with the outer layer sheet, the chemical liquid impregnation rate of the fold portion can be increased.
Further, by comparing Comparative Example 4 with Comparative Examples 3 and 5, both sides of the outer layer sheet are formed by a fiber assembly including PVA fibers, and the inner layer sheet is formed of a fiber assembly not including PVA fibers. It turns out that the chemical | medical solution impregnation rate of a crease | fold part can be raised.

[Measurement of height of toilet cleaner laminate]
Toilet cleaner laminates according to the following examples and comparative examples were prepared.

(Example 3)
It is the toilet cleaner laminated body which laminated | stacked 20 toilet cleaners based on Example 1 folded by 1/4 so that the direction of a crease might be aligned.

(Comparative Example 6)
This is a toilet cleaner laminate in which 20 toilet cleaners according to Comparative Example 2 folded in a quarter are stacked so that the direction of the folds is aligned.

(Comparative Example 7)
A toilet cleaner laminate in which 20 toilet cleaners according to Comparative Example 3 folded in a quarter are stacked so that the direction of the folds is aligned.

(Comparative Example 8)
This is a toilet cleaner laminate in which 20 toilet cleaners according to Comparative Example 4 folded in a quarter are stacked so that the direction of the folds is aligned.

(Test method)
About the toilet cleaner laminated body which concerns on an Example and a comparative example, the side (the C part in FIG. 9) in which the fold which folded the second time was formed in the state mounted on the base with which the upper surface became a horizontal surface, and For the opposite side (side where no crease is formed; D portion in FIG. 9), the height from the upper surface of the placed table to the top of the toilet cleaner laminate was measured. Three samples were prepared for each of the examples and comparative examples, and three tests were performed.

(Test results)
The test results are shown in Table II.

(Evaluation)
By comparing Example 3 with Comparative Examples 6 and 7, by forming a toilet cleaner laminate using a sheet in which the basis weight of the inner layer sheet is higher than that of the outer layer sheet, the end where the folds are formed It can be seen that the difference in height between the portion and the end portion where the crease is not formed can be suppressed.
Further, in comparison with Comparative Example 7 and Comparative Example 8, both sides of the outer layer sheet are formed by a fiber assembly containing PVA fibers, and the inner layer sheet is a toilet using a sheet formed by a fiber assembly not containing PVA fibers. It can be seen that by forming the cleaner laminate, the difference in height between the end where the fold is formed and the end where the fold is not formed can be suppressed.

  As mentioned above, although this invention was concretely demonstrated based on embodiment, this invention is not limited to the said embodiment, It can change in the range which does not deviate from the summary.

In the description of the embodiment of the present invention, the binder solution is applied by a spray method. However, a doctor chamber method (one of the continuous dry base paper 1A continuously fed from the primary raw roll 1 is used. A transfer facility comprising two plate rolls paired with a backup roll, an anilox roll paired with each plate roll, and a doctor chamber for applying a chemical to each anilox roll), and / or 3 Roll system (two plate rolls paired with one backup roll, anilox roll paired with each plate roll, a dip roll that applies a chemical to each anilox roll, and a chemical on the dip roll The binder solution may be applied by a transfer facility equipped with a pan for imparting a stencil. That is, in the method for producing a water-decomposable sheet obtained by plying a plurality of base papers (continuous dry base paper 1A), out of a plurality of base papers that do not contain a water-soluble binder, A solution application step of applying (transferring) a binder solution to at least one of the surfaces; a ply processing step of plying the plurality of base papers; a drying step of drying the ply-processed sheet; and the drying step A winding step for slitting and winding the sheet dried in a predetermined width, and the solution application step corresponds to at least one of the surfaces of the base paper as the front surface and the back surface of the water-decomposable sheet The binder solution is transferred from the provided printing machine to the corresponding base paper.
In the solution application step, among the plurality of base papers that do not contain a water-soluble binder, the binder solution is applied to at least one surface of the base paper as the front and back surfaces of the water-decomposable sheet, and the water-soluble binder is water-soluble. You may make it provide a binder solution with respect to at least any one surface of the base paper used as the surface of a water-decomposable sheet and a back surface among several base paper containing a binder.

In mere roll transfer, in order to apply a desired amount of a chemical solution, a very high concentration chemical solution is required, and since this chemical solution has a high viscosity, it cannot be uniformly transferred by roll transfer. Further, if the concentration is lowered in order to lower the viscosity, the desired applied amount cannot be obtained as described above. As described above, since it is extremely difficult to apply a chemical to the dried base paper, a doctor chamber method and / or a three-roll method is adopted.
By adopting a doctor chamber method or / and a three-roll method in which a pair of printing plate rolls is provided for one backup roll, a sufficient amount of chemical solution is applied to each printing plate roll at least in the total amount. Can be applied to the dried base paper. Further, since there is only one backup roll, it can be applied extremely uniformly. This is because the tension between the first printing roll and the next printing roll is extremely stable and constant because there is only one backup roll. However, the chemical solution can be applied to the continuous base paper very uniformly. In addition, since the interval between the two printing plate rolls is shortened, even after the chemical solution is applied on the first printing plate roll and then applied on the next printing plate roll, uniform transfer can be performed without uneven application. It is. Such an effect cannot be obtained simply by making the backup roll and the plate roll into a pair of two stages.

More preferably, the chemical solution is applied by the doctor chamber method because the chemical solution can be transferred more uniformly and stably in the width direction than the three-roll method.
Furthermore, it has the drying process which dries the continuous paper to which the chemical | medical solution was provided. This drying process is preferably indirect drying without direct contact with the continuous paper, particularly by infrared irradiation. In the case of indirect drying, generation of wrinkles is suppressed. In particular, if it is caused by infrared irradiation, drying of the various portions of the paper surface occurs uniformly, so that generation of wrinkles and distortion during drying can be effectively prevented.
The doctor chamber method will be described in detail below as an example.

In this doctor chamber type transfer equipment, one plate roll is provided for one backup roll.
The coating processing speed when applying the binder solution is 30 to 100 m / min, and more preferably 50 to 80 m / min. If it is less than 30 m / min, the crepe stretches before being dried, and there is a problem that it is difficult to process in a subsequent process. On the other hand, when the amount exceeds 100 m / min, a sufficient transfer amount cannot be obtained, or variation in wet strength and water disintegration occurs due to variation in the coating amount in the width direction.

  The diameter of the backup roll is suitably 250 to 420 mm. When the diameter is less than 250 mm, the contact area between the printing plate roll and the backup roll is reduced, and stable coating cannot be performed. Even if the diameter exceeds 420 mm, there is no problem in manufacturing, but it is not preferable because the equipment cost is excessive.

  The printing plate roll is provided with an anilox roll for delivering a binder solution thereto, and a doctor chamber for delivering the binder solution to the anilox roll for application thereto is provided. For the doctor chamber, a snake pump that delivers the binder solution to the doctor chamber is installed on both the feed and return to feed the anilox roll solution pan. High binder solution transfer is possible.

The continuous dry base paper 1A fed out from the primary raw roll 1 is wound around a backup roll through an appropriate guide roll, and given appropriate tension and surface stability.
Then, the binder solution is roll-transferred by the printing plate roll to the continuous dry base paper 1A wound around the backup roll.
Here, the printing plate roll is a solid roll with no concave grooves, and a binder solution is applied to the entire continuous dry base paper 1A as in solid printing. The seamless roll used as the printing plate roll is formed by winding a rubber plate around a sleeve of a type roll, putting it in a kettle, performing overheating welding, and polishing. The rubber plate used as the material can be selected in material, hardness, color and the like according to a predetermined purpose.

On the other hand, the number of lines and the cell capacity of the anilox roll delivering the binder solution to the printing plate roll are 60 to 120 lines / inch and the cell capacity is 40 to 90 ml / m ² depending on the concentration of the binder solution. Is desirable. If the number of lines is less than 60 lines / inch, an excessive binder solution is transferred to the printing plate roll, and as a result, the binder solution may be applied to the continuous dry base paper 1A with unevenness from the printing plate roll. Rise. On the other hand, when the number of lines exceeds 120 lines / inch, it becomes difficult to deliver a sufficient amount of the binder solution to the entire peripheral surface of the printing plate roll. Further, if the cell capacity is less than 40 ml / m ² , it becomes difficult to deliver a sufficient amount of the binder solution to the printing plate roll, and even if the cell capacity exceeds 90 ml / m ² , only the yield is deteriorated. .
Note that the continuous dry base paper 1A to which the binder solution is applied (transferred) as described above targets only the base paper that is the uppermost layer or the lowermost layer when plying. That is, for example, in the case of three-ply processing, the binder solution is not applied (transferred) to the continuous dry base paper 1A serving as the middle layer.

In the doctor chamber method, the binder solution is transferred to the continuous dry base paper 1A, that is, the binder solution is transferred to the continuous dry base paper 1A before the ply processing step. Thereafter, the binder solution may be transferred to the ply continuous ply sheet 1B.
That is, in a method for producing a water-degradable sheet obtained by plying a plurality of base papers (continuous dry base paper 1A), a ply processing step of plying a plurality of base papers not containing a water-soluble binder, and a ply-processed sheet A solution application step for applying (transferring) the binder solution to the sheet, a drying step for drying the sheet provided with the binder solution, and a winding step for slitting and winding the sheet dried in the drying step to a predetermined width. And the solution applying step transfers the binder solution to a corresponding outer surface from a printing machine provided corresponding to the outer surface of at least one of the ply-processed sheets.
In the ply processing step, a plurality of base papers that do not contain a water-soluble binder may be ply-processed, and a plurality of base papers that contain a water-soluble binder may be ply-processed.
Thus, when transferring a binder solution by a doctor chamber system, since a binder solution with high viscosity can be apply | coated, it can suppress that a binder solution osmose | permeates the inside of a sheet | seat. Therefore, CMC can be fixed only on the sheet surface. In addition to the case where the binder solution is transferred by the doctor chamber method, for example, the binder surface may be coated on the sheet surface by a coater for hot melt resin coating. In such a case, it is possible to fix the CMC only on the sheet surface.

In the description of the embodiment of the present invention, the binder solution is applied in the solution application process of the solution application equipment shown in FIG. 6, but the binder solution may be applied in the paper making process. Good.
That is, in the method for producing a water-decomposable sheet obtained by plying a plurality of base papers (continuous dry base paper 1A), the paper making process includes making a plurality of base papers, and the paper making process is performed on wet paper being made. To apply a binder solution.

Specifically, in the paper making process, for example, the wet paper formed by the paper making net is transported on the felt, and the wet paper on the felt is transferred to the Yankee dryer via the touch roll. The wet paper is dried to obtain a base paper in the process of being attached and conveyed, and the binder solution is sprayed from the spray nozzle onto the wet paper immediately after being transferred onto the above-mentioned Yankee dryer.
Thus, when the binder solution is applied even in the paper making process, the strength of the entire water-decomposable sheet obtained can be increased, and the surface of the water-decomposable sheet can be obtained by further applying the binder solution in the subsequent solution applying process. The strength can be further increased.

  In addition, the detailed configuration of the toilet cleaner 100 can be changed as appropriate without departing from the spirit of the present invention.

[Explanation of terms]
The following terms in the specification shall have the following meanings unless otherwise specified.
(Chemical solution impregnation rate)
The mass of the sheet before impregnation with the chemical solution and the mass of the chemical solution to be impregnated are measured, and the ratio of the mass of the chemical solution to be impregnated to the mass of the sheet before impregnation with the chemical solution is calculated.
(Weight)
It refers to the basis weight measured according to JIS P 8124: 2011.
(Length of sheet, emboss, etc.)
This refers to the length measured in a state where the water-decomposable sheet is placed on a flat surface in a state where no tension is applied.
(Crepe rate)
{(Peripheral speed of the dryer during papermaking) − (reel peripheral speed of the reel device in the winding means)} / (peripheral speed of the dryer during papermaking) × 100.

100 Toilet cleaner 200 Toilet cleaner laminate EM11 Emboss P Base paper sheet P1 Outer sheet P2 Inner sheet

Claims (9)

A water-degradable sheet in which a plurality of base paper sheets are laminated and impregnated with a chemical solution,
The base paper sheet includes an outer layer sheet disposed on the front and back surfaces of the water-decomposable sheet, and an inner layer sheet disposed between the outer layer sheets,
The water-decomposable sheet, wherein the basis weight of the inner layer sheet is higher than the basis weight of the outer layer sheet. ^2. The water-decomposable sheet according to claim 1, wherein the basis weight of the inner layer sheet is 0.5 g / m ² or more and 20 g / m ² or less higher than the basis weight of the outer layer sheet.   The water-decomposable sheet according to claim 1 or 2, wherein the outer layer sheet contains polyvinyl alcohol fibers.   The water-decomposable sheet according to claim 3, wherein the outer layer sheet contains 2.0% by weight or more and 4.0% by weight or less of polyvinyl alcohol fiber.   The water-decomposable sheet according to any one of claims 1 to 4, wherein the outer layer sheet is creped.   The outer layer sheet and the inner layer sheet are creped, and the crepe rate of the outer layer sheet is 0.5% to 17% higher than the crepe rate of the inner layer sheet. The water-decomposable sheet according to any one of 4 to 4.   The water-decomposable sheet according to any one of claims 1 to 6, wherein an emboss is formed on the entire surface of the base paper sheet.   A water-decomposable sheet laminate in which a plurality of the water-decomposable sheets according to any one of claims 1 to 7 which are folded a predetermined number of times are laminated so that the direction in which folds are formed is common.   The water-decomposable sheet laminate according to claim 8, wherein the water-decomposable sheet is folded only once in the MD direction and the CD direction.

Images