JP2020108825A - Manufacturing method of toilet roll - Google Patents

Abstract

To provide a long toilet roll whose touch feeling is excellent, and core is hardly collapsed, without impairing a cost and productivity.SOLUTION: A toilet roll 10 is obtained by winding in a roll state, 1-ply toilet tissue paper 10x having a plurality of irregularities in which one surfaces are projections and corresponding opposite surfaces are recesses. The toilet roll is such that: a winding length is 105-210 m; a winding diameter is 100-140 mm; a roll mass not including a core per roll width of 114 mm is 225-485 g; a roll mass of the core per roll width of 114 mm is 3.2-6.0 g; an external diameter of the core is 25-48 mm; and a roll density of the roll is 0.17-0.35 g/cm3.SELECTED DRAWING: Figure 1

Description

The present invention relates to a toilet roll wound with 1-ply toilet paper.

The toilet paper is commercially available, which is mainly packaged in units of 4 rolls or 12 rolls. Since these packages are bulky, the amount that can be carried at the time of purchase is limited, and the amount that can be purchased at one time is naturally limited. In addition, storage space is limited at home, workplace, public facilities, etc.
Under these circumstances, a toilet roll having a long wrap length (patent documents 1 and 2) has been developed in which the basis weight of each sheet of toilet paper is reduced to 14 g/m ² or less (Patent Documents 1 and 2). ..
Further, the applicant of the present application has developed a toilet roll having a long roll length while improving the texture and the feeling of use by making the basis weight of each toilet paper higher than 13 g/m ² (Patent Documents 3 and 4). ).

JP 2006-087703 JP JP 2013-208297 JP JP-A-2014-188342 JP-A-2014-233363

By the way, generally, a toilet roll has a product length of several meters and a width of several meters. Manufacturing.
On the other hand, to make a long toilet roll with a limited winding diameter, it may be wound tightly, but if it is wound too tightly, the core will be crushed when it is cut by a log saw. In addition, when the sheet of toilet paper is not provided with embossments, the sheet is tightly wound because there is no void between the sheets, and the feel is poor. Of course, if the toilet roll is softly wound, the core will not be crushed even if it is cut with a log saw, but the winding diameter becomes large and it becomes difficult to mount it on the paper holder.

On the other hand, if the log is wound in the product width, the cutting of the log saw becomes unnecessary and the problem that the core is crushed is solved, but this method cannot be adopted because the productivity is significantly reduced.
Also, if the core diameter is increased, the slack of the sheet is less likely to occur at the beginning of winding the sheet (where it is wound around the core) during log production, so it is possible to increase the processing speed and improve the productivity. It is easy to collapse.

On the other hand, when using a toilet roll that does not use the core, the core will not be crushed, but the amount of glue used at the beginning of the sheet tends to be uneven, and when used until the end of the sheet (Part of) is hard and does not come loose, making it difficult to unwind. Also, if the core has a small diameter, it becomes difficult to mount it on the toilet holder.
Further, when the mass of the core is increased (the basis weight of the core is increased), the core is less likely to be crushed, but the core becomes hard, which lowers the productivity of the core and increases the cost.
As described above, when manufacturing a long toilet roll having a core, it is difficult to prevent the core from being easily crushed without impairing cost and productivity.

Therefore, it is an object of the present invention to provide a long toilet roll which has a good tactile sensation and which does not easily crush the core without impairing cost and productivity.

The present inventors have found that when manufacturing a toilet roll, the winding density of the roll is important as a factor that makes it difficult for the core to be crushed. In other words, if the winding density is too high, the core will be solidly wound (mass per volume is high) and the core will be easily crushed, while if the winding density is low, the core will not be crushed, but the winding diameter will be large and the toilet paper holder etc. It becomes difficult to fit in.
In addition, by defining the mass of the core, it is possible to prevent the productivity of the core from decreasing and the cost from increasing, and by defining the outer diameter of the core, the productivity of the toilet roll is improved while preventing the core from being crushed. ..

In order to solve the above-mentioned problems, the toilet roll of the present invention is a toilet roll obtained by winding a 1-ply toilet paper roll having a plurality of irregularities in which one surface is a convex portion and the corresponding opposite surface is a concave portion. Then, the roll length is 105 to 210 m, the roll diameter is 100 to 140 mm, the roll mass not including the core per roll width 114 mm is 225 to 485 g, and the mass per core width per 114 mm is 3.2 to 6.0 g. The outer diameter of the core is 25 to 48 mm, and the winding density of the roll is 0.17 to 0.35 g/cm ³ .

The depth of the concave and convex portions is preferably 0.01 to 0.40 mm.
It is preferable that the core has a hardness of 0.7 to 3.6 mm.
The apparent basis weight of the core is preferably 250 to 450 g/m ² .
The ratio represented by (hardness of the core)/(winding density of the roll) is preferably 2.0 to 11.5 mm/(g/cm ³ ).
It is preferable that the tensile strength DMDT in the longitudinal direction of the toilet paper when dried according to JIS P8113 is 2.5 to 7.0 N/25 mm.
It is preferable that the tensile strength DCDT of the above-mentioned toilet paper in the dry direction based on JIS P8113 is 0.7 to 2.2 N/25 mm.
The unevenness is preferably embossed.

According to the present invention, it is possible to obtain a long toilet roll having a good tactile sensation and a core that is hard to be crushed without impairing cost and productivity.

It is a perspective view showing appearance of a toilet roll concerning an embodiment of the present invention. It is sectional drawing which shows the embossing provided in the roll front surface and the back surface. It is a figure which shows an example of a roll winding processing machine. It is a figure which shows the measuring method of the embossing depth. It is another figure which shows the measuring method of the embossing depth. It is a figure following FIG. It is a figure which shows an example of a machine winder. It is a figure which shows the measurement of the embossing depth in case an embossing is connected in the flow direction (MD direction).

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, preferred embodiments of the present invention will be described, but these are provided for the purpose of illustration and do not limit the present invention.
As shown in FIG. 1, a toilet roll 10 according to an embodiment of the present invention is a toilet roll in which a 1-ply toilet paper 10x having a plurality of irregularities is wound around a core 5 in a roll shape, and a roll length ( The winding length) is 105 to 210 m, the winding diameter DR is 100 to 140 mm, the roll mass not including the core 5 per roll width 114 mm is 225 to 485 g, and the mass of the core 5 per roll width 114 mm is 3.2 to 6. 0.0 g, and the outer diameter of the core 5 is 25 to 48 mm.
The surface of the toilet paper 10x outside the roll is the roll surface (or the surface of the toilet paper) 10a, and the inside surface of the roll is the roll back surface (or the back surface of the toilet paper) 10b.

If the roll length of the toilet roll 10 is less than 105 m, the roll length per roll becomes short, and space saving during storage cannot be achieved. If the roll has a roll length of more than 210 m, the roll diameter DR becomes too large and it is difficult to fit the roll in a toilet paper holder or the like.
The winding length is preferably 130 to 190 mm, more preferably 150 to 170 mm.

If the winding diameter DR is less than 100 mm, the winding length will be less than 105 m. If the winding diameter DR exceeds 140 mm, it will be difficult to fit in a toilet paper holder or the like.
The winding diameter DR is preferably 108 to 135 mm, more preferably 115 to 123 mm.

The roll mass per roll width W of 114 mm not including the core (winding core) 5 is 225 to 485 g. Here, when the roll width W is different from 114 mm, W is converted to 114 mm to obtain the roll mass. For example, when the roll width W is 105 mm, the mass obtained by multiplying the roll mass by a coefficient (114/105) is the roll mass per 114 mm W.
When the roll mass is less than 225 g, the winding length per roll becomes short and the roll replacement frequency increases. If the roll mass exceeds 485 g, the roll diameter becomes large and it becomes difficult to fit the roll in the toilet paper holder.
The roll mass is preferably 255 to 425 g, more preferably 295 to 365 g.

The mass of the core 5 per roll width W of 114 mm is 3.2 to 6.0 g. The method for converting the mass of the core 5 when the roll width W is different from 114 mm is as described above.
When the mass of the core 5 is less than 3.2 g, the basis weight of the core 5 is small, and the core is likely to be crushed during the manufacturing of the toilet roll (log). When the mass of the core 5 exceeds 6.0 g, the grammage of the core 5 becomes high, so that the core is less likely to be crushed, but the core becomes hard and the productivity of the core is lowered, and the cost is increased.
The mass of the core 5 is preferably 4.0 to 5.5 g, and more preferably 4.5 to 5.0 g.

The outer diameter of the core 5 is 25 to 48 mm. When the outer diameter of the core 5 is less than 25 mm, the core is less likely to be crushed, but it is difficult to mount the toilet roll on the toilet holder. When the outer diameter of the core 5 exceeds 48 mm, the core is likely to be crushed during manufacturing of the toilet roll (log).
The outer diameter of the core 5 is preferably 35 to 46 mm, more preferably 37 to 43 mm.

The winding density of the roll is 0.17 to 0.35 g/cm ³ , preferably 0.20 to 0.33 g/cm ³ , and more preferably 0.25 to 0.31 g/cm ³ .
If the roll is wound too tightly (the winding density is too high), the core will be tightly wound (mass per volume is high) and the core will be easily crushed. On the other hand, if the roll is wound too weakly, the embossing will not collapse, but the winding diameter will become large, making it difficult to mount on the paper holder, or the winding force for the inner winding will be too weak, and There is a risk that the product will pop out and a defective product will occur. Therefore, the winding density is defined as a factor for expressing the winding strength of the roll.

The winding density is represented by (roll mass not including core)/(roll volume). The roll mass is the mass of the toilet roll 10 converted when the roll width W is 114 mm. The roll volume is represented by [{cross-sectional area of roll outer diameter (rolling diameter DR) portion}-(cross-sectional area of core outer diameter portion)}×roll width (114 mm). For example, when the roll mass per roll width of 114 mm is 328 g, the winding diameter is 118 mm, and the outer diameter of the core is 39 mm, the winding density is 328 g/[{3.14×(118 mm÷2/10) ² −3.14×( 39 mm÷2÷10) ² }×(114 mm÷10)]=0.30 g/cm ³ .
When the winding density is less than 0.17 g/cm ³ , the winding diameter DR exceeds 140 mm, which makes it difficult to fit in a toilet paper holder or the like, and the winding force for the inner winding becomes too weak, so that the inner winding side of the roll is There is a risk that the product will protrude in the axial direction (poor shape retention of the roll) and become a defective product. When the winding density exceeds 0.35 g/cm ³ , the core is tightly wound and the core is easily crushed. In addition, the softness of the sheet may be poor, or the emboss provided on the toilet paper may be crushed, resulting in deterioration of the cosmetic appearance during use.

<Roughness>
The toilet roll 10 (toilet paper 10x) of the present invention has a plurality of irregularities. This unevenness can be provided by, for example, embossing. In the present invention, since the sheet is 1 ply, single embossing is performed. Of course, a known double-height embossing roll can be used, or single embossing can be performed multiple times. In addition, the emboss pattern (emboss size, depth, number, area ratio) can be appropriately changed.
Hereinafter, embossing will be described as an example of the unevenness.
As shown in FIG. 3, the single emboss is formed by pressing the embossed protrusion of the embossing roll 151 only from one surface of the toilet paper 10x.
FIG. 2 is a cross-sectional view showing the single embossing 2 provided on the toilet roll 10 (toilet paper 10x). In the example of FIG. 2, the toilet paper 10x is made of one ply, and the upper portion of FIG. 2 corresponds to the roll surface 10a side. The embossing (single embossing) 2 in which the concave portion 2R and the convex portion 2P appear on the back surface is formed on the surface (front surface in FIG. 2) of the toilet paper 10x against which the embossing roll 151 is pressed.
2A shows the case where the embossing depth is deep, and FIG. 2B shows the case where the embossing depth is shallow.

In this case, the paper thickness t2 of the toilet paper 10x after embossing is the same (this paper thickness reflects the distance between the non-embossed portion on the front surface of the toilet paper 10x and the convex portion 2P of the embossed surface on the back surface). However, the sheet shown in FIG. 2A in which the base paper is thinned to a paper thickness t1 by calendering and is embossed so that the emboss depth (corresponding to the depth of the concave and concave portions) D is deeper is the sheet. Is soft and has an excellent texture. This is probably because the embossed unevenness shown in FIG. 2(a) has a higher bulk (lower density) with respect to the paper thickness of the base paper, is easily deformed, and improves the softness of the sheet. ..
Further, in the case of FIG. 2A, in order to increase the embossing depth D, it is necessary to reduce the paper thickness t1 per sheet to make the unevenness noticeable. The softness of the sheet is improved by virtue of strongly performing.
Of course, the embossing process may be performed without performing the calendar process. In this case, the paper thickness of the sheet before the embossing treatment can be controlled by the pulp composition, the beating condition, the crepe ratio, etc. so that the embossing depth can be secured.

On the other hand, if the surface of the toilet paper 10x is made smooth without embossing, the surface is too smooth and the surface feels crispy, and the softness of the sheet is poor. If the embossed recess 2R is provided on the outside of the roll (on the roll surface 10a side) of the toilet paper 10x where water tends to adhere when the toilet seat is washed with warm water, the recess 2R has a better feel than the protrusion. The softness of the sheet is improved.

Further, the means for ensuring the softness of the toilet paper (sheet) 10x is not limited to embossing as long as it gives unevenness to the surface, and for example, unevenness may be applied to the web at the time of paper making by using an uneven fabric. Good. Further, in this case, the depth of the concave and convex portions is preferably set to a range corresponding to the emboss depth D.

Further, the depth D of the concave and convex portions is obtained by measuring with a microscope.
As the microscope, a product name “One-shot 3D measurement macroscope VR-3100” manufactured by KEYENCE can be used. The product name "VR-H1A" can be used as software for observing, measuring, and analyzing images on a microscope. Further, the measurement conditions are such that the magnification is 12 times and the visual field area is 24 mm×18 mm. The measurement magnification and the field of view may be appropriately changed depending on the size of the emboss to be obtained.

First, as shown in FIG. 4, the longest part a of the embossed peripheral edge fr is obtained. FIG. 5A shows a height profile on the XY plane by the microscope, and it can be seen that the height of the toilet paper surface is expressed by shading. Dark portions in FIG. 5A indicate individual embosses 2, and the longest part a of one emboss 2 can be discriminated from FIG. 5A. By drawing a line segment AB crossing the longest part a, a height (measurement sectional curve) profile of the embossing 2 is obtained as shown in FIG. 5B. Here, since the convex portion (non-embossed portion) and the concave portion of the emboss can be identified by the shade of the color of the XY plane image, the line segment AB can be determined so that the convex portion and the concave portion cross the adjacent portion. Good.

Here, the height profile in FIG. 5B is a (measurement) cross-sectional curve S representing the unevenness of the sample surface of the actual toilet paper, but noise (there is a fiber lump on the surface of the toilet paper, fibers are It also includes a sharp peak due to a beard-like extension or a portion without fibers), and it is necessary to remove such a noise peak when calculating the height difference of the unevenness.
Therefore, as shown in FIG. 6, a “contour curve” W is calculated from the cross-sectional curve S of the height profile, and two inflection points P1 and P2 that are convex upward in this contour curve W and the inflection The minimum value sandwiched between the points P1 and P2 is obtained and is set as the minimum depth value Min. Further, the average value of the depth values of the inflection points P1 and P2 is set as the maximum depth value Max.

In this way, the depth D of the concave and convex portions is set to the maximum value Max-the minimum value Min. Further, the distance (length) of the inflection points P1 and P2 on the XY plane is defined as the length of the longest part a. The "contour curve" is a wavelength shorter than λc: 800 μm (where λc is a "filter that defines the boundary between the roughness component and the waviness component" described in JIS-B0601 "3.1.1.2") from the cross-section curve. It is a curve obtained by removing a component of surface roughness by a low pass filter. If λc is set to be equal to or larger than the interval P1 between adjacent embosses (this is referred to as an emboss pitch), the peak may be recognized as noise. Therefore, λc is set to be less than the emboss pitch. For example, when the emboss pitch is 800 μm or less, for example, λc:250 μm is set. As for the interval of P1 between adjacent embosses, P1 and P2 are similarly obtained for the next emboss connected to the left or right of FIG. 6, and the interval of two P1 when the adjacent embosses are aligned with P1, P2, and P1. is there.

Similarly, in FIG. 5A, the depth D of the concave and convex portions of the concave and convex is measured also for the longest portion b in the direction perpendicular to the longest portion a, and The larger value is adopted as the depth D of the concave and convex portions. The above measurement is performed for any ten embosses 2 on the surface 10a of the toilet paper 10x, and the average value thereof is adopted as the final depth D of the concave and convex portions.
However, as shown in FIG. 8, when the embossing 2 is connected in the flow direction (MD direction), the longest part a becomes the same as the winding length, and the height difference cannot be obtained, and the depth D of the recess is reduced. I can't measure. Therefore, the line segment AB can be drawn across the emboss 2 in the width W direction orthogonal to the direction in which the emboss 2 is connected (MD direction), and the depth D of the recess can be measured.
Similarly, when the embossing 2 is connected in the width W direction (CD direction), a line segment AB is drawn so as to straddle the embossing 2 in the flow direction (MD direction), and the depth D of the recess is measured.

When measuring the depth D of the concave and convex portions, the measurement surface is on the surface 10a side.
Further, when determining the depth D of the concave and convex portions of the concave and convex, when selecting any 10 embossing (concavo-convex) 2, from the end of the outer roll of the toilet roll 10 (the position to start using the toilet paper), At a portion corresponding to 10% of the roll length of the toilet roll 10 (for example, when the roll length is 150 m, a portion of 150 m×10%=15 m from the end), any 10 of the embosses 2 arranged along the width direction Choose. Further, when there are less than 10 embosses 2 in the width direction W, an insufficient number of embosses may be selected from the group of embosses 2 on the outer winding side or the inner winding side adjacent to the embossing 2. When the emboss 2 to be measured hits the perforation, the group of the emboss 2 on the outer winding side adjacent to the perforation is measured.

The depth D of the concave and convex portions is preferably 0.01 to 0.40 mm, more preferably 0.03 to 0.30 mm, still more preferably 0.04 to 0.23 mm.
When the depth D is smaller than the above range, the degree of unevenness is small and the bulk is low (density is high), and it may be difficult to improve the softness of the sheet. When the depth D exceeds the above range, the unevenness becomes too conspicuous and the bulk becomes too high (the density becomes too low), the winding diameter DR becomes too large, and it becomes difficult to mount the toilet roll 10 on the paper holder. There is.

The hardness of the core 5 is preferably 0.7 to 3.6 mm, more preferably 1.0 to 2.8 mm, and further preferably 1.4 to 2.1 mm.
If the hardness of the core is less than 0.7 mm, the productivity of the core may be poor. This is because the strength becomes too high due to the high basis weight of the core, etc., and it becomes difficult to bend the core sheet into a tubular shape. When the hardness of the core is more than 3.6 mm, the core may be crushed when the toilet roll is manufactured. This is because the strength is too low due to the low basis weight of the core and the core is easily crushed.

The hardness of the core 5 is measured as follows using a compression tester (Handy compression tester KES-G5 manufactured by Kato Tech Co., Ltd.). First, the core 5 is placed sideways on a hard table so that the axis is horizontal. Next, the above KES-G5 compressor (area 2.0 cm ² ) is pressed into the center of the outer surface of the core 5 from above at a speed of 10 mm/min. (Tm-T0) is the hardness of the core 5 where T0 is the indentation depth when the pressure of the compressor pushing the roll is 0.5 gf/cm ² and Tm is the indentation depth when the pressure is 250 gf/cm ^2. To do. If this value is large, it means that the core is likely to be crushed. The measurement is performed 5 times using 5 cores (1 core is measured once), and the measurement results are averaged.

The ratio represented by (hardness of the core)/(winding density of the roll) is preferably 2.0 to 11.5 mm/(g/cm ³ ), and more preferably 3.1 to 8.5 mm/(. g/cm ³ ), and more preferably 4.5 to 6.5 mm/(g/cm ³ ).
When the winding density is within the above range and the ratio is less than 2.0 mm/(g/cm ³ ), the hardness of the core with respect to the winding density is low, and the strength of the core is higher than necessary. May increase the cost of the core.
When the winding density is within the above range and the ratio exceeds 11.5 mm/(g/cm ³ ), the hardness of the core with respect to the winding density is high and the core may be easily crushed.

The apparent mass of the core 5 is preferably 250 to 450 g/m ² , more preferably 300 to 400 g/m ² , and further preferably 320 to 350 g/m ² . When the apparent mass of the core 5 is less than 250 g/m ² , the core may be crushed when the toilet roll is manufactured. On the other hand, when the apparent mass of the core 5 exceeds 450 g/m ² , the strength of the core becomes unnecessarily high, which may increase the cost of the core or reduce the productivity of the core.
The apparent basis weight of the core is represented by (mass of core)÷(outer surface area of core). The mass and outer surface area of the core are the mass and outer surface area of the core converted per roll width of 114 mm. For example, when the mass of the core per roll width of 114 mm is 4.7 g and the outer diameter of the core is 39 mm, the apparent basis weight of the core=4.7÷{(3.14×39 mm/1000)×(114 mm/1000 )}=337 g/m ² . Here, the core is usually made by adhering two core base papers with an adhesive or the like, and there is also a part where the two core base papers partially overlap and become thicker. Since it is different from the rolled one, the "apparent" basis weight was used.

The sheet (toilet paper) 10x preferably has a dry machine direction tensile strength (DMDT) DMDT (Dry Machine Direction Tensile strength) of 2.5 to 7.0 N/25 mm, and more preferably 3.0, according to JIS P8113. ˜5.8 N/25 mm, more preferably 3.5-4.5 N/25 mm.
The DMDT is a strip shape having a length of 250 mm in the MD direction (longitudinal direction perpendicular to the width W) of the sheet (toilet paper) 10x, and a test piece having a width W of 25 mm is cut out and measured. The distance between the grips of the tensile tester is set to 100 mm, and the measurement is performed by pulling in the MD direction at a pulling speed of 300 mm/min. At this time, the perforation should not be included in the region where the distance between the grips is 100 mm.

The dry cross direction tensile strength (DCDT) of the toilet paper 10x in the dry direction (CD) based on JIS P8113 is preferably 0.7 to 2.2 N/25 mm, more preferably 0.8 to 1. It is 8 N/25 mm, more preferably 1.0 to 1.5 N/25 mm.
The DCDT is a strip shape having a length of 114 mm (sheet width) in the CD direction (longitudinal direction parallel to the width W) of the sheet (toilet paper) 10x, and a test piece having a width W of 25 mm is cut out and measured. To do. The distance between the grips of the tensile tester is set to 100 mm, and the measurement is performed by pulling in the CD direction at a pulling speed of 300 mm/min. When the roll width (sheet width) is small and 114 mm cannot be secured, the length of the test piece may be used as the roll width. If the roll width (sheet width) is too small to secure a space between grips of 100 mm, this space is defined as {(roll width)-(length to hold sheet with grip x 2)} mm. Is also good.

When DMDT or DCDT is less than the above value, it may be easily shaken and not suitable for practical use. If DMDT or DCDT is higher than the above value, the sheet becomes hard and the softness of the sheet may be impaired.
The flow direction of the toilet paper is defined as "longitudinal direction" and the direction perpendicular to the flow direction is defined as "transverse direction".

The basis weight of each sheet of the toilet paper 10x is preferably 15 to 23 g/m ² , more preferably 17 to 21 g/m ² , and further preferably 18 to 20 g/m ² .
The sheet thickness of the sheet is preferably 0.40 to 1.10 mm/10 sheets, more preferably 0.50 to 0.90 mm/10 sheets, still more preferably 0.60 to 0.85 mm/10 sheets.
It is preferable to set the basis weight and the paper thickness of the sheet within the above ranges, because it becomes easy to adjust the winding length and the winding diameter DR within the above ranges. In addition, the touch feeling when using the toilet paper is improved.
As a method for adjusting the basis weight and the paper thickness of the sheet within the above ranges, the calender conditions (paper thickness and specific volume after calender treatment) and embossing conditions of the base paper web are specified.

When the basis weight of each sheet of the toilet paper 10x is less than 15 g/m ² or the paper thickness is less than 0.40 mm/10 sheets, the strength is reduced and the feeling of use (bulkness) is also reduced. There are cases. When the grammage per sheet of the toilet paper 10x exceeds 23 g/m ² or the paper thickness exceeds 1.10 mm/10 sheets, the toilet paper becomes thick and the roll diameter DR of the roll exceeds 140 mm. It may be difficult to fit in the paper holder.

The specific volume of the toilet paper is preferably 2.8 to 6.5 cm ³ /g, more preferably 3.1 to 5.5 cm ³ /g, still more preferably 3.4 to 4.5 cm ³ /g.
If the specific volume is less than 2.8 cm ³ /g, the softness of the sheet may be poor, or the bulk (bulkness) may be reduced, resulting in poor moisture absorption. On the other hand, when the specific volume exceeds 6.5 cm ³ /g, the bulk (bulkness) of the sheet increases, but the paper thickness increases and the winding diameter may increase.

FIG. 3 shows an example of the roll winding machine 150. The base paper roll is calendered to be a raw fabric 114 (sheet thickness t1). The original fabric 114 is set on the roll winding machine 150, subjected to single embossing by the embossing unit (embossing roll) 151, and then wound on the wide toilet paper roll 10W having the above-mentioned winding diameter by the winding mechanism 153. Taken and logged. After that, the original roll 10W is cut into a predetermined width (114 mm or the like) with a log saw to form the toilet roll 10.
The roll winding machine 150 is roughly classified into two types, a surface type and a center type. The surface method is a method in which the winding roll is wound while being supported from the outside by a plurality of other driving rolls, and the wound roll of the wound toilet roll 10 is easy to control and the production speed becomes higher. The center system is a method of winding by driving a shaft passing through the center of the winding roll, and the wound toilet roll 10 becomes a relatively soft product and is suitable for a product with delicate embossing. In the present invention, the winding can be performed by any method, but the surface method is preferable.
The roll winder 150 is equipped with the machine winder 100 shown in FIG. 7, or the roll winder 150 is equipped with both (2 stacks) or one (1 stack) of the calendars 101 and 102 to perform roll winder processing. The calendering process and the embossing process may be performed in this order in a machine.

The depth D of the concave and convex portions can be controlled by appropriately adjusting the nip width of the rubber roll (see FIG. 3) facing the embossing roll 151. The nip width varies depending on the characteristics of the roll, but is preferably 20 to 50 mm, more preferably 25 to 45 mm, and further preferably 30 to 40 mm. When the nip width exceeds 50 mm, embossing becomes too strong and the difference between the front and back becomes large, or the paper thickness becomes high and the winding diameter DR of the roll becomes large. On the other hand, when the nip width is less than 20 mm, embossing may be weakened and the softness of the sheet may be poor. The nip width can be measured using carbon paper. As a measuring method, first, the nip of the embossing roll is released, and the carbon paper and the general copy paper are stacked and set. Next, a nip is applied to the embossing roll. Then release the nip and remove the carbon paper and copy paper. Since the color of the carbon paper at the part where the nip was applied by the embossing roll is transferred to the copy paper, the nip width can be measured.
Note that the depth D of the concave and convex portions of the concavities and convexities can be adjusted by narrowing the nip width when the irregularities of the embossing roll are deep, and widening the nip width when the irregularities of the embossing roll are shallow.

At the same time, printing, embossing, perforation processing, tail sealing, and cutting with a predetermined width (114 mm, etc.) can be performed with a roll winding machine, and the toilet roll 10 can be manufactured. Further, thereafter, film packaging processing can be performed to manufacture a toilet roll package.

The toilet paper may consist of 100% by weight of wood pulp, and may include waste paper pulp, non-wood pulp, and deinked pulp. In order to obtain the target quality, the content of NBKP (bleached softwood kraft pulp) is preferably 0 to 30% by mass, more preferably 0 to 20% by mass, and further preferably 0 to 10% by mass. The content of LBKP (hardwood bleached kraft pulp) is preferably 30 to 90% by mass, more preferably 40 to 80% by mass, and further preferably 50 to 70% by mass.
Moreover, the content rate of the waste paper pulp derived from a milk carton (milk pack) is preferably 0 to 60% by mass, more preferably 10 to 50% by mass, and further preferably 20 to 45% by mass. %, preferably 40 to 100% by mass, more preferably 50 to 90% by mass, and further preferably 55 to 80% by mass.
Waste paper pulp derived from milk carton (milk pack) is mainly composed of softwood pulp, which has the advantage of easily securing the strength of toilet paper, but on the other hand, there are large variations in quality, and if the content ratio is too high, the quality of the product will be affected. It is preferable that the content is within the above range.
Pulp manufactured from Eucalyptus genus Eucalyptus represented by Eucalyptus grandis and Eucalyptus globulus is preferable as the LBKP material.

In addition, 25 parts by mass or less of deinked pulp derived from newspapers, magazines, etc. can be added to 100 parts by mass of waste paper pulp derived from NBKP, LBKP and milk carton. The content of the deinking pulp in the toilet paper (sheet) when 25 parts by mass of the deinking pulp is mixed is 25 parts by mass/(100 parts by mass+25 parts by mass)×100=20% by mass. The content of deinked pulp is 0 to 20% by mass, preferably 0 to 10% by mass, more preferably 0 to 5% by mass or less, and most preferably 0% by mass. Since the deinked pulp is also used paper, the quality varies greatly. Deinked pulp usually contains a fluorescent dye, and if the content exceeds 20% by mass, a large amount of the fluorescent dye will be contained, which is not preferable.

When the deinked pulp contains a fluorescent dye, the difference Δ between the whiteness value of the toilet paper (sheet) under the UV-in condition and the whiteness value thereof under the UV-cut condition becomes large. Here, UV-in is a whiteness degree according to ISO 2470 when a C light source (including ultraviolet light) defined by CIE (International Commission on Illumination) is applied to the sheet surface side. UV-cut is a whiteness degree according to ISO 2470 when a C light source is irradiated on the sheet surface side through a filter that cuts off ultraviolet light having a wavelength of 420 nm or less. The difference Δ=(whiteness UV-in)−(whiteness UV-cut).
The difference Δ is preferably 0.0 to 2.5 points, more preferably 0.0 to 1.5 points, even more preferably 0.0 to 1.0 points, and most preferably 0.0 to 0.5 points. Is. The whiteness can be measured according to ISO 2470 using a high-speed spectrophotometer CMS-35SPX manufactured by Murakami Color Research Laboratory Co., Ltd.

In order to ensure proper strength in the toilet paper, it is possible to mix the raw materials by an ordinary means and adjust the strength by beating the pulp fiber. The beating to obtain the target quality is 0 to 200 ml, more preferably 0 to 150 ml, still more preferably 10 to 100 ml of commercially available virgin pulp with Canadian standard freeness measured according to JIS-P8121. Reduce water level.

In the case of using a virgin raw material for the stock, the toilet paper can be prepared by blending a softwood kraft pulp and a hardwood kraft pulp having a fiber length and a fiber roughness within a certain range in a specific range. As an additive to paper materials, depending on the quality required for the final product, softeners including debonder softeners, bulking agents, dyes, dispersants, dry paper strength enhancers, drainage improvers, pitch control agents, absorbency Improvers and the like can be used. It is also preferable not to use a wet strength agent.
When using a waste paper material as toilet paper, the same treatment as in the case of the virgin type is performed.
Details of the method for manufacturing toilet paper will be described later.

The toilet paper can be manufactured, for example, in the following order of (1) papermaking and creping, (2) calendar treatment, (3) embossing treatment, and roll winding processing as follows. Of these, (3) has already been described and will not be described.

(1) Papermaking and creping,
First, a web is made from the above stock on the wire part of a known paper machine and moved to the felt of the press part. Examples of the wire part method include a round net type, a long net (Ford linear) type, a suction breast type, a short net type, a twin wire type, and a crescent former type.
Then, the web is mechanically compressed by a suction pressure roll or a pressure roll or a press roll without suction, or dehydration is continued by a dehydration method such as ventilation drying with hot air. Suction pressure rolls or pressure rolls without suction are also used as a means to move the web from the press part to the Yankee dryer.

The web transferred to the Yankee dryer is dried by a Yankee dryer and a Yankee dryer hood, then creped by a creping doctor, and wound on a reel part.
Creping (making wavy wrinkles called crepes) is the mechanical compression of paper in the machine direction (the direction of sheet travel on a paper machine). When the toilet paper web is manufactured, the web on the Yankee dryer is peeled off by the creping doctor and wound up on the reel part, but the speed difference between the Yankee dryer and the reel part (speed of the reel part ≤ speed of the Yankee dryer ) Forms a crepe (wrinkle) with a creping doctor.
The quality required for toilet paper, that is, bulkiness, softness, water absorption, surface smoothness, aesthetics (crepe shape), etc. is affected by the speed difference. Although it depends on the conditions such as the speed difference, the basis weight of the web on the reel after creping is about 16 to 24 g/m ² , which is heavier than the basis weight of the web on the Yankee dryer before creping. The basis weight is preferably 18 to 23 g/m ² , and more preferably 19 to 22 g/m ² . If it exceeds the above range, the strength may be high and the paper may be stiff, and if it is less than the above range, the strength may be weak and the paper may be easily torn.

Here, the crepe rate based on the speed difference between the Yankee dryer and the reel is defined by the following equation.
Crepe rate (%) = 100 x (Yankee dryer speed (m/min)-reel speed (m/min)) / reel speed (m/min)
The quality and operability are largely determined by the creping conditions, and the operating conditions that optimize the creping conditions are important matters for those skilled in the art. In the present invention, the crepe ratio at the time of producing toilet paper is preferably 10 to 50%, more preferably 15 to 40%, most preferably 20 to 35%.

(2) Calendar Process FIG. 7 shows an example of the machine winder 100. As described above, the reel 112 wound by the reel part after the crepe is set in the machine winder 100, and calendered by the calendar machine 101 of the first stack. However, if necessary, a two-stage calendar process may be performed in the order of the first stack calender machine 101 and the second stack calender machine 102. It is also possible to carry out calendar processing with an on-machine calendar.
The paper thickness of the toilet paper before embossing (after calendaring) is preferably 0.5 to 1.5 mm/10 sheets, more preferably 0.6 to 1.3 mm/10 sheets, and further preferably 0.7 to 1. 1 mm/10 sheets. Further, the specific volume of the toilet paper in the raw fabric 114 before the embossing treatment (after the calendar treatment) is preferably 3.2 to 6.3 cm ³ /g, more preferably 3.5 to 5.8 cm ³ /g, and further preferably. Is 3.8 to 5.3 cm ³ /g.

The paper thickness of the toilet paper before the embossing treatment is the paper thickness of the original fabric 114 after the calendering treatment in FIG. 7, and corresponds to the paper thickness t1 in FIG. However, as will be described later, the paper thickness is a value measured with a measuring load of 3.7 kPa, and thus does not accurately reflect the paper thickness t1 in FIG.
Further, the paper thickness of the toilet paper after embossing shown in Tables 1 and 2 corresponds to the paper thickness t2 of FIG. 2, but since it is the value measured under the measuring load of 3.7 kPa, the paper thickness t2 is accurately reflected. Not what I did.
On the other hand, the depth (emboss depth) D of the concave and convex portions is measured in a state where the emboss is not compressed. Therefore, the depth D of the concave and convex portions is significantly larger than the value calculated from the paper thicknesses t1 and t2 (this value is the value obtained by compressing the emboss with the measurement load of 3.7 kPa).

Each of the calenders 101 and 102 preferably comprises two metal rolls, but one of the two rolls may be an elastic roll so that soft calendering can be performed.
The linear pressure of the calender is preferably 2.5 to 7.5 kgf/cm, more preferably 3.0 to 7.0 kgf/cm. When the linear pressure exceeds the above range, the bulk becomes small and the softness may be poor. Further, if the wire thickness is less than the above range, the bulk becomes large and the winding diameter DR of the roll becomes large. Further, it is preferable that the linear pressure of the second stack is higher than that of the first stack.
During the calendar process, the draw can be adjusted appropriately. The draw between the reel 112 before the ply-up and the raw fabric 114 after the calendar process is preferably 100 to 110%.

The calendered raw fabric 114 is embossed by, for example, the roll winding machine 150 shown in FIG. 3 to obtain the toilet roll 10. Note that the winding hardness (and winding density) is determined by pressing the raw roll 10W from the outer peripheral side when winding the wide toilet paper raw roll 10W by the winding mechanism 153 in the roll winder 150 of FIG. The pressing force of the rider roll 154 for sequentially winding the seat can be adjusted by setting it within a predetermined range.

It is needless to say that the present invention is not limited to the above-described embodiments and covers various modifications and equivalents included in the concept and scope of the present invention.

The content of pulp composition is (% by mass) NBKP 5%, LBKP 60%, milk carton-derived waste paper pulp 35%, deinking pulp is not contained, and the apparatus shown in FIGS. The toilet paper and toilet roll shown in Table 3 were manufactured.

The following evaluation was performed.
The maximum load until breaking was measured for each toilet paper (one sheet) based on the tensile strength in dry direction DMDT and the tensile strength in dry direction DCDT: JIS P8113. Specific test pieces and measurement methods are as described above.
Basis weight: Measured according to JIS P8124 and defined as per sheet.
Paper thickness: Measured using a thickness gauge (dial thickness gauge "PEACOCK" manufactured by Ozaki Seisakusho). The measurement conditions were a measurement load of 3.7 kPa, a probe diameter of 30 mm, a sample was placed between the probe and the measuring table, and the gauge was read when the probe was lowered at a speed of 1 mm or less per second. For the web and roll before and after the calender treatment, 10 sheets were stacked and measured. The measurement was repeated 10 times and the measurement results were averaged. Then, the obtained average value per sheet was divided by the number of sheets to obtain the sheet thickness per sheet.

Specific volume: The thickness per sheet was divided by the basis weight per sheet, and expressed in volume cm ³ per unit g.
Mass of roll not containing core and mass of core: Measured using an electronic balance. For the measurement, 10 rolls were measured and the measurement results were averaged.
Roll diameter DR, core outer diameter DI: Measured using a diameter rule manufactured by Muratec KDS Co., Ltd. For the measurement, 10 rolls were measured and the measurement results were averaged.
The winding density of the roll, the embossing depth D, and the hardness of the core were measured by the methods described above. The winding density of the roll was obtained by measuring 10 rolls used for measuring the winding diameter DR of the roll and averaging the measurement results.
Roll length: About the sheet between the perforations, the length of 10 sheets was measured. Then, the number of sheets on the roll was measured. It was determined by proportional calculation from the length of 10 sheets and the number of sheets. For example, when the length of 10 sheets is 2.275 m and the number of sheets is 665 sheets, 2.275 m×(665/10)=151 m.

Sensory evaluation was performed by 20 monitors. The evaluation standard was 5 points. It is good if the evaluation standard is 3 points or more.
Note that basis weight, tensile strength, thickness (paper thickness), mass of roll and mass of core, specific volume, winding diameter DR, core outer diameter DI, hardness of core, winding density, winding length, embossing depth. The measurement was carried out after maintaining the equilibrium state under the temperature and humidity conditions (23±1° C., 50±2% RH) specified in JIS-P8111.

The obtained results are shown in Tables 1 to 3.

As is clear from Table 1 to Table 3, the roll length of the toilet roll, the roll diameter, the roll mass not including the core, the mass of the core, the roll density of the roll, and the outer diameter of the core of each Example In this case, the touch was good, the winding length per roll was long, and the core could be made difficult to crush without impairing cost and productivity.
Furthermore, in the case of each example in which the strength (DMDT) of the sheet was 2.5 to 7.0 N/25 mm, the sheet strength (DMDT) was less than 2.5 N/25 mm in comparison with Example 22 in which the sheet was torn. The hardness was excellent. However, Example 22 also has no practical problem.
In addition, in the case of each example in which the sheet strength (DMDT) was 2.5 to 7.0 N/25 mm, the sheet softness was higher than that of Example 23 in which the sheet strength (DMDT) exceeded 7.0 N/25 mm. Was excellent. However, Example 23 also has no practical problem.

On the other hand, in the case of Comparative Example 1 in which the roll length was less than 105 m, the roll diameter was less than 100 mm, and the roll mass was less than 225 g, the roll replacement frequency was high.
In the case of Comparative Example 2 in which the winding length exceeded 210 m, the winding diameter exceeded 140 mm, and the roll mass exceeded 485 g, the roll diameter increased and it was difficult to fit in the toilet paper holder.

In Comparative Examples 6 and 9 in which the outer diameter of the core exceeded 48 mm, the core was easily crushed. However, in the case of Comparative Example 6, the apparent basis weight of the core was large and the strength was high, and the core was harder to be crushed than in Comparative Example 9.

In the case of Comparative Example 4 in which the hardness of the core was less than 0.7 mm, the productivity of the core was poor.
In the case of Comparative Example 3 in which the hardness of the core exceeded 3.6 mm, the core was crushed when the toilet roll was manufactured.
In the case of Comparative Example 4, the ratio was less than 2.0 mm/(g/cm ³ ), the apparent basis weight of the core exceeded 450 g/m ² , and the cost of the core increased.

In the case of Comparative Example 5 in which the outer diameter of the core was less than 25 mm, it became difficult to mount the roll on the toilet holder.

In Comparative Example 7 manufactured under the same manufacturing conditions as in Example 18 except that no embossing was provided, the sheet was harder than Example 18 and inferior in softness because there was no embossing. Moreover, the winding density exceeded 0.35 g/cm ³ , and the core was crushed.

In the case of Comparative Example 8 in which the emboss depth exceeded 0.40 mm, the volume became too bulky, the winding diameter exceeded 140 mm, the roll diameter became large, and it was difficult to fit in the toilet paper holder. In Comparative Example 8, the winding density was less than 0.17 g/cm ³ .

In Comparative Examples 3 and 6, the ratio exceeded 11.5 mm/(g/cm ³ ), and the core was easily crushed.

When the commercially available products 1 to 3 were evaluated in the same manner, the commercially available products 1 and 2 had a winding length of less than 105 m, and the frequency of roll replacement was high.
Since the commercial product 3 had no core and no embossing, it was inferior in softness.

2 embossing
10 Toilet Roll 10x Toilet Paper D Embossing Depth (Concave Depth)

The present invention relates to a method for manufacturing a toilet roll in which 1-ply toilet paper is wound.

Therefore, it is an object of the present invention to provide a method for manufacturing a long toilet roll which has a good feel and which is difficult to crush the core without impairing cost and productivity.

In order to solve the above problems, the method for manufacturing a toilet roll of the present invention is a toilet roll in which a roll of one-ply toilet paper having a plurality of irregularities in which one surface is a convex portion and the corresponding opposite surface is a concave portion. A roll having a roll length of 105 to 210 m, a roll diameter of 100 to 140 mm, a roll mass not including a core per roll width of 114 mm of 225 to 485 g, and a mass of the core per roll width of 114 mm of from 3.2 to 6 .0G, an outer diameter of said core 25～48Mm, winding density of the roll Ri 0.17~0.35g / cm ³ der placed the core laterally on a rigid base so that the axis is horizontal, A compressor (area 2.0 cm ² ) is pressed into the center of the outer surface of the core from above under the condition of a speed of 10 mm/min, and the pressing depth when the pressure pressed by the compressor is 0.5 gf/cm ² is T0. When the pressure is 250 gf/cm ² and the indentation depth is Tm and (Tm-T0) is the hardness of the core, the hardness of the core is 0.7 to 3.6 mm, and the axial length is Is wound around the paper tube that becomes the core after cutting longer than the product width, and a log whose width is longer than the product width at the length of the product is cut into a circular slice at the product width in the axial direction with a log saw, We manufacture a plurality of the toilet rolls.

The depth of the concave and convex portions is preferably 0.01 to 0.40 mm .
The apparent basis weight of the core is preferably 250 to 450 g/m ² .
The ratio represented by (hardness of the core)/(winding density of the roll) is preferably 2.0 to 11.5 mm/(g/cm ³ ).
It is preferable that the tensile strength DMDT in the longitudinal direction of the toilet paper when dried according to JIS P8113 is 2.5 to 7.0 N/25 mm.
It is preferable that the tensile strength DCDT of the above-mentioned toilet paper in the dry direction based on JIS P8113 is 0.7 to 2.2 N/25 mm.
The unevenness is preferably embossed.

Claims (8)

A toilet roll obtained by winding a 1-ply toilet paper roll having a plurality of irregularities in which one surface is a convex portion and the corresponding opposite surface is a concave portion,
Roll length is 105 to 210 m, roll diameter is 100 to 140 mm, core mass per roll width 114 mm is 225 to 485 g, mass of the core per roll width 114 mm is 3.2 to 6.0 g, and the core is Has an outer diameter of 25 to 48 mm,
A toilet roll having a roll density of 0.17 to 0.35 g/cm ³ . The toilet roll according to claim 1, wherein the depth of the concave and convex portions is 0.01 to 0.40 mm. The toilet roll according to claim 1 or 2, wherein the core has a hardness of 0.7 to 3.6 mm. The toilet roll according to claim 1, wherein an apparent basis weight of the core is 250 to 450 g/m ² . The ratio represented by (hardness of the core)/(winding density of the roll) is 2.0 to 11.5 mm/(g/cm ³ ), wherein Toilet roll. The toilet roll according to any one of claims 1 to 5, wherein a longitudinal tensile strength DMDT of the toilet paper in a dry direction based on JIS P8113 is 2.5 to 7.0 N/25 mm. The toilet roll according to any one of claims 1 to 6, wherein a transverse tensile strength DCDT of the toilet paper when dried according to JIS P8113 is 0.7 to 2.2 N/25 mm. The toilet roll according to any one of claims 1 to 7, wherein the unevenness is embossed.