JP2017205179A - Toilet roll - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a toilet roll that excels in softness of the sheet without lowering a basis weight as well as making a wound length per roll longer, that facilitates cutting at perforation from the beginning to the end of a roll, and that saves space in carrying and storage.SOLUTION: In the toilet roll 10, there is a plurality of irregularities 2 in which one face is projecting while the other corresponding opposite face is recessing. Two-ply toilet paper 10x having perforations 10m along the width direction is wound in a roll; in which the wound length is 63-105 m, the wound diameter is 100-140 mm, the roll weight including a core per roll width 114 mm is 200-400 g, and the longitudinal tensile strengh DMDT in dryness of the two ply based on JIS P8113 of the perforation per roll width 114 mm is 3.6-14.8 N/114 mm.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a toilet roll obtained by winding up two-ply toilet paper.

Toilet papers that are packaged mainly in units of 4 rolls or 12 rolls are commercially available. 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. Storage space is also limited in homes, workplaces, and public facilities.
For this reason, toilet rolls have been developed in which the basis weight per sheet of toilet paper is reduced to 14 g / m ² or less and the winding length is increased (long) (Patent Documents 1 and 2). .
In addition, the applicant of the present application has developed a toilet roll having a longer winding length while improving the feeling of use by increasing the basis weight per sheet of toilet paper to be higher than 13 g / m ² (Patent Documents 3 and 4). ).

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

By the way, generally, a toilet roll has a plurality of perforations along the width direction, and is used by being cut into a sheet shape at the perforations. However, since the long toilet roll is heavy, it is difficult to rotate with the weight of the toilet roll when starting to use, and if the perforation strength is weak, the perforation in the middle before cutting into the required length sheet There is a problem of being cut.
On the other hand, if the perforation is not provided or the strength of the perforation is increased, it is easy to cut the sheet at a desired length at the beginning of use, but it becomes difficult to cut the sheet when the roll becomes lighter toward the end of use. Even when the strength of the sheet is increased, the perforation strength is increased, so that there is a similar tendency and the softness of the sheet is inferior.

On the other hand, when the basis weight of the paper is lowered to obtain a long toilet roll, the strength is lowered and the feeling of use and bulkiness are lowered. Therefore, it is considered that the softness can be improved by embossing the sheet so as to have an appropriate uneven shape.
However, it has been found that when embossing is applied to a sheet of a long toilet roll, the strength of the perforation is weakened, and it is difficult to secure a strength that is easy to cut from the beginning to the end of use of the roll. This is thought to be due to the tendency of the interfiber bond to loosen or break when embossing is inserted, and thus the strength of the jumper portion that affects the strength of the perforation. In general, the paper breaks starting from the weakest part, so it is assumed that the paper breaks from the embossed part.

  Therefore, the present invention is excellent in sheet softness without lowering the basis weight, lengthens the winding length per roll, and the perforation is easy to cut from the beginning to the end of use of the roll, saving space during carrying and storage. The purpose is to provide an excellent toilet roll.

  In order to achieve both the softness of the toilet paper sheet and the ease of cutting, the present inventors have provided unevenness by embossing and the like, and the depth of the unevenness of the unevenness so that the strength of the perforation is not reduced by the unevenness. The perforation strength that makes it easy to cut from the beginning to the end of use of the roll was found.

  In order to solve the above-described problem, the toilet roll of the present invention has a two-ply toilet paper having a plurality of projections and recesses on one side and having a perforation along the width direction. A roll length of 63 to 105 m, a roll diameter of 100 to 140 mm, a roll mass including a core per roll width of 114 mm is 200 to 400 g, and the perforation per roll width of 114 mm. The tensile strength DMDT in the machine direction when drying two plies according to JIS P8113 is 3.6 to 14.8 N / 114 mm.

It is preferable that the depth of the concave and convex portions is 0.03 to 0.45 mm.
The ratio represented by (DMDT of the perforation) × 1000 / (the roll mass) is preferably 13 to 53 N / (114 mm × g).
The 2-ply DMDT of the toilet paper not including the perforation is preferably 11 to 30 N / 114 mm.
It is preferable that the bond rate represented by {the length of the splinter part / (the length of the splinter part + the length of the cut line)} × 100 of the perforation is 20 to 80%.
It is preferable that the length of the perforated part of the perforation is 0.3 to 2.7 mm.
It is preferable that the perforation line has a length of 0.4 to 3.3 mm.
It is preferable that the unevenness is embossed.

  According to the present invention, the sheet is excellent in softness without reducing the basis weight, and the winding length per roll is increased, and the perforation is easily cut from the beginning to the end of use of the roll, saving space for carrying and storing. A toilet roll excellent in properties can be obtained.

It is a perspective view which shows the external appearance of the toilet roll which concerns on embodiment of this invention. It is sectional drawing which shows the embossing provided in the roll 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 emboss depth. It is another figure which shows the measuring method of emboss 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 method of measuring the intensity | strength of a perforation. It is a figure which shows the measuring method of emboss depth in case emboss is connected with the flow direction (MD direction).

Preferred embodiments of the present invention will be described below, but these are given for illustrative purposes 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 two-ply toilet paper 10x having a plurality of irregularities and having a perforation 10m is wound into a roll shape. The length (winding length) is 63 to 105 m, the winding diameter DR is 100 to 140 mm, the roll mass described later is 200 to 400 g, and the two-ply tensile strength DMDT described below is 3.6 to 14.8 N / 114 mm.
In addition, let the surface of the roll outer side of the toilet paper 10x be the roll surface (or the surface of the toilet paper) 10a, and let the surface inside the roll be the roll back surface (or the back surface of the toilet paper) 10b.

When the roll length of the toilet roll 10 is less than 63 m, the roll length per roll is shortened and space saving during storage cannot be achieved. When the roll length of the roll exceeds 105 m, the roll diameter DR becomes too large and it is difficult to fit in a toilet paper holder or the like.
The winding length is preferably 68 to 95 mm, more preferably 73 to 85 mm.

When the winding diameter DR is less than 100 mm, the winding length is also shortened to less than 63 m. When the winding diameter DR exceeds 140 mm, it becomes difficult to fit in a toilet paper holder or the like.
The winding diameter DR is preferably 110 to 135 mm, more preferably 115 to 123 mm.

The roll mass including the core (core) with a roll width W of 114 mm is 200 to 400 g. Here, when the roll width W is different from 114 mm, the roll mass is obtained by converting W into 114 mm. 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 W of 114 mm.
When the roll mass is less than 200 g, the winding length per roll is shortened and space saving during storage cannot be achieved. When the roll mass exceeds 400 g, the winding diameter DR becomes too large and it is difficult to fit in the toilet paper holder or the like.
The roll mass is preferably 230 to 360 g, more preferably 250 to 330 g.

DMDT (Dry Machine Direction Tensile strength) in the dry direction based on JIS P8113 having a two-ply perforation of 10 m per 114 mm in roll width W is 3.6 to 14.8 N / 114 mm. .
As shown in FIG. 8, the DMDT has a strip shape in which the MD direction (longitudinal direction perpendicular to the width W) of the two-ply sheet (toilet paper) 10x is the longitudinal direction of length L1 = 250 mm, and the width W is itself The test piece S1 to be the width direction is cut out and measured. If the distance between the gripping tool and the gripping tool of the tensile tester is 100 mm and this distance can be secured to 100 mm, there is no effect even if the length of the test piece is shorter than L1 = 250 mm. One perforation 10m is made to enter approximately the center in the longitudinal direction of the test piece S1. Then, the measurement is performed by pulling in the MD direction at a tension speed of 300 mm / min before and after the perforation 10 m so as to divide one perforation 10 m.

In addition, when the width Y of the gripping tool is smaller than 114 mm, the sheet is folded along the MD direction so as to have a width Z (the width Z may be equal to or smaller than the width Y), pulled at the width Z, and the DMDT at that time is It may be adopted as it is. For example, when the sheet width is 114 mm, if the sheet is folded in half so that the half width Z = 57 mm, the width is ½ and the thickness (number of sheets) is doubled. This is because it becomes the same as in the case of a width of 114 mm.
In general, DMDT is measured with a width of 25 mm. In this case, since the measured value varies depending on the number and length of the perforated part of the perforation and the cut line, the measurement is performed with a width close to the roll width W. Thus, it is preferable to measure by folding a sheet having a roll width W to a width of 25 mm.
When the roll width W is different from 114 mm, DMDT is obtained by converting W into 114 mm. For example, when the roll width W is 105 mm, the mass obtained by multiplying the DMDT by a coefficient (114/105) is DMDT per 114 mm.
If the perforated DMDT is less than 3.6 N / 114 mm, especially when the toilet roll is difficult to rotate due to its weight at the beginning of use, the perforation becomes weak and before the sheet is cut into a required length. Cut at perforations on the way. When the perforated DMDT exceeds 14.8 N / 114 mm, the strength of the perforated line is too high, and if the roll becomes lighter as the use proceeds, it becomes difficult to cut the sheet.
The perforated DMDT is preferably 5.2 to 12.3 N / 114 mm, more preferably 6.7 to 9.8 N / 114 mm.

<Unevenness>
The toilet roll 10 (toilet paper 10x) of the present invention has a plurality of irregularities. This unevenness can be applied by embossing, for example. In the present invention, since the sheet is 2 ply, it becomes single emboss or double emboss, but single emboss is preferable. Of course, a known double-height embossing roll can be used, or single embossing can be performed multiple times.
In the double embossing, embossing is performed on each two-ply sheet, and the embossed convex surfaces of each sheet are laminated so as to face each other. By using double embossing, it is easy to increase the paper thickness and specific volume, and to increase water absorption. Moreover, when making double embossing, it can be made into 2 plies by edge embossing or glue, but using glue is preferable because the shape of the emboss can be easily maintained. Further, as the double embossing, a nested embossing is preferable.
On the other hand, single embossing makes it easier to lower the specific volume than double embossing, and is suitable for long toilet rolls.
Further, the emboss pattern (emboss size, depth, number, area ratio) can be changed as appropriate.
Hereinafter, embossing will be described as an example of unevenness.
As shown in FIG. 3, the single embossing is formed by pressing the embossing convex portion of the embossing roll 151 only from one surface of the toilet paper 10 x.
FIG. 2 is a cross-sectional view showing the single emboss 2 provided on the toilet roll 10 (toilet paper 10x).
In the example of FIG. 2, the toilet paper 10x includes two plies, and the upper part of FIG. 2 corresponds to the roll surface 10a side. The embossing (single embossing) 2 in which the concave portion 2R appears on the surface of the toilet paper 10x against which the embossing roll 151 is pressed (the surface in FIG. 2) and the convex portion 2P appears on the back surface is formed.
2A shows a case where the emboss depth is deep, and FIG. 2B shows a case where the emboss depth is shallow.

In this case, the paper thickness t2 of the toilet paper 10x after the embossing process (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 on the back surface) is the same. However, the sheet shown in FIG. 2A, in which the embossed depth (corresponding to the depth of the concave and convex portions) D is deepened from the sheet obtained by thinning the base paper to the paper thickness t1 by calendar processing, is increased. Is soft and excellent in texture. This is considered to be because the embossed unevenness in FIG. 2A is higher in bulk with respect to the paper thickness of the base paper (lower in density), easily deforms, and improves the softness of the sheet. .
Further, in the case of FIG. 2A, in order to increase the embossing depth D, the paper thickness t1 per sheet needs to be reduced by that amount to make the unevenness conspicuous. The softness of the sheet is improved due to the strong performance of the sheet.
Of course, the embossing process may be performed without performing the calendar process. In this case, the sheet thickness of the sheet before the embossing process can be controlled by pulp blending, beating conditions, crepe rate, etc. so as to ensure the embossing depth.

  On the other hand, if the surface of the toilet paper 10x is made smooth without providing an emboss, the surface is too smooth and the surface feels crisp and the sheet is inferior in softness. In addition, when the recessed portion 2R of the emboss is provided on the outer side of the roll (the roll surface 10a side) where water easily adheres to the toilet paper 10x when using the warm water washing toilet seat, etc. The softness of the sheet is improved.

  The means for ensuring the softness of the toilet paper (sheet) 10x is not limited to embossing, as long as it provides unevenness on the surface. Good. In this case, the depth of the concave and convex portions is preferably in a range corresponding to the emboss depth D.

Further, the depth D of the concave and convex portions is obtained by measurement using a microscope.
As the microscope, a product name “One-shot 3D measurement macroscope VR-3100” manufactured by KEYENCE can be used. As the microscope image observation / measurement / image analysis software, the product name “VR-H1A” can be used. Measurement is performed under the conditions of a magnification of 12 and a visual field area of 24 mm × 18 mm. Note that the measurement magnification and the visual field area may be appropriately changed according to the required embossing size.

  First, as shown in FIG. 4, the longest part a of the peripheral edge fr of the emboss is obtained. Fig.5 (a) shows the height profile on XY plane by a microscope, and it turns out that the height of the toilet paper surface is represented by the shading. The dark colored portions in FIG. 5A indicate individual embosses 2, and the longest portion a of one emboss 2 can be distinguished from FIG. 5A. When a line segment A-B crossing the longest portion a is drawn, a height (measured cross section curve) profile of the emboss 2 is obtained as shown in FIG. Here, since the embossed convex portion (non-embossed portion) and the concave portion can be recognized by the color density of the XY plane image, the line segment AB can be determined so as to cross the portion where the convex portion and the concave portion are adjacent to each other. That's fine.

Here, the height profile in FIG. 5 (b) is a (measurement) cross-sectional curve S representing the unevenness of the actual toilet paper sample surface, but noise (fiber lumps on the surface of the toilet paper or fibers are present). In addition, it includes a steep peak due to a beard-like shape or a portion having no fiber), 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 of the contour curve W, and the inflection The minimum value sandwiched between the points P1 and P2 is obtained and set as the minimum value Min of the depth. Further, the average value of the depth values of the inflection points P1 and P2 is set as the maximum value Max.

  In this way, the depth D of the concave and convex portions is set to D = maximum value Max−minimum value Min. The distance (length) on the XY plane between the inflection points P1 and P2 is defined as the length of the longest portion a. Note that the “contour curve” is λc: 800 μm from the cross-sectional curve (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”). It is a curve obtained by removing the surface roughness component with 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, λc is set to 250 μm, for example. The P1 interval between adjacent embosses is the interval between two P1s when P1 and P2 are similarly obtained for the next emboss connected to the left or right in FIG. 6 and aligned with P1, P2, and P1 between adjacent embosses. is there.

Similarly, in FIG. 5A, the depth D of the concave / convex concave portion is also measured for the longest portion b in the direction perpendicular to the longest portion a, and the depth D of the concave / convex concave portions of the longest portions a and b is measured. Of these, the larger value is adopted as the depth D of the concave and convex portions. The above measurement is performed on any ten embosses 2 on the surface 10a of the toilet paper 10x, and the average value is adopted as the final depth D of the concave and convex portions.
However, as shown in FIG. 9, when the emboss 2 is connected in the flow direction (MD direction), the longest part a becomes the same as the winding length, the height difference cannot be obtained, and the depth D of the concave portion is set. It cannot be measured. Therefore, the depth D of the recess can be measured by drawing a line segment AB so as to straddle the emboss 2 in the width W direction orthogonal to the direction (MD direction) where the emboss 2 is connected.
Similarly, when the emboss 2 is connected in the width W direction (CD direction), a line segment AB is drawn across the emboss 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 the surface 10a side.
Moreover, when calculating | requiring the depth D of an uneven | corrugated recessed part, when selecting arbitrary 10 embossing (unevenness | corrugation) 2, from the edge part (position which starts using toilet paper) of the toilet roll 10, In the portion corresponding to 10% of the roll length of the toilet roll 10 (for example, when the roll length is 75 m, the portion of 75 m × 10% = 7.5 m from the end portion), any of the embosses 2 arranged along the width direction Choose 10 pieces. In addition, 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. In addition, when the emboss 2 to be measured hits the perforation, the measurement is performed on the group of the embosses 2 on the outer winding side adjacent to the perforation.

The depth D of the concave and convex portions is preferably 0.03 to 0.45 mm, more preferably 0.05 to 0.40 mm, and still more preferably 0.07 to 0.35 mm.
When the depth D is smaller than the above range, the degree of unevenness becomes small, the bulk becomes low (the density becomes 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 remarkable and the bulk becomes too high (the density becomes too low), the winding diameter DR becomes too large, and it becomes difficult to attach the toilet roll 10 to the paper holder. There is. In addition, the strength of the perforation may become too low, and the perforation may be cut off before being cut into a sheet having a required length.

The two-ply tensile strength DMDT of the toilet paper in the machine direction (MD) when dried based on JIS P8113 without perforation is preferably 11-30 N / 114 mm, more preferably 13-25 N / 114 mm, more preferably 16 21 N / 114 mm.
As shown in FIG. 8, the test piece S3 having the same dimensions as the test piece S1 is cut out at a portion where the perforation 10m of the sheet (toilet paper) 10x does not enter, and measurement is performed by pulling in the MD direction. By setting the DMDT of toilet paper that does not include perforations within the above range, the DMDT of the perforations can also be within a predetermined range.
When the roll width W is different from 114 mm, DMDT is obtained by converting W into 114 mm. For example, when the roll width W is 105 mm, the mass obtained by multiplying the DMDT by a coefficient (114/105) is DMDT per 114 mm.

  In addition, all DMDT and DCDT prescribed | regulated by this invention are measured on the conditions of the tension | pulling speed of 300 mm / min, with the space | interval of the gripping tool of a tension tester as 100 mm.

The ratio represented by (DMDT of the perforation) × 1000 / (the mass of the roll) is preferably 13 to 53 N / (114 mm × g), more preferably 20 to 47 N / (114 mm × g), and still more preferably. Is 24-38 N / (114 mm × g).
Even if the value of DMDT on the sewing machine surface is the same, if the roll mass is heavy, it becomes easy to cut off at the beginning of use, so the above ratio expressed by DMDT of the sewing machine surface per roll mass was specified.
When the ratio is less than 13 N / (114 mm × g), the perforation strength is weakened, and the cut may be cut in the middle before being cut into a sheet having a required length. If the ratio exceeds 53 N / (114 mm × g), the perforation strength may be too high to make it difficult to cut the sheet.

As shown in FIG. 1, a portion of the perforation 10 m where the sheets are connected in the MD direction is a jumping portion 10 m 1. Moreover, the site | part which is located between the jumper parts 10m1 adjacent to the width W direction and becomes a cut | interruption in MD direction is the cut line 10m2. Moreover, the length of the joint part 10m1 and the cut line 10m2 is defined along the width W direction.
Here, the bond rate represented by {the length of the jumper portion 10m1 / (the length of the jumper portion 10m1 + the length of the cut line 10m2)} × 100) of the perforation 10m is preferably 20 to 80%. Yes, more preferably 25-65%, still more preferably 35-50%.
By managing the bond rate within the above range, the strength (DMDT) of the perforation 10 m can be reliably managed within the above range.
When the bond rate is less than 20%, the strength of the perforation 10m is weakened, and the cut may be cut at a middle perforation before cutting into a sheet having a required length. On the other hand, if the bond rate exceeds 80%, the strength of the perforation 10m becomes strong, and the strength of the perforation may be too high to make it difficult to cut the sheet.

Further, the length of the jumper portion 10m1 is preferably 0.3 to 2.7 mm, more preferably 0.5 to 2.2 mm, and still more preferably 0.8 to 1.7 mm.
The length of the cut line 10m2 is preferably 0.4 to 3.3 mm, more preferably 0.9 to 2.8 mm, and still more preferably 1.4 to 2.3 mm.
By managing the length of the jumper portion 10m1 and the cut line 10m2 within the above range, the bond rate and thus the strength (DMDT) of the perforation 10m can be reliably managed within the above range.

The tensile strength DCDT (Dry Cross Direction Tensile strength) of 2-ply lateral (CD) toilet paper during drying based on JIS P8113 which does not include perforations is preferably 0.7 to 2.2 N / 25 mm, more preferably Is 0.8 to 1.8 N / 25 mm, more preferably 1.0 to 1.5 N / 25 mm.
If DCDT is less than the above value, it may be easily shaken and not suitable for practical use. When DCDT is higher than the above value, it becomes hard and the softness of the sheet may be impaired.
The flow direction of toilet papermaking is defined as “longitudinal direction”, and the direction perpendicular to the flow direction is defined as “lateral direction”.

The roll winding density is preferably 1.0 to 2.1 m / cm ² , more preferably 1.2 to 1.9 m / cm ² , and still more preferably 1.4 to 1.7 m / cm ² .
If the roll is wound too tightly, excessive press may be applied to the inner roll toilet paper, and the embossing provided on the inner roll toilet paper may be crushed. On the other hand, if the roll is wound too weakly, the emboss will not be crushed, but the winding diameter will increase and it will be difficult to attach to the paper holder, or the inner winding will be too weak and the inner winding side of the roll will be axial May cause a defective product. For these reasons, the winding density was defined as a factor for expressing the winding strength of the roll.
The winding density is expressed by (winding length × number of plies) ÷ (cross-sectional area of roll). The cross-sectional area of the roll is represented by {the cross-sectional area of the outer diameter (rolling diameter DR) portion of the roll}-(the cross-sectional area of the core outer diameter portion). The core outer diameter DI (see FIG. 1) is the diameter of the center hole of the roll. When a core (core paper tube) is mounted inside the roll, the core outer diameter corresponds to DI.
When the winding density is less than 1.0 m / cm ² , the winding diameter DR exceeds 140 mm, and it becomes difficult to fit in a toilet paper holder or the like, and the winding force of the inner winding becomes too weak, and the inner winding side of the roll is It may jump out in the axial direction (poor shape retention of the roll is inferior), resulting in a defective product. When the winding density exceeds 2.1 m / cm ² , the softness of the sheet may be inferior, or the embossing provided on the toilet paper may be crushed, and the cosmetics may be deteriorated during use.

  The outer diameter of the core (winding core) is preferably 35 to 45 mm, more preferably 37 to 42 mm. In the case of a toilet roll without a core, the inner diameter of the toilet roll is regarded as the outer diameter of the core.

Toilet paper 10x is the basis weight of the sheet per sheet is preferably 13 g / ^{m 2,} greater 18 g / ^{m 2} or less, more preferably 13.5~17.0g / ^{m 2,} more preferably 14.1~16.0g / M ² .
The sheet thickness is preferably 0.50 to 1.20 mm / 10 sheets, more preferably 0.60 to 1.05 mm / 10 sheets, and still more preferably 0.70 to 0.90 mm / 10 sheets.
If the basis weight and paper thickness of the sheet are in the above ranges, it is preferable because the winding length and winding diameter DR can be easily adjusted to the above ranges. Moreover, the tactile sensation when using toilet paper is improved.
As a method of adjusting the sheet basis weight and paper thickness to the above ranges, the calender conditions (paper thickness and specific volume after calendering) and embossing conditions of the base paper web are defined.

When the basis weight per sheet of the toilet paper 10x is 13 g / m ² or less or the paper thickness is less than 0.50 mm / 10 sheets, the strength is lowered and the feeling of use (bulk) is also lowered. There is a case. When the basis weight per piece of toilet paper 10x exceeds 18 g / m ² or the paper thickness exceeds 1.20 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 3.0 to 7.0 cm ³ / g, more preferably 3.3 to 6.7 cm ³ / g, and still more preferably 3.6 to 6.4 cm ³ / g.
If the specific volume is less than 3.0 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, if the specific volume exceeds 7.0 cm ³ / g, the bulk (bulk height) of the sheet increases, but the paper thickness may increase and the winding diameter may increase.

FIG. 3 shows an example of a roll winding machine 150. The base paper roll is calendered to become a raw fabric 4 (sheet thickness t1 of the sheet). This raw fabric 4 is set on a roll winding machine 150 and subjected to a single embossing process by an embossing unit (embossing roll) 151, and then wound around a wide toilet paper roll 10W having the above winding diameter by a winding mechanism 153. Taken. Thereafter, the original roll 10W is cut into a predetermined width (114 mm or the like) to form the toilet roll 10.
The roll winding machine 150 can be roughly classified into two types: a surface method and a center method. The surface method is a method in which the roll to be wound is wound while being supported by a plurality of other drive rolls from the outside. The wound toilet roll 10 is easy to control the winding diameter, and the production speed becomes higher. The center method is a method of winding by driving a shaft passing through the center of the winding roll. The wound toilet roll 10 is a relatively soft product and is suitable for a product with delicate embossing. In the present invention, any method can be used for winding, but the surface method is preferred.
In addition, the machine winder 100 is incorporated into the roll winder 150, or both the calendars 101 and 102 (two stacks) or one (one stack) is incorporated into the roll winder 150, and the roll winder machine uses the calendar. Processing and embossing processing may be performed in this order.

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 roll characteristics, but is preferably 20 to 50 mm, more preferably 25 to 45 mm, and still more preferably 30 to 40 mm. When the nip width exceeds 50 mm, the embossing becomes too strong and the front / back difference increases, or the paper thickness increases and the roll diameter DR of the roll increases. On the other hand, when the nip width is less than 20 mm, the embossing becomes weak and the softness of the sheet may be inferior. The nip width can be measured using carbon paper. As a measuring method, first, the nip of the embossing roll is escaped, and carbon paper and general copy paper are stacked and set. Next, a nip is put on the embossing roll. Then, let the nip escape and remove the carbon paper and copy paper. Since the color of the carbon paper where the nip is 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 can be adjusted by narrowing the nip width if the unevenness of the embossing roll is deep, and increasing the nip width if the unevenness of the embossing roll is shallow.

  At the same time, the roll winder can perform printing, embossing, perforation, tail sealing, and cutting with a predetermined width (114 mm, etc.), and the toilet roll 10 can be manufactured. Furthermore, the package body of a toilet roll can be manufactured by film packaging processing after that.

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 (conifer bleached kraft pulp) is preferably 0 to 30% by mass, more preferably 0 to 20% by mass, and further preferably 5 to 15% 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 still more preferably 50 to 70% by mass.
Moreover, the content rate of the waste paper pulp derived from the milk carton (milk pack) is preferably 0 to 60% by mass, more preferably 10 to 50% by mass, and further preferably 20 to 40% by mass. Preferably, it is 40-100 mass%, More preferably, it is 50-90 mass%, More preferably, it is 60-80 mass%.
Waste paper pulp derived from milk cartons (milk cartons) is mainly softwood pulp and has the advantage of ensuring the strength of toilet paper. On the other hand, quality variation is large, and if the content is too high, the quality of the product will be affected. The content is preferably in the above range.
Pulp produced from Eucalyptus eucalyptus represented by Eucalyptus genus Grandis and Eucalyptus globulus is preferred as the grade of LBKP.

  Further, 25 parts by mass or less of deinked pulp derived from used newspaper or magazine waste paper can be blended with 100 parts by mass of waste paper pulp derived from NBKP, LBKP, or milk carton. In addition, when 25 mass parts of deinked pulp is blended, the content of deinked pulp in the toilet paper (sheet) is 25 mass parts / (100 mass parts + 25 mass parts) × 100 = 20 mass%. The content of the 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 deinked pulp is also waste paper, the quality will vary greatly. Moreover, deinked pulp usually contains a fluorescent dye, and if its content exceeds 20% by mass, it will contain a lot of fluorescent dye, which is not preferable.

If 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 under the UV-cut condition becomes large. Here, UV-in is a whiteness degree based on ISO 2470 when a C light source (including ultraviolet light) defined by CIE (International Commission on Illumination) is irradiated on the sheet surface side. UV-cut is the whiteness based on ISO 2470 when a C light source is irradiated on the sheet surface side through a filter that cuts ultraviolet light having a wavelength of 420 nm or less. 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, still more preferably 0.0 to 1.0 points, and most preferably 0.0 to 0.5 points. It is. The whiteness can be measured using a high-speed spectrophotometer CMS-35SPX manufactured by Murakami Color Research Laboratory Co., Ltd. according to ISO 2470.

  In addition, in order to ensure an appropriate strength for the toilet paper, raw materials can be blended by ordinary means, and the strength can be adjusted by beating the pulp fibers. As the beating to obtain the target quality, 0 to 200 ml, more preferably 0 to 150 ml, and more preferably 10 to 100 ml of a Canadian standard freeness measured by JIS-P8121 is used for commercially available virgin pulp. Reduce water content.

Toilet paper can be made by blending softwood kraft pulp and hardwood kraft pulp having a certain range of fiber length and fiber roughness in a specific range when virgin raw materials are used for the stock. Additives to paper stocks include softeners including debonder softeners, bulking agents, dyes, dispersants, dry paper strength enhancers, drainage improvers, pitch control agents, absorbency, depending on the required quality of the final product. An improver or the like can be used. Moreover, it is preferable not to use a wet paper strength enhancer.
When using waste paper raw material as toilet paper, the same treatment as in the case of the virgin is performed.
Details of the method for manufacturing toilet paper will be described later.

  Toilet paper can be manufactured, for example, in the following order: (1) papermaking and creping, (2) calendering, (3) embossing and roll winding. Of these, (3) has already been described and will be omitted.

(1) Papermaking and creping,
First, a web is made from the above-mentioned stock on a wire part of a known paper machine, and moved to the felt of the press part. Examples of the wire part type include a round net type, a long net type (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 with a suction pressure roll or a pressure roll or a press roll without suction, or dehydrated by a dehydration method such as aeration drying with hot air. The suction pressure roll or the pressure roll without suction is also used as a means for moving the web from the press part to the Yankee dryer.

The web moved to the Yankee dryer is dried by a Yankee dryer and a Yankee dryer hood, then creped by a creping doctor, and taken up by a reel part.
Creping (creating a wavy wrinkle called crepe) is to mechanically compress paper in the longitudinal direction (the sheet running direction on the paper machine). When the toilet paper web is manufactured, the web on the Yankee dryer is peeled off by the creping doctor and wound on the reel part. The speed difference between the Yankee dryer and the reel part (reel part speed ≤ Yankee dryer speed) ), A crepe is formed by a creping doctor.
The quality required for the toilet paper, that is, bulk (bulk feeling), softness, water absorption, surface smoothness, aesthetics (crepe shape), and the like depend on the speed difference. Although depending on conditions such as the speed difference, the basis weight of the web on the reel after creping is approximately 14 to 20 g / m ² , which is heavier than the basis weight of the web on the Yankee dryer before creping. The basis weight is preferably 14 to 19 g / m ² , more preferably 15 to 18 g / m ² . If it exceeds the above range, the strength may be high and the paper may be stiff. If it is less than the above range, the strength may be weak and easy to tear.

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 × (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 for those skilled in the art. In the present invention, the crepe rate when producing toilet paper is preferably 10 to 50%, more preferably 15 to 40%, and most preferably 20 to 35%.

(2) Ply-up and calendar processing by machine winder FIG. 7 shows an example of a machine winder 100. As described above, two reels 1 wound up by the reel part after creping are set on the machine winder 100, and the two reels 1 are overlapped with each other so that the Yankee surface is on the outside. At this time, the calendar processing is performed in two stages in order of the calendar machine 101 of the first stack and the calendar machine 102 of the second stack after the ply-up. Of course, only one stage of calendar processing may be performed on either the first stack calendar machine 101 or the second stack calendar machine 102. It is also possible to perform calendar processing with an on-machine calendar.
The thickness of the toilet paper before embossing (after calendaring) is preferably 0.5 to 1.4 mm / 10, more preferably 0.6 to 1.2 mm / 10, and even more preferably 0.6 to 0. .9mm / 10 sheets. Moreover, the specific volume of the toilet paper in the raw fabric roll 4 before the embossing process (after the calendar process) is preferably 3.4 to 6.5 cm ³ / g, more preferably 3.7 to 6.0 cm ³ / g, Preferably it is 4.0-5.5 cm < ³ > / g.

In addition, the paper thickness of the toilet paper before embossing is the paper thickness in the original fabric roll 4 after calendar processing in FIG. 7, and corresponds to the paper thickness t1 in FIG. However, as will be described later, since the paper thickness is a value measured with a measurement load of 3.7 kPa, it does not accurately reflect the paper thickness t1 in FIG.
The thickness of the toilet paper after embossing shown in Tables 1 and 2 corresponds to the paper thickness t2 in FIG. 2, but is a value measured at a measurement load of 3.7 kPa, so it accurately reflects the paper thickness t2. It was n’t.
On the other hand, the depth (emboss depth) D of the concave and convex portions of the unevenness is a value in a state where the emboss is not compressed. Therefore, the depth D of the concave and convex portions is significantly larger than a value calculated from the paper thicknesses t1 and t2 (this value is a value obtained by compressing embossing with a measured load of 3.7 kPa).

Each of the calender machines 101 and 102 is preferably composed of two metal rolls, but one of the two rolls may be an elastic roll so that soft calender processing can be performed.
The linear pressure of the calendar is preferably 3.0 to 8.0 kgf / cm, more preferably 4.0 to 7.0 kgf / cm. When the linear pressure exceeds the above range, the bulk becomes small and the softness may be inferior. Further, if the wire thickness is less than the above range, the bulk becomes large and the roll diameter DR of the roll becomes large. The linear pressure is preferably higher than the first stack.
During calendar processing, the draw can be adjusted appropriately. The draw between the reel 1 before ply-up and the original fabric 4 after the calendar process is preferably 100 to 110%.

  The raw fabric 4 after the calendar process is embossed by, for example, the roll winder 150 shown in FIG. Note that the winding density is obtained when the roll winding machine 150 of FIG. 3 winds the sheets sequentially by pressing the original roll 10W from the outer peripheral side when the winding mechanism 153 winds the wide toilet paper roll 10W. It can be adjusted by setting the pressing force of the rider roll 154 within a predetermined range.

  It goes without saying that the present invention is not limited to the above-described embodiments, and extends to various modifications and equivalents included in the spirit and scope of the present invention.

  The content ratio of the pulp composition is (mass%) NBKP 10%, LBKP 60%, waste paper pulp derived from milk carton, and 30% waste paper pulp. The apparatus shown in FIGS. Toilet paper and toilet rolls shown in Table 3 were produced.

The following evaluation was performed.
Measures the maximum load until break for toilet paper (2 plies) based on JIS P8113, the longitudinal tensile strength DMDT during drying and the transverse tensile strength DCDT during drying of the perforation and other parts did. Specific test pieces and measurement methods are as described above.
Basis weight: Measured based on JIS P8124, per sheet.
Paper thickness: measured using a thickness gauge (a dial thickness gauge “PEACOCK” manufactured by Ozaki Seisakusho). The measurement conditions were a measurement load of 3.7 kPa and a probe diameter of 30 mm. A sample was placed between the probe and the measurement table, and the gauge was read when the probe was lowered at a speed of 1 mm or less per second. The web and roll before and after the calendering were measured with 10 sheets stacked (5 sets of 2 plies). The measurement was repeated 10 times and the measurement results were averaged. Then, the average value obtained per time was divided by the number of sheets to obtain the paper thickness per sheet.

Specific volume: The thickness per sheet was divided by the basis weight per sheet, and expressed as a volume cm ³ per unit g.
Roll mass and core mass: Measured using an electronic balance. The measurement measured 10 rolls and averaged the measurement results.
Roll winding diameter DR, core outer diameter DI: Measured using a Diameter Rule manufactured by Muratec KDS Corporation. The measurement measured 10 rolls and averaged the measurement results.
The winding density and embossing depth D of the roll were measured by the above-described methods. In addition, the winding density of the roll measured 10 rolls used for the measurement of the roll diameter DR of the roll, and averaged the measurement results.

Sensory evaluation was performed by 20 monitors. The evaluation standard was a perfect score. If the evaluation criteria is 3 points or more, it is good.
The basis weight, tensile strength, thickness (paper thickness), roll mass and core mass, specific volume, winding diameter DR, core outer diameter DI, winding density, and emboss depth are measured in JIS-P8111. It was carried out after maintaining the equilibrium state under the specified temperature and humidity conditions (23 ± 1 ° C., 50 ± 2% RH).

  The obtained results are shown in Tables 1 to 3.

  As is apparent from Tables 1 to 3, in each example in which the roll length, roll diameter, and perforation strength (DMDT) of the toilet roll are in a predetermined range, the softness of the sheet without reducing the basis weight. The roll length per roll was increased and the perforation was easily cut from the beginning to the end of the roll.

On the other hand, in the case of Comparative Example 1 in which the winding length was less than 63 m, the winding diameter was less than 100 mm, and the roll mass was less than 200 g, the roll replacement frequency increased.
In the case of Comparative Example 2 in which the winding length exceeded 105 m, the winding diameter exceeded 140 mm, and the roll mass exceeded 400 g, the roll diameter increased and it was difficult to fit in the toilet paper holder.

In the case of Comparative Examples 3, 5, 7, and 9 in which the perforation strength (DMDT) is less than 3.6 N / 114 mm, the perforation was inadvertently cut at the beginning of use of the roll, and could not be cut to the required length. .
In Comparative Example 3, the toilet paper that does not contain perforations has a DMDT of less than 11 N / 114 mm, and the strength of the toilet paper itself is low, so that the perforation strength is reduced and the sheet itself is easily broken.
On the other hand, in Comparative Examples 5 and 7, the DMDT of toilet paper that does not include perforations is 11 N / 114 mm or more, and the strength of the toilet paper itself is ensured, but the perforation bond rate is 20%. The strength of was reduced.

  In Comparative Example 9 where the emboss depth exceeded 0.45 mm, the DMDT of toilet paper not containing perforations was 11 N / 114 mm or more, and the strength of the toilet paper itself was ensured, but the emboss depth was 0.45 mm. The perforation strength decreased because of exceeding, and the perforation was cut carelessly at the beginning of use of the roll, and could not be cut to the required length. Moreover, in the case of the comparative example 9, the winding diameter exceeded 140 mm and it became difficult to fit in a toilet paper holder.

In Comparative Examples 4, 6, and 8 in which the perforation strength (DMDT) exceeded 14.8 N / 114 mm, the perforation was difficult to cut at the end of use of the roll.
In Comparative Example 4, the DMDT of toilet paper not containing perforations exceeded 30 N / 114 mm, and the strength of the perforations was too high because the strength of the toilet paper itself was too high. Also, the sheet itself was hard and inferior in softness.
On the other hand, in Comparative Examples 6 and 8, DMDT of toilet paper that does not contain perforations is appropriate, and the strength of the toilet paper itself is in an appropriate range, but the perforated bond rate exceeds 80%, so The strength was too high.

  In the case of Comparative Example 10 manufactured under the same manufacturing conditions as Example 17 except that no embossing was provided, the perforation strength was too high compared to Example 17 because there was no embossing. Also, the sheet itself was hard and inferior in softness.

  In addition, when it evaluated similarly about the commercial item 1-2, the winding length was less than 63 m and the replacement | exchange frequency of the roll increased.

2 Embossed
10 Toilet roll 10m Perforation 10m1 Perforation part of perforation 10m2 Perforation line 10x Toilet paper D Emboss depth (depth of recess)

Claims (8)

A toilet roll in which one surface is a convex portion and a corresponding opposite surface has a plurality of concave and convex portions, and a 2-ply toilet paper having a perforation along the width direction is wound into a roll shape,
Longitudinal direction at the time of drying of two plies based on JIS P8113 of perforation per roll width of 114 mm, roll diameter of 63 to 105 m, roll diameter of 100 to 140 mm, roll including core per roll width of 114 mm, 200 to 400 g A toilet roll having a tensile strength DMDT of 3.6 to 14.8 N / 114 mm. The toilet roll according to claim 1, wherein the depth of the concave and convex portions is 0.03 to 0.45 mm. The toilet roll according to claim 1, wherein a ratio represented by (DMDT of the perforation) × 1000 / (the roll mass) is 13 to 53 N / (114 mm × g). The toilet roll according to any one of claims 1 to 3, wherein a 2-ply DMDT of the toilet paper not including the perforation is 11 to 30 N / 114 mm. The bond rate represented by {the length of the splinter part / (the length of the splinter part + the length of the cut line)} × 100 of the perforation is 20 to 80%. The toilet roll according to one item. The toilet roll according to any one of claims 1 to 5, wherein a length of the perforated part of the perforation is 0.3 to 2.7 mm. The toilet roll according to any one of claims 1 to 6, wherein the perforation line has a length of 0.4 to 3.3 mm. The toilet roll according to any one of claims 1 to 7, wherein the irregularities are embossed.