JP2018015259A - Toilet roll - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a long toilet roll in which a texture is superior and in which a core is made hardly crushed without impairing cost and productivity.SOLUTION: The toilet roll 10 is two-ply toilet paper 10x taken up in a roll, having a plurality of projecting and recessing parts in which one surface is projected and the corresponding opposite surface is recessed. The toilet roll has a wound length of 63-105 m, a wound diameter of 100-140 mm, a roll weight per roll width 114 mm containing no core of 200-400 g, a core weight per roll width 114 mm of 3.0-5.5 g, a core outer diameter of 25-48 mm, and a roll density of 0.13-0.30 g/cm.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, in general, a toilet roll rolls up a log with a length of a product and a width of several meters, and then cuts it into round pieces with a product width in the axial direction of the log with a log saw, and a large number of toilet rolls are made from one log. Manufactured.
On the other hand, in order to make a long toilet roll with a limited winding diameter, it may be solidly wound, but if it is wound too tightly, the core will be crushed when cutting with a log saw. Moreover, when unevenness | corrugation (embossing) is not provided in the sheet | seat of toilet paper, since there is no space | gap between sheets, it becomes more solid winding and a touch feeling is also inferior. 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 will be large and it will be difficult to attach it to the paper holder.

On the other hand, if the log is wound by the product width, the log saw is not required to be cut, and the problem that the core is crushed is solved. However, this method cannot be adopted because the productivity is greatly reduced.
In addition, if the core diameter is increased, it becomes difficult for the sheet to sag at the beginning of winding of the sheet (where it is wound around the core) at the time of log production, so it is possible to increase the processing speed and improve productivity. It becomes easy to be crushed.

On the other hand, if the toilet roll 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 the last part (starting winding) ) Is hard and does not come loose, making it difficult to unwind. Moreover, when the core is made small in diameter, it becomes difficult to attach to the toilet holder.
Further, if the mass of the core is increased (the basis weight of the core is increased), the core is difficult to be crushed, but the core becomes hard and the productivity of the core is reduced or the cost is increased.
As mentioned above, when manufacturing the long toilet roll which has a core, it was difficult to make a core difficult to crush without impairing cost and productivity.

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

The inventors of the present invention have found that the roll density of the roll is important as a factor that makes it difficult to collapse the core when manufacturing a toilet roll. In other words, if the winding density is too high, the core will be easily crushed due to solid winding (mass per volume is high). On the other hand, if the winding density is low, the core will not be crushed, but the winding diameter will increase and the toilet paper holder etc. It becomes difficult to fit in.
Also, by regulating the core mass, it was possible to suppress core productivity decline and cost increase, and by regulating the outer diameter of the core, the toilet roll productivity was improved while preventing the core from collapsing. .

In order to solve the above-mentioned problems, the toilet roll of the present invention is a toilet roll in which two-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 is wound into a roll shape. The roll length is 63 to 105 m, the roll diameter is 100 to 140 mm, the roll mass not including the core per roll width 114 mm is 200 to 400 g, the mass of the core per roll width 114 mm is 3.0 to 5.5 g, The outer diameter of the core is 25 to 48 mm, and the winding density of the roll is 0.13 to 0.30 g / cm ³ .

The depth of the concave and convex portions is preferably 0.01 to 0.45 mm.
It is preferable that the core has a hardness of 0.8 to 4.0 mm.
It is preferable that the apparent basis weight of the core is 230 to 420 g / m ² .
The ratio represented by (hardness of the core) / (winding density of the roll) is preferably 2.8 to 16.5 mm / (g / cm ³ ).
It is preferable that the tensile strength DMDT in the longitudinal direction at the time of drying based on JIS P8113 of the toilet paper is 2.5 to 7.0 N / 25 mm.
It is preferable that the tensile strength DCDT in the transverse direction at the time of drying based on JIS P8113 of the toilet paper is 0.7 to 2.2 N / 25 mm.
It is preferable that the unevenness is embossed.

  According to the present invention, it is possible to obtain a long toilet roll that has a good tactile sensation and that does not easily collapse the core without impairing cost and productivity.

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 measurement of the emboss depth in case an 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 a two-ply toilet paper 10x having a plurality of irregularities is wound around a core 5 in a roll shape, Winding length) is 63 to 105 m, winding diameter DR is 100 to 140 mm, roll mass not including core 5 per roll width 114 mm is 200 to 400 g, and mass of core 5 per roll width 114 mm is 3.0 to 5 0.5 g, the outer diameter of the core 5 is 25 to 48 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 108 to 135 mm, more preferably 115 to 123 mm.

The roll mass not including the core (winding core) 5 per 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 the roll replacement frequency is increased. When the roll mass exceeds 400 g, the roll diameter becomes large and it is difficult to fit in the toilet paper holder.
The roll mass is preferably 230 to 350 g, more preferably 250 to 330 g.

The mass of the core 5 with a roll width W of 114 mm is 3.0 to 5.5 g. The conversion method of 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 3.0 g, the basis weight of the core 5 is small, and the core is easily crushed when a toilet roll (log) is manufactured. If the mass of the core 5 exceeds 5.5 g, the basis weight of the core 5 becomes high, so that the core is difficult to be crushed, but the core becomes hard, leading to a decrease in core productivity and an increase in cost.
The mass of the core 5 is preferably 3.6 to 5.0 g, and more preferably 4.1 to 4.6 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 not easily crushed, but the toilet roll is difficult to be attached to the toilet holder. When the outer diameter of the core 5 exceeds 48 mm, the core is liable to be crushed when a toilet roll (log) is manufactured.
The outer diameter of the core 5 is preferably 35 to 46 mm, and more preferably 37 to 43 mm.

The roll has a winding density of 0.13 to 0.30 g / cm ³ , preferably 0.17 to 0.28 g / cm ³ , and more preferably 0.22 to 0.26 g / cm ³ .
When the roll is wound too hard (the winding density is too high), the core is easily crushed due to the solid winding (the mass per volume is high). 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 (roll mass not including core) / (roll volume). The roll mass is the mass of the toilet roll 10 in which the roll width W is converted per 114 mm. The roll volume is represented by [{the cross-sectional area of the outer diameter of the roll (winding diameter DR) portion) − (the cross-sectional area of the core outer diameter portion)} × the roll width (assumed to be 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 = 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 0.13 g / cm ³ , 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. If the winding density exceeds 0.30 g / cm ³ , the core is easily crushed due to solid winding. In addition, the softness of the sheet may be inferior, and the embossing provided on the toilet paper may be crushed, resulting in a decrease in cosmetic properties during use.

<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. In addition, when double embossing is performed, it is possible to make two plies by edge embossing or glue, but edge embossing is preferable because the sheet feels soft.
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. 2 (a), since the embossing depth D is increased, it is necessary to reduce the paper thickness t1 per sheet and 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 adjacent portion of the convex portion and the concave portion. 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. 8, 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 is not obtained, and the depth D of the recess 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 0.01 to 0.45 mm, more preferably 0.04 to 0.40 mm, and still more preferably 0.08 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.

The hardness of the core 5 is preferably 0.8 to 4.0 mm, more preferably 1.4 to 3.3 mm, and still more preferably 1.8 to 2.9 mm.
When the hardness of the core is less than 0.8 mm, the productivity of the core may be inferior. This is because the strength becomes too high due to reasons such as high basis weight of the core, and it becomes difficult to bend the core sheet into a cylindrical shape. When the hardness of the core exceeds 4.0 mm, the core may be crushed when a toilet roll is manufactured. This is because the strength becomes too low due to the low basis weight of the core, and the core tends to be crushed.

The hardness of the core 5 is measured as follows using a compression tester (a handy compression tester KES-G5 manufactured by Kato Tech Co., Ltd.). First, the core 5 is placed on a hard table so that the axis is horizontal. Next, the KES-G5 compressor (area 2.0 cm ² ) is pushed into the center portion of the outer surface of the core 5 from above under the condition of a speed of 10 mm / min. The indentation depth when the pressure at which the compressor pushes the roll is 0.5 gf / cm ² is T0, the indentation depth when the pressure is 250 gf / cm ² is Tm, and (Tm−T0) is the hardness of the core 5 To do. A large value means that the core tends to collapse. The measurement is performed 5 times using 5 cores (measured once for each core), and the measurement results are averaged.

The ratio represented by (hardness of the core) / (winding density of the roll) is preferably 2.8 to 16.5 mm / (g / cm ³ ), more preferably 5.5 to 13.5 mm / ( g / cm ³ ), more preferably 8.0 to 11.5 mm / (g / cm ³ ).
When the winding density is within the above range and the ratio is less than 2.8 mm / (g / cm ³ ), the core hardness value with respect to the winding density is low, and the core strength is higher than necessary. This may increase the cost of the core.
When the winding density is within the above range and the ratio exceeds 16.5 mm / (g / cm ³ ), the core hardness value with respect to the winding density is high, and the core may be easily crushed.

The apparent mass of the core 5 is preferably 230 to 420 g / m ² , more preferably 270 to 370 g / m ² , still more preferably 290 to 330 g / m ² . When the apparent mass of the core 5 is less than 230 g / m ² , the core may be crushed when a toilet roll is manufactured. On the other hand, when the apparent mass of the core 5 exceeds 420 g / m ² , the strength of the core becomes higher than necessary, which may increase the cost of the core or deteriorate the productivity of the core.
The apparent basis weight of the core is expressed by (mass of the core) ÷ (outer surface area of the 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 a part where the two core base papers are partially overlapped and thickened. Since it is different from the wound one, the “apparent” basis weight is used.

Sheet (toilet paper) Tensile strength (MD) in dry direction (MD) based on JIS P8113 of 10x is preferably 2.5 to 7.0 N / 25 mm, more preferably 3.0. ˜5.8 N / 25 mm, more preferably 3.5 to 4.5 N / 25 mm.
DMDT is a strip shape in which the MD direction (longitudinal direction perpendicular to the width W) of the sheet (toilet paper) 10x is 250 mm long, and a test piece having a width W of 25 mm is cut out and measured. The distance between the gripping tool and the gripping tool of the tensile tester is 100 mm, and measurement is performed by pulling in the MD direction under the condition of a tensile speed of 300 mm / min. At this time, a perforation is not included in a portion having a distance of 100 mm between the gripping tool and the gripping tool.

Toilet paper 10x has a dry cross direction tensile strength (CDDT) of 0.7 to 2.2 N / 25 mm, more preferably 0.8 to 1.2. It is 8 N / 25 mm, more preferably 1.0 to 1.5 N / 25 mm.
DCDT is a strip shape with the CD direction (longitudinal direction parallel to the width W) of the sheet (toilet paper) 10x having a longitudinal direction of 114 mm (sheet width), and a test piece having a width W of 25 mm is cut out and measured. To do. The distance between the gripping tool and the gripping tool of the tensile tester is 100 mm, and 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 set as the roll width. In addition, when the roll width (sheet width) is small and the distance between the gripping tool and the gripping tool cannot be secured 100 mm, this spacing is set as {(roll width) − (length holding the sheet with the gripping tool × 2)} mm. Also good.

If DMDT or DCDT is less than the above value, it may be easily blurred and not suitable for practical use. When DMDT or 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 basis weight per sheet of toilet paper 10x is preferably 13.0 to 19.0 g / m ² , more preferably 13.5 to 17.0 g / m ² , and even more preferably 14.1 to 16.0 g / m ² . a m ^2.
The sheet thickness is preferably 0.45 to 1.20 mm / 10, more preferably 0.55 to 1.05 mm / 10, and still more preferably 0.65 to 0.90 mm / 10.
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 less than 13.0 g / m ² or the paper thickness is less than 0.45 mm / 10 sheets, the strength decreases and the feeling of use (bulkiness) also occurs. May decrease. If the basis weight per piece of toilet paper 10x exceeds 19.0 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 toilet paper holder.

The specific volume of the toilet paper is preferably 3.0 to 7.5 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, when the specific volume exceeds 7.5 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 raw paper roll is subjected to a calendar process to become a raw fabric 114 (sheet thickness t1 of the sheet). This raw fabric 114 is set on a roll winder 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-mentioned winding diameter by a winding mechanism 153. Taken and logs. Thereafter, 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 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.
7 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 is processed. The machine may perform calendar processing and emboss processing 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 targeted quality, the content of NBKP (conifer bleached kraft pulp) is preferably 0 to 30% by mass, more preferably 0 to 20% by mass, and still more 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 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 still more preferably 20 to 45% by mass. Preferably, it is 40-100 mass%, More preferably, it is 50-90 mass%, More preferably, it is 55-80 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 21 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) Calendar processing FIG. 7 shows an example of the machine winder 100. As described above, two reels 112 wound up by the reel part after creping are set on the machine winder 100, and the two reels 112 are overlapped and plyed up so that the Yankee surface is on the outside, thereby forming an original fabric roll 114. 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. The specific volume of the toilet paper in the original fabric 114 before embossing (after calendaring) is preferably 3.4 to 6.5 cm ³ / g, more preferably 3.7 to 6.0 cm ³ / g, and even more preferably Is 4.0 to 5.5 cm ³ / g.

In addition, the paper thickness of the toilet paper before embossing is the paper thickness in the original fabric 114 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 112 before the ply-up and the original fabric 114 after the calendar process is preferably 100 to 110%.

  The original fabric 114 after the calendar process is embossed by, for example, the roll winder 150 shown in FIG. Note that the winding hardness (and winding density) is determined by pressing the original roll 10W from the outer peripheral side when the roll winding machine 150 in FIG. The pressing force of the rider roll 154 for sequentially winding the seats can be adjusted by setting 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.
The maximum tensile load until breakage was measured for toilet paper (2 ply state) based on the tensile strength in the vertical direction DMDT during drying and the lateral tensile strength DCDT in drying: JIS P8113. 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. In addition, about the web and roll before and after a calendar process, all 10 sheets were piled up and it measured. 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.
The mass of the roll not including the core and the mass of the core were 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 roll winding density, emboss depth D, and core hardness were measured by the methods described above. 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.
Winding length: About the sheet | seat between perforations, the length for 10 sheets was measured. Thereafter, the number of roll sheets was measured. It was obtained 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 330 sheets, 2.275 m × (330/10) = 75 m.

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.
Basis weight, tensile strength, thickness (paper thickness), roll mass and core mass, specific volume, winding diameter DR, core outer diameter DI, core hardness, winding density, winding length, emboss depth The measurement of was carried out after maintaining the equilibrium state under the temperature and humidity conditions specified in JIS-P8111 (23 ± 1 ° C., 50 ± 2% RH).

  The obtained results are shown in Tables 1 to 3.

As apparent from Tables 1 to 3, the roll length of the toilet roll, the roll diameter, the roll mass not including the core, the mass of the core, the winding density of the roll, and the outer diameter of the core are within the predetermined ranges. In this case, the tactile sensation was good, the winding length per roll was increased, and the core could not be easily crushed without deteriorating cost and productivity.
Further, in each example in which the sheet strength (DMDT) is 2.5 to 7.0 N / 25 mm, the sheet is torn compared to Example 22 in which the sheet strength (DMDT) is less than 2.5 N / 25 mm. The hardness was excellent. However, Example 22 has no practical problem.
In each example in which the sheet strength (DMDT) is 2.5 to 7.0 N / 25 mm, the sheet is softer than the example 23 in which the sheet strength (DMDT) exceeds 7.0 N / 25 mm. Was excellent. However, Example 23 has no practical problem.

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 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 less crushed than Comparative Example 9.

In the case of Comparative Example 4 in which the core hardness was less than 0.8 mm, the core productivity was inferior.
In the case of Comparative Example 3 in which the hardness of the core exceeded 4.0 mm, the core was crushed when the toilet roll was manufactured.
In the case of Comparative Example 4, the ratio was less than 2.8 mm / (g / cm ³ ), the apparent basis weight of the core exceeded 420 g / m ² , and the core cost was increased.

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

In the case of Comparative Example 7 produced under the same production conditions as in Example 18 except that no embossing was provided, the sheet was harder and softer than Example 18 because of no embossing. Further, the winding density exceeded 0.30 g / cm ³ and the core was crushed.

In the case of Comparative Example 8 in which the emboss depth exceeded 0.45 mm, the roll became too bulky and the winding diameter exceeded 140 mm, and the roll diameter became large, making it difficult to fit in the toilet paper holder. In Comparative Example 8, the winding density was less than 0.13 g / cm ³ .

In Comparative Examples 3 and 6, the ratio exceeded 16.5 mm / (g / cm ³ ), and the core was easily crushed.

  In addition, when similarly evaluated about the commercial item 1-2, the winding length was less than 105 m and the replacement | exchange frequency of the roll increased.

2 Embossed
10 Toilet roll 10x Toilet paper D Emboss depth (depth of recess)

Claims (8)

A toilet roll in which a roll of two-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,
The roll length is 63 to 105 m, the roll diameter is 100 to 140 mm, the roll mass not including the core per roll width 114 mm is 200 to 400 g, the core mass per roll width 114 mm is 3.0 to 5.5 g, Outer diameter is 25-48mm,
A toilet roll having a roll winding density of 0.13 to 0.30 g / cm ³ . The toilet roll according to claim 1, wherein a depth of the concave and convex portions is 0.01 to 0.45 mm. The toilet roll according to claim 1 or 2, wherein the core has a hardness of 0.8 to 4.0 mm. Toilet rolls according to any one of claims 1 to 3 basis weight of apparent of the core is 230~420g / ^{m 2.} The ratio represented by (hardness of the core) / (winding density of the roll) is 2.8 to 16.5 mm / (g / cm ³ ). 5. Toilet roll. The toilet roll according to any one of claims 1 to 5, wherein the toilet paper has a longitudinal tensile strength DMDT of 2.5 to 7.0 N / 25 mm when dried based on JIS P8113. The toilet roll according to any one of claims 1 to 6, wherein the toilet paper has a transverse tensile strength DCDT of 0.7 to 2.2 N / 25 mm when dried based on JIS P8113. The toilet roll according to any one of claims 1 to 7, wherein the irregularities are embossed.