JP7028525B2 - Toilet roll - Google Patents

Description

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

Toilet rolls are mainly packaged in units of 4 rolls, 12 rolls, etc. on the market. Since these packages are bulky, the amount that can be carried at the time of purchase is limited, and the amount that can be purchased at one time is naturally limited. In addition, when storing at home, workplace, public facilities, etc., the storage space is limited, so the amount that can be stored is also limited.

For these reasons, 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 lengthened (Patent Documents 1 and 2).

In addition, the applicant has developed a toilet roll having a longer winding length while improving the texture and usability by increasing the basis weight per sheet of toilet paper to 13 g / m ² (Patent Documents 3 and 4). ).

Japanese Unexamined Patent Publication No. 2006-08703 Japanese Unexamined Patent Publication No. 2013-208297 Japanese Unexamined Patent Publication No. 2014-188342 Japanese Unexamined Patent Publication No. 2014-233363

However, when the basis weight of the paper is lowered, the strength is lowered and the usability and bulkiness are lowered. On the other hand, in order to increase the bulk of the paper to compensate for these problems, if the calendering process is weakened, there is a problem that the smoothness is inferior or the roll diameter becomes large and it becomes difficult to fit in the toilet paper holder.

Further, in the inventions described in Patent Document 3 and Patent Document 4, the texture is improved while increasing the basis weight of the toilet paper, and the softness of the sheet is ensured, but the softness of the roll is examined. It has not been. Here, the softness of the roll is the tactile sensation when the toilet roll is held in the hand at the store, and does not directly reflect the softness of the sheet. This is because the softness of the sheet is important when using the toilet roll, but it is not possible to check the softness of the sheet by unwinding the roll at the store. Therefore, if the roll is hard, even if the sheet itself is soft, the sheet is considered to be hard, and there is a problem that the purchase cannot be promoted.

Therefore, according to the present invention, the softness of the sheet and the roll is improved without lowering the basis weight, and the winding length per roll is lengthened to enhance the sales promotion effect due to the good softness, while carrying the amount and storage. The purpose is to provide a toilet roll with excellent space saving.

In view of the above problems, the present inventors have conducted diligent research. As a result, in the toilet roll obtained by winding the 1-ply toilet paper into a roll shape, an embossing pattern is provided on the toilet paper, and the winding length, winding diameter, winding density and roll density of the toilet roll are adjusted to predetermined values. As a result, it was found that the above problems could be solved, and the present invention was completed. Specifically, the present invention provides the following.
(1) The first aspect of the present invention is a toilet roll in which 1-ply toilet paper is wound into a roll shape, in which an embossed pattern is provided on the toilet paper, and the winding length of the toilet roll is 105 m or more and 210 m or less. A toilet roll having a winding diameter of 107 mm or more and 140 mm or less, a winding density of 1.1 m / cm ² or more and 1.9 m / cm ² or less, and a roll density of 0.21 g / cm ³ or more and 0.37 g / cm ³ or less. ..
(2) In the toilet roll according to (1), the depth of the embossing pattern may be 0.01 mm or more and 0.35 mm or less.
(3) In the toilet roll according to (1) or (2), the toilet paper may contain kraft pulp in an amount of 40% by mass or more and 100% by mass or less.
(4) In the toilet roll according to any one of (1) to (3), the toilet paper may contain 0% by mass or more and 60% by mass or less of used paper pulp derived from a milk carton.
(5) In the toilet roll according to any one of (1) to (4) above, the ISO 2470 when the surface side of the toilet paper is irradiated with the C light source specified by the CIE (International Commission on Illumination) is compliant. Difference between whiteness UV-in and ISO 2470-compliant whiteness UV-cut when the C light source is applied to the surface side of the toilet paper via a filter that cuts ultraviolet light having a wavelength of 420 nm or less. May be 0.0 points or more and 2.5 points or less.

According to the present invention, by providing the embossed pattern on the toilet paper, the softness of the toilet paper is improved without lowering the basis weight of the toilet paper. Further, by adjusting the winding length, winding diameter, winding density and roll density of the toilet roll to predetermined values, a toilet roll having a long winding length per roll and excellent softness can be obtained. Therefore, it is possible to obtain a toilet roll that is excellent in a portable amount and space saving during storage, while enhancing the sales promotion effect due to its good softness.

It is a perspective view which shows the appearance of the toilet roll which concerns on 1st Embodiment of this invention. It is a figure which shows the photographed image of the embossing pattern on the roll surface side. It is sectional drawing which shows the embossing pattern provided on the front surface and the back surface of a roll. It is a figure which shows the measuring method of the depth of the embossing pattern. It is a figure which shows the measuring method of the depth of the embossing pattern. It is a figure which shows the measuring method of the depth of the embossing pattern. It is a figure which shows the measuring method of the depth of the embossing pattern. It is a figure which shows an example of a machine winder. It is a figure which shows an example of a roll winding processing machine.

The embodiments of the present invention will be described in detail below, but these are listed for the purpose of illustration and do not limit the present invention.

[Toilet roll]
As shown in FIG. 1, the toilet roll 1 according to the first embodiment of the present invention is a roll of 1-ply toilet paper.

<Volume length>
The winding length of one roll of the toilet roll 1 of the present invention, that is, the total length when the toilet roll 1 is unfolded is 105 m or more and 210 m or less, preferably 130 m or more and 190 m or less, and 150 m or more and 170 m or less. More preferred. Rolls wound to a length within the above numerical range are cut to a predetermined width to produce one roll of toilet roll 1.

<Volume diameter>
As shown in FIG. 1, the winding diameter DR in the toilet roll 1 of the present invention is preferably 107 mm or more and 140 mm or less, preferably 110 mm or more and 135 mm or less, and more preferably 117 mm or more and 125 mm or less.

<Volume density>
The winding density in the toilet roll 1 is expressed by (winding length × number of plies) ÷ (cross-sectional area of the roll). The cross-sectional area of the roll is represented by {cross-sectional area of the outer diameter (roll diameter DR) portion of the roll}-(cross-sectional area of the core outer diameter portion). For example, when the winding length is 150 m, 1 ply, the winding diameter is 117 mm, and the outer diameter of the core is 39 mm, the winding density = (150 m × 1) ÷ {3.14 × (117 mm ÷ ² ÷ 10) 2-3.14 × (39 mm). ÷ 2 ÷ 10) ² } = 1.57 m / cm ² .

Here, the core refers to the winding core of the toilet roll, and the core outer diameter is the diameter of the center hole of the roll.

The winding density of the toilet roll 1 of the present invention is preferably 1.1 m / cm ² or more and 1.9 m / cm ² or less, preferably 1.2 m / cm ² or more and 1.8 m / cm ² or less. It is more preferably 3 m / cm ² or more and 1.6 m / cm ² or less.

<Roll density>
The roll density of the toilet roll 1 of the present invention is expressed by (roll mass excluding core) ÷ (roll volume). The roll mass is the mass of the toilet roll converted into a roll width W of around 114 mm. The roll volume is expressed by [{cross-sectional area of roll outer diameter (roll diameter) portion}-(cross-sectional area of core outer diameter portion)] × roll width (converted to around 114 mm). For example, when the roll mass per 114 mm of roll width is 305 g, the winding diameter is 117 mm, and the outer diameter of the core is 39 mm, the roll density = 305 g ÷ [{3.14 × (117 mm ÷ 2 ÷ 10) ² -3.14 × ( 39 mm ÷ 2 ÷ 10) ² } × (114 mm ÷ 10)] = 0.28 g / cm ³ . If the toilet roll does not have a core, the diameter of the central hole is the outer diameter of the core.

The roll density of the toilet roll 1 of the present invention is 0.21 g / cm ³ or more and 0.37 g / cm ³ or less, preferably 0.22 g / cm ³ or more and 0.34 g / cm ³ or less, and 0. It is more preferably 26 g / cm ³ or more and 0.30 g / cm ³ or less.

In the toilet roll 1 of the present invention, by setting the winding length and the winding diameter within the above numerical ranges, the amount that can be carried and the space saving during storage are good, and the ease of attachment to the toilet paper holder is also good. It can be a good toilet roll 1. Further, in the toilet roll 1 of the present invention, by keeping the winding density and the roll density within the above numerical ranges, the softness of the roll is good, and the adhesion between the core and the roll is also good. It can be 1. Therefore, by keeping the winding length, winding diameter, winding density, and roll density within the above numerical ranges, the toilet can be carried in a portable amount and has excellent space saving during storage, while enhancing the sales promotion effect due to its good softness. It can be roll 1. Further, since the toilet roll 1 of the present invention is a roll of 1-ply toilet paper, it is wound more even when the winding diameter is about the same as that of a 2-ply laminated toilet paper. Since the length can be increased, the toilet roll 1 can be made into a toilet roll 1 having an excellent portable amount and space saving during storage.

<Roll mass>
The roll mass of the toilet roll 1 of the present invention is a roll mass having a roll width W of 114 mm and does not include a core. When the roll width W is different from 114 mm, W is converted to 114 mm to obtain the roll mass. For example, when the roll width W is 105 mm, the mass obtained by multiplying the roll mass by a coefficient (114/105) is defined as the roll mass per 114 mm of W.

The roll mass of the toilet roll 1 of the present invention is preferably 235 g or more and 480 g or less, more preferably 250 g or more and 420 g or less, and further preferably 300 g or more and 350 g or less. In the toilet roll 1 of the present invention, by setting the roll mass within the above numerical range, it is possible to obtain a toilet roll 1 having a good winding length, winding diameter and mass per roll.

<Core outer diameter>
The outer diameter of the core of the toilet roll 1 of the present invention is preferably 25 mm or more and 48 mm or less, more preferably 35 mm or more and 46 mm or less, and further preferably 37 mm or more and 43 mm or less. In the toilet roll 1 of the present invention, by setting the core outer diameter to be within the above numerical range, the toilet roll 1 can be easily attached to the toilet paper holder and handled at the time of manufacture. can. The mass of the core of the toilet roll 1 is preferably 3.2 g or more and 6.0 g or less, more preferably 4.0 g or more and 5.5 g or less, and 4.5 g or more and 5.0 g or less. Is even more preferable. By keeping the core mass within the above numerical range, the strength of the core and the cost of the core suitable for a long toilet paper as in the present application can be improved. The mass of the core is the mass of the roll width of 114 mm, which is the same as the mass of the roll.

<Roll softness>
When evaluating the softness of the toilet roll 1 having a long winding length as in the present application, it is preferable to evaluate the softness of the roll when the roll is held in the hand by evaluating the roll softness described below.

The roll softness of the toilet roll 1 is measured as follows using a compression tester (Handy compression tester KES-G5 manufactured by Kato Tech Co., Ltd.). The direction parallel to the axis of the toilet roll 1 is the height direction, and the direction perpendicular to the tangent to the circumference of the toilet roll 1 is the radial direction.

First, an acrylic pipe is inserted into the core of the toilet roll 1. The wall thickness of the acrylic pipe is 2 mm. The length of the acrylic pipe is 10 mm longer than the roll width of the toilet roll 1 (when the roll width of the toilet roll 1 is 114 mm, the length of the acrylic pipe is 124 mm). The outer diameter of the acrylic pipe is slightly smaller than the inner diameter of the core of the toilet roll 1, and when the acrylic pipe is placed so that the axis of the toilet roll 1 is vertical after the acrylic pipe is inserted, the toilet roll does not move by its own weight. The size. If it is difficult to insert the acrylic pipe into the core and the outer diameter of the acrylic pipe is slightly reduced, the wall thickness may be slightly reduced with water resistant paper or the like. The mass of the acrylic pipe is about 31 g when the length is 125 mm and the outer diameter is 38 mm.

Next, the toilet roll 1 is placed sideways on a hard table so that the axis is horizontal. Then, the KES-G5 compressor (area 2.0 cm ² ) is pushed into the center of the toilet roll 1 in the height direction from above in the radial direction under the condition of a speed of 10 mm / min. The pushing depth when the pressure at which the compressor pushes the roll is 5 gf / cm ² is T0, the pushing depth when the pressure is 150 gf / cm ² is Tm, and (Tm-T0) is the roll softness. The measurement is performed 5 times and the measurement results are averaged. The height direction when the compressor is pushed into the toilet roll 1 does not have to be the central portion in the height direction except for both ends in the height direction. In the measurement of the roll softness of the toilet roll 1 of the present invention, the compressor is pushed into the vicinity of the middle between the center portion and the end portion of the toilet roll 1 in the height direction.

The roll softness of the toilet roll 1 of the present invention is preferably 0.2 mm or more and 1.7 mm or less, more preferably 0.3 mm or more and 1.4 mm or less, and 0.4 mm or more and 1.0 mm or less. It is more preferable to have.

[toilet paper]
The toilet paper in the toilet roll 1 of the present invention may be made of 100% by mass of wood pulp, and may contain used paper pulp, non-wood pulp, and deinked pulp. However, in order to obtain the target quality, the content of NBKP (coniferous bleached kraft pulp) is preferably 0% by mass or more and 30% by mass or less, and preferably 0% by mass or more and 20% by mass or less. It is more preferably 0% by mass or more and 10% by mass or less. The content of LBKP (hardwood bleached kraft pulp) is preferably 30% by mass or more and 90% by mass or less, more preferably 40% by mass or more and 80% by mass or less, and 50% by mass or more and 70% by mass or less. The following is more preferable.

The content of used paper pulp derived from a milk carton (milk carton) is preferably 0% by mass or more and 60% by mass or less, more preferably 10% by mass or more and 50% by mass or less, and 20% by mass or more and 45. It is more preferably mass% or less. The content of kraft pulp is preferably 40% by mass or more and 100% by mass or less, more preferably 50% by mass or more and 90% by mass or less, and 55% by mass or more and 80% by mass or less. Is even more preferable.

Recycled paper pulp derived from milk carton (milk carton) is mainly made of softwood pulp and has the advantage that it is easy to secure the strength of toilet paper. , It is preferable that the content is within the above numerical range.

As the grade of LBKP, pulp produced from the genus Eucalyptus, represented by the genus Eucalyptus and Eucalyptus globulus, is preferable.

Further, 25 parts by mass or less of deinked pulp derived from used newspaper, magazine, etc. can be blended with 100 parts by mass of used paper derived from NBKP, LBKP, and milk carton. When 25 parts by mass of deinked pulp is blended, the content of deinked pulp in the toilet paper (sheet) is 25 parts by mass / (100 parts by mass + 25 parts by mass) × 100 = 20% by mass. The content of the deinked pulp is preferably 0% by mass or more and 20% by mass or less, more preferably 0% by mass or more and 10% by mass or less, and further preferably 0% by mass or more and 5% by mass or less. It is preferably 0% by mass, and particularly preferably 0% by mass. Since deinked pulp is also recycled paper, the quality varies widely. Further, the deinked pulp usually contains a fluorescent dye, and if the content thereof exceeds 20% by mass, the deinked pulp contains a large amount of the fluorescent dye, which is not preferable.

In addition, in order to ensure the appropriate strength of the toilet paper, the raw materials can be blended by ordinary means, and the strength can be adjusted by beating the pulp fiber. As a beating to obtain the target quality, it is preferable to reduce the Canadian standard freeness measured by JIS-P8121 with respect to the commercially available virgin pulp, and the difference in the Canadian standard freeness before and after beating is 0 mL. It is preferably 150 mL or more, more preferably 10 mL or more and 100 mL or less, and further preferably 20 mL or more and 70 mL or less.

When a virgin raw material is used as a paper material, toilet paper can be made by blending softwood kraft pulp and broadleaf kraft pulp having a certain range of fiber length and fiber roughness in a specific range. As additives to paper materials, depending on the required quality of the final product, softeners including debonder softeners, bulking agents, dyes, dispersants, dry paper strength enhancers, drainage improvers, pitch control agents, absorbency An improver or the like can be used. Further, it is preferable not to use a wet paper strength enhancer.

In addition, when the used paper raw material is used as toilet paper, the same treatment as in the case of virgin type is performed.

<Embossed pattern>
It is preferable to provide an embossing pattern on the toilet paper in the toilet roll 1 of the present invention, and it is preferable to have a single embossing pattern 2. The 1-ply toilet paper may be embossed a plurality of times, but in this case as well, the single embossing pattern 2 is obtained. The embossed pattern refers to the shape of the unevenness formed by the embossing process.

FIG. 2 shows a photographed image of the recess 2R of the embossed pattern of the single embossed pattern 2 on the front surface side of the toilet paper in the toilet roll 1. In the toilet roll 1 according to the present invention, the front side of the toilet paper means the surface constituting the outside of the toilet roll 1, and the back side of the toilet paper is the inside of the toilet roll 1 which is the paper tube side. Means the faces that make up.

(Depth of embossed pattern)
FIG. 3 is a cross-sectional view showing a single embossed pattern 2 provided on the 1-ply toilet paper in the toilet roll 1. The upper part of FIG. 3 corresponds to the roll surface side, FIG. 3A shows a case where the depth D of the embossed pattern is deep, and FIG. 3B shows a case where the depth D of the embossed pattern is shallow. The paper thickness t2 of the toilet paper after the embossing treatment (this paper thickness reflects the distance between the non-embossed pattern portion on the front surface side of the toilet paper and the convex portion 2P of the embossed pattern on the back surface side) is the same. Is. However, even when the thickness t2 of the toilet paper is the same, the sheet is softer and has a better texture in FIG. 3A in which the embossed pattern is attached so that the depth D of the embossed pattern becomes deeper. It is considered that this is because in FIG. 3A, in which the unevenness of the embossed pattern is remarkable, the bulk of the base paper is higher (the density is lower), the deformation is more likely to occur, and the softness of the sheet is improved. Be done. Further, if the surface side of the toilet paper is smoothed without providing an embossed pattern, the surface is too smooth and the surface feels crisp, and the softness of the sheet is inferior.

Therefore, the depth D of the embossing pattern of the single embossing pattern 2 of the toilet paper in the toilet roll 1 of the present invention is preferably 0.01 mm or more and 0.35 mm or less, and 0.04 mm or more and 0.30 mm or less. Is more preferable, and 0.09 mm or more and 0.24 mm or less is further preferable.

By setting the depth D of the embossed pattern of the toilet paper in the toilet roll 1 of the present invention within the above numerical range, the roll density is better and the softness is superior to that of the two-ply laminated toilet roll 1. It can be a toilet roll 1.

If the recess 2R of the embossed pattern is provided on the surface side of the toilet paper where water easily adheres when using the warm water washing toilet seat, the recess 2R has a better tactile sensation than the convex portion 2P, so that the softness of the sheet is improved. do.

The depth D of the embossed pattern of the toilet paper in the toilet roll 1 of the present invention is obtained by measuring the height difference of the embossed pattern using a microscope.

As the microscope, the product name "One-shot 3D measurement macroscope VR-3100" manufactured by KEYENCE can be used. The product name "VR-H1A" can be used as the image observation / measurement / image analysis software of the microscope. The measurement is performed under the conditions of a magnification of 12 times and a visual field area of 24 mm × 18 mm. The measurement magnification and the visual field area may be appropriately changed depending on the size of the desired embossed pattern.

First, as shown in FIG. 4, the longest portion a of the peripheral edge fr of the embossed pattern is obtained. FIG. 5A shows the height profile on the XY plane by the microscope, and it can be seen that the height of the toilet paper surface is represented by shading. The dark-colored portion in FIG. 5 (a) shows an individual embossed pattern, and the longest portion a of one embossed pattern can be distinguished from FIG. 5 (a). By drawing the line segments AB crossing the longest portion a, the height (measurement cross-sectional curve) profile of the embossed pattern is obtained as shown in FIG. 5 (b). Here, since the convex portion (non-embossed pattern portion) and the concave portion of the embossed pattern can be seen from the shade of color of the XY plane image, the line segment AB so as to cross the portion where the convex portion and the concave portion are adjacent to each other. You just have to decide.

Here, the height profile in FIG. 5B is a (measured) cross-sectional curve T representing the unevenness of the sample surface of the actual toilet paper, but noise (fiber lumps or fibers on the surface of the toilet paper). It also contains a steep peak caused by a beard-like extension or a portion without fibers), and it is necessary to remove such a noise peak when calculating the height difference of the unevenness.

Therefore, as shown in FIG. 6, the "contour curve" U is calculated from the cross-sectional curve T of the height profile, and two inflection points P1 and P2 that are convex upward in the contour curve U are obtained. By finding the minimum value sandwiched between the inflection points P1 and P2, the minimum value Min of the depth is obtained. Further, the average value of the depth values of the inflection points P1 and P2 is defined as the maximum depth value Max.

In this way, the depth D of the embossed pattern = maximum value Max-minimum value Min. Further, the distance (length) of the inflection points P1 and P2 on the XY plane is defined as the length of the longest portion a. The "contour curve" is λc: 800 μm from the cross-sectional curve (however, λc is the “filter defining 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 component of the surface roughness of a shorter wavelength by a low region filter. If λc is set to be equal to or larger than the P1 spacing between adjacent embossed patterns (this is called embossing pitch), the peak may be recognized as noise, so λc is set to be less than the embossing pitch. For example, when the embossing pitch is 800 μm or less, for example, λc: 250 μm is set. For the spacing of P1 between adjacent embossed patterns, P1 and P2 are obtained in the same manner for the next embossed pattern connected to the left or right in FIG. 6, and two P1 when the adjacent embossed patterns are lined up with P1, P2 and P1. The interval between.

Similarly, in FIG. 5A, the depth D of the embossed pattern is measured for the longest portion b in the direction perpendicular to the longest portion a, and among the depths D of the embossed patterns of the longest portions a and b, The larger value is adopted as the depth D of the embossing pattern. The above measurement is performed for any 10 embossed patterns on the surface side of the toilet paper, and the average value thereof is adopted as the depth D of the final embossed pattern. However, as shown in FIG. 7, when the embossed pattern is connected in the flow direction (MD direction), the longest portion a becomes the same as the winding length, the height difference cannot be obtained, and the depth D of the recess is reduced. Cannot measure. Therefore, the line segments AB can be drawn so as to straddle the embossed pattern in the width W direction orthogonal to the direction in which the embossed patterns are connected (MD direction), and the depth D of the recess can be measured. Similarly, when the embossed pattern is connected in the width W direction (CD direction), the line segments AB are drawn so as to straddle the embossed pattern in the flow direction (MD direction), and the depth D of the recess is measured.

Further, when selecting any 10 embossing patterns in the measurement of the depth D of the embossing pattern, the winding of the toilet roll 1 is started from the end of the outer winding of the toilet roll 1 (the position where the toilet paper is started to be used). Measure at the part corresponding to 20% of the length. For example, when the winding length is 150 m, the measurement is performed at a portion of 150 m × 20% = 30 m from the end portion. If 20% of the winding length hits the perforation, measure the outer winding side of the perforation.

When measuring the depth D of the embossed pattern, the measurement surface is the surface side of the toilet paper.

(Area of embossed pattern)
For the area of each embossed pattern of the toilet paper in the toilet roll 1 of the present invention, the product (a × b) of the longest portion a and the longest portion b is obtained as the area S of the embossed pattern. For the longest portion a and the longest portion b, the values obtained by averaging the values of the individual a and b for the 10 embossed patterns on the front surface side of the toilet paper are used. As a method for measuring the area of the embossed pattern, the above-mentioned method for measuring the depth D of the embossed pattern can be used.

The area S of each embossed pattern of the single embossed pattern 2 of the toilet paper in the toilet roll 1 of the present invention is preferably 0.2 mm ² or more and 9.0 mm ² or less, and 1.0 mm ² or more and 7.0 mm ² or less. It is more preferably 1.8 mm ² or more and 5.0 mm ² or less. The area ratio of the embossed pattern (the ratio of the portion of the toilet paper having the embossed pattern) is preferably 3% or more and 60% or less, more preferably 7% or more and 45% or less, and 10%. It is more preferably 30% or less. When it is difficult to obtain the area ratio of the embossed pattern of the toilet paper, the area ratio of the convex portion of the embossed roll 111 can be used as the area ratio of the embossed pattern. By setting the area and the area ratio of the embossed pattern within the above numerical range, the cosmeticity and the winding density can be improved.

The shape of the embossed pattern is not particularly limited, such as a rectangle, a square, a round shape, an oval shape, or the like. Further, the winding diameter and the winding density can be adjusted by appropriately adjusting the size of the embossed pattern and the area ratio (number) of the embossed patterns shown above.

<Whiteness>
When the deinked pulp contains a fluorescent dye, the difference Δ between the whiteness value of the toilet paper (sheet) under the UV-in condition and the whiteness value under the UV-cut condition becomes large. Here, UV-in is a whiteness compliant with ISO 2470 when the sheet surface side is irradiated with a C light source (including ultraviolet light) defined by CIE (International Commission on Illumination). UV-cut is a whiteness compliant with ISO 2470 when a C light source is applied to the sheet surface side through a filter that cuts ultraviolet light having a wavelength of 420 nm or less. The difference Δ = (whiteness UV-in)-(whiteness UV-cut). The whiteness can be measured using a high-speed spectrophotometer CMS-35SPX manufactured by Murakami Color Technology Laboratory Co., Ltd. in accordance with ISO 2470.

In the toilet roll 1 of the present invention, the difference Δ between the whiteness UV-in and the whiteness UV-cut on the surface side of the toilet paper is preferably 0.0 points or more and 2.5 points or less, preferably 0.0 points. It is more preferably 1.5 points or more, more preferably 0.0 points or more and 1.0 points or less, and particularly preferably 0.0 points or more and 0.5 points or less.

<Basis weight>
The basis weight of the toilet paper in the toilet roll 1 of the present invention is preferably 15.0 g / m ² or more and 22.0 g / m ² or less, and 17.0 g / m ² or more and 21.0 g / m per ply. It is more preferably ² or less, and further preferably 18.0 g / m ² or more and 20.0 g / m ² or less.

<Paper thickness>
The paper thickness of the toilet paper in the toilet roll 1 of the present invention is preferably 0.40 mm / 10 sheets or more and 1.10 mm / 10 sheets or less, and 0.55 mm / 10 sheets or more and 1.00 mm / 10 sheets or less. It is more preferable, and it is more preferable that it is 0.70 mm / 10 sheets or more and 0.90 mm / 10 sheets or less.

By setting the basis weight and paper thickness per ply of toilet paper in the toilet roll 1 of the present invention within the above numerical ranges, the winding density and the roll density can be easily adjusted, and the strength is good. The toilet roll 1 can be made to have a good feeling of use and bulkiness.

<Specific volume>
The specific volume of the toilet paper in the toilet roll 1 of the present invention is expressed by the volume cm ³ per unit g, which is obtained by dividing the paper thickness per sheet by the basis weight per sheet.

The specific volume of the toilet paper in the toilet roll 1 of the present invention is preferably 2.8 cm ³ / g or more and 6.5 cm ³ / g or less, and is 3.1 cm ³ / g or more and 5.5 cm ³ / g or less. It is more preferable that it is 3.7 cm ³ / g or more and 4.8 cm ³ / g or less.

By setting the specific volume of the toilet paper in the toilet roll 1 of the present invention within the above numerical range, the softness and water absorption of the sheet are good, and the bulkiness of the embossing treatment is good. Can be done.

<Strength>
The strength of the 1-ply toilet paper in the toilet roll 1 of the present invention is DMDT (Dry Machine Direction Tensile strength), which is the longitudinal tensile strength during drying, and the lateral tensile strength, which is based on JIS P 8113. DCDT (Dry Cross Direction Sense strength). In the toilet roll 1 according to the present invention, the flow direction of the papermaking of the product is the vertical direction, and the direction perpendicular to the flow direction is the horizontal direction.

The DMDT of the 1-ply toilet paper in the toilet roll 1 of the present invention is preferably 2.5 N / 25 mm or more and 7.0 N / 25 mm or less, and preferably 3.0 N / 25 mm or more and 5.8 N / 25 mm or less. More preferably, it is 3.5 N / 25 mm or more and 4.5 N / 25 mm or less. Further, the DCDT of the 1-ply toilet paper in the toilet roll 1 of the present invention is preferably 0.7 N / 25 mm or more and 2.2 N / 25 mm or less, and 0.8 N / 25 mm or more and 1.8 N / 25 mm or less. More preferably, it is more preferably 1.0 N / 25 mm or more and more preferably 1.5 N / 25 mm or less. The tensile strength is measured under the condition of a tensile speed of 300 mm / min. Further, the tensile strength can be adjusted by a known method.

By setting the DMDT and DCDT of the toilet paper in the toilet roll 1 of the present invention within the above numerical ranges, the toilet roll 1 having good strength and softness can be obtained.

<Water absorption>
The water absorption of the toilet paper in the toilet roll 1 of the present invention is measured based on the old JIS S 3104. However, the dropping amount is 0.01 ml instead of 0.1 ml.

The water absorption of the 1-ply toilet paper in the toilet roll 1 of the present invention is preferably 7.0 seconds or less, more preferably 5.0 seconds or less, and further preferably 3.0 seconds or less. preferable. By setting the value within the above numerical range, the toilet roll 1 having good water absorption and water absorption can be obtained. When dropping water, drop it on the surface side of the toilet paper.

<Easy to unravel>
The ease of loosening of the toilet paper in the toilet roll 1 of the present invention is measured based on JIS P 4501.

The ease of unraveling the 1-ply toilet paper in the toilet roll 1 of the present invention is preferably 8 seconds or more and 60 seconds or less, more preferably 15 seconds or more and 50 seconds or less, and 20 seconds or more and 40 seconds or less. It is more preferable to have. By setting the value within the above numerical range, the toilet roll 1 can be easily loosened, hydrolyzable, and has good water resistance when the toilet paper gets wet with water when using a warm water washing toilet seat.

[Manufacturing method of toilet roll]
The details of the toilet roll 1 and the method for manufacturing the toilet paper of the present invention will be described.

The toilet roll 1 and the toilet paper can be manufactured in the order of (i) papermaking and creping, (ii) calendar processing by a machine winder, (iii) embossing and roll winding processing, for example, as follows.

(I) Papermaking and creping First, the web is made from the above-mentioned paper material on the wire part of a known paper machine and transferred to the felt of the press part. Examples of the wire part method include a round net type, a long net (Ford linear) type, a suction breast type, a short net type, a twin wire type, and a crescent former type.

Then, the web is continuously dehydrated by a dehydration method such as dehydration by mechanically compressing the web with a suction pressure roll, a pressure roll without suction, a press roll, or the like, or dehydration by aeration drying with hot air. Suction pressure rolls or non-suction pressure rolls are also used as a means of moving the web from the press part to the Yankee dryer.

The web transferred to the Yankee dryer is dried by the Yankee dryer and the Yankee dryer hood, then scraped by a creping doctor and wound up by a reel part.

Creping (creating wrinkles called crepes) is the mechanical compression of paper in the vertical direction (the sheet running direction on the paper machine). Then, when manufacturing the web of toilet paper, the web on the Yankee dryer is peeled off by the creping doctor and wound up on the reel part, but the speed difference between the Yankee dryer and the reel part (speed of the reel part ≤ speed of the Yankee dryer). ) To form a crepe (wrinkle) at the creping doctor.

The quality required for toilet paper, that is, bulk (bulk feeling), softness, water absorption, surface smoothness, aesthetics (crepe shape), etc., depends on the above speed difference. Although it depends on the conditions such as the speed difference, the basis weight of the web on the reel after creping is approximately 16 g / m ² or more and 24 g / m ² or less, which is heavier than the basis weight of the web on the Yankee dryer before creping. The basis weight is preferably 18 g / m ² or more and 23 g / m ² or less, and more preferably 19 g / m ² or more and 22 g / m ² or less. If it exceeds the above range, the strength may become high and the paper may become stiff, or the winding density or roll density may become too large. May be inferior.

Here, the crepe rate based on the speed difference between the Yankee dryer and the reel is defined by the following equation.
Crepe rate (%) = 100 x (Yankee dryer speed (m / min) -reel speed (m / min)) ÷ reel speed (m / min)

The quality and operability are largely determined by the creping conditions, and the operating conditions that optimize the creping conditions are important for those skilled in the art. In the present invention, the crepe ratio when producing toilet paper is preferably 10% or more and 50% or less, more preferably 15% or more and 40% or less, and further preferably 20% or more and 35% or less. preferable.

(Ii) Calendar processing by machine winder FIG. 8 shows an example of machine winder 100.

As described above, the reel 11 wound up by the reel part after crepe is set in the machine winder 100, calendar-processed, and becomes the original roll 12. It is also possible to perform calendar processing with the on-machine calendar.

The thickness of the toilet paper before embossing (after calendar processing) is preferably 0.50 mm / 10 sheets or more and 1.50 mm / 10 sheets or less, and 0.60 mm / 10 sheets or more and 1.30 mm / 10 sheets or less. It is more preferably 0.70 mm / 10 sheets or more, and further preferably 1.10 mm / 10 sheets or less. The specific volume of the toilet paper in the raw roll 12 before the embossing treatment (after the calendar treatment) is preferably 3.2 cm ³ / g or more and 6.3 cm ³ / g or less, preferably 3.5 cm ³ / g or more. It is more preferably 5.8 cm ³ / g or less, and further preferably 3.8 cm ³ / g or more and 5.3 cm ³ / g or less.

The paper thickness of the toilet paper before the embossing treatment is the paper thickness of the original roll 12 after the calendering treatment in FIG. 8, 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 measured load of 3.7 kPa, it does not accurately reflect the paper thickness t1 in FIG.

The first-stack calendar machine 101 and the second-stack calendar machine 102 are preferably composed of two metal rolls, respectively, but one of the two rolls is an elastic roll so that soft calendar processing can be performed. You may do it.

The linear pressure of the calendar is preferably 2.5 kgf / cm or more and 7.5 kgf / cm or less, and more preferably 3.0 kgf / cm or more and 7.0 kgf / cm or less. By setting the wire thickness within the above numerical range, the softness and the winding diameter DR of the roll can be improved. Further, it is preferable that the linear pressure is higher in the second stack than in the first stack.

The draw can be adjusted as appropriate during calendar processing. The draw between the reel 11 and the original roll 12 after the calendar processing is preferably 100% or more and 110% or less, and more preferably 102% or more and 108% or less.

The basis weight of the web of the raw roll 12 after the calendar processing and before the embossing treatment is preferably 15.5 g / m ² or more and 23.5 g / m ² or less, and 17.5 g / m ² or more per ply. It is more preferably 22.5 g / m ² or less, and further preferably 18.5 g / m ² or more and 21.5 g / m ² or less. In the roll winding process described later, the web is slightly stretched and the basis weight is also low, so it is preferable to set the basis weight slightly higher than the target basis weight of the toilet roll 1 in the final form.

In order to increase the depth D of the embossed pattern, it is necessary to reduce the paper thickness t1 per sheet to make the unevenness noticeable. Therefore, the softness of the sheet is caused by the strong calendar processing of the base paper. Can be improved. Since the web is slightly stretched in the roll winding process, the paper thickness becomes low as well as the basis weight before and after winding, but the target paper thickness of the toilet roll 1 in the final form can be adjusted by the embossing process. Also, depending on the embossing pattern, the paper thickness may become lower after the embossing process. In that case, adjust the base paper and calendar as appropriate so that the target paper thickness and winding density of the toilet roll are reached. ..

(Iii) Embossing and roll winding processing FIG. 9 shows an example of the roll winding processing machine 110.

The original roll 12 after the calendering process is set in the roll winding processing machine 110, is single-embossed by the embossing unit (embossed roll 111), and then is subjected to the single embossing process by the winding mechanism 113. It is taken up by. After that, the base paper roll 13 is cut into a predetermined width (114 mm or the like) to become a toilet roll 1. It is preferable that the raw roll 12 used in the roll winding processing machine is fed out so that the front surface side of the toilet paper is the Yankee surface.

The roll take-up processing machine 110 is roughly classified into two types, a surface type and a center type. The surface method is a method of winding while supporting the roll to be wound from the outside by another plurality of drive rolls, and the wound toilet roll 1 has an easy control of the winding diameter and a higher production speed. The center method is a method of winding by driving a shaft passed through the center of the winding roll, and the wound toilet roll 1 becomes a relatively soft product and is suitable for a delicately embossed product. In the present invention, any method can be used for winding, but the surface method is preferable. According to the surface method, the winding diameter and winding density of the roll can be adjusted relatively easily by the winding strength of the roll.

The machine winder 100 may be incorporated in the roll winding processing machine 110, and the calendar processing and the embossing processing may be performed in this order by the roll winding processing machine 110.

The single embossed pattern 2 is formed by pressing the convex portion of the embossed pattern of the embossed roll 111 against the surface of the original roll 12 on the surface side (Yankee surface side). As a result, an embossing pattern (single embossing pattern 2) is formed in which the concave portion 2R appears on the surface (the surface on the front surface side) of the toilet paper on which the embossing roll 111 of the toilet paper is pressed, and the convex portion 2P appears on the back surface. The material of the embossed roll is preferably metal.

The depth D of the embossed pattern can be controlled by appropriately adjusting the nip width of the rubber roll 112 facing the embossed roll 111. For example, the depth D of the embossing pattern can be adjusted by narrowing the nip width when the unevenness of the embossing roll 111 is deep and widening the nip width when the unevenness of the embossing roll 111 is shallow. Further, the strength of winding the roll can be adjusted so as to secure the depth D of the embossed pattern. For example, if the depth of the embossed pattern is increased, the embossed pattern is likely to be crushed when the roll is wound. Therefore, the depth D of the embossed pattern can be adjusted by lowering the strength of winding the roll. Specifically, in the roll take-up processing machine 110, when the roll take-up mechanism 113 winds the base paper roll 13 onto a wide base paper roll 13, the pressing force of the rider roll 114 for pressing the base paper roll 13 from the outer peripheral side to sequentially wind the sheet. Can be adjusted by setting to a predetermined range.

The nip width varies depending on the characteristics of the roll, but is preferably 20 mm or more and 50 mm or less, more preferably 25 mm or more and 45 mm or less, and further preferably 30 mm or more and 40 mm or less. By setting the nip width within the above numerical range, the difference between the front and back of the tactile sensation between the concave portion 2R of the embossed pattern on the front surface side and the convex portion 2P of the embossed pattern on the back surface side is good, and the winding density and the softness of the sheet are good. It can also be good.

The nip width can be measured using carbon paper. As a measuring method, first, the nip of the embossed roll 111 is released, and carbon paper and general copy paper are placed on top of each other and set. Next, the emboss roll 111 is niped. After that, let the nip escape and remove the carbon paper and copy paper. Since the color of the carbon paper in the portion where the nip is applied by the emboss roll 111 is transferred to the copy paper, the nip width can be measured.

The roll winding processing machine 110 can simultaneously perform printing, embossing pattern imparting, perforation processing, tail sealing, and cutting of a predetermined width (114 mm, etc.), and can manufacture the toilet roll 1. Further, after that, the film packaging process can be performed to manufacture the package of the toilet roll 1.

The means for ensuring the softness of the toilet paper is not limited to the embossed pattern as long as it imparts unevenness to the surface, and for example, an uneven fabric may be used to make the web uneven at the time of papermaking. In this case, the depth of the unevenness may be in a range corresponding to the depth D of the embossing pattern described later.

The content of the pulp composition was (% by mass) NBKP 5%, LBKP 60%, and used paper derived from milk carton 35%, and no deinked pulp was contained. The toilet paper and toilet roll shown in 2 were manufactured.

The following evaluations were made.

Basis weight: Measured based on JIS P 8124 and converted per sheet.

Paper thickness: Measured using a thickness gauge (dial thickness gauge "PEACOCK" manufactured by Ozaki Seisakusho). The measurement conditions were a measuring load of 3.7 kPa, a stylus diameter of 30 mm, a sample was placed between the stylus and the measuring table, and the gauge when the stylus was lowered at a speed of 1 mm or less per second was read. The measurement was repeated 10 times using 10 sheets of toilet paper stacked as a sample, and the measurement results were averaged. The paper thickness can be measured in the same manner for the web before calender processing and the web after calender processing.

Specific volume: The paper thickness per sheet is divided by the basis weight per sheet and expressed as the volume cm ³ per unit g.

Based on the vertical tensile strength DMDT during drying and the lateral tensile strength DCDT during drying: JIS P 8113, the maximum load until breakage was measured for toilet paper (1 ply) in units of N / 25 mm. The tensile strength is measured under the condition of a tensile speed of 300 mm / min.

Roll diameter DR: Measured using a dial meter rule manufactured by Muratec KDS Co., Ltd. In the measurement, 10 rolls were measured and the measurement results were averaged.

Outer diameter of core: Measured using a dial meter rule manufactured by Muratec KDS Co., Ltd. In the measurement, 10 cores were measured and the measurement results were averaged.

Volume length: The length of 10 sheets was actually measured for the sheets between the perforations of the toilet roll. After that, the number of sheets of the roll was actually measured, and the winding length 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 660 sheets, it is 2.275 m × (660/10) = 150 m. If there are no perforations, it can be actually measured.

The roll density, roll density, and embossing pattern depth were measured by the above methods. In Table 2, when the depth of the embossed pattern is less than 0.01 mm, it is regarded as a hyphen.

The paper thickness of the toilet paper after the embossing shown in Tables 1 and 2 corresponds to the paper thickness t2 in FIG. 3, but since it is a value measured with a measured load of 3.7 kPa, the paper thickness t2 can be accurately calculated. It is not a reflection.

Further, the depth of the embossed pattern is measured in the generated state in which the embossed pattern is not compressed. Therefore, the depth of the embossed pattern is significantly larger than the value calculated from the paper thicknesses t1 and t2 (this value is the value obtained by compressing the embossed pattern with the measured load of 3.7 kPa).

Sensory evaluation was performed by 20 monitors. The evaluation standard was a maximum of 5 points. It is good if the evaluation standard is 3 points or more.

The measurement of basis weight, tensile strength, paper thickness, specific volume, core outer diameter, winding length, winding diameter, winding density, roll density, roll mass, roll softness and embossed pattern depth is JIS P. This was performed after maintaining the equilibrium state under the temperature and humidity conditions (23 ± 1 ° C., 50 ± 2% RH) specified in 8111.

The obtained results are shown in Tables 1 and 2.

As is clear from Tables 1 and 2, in the case of each embodiment in which the winding length, winding diameter, winding density, and roll density of the toilet roll are within the predetermined numerical ranges, the sheet and roll are soft without reducing the basis weight. It was possible to increase the winding length per roll while improving both.

On the other hand, although the softness of the sheet was excellent by giving an embossed pattern of an appropriate depth, in the case of Comparative Example 1 in which the winding length was less than 105 m, the winding diameter was less than 107 mm, and the roll replacement frequency increased. rice field.

Further, although the softness of the sheet was excellent by giving an embossed pattern of an appropriate depth, in the case of Comparative Example 2 in which the winding length exceeded 210 m, the winding diameter exceeded 140 mm and the roll diameter became large, so that the toilet was used. It became difficult to fit in the paper holder.

Further, in the case of Comparative Example 3 in which the depth D of the embossed pattern is less than 0.01 mm and the roll density exceeds 0.37 g / cm ³ , the degree of unevenness of the embossed pattern becomes small and the bulk becomes low (high density). The softness of the sheet and roll was inferior.

In the case of Comparative Example 4 in which the depth D of the embossed pattern exceeds 0.35 mm and the roll density is less than 0.21 g / cm ³ , the unevenness of the embossed pattern becomes too remarkable and the bulk becomes too high (the density becomes low). The roll diameter of the toilet roll exceeded 140 mm, and the roll diameter became large, making it difficult to fit in the toilet paper holder.

In the case of Comparative Example 5 in which the toilet paper was wound too strongly (hardly) with a roll winding machine and the roll density exceeded 0.37 g / cm ³ , the winding diameter was less than 107 mm, and the softness of the roll was inferior.

In the case of Comparative Example 6 in which the toilet paper is wound too weakly (softly) with a roll winding machine and the roll density is less than 0.21 g / cm ³ , the winding diameter of the toilet roll exceeds 140 mm and the roll diameter becomes large. It became difficult to fit in the paper holder.

Regarding Comparative Example 6, in the case of Comparative Example 7 in which the winding density and the roll density were within the predetermined numerical ranges in addition to the winding diameter, the fit in the toilet paper holder was good, but the winding length was less than 105 mm. The frequency of roll replacement has increased.

Regarding Comparative Example 3, in the case of Comparative Example 8 in which the roll density was within a predetermined numerical range in addition to the winding density, the softness of the roll was good, but the depth D of the embossed pattern was less than 0.01 mm. The softness of the sheet was inferior because it remained.

When the commercially available products 1 and 2 were evaluated in the same manner, the winding length was less than 105 m in each case, and the frequency of roll replacement increased.

1 Toilet roll 11 Reel 12 Original roll 13 Base paper roll 100 Machine winder 101 1st stack calendar machine 102 2nd stack calendar machine 110 Roll take-up machine 111 Emboss roll 112 Rubber roll 113 Winding mechanism 114 Rider roll 2 Emboss pattern (Single embossed pattern)
2R concave part 2P convex part

Claims (4)

It is a non-chemically applied toilet roll made by winding 1-ply toilet paper into a roll.
An embossed pattern is provided on the toilet paper.
The winding length of the toilet roll is 136 m or more and 185 m or less, the winding diameter is 114 mm or more and 132 mm or less, the winding density is 1.24 m / cm ² or more and 1.67 m / cm ² or less, and the roll density is 0.24 . g / cm ³ or more and 0.32 g / cm ³ or less,
A toilet roll having a depth of the embossed pattern of 0.06 mm or more and 0.27 mm or less. The toilet roll according to claim 1, wherein the toilet paper contains 40% by mass or more and 100% by mass or less of kraft pulp. The toilet roll according to claim 1 or 2, wherein the toilet paper contains 0% by mass or more and 60% by mass or less of used paper pulp derived from a milk carton. A whiteness UV-in compliant with ISO 2470 when the surface side of the toilet paper is irradiated with a C light source specified by the CIE (International Commission on Illumination) and a filter that cuts ultraviolet light with a wavelength of 420 nm or less are used. Any of claims 1 to 3 in which the difference Δ from the ISO 2470-compliant whiteness UV-cut when the C light source is applied to the surface side of the toilet paper is 0.0 points or more and 2.5 points or less. Toilet rolls listed in.

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