JP7387541B2 - toilet roll products - Google Patents

Description

The present invention relates to toilet roll products.

Toilet roll products are required to have a certain degree of strength and bulk. Furthermore, in order to facilitate transportation and storage, it is required to increase the winding length and reduce the winding diameter. For this reason, the density of toilet roll products can often be increased without reducing the basis weight of the toilet paper. On the other hand, embossed patterns are applied to toilet roll products to improve the tactile sensation and cosmetic appearance during use. However, increasing the density of toilet roll products can cause the embossed pattern to collapse due to the increased pressure exerted on the toilet paper. By adjusting the area ratio of the embossed pattern within a predetermined range, the toilet roll of Patent Document 1 maintains good tactile feel and cosmetic appearance during use, and increases the roll diameter while increasing the roll length of the toilet roll. Avoiding getting bigger.

JP2019-97765A

In order to further improve the usability and cosmetic properties, there is a need to further reduce the difference in texture between the front and back surfaces of toilet roll products. A tissue softness analyzer is known as a device for measuring the surface properties of tissue. However, the tissue softness analyzer may not be able to sufficiently measure the surface properties of toilet paper having an embossed pattern. That is, the correlation between the measurement results by the tissue softness analyzer and the sensory evaluation regarding the difference between the front and back surfaces may be low. Until now, there was no device that could properly evaluate the surface properties of toilet paper. Furthermore, in order to further improve the usability and cosmetic appearance, there is a need to reduce the difference between the front and back sides, and at the same time, to further reduce the possibility that the embossed pattern of the toilet paper will collapse.

The present disclosure has been made in view of the above-mentioned problems, and has appropriate strength and bulk, has a long winding length, has good tactile sensation and cosmetic appearance during use, and is portable and saves storage. To provide a toilet roll product which has excellent space properties, has a small difference between the front and back sides of the toilet roll product, and has an excellent shape retention property of an embossed pattern.

In order to achieve the above object, the toilet roll product of the present disclosure is a toilet roll product obtained by winding up a 2-ply toilet paper having an embossed pattern that is a single embossment into a roll, and the toilet roll product has a tsubo per 1 ply of the toilet paper. The amount is 11 g/m ² or more and 19 g/m ² or less, the winding length is 63 m or more and 128 m or less, the winding diameter is 103 mm or more and 151 mm or less, and the area ratio of the embossed pattern is 30% or more and 45% or less, or 55% or more and 70% or less, and the frequency is 1Hz among the vibration stimulation values calculated based on the vibration characteristics of the toilet paper of 4ply measured using a vibration measurement device and the value of the lowest vibration detection threshold approximation line. The first vibration stimulation value in the first region which is 3Hz or more is 300V/s or more and 800V/s or less, and the second vibration in the second region whose frequency is 3Hz or more and 40Hz or less among the vibration stimulation values. The stimulation value is 8500 V/s or more and 11000 V/s or less, and among the vibration stimulation values, the third vibration stimulation value in a third region whose frequency is greater than 40 Hz and 1000 Hz or less is 8000 V/s or more and 11000 V/s or less. and the difference between the first vibration stimulation value for the front surface of the toilet paper and the first vibration stimulation value for the back surface of the toilet paper is −400 V/s or more and 400 V/s or less, and The difference between the second vibration stimulation value for the front surface of the toilet paper and the second vibration stimulation value for the back surface of the toilet paper is −3000 V/s or more and 3000 V/s or less, and the difference is between the third vibration stimulation value for the front surface of the toilet paper and The difference from the third vibration stimulation value regarding the back side of the toilet paper is −2500 V/s or more and 2500 V/s or less.

By having the above-mentioned basis weight, roll length, and roll diameter, and by having the toilet paper have a single-embossed embossed pattern, the toilet roll product has appropriate strength and bulk, has a long roll length, and is easy to use. It has good texture and cosmetic appearance, and is excellent in portability and space saving during storage. Further, when the area ratio of the embossed pattern is 30% or more or 70% or less, the difference between the front and back surfaces becomes small. When the area ratio of the embossed pattern is 45% or less or 55% or more, the embossed pattern becomes difficult to collapse. More specifically, the edges of the embossed portion are easily maintained, making it difficult for the embossed portion to collapse. Furthermore, since the first vibration stimulation value (I _SAI ), the second vibration stimulation value ( _IFAI ), and the third vibration stimulation value (I _FAII ) are each within the above-mentioned ranges, the difference between the front and back surfaces becomes smaller, and The embossed pattern is less likely to collapse. Therefore, the toilet roll product of the present disclosure has appropriate strength and bulk, has a long roll length, has good tactile feel and cosmetic appearance during use, is excellent in portability and space saving during storage, and has both front and back sides. The difference is small and the shape retention of the embossed pattern is excellent.

In the toilet roll product of the present disclosure, the depth of the embossed pattern is preferably 0.01 mm or more and 0.30 mm or less.

As a result, the toilet roll product of the present disclosure can further improve the tactile feel and cosmetic properties during use, and can further reduce the difference between the front and back sides.

In the toilet roll product of the present disclosure, the embossed pattern includes a plurality of embossed portions that are concave portions, and a straight line passing through the center of gravity of one of the embossed portions and the center of gravity of the embossed portion closest to the embossed portion is a first straight line, When a second straight line is a straight line perpendicular to the first straight line, the angle between the second straight line and a reference line parallel to the flow direction is larger than the angle between the reference line and the first straight line. It is preferable.

Thereby, the toilet roll product of the present disclosure can improve the feel on the skin and the fit on the fingertips. According to the toilet roll product of the present disclosure, the tactile sensation during use is improved.

In the toilet roll product of the present disclosure, the angle between the reference line and the first straight line is preferably 0° or more and 3° or less.

Thereby, the toilet roll product of the present disclosure can further improve embossed shape retention.

In the toilet roll product of the present disclosure, the embossed pattern includes an auxiliary embossed part that is a recess that is disposed between two adjacent embossed parts in a direction parallel to the second straight line and connected to the embossed part, It is preferable that a comma shape is drawn by one of the embossed portions and one of the auxiliary embossed portions.

When forming an embossed pattern by embossing, the toilet paper is sandwiched between a rubber roll and an embossed roll having convex portions. By providing the toilet paper with the auxiliary embossing portion, the convex portion of the embossing roll comes into uniform contact with the rubber roll. Therefore, the modified toilet paper can slow down the deterioration rate of the rubber roll used for embossing.

In the toilet roll product of the present disclosure, the thickness of the toilet paper is preferably 0.45 mm/10 ply or more and 1.20 mm/10 ply or less.

As a result, the toilet roll product of the present disclosure can be easily wound into a roll while having the above-mentioned basis weight, roll length, and roll diameter.

The toilet roll product of the present disclosure has a dry longitudinal strength of 280 gf/25 mm or more and 550 gf/25 mm or less, which is the tensile strength in the longitudinal direction when dry, and a dry lateral strength of 80 gf, which is the tensile strength in the lateral direction when dry. It is preferable that it is 210gf/25mm or more and 210gf/25mm or less.

As a result, the toilet roll product of the present disclosure can be difficult to tear and have appropriate softness.

The toilet roll product of the present disclosure has appropriate strength and bulk, has a long roll length, has a good feel and cosmetic appearance during use, is excellent in portability and space saving during storage, and is a toilet roll product. The difference between the front and back sides is small and the embossed pattern has excellent shape retention.

FIG. 1 is a perspective view of the toilet roll product of this embodiment. FIG. 2 is a plan view of the embossed pattern of this embodiment. FIG. 3 is a perspective view of the vibration measuring device of this embodiment. FIG. 4 is a diagram showing the performance of the friction feel tester. FIG. 5 is an exploded view of the fixture. FIG. 6 is an exploded view of the sensor unit. FIG. 7 is a diagram showing the performance of the sensor. FIG. 8 is a graph showing vibration waveforms measured by the vibration measuring device. FIG. 9 is a graph showing the calculated amplitude spectrum. FIG. 10 is a diagram showing a vibration detection threshold curve. FIG. 11 is a diagram showing a minimum vibration detection threshold approximation line. FIG. 12 is a graph showing the amplitude spectrum and the lowest vibration detection threshold approximation line. FIG. 13 is a diagram showing an example of the calculated first vibration stimulation value, second vibration stimulation value, and third vibration stimulation value when the vibration on the surface of the sample is measured. FIG. 14 is a diagram showing an example of the calculated first vibration stimulation value, second vibration stimulation value, and third vibration stimulation value when the vibration on the surface of the sample is measured. FIG. 15 is a plan view of a modified emboss pattern.

Hereinafter, the present invention will be explained in detail with reference to the drawings. Note that the present invention is not limited to the modes for carrying out the present invention (hereinafter referred to as embodiments). Furthermore, the constituent elements in the embodiments below include those that can be easily imagined by those skilled in the art, those that are substantially the same, and those that are within the so-called equivalent range. Furthermore, the components disclosed in the embodiments below can be combined as appropriate.

(Embodiment)
FIG. 1 is a perspective view of the toilet roll product of this embodiment. FIG. 2 is a plan view of the embossed pattern of this embodiment. As shown in FIG. 1, the toilet roll product 60 of this embodiment is a product obtained by winding up a 2-ply toilet paper 70 into a roll shape. The roll length of the toilet roll product 60 is 63 m or more and 128 m or less. The roll length is the total length of the rolled up toilet paper 70. The winding length is also called the winding length. The roll diameter DR of the toilet roll product 60 is 103 mm or more and 151 mm or less. The winding diameter DR is also called the roll outer diameter. When the roll diameter DR is within the above range, the toilet roll product 60 can be easily accommodated in the holder.

The basis weight per ply of the toilet paper 70 is 11 g/m ² or more and 19 g/m ² or less. More preferably, the basis weight per ply of the toilet paper 70 is 12.5 g/m ² or more and 17.5 g/m ² or less. The thickness of the toilet paper 70 is preferably 0.45 mm/10 ply or more and 1.20 mm/10 ply or less. More preferably, the thickness of the toilet paper 70 is 0.60 mm/10 ply or more and 1.10 mm/10 ply or less. When the basis weight and thickness are within the ranges described above, the toilet paper 70 has appropriate strength and bulk.

The dry machine direction tensile strength (DMDT), which is the longitudinal tensile strength of the toilet paper 70 when drying, is preferably 280 gf/25 mm or more and 550 gf/25 mm or less. More preferably, the dry longitudinal strength of the toilet paper 70 is 330 gf/25 mm or more and 480 gf/25 mm or less. The longitudinal direction is the direction along the flow direction of the paper machine. The dry cross direction tensile strength (DCDT), which is the tensile strength in the lateral direction when the toilet paper 70 is dry, is preferably 80 gf/25 mm or more and 210 gf/25 mm or less. More preferably, the dry lateral strength of the toilet paper 70 is 110 gf/25 mm or more and 190 gf/25 mm or less. The transverse direction is the direction perpendicular to the flow direction of the paper machine. Dry longitudinal strength and dry transverse strength are measured based on JIS P8113.

In the following description, the surface of the toilet paper 70 facing outward in the radial direction of the toilet roll product 60 is referred to as the surface. The surface of the toilet paper 70 that faces inward in the radial direction of the toilet roll product 60 is referred to as the back surface. The flow direction of the toilet roll product 60 is described as flow direction DM. The flow direction DM is the direction in which the toilet paper 70 is rolled up, and is the longitudinal direction of the toilet paper 70. The width direction of the toilet roll product 60 is described as width direction DW. The width direction DW is a direction perpendicular to both the thickness direction and flow direction DM of the toilet paper 70.

As shown in FIG. 2, the toilet paper 70 has an embossed pattern 80. The embossed pattern 80 is formed by embossing. The emboss pattern 80 is a so-called single emboss. An embossed pattern 80 is formed by pressing a convex die from one side of the 2-ply stacked toilet paper 70. Since the embossed pattern 80 is formed on the 2-ply toilet paper 70 at the same time, the embossed pattern 80 is less likely to collapse. The depth of the embossed pattern 80 is preferably 0.01 mm or more and 0.30 mm or less. More preferably, the depth of the embossed pattern 80 is 0.03 mm or more and 0.25 mm or less.

The embossed pattern 80 includes a plurality of embossed portions 81 that are recessed portions. The embossed portion 81 has a substantially oval shape. A straight line passing through the center of gravity of one embossed portion 81 (embossed portion 81a) and the center of gravity of the embossed portion 81 (embossed portion 81b) closest to the embossed portion 81 (embossed portion 81a) is defined as a first straight line B1. In a plane parallel to the surface of the toilet paper 70, a straight line perpendicular to the first straight line B1 is defined as a second straight line B2. In this case, the angle γ between the first reference line A1 parallel to the flow direction DM and the second straight line B2 is larger than the angle α between the first reference line A1 and the first straight line B1. Hereinafter, a direction parallel to the first straight line B1 will be referred to as a first direction. A direction parallel to the second straight line B2 is referred to as a second direction. In other words, the plurality of embossed portions 81 are arranged in a grid pattern. The center of gravity of the embossed portion 81 is located at the intersection of a lattice formed by a straight line parallel to the first direction D1 and a straight line parallel to the second direction D2.

As shown in FIG. 2, a distance G2 between two adjacent embossed portions 81 in the second direction D2 is larger than a distance G1 between two adjacent embossed portions 81 in the first direction D1. The angle γ between the first reference line A1 parallel to the flow direction DM and the second straight line B2 is larger than the angle α between the first reference line A1 and the first straight line B1. The angle α is 0° or more and 3° or less. Therefore, the angle β between the second reference line A2 parallel to the width direction DW and the second straight line B2 is also 0° or more and 3° or less. The angle γ is 87° or more and 90° or less.

The area ratio of the embossed pattern 80 is 30% or more and 45% or less, or 55% or more and 70% or less. The area ratio of the embossed pattern 80 is the ratio that the embossed portion 81 occupies with respect to the unit area of the surface of the toilet paper 70. If the sum of the areas of all the embossed parts 81 in the unit length toilet paper 70 is S1, and the area of the unit length toilet paper 70 is S2, the area ratio is calculated as (S1/S2) x 100. .

For example, when the area ratio of the embossed pattern 80 is 30%, the ratio of the area occupied by the embossed part 81 to the surface area of the toilet paper 70 of unit length is 30%, and the area excluding the embossed part 81 is The area ratio is 70%. On the other hand, if we pay attention to the back surface of the toilet paper 70, of the area of the back surface of the toilet paper 70 of unit length, the proportion of the area occupied by the convex portion formed on the opposite side of the embossed portion 81 is 30%. The area ratio of the part excluding the part is 70%.

For example, when the area ratio of the embossed pattern 80 is 70%, the embossed portion 81 accounts for 70% of the surface area of the toilet paper 70 of unit length, and the area excluding the embossed portion 81 is The area ratio is 30%. On the other hand, paying attention to the back surface of the toilet paper 70, of the area of the back surface of the toilet paper 70 of unit length, the ratio of the area occupied by the convex portion formed on the opposite side of the embossed portion 81 is 70%. The area ratio of the part excluding the part is 30%. The toilet roll product 60 in which the area ratio of the embossed pattern 80 is X% and the toilet roll product 60 in which the area ratio of the embossed pattern 80 is (100-X)% have substantially the same quality.

Note that the arrangement of the plurality of embossed portions 81 in the embossed pattern 80 is not limited to the arrangement described above. Further, the shape of the embossed portion 81 does not have to be substantially elliptical, but may be circular, oval, polygonal, or the like.

Regarding the front and back sides of the 4-ply toilet paper 70, the first vibration stimulation value (hereinafter referred to as _ISAI ) is 300 V/s or more and 800 V/s or less. The difference between the I _SAI on the front side of the 4ply toilet paper 70 and the I _SAI on the back side is -400 V/s or more and 400 V/s or less. In other words, for _ISAI , the absolute value of the difference between the front and back surfaces is 400 V/s or less. _ISAI is a vibration stimulation value in a first region where the frequency is 1 Hz or more and 3 Hz or less. The surface of the 4ply toilet paper 70 is one of the two outermost surfaces of the eight surfaces of the toilet paper 70. The back side of the 4-ply toilet paper 70 is the other of the two outermost sides of the eight sides of the toilet paper 70.

Regarding the front and back surfaces of the 4-ply toilet paper 70, the second vibration stimulation value (hereinafter referred to as I _FAI ) is 8500 V/s or more and 11000 V/s or less. The difference between the I _FAI on the front side of the 4ply toilet paper 70 and the I _FAI on the back side is −3000 V/s or more and 3000 V/s or less. In other words, for I _FAI , the absolute value of the difference between the front and back surfaces is 3000 V/s or less. I _FAI is a vibration stimulation value in a second region where the frequency is greater than 3 Hz and less than 40 Hz.

Regarding the front and back surfaces of the 4-ply toilet paper 70, the third vibration stimulation value (hereinafter referred to as _IFAII ) is 8000 V/s or more and 11000 V/s or less. The difference between I _FAII on the front side of the 4ply toilet paper 70 and I _FAII on the back side is −2500 V/s or more and 2500 V/s or less. In other words, for _IFAII , the absolute value of the difference between the front and back surfaces is 2500 V/s or less. I _FAII is a vibration stimulation value in the third region where the frequency is greater than 40 Hz and less than 1000 Hz.

I _SAI , I _FAI , and I _FAII are vibration stimulation values calculated based on the vibration characteristics of the 4-ply toilet paper 70 measured using the vibration measurement device 10 described later and the value of the lowest vibration detection threshold approximation line. be. The 4-ply toilet paper 70 is made by laminating four sheets of 1-ply toilet paper 70 in the same direction. Note that the 4-ply toilet paper 70 may be one in which four sheets are overlapped by being folded.

Specifically, I _SAI , I _FAI , and I _FAII are calculated by the method described below. I _SAI , I _FAI , and I _FAII are calculated through a vibration measurement step, an amplitude spectrum calculation step, and a vibration stimulus value calculation step. The vibration measurement step is a step of measuring vibration information when the toilet paper 70 moves using a vibration measurement device 10 that includes a contact 51 in contact with the toilet paper 70 and a sensor 59 for detecting vibration. The amplitude spectrum calculation step is a step of calculating an amplitude spectrum for each frequency based on the vibration information of the toilet paper 70. The vibration stimulus value calculation step is a step of calculating I _SAI , I _FAI , and I _FAII based on the amplitude spectrum and the value of the lowest vibration detection threshold approximation line.

FIG. 3 is a perspective view of the vibration measuring device of this embodiment. FIG. 4 is a diagram showing the performance of the friction feel tester. FIG. 5 is an exploded view of the fixture. FIG. 6 is an exploded view of the sensor unit. FIG. 7 is a diagram showing the performance of the sensor. FIG. 8 is a graph showing vibration waveforms measured by the vibration measuring device.

In calculating I _SAI , I _FAI , and I _FAII , first, using the vibration measuring device 10, vibration information when the sample 100 (4 ply toilet paper 70) moves is measured (vibration measurement step). As shown in FIG. 3, the vibration measuring device 10 includes a friction feel tester 20, a fixture 40, and a sensor unit 50. In the vibration measurement device 10, a sample 100 supported by a fixture 40 is moved. The vibration measuring device 10 can acquire vibrations generated on the front or back surface of the sample 100 when the fixture 40 moves.

The friction feel tester 20 has the performance shown in FIG. 4. As shown in FIG. 3, the friction feel tester 20 includes a moving stage 21 and an arm 23. The moving stage 21 can move along the horizontal direction. The moving stage 21 moves the fixture 40 in the horizontal direction. For example, the moving stage 21 is moved by a linear motion mechanism driven by a motor and a ball screw. The arm 23 is arranged above the moving stage 21 and extends in the horizontal direction. Arm 23 is movable in the vertical direction. Arm 23 supports sensor unit 50.

Fixture 40 is a device for supporting sample 100. As shown in FIG. 5, the fixture 40 includes a base 41, a restraining plate 43, and a shock absorbing pad 45. The base 41 is fixed to the moving stage 21. The restraining plate 43 is fixed to the base 41 by a fixing member. The fixing member is, for example, a screw. The base 41 and the holding plate 43 are made of acrylic, for example, and are formed using an NC processing machine. The shock absorbing pad 45 is provided between the base 41 and the restraining plate 43. As shown in FIG. 7, the sample 100 is placed between the base 41 and the holding plate 43. By tightening the fixing member, the sample 100 is sandwiched between the base 41 and the shock absorbing pad 45. The shock absorbing pad 45 suppresses the sample 100 from shifting from the base 41.

As shown in FIG. 3, the sensor unit 50 is attached to the arm 23 of the friction feel tester 20 and positioned at a predetermined height. As shown in FIG. 6, the sensor unit 50 includes a diaphragm 57, a sensor 59, a contactor 51, and a sandwich plate 53.

The upper end of the diaphragm 57 is fixed to the arm 23. The diaphragm 57 is made of phosphor bronze, for example. Sensor 59 detects vibrations occurring in diaphragm 57. The sensor 59 is, for example, a strain gauge. The sensor 59 has the performance shown in FIG. Sensors 59 are arranged on both sides of diaphragm 57. The sensor 59 is fixed to the surface of the diaphragm 57 with adhesive, for example. A dynamic strain measuring device is connected to the sensor 59. The dynamic strain measuring instrument captures the amount of strain from the sensor 59 as an electrical signal and displays it as a voltage value. The contactor 51 and the sandwich plate 53 are fixed to the lower end of the diaphragm 57. The contactor 51 and the sandwich plate 53 are made of acrylic, for example. The contactor 51 and the sandwich plate 53 sandwich the diaphragm 57 between them. The contactor 51 and the sandwich plate 53 are fixed to the diaphragm 57 with screws. The bottom surface of the contactor 51 is a curved surface. When viewed from the horizontal direction and perpendicular to the moving direction of the moving stage 21, the bottom surface of the contactor 51 draws a semicircle. The bottom surface of the contactor 51 is in contact with the sample 100. The sandwich plate 53 has a substantially rectangular parallelepiped shape.

In the following, an example of the vibration measurement step is shown. In the vibration measurement step of this embodiment, the vibration measurement device 10 is installed so that the sample 100 moves along the horizontal direction. That is, _ISAI , _IFAI , and _IFAII of this embodiment are calculated based on vibration information measured with the vibration measuring device 10 installed so that the sample 100 moves along the horizontal direction. Ru.

In the vibration measurement step, when measuring vibration information of the sample 100 (4 ply toilet paper 70), the conductive wire of the sensor 59 is first connected to a dynamic strain measuring device. Next, the sample 100 is fixed to the fixture 40. The sample 100 is fixed to the fixture 40 so that the perforations of the sample 100 do not come into contact with the contacts 51 even if the sample 100 moves together with the fixture 40. Thereafter, vibration measurement is started by driving the friction feel tester 20.

The sample 100 is pushed from above by the contactor 51 with a predetermined force. For example, in this embodiment, the predetermined force is 0.5N. When measuring vibration information on the surface of the sample 100, the sample 100 is placed so that the front surface is in contact with the contactor 51 and the back surface is in contact with the base 41. When measuring vibration information on the back surface of the sample 100, the sample 100 is placed so that the back surface is in contact with the contactor 51 and the front surface is in contact with the base 41.

The moving stage 21 moves horizontally at a predetermined speed. The predetermined speed is desirably 1 mm/sec or more and 8 mm/sec or less. For example, in this embodiment, the predetermined speed is 5 mm/sec. The moving stage 21 is moved for a predetermined period of time. It is desirable that the predetermined time is 1 second or more. For example, in this embodiment, the predetermined time is 3 seconds. The sampling frequency is 10kHz. FIG. 8 is an example of a graph showing the vibration waveform of the sample 100 measured by the vibration measuring device 10.

The materials of each component of the vibration measuring device 10 are not necessarily limited to the materials mentioned above. The material of the diaphragm 57 is not limited to phosphor bronze, and may be other metals or materials other than metals. The material of the contactor 51 and the sandwich plate 53 is not limited to acrylic, but may be other materials.

After the vibration measurement step, an amplitude spectrum for each frequency is calculated based on the vibration information of the sample 100 (amplitude spectrum calculation step). An example of the amplitude spectrum calculation step will be shown below. The amplitude spectrum is calculated by, for example, Fourier transform.

Any periodic signal f(t) can be expressed as a sum of trigonometric functions. A periodic signal can be decomposed into its constituent trigonometric functions by performing Fourier series expansion. This makes it possible to find out the feature amount such as the frequency or spectrum included in the periodic signal.

When an arbitrary periodic signal f(t) is subjected to Fourier series expansion, it is expressed as equation (1). However, the Fourier coefficients a ₀ , a _n , and b _n are expressed by Equations (2), Equations (3), and Equations (4), respectively.

The periodic signal f(t) is expressed as a complex function as shown in equation (6) by using equation (5), which is Euler's formula. However, the Fourier coefficient g _n is expressed by equation (7).

Discrete Fourier Transform (DFT) is used to process digital signals. Equation (8) holds when the discrete signal f[n] is used. F[k] is called the frequency spectrum of f[n].

F[k] obtained from the DFT calculation is generally a complex number. If the real part of F[k] is Re{F[k]]} and the imaginary part of F[k] is Im{F[k]]}, then equations (9), (10), and (11 ) holds true. |F[k]| is called an amplitude spectrum. argF[k] is called a phase spectrum.

Calculation of the amplitude spectrum and phase spectrum requires N ² calculations. The fast Fourier transform (FFT) reduces the number of calculations to Nlog ₂ N by decomposing the DFT into a combination of two-point DFTs, thereby reducing the calculation time.

For example, among the vibration information obtained in the vibration measurement step, FFT processing is performed on information for the first one second immediately after the movement stage 21 is driven using numerical analysis software. For example, the number of data points is 8192 points, and a Hamming window is used as the window function. FIG. 9 is a diagram showing the calculated amplitude spectrum. In FIG. 9, the vertical axis is the amplitude spectrum.

After the amplitude spectrum calculation step, I _SAI , I _FAI , and I _FAII are calculated based on the amplitude spectrum and the value of the lowest vibration detection threshold approximation line (vibration stimulus value calculation step). An example of the vibration stimulation value calculation step will be shown below.

I _SAI , I _FAI , and I _FAII are calculated based on the amplitude spectrum and the value of the lowest vibration detection threshold approximation line. FIG. 10 is a diagram showing a vibration detection threshold curve. Mechanoreceptors are those that perceive the mechanical stimulation that is applied to the skin when a person touches an object. Mechanoreceptors are largely involved in human tactile sensation. Mechanoreceptors include Meissner's corpuscles, Pacinian corpuscles, Merkel's palps, and Ruffini terminals. Mechanoreceptors are classified into fast-adapting type I (FAI) and fast-adapting type II (FAII), based on the shape of the receptive field that combines the mechanoreceptor and the nerve fibers connected to it, and the nature of the nerve firing characteristics in response to mechanical stimulation. , classified into slow adaptation type I (SAI) and slow adaptation type II (SAII). The size of the receptive field in FAI and SAI is small, about several mm in diameter. On the other hand, FAII and SAII are large and have unclear boundaries. Furthermore, FAI fires in response to the velocity component of the applied stimulus. FAII fires in response to the acceleration component of the applied stimulus. SAI and SAII fire in response to the displacement of applied mechanical stimulation. Meissner corpuscles are classified as FAI. Pacinian corpuscles are classified as FAII. Merkel's touch panel is classified as SAI. The Ruffini terminal is classified as SAII.

Mechanoreceptors fire depending on the magnitude of mechanical stimulation applied to their receptive fields. This gives people a sense of touch. There is a vibration detection threshold curve as information regarding the threshold of vibration that a person can detect. As shown in FIG. 10, regarding SAI, the detection threshold does not change much even if the frequency is changed in the vicinity of 1 Hz or more and 100 Hz or less. Regarding FAI, the detection threshold becomes minimum at 10 Hz or more and 40 Hz or less. Regarding FAII, the detection threshold value becomes minimum at 100 Hz or more and 1000 Hz or less. The minimum vibration detection threshold approximation line is a line connecting the minimum vibration detection thresholds at each frequency. In FIG. 10, the lowest vibration detection threshold approximation line is indicated by a thick line. If a stimulus with an amplitude greater than the minimum vibration detection threshold curve is applied, one of the receptors will fire, and the person will perceive a tactile sensation. Furthermore, the SAII vibration detection threshold curve is omitted because it has a higher threshold than any other receptor in any frequency band and does not affect the lowest vibration detection threshold curve.

FIG. 11 is a diagram showing a minimum vibration detection threshold approximation line. The minimum vibration detection threshold curve shown in FIG. 10 can be represented by the minimum vibration detection threshold approximation line shown in FIG. Approximate expressions for the lowest vibration detection threshold approximation line are defined by Equation (12), Equation (13), Equation (14), and Equation (15).

However, since SAI is a displacement sensor, the value of L _SAI needs to be greater than 0 in all samples. At frequencies below 3 Hz, the value of _LSAI is determined to match the value of the sample that provides the minimum amplitude spectrum.

L _SAI , L _FAI , and L _FAII are vibration detection threshold approximation lines of SAI, FAI, and FAII, respectively. f is the frequency of vibration stimulation. Further, L _{FAI, 40 Hz} and L _{F A II, 250 Hz} indicate the threshold value at 40 Hz and the threshold value at 250 Hz, respectively.

FIG. 12 is a diagram showing an amplitude spectrum and a minimum vibration detection threshold approximation line. FIG. 12 is a graph showing a logarithmic representation of the minimum vibration detection threshold approximation line, and a logarithmic representation of the graph shown in FIG. 9. In FIG. 12, the solid line is a logarithmic representation of the graph shown in FIG. 9, and the broken line is a logarithmic representation of the lowest vibration detection threshold approximation line. In FIG. 12, the portion exceeding the minimum vibration detection threshold approximation line is the vibration stimulation value. The vibration stimulation values _Ii (I _SAI , I _FAI , and I _FAII ) are determined by Equation (16), Equation (17), and Equation (18).

P _i is the amplitude spectrum of the i-th data in the periodogram. L _i is the i-th value of the lowest vibration detection threshold approximation line. f _l and f _h are the minimum and maximum values in frequency of each frequency band. I _SAI , I _FAI , and I _FAII are calculated by dividing each receptive field showing the lowest vibration detection threshold approximation line.

The portion where the measured vibration exceeded the threshold approximation line in the graph shown in FIG. 12 was calculated using equations (16) to (18). FIG. 13 is a diagram showing an example of calculated I _SAI , I _FAI , and I _FAII when the vibration on the surface of the sample 100 is measured. FIG. 14 is a diagram showing an example of the calculated I _SAI , I _FAI , and I _FAII when the vibration of the back surface of the sample 100 is measured.

Table 1 is a table showing the sensory evaluation of an example, which is an example of the toilet roll product of the present embodiment. Table 2 is a table showing sensory evaluations for comparative examples. In Tables 1 and 2, the inclination (°) of the embossed pattern is the angle α between the first reference line A1 and the first straight line B1 shown in FIG. I _SAI (Table) is the I _SAI of the surface. I _SAI (back) is the I _SAI of the back side. I _FAI (Table) is the I _FAI of the surface. I _FAI (back) is the I _FAI on the back side. I _FAII (Table) is the I _FAII of the surface. I _FAII (back) is I _FAII on the back side. I _SAI (difference) is the value obtained by subtracting the I _SAI of the back side from the I _SAI of the front side. I _FAI (difference) is the value obtained by subtracting the I _FAI of the back side from the I _FAI of the front side. I _FAII (difference) is the value obtained by subtracting I _FAII on the back side from I _FAII on the front side.

Sensory evaluation was performed on the Examples and Comparative Examples. Specifically, sensory evaluation was performed on softness, smoothness, difference between front and back sides, and embossed shape retention. Sensory evaluation was conducted on 60 people. 60 people evaluated the softness, smoothness, difference between front and back sides, and emboss shape retention of each Example and each Comparative Example on a scale of 1 to 5 points. In the columns of softness, smoothness, difference between front and back sides, and emboss shape retention in Tables 1 and 2, "Excellent" indicates that the average score of 60 people is 4 points or more, and "Good" indicates that the average score is 4 points or more. indicates that the average score is 3 points or more and less than 4 points, and "unsatisfactory" indicates that the average score is less than 3 points. The condition that the toilet roll product 60 should satisfy is that the sensory evaluations of softness, smoothness, difference between front and back sides, and embossed shape retention are all "good" or better.

Softness is the softness felt when using the toilet roll product 60. In the sensory evaluation regarding softness, "excellent" means that it feels especially soft, "good" means that it feels soft, and "poor" means that it feels hard.

Smoothness is the smoothness felt when using the toilet roll product 60. In the sensory evaluation of smoothness, "Excellent" means that it feels particularly smooth, "Good" means that it feels smooth, and "Poor" means that it is not smooth enough and feels painful to the skin. .

The front-back difference is the front-back difference (difference in tactile sensation between the front and back surfaces) that is felt when the toilet roll product 60 is used. In the sensory evaluation regarding the difference between the front and back sides, "Excellent" means that you do not feel any difference between the front and back sides, "Good" means that there is some difference between the front and back sides but it is not noticeable, and "Bad" means that there is no difference between the front and back sides. This means that it is large and difficult to use.

Emboss shape retention is the resistance of the embossed pattern 80 (embossed portion 81) to crushing when the rolled toilet roll product 60 is unwound and used. In the sensory evaluation regarding emboss shape retention, "excellent" means that the emboss pattern 80 remains firmly, and "good" means that the emboss pattern 80 is slightly crushed in some places, but at a level that is not noticeable. "Not possible" means that the embossed pattern 80 is thin and difficult to use.

As shown in Table 1, Examples 1 to 5 are toilet roll products in which a 2-ply toilet paper 70 having a single embossed pattern is wound into a roll. The basis weight of the toilet paper 70 of the first to fifth embodiments is 11 g/m ² or more and 19 g/m ² or less. In the first to fifth embodiments, the winding length is 63 m or more and 128 m or less, and the winding diameter is 103 mm or more and 151 mm or less. The area ratio of the embossed pattern 80 in the first to fifth embodiments is 30% or more and 45% or less, or 55% or more and 70% or less. The I _SAI of the 4 ply toilet paper 70 measured using the vibration measuring device 10 is 300 V/s or more and 800 V/s or less, the I _FAI is 8500 V/s or more and 11000 V/s or less, and the I _{FA II} is 8000 V/s or less. s or more and 11,000 V/s or less. The difference between the I _SAI on the front side of the toilet paper 70 and the I _SAI on the back side is −400 V/s or more and 400 V/s or less. The difference between the I _FAI on the front side of the toilet paper 70 and the I _FAI on the back side is −3000 V/s or more and 3000 V/s or less. The difference between I _FAII on the front side and I _FAII on the back side of the toilet paper 70 is −2500 V/s or more and 2500 V/s or less. In Examples 1 to 5, the sensory evaluations of softness, smoothness, difference between front and back surfaces, and emboss shape retention are all "good" or better. The first to fifth examples are toilet roll products that are comfortable to use.

As shown in Table 2, in the first comparative example, the basis weight is higher than 19.0 g/m ² (outside the range of 11.0 g/m ² to 19.0 g/m ² ). The _ISAI of the front and back surfaces is greater than 800 V/s (outside the range of 300 V/s or more and 800 V/s or less). The I _FAI of the surface is greater than 11000 V/s (outside the range of 8500 V/s or more and 11000 V/s or less). Surface I _FAII is less than 11,000 V/s (outside the range of 8,000 V/s or more and 11,000 V/s or less). In the first comparative example, the sensory evaluation of softness is "unsatisfactory".

As shown in Table 2, in the second comparative example, the basis weight is lower than 11.0 g/m ² (outside the range of 11.0 g/m ² to 19.0 g/m ² ). _ISAI on the back surface is less than 300 V/s (outside the range of 300 V/s or more and 800 V/s or less). The I _FAI of the front and back surfaces is less than 8,500 V/s (outside the range of 8,500 V/s or more and 11,000 V/s or less). _IFAII of the surface is less than 8000 V/s (outside the range of 8000 V/s or more and 11000 V/s or less). In the second comparative example, the sensory evaluation of smoothness and emboss shape retention is "unsatisfactory".

As shown in Table 2, in the third comparative example, the area ratio of the embossed pattern is 50% (outside the range of 30% to 45%, or 55% to 70%). The inclination of the embossed pattern is 4° (outside the range of 0° or more and 3° or less). In the third comparative example, the sensory evaluation of embossed shape retention is "unsatisfactory".

As shown in Table 2, in the fourth comparative example, the area ratio of the embossed pattern is 75% (outside the range of 30% to 45%, or 55% to 70%). The depth of the embossed pattern 80 is 0.40 mm (outside the range of 0.01 mm or more and 0.30 mm or less). _ISAI of the surface is greater than 800 V/s (outside the range of 300 V/s or more and 800 V/s or less). The I _FAI of the surface is greater than 11000 V/s (outside the range of 8500 V/s or more and 11000 V/s or less). _IFAII of the surface is larger than 11000V/s (outside the range of 8000V/s or more and 11000V/s or less). The difference between I _FAI on the front surface and I _FAI on the back surface is larger than 3000 V/s (outside the range of -3000 V/s or more and 3000 V/s or less). The difference between I _FAII on the front surface and I _FAII on the back surface is larger than 2500 V/s (outside the range of -2500 V/s or more and 2500 V/s or less). In the fourth comparative example, the sensory evaluation of the difference between the front and back surfaces is "unacceptable".

As shown in Table 2, in the fifth comparative example, the emboss pattern method is double emboss. In double-embossed toilet roll products, 2-ply toilet paper is stacked so that the end faces of the embossed portions of the embossed pattern face each other. In double-embossed toilet roll products, the voids between the two plies of toilet paper improve water absorption and softness, but the embossed pattern tends to collapse when rolled. In the fifth comparative example, the sensory evaluation of embossed shape retention is "unsatisfactory".

As explained above, the toilet roll product 60 of this embodiment is a product obtained by winding up a 2-ply toilet paper 70 having a single embossed emboss pattern 80 into a roll shape. The basis weight per ply of the toilet paper 70 is 11 g/m ² or more and 19 g/m ² or less. The winding length is 63 m or more and 128 m or less. The winding diameter is 103 mm or more and 151 mm or less. The area ratio of the embossed pattern 80 is 30% or more and 45% or less, or 55% or more and 70% or less. A first region where the frequency is 1 Hz or more and 3 Hz or less among the vibration stimulation values calculated based on the vibration characteristics of the 4 ply toilet paper 70 measured using the vibration measurement device 10 and the value of the lowest vibration detection threshold approximation line. The first vibration stimulation value (I _SAI ) is 300 V/s or more and 800 V/s or less. Among the vibration stimulation values, the second vibration stimulation value ( _IFAI ) in the second region where the frequency is greater than 3 Hz and less than 40 Hz is 8500 V/s or more and 11000 V/s or less. Among the vibration stimulation values, the third vibration stimulation value (I _FAII ) in the third region where the frequency is greater than 40 Hz and less than 1000 Hz is greater than or equal to 8000 V/s and less than or equal to 11000 V/s. The difference between the first vibration stimulation value (I _SAI ) for the front surface of the toilet paper 70 and the first vibration stimulation value (I _SAI ) for the back surface of the toilet paper 70 is −400 V/s or more and 400 V/s or less. The difference between the second vibration stimulation value ( _IFAI ) for the front surface of the toilet paper 70 and the second vibration stimulation value ( _IFAI ) for the back surface of the toilet paper 70 is −3000 V/s or more and 3000 V/s or less. The difference between the third vibration stimulation value (I _FAII ) for the front surface of the toilet paper 70 and the third vibration stimulation value (I _FAII ) for the back surface of the toilet paper 70 is −2500 V/s or more and 2500 V/s or less.

Since the toilet paper 70 has the above-mentioned basis weight, roll length, and roll diameter, and has the single-embossed emboss pattern 80, the toilet roll product 60 has appropriate strength and bulk, and has the roll length. It is long, has a good tactile feel and cosmetic appearance during use, and is excellent in portability and space saving during storage. Further, by setting the area ratio of the embossed pattern 80 to 30% or more or 70% or less, the difference between the front and back surfaces becomes small. When the area ratio of the embossed pattern 80 is 45% or less or 55% or more, the embossed pattern 80 becomes difficult to collapse. More specifically, the edges of the embossed portions 81 are easily maintained, thereby making the embossed portions 81 less likely to collapse. Furthermore, since the first vibration stimulation value (I _SAI ), the second vibration stimulation value ( _IFAI ), and the third vibration stimulation value (I _FAII ) are each within the above-mentioned ranges, the difference between the front and back surfaces becomes smaller, and The embossed pattern 80 becomes more difficult to collapse. Therefore, the toilet roll product 60 of this embodiment has appropriate strength and bulk, has a long roll length, has good tactile feel and cosmetic appearance during use, and is excellent in portability and space saving during storage. , the difference between the front and back sides is small and the shape retention of the embossed pattern is excellent. As a result, the toilet roll product 60 can improve the level of sensory evaluation of softness, smoothness, difference between front and back, and embossed shape retention, as shown in Table 1.

In the toilet roll product 60 of this embodiment, the depth of the embossed pattern 80 is 0.01 mm or more and 0.30 mm or less.

Thereby, the toilet roll product 60 of the present embodiment can further improve the tactile sensation and cosmetic properties during use, and can further reduce the difference between the front and back sides.

In the toilet roll product 60 of this embodiment, the embossed pattern 80 includes a plurality of embossed portions 81 that are recessed portions. If a straight line passing through the center of gravity of one embossed part 81 and the center of gravity of the embossed part 81 closest to the embossed part 81 is defined as a first straight line B1, and a straight line perpendicular to the first straight line B1 is defined as a second straight line B2, the flow The angle γ between the first reference line A1 parallel to the direction DM and the second straight line B2 is larger than the angle α between the first reference line A1 and the first straight line B1.

Thereby, the toilet roll product 60 of this embodiment can improve the feel on the skin and the fit on the fingertips. According to the toilet roll product 60 of this embodiment, the tactile sensation during use is improved.

In the toilet roll product 60 of this embodiment, the angle α between the first reference line A1 and the first straight line B1 is 0° or more and 3° or less.

Thereby, the toilet roll product 60 of this embodiment can further improve embossed shape retention.

In the toilet roll product 60 of this embodiment, the thickness of the toilet paper 70 is 0.45 mm/10 ply or more and 1.20 mm/10 ply or less.

Thereby, the toilet roll product 60 of this embodiment can be easily wound up into a roll even though it has the above-mentioned basis weight, roll length, and roll diameter.

In the toilet roll product 60 of this embodiment, the dry longitudinal strength, which is the longitudinal tensile strength during drying, is 280 gf/25 mm or more and 550 gf/25 mm or less. The dry transverse strength, which is the tensile strength in the transverse direction when dried, is 80 gf/25 mm or more and 210 gf/25 mm or less.

Thereby, the toilet roll product 60 of this embodiment can be made difficult to tear and can have appropriate softness.

(Modified example)
FIG. 15 is a plan view of a modified emboss pattern. Note that the same components as those described in the embodiments described above are given the same reference numerals and redundant explanations will be omitted.

As shown in FIG. 15, the toilet paper 70A has an embossed pattern 80A. The embossed pattern 80A is formed by embossing. The emboss pattern 80A is a so-called single emboss. An embossed pattern 80A is formed by pressing a convex mold from one side of the 2-ply stacked toilet paper 70A. The depth of the embossed pattern 80A is preferably 0.01 mm or more and 0.30 mm or less. More preferably, the depth of the embossed pattern 80A is 0.03 mm or more and 0.25 mm or less.

The emboss pattern 80A includes a plurality of emboss parts 81 and a plurality of auxiliary emboss parts 82. In the toilet paper 70A, the first straight line B1 is parallel to the first reference line A1. That is, the angle between the first straight line B1 and the first reference line A1 is 0°. The angle that the second straight line B2 makes with the first reference line A1 is 90°. Therefore, in the toilet paper 70A, the first direction D1 is parallel to the flow direction DM, and the second direction D2 is parallel to the width direction DW.

The area ratio of the embossed pattern 80A is 30% or more and 45% or less, or 55% or more and 70% or less. The area ratio of the embossed pattern 80A is the ratio that the embossed portion 81 occupies with respect to the unit area of the surface of the toilet paper 70A. If the sum of the areas of all the embossed parts 81 in the unit length toilet paper 70A is S1, and the area of the unit length toilet paper 70A is S2, the area ratio is calculated as (S1/S2) x 100. . S1 does not include the area of the auxiliary embossed portion 82.

The auxiliary embossed portion 82 is a recessed portion smaller than the embossed portion 81. The auxiliary embossed portion 82 is arranged between two adjacent embossed portions 81 in the second direction D2. The auxiliary embossing section 82 connects the two embossing sections 81. The auxiliary embossing portion 82 extends in a direction forming an angle with respect to the first direction D1 and the second direction D2. One end of the auxiliary embossed portion 82 is connected to an end of one embossed portion 81 in the first direction D1. The other end of the auxiliary embossed portion 82 is connected to the intermediate portion in the first direction D1 of the embossed portion 81 adjacent to the embossed portion 81 in the second direction. When viewed from the thickness direction of the toilet paper 70, one embossed portion 81 and one auxiliary embossed portion 82 form a substantially comma shape. The substantially comma shape is substantially an inverted comma shape when viewed from the opposite direction.

Note that in the modified toilet paper 70A, the first straight line B1 does not necessarily have to be parallel to the first reference line A1. The first straight line B1 may form an angle with the first reference line A1. The angle that the first straight line B1 makes with the first reference line A1 is preferably 0° or more and 3° or less.

As explained above, in the toilet paper 70A of the modified example, the embossed pattern 80A is a recessed part that is disposed between two adjacent embossed parts 81 in the direction parallel to the second straight line B2 and that is connected to the embossed part 81. An auxiliary embossing section 82 is provided. A comma shape is drawn by one embossed part 81 and one auxiliary embossed part 82.

When forming the emboss pattern 80A by embossing, the toilet paper 70A is sandwiched between a rubber roll and an emboss roll having convex portions. Since the toilet paper 70A includes the auxiliary embossing portion 82, the convex portion of the embossing roll comes into uniform contact with the rubber roll. Therefore, the modified toilet paper 70A can slow down the deterioration rate of the rubber roll used for embossing.

10 Vibration measuring device 20 Friction tester 21 Moving stage 23 Arm 40 Fixture 41 Base 43 Holding plate 45 Shock absorption pad 50 Sensor unit 51 Contactor 53 Sandwich plate 57 Vibration plate 59 Sensor 60 Toilet roll product 70, 70A Toilet paper 80, 80A Embossed pattern 81, 81a, 81b Embossed part 82 Auxiliary embossed part D1 First direction D2 Second direction DM Flow direction DW Width direction

Claims (7)

A toilet roll product made by winding up a 2-ply toilet paper having a single embossed pattern into a roll,
The basis weight per ply of the toilet paper is 11 g/m ² or more and 19 g/m ² or less,
The winding length is 63 m or more and 128 m or less,
The winding diameter is 103 mm or more and 151 mm or less,
The area ratio of the embossed pattern is 30% or more and 45% or less, or 55% or more and 70% or less,
Among the vibration characteristics of the toilet paper of 4ply measured using a vibration measurement device and the vibration stimulation value calculated based on the value of the lowest vibration detection threshold approximation line, in the first region where the frequency is 1 Hz or more and 3 Hz or less. The first vibration stimulation value is 300 V/s or more and 800 V/s or less,
Among the vibration stimulation values, a second vibration stimulation value in a second region whose frequency is greater than 3 Hz and less than 40 Hz is 8500 V/s or more and 11000 V/s or less,
Among the vibration stimulation values, a third vibration stimulation value in a third region where the frequency is greater than 40 Hz and less than 1000 Hz is greater than or equal to 8000 V/s and less than or equal to 11000 V/s,
The difference between the first vibration stimulation value regarding the front surface of the toilet paper and the first vibration stimulation value regarding the back surface of the toilet paper is −400 V/s or more and 400 V/s or less,
The difference between the second vibration stimulation value regarding the front surface of the toilet paper and the second vibration stimulation value regarding the back surface of the toilet paper is −3000 V/s or more and 3000 V/s or less,
A difference between the third vibration stimulation value regarding the front surface of the toilet paper and the third vibration stimulation value regarding the back surface of the toilet paper is −2500 V/s or more and 2500 V/s or less. A toilet roll product. The toilet roll product according to claim 1, wherein the depth of the embossed pattern is 0.01 mm or more and 0.30 mm or less. The embossed pattern includes a plurality of embossed portions that are recessed portions,
A straight line passing through the center of gravity of one of the embossed parts and the center of gravity of the embossed part closest to the embossed part is defined as a first straight line, and a straight line perpendicular to the first straight line is defined as a second straight line, which is parallel to the flow direction. The toilet roll product according to claim 1 or 2, wherein the angle between the reference line and the second straight line is larger than the angle between the reference line and the first straight line. The toilet roll product according to claim 3, wherein the angle between the reference line and the first straight line is 0° or more and 3° or less. The embossed pattern includes an auxiliary embossed part that is a recess that is arranged between two adjacent embossed parts in a direction parallel to the second straight line and connected to the embossed part,
The toilet roll product according to claim 3 or 4, wherein a comma shape is drawn by one of the embossed portions and one of the auxiliary embossed portions. The toilet roll product according to any one of claims 1 to 5, wherein the toilet paper has a thickness of 0.45 mm/10 ply or more and 1.20 mm/10 ply or less. The dry longitudinal strength, which is the tensile strength in the longitudinal direction when dried, is 280 gf/25 mm or more and 550 gf/25 mm or less,
The toilet roll product according to any one of claims 1 to 6, wherein the dry lateral strength, which is the tensile strength in the lateral direction during drying, is 80 gf/25 mm or more and 210 gf/25 mm or less.

Images