Toilet roll

Abstract

[Problem] To provide a toilet roll that achieves both quality aspects regarding the feel against the skin, such as softness and a light and airy texture, and functional properties such as sufficient strength and water absorbency that are necessary for use with a shower toilet, thereby minimizing dissatisfaction with the toilet roll both in use with a conventional toilet and in use with a shower toilet. [Solution] The problem is solved by providing a toilet roll comprising toilet paper that has a winding length of 20-40 m and a roll diameter of 110-130 mm that is wound around a paper tube, wherein the toilet paper is subjected to laminate embossing, the dry tensile strength in the vertical direction is 250-360 cN / 25 mm, the dry tensile strength in the horizontal direction is 65-120 cN / 25 mm, the aspect ratio is 2.9-3.8, the wet tensile strength in the vertical direction is 40- 80 cN / 25 mm, the wet tensile strength in the horizontal direction is 16-35 cN / 25 mm, and the ratio of the wet tensile strength in the horizontal direction to the dry tensile strength in the horizontal direction is 0.20-0.40.

Description

Toilet roll

[0001] The present invention relates to a toilet roll in which a strip of toilet paper is wound into a roll.

[0002] As consumer preferences diversify, toilet rolls are being developed to meet various preferences. For example, there are products called standard or regular products, which are two-ply toilet paper rolls with a roll length of about 25 to 30 m, products called long products with a roll length of about 75 to 90 m, which is three times longer than regular products, and products called shower toilet products, which are roll lengths similar to regular products but with toilet paper that has particularly improved wet strength and water absorbency.

[0003] Regular products are the traditional long roll products, which have a relatively high basis weight and thickness compared to long products, and in recent years have become a high-quality product group, and are preferred by consumers who prioritize quality such as skin damage and softness and fluffiness. Long products are also preferred by consumers who prioritize benefits such as fewer purchases and replacements. Shower toilet wipes are preferred by consumers who prioritize functionality such as ease of wiping and a sense of security when wiping away feces and urine along with the moisture that has adhered to the skin after washing the defecation and urination areas with warm or cold water in a shower toilet.

[0004] Products for shower toilets have improved wet strength, sheet thickness, strength, and the ability to maintain gaps between plies by using, for example, temporary wet strength agents such as wet strength agents or cationic aldehyde-modified polyacrylamide copolymers, or by using laminate embossing technology in which embossed plies are laminated and bonded together with adhesive.

[0005] Japanese Patent Laid-Open No. 08-56868 Japanese Patent Laid-Open No. 2006-320688 Japanese Patent Laid-Open No. 2011-153387

[0006] However, products for shower toilets are inferior to standard products in terms of quality, such as softness and fluffiness, and water-dissolvability, because the stiffness of the paper is increased to create a firm feel, they tend to feel crunchy due to adhesives, and they have poor water-dissolvability due to high levels of wet strength agents, etc. These can be dissatisfaction points for consumers who prefer shower toilets.

[0007] On the other hand, as flushing toilets have become more widespread and familiar, the applicant's research has revealed that some consumers who used regular toilets because they placed importance on quality such as softness and fluffiness feel that the absorbency and firmness of the paper are insufficient when used in flushing toilets.

[0008] Therefore, the main object of the present invention is to provide a toilet roll that combines quality aspects related to the feel of a normal product, such as softness and fluffiness, with functionality such as firmness and absorbency of a paper roll for a shower toilet, and that is unlikely to cause dissatisfaction whether used normally or in a toilet with a flushing function.

[0009] A first means for solving the above problem is a toilet roll in which two-ply toilet paper, each consisting of two sheets stacked together, is wound around a paper tube to a roll length of 20 to 40 m and a roll diameter of 110 to 130 mm, wherein the toilet roll is: sheets each having embossed depressions on one side and protrusions corresponding to the depressions on the other side, stacked so that the convex portions face each other and bonded at the tops of the protrusions with an adhesive; the dry tensile strength in the longitudinal direction is 250 cN / 25 mm or more and 360 cN / 25 mm or less, and the dry tensile strength in the transverse direction is 65 cN / 25 mm or more and 120 cN / 25 mm or less; the ratio of the dry tensile strength in the longitudinal direction to the dry tensile strength in the transverse direction (dry tensile strength in the longitudinal direction / dry tensile strength in the transverse direction) is 2.9 or more and 3.8 or less; The toilet roll has a wet tensile strength in the longitudinal direction of 40 cN / 25 mm or more and 80 cN / 25 mm or less, a wet tensile strength in the transverse direction of 16 cN / 25 mm or more and 35 cN / 25 mm or less, and a ratio of the wet tensile strength in the transverse direction to the dry tensile strength in the transverse direction (wet tensile strength in the transverse direction / dry tensile strength in the transverse direction) of 0.20 to 0.40.

[0010] A second aspect is the toilet roll according to the first aspect, wherein the ratio of the wet tensile strength in the machine direction to the dry tensile strength in the machine direction (wet tensile strength in the machine direction / dry tensile strength in the machine direction) is 0.10 to 0.25.

[0011] Another method is to stack four sheets of toilet paper and press the measuring terminal into a compression tester to measure 0.5 gf / cm ２ Load T0 to 50gf / cm ２ The toilet roll according to the first or second means, wherein the stretchability, which is the displacement (T0-Tm) up to Tm under load, is 1.0 mm or more.

[0012] Another means is a toilet roll according to the first, second and other means, in which the two sheets are laminated in a nested form, with the raised portions of one sheet positioned in a portion other than the raised portions of the other sheet, and the two sheets are bonded together by adhesive applied to the raised portions of the sheet positioned on the outer surface of the roll.

[0013] According to the present invention, a toilet roll is provided which combines quality aspects relating to the feel of the toilet, such as softness and fluffiness like regular products, with functionality such as firmness and water absorbency like that of a toilet for shower use, and is unlikely to cause dissatisfaction whether used in a toilet with a flushing function or in a regular use.

[0014] Fig. 1 is a perspective view of a toilet roll according to an embodiment of the present invention. Fig. 2 is a schematic cross-sectional view of toilet paper according to an embodiment of the present invention. Fig. 3 is a diagram showing an example of a plan view of toilet paper according to an embodiment of the present invention. Fig. 4 is a schematic diagram for explaining a method for measuring sheet stretchability according to the present invention. Fig. 5 is a schematic diagram for explaining a method for measuring MMD according to the present invention. Fig. 6 is a schematic diagram for explaining a method for measuring roll winding hardness according to the present invention. Fig. 7 is a schematic diagram for explaining a procedure for measuring roll winding hardness according to the present invention. Fig. 8 is a schematic diagram for explaining a procedure for measuring roll softness according to the present invention.

[0015] Next, embodiments of the present invention will be described in detail below with reference to the drawings.

[0016] As shown in Figure 1, the toilet roll according to this embodiment is cylindrical in shape and is made by winding two-ply water-decomposable toilet paper 10, which is made up of two laminated sheets, a first sheet 11 and a second sheet 12, around a paper tube (also called a tube core) 20. In the toilet roll 1 of this embodiment, the toilet paper is wound with the first sheet 11 on the outer surface and the second sheet 12 on the inner surface.

[0017] In the case of toilet rolls, the roll length of a group of products called 2-ply regular products is about 25 to 30 m, but the roll length of the toilet roll 1 according to this embodiment is 20 to 40 m, preferably 20 to 30 m, and is the same as that of a group of products called regular products.

[0018] The roll diameter L2 (diameter) of the toilet roll 1 according to this embodiment is 110 to 130 mm, preferably 110 to 120 mm. Holders for setting toilet rolls are generally manufactured based on JIS P 4501, with a standard diameter of 120 mm. The toilet roll according to this embodiment has a roll diameter of 110 to 130 mm or less, and can be set in a standard holder. Furthermore, if the roll diameter is less than 110 mm in relation to the roll length, the toilet paper will be tightly wound, which will likely result in a deterioration in quality aspects such as feel. Here, the roll diameter L2 is a value measured using a diameter ruler manufactured by Muratec KDS Corporation or an equivalent device. The roll width L1 of the toilet roll 1 according to this embodiment is not limited, but is preferably 100 to 120 mm. The outer diameter L3 of the cardboard tube 20 is also not limited, but is preferably 34 to 42 mm.

[0019] The toilet paper 10 wound into the toilet roll 1 according to this embodiment is a two-ply toilet paper 10 formed by laminating two sheets (a first sheet 11 and a second sheet 12) having embossed recesses 32 and protrusions 31. The basis weight of each sheet 11, 12, i.e., the basis weight per ply, is 15.5 to 20.0 g / m ２ , preferably 17.0 to 19.0 g / m2. If the basis weight of each sheet 11, 12 is within this range, it is possible to ensure a sufficient softness and fluffy feel to the touch. It is also possible to ensure sufficient wiping ability and absorbency for moist skin, as well as a sense of security when wiping. In particular, it is possible to provide a toilet roll 1 that is equal to or better than the conventional products known as "normal products," and that has the same wiping ability and absorbency for moist skin, as well as a sense of security when wiping, as well as the same as the conventional products known as "shower toilet" products, making it unlikely for consumers to be dissatisfied with its quality and functionality.

[0020] The thickness of the toilet paper 10, i.e., the thickness of two plies, is 200 to 300 μm, more preferably 230 to 290 μm. If the paper thickness is within this range, it is possible to obtain a toilet roll 1 that is unlikely to cause consumer dissatisfaction in terms of quality and functionality. The basis weight can be adjusted, for example, by the fiber basis weight and crepe rate, and the paper thickness can be adjusted, for example, by the presence or absence of calendering, calender pressure, embossing, crepe rate, etc.

[0021] The basis weight (US basis weight) is measured in accordance with the provisions of JIS P 8124. The paper thickness is measured by thoroughly conditioning the test specimen under the conditions of JIS P 8111 (1998) (usually for about 8 hours), and then measuring the two-ply specimen under the same conditions using a PEACOCK H-type dial thickness gauge (thickness measuring device) (manufactured by Ozaki Seisakusho). Specifically, after ensuring that there is no dirt or dust between the plunger and the measuring table, the plunger is lowered onto the measuring table, the dial thickness gauge's scale is moved to set the zero point, the plunger is then raised, the sample is placed on the testing table, and the plunger is opened to 700 μm, and the lever is lowered in one go to read the gauge. During measurement, the plunger is simply placed on the test table, not pressed down. The plunger terminal is positioned so that the 10 mm diameter circular flat surface is perpendicular to the paper surface, and the load during paper thickness measurement is approximately 70 gf. The paper thickness is the average value obtained by performing 10 measurements.

[0022] On the other hand, the disintegrated freeness of the toilet paper according to this embodiment is preferably 500 cc or more and 650 cc or less, more preferably 500 cc or more and 620 cc or less, and particularly preferably 500 cc or more and 590 cc or less. The disintegrated freeness can be adjusted by the degree of beating of the pulp fibers. In other words, a lower value of disintegrated freeness indicates that the pulp fibers are more beaten, and a higher value indicates that the pulp fibers are less beaten. This disintegrated freeness range is slightly higher than that of toilet paper in the general standard product group. By setting the degree of beating of the pulp fibers to a low degree and setting the disintegrated freeness within the above range, and by adopting other configurations according to the present invention, it becomes particularly easy to achieve both quality equivalent to standard products and functionality equivalent to those for shower toilets.

[0023] The remaced freeness is measured by disintegrating toilet paper using a standard disintegrator in accordance with JIS P 8220-1 and JIS P 8220-2:2012 (Pulp - Disintegration Method), and the resulting slurry is measured by the Canadian Standard Freeness Method of JIS P 8121-2:2012 (Testing Method for Pulp Freeness). More specifically, the remaced freeness is measured as follows. In the following measurement, measurements are made twice for the same sample, and the measured value is the average of the two values. If the two measured values ​​differ from the average by 2% or more, an additional test is conducted.

[0024] (Disintegration of Toilet Paper) Tear a sheet (toilet paper) into approximately 2 cm pieces by hand to prepare a bone-dry sample of 30±0.5 g. Immerse 30±0.5 g of the torn sheet in 2000 mL of water (concentration: 1.5% by mass) for at least 4 hours. The water temperature during this process should be 20±5°C. After at least 4 hours have passed, place the 30±0.5 g sheet and 2000 mL of water into a standard disintegrator. After checking the water temperature, disintegrate for 10 minutes. After 10 minutes, collect approximately one teaspoonful of the sample into a measuring cylinder, dilute it with water, and visually confirm whether the fibers have been disintegrated. If sufficient disintegration is confirmed, measure the freeness of the disintegrated solution as described below. If disintegration is insufficient, disintegrate again. At this time, visually check every 2-3 minutes to see if the fibers have been disintegrated, and repeat the process until disintegration is complete. However, the maximum time is 30 minutes. In this way, the fibers can be defibrated without changing their original properties. The defibration count of the standard defibrator, 1230 rpm, is the count value when the defibrator is operated for 10 minutes.

[0025] (Freeness Measurement) Measurement is performed in accordance with the Canadian Standard Freeness Test (JIS P 8121-2 2012) using the following Canadian Standard Freeness Tester. The Canadian Standard Freeness Tester used has the following specifications or an equivalent. The filter bottle is, for example, a bronze cylinder, with a sieve plate (a circular plate with 97 0.5 mm diameter holes per cm2) set at the bottom. The hole diameter of the cock for introducing air is 4.8 mm. The measuring funnel is, for example, made of brass, with a diameter of 203 mm at the open top and a total length of 278 mm, and the apex angle of the main cone is machined to 29.5±0.5°. The funnel also has a precisely machined bottom hole at the bottom and a side tube attached to the side. The minimum diameter of the bottom hole is 3.1 mm, and is adjusted so that 530 ± 5.3 mL of water is discharged per minute when 725 ± 5 mL of water (20 ± 5°C) is supplied to the funnel per minute. The side tube is a hollow tube with an inner diameter of 12.7 mm that penetrates the wall of the funnel. The volume of water between the bottom of the funnel and the overflow level is adjusted to 23.5 ± 0.2 mL.

[0026] Next, a measurement liquid with a solids concentration of 0.3% by mass is prepared from the disaggregated liquid obtained in the above "(Disaggregated Toilet Paper)" as follows. First, the disaggregated liquid obtained in the above "(Disaggregated Toilet Paper)" is diluted to a concentration of 0.3 to 1.0% by mass. Approximately 500 g of the diluted sample is collected and placed in a container for weighing, and weighed to within 0.5 g (weighed value A). Next, No. 2 filter paper is placed in a hot air dryer (105±2°C), dried to a constant weight, and weighed to within 0.01 g (weighed value B). The No. 2 filter paper is placed in a Buchner funnel and wetted with water, and suction is initiated. Next, approximately 500 g of the collected sample is transferred to the Buchner funnel, and the water is sucked out. After suction is completed, the No. 2 filter paper is placed in a hot air dryer (105±2°C), dried to a constant weight, and weighed to within 0.01 g (weighed value B). Remove the No. 2 filter paper, pass it through a sheet dryer set at 120°C twice, place it in a hot air dryer (105±2°C) for 10 minutes, and then remove it. Weigh the mass of the No. 2 filter paper with the removed fiber to an accuracy of 0.01 g (weighed value C).

[0027] After determining the weighed values ​​A to C as described above, calculate the solids concentration X (mass %) of the sample using the following formula (rounding width: 0.01): Solids concentration X = (((weighed value C) - (weighed value B)) / (weighed value A)) × 100 Based on the calculated solids concentration X (mass %), determine the amount D of the diluted macerating liquid to be collected using the following formula so that it contains 3 g of bone-dry pulp: Collected amount D (g) = 300 ÷ X Place the macerating liquid D (g) containing 3 g of bone-dry pulp into a 1000 mL measuring cylinder and dilute it to 1000 mL to prepare a measuring liquid with a solids concentration of 0.3 mass %. Measure the temperature at this time with an accuracy of 1°C.

[0028] The adjusted test solution is then measured using the Canadian Standard Freeness Tester described above. When pouring the test solution into the tester, the opening of the measuring cylinder is covered with the palm of the hand and the cylinder is inverted three times to agitate. Five seconds after pouring the test solution, the filtered water is allowed to drain. When the drainage from the side pipe stops, the mass of the drained water from the side pipe is weighed to an accuracy of 0.1 g, and the mass is converted to volume (mL). Next, the measured value is corrected to the freeness at a standard temperature of 20°C using the "Freeness Correction Table for a Temperature of 20°C" in Appendix D of JIS P 8121-2 2012 and the water temperature of the test solution. The average of these values ​​corrected to a temperature of 20°C is taken as the maceration freeness. The accuracy is 1 mL. If the concentration is not exactly 0.3% by mass, the concentration is corrected using the "Freeness Correction Table for a Concentration of 0.30%" in Appendix C of JIS P 8121-2 2012.

[0029] On the other hand, the fibers constituting the toilet paper according to this embodiment are not necessarily limited, but it is preferable that 60% to 85% by mass of the fibers constituting the toilet paper are pulp derived from hardwood. It is particularly preferable that 65% to 80% are pulp derived from hardwood. Hardwood-derived pulp has short fiber length, which makes it easy to improve the texture of the paper surface. On the other hand, hardwood-derived pulp is less likely to lose absorbency and firmness due to its short fiber length. However, the toilet paper according to this embodiment sufficiently exhibits firmness and absorbency by low beating so that the disaggregated freeness is slightly higher. Known hardwood-derived pulp includes LBKP (hardwood kraft pulp), LUKP, and LOKP, but bleached LBKP is preferable. As for fibers other than hardwood-derived pulp, softwood pulp is preferable. In this case, chlorine-bleached softwood kraft pulp (NBKP) is preferable.

[0030] Here, the tensile strength of the toilet paper according to this embodiment is a dry tensile strength in the machine direction of 250 cN / 25 mm or more and 360 cN / 25 mm or less, and a dry tensile strength in the cross direction of 65 cN / 25 mm or more and 120 cN / 25 mm or less. The dry tensile strengths in both the machine direction and the cross direction according to the present invention are in a low range for a nested type of lamination technology. In particular, the dry tensile strength in the cross direction is in a range that can be said to be equivalent to or lower than that of a regular product that does not use lamination technology. The low dry tensile strength in the machine direction improves the smoothness of the feel, and the low dry tensile strength in the cross direction improves softness. Furthermore, the wet tensile strength in the machine direction is 40 cN / 25 mm or more and 80 cN / 25 mm or less, and the wet tensile strength in the cross direction is 16 cN / 25 mm or more and 35 cN / 25 mm or less. The wet tensile strength in the cross direction is slightly higher than that of products that do not use lamination technology. This range can be achieved by adjusting the J / W ratio and sizing during base paper production.

[0031] Furthermore, the ratio of the dry tensile strength in the machine direction to the dry tensile strength in the cross direction of the toilet paper according to this embodiment (dry tensile strength in the machine direction / dry tensile strength in the cross direction) is 2.9 or more and 3.8 or less. Preferably, it is 3.0 or more and 3.7 or less. Here, the machine direction is also called the MD direction, and is the direction of flow during papermaking. The cross direction of the paper is also called the CD direction, and is the direction perpendicular to the direction of flow (MD direction) during papermaking. The aspect ratio of the toilet paper according to this embodiment is higher than that of regular products and is closer to that of products for shower toilets. This aspect ratio can be adjusted by the J / W ratio during base paper production. It is presumed that this aspect ratio will improve the stretchability of the sheet, particularly as described below.

[0032] In addition, the toilet paper according to this embodiment has a ratio of wet tensile strength in the transverse direction to dry tensile strength in the transverse direction (wet tensile strength in the transverse direction / dry tensile strength in the transverse direction) of 0.20 to 0.40. Preferably, it is 0.21 to 0.35. The tensile strength of toilet paper is generally lower in the transverse direction than in the longitudinal direction, and the inventors have discovered that this difference in low tensile strength in the transverse direction between dry and wet states can affect how people feel when wiping away moisture. In other words, a smaller difference in tensile strength between dry and wet states in the transverse direction makes it easier to obtain a sense of firmness and security when wiping away moisture. For this reason, for example, when used in a toilet with a flushing function, this can affect the sense of security when wiping away moisture that has adhered to the skin during flushing. The ratio of wet tensile strength in the longitudinal direction to dry tensile strength in the longitudinal direction (wet tensile strength in the transverse direction / dry tensile strength in the transverse direction) is preferably 0.10 to 0.25. The values ​​are equivalent to those of conventional regular products and products for shower toilets, and the longitudinal strength is reduced as usual, so there is little impact on the sense of firmness and security that is thought to be caused by the ratio of the wet tensile strength in the transverse direction to the dry tensile strength in the transverse direction (wet tensile strength in the transverse direction / dry tensile strength in the transverse direction). In the toilet paper of this embodiment, the ratio of the wet tensile strength in the transverse direction to the dry tensile strength in the transverse direction (wet tensile strength in the transverse direction / dry tensile strength in the transverse direction) and the ratio of the wet tensile strength in the longitudinal direction to the dry tensile strength in the longitudinal direction (wet tensile strength in the longitudinal direction / dry tensile strength in the longitudinal direction) can be adjusted by the J / W ratio during papermaking. However, in this case, the longitudinal tensile strength is adjusted to be slightly higher and the transverse tensile strength to be slightly lower. By adjusting this, the range of disintegration freeness, and further by the laminate embossing process described below, the ratio of the wet tensile strength in the transverse direction to the dry tensile strength in the transverse direction (wet tensile strength in the transverse direction / dry tensile strength in the transverse direction) can be suitably adjusted within the above range.

[0033] Dry tensile strength is a value measured based on JIS P 8113 (2006) and is measured as follows. Test specimens are cut to approximately 25 mm (±0.5 mm) wide x 150 mm long in both the longitudinal and transverse directions. Test specimens are measured as multi-ply. The tester used is a Minebea Co., Ltd. load cell tensile tester TG-200N or an equivalent. The grip spacing is 100 mm, and the tensile speed is set to 100 mm / min for longitudinal measurements and 50 mm / min for transverse measurements. Measurements are performed by clamping both ends of the test specimen into the grips of the tester, applying a tensile load in the vertical direction to the paper piece, and reading the indicated value (digital value) when the paper breaks. Five sets of samples are prepared in both the longitudinal and transverse directions, and measurements are performed five times each. The average of these measurements is taken as the dry tensile strength in each direction.

[0034] Wet tensile strength is a value measured based on JIS P 8135 (1998) and is measured as follows. Test pieces are cut to approximately 25 mm (±0.5 mm) wide x 150 mm long in both the longitudinal and transverse directions. For multi-ply toilet paper, the multi-ply paper is measured as is. The tester used is a Minebea Co., Ltd. load cell tensile tester TG-200N or an equivalent. The grip spacing is set to 100 mm, and the tensile speed is set to 50 mm / min. Test pieces are cured for 10 minutes in a dryer at 105°C. After clamping both ends of the test piece into the grips of the tester, water is applied horizontally to the center of the test piece over a width of approximately 10 mm using a water-soaked flat brush. A tensile load is then immediately applied in the vertical direction to the paper piece, and the reading (digital value) is read when the paper breaks. Five sets of samples are prepared in each of the machine direction and the cross direction, and measurements are made five times in each direction, and the average of the measurements is taken as the wet tensile strength in each direction.

[0035] On the other hand, the toilet paper according to this embodiment may contain known dry strength agents, dry strength agents, and temporary wet strength agents. However, because strength agents can particularly reduce softness and water disintegrability, it is preferable that these strength agents are not added. Therefore, it is preferable that the toilet paper according to this embodiment does not contain at least one, preferably two, and particularly all, of the dry strength agents, dry strength agents, and temporary wet strength agents. The toilet paper according to this embodiment can be a toilet roll with sufficient quality and functionality without using a strength agent, based on the essential components of the present invention, such as maceration freeness, tensile strength, and laminate embossing, and the technical common sense of a person skilled in the art.

[0036] Furthermore, the toilet paper of this embodiment preferably contains a softener. Examples of softeners include fatty acid ester-based softeners and cationic fatty acid amide-based softeners. The fatty acid ester-based softener may be either a cationic fatty acid ester-based compound or a nonionic fatty acid ester-based compound, and multiple types may be added. Examples of cationic fatty acid amide-based softeners include the reaction product of epihalohydrin with an amide compound obtained by reacting polyalkylene polyamines with monocarboxylic acids. The content of the softener is not necessarily limited, but is preferably 0.5 to 4.0 kg / t of pulp.

[0037] On the other hand, the toilet paper of this embodiment has the above-mentioned paper quality, and as a mechanical structure, as shown in Figures 2 and 3, in particular, each of the first sheet 11 and second sheet 12 constituting the toilet paper 10 is embossed to form recesses 32 on one side and protrusions 31 corresponding to the recesses 32 on the other side, and in particular, these sheets are stacked so that the surfaces with the protrusions face each other, and are bonded together by adhesive at the tops of the protrusions 31. Therefore, the toilet paper according to this embodiment has a configuration in which only the recesses 32 are present on the front and back surfaces.

[0038] The planar shape of each recess 32 is not limited. In addition, they do not all need to be the same shape. A suitable shape for the recess 32 is one without corners in terms of softness and other touches, and specifically, a circle, an ellipse, a rounded triangle, a rounded rectangle, or a rounded polygon is preferred. A circle or an ellipse is particularly preferred. The area of ​​the recess 32 is 0.5 to 8 mm ２ is preferable, and 1.0 to 3.2 mm ２ is particularly preferred.

[0039] The embossed area ratio (total area of ​​recesses / total area of ​​sheets) in the toilet paper 10 of this embodiment is not necessarily limited, but is preferably 15 to 28%. On each side of the first sheet and the second sheet, it is preferably 8 to 14%. Here, the embossed area ratio in the toilet paper of this embodiment is a value measured on a sample taken 30 cm from the end of the winding, excluding the tail seal portion.

[0040] The arrangement (embossing pattern) of the recesses 32 in the toilet paper 10 of this embodiment is not limited. As one form, an arrangement in which the recesses 32 are appropriately arranged to form an appropriate geometric pattern such as a floral pattern or a heart pattern as a whole, as shown in Figure 3, is desirable from the standpoint of design.

[0041] Here, the stacking configuration of the first sheet 11 and the second sheet 12 in the toilet paper 10 of this embodiment can be a so-called tip-to-tip configuration in which the convex portions of the first sheet face the convex portions of the second sheet, or a so-called nested configuration in which the convex portions 31 of the first sheet 11 face the portions of the second sheet 12 other than the convex portions 31, as shown in FIG. 2, and the convex portions 31 of the second sheet 12 face the portions of the first sheet 11 other than the convex portions 31. The nested configuration is particularly preferred. The nested configuration facilitates the development of soft toilet paper due to the different positions of the concave portions on the front and back. Furthermore, the number of columnar convex portions 31 between the sheets is increased, making it difficult for the gaps between the sheets to collapse, thereby improving wiping performance, absorbency, and a sense of security when wiping. Furthermore, the thickness can be made thinner than the tip-to-tip configuration. For this reason, in a rolled form such as toilet rolls, where a specified length needs to be contained within a specified roll diameter, each sheet can be made to have a higher basis weight and lower density than tip-to-tip toilet paper, and can be wound up somewhat looser, so the unevenness caused by the embossing is less likely to be crushed, making it particularly excellent in terms of both quality and functionality.

[0042] Furthermore, the first sheet 11 and the second sheet 12 in the toilet paper 10 of this embodiment may be bonded at all of the protruding portions 31, but are not necessarily bonded at all of the protruding portions 31. In one preferred embodiment, no adhesive is applied to the protruding portions 31 of the second sheet 12 located on the inner winding surface of the roll, and the first sheet 11 and the second sheet 12 are bonded together by adhesive applied to all or some of the protruding portions 31 of the first sheet 11 located on the outer winding surface of the roll. A toilet roll of this embodiment has no adhesive portions near the outer winding surface of the roll, so it is easy to feel a softness, especially when holding the roll in your hand.

[0043] Furthermore, the adhesive area ratio (total area of ​​adhesive portions / total area of ​​sheet) in the toilet paper 10 of this embodiment is not necessarily limited, but is preferably 20% or less. The lower limit is particularly preferably 9%. If the adhesive area ratio is 20% or less, the hard texture of the toilet paper, particularly that achieved by the laminate embossing technique, becomes less noticeable. Note that the adhesive area ratio in the toilet paper of this embodiment is a value measured using a sample taken 30 cm from the end of the roll, excluding the tail seal portion.

[0044] The type of adhesive used in the toilet paper of this embodiment is not necessarily limited. Preferred adhesives are water-soluble adhesives such as PVA (polyvinyl alcohol) and CMC (carboxymethyl cellulose), and CMC, which is a cellulose-based water-soluble adhesive, is particularly preferred.

[0045] Here, in the configuration of the toilet paper according to this embodiment, four sheets are stacked and the compressibility is 0.5 gf / cm when the measuring terminal is pressed into the compression tester. ２ Load T0 to 50gf / cm ２ The stretchability, which is the displacement (T0-Tm) up to Tm under load, can be set to 1.0 mm or more. Therefore, it is preferable that the toilet paper of this embodiment has this stretchability of 1.0 mm or more. The stretchability can be measured using a KES-G5 (manufactured by Kato Tech Co., Ltd.) or an equivalent device. The measurement terminal is the standard terminal 2 cm attached to the KES-G5. ２ Or equivalent measuring terminal (circular, measuring surface flat, area 2 cm ２ More specifically, as shown in FIG. 4, four sheets of toilet paper 10 are stacked and placed on the measurement table of the compression tester or on a hard horizontal table 40, and the measurement surface is placed on the toilet paper to a size of 2 cm. ２ The flat surface of the measuring terminal is pressed against the surface at a speed of 0.02 mm / sec. ２ The indentation position T0 under load and 50 gf / cm ２The indentation position Tm when the load is applied is measured, and the difference is taken as the stretchability value. The sample is the paper width (roll width) x 100 mm. Stretchability particularly affects quality aspects such as softness and fluffiness in the thickness direction. For shower toilet products, emphasis is placed on ensuring gaps between sheets using laminate embossing technology, so stretchability is generally around 0.5 to 0.7 mm. Stretchability exceeding 1.0 mm is equivalent to or better than that of standard products. As described above, the toilet paper configuration of the present invention can achieve a stretchability of 1.0 mm or more. In particular, adjusting at least one of the embossing-related configurations, such as the lamination configuration, embossed area ratio, adhesive area ratio, and adhesive type, within the above ranges makes it easier to achieve this stretchability value. Furthermore, to measure the stretchability of the toilet paper of this embodiment, a sample is taken from a position 1 to 15% from the end of the toilet roll. If the stretchability at this position is within the above range, the unevenness caused by the embossing will not be crushed, and the quality will be fully satisfactory.

[0046] In addition, the toilet paper according to this embodiment has a standard terminal of 2 cm. ２ The compression characteristic LC value, which can be measured simultaneously with or separately from the stretchability using a machine such as the KES-G5 (manufactured by Kato Tech Co., Ltd.) or its equivalent, is preferably in the range of 0.35 to 0.70, the compression energy WC value is preferably in the range of 1.25 to 1.75, and the recoverability RC value is preferably in the range of 40 to 50. These values ​​are equivalent to or greater than those of standard products and shower toilet products. The closer the compression characteristic LC value to 1.0, the harder the product is when compressed; the larger the compression energy WC value, the easier it is to compress; and the closer the recoverability RC value to 100, the better the recoverability.

[0047] On the other hand, the toilet paper according to this embodiment preferably has an HF (hand feel) value of 94 or more, as measured by a tissue softness measuring device (TSA). With the configuration of the toilet paper according to this embodiment, the HF (hand feel) value can be 94 or more. An HF (hand feel) value of 94 or more is a high value that is equal to or higher than that of standard products. The HF (hand feel) value is measured on the outer surface of the roll. The measurement sample is taken from a position 1 to 15% from the end of the toilet roll.

[0048] The tissue softness measuring device TSA is a tissue softness measuring device TSA manufactured by Emtec Electronic GmbH (Japan distributor: Nippon Luft Co., Ltd.) in Germany, and its equivalents. The feel of toilet paper when used is affected by the properties of the toilet paper, such as "smoothness / roughness," "softness," and "stiffness." This tissue softness measuring device TSA is capable of quantifying parameters that serve as indicators of these three properties (represented by TS750, TS7, and D, respectively) through acoustic and deformation measurements. The tissue softness measuring device TSA can then calculate the HF (hand feel) value by performing analysis using a nonlinear algorithm based on these obtained parameters (raw data) and the toilet paper's basis weight, thickness, number of plies, etc. The algorithm for calculating the HF value in this invention and this embodiment is TPII. The HF value is a value used for comprehensive quantitative evaluation of the feel of toilet paper, correlated with the results of human touch (panel test). For measurements using the tissue softness measuring device TSA according to this embodiment, a sample was cut into a circle with a diameter of approximately 112.8 mm using a sample punch manufactured by Emtec Corporation, and the software used for analysis and quantification was the Emtec Measurement System.

[0049] The TS750 value, TS7 value, and D value, which are data on the HF (hand feel) value of the toilet paper according to this embodiment, are not necessarily limited, but the TS750 value is 20 to 35 dBV. ２rms is preferred. TS750 is the intensity of the first maximum peak in the spectrum seen from the low frequency side, obtained when a bladed rotor is pressed from above onto toilet paper placed on a sample stage with a pressing pressure of 100 mN, then rotated at a rotation speed of 2.0 per second, and the vibration of the sample stage is measured with a vibration sensor, and is a parameter that is affected by "smoothness / roughness." The smaller the TS750 value, the better the "smoothness."

[0050] In addition, the TS7 value of the toilet paper according to this embodiment is 7.0 to 10.0 dBV. ２ rms is preferred. The TS7 value is the intensity of the maximum peak in the spectrum containing a frequency of 6500 Hz, which is obtained when a bladed rotor is pressed from above onto toilet paper placed on a sample stage with a pressing pressure of 100 mN, then rotated at a rotation speed of 2.0 per second, and the vibration of the sample stage is measured with a vibration sensor, and is a parameter that is mainly affected by "softness" in terms of fluffiness, surface softness, and bulk softness. The smaller the TS7 value, the better the "softness".

[0051] Furthermore, the value of D for the toilet paper according to this embodiment is preferably 3.5 to 4.0 mm / N. The value of D is expressed as the amount of deformation displacement of the sample in the up-and-down direction between the indentation pressures of 100 mN and 600 mN when the bladed rotor of the measuring device is pressed from above onto the sample set on the sample stage without rotating, and is a parameter that is affected by rigidity.

[0052] On the other hand, the water absorption capacity of the toilet paper according to this embodiment is preferably 0.60 or more. The water absorption capacity here is measured by using a stack of 20 sheets of toilet paper as a sample, dripping water at a constant rate onto a single point on the sample, and measuring the amount of water dripped when the water penetrates to the opposite side of the sample. The test method is as follows: 10 sheets of toilet paper are stacked and fixed in a stacked state using a sample holder (jig). A water detection device is placed below the sample in a position that contacts the sample. Water is dripped at a rate of 10±2 mL / min onto the same point on one side of the sample from a position 10 mm above the upper part of the sample exposed through a circular opening of φ21 mm in the center of the jig, and the amount of water dripped when the water penetrates the sample and the detection device detects water is recorded as the water absorption capacity.

[0053] On the other hand, the water disintegrability of toilet paper is specified as within 100 seconds in the unraveling test of JIS P 4501 (1993), but the configuration of the toilet paper according to the embodiment can be within 25 seconds, particularly within 20 seconds. This is a very high water disintegrability compared to products for shower toilets. From this perspective, the water disintegrability of the toilet paper of the embodiment is preferably within 25 seconds, and more preferably 20 seconds or less. In the unraveling test of JIS P 4501 (1993), the test specimen used in the test is 114±2 mm square, based on the toilet roll paper width of 114 mm. However, if the roll width of the toilet roll of the embodiment is 114 mm or less, the test specimen should be 114 mm x 114 mm.

[0054] Furthermore, the toilet paper according to this embodiment preferably has an MMD of 11.0 or less. Using the laminate embossing technique to achieve an MMD of 11.0 or less results in a less hard feel to the touch. The MMD is measured using a measuring device 100 shown in FIG. 5 , in which the contact surface of a friction element is brought into contact with the surface of a measurement sample to which a tension of 20 g / cm is applied in a predetermined direction at a contact pressure of 25 g, and the friction element is moved 2 cm in approximately the same direction as the tension at a speed of 0.1 cm / s. The coefficient of friction at this time is measured using a friction feel tester KES-SE (manufactured by Kato Tech Co., Ltd.) or an equivalent device. The MMD is the value obtained by dividing the coefficient of friction by the friction distance (movement distance = 2 cm). The friction element is made of 20 adjacent piano wires P with a diameter of 0.5 mm, and has a contact surface formed so that both the length and width are 10 mm. The contact surface is formed with unit bulges, the tips of which are made of 20 piano wires P (with a curvature radius of 0.25 mm).

[0055] Furthermore, the toilet paper of this embodiment preferably has a softness of 3.0 cN / 100 mm or less, particularly preferably 2.8 to 1.0 cN / 100 mm. This softness is measured based on the handle-o-meter method in accordance with JIS L 1096 (2010) Method E.

[0056] In the toilet paper of this embodiment, if the MMD and softness are within the above ranges, it can be said that the quality aspects such as surface texture and softness are within a range that satisfies consumers.

[0057] On the other hand, the toilet roll of this embodiment has a winding density of 0.85 or less, preferably 0.85 to 0.70, and particularly preferably 0.80 to 0.72. By setting the winding density within this range, the recesses and protrusions created by the embossing process are less likely to be crushed, making it easier to achieve both quality and functionality. The winding density is calculated by (paper thickness x winding length x number of plies) ÷ (cross-sectional area of ​​the roll). The cross-sectional area of ​​the roll is also calculated by {cross-sectional area of ​​the roll's winding diameter (outer diameter) L1 portion} - (cross-sectional area of ​​the cardboard tube's outer diameter L3 portion).

[0058] On the other hand, the toilet roll of this embodiment preferably has a winding hardness of 0.40 to 0.70 kgf. The winding hardness is measured by wrapping a diameter rule (manufactured by Muratec KDS Co., Ltd.) or its equivalent around the toilet roll in the circumferential direction at the center between the end faces, and measuring the force required to pull the Π rule scale by three graduations using a push-pull gauge (manufactured by Imada Co., Ltd.) or its equivalent. The winding hardness affects the feel of the roll when held in the hand and the ease with which the toilet paper constituting the roll deforms. A winding hardness in the range of 0.40 to 0.70 kgf is comparable to that of regular products and lower than that of products for shower toilets. This preferred form of toilet roll is wound in a state in which the unevenness caused by the embossing is adequately maintained within the roll, and there is room for the unevenness to be crushed and the toilet paper to be deformed by a load equivalent to that of regular products. On the other hand, the sheets are not stiff, and the unevenness caused by the laminate embossing using adhesive is not excessively crushed when they are rolled up. This gives the impression of being close to a regular product in terms of quality.

[0059] On the other hand, the toilet roll of this embodiment preferably has a roll winding hardness of 2.0 mm or more and 5.0 mm or less, and particularly preferably 2.1 mm or more and 4.5 mm or less. The roll winding hardness is also preferably 7.0 mm or more and 13.0 mm or less, and particularly preferably 7.2 mm or more and 12.5 mm or less. Furthermore, the roll softness is preferably 4.0 mm or more and 10.0 mm or less, and particularly preferably 4.5 mm or more and 9.5 mm or less. With the toilet roll of this embodiment having the above-mentioned winding length, roll diameter, and toilet paper configuration, the roll winding hardness, roll winding hardness, and roll softness can be adjusted within the above ranges by adjusting the winding speed and winding tension during production.

[0060] Here, the roll winding hardness of the toilet roll of this embodiment is, as shown in FIG. 6, 0.5 gf / cm when a measuring terminal of a compression tester is pressed into the widthwise center of the peripheral surface of the toilet roll 1. ２ Load T0 to 500gf / cm ２It is the displacement (T0-Tm) up to Tm when a load is applied. The roll tightness can be measured using a KES-G5 (manufactured by Kato Tech Co., Ltd.) or an equivalent device. The measurement terminal is the standard terminal 2 cm attached to the KES-G5. ２ Or equivalent measuring terminal (circular, measuring surface flat, area 2 cm ２ More specifically, as shown in FIG. 6, the toilet roll 1 is placed on the measurement table of the compression tester or on a hard horizontal table 40 with the axis in the horizontal direction, and the measurement surface is measured from above in the radial direction at the center of the width of the toilet roll 1. ２ The flat surface of the measuring terminal 41 is pressed against the surface at a speed of 0.02 cm / sec. ２ The indentation position T0 under load and 500 gf / cm ２ The pressing position Tm when the load is applied is measured, and the difference is taken as the value of the roll winding hardness.

[0061] The roll winding hardness of the toilet roll 1 of this embodiment was measured in the same manner as the roll winding hardness described above, with an acrylic plate 42 of 2 mm thickness, 80 mm x 140 mm, and 26.5 ± 0.2 g interposed between the toilet roll 1 and the measuring terminal 41, as shown in Figure 7, and was 0.5 gf / cm ２ Load T0 to 500gf / cm ２ The displacement is the amount of displacement (T0-Tm) up to Tm when the load is applied, where the moving speed of the measuring probe is 0.01 cm / sec.

[0062] The roll softness of the toilet roll of this embodiment is the amount of displacement when pressed, as shown in Figure 8, by inserting an acrylic core 43 of which the inner diameter is ±2 mm of the paper core into the paper core of the toilet roll, and measuring it in the same way as the roll winding hardness described above, except that the amount of displacement is 0.5 gf / cm ２ Load T0 to 150 gf / cm ２ The displacement up to the load Tm is defined as (T0-Tm). The moving speed of the measuring probe is set to 0.02 cm / sec.

[0063] Here, roll winding hardness can be said to be the ease with which a roll deforms when pressed locally in a narrow area on the circumferential surface of the roll, while roll winding hardness can be said to be the ease with which a roll deforms when pressed widely across the entire circumferential surface of the roll. Furthermore, roll softness can be said to be the softness of the wound portion of the roll. These roll winding hardness, roll winding hardness, and roll softness can be said to be indicators of the deformability of the roll and the state of the toilet paper in roll form. In particular, if they are within the above ranges, it can be said that the unevenness caused by the embossing process is not crushed or is within an appropriate range, the effects of the paper quality due to the toilet paper's disaggregation freeness and tensile strength configuration, etc., are not reduced, and the toilet paper is wound in a sheet state that is fully satisfactory in terms of quality and functionality. The roll winding hardness, roll winding hardness, and roll softness can be easily adjusted to these numerical ranges by adjusting at least one of the embossing-related configurations, such as the lamination configuration, embossed area ratio, adhesive area ratio, and adhesive type, within the above ranges.

[0064] Next, the physical properties of the examples, comparative examples, and conventional examples of the toilet rolls according to the present invention were measured. The results are shown in Table 1, and the measurement methods for each physical property and characteristic were as described above. The embossed unevenness was the pattern shown in Figure 3, except for commercially available conventional examples 1 to 5. The lamination configuration was nested in each example and comparative example 1. Comparative example 2 and conventional example 2 were tip-to-tip. Conventional examples 3 and 4 were single-embossed. Conventional examples 1 and 5 were non-laminated embossed, and although they were double-embossed with raised portions facing each other, they were integrated by edge embossing, and the positions of the raised portions were not specified. The embossed area ratio in the examples and comparative examples was approximately 10% on both the front and back sides, totaling approximately 20%. The adhesive area ratio was 10%. Furthermore, the toilet paper according to the examples and comparative examples did not contain a dry strength agent, wet strength agent, or temporary wet strength agent. The softener was used in the same blending ratio in both the examples and the comparative examples. Furthermore, CMC (carboxymethyl cellulose) was used as the adhesive in both the examples and the comparative examples.

[0065] Conventional example 1 is a toilet roll from a product group known as a standard product, while conventional examples 2 and 5 are products with low basis weights even within the shower toilet product group. In other words, they are products with a basis weight that is the same as or lower than standard products in order to achieve softness, etc. Conventional example 3 is a product from the shower toilet product group that uses single embossing, and conventional example 4 is a product from the general shower toilet product group.

[0066]

[0067] As shown in Table 1, the toilet rolls according to each Example achieved softness and HF (hand feel) values ​​equivalent to or greater than those of Conventional Example 1, a conventional standard product, and were comparable in quality to the standard product. These values ​​were significantly higher than Conventional Examples 2 to 4, which are products for shower toilets. Furthermore, the strengths, such as wet tensile strength, were significantly higher than Conventional Example 1, which is a standard product, and close to Conventional Examples 2 to 4, which are products for shower toilets, and higher than Conventional Example 5. The stretchability value of Comparative Example 1 was outside the range of the Examples, likely due to the aspect ratio, and the HF (hand feel) value was similar to that of the shower toilet products, and was not sufficiently improved. The TS7, TS750, and D values ​​also indicate that the Examples possessed the softness and fluffiness of standard products, as well as the firmness of paper used for shower toilets. In other words, the examples of the present invention combine the quality aspects of texture, such as the softness and fluffiness of regular products, with functionality, such as the firmness and absorbency of paper used in shower toilets, making them toilet rolls that are unlikely to cause dissatisfaction whether used normally or in toilets with a flushing function.

[0068] 1...toilet roll, 10...toilet paper, 11...first sheet, 12...second sheet, 20...paper tube (tube core), 31...convex portion, 32...concave portion, 40...horizontal stand (measuring stand), 41...measuring terminal, 42...acrylic plate, 43...acrylic core, L1...toilet roll reel diameter (diameter), L3...diameter of toilet roll tube core, L2...toilet roll width.

Claims

1. A toilet roll in which two sheets are laminated together to form a two-ply toilet paper roll with a roll length of 20 to 40 m and a roll diameter of 110 to 130 mm, wound around a paper tube; the toilet paper is made of sheets that have embossed depressions on one side and protrusions corresponding to the depressions on the other side, laminated so that the convex surfaces face each other and are bonded together at the tops of the protrusions with adhesive; the dry tensile strength in the machine direction is 250 cN / 25 mm or more and 360 cN / 25 mm or less, and the dry tensile strength in the cross direction is 65 cN / 25 mm or more and 120 cN / 25 mm or less; the ratio of the dry tensile strength in the machine direction to the dry tensile strength in the cross direction (dry tensile strength in the machine direction / dry tensile strength in the cross direction) is 2.9 or more and 3.8 or less; A toilet roll characterized in that the wet tensile strength in the longitudinal direction is 40 cN / 25 mm or more and 80 cN / 25 mm or less, the wet tensile strength in the transverse direction is 16 cN / 25 mm or more and 35 cN / 25 mm or less, and the ratio of the wet tensile strength in the transverse direction to the dry tensile strength in the transverse direction (wet tensile strength in the transverse direction / dry tensile strength in the transverse direction) is 0.20 to 0.

40.

2. The toilet roll according to claim 1, wherein the ratio of the wet tensile strength in the machine direction to the dry tensile strength in the machine direction (wet tensile strength in the machine direction / dry tensile strength in the machine direction) is 0.10 to 0.25.

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