Moisturized sanitary paper, toilet roll and moisturized sanitary paper housing

Abstract

To provide a moisturized sanitary paper having excellent quality (softness) even with a reduced additional amount of moisture-retaining component.SOLUTION: A moisturized sanitary two-ply paper laminating a first ply and a second ply contains moisturizer. In the moisturized sanitary paper, content of the moisturizer is 0.3 g / m2 or larger and below 3.2 g / m2 and, when content of the moisturizer of the first ply is P and content of the moisturizer of the second ply is Q, P>Q is satisfied and value of P / Q is 1.10≤P / Q≤1.35.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to moisturizing sanitary paper, toilet rolls, and moisturizing sanitary paper containers. [Background technology]

[0002] Tissue paper products are broadly divided into non-moisturizing tissue and moisturizing tissue. Moisturizing tissue is produced by applying a moisturizing agent such as glycerin to the tissue base paper after papermaking, while non-moisturizing tissue is a common tissue that does not have a moisturizing agent applied to the tissue base paper. Because tissue paper products come into direct contact with the skin, there is a tendency to prefer products that are less irritating to the skin, and in recent years, demand for moisturizing tissue has been increasing.

[0003] Moisture-retaining tissues are produced by applying a hygroscopic agent such as glycerin to a base paper of sanitary tissue. For example, Patent Document 1 discloses a technique for externally applying an oily substance and a moisturizing agent. This technique proposes that moisturizing components such as an oily substance and a moisturizing agent be added to the base paper of sanitary tissue to enhance water retention and moist feeling.

[0004] In addition to moisturizing tissue, toilet paper containing a moisturizing component is also known as a sanitary paper containing a moisturizing component. Patent Document 2 discloses a toilet paper roll that can be coated with a water-soluble moisturizing component and / or a water-soluble softening component on the entire surface of the sheet. This discloses a toilet paper roll containing a moisturizing agent by coating the entire surface with a water-soluble moisturizing component and a softening component on the toilet paper winding line (roll winder). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 4-9121 [Patent Document 2] International Publication No. 2012 / 105135 Summary of the Invention [Problem to be solved by the invention]

[0006] As described above, various types of sanitary paper containing moisturizing ingredients are known. However, there is room for improvement in the soft feel of conventional moisturizing sanitary paper. In particular, there is a need for improvement so that the soft feel can be maintained even when the amount of moisturizing ingredient added is reduced to reduce production costs.

[0007] Therefore, in order to solve these problems of the conventional technology, the inventors have conducted research with the aim of providing moisturizing sanitary paper that has excellent quality (softness) even when the amount of moisturizing ingredient added is reduced. [Means for solving the problem]

[0008] Examples of specific embodiments of the present invention are given below.

[0009] [1] A two-ply moisturizing sanitary paper in which a first ply and a second ply are laminated, Moisturizing sanitary paper contains a moisturizing agent, and the moisturizing agent content is 0.3g / m 2 More than 3.2g / m 2 is less than Moisture-retaining sanitary paper in which, when the content of moisturizing agent in the first ply is P and the content of moisturizing agent in the second ply is Q, P>Q and the value of P / Q is 1.10≦P / Q≦1.35. [2] A toilet roll made by winding the moisturizing sanitary paper described in [1] into a roll. [3] The toilet roll according to [2], wherein the first ply is disposed on the outer winding side of the roll. [4] A moisturizing sanitary paper container in which multiple sets of the moisturizing sanitary paper described in [1] are stacked and folded so as to pop up and stored in a package. [5] The moisturizing sanitary paper container according to [4], in which the first ply is arranged on the outside when the moisturizing sanitary paper is folded in a mountain fold. [Effects of the Invention]

[0010] According to the present invention, moisturizing sanitary paper having excellent quality (softness) can be obtained even when the amount of moisturizing component added is reduced. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram showing a moisturizing toilet roll according to one embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] The present invention will be described in detail below. The following description of the constituent elements may be based on representative embodiments or specific examples, but the present invention is not limited to such embodiments. In this specification, a numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the lower and upper limits.

[0013] (Moisturizing hygienic paper) This embodiment is a two-ply moisturizing sanitary paper in which a first ply and a second ply are laminated. The moisturizing sanitary paper contains a moisturizing agent, and the content of the moisturizing agent is 0.3 g / m 2 More than 3.2g / m 2 The present invention relates to moisturizing sanitary paper in which the moisture content is less than P, and where P is the moisture content of the first ply and Q is the moisture content of the second ply, P>Q and the value of P / Q is 1.10≦P / Q≦1.35.

[0014] Examples of the moisturizing sanitary paper of this embodiment include tissue paper, tissue paper, paper towels (such as kitchen paper), toilet paper, and watting (cotton paper). Of these, the moisturizing sanitary paper of this embodiment is preferably tissue paper or toilet paper. The sanitary paper of this embodiment is soft and has an excellent feel, making it suitable for use in applications where it comes into direct contact with the skin.

[0015] The humectant content is the total content of humectants in the moisturizing sanitary paper (first and second plies). The humectant content is 0.3 g / m 2 It is preferable that the content is 0.4 g / m or more. 2 It is more preferable that the content of the moisturizing agent is 3.2 g / m or more. 2 Preferably less than 3.1 g / m 2 More preferably, it is 3.0 g / m or less. 2 More preferably, it is 2.8 g / m or less. 2 More preferably, it is 2.4 g / m or less. 2 It is particularly preferable that: According to this embodiment, even when the content of the humectant is reduced, the moisturized sanitary paper has excellent quality (softness).

[0016] If the content of humectant in the first ply is P and the content of humectant in the second ply is Q, then it is preferable that P>Q. The P / Q value is preferably 1.10 or greater, more preferably 1.12 or greater, and even more preferably 1.15 or greater. The P / Q value is preferably 1.35 or less, more preferably 1.32 or less, even more preferably 1.30 or less, and particularly preferably 1.25 or less. By keeping the P / Q value within the above range, excellent quality (softness) can be exhibited even when the amount of humectant added to moisturizing sanitary paper is reduced.

[0017] The amount of humectant contained in the moisturizing sanitary paper (first and second plies) (g / m 2 ) can be calculated from the amount of humectant applied during the manufacture of moisturizing sanitary paper, but if the moisturizing sanitary paper is a pre-made product, an arbitrary area (for example, 10 sheets of 0.1m x 0.1m) can be sampled in an environment conforming to ISO187 (temperature 23±1°C, relative humidity 50±2%), and the humectant content can be calculated using the following formula from the mass of humectant extract obtained, for example, by the Soxhlet extraction method. With the Soxhlet extraction method, the solid content contained in the moisturizing sanitary paper is extracted under reflux with acetone / ethanol (1:1) for 4 hours, and the humectant content is calculated using the following formula. Moisturizing agent content (g / m 2 ) = mass of extract (g) / sample size (m 2 )

[0018] The affected moisture content of moisturizing sanitary paper is preferably 0.3% by mass or more, more preferably 0.5% by mass or more, and even more preferably 0.7% by mass or more. The affected moisture content of moisturizing sanitary paper is preferably 3.5% by mass or less, and more preferably 3.4% by mass or less. In this specification, the affected moisture content is a value calculated using the following formula: Influence of moisture (mass%) = Moisture applied to moisturizing sanitary paper (mass%) - 0.15 x Moisturizer applied to moisturizing sanitary paper (mass%) By setting the moisture content of the moisturizing sanitary paper within the above range, the quality (softness) of the moisturizing sanitary paper can be improved more effectively, and the productivity of the moisturizing sanitary paper can also be increased.

[0019] The paper thickness (total thickness) of the moisturizing sanitary paper is preferably 20 μm or more, more preferably 25 μm or more, and even more preferably 30 μm or more. The paper thickness (total thickness) of the moisturizing sanitary paper is preferably 250 μm or less, more preferably 220 μm or less, and even more preferably 200 μm or less. By maintaining the paper thickness within the above range, the feel of the moisturizing sanitary paper during use can be improved and sufficient strength can be obtained. Furthermore, by maintaining the paper thickness within the above range, the stiffness during use can be reduced and the feel can be improved. The paper thickness (total thickness) of the moisturizing sanitary paper is the measured value for a two-ply moisturizing sanitary paper. A thickness gauge (manufactured by Hybridge Manufacturing Co., Ltd.) can be used for measurement. The total thickness is measured at a measuring pressure of 50 kPa and when the probe is lowered at a speed of 1 mm per second or less. When the moisturizing sanitary paper is tissue, 10 sets of paper thickness measurements are prepared, and measurements are taken at three locations per set, and the thicknesses at a total of 30 locations are averaged. If the moisturizing sanitary paper is a roll product, take 30cm wide samples (so that the above three positions are in the center of the width) at three positions: 20% from the edge of the outermost roll, 50% from that edge along the roll length, and 20% from the edge of the innermost roll.Measure the paper thickness at 10 positions for each set, for a total of 30 positions, and calculate the average value.These measurements are carried out in an environment that complies with ISO187 (temperature 23±1°C, relative humidity 50±2%).

[0020] The basis weight of moisturizing sanitary paper is 8.0 g / m 2 It is preferable that the content is 9.0 g / m or more. 2 The basis weight of the moisturizing sanitary paper is more preferably 30.0 g / m or more. 2 Preferably, it is 25.0 g / m or less. 2 It is more preferable that the basis weight is less than 10 ...

[0021] The density of moisturizing sanitary paper is 0.12 g / cm 3 It is preferable that the concentration is 0.14 g / cm or more. 3 More preferably, it is 0.16 g / cm or more. 3 It is more preferable that the density of the moisturizing sanitary paper is 0.50 g / cm or more. 3 By setting the density within the above range, the smoothness of the surface of the moisturizing sanitary paper can be improved. 3 By setting the density as follows, it is possible to more effectively increase the permeability of the moisturizing solution, and to obtain moisturizing sanitary paper with an excellent feel. Furthermore, by setting the density within the above range, sufficient strength can be obtained while maintaining softness. The density of the moisturizing sanitary paper is the density of two-ply moisturizing sanitary paper, and is a value calculated by doubling the basis weight measured by the above-mentioned method and dividing by the paper thickness (two plies), as shown in the following formula. (Basis weight of 1 ply (g / m 2 ) × 2) / 2-ply paper thickness (μm) = density of moisturizing sanitary paper (g / cm 3 )

[0022] The hand feel value (hereinafter also referred to as HF value) of the surface of moisturizing sanitary paper is preferably 75.0 or higher, more preferably 76.0 or higher, and even more preferably 80.0 or higher. There is no particular upper limit, but it can be, for example, 100 or lower. By keeping the hand feel value within the above range, the smoothness and softness of the moisturizing sanitary paper can be increased, improving the feel to the touch. Here, the hand feel value (HF value) can be measured using a tissue softness analyzer (manufactured by Emtec Electronic GmbH) by the following measurement method. First, a sample cut into a circle with a diameter of 104.0 mm is placed on the sample stage of the tissue softness analyzer. If the sample is a two-ply product, use it as is. When cutting the sample into a circle, cut it so that the center of the circle is roughly located in the center of the tissue product. The bladed rotor is pressed from above onto this sample with a pressing pressure of 100 mN. The bladed rotor is then rotated at a speed of 2.0 revolutions per second, and the vibration frequency at that time is measured. In addition, the amount of deformation displacement in the vertical direction is calculated when a bladed rotor is pressed into another sample cut into a circle with a diameter of 104.0 mm with a pressure of 100 mN and 600 mN. The HF value is calculated from the vibration frequency and the amount of deformation displacement, and the Facial II calculation algorithm can be used. When calculating the HF value, prepare 10 sets of samples for each level. Use one set of 10 samples and measure the surface once. In this case, the surface refers to the surface facing outward of the product, and any surface facing outward can be measured. In the case of a single-ply product, the surface with the higher HF value is considered the surface. Measure all 10 sets of samples once, obtaining a total of 10 measurement data points, and calculate the average value. The above samples are measured in an environment that complies with ISO187 (temperature 23±1°C, relative humidity 50±2%). When measuring, the measurement is calibrated using a standard sample (emetec ref.2X(nn.n)) according to the attached instructions, and the algorithm is set to Facial II. The calculation software used is emetec measurement system ver.3.22.

[0023] This embodiment may relate to a toilet roll made by winding the above-mentioned moisturizing sanitary paper into a roll. As shown in Fig. 1, the toilet roll 100 is made by winding two sheets (two plies) of toilet paper (20a and 20b) into a roll of a predetermined length around a paper tube 1, which is a cylindrical core.

[0024] The roll density of toilet roll is 0.10 g / cm 3 It is preferable that the concentration is 0.13 g / cm or more. 3 More preferably, it is 0.15 g / cm or more. 3 It is more preferable that the winding density of the toilet roll is 0.35 g / cm or more. 3 Preferably, it is 0.30 g / cm or less. 3 More preferably, it is 0.25 g / cm or less. 3 More preferably, it is 0.20 g / cm or less. 3 By setting the winding density within the above range, the feel of the sanitary paper surface can be improved. 3 By setting the density to the above, when the moisturizing solution is applied to only one of the plies in the moisturizing solution application process, the penetration of the moisturizing solution into the non-coated side sheet that comes into contact with the coated side sheet and the uncoated surface of the laminated sheet is improved, and the chemicals are more likely to penetrate uniformly. 3 By doing so, it is possible to more effectively increase the permeability of the moisturizing solution and obtain moisturizing sanitary paper that has an excellent feel to the touch, which makes it easier to obtain moisturizing sanitary paper that maintains softness while having sufficient strength.

[0025] The winding density of the toilet roll is calculated using the following formula: The roll radius and core radius are calculated from their respective outer circumferences. Toilet roll density (g / cm 3 ) = Roll weight / (roll radius x roll radius x 3.14 x width - core radius x core radius x 3.14 x width) The roll weight is measured after conditioning for 24 hours in an environment conforming to ISO 187 (temperature 23±1°C, relative humidity 50±2%). Note that in the case of tissue products, where the sheets are not wound but are folded and stacked in a bundle, it is preferable to calculate the bundle density instead of the winding density. The bundle density is calculated using the following formula. Flux density (g / cm 3 ) = Bundle weight / (Bundle width x Bundle length x Bundle height) When measuring the stack height, the sheet stack is measured from the top of the stack to 16 g / m 2 The load is applied and the height of the four corners of the bundle is measured. The average value of the measurements (40 points) for a total of 10 bundles is taken as the bundle height.

[0026] FIG. 1 shows a toilet roll 100 made of rolled toilet paper, one embodiment of the present invention. The toilet paper 20 that makes up the toilet roll 100 is a two-ply toilet paper, consisting of an outer toilet paper 20a and an inner toilet paper 20b. In a preferred embodiment, moisturizing liquid is applied to both the outer toilet paper 20a and the inner toilet paper 20b. It is also preferable that the moisturizing liquid is applied to the surface where the outer toilet paper 20a and the inner toilet paper 20b come into contact (i.e., the surface that forms the inner surface of the two-ply sanitary paper). By making the coated surface the inner surface of the roll in this way, it is possible to prevent the moisturizing agent from falling off the roll product or adhering to other objects. Furthermore, by containing a large amount of moisturizing liquid in the outer toilet paper, the tactile sensation during use can be more effectively improved.

[0027] In this embodiment, the first ply is preferably disposed on the outer winding side of the roll. That is, in Fig. 1, the outer toilet paper 20a is preferably the first ply. This allows a soft feel to be more effectively achieved even when the amount of moisturizing agent added is reduced.

[0028] This embodiment may also relate to a moisture-retaining sanitary paper container in which multiple sets of the moisture-retaining sanitary paper described above are stacked and folded so as to pop up and housed in a package. The moisture-retaining sanitary paper container may be a portable type known as a pocket tissue, or a stationary type in which a stack of tissue paper is housed in a paper storage box or film known as a carton. This embodiment may also relate to an aggregate package in which multiple moisture-retaining sanitary paper containers housed in a carton or film are gusset-packaged together.

[0029] In the moisture-retaining sanitary paper container of this embodiment, the moisture-retaining sanitary paper is folded in a mountain fold to pop up and stored in the package, but when the moisture-retaining sanitary paper is folded in a mountain fold, it is preferable that the first ply be placed on the outside, which more effectively improves the tactile feel when the moisture-retaining sanitary paper is pulled out.

[0030] (Manufacturing method of moisturizing sanitary paper) The manufacturing process for the moisturizing sanitary paper described above includes a step of applying a moisturizing liquid to the sanitary paper base paper that forms the first and second plies. In the step of applying the moisturizing liquid, it is preferable that the moisturizing liquid is applied to the inner surfaces of the two plies of sanitary paper (sanitary paper base paper).

[0031] Sanitary paper base paper can be obtained by processing the pulp slurry using a known paper machine. Pulp components contained in the pulp slurry include wood pulp, non-wood pulp, and deinked pulp. Examples of wood pulp include hardwood pulp (hardwood kraft pulp (LKP)), softwood pulp (softwood kraft pulp (NKP)), sulfite pulp (SP), dissolving pulp (DP), soda pulp (AP), unbleached kraft pulp (UKP), and oxygen-bleached kraft pulp (OKP). Other examples include semi-chemical pulps such as semi-chemical pulp (SCP) and chemi-ground wood pulp (CGP), and mechanical pulps such as groundwood pulp (GP) and thermomechanical pulp (TMP, BCTMP). Examples of non-wood pulp include cotton pulps such as cotton linter and cotton lint, non-wood pulps such as hemp, straw, and bagasse, and cellulose, chitin, and chitosan isolated from sea squirts and seaweed. Examples of deinked pulp include deinked pulp made from recycled paper. The above pulps may be used alone or in combination of two or more.

[0032] The pulp component is preferably at least one selected from softwood pulp and hardwood pulp. In particular, in the present invention, it is preferable to use a combination of softwood pulp and hardwood pulp, and it is more preferable to use a combination of softwood kraft pulp (NKP) and hardwood kraft pulp (LKP).

[0033] Before the step of making paper from the pulp slurry, a step of bleaching the fiber raw material may be included. As the bleaching agent used in the bleaching step, known bleaching agents such as oxygen-based bleaching agents and chlorine-based bleaching agents can be used.

[0034] The step of preparing the pulp slurry preferably includes a step of beating the pulp components. In the beating step, for example, a double-disc refiner or the like can be used for beating treatment. During the beating treatment, for example, the softwood pulp and the hardwood pulp may be beaten separately, or they may be mixed and then beaten.

[0035] The pulp slurry may contain optional components in addition to the pulp component. Examples of optional components include dry strength agents, wet strength agents, and softeners. Examples of dry strength agents include cationized starch, polyacrylamide (PAM), and carboxymethyl cellulose (CMC). Examples of wet strength agents include polyamide epichlorohydrin, urea, melamine, and thermally crosslinkable polyacrylamide. Examples of softeners include anionic surfactants, nonionic surfactants, cationic surfactants, and zwitterionic surfactants.

[0036] Examples of paper machines for making paper from pulp slurry include suction breast formers (cylinder type, Fourdrinier type), twin wire formers, cylinder formers (C-wrap, S-wrap), and crescent formers.

[0037] A papermaking machine that produces pulp slurry generally includes a wire section, a press section, a dryer section, a calendar section, and a reel section. The wire section is a process for dehydrating the supplied slurry to form a sheet. In the wire section, the pulp slurry is supplied to a forming unit, which forms a two-layer sheet that will become the base paper for sanitary paper. In the forming unit, the component blend ratios of the pulp slurry that form each layer can be made different. This allows the properties of each layer that makes up the base paper for sanitary paper to be different.

[0038] In the process of making pulp slurry, it is preferable to adjust the ratio of the discharge water flow rate to the wire speed (jet wire ratio (J / W ratio)) so that the basis weight per ply of sanitary paper falls within a specified range and the strength of the sanitary paper falls within a desired range. The jet wire ratio is the ratio of the slurry supply rate to the wire running speed. When the jet wire ratio is greater than 1, the slurry supply rate is faster than the wire running speed, and this is called "push formation." When the jet wire ratio is 1 or less, the slurry supply rate is slower than the wire running speed, and this is called "pull formation." The jet wire ratio (J / W ratio) is preferably adjusted to, for example, 0.90 or more and 1.05 or less.

[0039] In the process of making paper from the pulp slurry, for example, a method of making paper from a pulp slurry that is a mixture of softwood pulp and hardwood pulp to form a single uniform layer of wet paper, or a method of making a softwood pulp layer and a hardwood pulp layer together to form a single sheet of wet paper, and either method may be adopted.

[0040] The press part of a papermaking machine is a process in which pressure is applied to the sheet to further dehydrate it. In the press part, pressure is applied to the sheet formed in the wire part to squeeze out moisture from the sheet. By applying pressure to the sheet in the press part, the surface of the sheet is made smooth and the density of the pulp component can also be adjusted.

[0041] In the dryer part, the sheet obtained through the press part is dried. The drying process is preferably, for example, a process of blowing hot air toward the wet paper or a process of pressing the wet paper against the outer surface of the Yankee dryer. In the drying process using the Yankee dryer, the dried paper can be scraped off from the Yankee dryer with a doctor blade (creping process) to form crepe-like wrinkles. In this case, the crepe ratio is preferably 10 to 40%. The crepe ratio is calculated by (Yankee dryer speed - reel speed) / reel speed x 100. By setting the crepe ratio within the above range, the softness and strength of the moisturizing sanitary paper can be effectively improved.

[0042] The manufacturing process of sanitary paper base paper may include a calendering step, which is carried out in a calendering part, in which the surface of the dried sheet is stretched while being pressed to make the surface of the sheet smooth.

[0043] In the reel part, the sanitary paper base paper obtained through the above steps is wound up to form a roll (base paper roll). At this time, it is preferable to wind the sheet (tissue paper) so that the surface pressed against the Yankee dryer becomes the outer peripheral surface of the base paper roll.

[0044] The manufacturing process for sanitary paper base paper preferably further includes a winder part after the reel part. In the winder part, two or more rolls each made of one layer of base paper obtained in the reel part are preferably prepared, and the base paper from each roll is preferably overlapped to form two-ply sanitary paper base paper. After the overlapping step of the base paper, a rewinding step may be provided to form a base roll. In addition, the winder part may subject the two-ply sanitary paper base paper to a calendering treatment.

[0045] The method for producing moisturizing sanitary paper in this embodiment includes a step of applying a moisturizing solution to the sanitary paper base paper that forms the first and second plies. In this embodiment, for example, it is preferable to use different solids concentrations for the moisturizing solution applied to the sanitary paper base paper that forms the first and second plies, or to adjust the coating amount of the moisturizing solution applied to the sanitary paper base paper that forms the first and second plies. Specifically, it is preferable that the solids concentration of the moisturizing solution applied to the sanitary paper base paper that forms the first ply is equal to or higher than the solids concentration of the moisturizing solution applied to the sanitary paper base paper that forms the second ply, and it is even more preferable that the solids concentration of the moisturizing solution applied to the sanitary paper base paper that forms the first ply is higher than the solids concentration of the moisturizing solution applied to the sanitary paper base paper that forms the second ply.

[0046] In the process of applying moisturizing liquid to the sanitary paper base paper that forms the first and second plies, it is preferable to apply the moisturizing liquid to both the first and second plies, but it may also be applied to only one of the plies. In this case, it is preferable to apply the moisturizing liquid from the first ply side. Note that the moisturizing liquid may also be applied to the surface where the plies come into contact when stacked (the inner surface in the case of two-ply sanitary paper). When applying moisturizing liquid to only one ply, the desired P / Q value can be achieved by adjusting the concentration and amount of moisturizing liquid applied and appropriately controlling the permeability of each ply.

[0047] When the moisturizing solution is applied to only one of the plies, it may be applied while the first and second plies are overlapped. Alternatively, when the moisturizing solution is applied to the surfaces where the plies contact each other, it may be applied to one of the plies before the plies are bonded together. In this case, the time from applying the moisturizing solution to bonding the sheets that make up the plies is preferably 10 seconds or less, more preferably 5 seconds or less, and even more preferably 3 seconds or less. This allows the moisturizing solution to be uniformly dispersed from the coated ply (first ply) to the uncoated ply (second ply). Furthermore, applying the moisturizing solution to the surfaces where the plies contact each other when stacked can prevent contamination of the manufacturing equipment by the moisturizing solution. Note that when the moisturizing solution is applied to only one of the plies, it is preferable that the moisturizing sanitary paper is not embossed. Sanitary paper without embossing does not have an unnecessarily high sheet density and has minimal unevenness on the sheet surface, which more effectively increases the penetration of the coated moisturizing solution in the thickness direction.

[0048] The moisturizing liquid is preferably applied to both the first and second plies. In this case, the solids concentration of the moisturizing liquid (A) applied to the sanitary paper base paper that forms the first ply is preferably 20% by mass or more, more preferably 25% by mass or more, and even more preferably 30% by mass or more. The solids concentration of the moisturizing liquid (A) applied to the sanitary paper base paper that forms the first ply is preferably 95% by mass or less, more preferably 90% by mass or less, and even more preferably 85% by mass or less. The moisturizing liquid (A) preferably contains glycerin as a humectant, and the glycerin concentration contained in the moisturizing liquid (A) is preferably within the above range.

[0049] The moisturizing liquid (B) coated on the sanitary paper base paper that forms the second ply preferably has a solids concentration of 15% by mass or more, more preferably 18% by mass or more, and even more preferably 21% by mass or more. The moisturizing liquid (B) coated on the sanitary paper base paper that forms the second ply preferably has a solids concentration of 95% by mass or less, more preferably 90% by mass or less, and even more preferably 85% by mass or less. The moisturizing liquid (B) preferably contains glycerin as a humectant, and the glycerin concentration in the moisturizing liquid (B) is preferably within the above range.

[0050] The moisturizing liquid (A) preferably contains water, and the water content relative to the total mass of the moisturizing liquid (A) is preferably 80% by mass or less, more preferably 75% by mass or less, and even more preferably 70% by mass or less, and the water content relative to the total mass of the moisturizing liquid (A) is preferably 5% by mass or more, more preferably 10% by mass or more, and even more preferably 20% by mass or more.

[0051] The moisturizing liquid (B) preferably contains water, and the water content of the moisturizing liquid (B) is preferably 85% by mass or less, more preferably 80% by mass or less, and even more preferably 75% by mass or less relative to the total mass of the moisturizing liquid (B). The water content of the moisturizing liquid (B) is preferably 5% by mass or more, more preferably 10% by mass or more, and even more preferably 20% by mass or more relative to the total mass of the moisturizing liquid (B).

[0052] In this embodiment, by setting the solids concentration and water content in the moisturizing solution within the above ranges, the permeability of the moisturizing solution can be increased, which makes it easier to produce moisturizing sanitary paper with excellent quality (softness). Furthermore, by setting the water content in the moisturizing solution to the above upper limit or less, paper breakage during the production of moisturizing sanitary paper can be effectively prevented.

[0053] The moisturizing solution preferably contains glycerin as a solid component. The moisturizing solution may contain other components in addition to glycerin and water. The other components may be humectants other than glycerin. Examples of such humectants include diglycerin, propylene glycol, 1,3-butylene glycol, polyethylene glycol, sorbitol, glucose, xylitol, maltose, maltitol, mannitol, trehalose, polyglycerin, lactic acid, and sodium lactate. A preferred embodiment of the moisturizing solution contains only glycerin as the humectant. Other components besides the humectant include softeners, emulsifiers, antifoaming agents, preservatives, and lubricating oils. The content of other components in the moisturizing solution is preferably 10% by mass or less, more preferably 8% by mass or less, and even more preferably 6% by mass or less, based on the total mass of the moisturizing solution. Commercially available moisturizing solutions may generally contain several percent by mass of the above-mentioned other components and solvents other than water.

[0054] The step of applying a moisturizing solution to the sanitary paper base paper is preferably a step of gravure coating the moisturizing solution onto the sanitary paper base paper. The application speed of the moisturizing solution in the gravure coating step is preferably 50 m / min or more, more preferably 75 m / min or more, even more preferably 100 m / min or more, even more preferably 125 m / min or more, and particularly preferably 150 m / min or more. The upper limit of the application speed of the moisturizing solution is not particularly limited, but is preferably, for example, 500 m / min or less. By setting the application speed of the moisturizing solution within the above range, the productivity of moisturizing sanitary paper can be more effectively improved.

[0055] The step of applying a moisturizing solution to the sanitary paper base paper may also be a step of spraying the moisturizing solution onto the sanitary paper base paper. The spray application step preferably uses a spray sprayer, and examples of such spray sprayers include a two-fluid spray sprayer that mixes moisturizing solution with compressed air and sprays it. For example, a two-fluid intermittent spray spraying nozzle manufactured by Spraying Co., Ltd. may be used in the spray application step. The step of applying the moisturizing solution to the sanitary paper base paper may also use a liquid applicator. An example of a liquid applicator is a rotor dump.

[0056] The step of applying the moisturizing liquid may include a step of recovering excess moisturizing liquid, which can then be reused.

[0057] In this embodiment, a step of diluting the moisturizer concentrate may be provided before the step of applying the moisturizer. The step of diluting the moisturizer concentrate is preferably a step of diluting the moisturizer concentrate with water. By providing a step of diluting the moisturizer concentrate, it is possible to reduce the transportation and storage costs of the moisturizer concentrate, and as a result, the production costs of moisturized sanitary paper. Furthermore, in this embodiment, moisturizer concentrate containing a high concentration of solids such as glycerin is diluted and then coated onto sanitary paper base paper, thereby producing moisturized sanitary paper with excellent quality (softness).

[0058] After the step of applying the moisturizing liquid to the sanitary paper base paper, a re-winding step may be performed to form a sanitary paper roll. Note that the steps of applying the moisturizing liquid and re-winding can also be performed simultaneously.

[0059] The density of the roll obtained after applying the moisturizing solution (roll after application) is 0.10 g / cm 3 It is preferable that the concentration is 0.13 g / cm or more. 3 More preferably, it is 0.15 g / cm or more. 3 Furthermore, the density of the roll obtained after the application of the moisture-retaining solution is 0.35 g / cm or more. 3Preferably, it is 0.30 g / cm or less. 3 More preferably, it is 0.25 g / cm or less. 3 More preferably, it is 0.20 g / cm or less. 3 By setting the roll density after coating within the above range, the feel of the sanitary paper surface can be improved. 3 By setting the density to 0.35 g / cm or more, the penetration of the chemical is improved, and the chemical is more likely to penetrate uniformly. 3 By doing so, it is possible to more effectively increase the permeability of the moisturizing solution and obtain moisturizing sanitary paper that has an excellent feel to the touch, which makes it easier to obtain moisturizing sanitary paper that maintains softness while having sufficient strength. Here, the roll obtained after the moisturizing solution application (post-coating roll) refers to the roll that has been subjected to the moisturizing solution application process and then wound up in the next process. The post-coating roll may be a roll in the finished product state, or it may be a secondary web obtained after the moisturizing solution application. The secondary web is then unwound and reprocessed into a product. That is, the density of the roll obtained after the moisturizing solution application may be the winding density of the roll product, or it may be the winding density of the secondary web obtained in the manufacturing process for the roll product. Note that in the method for obtaining the secondary web, the product is processed after the moisturizing solution has permeated, so the winding density of the product may be low. In the method for obtaining the secondary web, the aging time required for the moisturizing solution to permeate is preferably 12 hours or more, and more preferably 24 hours or more.

[0060] The density of the wound film obtained after the application of the moisture-retaining solution is calculated by the following formula: The roll radius and core radius are calculated from their respective outer circumferences. The density of the roll obtained after applying the moisturizing liquid (g / cm 3 ) = Roll weight / (roll radius x roll radius x 3.14 x width - core radius x core radius x 3.14 x width) Whether it is secondary raw roll or rolled product, the roll weight is measured after conditioning for 24 hours in an environment conforming to ISO187 (temperature 23±1°C, relative humidity 50±2%). For secondary raw rolls where direct weight measurement is difficult, the roll weight can be calculated as follows: conditioned basis weight x number of plies x width x length. Furthermore, if aging is performed after obtaining the secondary raw roll, the roll weight is measured after aging. In the case of tissue products, which are not rolled but are bundles of folded and stacked sheets, the roll density can be calculated using the following method. Flux density after applying moisturizing liquid (g / cm 3 ) = Bundle weight / (Bundle width x Bundle length x Bundle height)

[0061] In the rewinding process, embossing may be performed when the layers are bonded together. Embossing is performed by applying pressure to the sheet with an embossing roll that has been given an embossing pattern. By changing the pressing amount or pressing pressure of the embossing roll, an embossed shape with a predetermined embossing height can be formed in the sanitary paper containing moisturizing liquid. When embossing, the embossing may be performed in a state where multiple layers are stacked so that the front and back of the sanitary paper can be distinguished, or the stacked sanitary paper may be separated and each layer may be subjected to a different embossing treatment before being stacked.

[0062] In this embodiment, it is preferable that the sanitary paper is not embossed, and does not have an embossed surface. With sanitary paper that is not embossed, the sheet density is not higher than necessary, and the sheet surface has fewer irregularities, which more effectively increases the penetration of the applied moisturizing solution in the thickness direction.

[0063] In the rewinding process, the sanitary paper containing moisturizer may be laminated by providing a narrow contact embossment (a bonding embossment) at the edge of the product after the sanitary paper containing moisturizer is stacked, or by applying an adhesive or the like to the edge. When providing a narrow contact embossment at the edge of the product after the sanitary paper containing moisturizer is stacked, the contact embossment may be formed, for example, on both side edges in the width direction (CD) of the sanitary paper so as to extend along its length direction (MD). When formed in this manner, it is also called an edge embossment. The contact embossment may be formed so as not to protrude outward in the thickness direction from either the front or back of the sanitary paper.

[0064] The step of applying the moisturizing liquid and the step of embossing can be performed separately. After applying the moisturizing liquid, the substrate may be temporarily wound up and aged to allow the moisturizing liquid to penetrate, and then embossed.

[0065] In the winding process, the paper may be wound while forming tearing perforations at regular intervals along the length of the paper. In the end-of-winding processing section, the end of the long sanitary paper discharged from the winding section is preferably glued along the width to prevent the long sanitary paper from unraveling. The resulting roll is then cut to a specified width to produce a sanitary paper roll product. [Example]

[0066] The features of the present invention will be explained in more detail below with reference to examples and comparative examples. The materials, amounts used, ratios, treatment contents, treatment procedures, etc. shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention should not be construed as being limited by the specific examples shown below.

[0067] (Example 1) Pulp slurry was prepared by mixing 20% ​​by mass of softwood kraft pulp (NBKP) and 80% by mass of hardwood kraft pulp (LBKP). The mixture was refined using a double-disc refiner to a freeness of 700 ml. The resulting pulp slurry was then made into paper using a twin-wire Yankee machine at a J / W ratio of 0.97, yielding a paper with a basis weight of 16.4 g / m. 2 The toilet paper base paper roll was obtained. The basis weight is the measured value per ply measured in accordance with JIS P 8124. Two of the obtained rolls of base paper were put into a processing machine and laminated into two plies to obtain a two-ply toilet paper roll.

[0068] A moisturizing solution A containing 30% by mass of glycerin and 70% by mass of water was prepared as a coating solution. Next, moisturizing solution A was diluted with water to prepare moisturizing solution B containing 29% by mass of glycerin and 71% by mass of water. A two-ply toilet paper was unwound from the original roll, the ply sheets were separated, and the upper sheet (the ply sheet on the front side when wound on the original roll (first ply sheet)) and the lower sheet (the ply sheet on the back side when wound on the original roll (second ply sheet)) were each passed through an offset gravure coating device. In the coating section of the coating device, moisturizing liquid A and moisturizing liquid B were applied to the upper sheet (first ply sheet) and the lower sheet (second ply sheet), respectively, at a coating speed of 200 m / min so that the application amounts shown in Table 1 were obtained. The moisturizing agent content was calculated from the wet application amount, and the combined amount of the upper sheet and the lower sheet was the moisturizing agent content of the two-ply toilet roll product. Two seconds after applying the moisturizing solution, the upper and lower sheets were stacked again (with the moisturizing solution-coated surfaces facing inward), and wound up to a length of 40 m. The resulting roll was then cut to a width of 114 mm to obtain a two-ply toilet paper roll product. The winding density of the toilet paper roll product was 0.19 g / cm. 3 It was.

[0069] (Examples 2-4) A two-ply toilet paper roll product was obtained in the same manner as in Example 1, except that the moisturizing solution B shown in Table 1 was obtained by changing the dilution ratio of moisturizing solution A and the amount of moisturizing solution applied was shown in Table 1.

[0070] (Examples 5-27) A two-ply toilet paper roll product was obtained in the same manner as in Example 1, except that moisturizing solution A and moisturizing solution B shown in Table 1 were used and the amount of moisturizing solution applied was shown in Table 1.

[0071] (Example B1~B6) A two-ply toilet paper roll product was obtained in the same manner as in Example 1, except that moisturizing solutions A and B with the same compositions as shown in Table 1 were used and the amount of moisturizing solution applied was as shown in Table 1.

[0072] (evaluation) <Toilet paper softness> A 1m section was unwound from the outside of the products (rolls) obtained in the Examples and Comparative Examples, and the softness of the toilet paper was evaluated by touch. Specifically, 50 people touched the toilet paper obtained in the Examples and Comparative Examples, and the softness of the toilet paper was compared with that of each of the control products B1 to B6 (P / Q = 1.00) and rated on a three-point scale: 3: feels very soft, 2: feels soft, 1: does not feel soft. The softness of toilet paper was evaluated based on the same moisturizer content (g / m 2 ) was used as a standard for evaluation. That is, in Examples 1 to 4, the softness was evaluated using Control Product B1 as a standard, in Examples 5 to 8, the softness was evaluated using Control Product B2 as a standard, and in Examples 9 to 15, the softness was evaluated using Control Product B3 as a standard. In Examples 16 to 19, softness was evaluated based on control product B4, in Examples 20 to 23, softness was evaluated based on control product B5, and in Examples 24 to 27, softness was evaluated based on control product B6. Then, the average value ratio to the control products B1 to B (P / Q=1.00) was calculated using the following formula. Average value ratio = average value of three-level evaluation of the example / average value of three-level evaluation of blank (with the same coating amount as the example) In the table below, the evaluation criteria for relative evaluation are as follows: 〇: More than 1.10 △: More than 1.05 but less than 1.10 ×: 1.05 or less

[0073] [Table 1]

[0074] Moisturizing agent content: 3.2g / m 2 When the content of the moisturizing agent exceeds 3.2 g / m, the film becomes prone to tearing, and production efficiency tends to decrease. 2 When the P / Q value was exceeded, the skin felt soft and sticky, regardless of the P / Q value. 2 Below this, all samples were inferior in softness. [Explanation of symbols]

[0075] 20. Toilet paper 20a outer toilet paper 20b inner toilet paper 100 toilet rolls

Claims

1. A two-ply moisturizing sanitary paper sheet having a first ply and a second ply laminated thereon, The moisturizing sanitary paper contains a moisturizing agent, and the content of the moisturizing agent is 0.3 g / m ２ 3.2g / m or more ２ is less than When the content of the moisturizing agent in the first ply is P and the content of the moisturizing agent in the second ply is Q, P>Q and the value of P / Q is 1.10≦P / Q≦1.

35.

2. A toilet roll comprising the moisturizing sanitary paper according to claim 1 wound into a roll.

3. 3. The toilet roll of claim 2, wherein the first ply is disposed on the outer wound side of the roll.

4. A moisturizing sanitary paper container in which a plurality of sets of the moisturizing sanitary paper according to claim 1 are stacked, folded so as to pop up, and contained in a package.

5. The moisture-retaining sanitary paper container according to claim 4 , wherein the first ply is disposed on the outside when the moisture-retaining sanitary paper is folded in a mountain fold.

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