CN113330158A

CN113330158A - Toilet paper

Info

Publication number: CN113330158A
Application number: CN202080010190.9A
Authority: CN
Inventors: 保井秀太; 岩崎穣
Original assignee: Daio Paper Corp
Current assignee: Daio Paper Corp
Priority date: 2019-03-06
Filing date: 2020-02-12
Publication date: 2021-08-31
Anticipated expiration: 2040-02-12
Also published as: KR102683635B1; JP2020141870A; JP7175801B2; WO2020179379A1; EP3907328B1; KR20210134645A; CN113330158B; EP3907328A1; US20220127790A1; EP3907328A4

Abstract

[ problem ] to]The invention provides a toilet paper which has excellent thickness feeling and hydrolyzability, sufficient flexibility, feeling of reassurance to human body when in use, and environmental protection. [ solution means ] to]The toilet paper is 3-4 layers of toilet paper, and the basis weight of 1 layer is 10.5-12.5 g/m²50 to 100 mass% of the fibers are softwood kraft pulp which is oxygen-digested and not chlorine-bleached, and which contains a cationic fatty acid amide softener, wherein the thickness of 1 layer is 80 to 100 μm, the thickness of the entire toilet paper is 320 to 400 μm, and the hydrolyzability is 10 seconds or less.

Description

Toilet paper

Technical Field

The invention relates to toilet paper.

Background

Toilet paper is sometimes required to have wiping properties when a shower toilet bowl, also called a toilet bowl with a cleaning function, is used (patent document 1).

In the case of toilet paper suitable for a toilet bowl, a multi-layer product of 3 or 4 layers is considered desirable because consumers can easily feel a sense of reassurance when using it.

Incidentally, although toilet paper is generally bleached with a chlorine-based bleaching agent such as chlorine, chlorine dioxide, or sodium hypochlorite as a fiber material in order to improve whiteness, consumers who pay attention to the feeling of reassurance on the human body and the consideration of the environment also desire a product in which the environment and the like are considered using pulp without using a chlorine-based bleaching agent as a material.

In addition, toilet paper is generally produced from a fiber raw material in which hardwood-derived pulp having a short fiber length and softwood-derived pulp having a long fiber length are mixed, and generally, hardwood-derived pulp which is easily improved in softness and surface properties is mainly contained in a large amount.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2011-153387

Disclosure of Invention

Problems to be solved by the invention

However, the pulp not bleached with the chlorine bleaching agent has a large amount of lignin remaining therein and has hard fibers, and toilet paper using the pulp as a main fiber material is likely to have hardness or surface roughness.

On the other hand, it is known that the strength of paper is reduced by further increasing the amount of hardwood pulp mixed in order to make the paper more flexible, but the hydrolysis is easily deteriorated by increasing the amount of hardwood pulp mixed in. In particular, since the multi-layer product is liable to be deteriorated in hydrolyzability, if the amount of hardwood pulp is increased, the multi-layer product may not be suitable for use in a shower toilet.

In addition, hardwood pulp tends to produce paper dust due to the short fiber length. Further, when a softening agent is used, paper dust is more likely to be generated.

Accordingly, a main object of the present invention is to provide a toilet paper which has a thickness feeling that can be relieved in a situation where the toilet paper is used in a shower toilet, is sufficiently flexible, is less likely to generate paper powder, has excellent hydrolyzability, and has a feeling of relief for a human body when used.

Means for solving the problems

The first means for solving the above problems is a toilet paper having 3 to 4 layers, characterized in that,

50 to 100 mass% of the fibers are conifer sulfate pulp that has been oxygen digested and not chlorine bleached,

the toilet paper contains a cationic fatty acid amide softener,

the basis weight of the 1 layer is 10.5-12.5 g/m²，

The thickness of the paper of 1 layer is 80-100 μm, the thickness of the paper based on the whole toilet paper is 320-400 μm,

the hydrolyzability is 10 seconds or less.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, there is provided a toilet paper which has a thickness feeling that can be relieved in a situation where the toilet paper is used in a shower toilet, is sufficiently flexible, is less likely to generate paper powder, has excellent hydrolyzability, and has a feeling of relief for a human body when used.

Drawings

Fig. 1 is a plan view of an emboss of an embodiment of the present invention.

Fig. 2 is a schematic view for explaining the measurement process of the embossing depth of the present invention.

Fig. 3 is a perspective view of a roll of toilet paper according to an embodiment of the present invention.

Detailed Description

The toilet paper of the present embodiment has 3 or 4 layers. Namely, 3 or 4 sheets were overlapped. By forming a plurality of layers of more than 2, such as 3 or 4 layers, the thickness of the entire paper can be increased while making each layer thin, and in particular, a toilet paper which is easy to feel "soft" and has a feeling of reassurance that it is not easily broken can be formed.

In addition, if the number of layers is 2, it is difficult to give a sense of thickness, and a sense of reassurance tends to be low when wiping while absorbing a large amount of water after use of the toilet bowl. In addition, if the number of layers is 5 or more, even if the layers are made thin, softness is not easily felt when the skin is cleaned. When the laminate is formed into 5 or more layers under the conditions of basis weight and paper thickness per 1 layer of the present invention to be described later, particularly when embossing is applied, a strong rigid feeling is felt, and flexibility is hardly felt.

On the other hand, in the toilet paper of the present embodiment, the basis weight per 1 layer is 10.5g/m²Above 12.5g/m²The following. Preferably 10.6g/m²Above and below 12.4g/m²More preferably 10.7g/m²Above 12.3g/m²The following. When the basis weight of 1 layer is within this range, the above-mentioned 3 or 4 layers can have sufficient indestructibility and good texture. In addition, hydrolyzability is easily exhibited. The basis weight of the present invention was obtained by the basis weight measurement method of JIS P8124 (1998).

On the other hand, in the toilet paper of the present invention, the main fibers constituting the fibers, i.e., 50% by mass or more, need to be conifer sulfate pulp that has been oxygen-digested without chlorine bleaching. Preferably 80% by mass or more, particularly preferably substantially 100% by mass without taking impurities and the like into account, is softwood kraft pulp that has been oxygen digested and not chlorine bleached. More specifically, the kraft pulp of conifers, also called NOKP, is produced by continuous oxygen cooking in a continuous cooking vessel, and in particular, is not subjected to a bleaching treatment with a chlorine-based bleaching agent thereafter. Here, KP (kraft pulp) used in toilet paper includes bleached KP and unbleached KP, and the unbleached KP contains a large amount of lignin. The kraft softwood pulp of the present invention is not bleached with a chlorine-based bleaching agent, but is subjected to oxygen cooking (oxygen delignification), so that about half of the lignin is removed. The meaning of the chlorine-based bleaching agent includes not only chlorine but also chlorine dioxide and sodium hypochlorite. Thus, ECF (elemental chlorine free bleached) pulp is not the above-described softwood kraft pulp of the present invention.

The toilet paper of the present invention contains 50% by mass or more, preferably 80 to 100% by mass or more, of conifer kraft pulp which has not been bleached with a chlorine-based bleaching agent but has been delignified by oxygen cooking. That is, since the kraft pulp of coniferous trees is produced as a main fiber material, particularly as a whole fiber material, it has a feeling of reassurance to the human body when used, and is environmentally friendly. In particular, toilet paper containing 50 mass% or more of the kraft pulp of conifers is light brown, is visually likely to have an impression similar to natural materials which have not been chemically treated, and has a soft impression, and therefore, a purchaser feels a great sense of reassurance.

On the other hand, the delignification treatment by oxygen cooking reduces lignin to about half of that before oxygen cooking, and therefore, compared with a pulp which is not delignified at all as a raw material, the pulp tends to exhibit flexibility and to have sufficient strength. Further, the hardwood kraft pulp, which can easily reduce the hydrolyzability, is at least less than 50 mass%, particularly 0 mass%, and the hydrolyzability is easily improved, so that paper dust is hardly generated.

In addition, since lignin is not hydrophilic, softwood kraft pulp containing lignin that has been oxygen digested and not chlorine bleached has low fiber swelling and weak interfiber bonds. Therefore, the fibers become loose and the hydrolyzability becomes good. In addition, since softwood kraft pulp is derived from softwood, the fiber length is longer than that of hardwood pulp, so that paper dust is less likely to be generated, and the effect of lignin on preventing fiber densification is combined to provide pulp having excellent cushioning properties.

The fiber components other than the softwood kraft pulp that has been oxygen-digested and not bleached with chlorine are not limited, but hardwood kraft pulp that has been oxygen-digested and not bleached with chlorine is preferable in that it has a light brown appearance and a feeling of reassurance that bleaching with a chlorine-based bleaching agent is not achieved. Other virgin pulp and waste paper pulp can be used. In the process of regenerating pulp from waste paper, the pulp tends to be finer in fiber than pulp fiber before regeneration, and due to the properties of the fiber, the fiber tends to be dense without increasing the thickness of the paper, and the paper strength tends to be improved. On the other hand, if the blending amount is too large, the hand such as flexibility is lowered. Therefore, in view of the characteristics of the used paper pulp, the compounding ratio thereof is preferably determined in the range of 0 or more and less than 20 mass%. The kind of the used paper pulp is not necessarily limited. Waste paper pulp made from milk carton waste paper and high-quality waste paper can be used.

The toilet paper of the present invention comprises 50 to 100 mass% of softwood kraft pulp that has been oxygen digested and not chlorine bleached, and has a basis weight of 1 ply as low as 10.5 to 12.5g/m²And further, a multi-layer structure of 3 or 4 layers can provide an environmentally friendly toilet paper which is excellent in thickness feeling and hydrolyzability, is sufficiently flexible, hardly generates paper powder, and has a feeling of reassurance to the human body when used.

On the other hand, the toilet paper of the present invention is preferably a non-humectant-coated toilet paper which is not substantially coated with a humectant. The humectant as the external additive of the present invention is polyhydric alcohols, and at least includes glycerin, diglycerin, propylene glycol, 1, 3-butylene glycol, and polyethylene glycol. However, if the degree of influence of the above components is only not so high as to be called moisturizing toilet paper, the inclusion of the above components is not denied. The toilet paper of the present invention is excellent in feeling of reassurance to the human body, and when the moisturizing agent is applied, the toilet paper feels sticky and moist feeling peculiar to the moisturizing agent, so that the feeling of reassurance to the human body is reduced.

On the other hand, the toilet paper of the present invention contains a softener that determines the flexibility and paper strength of the base paper itself and is added during the papermaking. The softening agent contained in the toilet paper of the present invention is a cationic fatty acid amide-based softening agent. The cationic fatty acid amide-based softening agent has an effect of coating the surface of the fiber without reducing the effect of containing lignin. Even if a pulp containing lignin is blended in a high proportion, the surface is smooth, the hardness is remarkably reduced, and the fluffy feeling is also improved. Specific examples of the cationic fatty acid amide-based softening agent are preferably a reaction product of an amide-based compound obtained by the reaction of a polyalkylene polyamine and a monocarboxylic acid and epihalohydrin. The cationic fatty acid amide-based softening agent exhibits an effect. When a reaction product of an amide compound obtained by a reaction between a polyalkylene polyamine and a monocarboxylic acid and epihalohydrin is added, it is preferable to add the amide compound mixed with an emulsifier having an alkyl group and/or an alkenyl group having 4 to 20 carbon atoms and water. The content of the cationic fatty acid amide-based softener is not particularly limited, and the amount of the softener added during production may be 0.5 to 4.0 kg/ton of pulp at an attachment ratio of 50 to 60%.

In addition, the toilet paper of the invention is preferably internally added with a soft humectant. The content is preferably 0.2 to 2.0 kg/ton pulp. By including a softening humectant, softness is improved. Particularly preferred softening moisturizers are the reaction products obtained as follows: the alkylene oxide having 2-4 carbon atoms is added to the active hydrogen of the polyalkyleneimine having a weight average molecular weight of 500-10,000, and the obtained compound is reacted with a higher fatty acid having 12-24 carbon atoms and/or an ester compound of a higher fatty acid having 12-24 carbon atoms. By including the softening moisturizer, the softness is further improved.

In the toilet paper, the thickness of 1 layer of the toilet paper is 80-100 mu m, and the thickness of the toilet paper is 320-400 mu m in terms of the whole toilet paper. When the paper thickness is within this range, the bulkiness and flexibility are excellent, and a comfortable thickness feeling is obtained. The method for measuring the paper thickness of toilet paper is carried out by humidifying a test piece sufficiently (usually about 8 hours) under the conditions of JIS P8111 (1998) and then measuring the conditioned test piece in a state of 1 ply under the same conditions using a dial gauge (thickness measuring instrument) "PEACOCK G type" (manufactured by kazaki corporation). Specifically, it was confirmed that there was no dirt, dust, or the like between the plunger and the measuring table, the plunger was lowered onto the measuring table, the scale of the dial thickness gauge was moved to zero, the plunger was then lifted up, the sample was placed on the test bed, and the plunger was slowly lowered to read the number of meters (gauge) at that time. When the toilet paper is embossed, one of the formed concave portions (convex portions) must be brought into the range of the measurement table. When there are recesses having different depths, the recess having the deepest depth is located in this range. At the time of this measurement, the plunger was simply set without pressing. The terminal of the plunger was made of metal, and a circular flat surface having a diameter of 10mm was brought into contact with a paper plane perpendicularly, and the load during the measurement of the paper thickness was about 70 gf. The paper thickness was an average value obtained by 10 measurements. Here, although it is conceivable that the embossments (recesses) are crushed when the paper thickness is measured, the paper thickness of the present invention is a value measured including such crush, and such crush is negligible. In the paper thickness measurement, the difference in paper thickness due to collapse of the concave portion is negligible.

The toilet paper of the present invention preferably comprises pulp fibers that are not unbleached. The freeness of the papermaking raw material in the production is not necessarily limited, but it is preferable to carry out beating so that the reduction of the canadian standard freeness is 20cc to 50 cc. This decrease is very small compared with the beating range of a general papermaking raw material. In this case, the canadian standard freeness of the papermaking raw material is approximately 600cc or more. By not beating too much pulp fibers and not beating them, when the softening agent is included in the pulp, the softening agent is easily fixed to the fiber surface, and the fibers are appropriately entangled with each other, so that a desired low paper thickness is easily achieved, and the pulp becomes excellent in softness and also has a good bulky feeling. Moreover, paper dust is extremely difficult to produce. Further adjustment of the caliper can be further performed by the creping rate.

The toilet paper of the invention can be embossed. The embossing pattern thereof is not necessarily limited. The embossing may be a suitable embossing pattern such as micro-embossing, dot embossing, design embossing, or the like. Among them, the embossing pattern of the present invention is preferably an embossing given in a layer-by-layer state called single-sided embossing.

In the preferred embossing pattern of the present invention, the area of the concave part is 1.0 to 2.5mm²The density is 5.0 to 50 pieces/cm²The embossing depth is 0.05-0.5 mm. The toilet paper has improved softness, and the toilet paper has improved softness in a rolled state like rolled toilet paper, and is easy for consumers to feel when holding in their handsIs subjected to softening. In particular, as shown in fig. 1, square recesses 31 (fig. 1A) having a bottom face with a diagonal L4 × a diagonal L4 of 1.0 to 1.5 × 1.0 to 1.5mm or recesses 32 of an approximate square (fig. 1B) extending outside the four diagonal corners of the square are arranged in a grid pattern at an arrangement angle of 45 ° with respect to the width direction at a center interval L5 of 4.5 to 5.5mm over the entire paper surface, and valley portions 33 extending from the four corners of the recesses are provided between the recesses 31(32) and the recesses 31 (32). The valley portion 33 is preferably arranged as follows: the cross section is gradually and gently formed in an arcuate shape so that the four corners of the concave portions 31(32) are deepest and the middle between the concave portions is shallowest. The embossed pattern is excellent in flexibility and wiping properties of feces.

The depth of the embossings was measured using an ONESHOT 3D measuring microscope VR-3200 manufactured by KEYENCE CORPORATION, Inc. or an equivalent instrument thereof, and image analysis software "VR-H1A" or an equivalent software thereof. The measurement was performed under conditions of magnification of 12 times and a field area of 24 mm. times.18 mm. The magnification and the viewing area may be appropriately changed according to the size of the embossings (recesses). A specific measurement procedure will be described with reference to fig. 2, and the above-described software is used to obtain the distribution of the embossing depth (measurement cross-sectional curve) at a line segment Q1 that crosses the longest portion of the peripheral edge of one of the embosses (concave portions) 40 in the image portion (X portion in the figure) displayed in a plan view. The wavelength ratio λ c: the "profile curve Q2" of an image portion (Y portion in the figure) displayed in a cross-sectional view was obtained by obtaining a short surface roughness component of 800 μm (where λ c is "a filter defining a boundary between a roughness component and a moire component" described in JIS-B0601 "3.1.1.2"), and the minimum values of 2 recess edge points P1 and P2 which are convex upward and most strongly curved in the obtained "profile curve Q2" and the minimum values of the values sandwiched between the recess edge points P1 and P2 were obtained as the minimum value Min of the depth. Further, the average of the depth values of the recess edge points P1, P2 is set as the maximum value Max of the depth. Thus, the embossing depth is the maximum Max-minimum Min. Further, the distance (length) between the recess edge points P1 and P2 on the X-Y plane is defined as the length of the longest portion. The above-mentioned 2 recess edge points P1, P2, which are convex upward and most strongly bent, are selected by visual observation. In the selection, the outline E in the image in the plan view of the emboss (recess) 40 in the measurement may be used as a reference. Similarly, the depth of the emboss (recess) is also measured for the shortest portion in the direction perpendicular to the longest portion, and a large value is adopted as the depth of the emboss (recess). The above measurements were made for any 10 embossings on the surface of the toilet paper, and the average value was taken as the final embossing depth.

The area of each concave portion of the embossed pattern was also measured by using an ONESHOT 3D measurement microscope VR-3200 or an equivalent instrument and image analysis software "VR-H1A" or an equivalent software, and the contour of the embossed concave portion was visually confirmed from the obtained 3D image to measure the area inside the contour. Any 10 embossings on the surface of the toilet paper were measured, and the average value thereof was defined as the area of the final embossed depressions.

In addition, the toilet paper of the invention has hydrolysis performance within 10 seconds and is very quick. This is because 50% by mass or more, preferably 80% by mass or more, and particularly 100% by mass of the constituent fibers are softwood kraft pulp containing lignin, and the fibers tend to be loose. If the hydrolyzability is within 10 seconds, the possibility of clogging the piping when the running water is discarded in a toilet or the like is significantly reduced. The hydrolyzability (ease of looseness) was measured in accordance with JIS P4501 (1993). In the ease of looseness test, a 300mL beaker containing 300mL of water (water temperature 20. + -. 5 ℃) was placed on a magnetic stirrer, and the rotation speed of the rotor was adjusted to 600. + -. 10 rpm. A test piece having a side length of 100. + -.2 mm square was put into the flask, and a stopwatch was pressed. The rotation speed of the rotor temporarily dropped to about 500 revolutions due to the resistance of the test piece, and the rotation speed increased as the test piece was loosened. The stopwatch was stopped at the time when the rotational speed was returned to 540 revolutions, and the time was measured in units of 1 second. The results of 5 tests were obtained, and the mean value of the results was used as the degree of looseness. The rotor is a disc-shaped rotor with the diameter of 35mm and the thickness of 12 mm.

The dry tensile strength of the toilet paper of the present invention in the machine direction is preferably 500cN/25mm to 1200cN/25mm, more preferably 600cN/25mm to 1000cN/25 mm. The dry tensile strength in the transverse direction is preferably 200cN/25mm to 450cN/25mm, more preferably 200cN/25mm to 350cN/25 mm. Within this range, the durability is sufficient.

The longitudinal direction of the paper is also referred to as MD direction, and is the flow direction in papermaking. The cross direction of the paper is also called the CD direction, and is a direction perpendicular to the flow direction (MD direction) during paper making. The dry tensile strength of the present invention is a value measured in accordance with JIS P8113 (2006), and is measured as follows. Test pieces cut to a width of 25mm (+ -0.5 mm) X a length of about 150mm were used in both the longitudinal and transverse directions. The test piece was directly measured in a multilayer state. The tensile testing machine used was a load cell tensile testing machine TG-200N manufactured by Minebea corporation and an equivalent device. The interval between chucks was set at 100mm, and the drawing speed was set at 100 mm/min. The measurement was carried out according to the following procedure: both ends of the test piece were fastened to chucks of a testing machine, a tensile load was applied to the paper piece in the vertical direction, and an instruction value at the time of paper breakage (in the case of numerical value representation, this numerical value) was read. 5 groups of samples were prepared in the longitudinal and transverse directions, and the average of the measured values was defined as the dry tensile strength in each direction, 5 times each.

The toilet paper of the present invention preferably has a wet tensile strength in the machine direction of 50cN/25mm or more and 100cN/25mm or less. The wet tensile strength in the transverse direction is preferably 15cN/25mm or more and 70cN/25mm or less. The wet tensile strength is a value measured in accordance with JIS P8135 (1998) and is measured as follows. Test pieces cut to a width of 25mm (+ -0.5 mm) X a length of about 150mm were used in both the longitudinal and transverse directions. When the sheet is a multi-layer sheet, measurement is performed in a multi-layer state as it is. The tensile testing machine used was a load cell tensile testing machine TG-200N manufactured by Minebea corporation and an equivalent device. The interval between chucks was set to 100mm, and the drawing speed was set to 50 mm/min. The test piece was cured (cured) for 10 minutes by a drier at 105 ℃. The measurement was carried out according to the following procedure: after both ends of the test piece were fastened to chucks of a testing machine, water was horizontally applied to the center portion of the test piece with a flat brush containing water at a width of about 10mm, and immediately thereafter, a tensile load was applied to the paper piece in the vertical direction, and an indicated value (numerical value) at the time of paper breakage was read. 5 groups of samples were prepared in the longitudinal and transverse directions, and the average of the measured values was defined as the wet tensile strength in each direction, 5 times each. The wet tensile strength was also measured by stacking a plurality of sheets depending on the number of layers of the product.

In the toilet paper of the present invention, the MMD, which is an index indicating surface properties, preferably has a value of 7.5 to 11.0. If the MMD is less than 7.5, the surface is excessively slippery, and the wiping property is reduced; if the amount exceeds 11.0, the feel to the skin is poor, and the use as toilet paper may be inappropriate. In the MMD measurement, the contact surface of the friction material was brought into contact with the surface of the measurement sample to which a tension of 20g/cm was applied in a predetermined direction at a contact pressure of 25g, and the surface was moved by 2cm at a speed of 0.1cm/s in the direction substantially the same as the direction in which the tension was applied, and the friction coefficient at that time was measured using a friction-sensitive measuring instrument KES-SE (manufactured by KATO TECH corporation) or an equivalent thereof. The value obtained by dividing the friction coefficient by the friction distance (movement distance ═ 2cm) was MMD. The friction member is formed by 20 piano wires P of 0.5mm in diameter being adjacent to each other, and has a contact surface with a length and a width of 10 mm. On the contact surface, a cell bulging portion formed by 20 piano wires P (curvature radius 0.25mm) was formed at the front end.

The toilet paper of the present embodiment preferably has a softness of 2.0cN/100mm or more and 3.5cN/100mm or less. Softness is one of the indicators of softness, and lower values thereof are considered to be softer. A tissue or toilet paper is considered to be soft when the softness is 3.5cN/100mm or less. The measured value of softness is a value measured by the Handle-O-Meter method in accordance with JIS L1096E method (1990). The test piece was 100mm × 100mm, and the gap was 5 mm. The measurement was performed 5 times in the longitudinal direction and the transverse direction of the single layer, and the average value of all 10 times was obtained. The softness is expressed in terms of cN/100mm in some cases, although it is not a unit, in consideration of the size of the test piece.

In the toilet paper of the present embodiment, the adjustment of the dry tensile strength and the wet tensile strength can be performed without using a paper strength enhancer such as a dry strength agent or a wet strength agent. In addition, it is preferable not to contain a paper strengthening agent particularly from the viewpoint of a sense of distraction of the user. In the toilet paper of the present invention, even if the paper strength agent is not contained, by blending the kraft pulp of conifer having a long fiber length in a high proportion so as to contain 80 mass% or more, particularly 100 mass%, entanglement between fibers can be secured and sufficient strength for use can be obtained. Further, the inclusion of lignin also provides excellent hydrolyzability. That is, sufficient strength can be ensured without using a paper strength-enhancing agent, and further, hydrolysis properties can be improved.

In the toilet paper of the present embodiment, as described above, it is preferable not to use a dry strength agent or a wet strength agent, but it may be used as needed within a range not inhibiting the hydrolyzability. Examples of the dry strength agent include starch, polyacrylamide, CMC (carboxymethyl cellulose) or a salt thereof, sodium carboxymethyl cellulose, calcium carboxymethyl cellulose, and zinc carboxymethyl cellulose.

Examples of the wet strength agent include polyamide polyamine epichlorohydrin resin, urea resin, acid colloid-melamine resin, thermally crosslinkable coated PAM, TS-20 manufactured by seiko PMC corporation, polymer aldehyde-functional compounds such as glyoxalated polyacrylamide and cationic glyoxalated polyacrylamide, copolymers of acrylamide monomers modified with dialdehyde or other dialdehyde and other copolymerizable unsaturated monomers, and dialdehyde starch.

On the other hand, the toilet paper of the present embodiment may be in a form of a single sheet, and as shown in fig. 3, a form of roll toilet paper in which a strip toilet paper 10 is wound in a roll form on a paper core (also referred to as a core) 20 is suitable.

The preferred roll diameter L2 (diameter) of the roll toilet paper is 110-115 mm. The roll diameter of the roll toilet paper is defined to be 120mm or less in JIS P4501, and a holder for mounting a general roll toilet paper is manufactured based on the 120 mm. The roll diameter of the roll toilet paper is 110-115 mm, and the roll toilet paper is enough to be installed on a common bracket. The coil diameter is a value measured using a caliper manufactured by MURATEC-KDS corporation or an equivalent thereof. The measurement values are average values obtained by changing the position measurement 3 in the width direction. The average value in the same production lot is an average value of 5 rolls.

On the other hand, the roll toilet paper is preferably wound in a length of 20 to 40m, and in this case, the winding density is preferably 0.20 to 0.30m/cm². The winding density here is a value calculated by winding length (m) ÷ actual cross-sectional area. The actual cross-sectional area is defined by { (roll diameter/2) × (core outer diameter/2) × (pi) } (unit: cm)²) The calculated value. That is, the area obtained by subtracting the area of the paper core opening end side from the area of the end face. The toilet paper of the present invention has a winding density of 0.20 to 0.28m/cm in the roll form²In the range of (3), the roll is remarkably soft when held in the hand. Note that the paper core outer diameter (paper core diameter) L3 is preferably set to the same general dimensions

In addition, the toilet paper of the invention preferably has a winding tightness of 1.8-3.0 mm. For measurement of the winding tightness (mm) (T0-TM) of the coil, "Portable compression tester KES-G5", manufactured by KATO TECH K.K.. The roll toilet paper TR was laid on a horizontal base formed of a steel plate so that its central axis was horizontal to have a compressed area of 2cm²The steel plate terminal of the circular flat surface of (2) is brought into contact with the center of the upper surface of the outer periphery of the roll body, and the contact state is set as a zero point, and the steel plate terminal is moved vertically downward at a speed of 10 mm/min from the zero point to compress the roll toilet paper. A compression load of 0.5gf/cm²The press-in amount was T0(mm) and the compression load was 50gf/cm²The amount of penetration in the case of the pressure application was TM (mm), and (T0-TM) (mm) was defined as the winding tightness (mm) of the coil. The greater the winding tightness (mm) of the coil, the greater the pressing force to 50gf/cm²The larger the depth of penetration, the bulkier the paper quality. That is, the fluffy feeling is satisfied. In addition, the winding length and the winding density described above can sufficiently achieve the winding tightness.

Further, the roll toilet paper of the present invention preferably has a compression Work (WC) of 3.5 to 5.5gf cm/cm². Amount of work done by compression(WC) is a steel plate terminal at 0.5gf/cm²Pressing into 50gf/cm after contacting with the roll²The larger the compression work amount (WC), the weaker the initial repulsive force at the time of press-fitting, so that the moment of grasping the roll feels soft, and then, when the compression load is pressed deeply to 50gf/cm at the time of normal grasping the roll²The coil was evaluated to be soft and fluffy.

In the toilet paper of the present invention, 50% by mass or more of the fibers are softwood kraft pulp having a long fiber length and containing lignin that has been digested with oxygen and has not been bleached with chlorine, and the bonding between fibers is moderately weak, so that the toilet paper is excellent in cushioning properties in the roll form and is easily perceived as having softness when held in the hand as described above.

Hereinafter, the effect of the toilet paper of the present invention will be further described with reference to examples.

Examples

Next, the toilet paper of the present invention was evaluated in terms of "softness", "bulky feeling", "thickness feeling", "breakage and strength during use" and "less paper powder during use" in reference examples, examples and comparative examples. The structure of the rolled toilet paper of each example, and the physical properties and composition of the toilet paper are shown in table 1 below. The reference example had the same general fiber composition as that of a product using chlorine-based bleached pulp, which is also called a bleached product, and had a higher LBKP as hardwood pulp than NBKP as softwood pulp. Comparative examples 5 to 6 are commercial products blended with unbleached pulp. The basis weight and the paper thickness of comparative examples 1 to 3 were particularly higher than those of examples. The embossings of the reference examples, and comparative examples 1 to 4 were the embossings of the pattern shown in fig. 1.

For the sensory evaluation, 18 test subjects actually used the rolled toilet paper of each example, and relative evaluation was performed on the items of "softness", "fluffy feeling", "thickness feeling", "breakage and strength at the time of use", and "less paper powder at the time of use" with reference to comparative example 6 (conventional product). In the evaluation, the score of comparative example 3 was set to 4 points (median), in the case of good to 7 points, and in the case of poor to 1 point, and the difference was set for each 1 point to perform the evaluation, and the average value was calculated and judged.

[ Table 1]

The examples of the present invention obtained extremely superior sensory evaluation results in terms of "softness", "fluffy feeling", "thickness feeling", "breakage and strength at the time of use", and "less paper dust at the time of use" as compared with comparative examples 5 to 7, which are conventional unbleached products. In addition, the same or higher sensory evaluation was obtained in terms of "softness", "fluffy feeling", "thickness feeling", "breakage and strength at the time of use", and "less paper powder at the time of use" as compared with the bleached product (reference example). That is, the examples of the present invention obtained softwood pulp having a long fiber length as 100 mass% of the raw material pulp and a high freeness, and obtained the same or higher sensory evaluation as that of a bleached product (reference example) using a papermaking raw material containing a large amount of LBKP having a short fiber length and having a low freeness. That is, the examples of the present invention had a sense of reassurance possessed by the unbleached product, and had the same quality as the bleached products (reference examples).

Further, example 1 was compared with comparative examples 1 to 4, and example 1 was evaluated to be particularly difficult to generate paper dust.

In addition, in the form of rolled toilet paper, the compression work of the example of the present invention is higher than that of the reference example and the comparative example, and softness is easily felt when the rolled toilet paper is held in a hand.

Thus, the toilet paper of the present invention has a thickness feeling which can be relieved in a situation where the toilet paper is used in a shower toilet, is sufficient in flexibility, is less likely to generate paper powder, is excellent in hydrolysis, and has a feeling of relief for a human body when used.

Description of the symbols

Roll diameters (diameters) of 1 … rolls of toilet paper, 10 … rolls of toilet paper, 20 … paper cores (tube cores), L1 … rolls of toilet paper, diameters of tube cores of L2 … rolls of toilet paper, widths of L3 … rolls of toilet paper,

concave portions

31,32 … and valley line portions 33 ….

Claims

1. A toilet paper is 3-4 layers of toilet paper and is characterized in that,

the toilet paper contains a cationic fatty acid amide softener,

the basis weight of the 1 layer is 10.5-12.5 g/m²，

the hydrolyzability is 10 seconds or less.