CN113330158B

CN113330158B - Toilet paper

Info

Publication number: CN113330158B
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: 2022-11-15
Anticipated expiration: 2040-02-12
Also published as: EP3907328A1; WO2020179379A1; US20220127790A1; KR20210134645A; JP2020141870A; CN113330158A; EP3907328B1; JP7175801B2; 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. [ means for solving the problems ]]The toilet paper is 3-4 layers of toilet paper, and the basis weight of 1 layer is 10.5-12.5 g/m ² 50 to 100% by mass of the fiber is softwood kraft pulp which is not bleached by chlorine but is oxygen-digested, comprising a cationic fatty acid amide-based softener, and 1 layer of the kraft pulp has a paper thickness of 80 to 100 μm, a paper thickness of 320 to 400 μm based on the whole toilet paper, and a hydrolyzability of 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 shower toilet, 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 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 dust, has excellent hydrolysis properties, and has a feeling of relieved feeling to 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% by mass of the fibers are softwood kraft 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/m ² ，

The paper thickness of 1 layer is 80-100 μm, the paper thickness of the 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 scene of use in a shower toilet, is sufficiently flexible, is less likely to generate paper powder, has excellent hydrolysis properties, 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 a process of measuring the embossing depth according to 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 sense 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/m ² Above 12.5g/m ² The following. Preferably 10.6g/m ² Above and below 12.4g/m ² More preferably 10.7g/m ² Above 12.3g/m ² The 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. To say thatIt is to be noted that the basis weight of the present invention is obtained by the basis weight measuring method according to JIS P8124 (1998).

On the other hand, in the toilet paper of the present invention, 50 mass% or more of the main fibers constituting the fibers need to be conifer sulfate pulp that has been digested with oxygen and has not been bleached with chlorine. 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 kettle, and is not particularly 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 softwood kraft pulp is light brown, and is also likely to have an impression of natural materials that have not been chemically treated in appearance, and has a soft impression, so that the purchaser has 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 bonding. 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 may be used, and waste paper pulp may 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 digested with oxygen and not bleached with chlorine and has a basis weight of 1 ply as low as 10.5 to 12.5g/m ² And 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 used as the external additive of the invention is polyhydric alcohols, and at least comprises glycerin, diglycerin, propylene glycol, 1, 3-butanediol 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 softening agent that determines the flexibility and paper strength of the base paper itself, which is added during paper making. 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 the reaction of a polyalkylene polyamine and a monocarboxylic acid and epihalohydrin is added, it is preferably added by mixing 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 softening agent is not particularly limited, and the amount to be added during production may be 0.5 to 4.0 kg/ton of pulp when the fixation rate is 50 to 60%.

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

In the toilet paper of the invention, the paper thickness of 1 layer is 80-100 μm, and the paper thickness of the whole toilet paper is 320-400 μm. 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 gauge) "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 70gf. The paper thickness was an average value obtained by 10 measurements. Here, although it is assumed 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 can be ignored. 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 of a general papermaking stock. 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 without adding the above softener, the softener 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 softness is excellent and the fluffy feeling is also good. Moreover, paper dust is extremely difficult to produce. Further adjustment of the paper thickness can be further carried out by the creping ratio.

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 which is given in a layer-by-layer state called single-sided embossing.

In a preferred embossed pattern of the present invention, the area of the depressions is 1.0 to 2.5mm ² The density is 5.0 to 50 pieces/cm ² The embossing depth is 0.05-0.5 mm. The toilet paper has improved flexibility, and also has improved flexibility in a rolled state as in roll toilet paper, and is easily felt by consumers when the consumers hold the toilet paper in their hands. In particular, as shown in fig. 1, square recesses 31 (fig. 1A) having a bottom face of a diagonal L4 × a diagonal L4=1.0 to 1.5 × 1.0 to 1.5mm or recesses 32 of an approximate square (fig. 1B) extending outside diagonal lines of four corners of the square are arranged in a lattice shape at a center interval L5 of 4.5 to 5.5mm over the entire paper surface at an arrangement angle of 45 ° with respect to the width direction, 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 such 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 is described with reference to fig. 2, and the above software is used to obtain the distribution of emboss depths (measurement cross-sectional curves) at a line segment Q1 crossing the longest portion of the peripheral edge of one emboss (concave portion) 40 in an image portion (X portion in the figure) displayed in a plan view. The wavelength ratio λ c: the minimum value of the minimum value Min of the depth is obtained by obtaining a "profile curve Q2" of an image portion (Y portion in the figure) displayed in a cross-sectional view, which is a component having a short surface roughness 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 obtaining 2 recess edge points P1 and P2 which are convex upward and are most strongly curved, and the minimum value sandwiched between the recess edge points P1 and P2, of the obtained "profile curve Q2". 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 = maximum Max-minimum Min. 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 2 recess edge points P1, P2 that are convex upward and most strongly curved 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 performed for any 10 embossings on the surface of the toilet paper, and the average value thereof was defined 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 mass% or more, preferably 80 mass% or more, and particularly 100 mass% of the constituent fibers are softwood kraft pulp containing lignin, and the fibers tend to loosen. 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 stop watch was stopped at the time when the rotation 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 a 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 the chucks was set to 100mm, and the drawing speed was set to 100mm/min. The measurement was carried out by 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 a digital value, this digital 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 multilayered, measurement is performed in a multilayered state as it is. The tensile testing machine TG-200N and equivalent instruments were used as the testing machine. The interval between the chucks was set to 100mm, and the drawing speed was set to 50mm/min. As the test piece, a test piece cured (curing) for 10 minutes by a drier at 105 ℃ was used. 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 central portion of the test piece with a flat-head brush containing water at a width of about 10mm, and immediately after that, a tensile load was applied to the paper piece in the vertical direction, and an indication value (digital 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. 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 (moving distance =2 cm) is 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 0.25 mm) 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 measurement 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 in size, and the gap was 5mm. 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 particular, from the viewpoint of a feeling of distraction to the user, it is preferable not to contain a paper strengthening agent. 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 agent, and further, hydrolyzability can be improved.

In the toilet paper of the present embodiment, as described above, the dry strength agent or the wet strength agent is preferably not used, but 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 roll diameter L2 (diameter) of the roll toilet paper of the invention is preferably 110 to 115mm. The roll diameter of the roll toilet paper is specified 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 of the invention is 110-115 mm, which is a size 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 device. 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/cm ² . 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 is in the roll form, if the roll density is 0.20 to 0.28m/cm ² In 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 size as the general size

In addition, the toilet paper of the present invention preferably has a winding tightness of 1.8 to 3.0mm. For measuring the winding tightness (mm) (T0-TM) of the roll, "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 and had a compressed area of 2cm ² The 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/cm ² The pressing amount in the case of pressing was T0 (mm), and the compression load was 50gf/cm ² The pressing amount in the case of pressing is TM (mm), and (T0-TM) (mm) is defined as the winding tightness (mm) of the roll. The greater the winding tightness (mm) of the coil, the greater the pressing force to 50gf/cm ² The 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 rolled toilet paper of the present invention preferably has a compression Work (WC) of 3.5 to 5.5gf cm/cm ² . The compression work amount (WC) was set at 0.5gf/cm for the steel plate terminal ² Pressing into 50gf/cm after contacting with the roll ² The 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 roll ² The roll was evaluated as 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 which has been digested with oxygen and not bleached with chlorine, and the bonding between fibers is moderately weak, and therefore, the toilet paper is excellent in cushioning properties in the roll form and is easily perceived to be soft 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 in reference examples, examples and comparative examples was evaluated for "softness", "bulky feeling", "thickness feeling", "breakage and strength during use" and "less paper powder during use" in terms of sensory evaluation. The structure of the toilet paper rolls of the examples, 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 commercially available products in which unbleached pulp was blended. The basis weight and paper thickness of comparative examples 1 to 3 are particularly higher than those of examples. The embossings of the reference example, and comparative examples 1 to 4 were 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 (center value), in the case of good to 7, and in the case of poor to 1, and the score was set for each 1 score to evaluate, 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 extremely 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

1 \ 8230, roll toilet paper 10 \ 8230, toilet paper 20 \ 8230, paper core (tube core) L1 \ 8230, roll diameter (diameter) and L2 \ 8230of roll toilet paper, diameter and L3 \ 8230of tube core of roll toilet paper, width and 31,32 \ 8230of roll toilet paper, concave part and 33 \ 8230, and valley line part.

Claims

1. A toilet paper is a toilet paper with 3 layers to 4 layers 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/m ² ，

the hydrolyzability is 10 seconds or less.