CN112911977B

CN112911977B - Toilet paper

Info

Publication number: CN112911977B
Application number: CN201980069393.2A
Authority: CN
Inventors: 保井秀太; 岩崎穣
Original assignee: Daio Paper Corp
Current assignee: Daio Paper Corp
Priority date: 2018-11-30
Filing date: 2019-11-22
Publication date: 2022-11-11
Anticipated expiration: 2039-11-22
Also published as: JP6689944B1; JP2020081795A; CN112911977A; EP3865035A1; KR102644625B1; BR112021010204A2; KR20210095857A; WO2020110923A1; US20210401242A1; EP3865035A4

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 12.5-15.5 g/m ² 80 to 100% by mass of the fibers are softwood kraft pulp which is oxygen-digested and not chlorine-bleached, and contain a cationic fatty acid amide softener, wherein the thickness of 1 layer is 120 to 150 μm, the thickness of the entire toilet paper is 400 to 600 μm, and the hydrolyzability is 10 seconds or less.

Description

Toilet paper

Technical Field

The invention relates to toilet paper.

Background

With the spread of a shower toilet also called a toilet with a cleaning function, there is a demand for toilet paper suitable for use in the shower toilet (patent document 1).

Multi-ply products such as 3-ply or 4-ply products, which are comfortable to the consumer when using, are considered ideal for toilet paper suitable for toilet showers.

Incidentally, toilet paper is usually 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 contains a large amount of hardwood-derived pulp which is likely to improve flexibility and surface properties.

Further, in order to improve whiteness, pulp as a fiber raw material is bleached with chlorine-based bleaching agents such as chlorine, chlorine dioxide, and sodium hypochlorite, but for consumers who pay attention to the sense of reassurance to the human body and the consideration of the environment, a product in which the environment and the like are considered using pulp without using a chlorine-based bleaching agent as a raw material is also desired.

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 to be blended in order to make the paper more flexible, but the hydrolyzability is easily deteriorated by increasing the amount of hardwood pulp to be blended. 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.

Accordingly, a main object of the present invention is to provide a toilet paper which has a thickness feeling which is secure in a use situation in a toilet bowl, is sufficient in flexibility, is excellent in hydrolyzability, and has a secure feeling to a human body in use.

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,

80 to 100% by mass of the fibres are softwood kraft pulp digested with oxygen and not chlorine bleached,

comprises a cationic fatty acid amide-based softening agent,

the basis weight of the 1 layer is 12.5-15.5 g/m ² ，

The paper thickness of 1 layer is 120-150 μm, the paper thickness of the toilet paper is 400-600 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 which is relieved when used in a shower toilet, is sufficiently flexible, has excellent hydrolyzability, and is relieved to the human body when used.

Drawings

Fig. 1 is a plan view of an emboss according to 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 are stacked. 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. In addition, if the number of layers is 5 or more under the conditions of basis weight and paper thickness of 1 layer in the present invention 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 12.5g/m ² Above 16.2g/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 touch and can easily exhibit hydrolyzability.

On the other hand, in the toilet paper of the present invention, 80 to 100% by mass, particularly 100% by mass of the constituent fibers are softwood kraft pulps which have been oxygen-digested and not chlorine-bleached. More specifically, the kraft softwood pulp, also referred to as NOKP, is produced by continuous oxygen cooking in a continuous cooking vessel, and is not particularly subjected to subsequent bleaching treatment with a chlorine-based bleaching agent. Here, KP (kraft pulp) used in toilet paper includes bleached KP and unbleached KP, the unbleached KP containing a large amount of lignin. The kraft softwood pulp of the invention is not bleached with a chlorine-based bleaching agent, but is digested with oxygen (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 kraft softwood pulp described above for the present invention.

The toilet paper of the present invention contains 80 to 100 mass% of softwood kraft pulp which has not been bleached with a chlorine-based bleaching agent but has been delignified by oxygen cooking. That is, since the softwood kraft pulp is produced as a main fiber material, particularly as a whole fiber material, the softwood kraft pulp has a feeling of reassurance to the human body when used, and is environmentally friendly. In particular, since toilet paper containing 80 to 100 mass% of the softwood kraft pulp is light brown, it is also visually easy to give an impression like natural materials which have not been chemically treated, and it has a soft impression, so that the 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 wood pulp which is not delignified at all as a raw material, the wood pulp is easy to exhibit flexibility and also easy to have sufficient strength. Further, hardwood kraft pulp, which is easily reduced in hydrolyzability, is less than 20% by mass, particularly 0% by mass, and thus the hydrolyzability is also easily improved.

In addition, because 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, softwood kraft pulp is derived from conifers and therefore has a longer fiber length than hardwood pulp, and combines with the effect of lignin on making the fibers less dense, thereby providing pulp having excellent cushioning properties.

The toilet paper of the present invention comprises 80 to 100 mass% of the softwood kraft pulp, and has a basis weight of 12.5 to 16.0g/m in 1 layer ² . More preferably, the basis weight of 1 layer is 12.7 to 15.8g/m ² . The basis weight according to the present invention is obtained by a basis weight measuring method according to JIS P8124 (1998). By containing 80 to 100 mass% of the above softwood kraft pulp and making the basis weight of 1 layer slightly lower 12.5 to 15.5g/m ² 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, easily exhibits flexibility, and gives a feeling of reassurance to the human body when used. Here, the other pulp fibers constituting the toilet paper of the present invention are not necessarily limited. It can be virgin pulp or waste paper pulp. 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 may be determined in the range of 0 or more and less than 20 mass%. The type of used paper pulp is not particularly limited, but used paper pulp made from milk carton waste paper or high-quality waste paper is particularly preferable. Since a large amount of hardwood kraft pulp (LBKP) derived from a raw material is blended in these pulps, the paper strength is easily expressed.

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 toilet paper is coated with the moisturizing agent, the toilet paper feels sticky and moist 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 is added with a softening agent and a softening humectant which are added during the paper making process and determine the flexibility and paper strength of the base paper itself. The softener contained in the toilet paper of the present invention is a cationic fatty acid amide-based softener. The toilet paper of the present invention preferably contains the cationic fatty acid amide-based softener. The cationic fatty acid amide-based softening agent has no effect of lowering due to the inclusion of lignin, and also functions to coat the fiber surface. Therefore, even when the pulp containing lignin is compounded at a high ratio, the surface is smooth, the stiff feeling 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 when the fixation rate is 50 to 60%, the amount to be added during production may be 0.5 to 4.0 kg/ton of pulp.

In addition, the toilet paper of the invention is preferably 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.

Here, the toilet paper of the present invention may 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 what is called a single embossing, which is imparted in a layer-by-layer state.

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 gradually and gently becomes arcuate in such a manner 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 excrement wiping property.

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 field area of 24mm × 18 mm. The magnification and the viewing area can 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-described software is used to obtain the distribution of the emboss depths (measurement cross-sectional curves) in 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 depth Min is obtained by obtaining a "profile curve Q2" of an image portion (Y portion in the figure) displayed in a cross-sectional view, by using 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 determining the minimum values of 2 recess edge points P1, P2 which are convex upward and most strongly curved, and the minimum values sandwiched between the recess edge points P1, P2, among 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 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 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 an ONESHOT 3D measurement microscope VR-3200 or an equivalent instrument thereof and image analysis software "VR-H1A" or an equivalent software thereof, 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.

On the other hand, in the toilet paper of the present invention, the thickness of 1 layer is 120 to 150 μm, and the thickness of the whole toilet paper is 400 to 600 μm. By setting the paper thickness in this range, flexibility is improved. In the method for measuring the paper thickness of toilet paper, a test piece was subjected to sufficient humidity conditioning (usually about 8 hours) under the conditions of JIS P8111 (1998), and then measured 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 to place the sample on the test bed, the plunger was slowly lowered, and the number of meters (gauge) at that time was read. 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. The plunger is simply placed and not depressed during the assay. The terminal of the plunger was made of metal, and a circular plane having a diameter of 10mm was brought into contact with a plane of paper 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, in the measurement of the paper thickness, it is conceivable that the embossments (recesses) are crushed, but the paper thickness of the present invention is a value measured including such crushing, and such crushing is negligible. In the paper thickness measurement, the difference in paper thickness due to collapse of the concave portion was negligible.

In addition, the toilet paper of the invention has hydrolysis performance within 10 seconds and is very quick. This is because 80% by mass or more, particularly 100% by mass of the constituent fibers is 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 is the degree of looseness. The rotor is a disc-shaped rotor with the diameter of 35mm and the thickness of 12 mm.

The toilet paper of the present invention preferably has a Canadian Standard freeness of the papermaking raw material of 650cc or more. When the canadian freeness of the paper-making raw material is 650cc or more, the pulp fibers are hardly beaten or are fibers as a raw material without beating, and hence the hydrolyzability is easily made more excellent.

Here, the dry tensile strength of the toilet paper of the present invention in the machine direction is preferably 400cN/25mm or more and 900cN/25mm or less. The dry tensile strength in the transverse direction is preferably 200cN/25mm or more and 450cN/25mm or less. If the range is within this range, sufficient durability can be obtained.

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 distance between the chucks was set to 100mm, and the stretching 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 (digital value) at the time of paper breakage was read. 5 sets of samples were prepared in the longitudinal and transverse directions, and the average of the measurements was defined as the dry tensile strength in each direction. In the case of the product, the dry tensile strength was measured by stacking a plurality of sheets in accordance with the number of layers of the product. The dry tensile strength of the base paper was also measured by stacking a plurality of base papers according to the number of layers of the product.

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 25cN/25mm to 50cN/25 mm. 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 TG-200N and equivalent instruments were used as the testing machine. The distance 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 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 9.5. If the MMD is less than 7.5, the surface is excessively slippery and the wiping property is reduced; if the amount exceeds 9.5, 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 a direction substantially equal to the direction in which the tension was applied, and the friction coefficient at that time was measured using a friction-sensitive tester KES-SE (manufactured by Katotech corporation) or an equivalent device. 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 1.8cN/100mm or more and 3.5cN/100mm or less. Softness is one of the indicators of softness, and it is considered that the lower the value, the softer the softness. For paper towels or toilet tissue, softness of 1.0cN/100mm or less is considered to be sufficiently soft. 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 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. Softness is expressed in terms of cN/100mm in some cases, although it has no unit.

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 softwood kraft pulp having a long fiber length at a high content of 80 mass% or more, particularly 100 mass%, entanglement between fibers can be ensured, and sufficient strength can be obtained. Further, the lignin is contained, so that the hydrolysis is excellent. 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, 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 sodium carboxymethyl cellulose, calcium carboxymethyl cellulose, and zinc carboxymethyl cellulose as salts thereof.

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, as shown in fig. 3, the toilet paper of the present embodiment is preferably in the form of a roll toilet paper in which a strip toilet paper 10 is wound into a roll on a paper core (also referred to as a core) 20.

The roll diameter L2 (diameter) of the roll toilet paper of the present invention is preferably 110 to 115mm. 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 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 value is an average value obtained by changing the site 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 roll density is preferably set to 0.20 to 0.30m/cm ² . The roll density here is a value calculated by a roll 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 wound in the roll form to have a density of 0.20 to 0.28m/cm ² The range of (3) is such that flexibility is remarkably felt when the roll is held in the hand with the peripheral surface. Note that, the paper core outer diameter (paper core diameter) L3 is preferably the same as the general size

In addition, the toilet paper of the present invention preferably has a winding tightness of 1.8 to 2.2mm. For measurement of the winding tightness (mm) (T0-TM) of the coil, a "Portable compression tester KES-G5" manufactured by KATO TECH K.K. was used. 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 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 can be set to the winding tightness sufficiently。

Further, the rolled toilet paper of the present invention preferably has a compression Work (WC) of 3.6 to 4.6gf 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 coil was evaluated to be soft and fluffy.

In the toilet paper of the present invention, 80 to 100% by mass 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 since the fibers are weakly bonded to each other, the toilet paper has excellent cushioning properties in the roll form and is easily provided with 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, regarding examples and comparative examples of the toilet paper of the present invention, "flexibility", "bulky feeling", "thickness feeling", "breakage and strength at the time of use" were evaluated in terms of sensory properties.

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.

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", "bulky feeling", "thickness feeling", "breakage during use, and strength" with reference to comparative example 3 (conventional product). In the evaluation, the score of comparative example 3 was 4 points (median), when the score was good, the score was 7 points, when the score was poor, the score was 1 point, and the score was calculated by setting a difference for each 1 point, and the average value was calculated and judged.

[ Table 1]

The examples of the present invention gave excellent results in sensory evaluation. In addition, particularly excellent results were obtained with respect to the hydrolyzability. In addition, compared with comparative example 1 in which the winding density was substantially the same, excellent measurement results were obtained in terms of winding tightness and compression work amount (WC) at the time of making a coil. Further, with respect to the strength, a measurement result was obtained in which sufficient strength was secured so as not to be broken during use.

Thus, the toilet paper of the present invention has a thickness feeling which can be relieved in a situation where it is used in a toilet bowl, is sufficient in flexibility, is excellent in hydrolyzability, and has a feeling of relief for the human body when used.

Description of the symbols

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

Claims

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

80 to 100% by mass of the fiber is softwood kraft pulp which has been oxygen-digested and has not been chlorine-bleached, and the toilet paper contains a cationic fatty acid amide softener,

the basis weight of 1 layer was 12.5g/m ² ～15.5g/m ² ，

The thickness of 1 layer of paper is 120-150 μm, the thickness of the whole toilet paper is 400-600 μm,

the hydrolyzability is 10 seconds or less,

the toilet paper does not contain a paper strengthening agent.