JP5317995B2 - Toilet paper for toilets with cleaning function - Google Patents

Description

  The present invention relates to a toilet paper suitable for use in a toilet with a cleaning function such as a warm water cleaning toilet seat.

In recent years, toilets with a cleaning function, such as a warm water cleaning toilet seat, are rapidly spreading, and an integrated toilet with a cleaning toilet seat and a toilet is also sold. And also in such a toilet with a washing function, it is usual to wipe off the water | moisture content attached to the local part with toilet paper.
However, ordinary toilet paper is highly water-soluble, and is easily broken by moisture adhering to the local area during washing, or the fibers loosen and adhere to each other, which makes it difficult to use in a toilet with a washing function.

For this reason, toilet paper has been developed in which the raw pulp is made by adding a cationic aldehyde-modified polyacrylamide copolymer to control the ease of loosening and the strength of the paper (Patent Document 1).
In addition, a toilet roll that is difficult to break when wet by water has been developed by adding a predetermined amount of a dispersant, a paper strength enhancer, and a sizing agent to raw pulp (Patent Document 2).
Furthermore, a technique has been developed that uses a wet paper strength enhancer for paper to maintain wet strength and emboss it to improve volume and softness (Patent Document 3).

Japanese Patent No.3512481 Japanese Unexamined Patent Publication No. 2006-320688 Japanese Unexamined Patent Publication No. 2005-168582

However, in the case of the technique described in Patent Document 1, a cationic aldehyde-modified polyacrylamide copolymer is added as a temporary wet paper strength agent. Since it is as small as about half, it is difficult to control the strength, the wet strength becomes too high, and it is difficult to properly manage the ease of loosening, and there is a problem in productivity.
Moreover, in the case of the technique described in Patent Document 2, the strength when wetted by water is maintained by delaying the water permeability, but there is a problem in that it is inferior to quick moisture wiping performance.
In the case of the technique described in Patent Document 3, it is difficult to control the strength of the wet paper strength enhancer within an appropriate range, and there is a problem that the ease of loosening varies.
Accordingly, an object of the present invention is to provide toilet paper for toilets with a cleaning function which is excellent in strength, softness and ease of loosening.

In order to solve the above problems, the present invention has found a toilet paper suitable for a toilet with a cleaning function by making a sheet (base sheet) from a raw material pulp having predetermined characteristics and blending ratio.
That is, the toilet paper with a cleaning function of the present invention is a toilet paper with a cleaning function in which two sheets having a basis weight per sheet of 15.0 g / m ² or more and 19.0 g / m ² or less are stacked. Te, the sheet is to papermaking and weight average fiber length 2 .5mm or more first pulp 70% by mass or more, the raw material pulp consisting of the following weight average fiber length 1.0mm or less of the second pulp 30% by weight The specific tensile strength of the first pulp is 18.0 (N · m / g) or more, the fiber roughness is 10 to 20 mg / 100 m, and the specific tensile strength of the second pulp is 18.0 (N · m / g). g) The fiber roughness is 12 mg / 100 m or less.

When pulp fibers come into contact with water, the hydrogen bond between the fibers is instantaneously lost and the bond strength is lost. However, if 70% by mass or more of the first long fiber pulp is added to increase the entanglement between the fibers, the wet strength of the sheet (web) can be maintained by physical entanglement even if the bond between the fibers is lost. Can do. In addition, this wet strength generally correlates with the dry strength of the pulp sheet. Therefore, by selecting pulp with appropriate strength (specific tensile strength of 18.0 (N · m / g) or more) and managing the basis weight per sheet within an appropriate range, Sufficient strength can be obtained to wipe off moisture adhering to the surface.
Conventionally, strength reinforcement by a wet paper strength enhancer has been carried out, but since the wet strength is manifested by adding a small amount of the wet paper strength enhancer, the ease of unraveling tends to fluctuate significantly. In the present invention, the strength of the sheet is improved without using such a paper strength enhancer.
The fiber roughness is a measure of the flexibility of the fiber, and the fiber roughness is expressed in terms of weight per unit length, and the smaller the value, the more slim the fiber. When compared at the same basis weight, a sheet made of pulp having a low fiber roughness has a higher number of fibers and a uniform texture than a sheet made of pulp having a high fiber roughness. Furthermore, since it is supple, it is suitable for the flexibility treatment by the crepe treatment and the manifestation of the effect. For this reason, the fiber roughness of the first pulp and the second pulp is regulated within the above range.

It is preferable that the first pulp has a freeness of 650 ml CSF or more, and the second pulp has a freeness of 500 ml CSF or more, and both the first pulp and the second pulp have a Klem water absorption of 80 mm or more.
Pulp freeness affects dewatering performance and energy intensity at the sheet making stage. The strength (for example, tensile strength) of the pulp improves the strength by increasing the hydrogen bonds between the fibers by fibrillating the fibers by the beating process. On the other hand, however, when the freeness decreases, the tension of the web increases and the paper quality becomes hard, the dewaterability decreases, and the energy intensity increases. The raw pulp has a higher freeness and higher strength in an unbeaten state, which is preferable in terms of operation and quality.
The Klem water absorption represents the water absorption characteristics of the pulp fiber web, and the higher the Klem water absorption, the higher the water absorption speed.

Each of the sheets is embossed at 5 to 15 pieces / cm ² , the embossed convex surfaces of each sheet, or the embossed convex surfaces and the embossed concave surfaces of each sheet are bonded to each other with a water-soluble glue, and the bonding area ratio of the bonded portion is It is preferably 5 to 20% per area of the sheet.
If it does in this way, while ply peeling can be prevented, a moderate volume feeling can be given.

The water-soluble paste is a paste having a solid content of 1 to 10% by mass, the main component of which is one or more selected from the group of methylcellulose, starch, and PVA, and the coating amount of the water-soluble paste is 0.1 to 0.8 g / may is m ^2.
If such a water-soluble paste is applied in the above-described range, the ease of loosening and the softness of the product are not impaired .

  According to the present invention, a toilet paper for a toilet with a cleaning function is obtained which is excellent in strength and water absorption, which is a water wiping performance after use of a washing machine, is excellent in feeling of use, and is easy to loosen after washing. It is done.

It is the top view and side view which show the structure of the testing machine for performing a wet friction test.

Toilet paper for toilets with a cleaning function according to an embodiment of the present invention is formed by stacking two sheets described below. Unless otherwise specified,% represents mass%.
The basis weight per sheet of this sheet is 15.0 g / m ² or more and 19.0 g / m ² or less.
The sheet has a weight average fiber length of about 2.5 mm or more and a specific tensile strength of 18.0 (N · m / g) or more of the first pulp of 70% by mass or more and a weight average fiber length of 1.0 mm or less. Further, a raw material pulp made of a second pulp having a specific tensile strength of 18.0 (N · m / g) or more and 30% by mass or less is made.
The weight average fiber length of the first pulp substantially corresponds to the softwood pulp, and the weight average fiber length of the second pulp substantially corresponds to the hardwood pulp.
When pulp fibers come into contact with water, the hydrogen bond between the fibers is instantaneously lost and the bond strength is lost. However, if 70% by mass or more of the first long fiber pulp is added to increase the entanglement between the fibers, the strength of the sheet can be wiped off by physical entanglement even if the bond between the fibers is lost. It is possible to ensure a sufficiently strong strength level. The strength level that can sufficiently withstand the action of wiping moisture is the strength at which the fiber on the surface of the sheet is not damaged or the sheet is not torn by the action of normal wiping (see the experimental results described later).
The specific tensile strength referred to here is the strength when dried by handsheet according to JIS P 8223 "Pulp-Handsheet for test-Physical property test method". In general, the strength at the time of drying has a positive correlation with the strength at the time of wetting, so that the strength at the time of drying can be used as a guide.

Moreover, in this invention, it is not necessary to mix | blend a paper strength enhancer with raw material pulp and to assist strength improvement. The wet paper strength agent acts sensitively even when added in a small amount of about 0.01% to pulp, and the variation in strength expression is large, which causes the sheet to be difficult to loosen when washed with water.
When the content of the first pulp in the sheet is less than 70% by mass, the ratio of the long fiber pulp is decreased, the surface strength of the sheet is decreased, and the fibers are easily peeled off when the moisture is wiped off. Furthermore, if the strength of the sheet is weak, it will be torn.
Further, when the basis weight per sheet is less than 15.0 g / m ² , the strength is similarly reduced. On the other hand, if the basis weight per sheet exceeds 19.0 g / m ² , the strength of the sheet is ensured, but the sheet becomes stiff and hard, and the ease of loosening when washed with water is impaired.

The fiber roughness of the first pulp is 10 to 20 mg / 100 m, and the fiber roughness of the second pulp is 12 mg / 100 m or less.
Fiber roughness is an important factor that determines strength, texture, and web softness. By controlling the fiber roughness within an appropriate range, a soft, well-textured, high-strength paper can be obtained. .
When the fiber roughness of the first pulp is less than 10 mg / 100 m, the fibers are too fine to fulfill the role as long fibers. When the fiber roughness of the first pulp exceeds 20 mg / 100 m, the fibers generally become thick and rigid, and the flexibility is impaired.
When the fiber roughness of the second pulp exceeds 12 mg / 100 m, in the case of hardwood pulp classified as a short fiber, the cell wall becomes thick and rigid, and the lacked product is soft and the product becomes dull or hard.

で表される。但し、K：最大繊維長さ、xi；繊維長さ、ni；長さxiを有する繊維の数である。
又、繊維粗度は、｛繊維重量/（測定本数×数平均繊維長）｝で表され、繊維の平均的な太さを表す。
なお、重さ平均繊維長及び繊維粗度は、所定の測定器（例えば、ローレンツェン・アンド・ベットレー（Lorentzen & Wettre）株式会社の製品名ファイバーテスター（Fiber Tester））を用いて測定することができる。
フリーネスは、ＪＩＳ Ｐ 8121に規格された「パルプのろ水度試験方法」で測定することができ、比引張り強さ、JIS P 8223に規格された「パルプ−試験用手すき紙−物理的特性の試験方法」により測定した値（坪量で補正した引っ張り強さの値）を用いることができる。 Here, the weight average fiber length is

It is represented by Where K: maximum fiber length, xi: fiber length, ni: number of fibers having length xi.
The fiber roughness is represented by {fiber weight / (measured number × number average fiber length)}, and represents the average thickness of the fiber.
The weight average fiber length and fiber roughness can be measured using a predetermined measuring instrument (for example, Fiber Tester, a product name of Lorentzen & Wettre Co., Ltd.). it can.
Freeness can be measured by the “Pulp Freeness Test Method” specified in JIS P 8121. Specific tensile strength, “Pulp-Handsheet for Testing-Physical Properties” specified in JIS P 8223 A value (a value of tensile strength corrected by basis weight) measured by “test method” can be used.

  As described above, the toilet paper for toilets with a cleaning function according to the embodiment of the present invention has two sheets having a relatively high basis weight per sheet, so that the water absorption speed per area is high, and the water absorption The amount increases. In addition, since it contains a lot of first pulp with a long average fiber length, the strength of the sheet (web) is high, and when wet and wiped, the paper scumming (attachment of wet toilet paper to the skin) is small, and the cleaning function Suitable for use in a toilet with a toilet. In addition, it has a high strength and is soft and easy to loosen.

In the toilet paper with a cleaning function according to the embodiment of the present invention, it is preferable that the first pulp has a freeness of 650 mlCSF or more and a second pulp has a freeness of 500 mlCSF or more. If the freeness of the first pulp is less than 650 ml CSF and the freeness of the second pulp is less than 500 ml CSF, the dewaterability in the paper making process is lowered, and the energy intensity is increased.
Moreover, it is preferable that the first pulp and the second pulp each have a Klem water absorption of 80 mm or more. If the pulp water absorption of each pulp is less than 80 mm, the water absorption speed is slightly lowered, and the degree of satisfaction is lowered because it cannot be wiped lightly and quickly.
The Krem water absorption is standardized in JIS P 8141 and can be measured by the “water absorption test method by the Krem method of paper and paperboard”, and indicates the water absorption absorbed by the strip of paper by capillary action.

In the toilet paper for toilets with a cleaning function according to an embodiment of the present invention, the sheet is embossed at 5 to 15 pieces / cm ² , and the embossed convex surfaces of the sheets or the embossed convex surfaces and the embossed concave surfaces of the sheets are It is preferably bonded with a water-soluble paste, and the bonding area ratio of the bonding portion is preferably 5 to 20% per area of the sheet.
A sheet obtained by bonding the embossed convex surfaces of each sheet together is referred to as pin-to-pin embossing, and a sheet formed by combining the embossed convex surface and the embossed concave surfaces of each sheet is referred to as a nested emboss.
In the case of an embossed pattern having the same shape, the above-mentioned adhesion area ratio is represented by (the area of the convex top per emboss (square centimeter)) × (the number of embosses per unit area (square centimeter)). The area of the top of the embossed convex surface is calculated from the design area of the embossed pattern.
In addition, the use of water-soluble glue improves the ease of loosening when poured into the toilet.
The bonding area affects the softness of the toilet paper and the ease of loosening. If the adhesion area ratio is less than 5% per sheet area, ply peeling tends to occur, the volume of toilet paper is lowered, and the touch is inferior. If the adhesion area ratio exceeds 20% per sheet area, the ease of loosening when poured into a toilet is poor. The ease of unraveling is 100 seconds or less in the JIS-P4501 “Toilet Paper” standard, but it is preferably 60 seconds or less for safety.

The water-soluble paste is an adhesive mainly comprising at least one selected from the group consisting of methylcellulose, starch, and PVA, and the water-soluble paste is a paste having a solid content of 1 to 10%, The coating amount is preferably 0.1 to 0.8 g / m ² . Examples of the methylcellulose adhesive include JW-5612 (manufactured by Sekisui Fuller), and examples of the PVA adhesive include JW-5606 (manufactured by Sekisui Fuller) and Kanebinol TV200 (manufactured by Henkel Technology Japan).

  It goes without saying that the present invention is not limited to the above-described embodiments, and extends to various modifications and equivalents included in the spirit and scope of the present invention.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated concretely, this invention is not limited to these examples of course.

The first pulp and the second pulp shown in Table 2 were blended, and a base sheet was made with an actual Ford linear tissue machine. Emboss this sheet (the area of the top of the embossed convex surface: 0.96 mm ² , the number of embossed: 12 / cm ² ), and methylcellulose adhesive (JW-5612, solid content 1-3%, manufactured by Sekisui Fuller) Using the two sheets, the embossed convex surface and the embossed concave surface of each sheet were adhered to each other (nested embossing) to produce toilet paper. In Comparative Example 1, a PVA adhesive (JW-5606 solid content: 6-10%) was used for embossing adhesion instead of the methylcellulose adhesive.
The resulting toilet paper was subjected to the following wet friction test (damage and tear) and hand feel evaluation.

Wet Friction Test A test machine shown in FIG. 1 was prepared, and test pieces obtained by stacking four sets of toilet paper obtained (2 ply sheets × 4) were attached and pulled for evaluation. This testing machine includes a friction plate (acrylic plate) 2, a weight 4 (weight 300 g, diameter 55 mm, height 16 mm), and a pulley 6. The friction plate 2 has a diamond-shaped continuous groove 5 mm at equal intervals. It is formed at intervals. The groove has a width of 1.5 mm and a depth of 1 mm (a top view of FIG. 1A).
The length of the test piece 10 was the perforation interval (114 mm), and the width was the toilet paper product width (114 mm). Then, after placing the test piece 10 on one end of the friction plate 2 and dripping 0.5 mL of water and infiltrating it, the weight 4 is placed on the test piece 10, a string 12 is attached to one end of the test piece 10 with a clip 11, and a pulley. 6 was pulled by a distance of 300 mm on the friction plate 2 at a pulling speed of 10 mm / sec with a tensile tester (Tensilon) not shown (side view of FIG. 1B). This test was repeated 5 times, and it was visually observed whether the sheet was torn and whether the sheet was partially peeled off, and evaluated according to the following criteria.

Evaluation criteria of wet friction test (smoke) ◎: Smoke is not seen at all (5 tests)
○: Slight blemishes are seen on one sheet on the surface, but do not peel off from the sheet (○ within 2 times out of 5 tests, △ if 3 times or more)
Δ: Slight blemishes are observed on the two sheets on the surface, but they are not loosened (evaluated if applicable up to 2 out of 5 tests, but x if 3 or more times)
X: Scratch occurred remarkably in 2 sheets or more (evaluated if applicable even once out of 5 times)
Evaluation criteria for wet friction test (break) ◎: Not broken at all (5 tests)
○: One sheet on the surface is slightly broken (5 mm or less) (Evaluation is applicable if up to 2 times out of 5 tests, but △ if 3 times or more)
Δ: Two sheets on the surface are broken (less than 10 mm) (Evaluation is true even if one of the five tests is true, and x if it is two or more times)
×: Breaking occurred on 3 sheets or more (Evaluation if applicable even 1 out of 5 times)

  Table 1 shows the results of the wet friction test and the results of the feeling of use in which the toilet paper test piece used in this test was used on a monitor of four men and women. There are individual differences in the method of use, and there are variations in the evaluation. However, if the wet friction test shows an evaluation of ◯ or higher, it is judged that the actual feeling of use is satisfactory.

Hand feel is a touch sensory test by 5 panelists on the obtained tissue paper (very soft: 5 points, moderately soft: 4 points, normal: 3 points, slightly hard: 2 points, hard: 1 point) And evaluated. The evaluation criteria for hand feel were as follows.
◎: Average of five or more 4.5 points ○: Average of five or more 3.5 or more △: Average of five or less 3.5 or less ×: Average of five or less than 3.0

In addition, various properties of the pulp were measured. The weight average fiber length and fiber roughness of the pulp were measured using a measuring instrument (product name Fiber Tester, Lorentzen & Wettre Co., Ltd.).
Freeness is measured by “Pulp Freeness Test Method” specified in JIS P 8121, and specific tensile strength is “Pulp-Handsheet for Testing-Test Method for Physical Properties” specified in JIS P 8223. ”(Value of tensile strength corrected by basis weight) was used. The Krem water absorbency was measured by the “water absorption test method by the Krem method for paper and paperboard” standardized in JIS P 8141.
The water absorption rate (seconds) is about 0.1 mm of distilled water with a temperature of 20 ± 1 ° C dropped from a height of about 10 mm on a two-ply sheet, and when the water droplet touches the sheet, it is completely absorbed by the sheet and reflected. The time until the light disappeared was measured in units of 0.1 second. . The ease of loosening (seconds) was determined by the ease of loosening test described in JIS P-4501 “Toilet paper”.

  Further, a sheet was made using a pulp slurry containing the first pulp and the second pulp shown in Table 2 in an actual Ford linear tissue machine, and the tensile strength of the sheet was measured according to JIS P 8113 “Paper and paperboard— It was measured according to “Test Method for Tensile Properties” (see “Evaluation” column in Table 2).

  The obtained results are shown in Table 2.

As is clear from Table 2, in each example, the tissue paper was easily loosened, the hand feel was excellent, the wet friction test was good, and it was suitable for use in a toilet with a cleaning function.
On the other hand, in the case of Comparative Example 1 in which the basis weight per sheet was less than 15.0 g / m ² , the wet friction test was inferior and it was easily broken by moisture. In addition, since the amount of glue is large, it feels a little stiff and is not suitable for use in a toilet with a cleaning function due to poor ease of loosening.
In the case of Comparative Example 2 in which the basis weight per sheet exceeded 19.0 g / m ² , the sheet became hard and unpleasant to the touch and inferior in ease of unraveling.
In the case of Comparative Example 3 in which the blending amount of the first pulp in the sheet is less than 70% by mass, the ratio of the long fiber pulp is decreased, the surface strength is lowered, the fiber is loosened, and the fiber having a high fiber roughness Since the ratio of was increased, the hand feel was inferior (hardened).

Claims (5)

Toilet paper for toilets with a cleaning function, consisting of two sheets with a basis weight per sheet of 15.0 g / m ² or more and 19.0 g / m ² or less,
It said sheet has a weight average fiber length 2 .5mm or more first pulp 70 wt% or more, and papermaking raw material pulp consisting of weight average fiber length 1.0mm or less following the second pulp 30% by weight,
The specific tensile strength of the first pulp is 18.0 (N · m / g) or more, and the fiber roughness is 10 to 20 mg / 100 m.
Toilet paper for toilets with a cleaning function, wherein the second pulp has a specific tensile strength of 18.0 (N · m / g) or more and a fiber roughness of 12 mg / 100 m or less.   The toilet paper for toilets with a cleaning function according to claim 1, wherein the sheet has a first pulp freeness of 650 ml CSF or more and a second pulp freeness of 500 ml CSF or more.   The toilet paper for toilets with a washing function according to claim 1 or 2, wherein both the first pulp and the second pulp have a Krem water absorption of 80 mm or more. Each of the sheets is embossed at 5 to 15 pieces / cm ² , the embossed convex surfaces of each sheet, or the embossed convex surfaces and the embossed concave surfaces of each sheet are bonded with water-soluble glue,
The toilet paper for a toilet with a cleaning function according to any one of claims 1 to 3, wherein an adhesion area ratio of the adhesion portion is 5 to 20% per area of the sheet. The water-soluble paste is a paste having a solid content of 1 to 10% by mass, the main component of which is one or more selected from the group of methylcellulose, starch, and PVA, and the coating amount of the water-soluble paste is 0.1 to 0.8 g / m ² a is 4. cleaning function toilet toilet paper according.

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