KR102151693B1 - Sanitary thin paper and absorbent article using same - Google Patents

Abstract

It provides a sanitary foil paper having an excellent deodorizing function, and an absorbent article using the same. Containing ions of one or more metal elements selected from the group Ag, Au, Pt, Pd, Ni, Mn, Fe, Ti, Al, Zn, and Cu for oxidized cellulose fibers having a carboxyl group or carboxylate group on the surface. It is a sanitary foil containing cellulose fibers.

Description

Sanitary tissue paper and absorbent article using the same {SANITARY THIN PAPER AND ABSORBENT ARTICLE USING SAME}

The present invention relates to a sanitary foil paper having a deodorizing function, and an absorbent article using the same.

It has been practiced in various ways to impart a deodorant function to sanitary tissue paper such as tissue paper, toilet paper, and hand towel. For example, a technique for applying a drug having a deodorant function to a base paper has been disclosed (Patent Documents 1 and 2). In addition, a technology for imparting a deodorant function to the paper itself is disclosed by supporting the zeolite inside the cellulose fibers while simultaneously supporting Ag, Cu, etc. in the zeolite, and papermaking the cellulose fibers ( Trade name Cellgaia (registered trademark)), Patent Document 3).

Further, today, there is a very high demand for imparting a deodorizing function to absorbent articles such as paper diapers, mild incontinence products, and dog sheets. As such an absorbent article, a structure in which the absorbent core is wrapped with a carrier sheet (core wrap sheet) coated with a deodorant, and the entire outer layer sheet is wrapped is disclosed (Patent Document 4). Then, a technique in which the cellulose fibers of Patent Document 3 are paper-papered to form a deodorizing (odor removed) sheet and disposed between the absorbent core of an absorbent article and a back sheet is disclosed (Patent Document 5).

Japanese Patent Laid-Open Publication No. 2003-325372 Japanese Special Publication No. 2010-511806 Japanese Patent Publication No. 4149066 Japanese Patent Laid-Open Publication No. 2004-89322 Japanese Patent Laid-Open Publication No. 2008-48775

However, when a drug having a deodorant function is coated on a base paper, the bonding between the pulp fibers is weakened, resulting in the generation of paper powder, or the original strength, absorbency, and touch of the sanitary foil may be impaired. In addition, there is a concern that drugs that are free or eluted from the sanitary foil may irritate the skin.

On the other hand, in the case of the technique described in Patent Document 3, there is a problem that the zeolite is physically supported in the cellulose fibers, so that the zeolite is easily removed and the deodorizing function is not sufficient. Further, in the case of the technique described in Patent Document 3, the fiber is deformed and damaged due to a reaction when the zeolite or the like is supported on the cellulose fiber, resulting in shortening. For this reason, when the core wrap sheet is produced by papermaking these cellulose fibers, the bond between the fibers is weakened, and lumping or tearing is liable to occur in the core wrap sheet similarly to the above.

Accordingly, an object of the present invention is to provide a sanitary foil paper having an excellent deodorizing function and an absorbent article using the same.

In order to solve the above problems, the sanitary foil paper of the present invention, Ag, Au, Pt, Pd, Ni, Mn, Fe, Ti, for oxidized cellulose fibers having a carboxyl group or a carboxylate group on the surface. It includes metal ion-containing cellulose fibers formed by containing ions of one or more metal elements selected from the group Al, Zn, and Cu.

It is preferable that the content of the metal ions in the oxidized cellulose fiber is 10 to 60 mg/g, and particularly preferably 15 to 50 mg/g.

The absorbent article of the present invention is an absorbent article having an absorbent core, a core wrap sheet covering or laminated to the absorbent core, and a liquid-permeable outer layer sheet covering at least one side of the core wrap sheet, The core wrap sheet is the above-described sanitary foil paper.

According to the present invention, it is possible to obtain a sanitary foil paper having an excellent deodorizing function and an absorbent article using the same.

1 is a perspective view showing the appearance of an absorbent article according to an embodiment of the present invention,
2 is a cross-sectional view taken along line AA in FIG. 1.

The sanitary foil paper according to the embodiment of the present invention is 1 selected from the group of Ag, Au, Pt, Pd, Mn, Fe, Ti, Al, Zn and Cu for oxidized cellulose fibers having a carboxyl group or a carboxylate group on the surface. It includes metal ion-containing cellulose fibers formed by containing ions of more than one type of metal element.

This metal ion-containing cellulose fiber can be obtained by bringing a metal compound aqueous solution into contact with an oxidized cellulose fiber having a carboxyl group or a carboxylate group introduced into the surface of the cellulose fiber. In addition, as a method of manufacturing a sanitary foil according to an embodiment of the present invention, in addition to the method of contacting the aqueous metal compound solution to a sheet made of a sheet of oxidized cellulose fiber, metal ions are previously contained in the oxidized cellulose fiber. A method of making a raw material containing a metal ion-containing cellulose fiber can be illustrated.

The oxidized cellulose fibers can be produced by oxidizing cellulose fibers such as wood pulp using an N-oxyl compound as a catalyst. By this oxidation reaction, the primary hydroxyl group at the C6 position of the glucopyranose ring on the cellulose surface is selectively oxidized, and oxidized cellulose fibers having a carboxyl group or a carboxylate group on the surface are obtained. Natural cellulose is preferable as the raw material cellulose. It is preferable to carry out the oxidation reaction in water. The concentration of the cellulose fibers in the reaction is not particularly limited, but 5% by mass or less is preferable. The amount of the N-oxyl compound should be about 0.1 to 4 mmol/L based on the reaction system. For the reaction, a known co-oxidizing agent may be used. Examples of the co-oxidizing agent include hypohalogenic acid or a salt thereof. The amount of the co-oxidizing agent is preferably 1 to 40 mol with respect to 1 mol of the N-oxyl compound.

The reaction temperature is preferably 4 to 40°C and more preferably room temperature. The pH of the reaction system is preferably 8 to 11. The degree of oxidation can be appropriately adjusted depending on the reaction time and the amount of the N-oxyl compound.

The oxidized cellulose fiber thus obtained has acid groups on its surface and almost no acid groups inside. This is considered to be because the oxidizing agent is difficult to diffuse into the fiber because the cellulose fiber is crystalline.

The carboxyl group refers to a group represented by -COOH, and the carboxylate group refers to a group represented by -COO-. The counter ion of the carboxylate group in producing the oxidized cellulose fiber is not particularly limited. Then, a metal ion to be described later is substituted with the counter ion to ionic bond with a carboxylate group. Moreover, it is thought that a carboxyl group coordinates with metal ions, such as a copper ion, for example. It is also called an "acid group" by combining a carboxyl group or a carboxylate group.

The content of the acid group can be measured by the method disclosed in paragraph [0021] of Japanese Unexamined Patent Application Publication No. 2008-001728. That is, 60 mL of a slurry of 0.5 to 1% by mass is prepared using a precisely weighed dry cellulose sample, and the pH is set to about 2.5 with a 0.1 mol/L aqueous hydrochloric acid solution. Then, 0.05 mol/L sodium hydroxide aqueous solution was added dropwise to measure the electrical conductivity. The measurement is continued until the pH is about 11. From the amount of sodium hydroxide consumed (V) until the change in electrical conductivity indicates the neutralization stage of the weak acid, the amount of acidic acid X1 is calculated using the equation below.

X1(mmol/g)=V(mL)×0.05/mass of cellulose (g)

The amount of acid groups in the cellulose fibers is preferably 0.2 to 2.2 mmol/g. If the amount of acidic groups is less than 0.2 mmol/g, the amount of metal ions present on the surface of the cellulose fiber is insufficient and the deodorizing function may be poor. If the amount of acidic air exceeds 2.2 mmol/g, the water repellency of the sanitary foil paper during papermaking deteriorates, and the deodorization load may increase.

Subsequently, an aqueous solution containing the metal compound is brought into contact with the oxidized cellulose fiber, so that metal ions derived from the metal compound form an ionic bond with a carboxylate group. In addition, it is considered that the carboxyl group is ionized and ionically bonded to the metal ion via the carboxylate group, or coordinated with the metal ion as described above.

The metal compound aqueous solution is an aqueous solution of a metal salt. Examples of the metal salt include a complex (a complex ion), a halide, a nitric acid salt, a sulfate salt, and an acetic acid salt, It is preferable that the metal salt is water-soluble.

Regarding the contact method of the metal compound, a dispersion of cellulose fibers prepared in advance and an aqueous metal compound solution may be mixed, and a dispersion containing cellulose fibers is applied on a substrate to form a film, and an aqueous metal compound solution is added to the film. You may impregnate it. At this time, the film may be fixed on the substrate or may be peeled off from the substrate.

Although the concentration of the aqueous metal compound solution is not particularly limited, 0.2 to 2.2 mmol are preferable and 0.4 to 1.8 mmol are more preferable with respect to 1 g of cellulose fibers.

The time for contacting the metal compound may be appropriately adjusted. The temperature at the time of contact is not particularly limited, but is preferably 20 to 40°C. In addition, the pH of the liquid at the time of contact is not particularly limited, but when the pH is low, since metal ions are difficult to bind to the carboxyl group, 7 to 13 are preferred, and pH 8 to 12 is particularly preferred.

That the oxidized cellulose fiber contains (arranged) metal ions can be confirmed by a scanning electron microscope image and an ICP emission analysis of the extract with a strong acid. That is, the presence of metal ions cannot be confirmed on a scanning electron microscope, whereas ICP emission analysis confirms that they contain metal. On the other hand, for example, when the metal is reduced by ions and exists as metal particles, the metal particles can be confirmed on a scanning electron microscope, and the presence or absence of metal ions can be determined. In addition, the presence or absence of metal ions can be determined also by a scanning electron microscope image and element mapping. That is, although metal ions cannot be identified by scanning electron microscopic images, it can be confirmed that metal ions exist by performing elemental mapping.

The antibacterial function is imparted by using one or more ions selected from the group of Ag and Cu as metal ions. On the other hand, the metal particles do not need to be bound to all of the acid groups of the cellulose fibers, and the residual acid groups can neutralize ammonia, which is an odor component, so that the deodorizing function is exhibited.

Sanitary tissue paper is made by papermaking raw materials including cellulose fibers. As a raw material for papermaking other than the cellulose fibers, for example, virgin pulp such as softwood pulp (NBKP) or hardwood pulp (LBKP), or waste paper pulp recycled from waste paper can be used. These pulp is suitably blended in a predetermined type and blending ratio suitable for the required quality of the sanitary paper. For papermaking raw materials, various chemicals can be added (internal additives) to stabilize the required quality and operation, and these chemicals include softening agents, bulky agents, dyes, dispersants, moisturizing agents, and drying agents. Examples include anti-freeze agents, water improvers, pitch control agents, and yield improvers.

The content ratio of the metal ion-containing cellulose fiber in the sanitary foil is preferably 3 to 30 wt%, and more preferably 5 to 15 wt%.

When the content ratio of the metal ion-containing cellulose fiber is less than 3 wt%, the amount of metal particles present on the surface of the cellulose fiber is insufficient and the deodorizing function may be poor. Although the sanitary foil paper may consist of only the cellulose fibers containing metal ions, there are cases where the dehydration load during papermaking may increase.

The basis weight of the obtained sanitary foil paper can be, for example, 7 to 40 g/m2, and the GMT value {(DMD×DCD) ^1/2 } can be 60 to 420 (N/m) as the strength of the sanitary foil paper. .

DMD and DCD are tensile strengths in the MD direction and the CD direction at the time of drying of the sanitary foil paper, respectively, and are measured according to JIS P8113. However, the width of the sample at the time of measurement is 25mm, and the unit of DMD and DCD is “N/m”.

The sanitary paper according to the embodiment of the present invention can be produced by a known papermaking method. First, a papermaking raw material obtained by properly mixing metal ion-containing cellulose fibers (or oxidized cellulose fibers before containing metal ions) and pulp is supplied from a raw material tank, and then diluted with white water to prepare a paper material. . This paper material is sent to the stock inlet by a fan pump after degassing screening and damping. The stock inlet feeds a paper material with fibers well-dispersed over the wire at an appropriate concentration, speed, and angle so that there are no blocks (small lumps) evenly across the entire width of the wire of the paper machine and no flowing streaks occur. As the stock inlet, there are a head box, a pressurized type, a hydraulic type, etc. that are installed at a high place to open the atmosphere, but any of them may be employed. Then, a sheet (web, wetland) is formed on the felt by jet-discharging the paper material between the wire and the felt in the stock inlet.

The web formed between the wire and the felt is closely transferred to the Yankee dryer with a pressure roll. The web is then dried by a Yankee dryer and a Yankee dryer hood, and while being creped by a creping doctor, the web is removed from the Yankee dryer and wound onto the reel through the reel drum. Yankee dryer is a drum made of cast iron or cast steel for drying the web, and the outer diameter is generally 2.4 to 6 m.

Here, creping is a method of mechanically compressing paper in the longitudinal direction (machine running direction) to form wavy wrinkles called crepe, and it is a method of forming a corrugated shape called crepe. It gives smoothness and aesthetics (the shape of the crepe). Then, a crepe is formed with a creping doctor by the difference in speed between the Yankee dryer and the reel (reel speed ≤ the speed of the Yankee dryer). The characteristics of the crepe also depend on the above speed difference, but if the basis weight of the base paper on the Yankee dryer is 7-40 g/m2, the basis weight on the reel becomes approximately 9-50 g/m2 and becomes larger than the basis weight on the Yankee dryer.

The crepe rate based on the difference in speed between Yankee dryer and reel is defined by the following equation.

Crepe rate (%) = 100 × (Yankee dryer speed (m/min)-reel speed (m/min) ÷ reel speed (m/min))

The quality of the crepe and the operability of the crepe are almost determined by the crepe rate, and the crepe rate in the present invention is most suitable in the range of 10 to 50%.

Next, an absorbent article according to an embodiment of the present invention will be described.

1 is an external view of an absorbent article (pants-type paper diaper) 200 according to a first embodiment of the present invention. The absorbent article 200 includes an absorbent article body portion 20 having an absorbent property, and an exterior body 100 that forms a pants shape by holding the absorbent article body portion 20 inside.

For the exterior body 100, a nonwoven fabric made of a thermoplastic resin such as polypropylene, polyester, or polyethylene and manufactured by a spunbond and air-through manufacturing method may be used. In addition, the exterior body 100 is preferably formed by laminating at least two or more sheets having an exterior sheet and an interior sheet.

The absorbent article body portion 20 is elongated and elongated, and is disposed between the two legs of the absorbent article 200 because its width is slightly narrowed near the center portion in the longitudinal direction.

FIG. 2 is a cross-sectional view of the absorbent article main body 20 taken along line A-A in FIG. 1. The absorbent article main body 20 includes a liquid-permeable hydrophilic surface sheet (top sheet, outer layer sheet) 2 forming a body-contact side surface (top surface in FIG. 2), a liquid impermeable back sheet 6, and It comprises absorbent cores 4a and 4b which are disposed between the hydrophilic top sheet 2 and the back sheet 6 and have a super absorbent polymer and an adhesive. Further, each of the absorbent cores 4a and 4b is covered with core wrap sheets 10a and 10b, respectively. In addition, both sides of the absorbent article main body 20 stand up as a three-dimensional gather 30 composed of a water-repellent side sheet to prevent urine and the like from leaking to the side.

In addition, in this embodiment, the absorbent cores 4a and 4b covered with the core wrap sheets 10a and 10b, respectively, are stacked so that the absorbent core 4a faces the hydrophilic surface sheet 2 side, so that the absorbent core ( The width of the absorbent core 4b is approximately 1/2 compared to the width of 4a).

For one absorbent article main body 20, the absorbent core and the core wrap sheet surrounding the absorbent core may be one or plural.

The hydrophilic surface sheet 2 is made of a non-woven fabric, and since it contacts the skin of the wearer, it may be formed of a material that is soft in the touch and does not irritate the skin. As the hydrophilic surface sheet 2, an air-through nonwoven fabric, a point bond nonwoven fabric, a spunbond nonwoven fabric, a spunless nonwoven fabric for synthetic fibers such as polypropylene, polyethylene, and polyester is used. In particular, an air-through nonwoven fabric with a small amount of liquid return is most suitable.

The back sheet 6 may be formed of a liquid impermeable material having a waterproof property that does not leak into the underwear, such as liquid held in the absorbent article body 20, and a thin plastic film such as a breathable polyethylene film. can do. In addition, by using a moisture-permeable film as the back sheet 6, it is possible to reduce moisture or stuffiness.

The absorbent cores 4a and 4b can be formed by mixing particles of a hydrophilic fiber (flap) such as wood flap pulp and a highly absorbent resin (SAP). In addition, a so-called SAP sheet in which SAP is used as a sheet may be used. As the hydrophilic fiber, instead of the wood pulp flap, synthetic fibers, polymer fibers, or the like may be used. In addition, antibacterial fibers may be blended as hydrophilic fibers.

Next, the core wrap sheets 10a and 10b will be described. In the absorbent article according to the embodiment of the present invention, it has an excellent deodorizing function by using the sanitary paper of the present invention described above for the core wrap sheets 10a and 10b. Further, since the core wrap sheets 10a and 10b have sufficient strength, it is possible to obtain an absorbent article in which agglomeration or tearing of the core wrap sheet is difficult to occur.

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

The absorbent article is not limited to the pant-type paper diaper, but may be of a type that is in the form of elongated pieces like a sanitary napkin and is in contact with a local area. Further, in the above embodiment, the liquid-permeable outer layer sheet 2 covers only one side (body-contact side surface) of the absorbent core 4a, but covers both sides of the absorbent core with a liquid-permeable outer layer sheet, You may make it possible to absorb urine or the like from both sides of the back side.

In addition, the core wrap sheet is not limited to covering the absorbent core, and may be used after being laminated on the surface of the absorbent core. Further, when multiple absorbent cores are laminated, a core wrap sheet may be sandwiched between each absorbent core.

In addition, the absorbent article according to the embodiment of the present invention can also be applied to a pet sheet (pet sheet).

[Example]

Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is of course not limited to these examples.

<Experiment A: Preparation of cellulose fibers containing metal ions>

Softwood bleached kraft pulp was used as the raw material pulp, and 2 g of sodium hypochlorite as a co-oxidizing agent was added to 0.2 g of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO), and 2 g at room temperature. An oxidation reaction was performed while stirring for a period of time to obtain a dispersion of oxidized cellulose fibers (TEMPO oxidized cellulose fibers). This TEMPO oxidized cellulose fiber has a carboxyl group or carboxylate group on its surface. Table 1 shows the amount of acid groups (per 1 g of oxidized cellulose fibers) of TEMPO oxidized cellulose fibers before containing metal ions.

To the TEMPO oxidized cellulose fiber obtained by the above operation, a metal salt (CuCl ₂ ) aqueous solution having the pH and concentration (per 1 g of oxidized cellulose fiber) shown in Table 1 was added and stirred. Accordingly, Cu ions were contained in the oxidized cellulose fibers and washed to remove unreacted metal salts. Table 1 shows the content of metal ions in the oxidized cellulose fibers. In addition, Example 9, AgNO ₃ as a metal salt solution An aqueous solution was used to contain Ag instead of Cu ions.

In this way, it was confirmed in Examples 1 to 9 that metal ion-containing cellulose fibers could be produced.

<Experiment B: Preparation of sanitary foil paper and core wrap sheet>

Next, the metal ion-containing cellulose fiber of Example 1 and the pulp (NBKP and LBKP) were blended at the mixing ratio shown in Table 2 to prepare a pulp slurry, followed by papermaking, and the sanitary foil paper of Examples B1 to B4 (tissue paper, toilet paper) , Paper towel) and the core wrap sheets of Examples B1 to B6 were prepared. In addition, the sanitary foil paper and the core wrap sheet of Examples B1 to B4 have the same composition.

As Comparative Example 1, the sanitary thin paper sheet of Example B1 (which contained Cu ions in cellulose oxide fibers) was further impregnated with a reducing agent solution of 200 ppm, and the excess aqueous solution was removed by overlapping the filter paper, and a blow dryer at 50°C. By drying for 15 minutes, Cu ions in the sanitary foil sheet were reduced to form Cu particles to prepare toilet paper and core wrap sheets.

As Comparative Example 2, commercially available metal (Cu and Ag)-containing metal-supported zeolite high-density crystallized pulp (trade name Celgaia (registered trademark)) was blended in the ratio of Table 2 with respect to NBKP, followed by papermaking to prepare toilet paper and core wrap sheet. did.

In addition, when the sanitary foil paper and core wrap sheet of Examples B1 to B6 were observed with a scanning electron microscope, only the fibers of the paper were identified. On the other hand, in Comparative Example 1, it was confirmed that metal particles were supported between the fibers of the paper.

In addition, the sanitary foil paper and core wrap sheet of Examples B1 to B6 and Comparative Example 1 were dissolved in a strong acid and then analyzed for ICP (high frequency inductively coupled plasma) emission of the extract, indicating that all metals were contained. Confirmed. From the above, the sanitary foil paper and core wrap sheet of Examples B1 to B6 contain metal ions in the oxidized cellulose fiber, while the sanitary foil paper and core wrap sheet of Comparative Example 1 contain metal ions contained in cellulose oxide. Was reduced to.

The following evaluation was performed about the obtained sanitary foil paper and core wrap sheet.

<Basic weight>

The basis weight of the obtained sanitary foil paper and core wrap sheet was measured according to JIS P 8124.

<Paper thickness>

The paper thickness (mm/10 sheets) when the obtained sanitary foil paper and the core wrap sheet were stacked 10 plies (sheets) was measured with a PEACOCK type thickness meter (brand name). The measurement pressure was set to 3.7 kPa.

<Tensile strength>

The tensile strength of the obtained sanitary foil paper and core wrap sheet in the MD direction and the CD direction at the time of drying was measured according to JIS P8113. The sample width was 25 mm. Further, the tensile strength in the MD direction and the CD direction during drying are indicated by DMD and DCD, respectively.

Moreover, the tensile strength (WMN) in the MD direction at the time of wet of the obtained sanitary foil paper and the core wrap sheet was measured according to JIS P8135. The sample width was 25 mm. In the case of toilet paper, four samples were stacked and measured.

<absorption rate>

It measured according to JIS S3104 6.5 (old JIS).

First, a pipette adjusted so that the dropping amount of one drop was 0.1 ml was prepared. The test piece was fixed to a holding frame, and 0.1 ml of distilled water at a temperature of 20±1° C. was added dropwise at a height of 10 mm above the test piece. After the water droplets reached the test piece, the time until the mirror reflection of water completely disappeared was measured in 0.1 second increments with a stopwatch. The test was performed 5 times and the average value was evaluated as the absorption rate (seconds).

<Lint (Fine powder such as paper dust)>

According to JIS B9923 (tumbling method), the dusting test of the sanitary foil paper and core wrap sheet was performed, and it measured with a particle counter (Lion product, product name "KC-01D1"). It evaluated based on the following criteria. The better the evaluation, the less dropping of fine powder such as paper powder or zeolite.

◎: Very good

○: Normal

×: Bad

<Deodorant effect>

A saturated gas of an aqueous ammonia solution (2 mL of ammonia: 2 mL of water) was inserted into a gas bag with cock containing four 5 cm x 5 cm test pieces, and 1.5 L of air was further filled with an air pump. The saturated gas was collected in the gas phase of a sealed container containing an aqueous ammonia solution. The concentration of ammonia gas in the gas bag after filling saturated gas and air was 80 to 90 ppm. Next, the suction tube and the rubber tube were connected to the detection tube, and the rubber tube was connected to the gas bag. Then, after 50 minutes elapsed after filling air, the concentration of ammonia gas in the gas bag was measured.

◎: Very good residual concentration is less than 1/4 of the initial

○: Normal residual concentration is less than 1/3 of the initial stage, more than 1/4

×: Poor residual concentration is more than 1/3 of the initial

The obtained results are shown in Table 1, Table 2, and Table 3. In addition, Table 2 shows the results of the sanitary foil paper (tissue paper, toilet paper, paper towel), and Table 3 shows the results of the core wrap sheet.

[Table 1]

[Table 2]

[Table 3]

As shown in Tables 2 and 3, in the case of each example, there was little drop of fine powder such as paper powder, and it had an excellent deodorizing function. In particular, in the case of Examples B5 and B6 in which the content ratio of the metal ion-containing cellulose fiber in the sanitary foil is 5 to 15 wt%, the evaluation of the dropping of paper powder and the deodorizing function is more excellent compared to the other examples.

On the other hand, in the case of Comparative Example 1 in which Cu ions in the oxidized cellulose fibers were reduced to Cu particles, the deodorizing function was slightly lower than in each example.

In the case of Comparative Example 2 made by doubling the metal-supported zeolite high-density crystallized pulp (trade name Celgaia (registered trademark)), the drop of fine powder such as paper powder was remarkable.

<Experiment C: Tensile strength and breaking length of core wrap sheet>

A pulp slurry using NBKP, which is a general pulp (cellulose fiber), the cellulose fiber containing Cu ion of Example 1, and the metal-supported zeolite high-density crystallized pulp (trade name Celgaia (registered trademark)), respectively, was prepared in a prismatic form. Sheets 1 to 3 having a basis weight of 18±0.5 g/m2 were prepared by papermaking with a (手抄械). In addition, no intellectual strength enhancing agent was added.

Sheets 1 and 2 were each made of 100% NBKP and Cu ion-containing cellulose fibers. Moreover, the sheet|seat 3 made the compounding ratio of the metal-supported zeolite high-density crystallization pulp (trade name Celgaia (registered trademark)) and pulp (NBKP) the same as in Comparative Example 2, and was made into papermaking.

For each obtained sheet, the basis weight, paper thickness, and tensile strength were measured in the same manner as in Experiment B. The density was calculated from the basis weight and the paper thickness, and the fracture length was calculated from the basis weight and tensile strength. In addition, the tensile strength was measured with a sample width of 25 mm, and the breaking length was determined from the following equation. In addition, since the strength of the sheet 1 was low, three sheets were stacked to measure the tensile strength, divided by 3, and converted into tensile strength per sheet. Table 4 shows the obtained results.

Breaking length (km) = Tensile strength (kgf) × 1000/{Weighing (g/㎡) × Sample width (mm)}

[Table 4]

As apparent from Table 4, the strength of the sheet 2 is higher than that of the sheet 1. This is thought to be due to an action such as beating treatment in the manufacturing process of cellulose fibers containing metal ions. Therefore, the strength of Examples B1 to B4 in which the papermaking raw materials obtained by mixing ordinary pulp (such as NBKP) and cellulose fibers containing metal ions are formed is the same strength as in the case of papermaking.

On the other hand, in the case of the sheet 3 containing 10 wt% of zeolite-supported cellulose fibers, the strength was reduced by about 20% compared to the sheet 1. It can be considered that this is because zeolite is crystallized in the cellulose fiber, which causes the fiber to expand, inhibiting the flattening of the cellulose fiber, and reducing hydrogen bonds between the fibers. It is also considered because the zeolite-supported cellulose fibers contain a large amount of short fiber content.

2; Outer layer sheet (hydrophilic surface sheet)
4a, 4b; Absorbent core
20; Absorbent article body part
10a, 10b; Core wrap sheet
200; Absorbent article

Claims (2)

For oxidized cellulose fibers having a carboxyl group or carboxylate group on the surface and selectively oxidized with a primary hydroxyl group at the C6 position, Ag, Au, Pt, Pd, Ni, Mn, Fe, Ti, Al, Zn and Cu groups (群) comprises an oxidized cellulose fiber in which ions of one or more metal elements selected from are ionically bonded to the carboxyl group or carboxylate group,
The content of the metal ions in the oxidized cellulose fiber is 10 ~ 60mg / g,
Sanitary foil paper in which the content of the cellulose fibers containing metal ions is 5 to 15 wt%.
An absorbent article comprising an absorbent core, a core wrap sheet covering or laminated on the absorbent core, and a liquid-permeable outer layer sheet covering at least one side of the core wrap sheet,
The said core wrap sheet is an absorbent article which is the sanitary foil paper of Claim 1.

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