JPH03268752A - Absorptive article - Google Patents

Abstract

PURPOSE:To provide a high rate of diffusing and absorbing body fluid and excellent disaggregation in water by using a sheet-like body consisting of carboxymethylcellulose or carboxyethylcellulose, a water-insoluble or hardly water-soluble inorg. powder and water dispersible fibers in a part of an absorber. CONSTITUTION:A least a part of the absorber is the sheet-like body consisting of the carboxymethylcellulose(CMC) or carboxyethylcellulose(CEC), the water- insoluble or hardly water-soluble inorg. powder and the water dispersible fibers and is produced by an ordinary paper making method. The CMC or CEC having the degree of the substitution within a 0.1 to 1.5 range is preferable. Zeolite, kaolin, etc., are used as the water-insoluble or hardly water-soluble inorg. powder and the grain size thereof is preferably <=30. The water dispersible fibers may be fiber blank materials, such as wood pulp fibers and rayon fibers, having dispersion performance in water and the fiber length thereof is preferably about <=40mm. The sheet-like body having the above-mentioned constitution exhibits the excellent property to diffuse and absorb the bodily fluid and the excellent disaggregation in water as well as the result of comparison tests.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to an absorbent article using an ice-melting absorbent material.

(Prior art and its problems) Absorbent articles such as sanitary napkins and disposable diapers are equipped with an absorbent material that quickly absorbs body fluids such as menstrual blood and urine drained from the human body. Body fluids do not leak,
Moreover, the structure is such that body fluids do not wet the human body.

The absorbent material currently in common use is a sheet-like material consisting of a mixture of flocculent pulp and water-absorbing polymer particles. This material is highly flexible and elastic, and at the same time
Although it has excellent liquid absorption ability, the liquid diffusion and absorption rate at which the absorbed liquid is diffused and absorbed in all four directions within the sheet is low.
The drawback is that the amount of liquid absorbed in a short period of time is low. Therefore, in absorbent articles using this material as an absorbent body, leakage of body fluids may occur due to the low rate of liquid diffusion and absorption. Furthermore, this absorbent body also has the disadvantage that the water-absorbing polymer particles tend to fall off during handling or use.

On the other hand, absorbent products such as sanitary napkins and disposable diapers are required to have the property of disintegrating and dispersing finely in water, that is, to have ice-melting properties, so that they can be disposed of after use by flushing toilets. . From this point of view, those containing water-absorbing polymer particles have poor ice-melting properties;
It's inappropriate.

(Problem of the Invention) An object of the present invention is to provide an absorbent article using an absorbent body that has excellent diffusion and absorption rate of body fluids and excellent ice-melting properties.

(11! Means for Solving the Problem) The present inventors have conducted extensive research to solve the above problem, and as a result, have completed the present invention.

That is, according to the present invention, an absorbent characterized in that a sheet-like body made of carboxymethyl cellulose or carboxyethyl cellulose, a water-insoluble or slightly water-soluble inorganic powder, and a water-dispersible fiber is used for at least a part of the absorbent body. Sexual goods are provided.

The absorbent used in the present invention contains at least a portion of carboxymethyl cellulose (hereinafter also abbreviated as CMC) or carboxyethyl cellulose (hereinafter also abbreviated as CEC), a water-insoluble or poorly water-soluble inorganic powder, and a water-dispersible It is a sheet-like body made of fibers and can be easily manufactured using normal papermaking methods.

The CMC or CEC has a structure in which a part of the hydroxyl groups of cellulose is substituted with a carboxymethyl group or a carboxyethyl group, and the degree of substitution (hereinafter abbreviated as DS, indicating the degree of substitution per glucose unit) is 0.1
It is preferable to specify the range of 1.5 to 1.5.

When O8 is less than 0.1, the resulting sheet does not exhibit adequate absorbency and ice-melting properties. On the other hand, even if the DS exceeds 1.5, the performance does not improve even though the manufacturing cost is high due to the high DS. The preferred DS is in the range of 0.2 to 1.0.

CMC or CEC may be in the form of a free acid, including water-insoluble or water-soluble salts, such as aluminum salts, barium salts, zinc salts, tin salts, manganese salts.

It may be in the form of a calcium salt or the like. CMC and CEC
are used alone or in combination of two or more. Among these, acid type and calcium salt type, or mixed salt type containing calcium salt are preferred.

As the water-insoluble or slightly water-soluble inorganic powder, nonmetallic inorganic substances, metals, water content (It) soluble salts, etc. are used. Specific examples of these include aluminum oxide lz.

Metal oxides such as titanium oxide; carbides such as silicon carbide and boron carbide; nitrides such as trisilicon tetranitride and boron nitride; metal hydroxides such as aluminum hydroxide and magnesium hydroxide; mica, feldspar group, and silica minerals Silicate minerals such as synthetic zeolite and natural zeolite; Titanate compounds such as potassium titanate and barium titanate; Carbonate compounds such as calcium carbonate, barium carbonate, magnesium carbonate, and zinc carbonate; Barium sulfate; Examples include sulfate compounds such as calcium sulfate and strontium sulfate; silicate compounds such as zinc silicate, magnesium silicate, and barium silicate; phosphate compounds such as zinc phosphate;
They may be used alone or in combination of two or more.

Among the above inorganic powders, zeolite,
These are kaolin, talc, and calcium carbonate. As the zeolite, A type, X type, Y type, etc. are used.

The particle size of the water-insoluble or poorly water-soluble inorganic powder is preferably 30 or less, more preferably in the range of 0.01 to 10 iJa. If the particle size is too large, the dispersibility with CMC or CEC will not be sufficient, and if the particle size is too small, the retention of inorganic powder will be insufficient and the freeness during papermaking will be poor. It is not possible to make paper with a large number of sheets.

The water-dispersible fibers are not particularly limited, and may be any fiber material that essentially has water-dispersibility. Specifically, wood pulp fibers, non-wood plant fibers, rayon fibers, etc. can be mentioned.

In the present invention, for example, graph 1 pulp or sulfide pulp for paper making, dissolving valve for synthetic fibers, etc. are suitably used, but vegetable fibers such as straw pulp, hemp pulp, cotton pulp, etc., polyamide, polyester, etc. Synthetic fibers, and even S-quality fibers such as glass RIIA, asbestos, rock wool, slag wool, silica wool, silica-alumina wool, etc., can also be used.

The fiber length of the water-dispersible fibers is generally about 30+a or less, preferably about 30+a+m or less, and a fiber length of 20 mm or less is particularly optimal. If a considerable amount of fibers with a length longer than about 40 mm are present in a sheet-like material, the fibers will disperse in water and fall apart, but depending on the length, there is a tendency for the fibers to form "nooses". , worsening liquidity. On the other hand, if the fiber length is shorter than 1 inch, the effect of improving the wet strength of the obtained sheet material will be reduced.

The inorganic powder includes (a) inorganic powder and (b) CMC or CEC.
The weight ratio (a)/(b) is preferably (a)/(b)
)=90/10-5/95, more preferably 60/40
~10/90, more preferably 40/60~15/8
The paper is mixed so that it becomes 5. When this ratio exceeds 90/10 and the amount of inorganic powder increases, it becomes difficult to make paper, and the strength becomes weak, making it difficult to use as a sheet. on the other hand,
If the above weight ratio is less than 5,795, the effect of adding the inorganic powder will not be sufficiently exhibited, it will be difficult to separate it from the wire during paper making, and the resulting sheet will become somewhat hard.

The amount of water-dispersible fiber mixed is (a) inorganic powder and (b) CM
It is preferable that the total amount of C or CEC is 50% by weight or less. This is because if the weight exceeds 50%, the fibers tend to bind together in water. On the other hand, if the amount of fiber used is too small, a sufficient effect of improving wet strength cannot be obtained. Therefore, water-dispersible fibers consist of (a) inorganic powder and (b) c
5 to 5 per 100 parts by weight of the mixture with Mc or CEC
It is preferable to add 0 parts by weight, especially 20 parts by weight or less.

In order to preferably produce the sheet material of the present invention, water-insoluble fibrous CMC or CEC1 inorganic powder, fibers, and if necessary, other additives such as a coagulant are dispersed in water, and papermaking raw materials are prepared. Prepare. Next, this papermaking raw material (paper stock) is supplied to a wire bat (Fourdrinier section 2 circular mesh section) of a paper machine such as a Fourdrinier paper machine or a cylinder paper machine to form a wet paper. This wet paper is then transferred to a press part (squeezing part) and a dry part (drying part), where it is dehydrated and dried to form a sheet-like body.

However, if the wet paper paper is directly formed into a sheet, the resulting sheet will not exhibit sufficient absorbency and ice-melting properties. Therefore, an alkaline agent is added to the wet paper at an appropriate stage by spraying, coating, etc. to make it ice-melting.

Examples of alkaline agents include hydroxides such as sodium hydroxide and potassium hydroxide, carbonates such as sodium carbonate and potassium carbonate, borates such as borax, phosphates such as sodium monophosphate, and sodium silicate 13. silicates and mixtures thereof, etc. are used.

These alkaline agents are preferably added in the form of an aqueous solution containing an organic solvent such as methanol or acetone in order to prevent damage to the wet paper. May be added. By drying after alkali treatment, a sheet-like material exhibiting ice-melting properties can be obtained. After drying the wet paper, the pH of the paper is 7~】2,
It is desirable to adjust the angle preferably within the range of 7.5-9°5.

When the wet paper is mainly composed of CMC or CEC in a free acid state, the coarse CMC or CEC is converted into an alkali salt. In addition, if the wet paper is mainly composed of metal salts such as aluminum salts of CMC or CEC, the alkaline agent will adhere to the surface and between the fibers.7 Due to the action of such an alkaline agent, the sheet will have ice-melting properties. A solid body is obtained.

The absorbent article of the present invention uses a sheet-like body as described above for at least a part of the absorbent component, and has a liquid-permeable sheet such as a nonwoven fabric and a skin-resistant sheet on the body and contact surface of the absorbent body. It has a configuration in which a leak-proof film or the like is arranged on the contact surface side, and includes napkins, disposable diapers, and the like.

Other absorbents may be used in combination with the sheet-like material used in the present invention, and examples of such absorbers include flap pulp, polymer absorbers, absorbent paper, and the like.

Next, one embodiment of the absorbent article of the present invention will be described with reference to the drawings. FIG. 1 shows a cross-sectional diagram of a sanitary napkin, in which 1 is an ice-dissolving nonwoven fabric, 2 is a pulp layer, 3 is absorbent paper, 4 is an ice-dissolving sheet according to the present invention, and 5 is a water-soluble leak-proofing material. are shown in each case.

As the ice-melting nonwoven fabric 1, a conventionally known one is used. Examples of such products include those using, as a binder, a copolymer of an unsaturated carboxylic acid (2 to 60 molar pairs thereof are neutralized salts) and an unsaturated carboxylic ester (JP-A-1-306661). ), those using carrageenan or galactomannan (Japanese Patent Application Laid-Open No. 61-296159),
Those using alkali cellulose ether sulfate resin (JP-A-50-52371), those using sulfated cellulose ester alkali metal salt (JP-A-50-1
4.2562), etc.

As the pulp layer 2, one formed from a normal bulb obtained from wood such as softwood or hardwood is used.

As the absorbent paper 3, for example, thin paper or the like is used.

As the ice-melting absorbent sheet 4, the above-mentioned CMC of the present invention is used.
and CEC1 water-insoluble or slightly water-soluble inorganic powder and water-dispersible Jil#1. A sheet-like body consisting of is used.

As the water-soluble leakage preventive material 5, for example, a film formed from a water-soluble resin such as polyvinyl alcohol or carboxylated acrylic acid polymer is used.

(Effect of the invention) C used as an absorbent component in the absorbent article of the present invention
A sheet-like body made of MC or CEC, a water-insoluble or water-releasable inorganic powder, and water-dispersible fibers exhibits excellent diffusion and absorption properties for body fluids. Therefore, the absorbent article of the present invention exhibits effects such as increasing the liquid absorption rate, increasing the amount of liquid absorbed in a short period of time, and preventing liquid leakage from the absorbent body. Further, the absorbent article of the present invention includes:
Since the sheet material used as the absorbent component has excellent ice-melting properties, it has the advantage that it can be thrown into a flush toilet and disposed of after use.

(Example) Next, the present invention will be explained in more detail with reference to embodiments.

Example 1 60 parts by weight of fibrous CMC (degree of etherification DS=0.65, free acid state, manufactured by Nichirin Chemical), zeolite (type A, Na, 0.2Si02.AQ, 03.4.511.O
2 Average particle size 5, Mizusawa Chemical) 40 parts by weight and fiber length 3
A handsheet with a basis weight of 80 B7 m was prepared from a mixed raw material consisting of 20 parts by weight of ~20 m1 of NBKP pulp.

Next, the obtained sheet 1 was dried into a sheet by roll drying at 120°C, impregnated with a 50% methyl alcohol solution containing 3 weight 2 of sodium hydroxide, and then heated at 110°C. After drying, a sheet 1 of sample &1 shown in Table 1 was prepared.

Hereinafter, the sheet-like bodies were changed as shown in Table 1 and samples Nc1~
A sheet-like body of Na5 was obtained.

The inorganic powders shown in the table are as follows.

Tar: MgO・Sin, Nippon Mistron bentonite: Bentonite Tone, Kanto Bentonite Mining activated white soil: Galleon Earth, Mizusawa Chemical Co., Ltd. Ori:, /: Hl-vHITE, evaluation items for samples made by Nissei Kyoiku Co., Ltd. are liquid absorption capacity and ice melting ability, and the test methods are shown below. In addition, as comparative products, acrylic acid polymer sodium salt powder, fluff pulp, and absorbent paper, which are highly absorbent polymers, were evaluated in the same manner. The evaluation results are shown in Table-1.

(1) Absorption capacity: T-bag method absorption capacity is the amount by which a sheet-like material can retain liquid without dissolving or dispersing in water.

0.3 g of sample in a non-woven tea bag (6 x 8 cm)
Precisely weigh, seal, and leave it horizontally for a certain period of time (0, 5, ■, 2.5
After soaking (for 1 minute), drain for 1 minute on a 30 degree inclined wire mesh,
The weight (a) g was measured, and the same measurement was performed on the tea bag without the sample to determine the weight (b) g, and the water absorption amount was calculated using the following formula to determine the liquid absorption magnification.
) Cut the ice-melting sheet into 2x2c+o, put it in a water tank containing water IQ at 10℃, let it stand for 1 minute, and then gently stir it to melt or dissolve the ice. It was evaluated as follows.

○: Good ice-melting property △: Slightly poor ice-melting property ×: Poor ice-melting property Table-1 1... Ice-melting nonwoven fabric 2... Pulp layer 3... Absorbent paper 4... Ice-melting sheet material 5... Water-disintegrable leak-proofing material Next, an absorbent article was made by using the NQI sheet of the present invention and layering an ice-dissolving nonwoven fabric on the skin-contacting side and a polyvinyl alcohol film on the non-skin-contacting side. It was confirmed that this material has a high absorption capacity and that it decomposes and disperses even when dumped into running water such as in a flush toilet.

[Brief explanation of drawings]

FIG. 1 shows a cross-sectional configuration diagram of one embodiment of the absorbent article of the present invention.

Claims (1)

[Claims] (1) carboxymethyl cellulose or carboxyethyl cellulose, and a water-insoluble or poorly water-soluble inorganic powder,
An absorbent article characterized in that a sheet-like body made of water-dispersible fibers is used for at least a portion of an absorbent body.