JPS607052Y2 - sanitary napkins - Google Patents

Description

[Detailed description of the invention] The present invention is a sanitary napkin ( pad).

The product of this invention can be said to have the properties of both a tampon and a napkin.

Conventional sanitary napkins are formed from three layers.

That is, the top sheet covers the surface, the water-absorbing material filled inside, and the waterproofing material to prevent moisture from leaking downward and laterally.

Of the ingredients that make up these sanitary napkins, 9 of the total weight
Around 0% is occupied by water-absorbing and blood-absorbing materials.

The main components of this water-absorbing and blood-absorbing material are cotton-like pulp made from wood pulp and what is called paper cotton, which is processed into crepe paper and laminated.

Conventional sanitary napkins having such a structure have the following drawbacks, which are mainly caused by the water-absorbing material.

1. It is inconvenient to carry because it is bulky, and it is noticeable and bothersome when in use.

2. The amount of water and blood sucked is insufficient in proportion to the volume, and overflow is likely to occur.

3. As water absorption and blood absorption progresses, the entire body becomes deflated and sagging, and a feeling of flatness occurs.

4. It tends to shift when loaded, so it needs to be fixed to the menstrual belt with adhesive tape, etc.

As a result of intensive study to drastically improve these shortcomings,
By incorporating a compressed solid molded cellulose nonwoven fabric with high water absorption and recovery properties into the interior, we were able to achieve the following effects.

That is, a. By using a cellulose-based nonwoven fabric with high water absorption performance as a raw material for the compressed solid molded product, it becomes possible to significantly compact the napkin as a whole.

b The compressed solid molded product restores its shape by absorbing water and blood and expands in volume, so there is no feeling of stiffness or flatness.

By devising the shape of the C convex protrusion, it adheres to the local area,
Concerns about misalignment can be reduced.

As mentioned above, the basic idea of the present invention is to incorporate a compressed solid molded product as a component of a sanitary napkin and fully utilize the properties of the compressed solid molded product as a water-absorbing and blood-absorbing material.

Therefore, in explaining the present invention in more detail, first of all, the compressed solid molded product of the present invention and its properties will be explained.

The compressed solid molded product with good water absorption and restoring properties used in the present invention is a bulky cellulose nonwoven material with excellent water absorption and water retention properties, such as Japanese Patent Publications No. 49-6787, No. 49-38940, No. 49-38941, and Japanese Patent Application No. 1983 (No. 52). -23059 or Japanese Patent Publication No. 49-30665I- is compressed and solidified.
Manufacturing method for water-absorbing solid fabric material
3rd patent application) and “Production method of water-absorbing compression molded product” (
A method such as that disclosed in Patent application filed May 10, 1975) is used.

The above-described nonwoven fabric is easily molded by pressure compression, and has a high property of expanding and restoring its original shape by absorbing water.

The performance of this compressed body can be expressed by characteristics such as compression rate, expansion rate, volume recovery rate, and water retention rate recovery rate.

Compression rate is calculated from the change in specific gravity of the nonwoven fabric before and after pressurization, expansion rate is calculated from the specific gravity before and after water absorption, and volume recovery rate is calculated from the ratio of compression rate and expansion rate. Then, the water retention rate was calculated from the ratio of the water retention capacity of the original fabric before pressurization to the water retention capacity after water absorption.

Tables 1 and 2 compare these characteristic values for typical fabrics and nonwoven fabrics.

In the case of Table 2, the compression pressure is 1100ko/c7I! It is.

All fabrics other than towels are cellulose-based nonwoven fabrics, but for the purpose of this invention, the recovery rate of volume and water retention is 60%.
It is preferable to use a cellulose-based nonwoven fabric having a content of 80% or more.

These performances can be achieved by adding a starch/acrylonitrile graft copolymer (for example, GrainProce) to the nonwoven fabric.
The effect becomes even more pronounced when compressed solid molded products made from composites to which Polymer 35A (Sssing Co., Ltd.) or partially crosslinked carboxymethylated cotton linters (e.g., Aqualon, manufactured by Hercules) are attached are used. .

The general method for producing these compressed solid molded products is to insert the raw nonwoven fabric into a fixed mold, but continuous production is also possible by a method as shown in FIG.

That is, the required number of cellulose-based nonwoven fabric tapes 3 are taken out from the can 2 on the turntable 1, passed through the first focusing guide 4, and further focused by the second focusing guide 5, and the appropriate number of tapes 3 are taken out by the action of the turntable 1. After being twisted and passed through a guide 6, it is compressed and solidified with a compression roll 7, and then rolled up into a cheese shape with a winder 9 while being passed through a traverse guide 8.

The degree of heating can be adjusted by adjusting the circumferential speed of the compression roll and the rotational speed of the turntable.

A second important consideration is the shape of the compacted solid molded object.

This shape is determined by determining the shape when inserted in a dry state and the shape of expansion after water absorption and blood absorption.

First of all, various shapes can be considered for the insertion shape, such as the length and width of the napkin, as shown schematically in the plan view opening and cross-sectional view A in Figures 1, 2, and 3, but as much as possible, it can be inserted without causing discomfort to the private parts. It is necessary to select a shape that can be fitted by considering the contrasting layer of the product.

The expanded shape varies greatly depending on the above-mentioned insertion shape and the form of the raw nonwoven fabric used before compression.

Assuming that a cylindrical mold with a diameter of 1 cm and a height of 5 cm is selected as the fixed mold, the relationship between the shape of the original fabric and the state of expansion is illustrated as shown in FIGS. 4, 5, and 6.

In Figures 4 to 6, A is the original shape, B is the folded or focused (accumulated) shape, C is the shape placed in the mold, D is the shape after molding, and E is the shape after water absorption and expansion. It shows.

Note that Figure 4 shows a square sheet, Figure 5 shows a tape-shaped sheet that was heated and collected, and Figure 6 shows a collection of thin pieces that were formed.

The state of expansion varies widely depending on the shape of the original fabric used.

By devising the performance and insertion shape of the compression body in this way, it is possible to commercialize sanitary products that are extremely compact and suit the purpose.

The features of the present invention have been described above, and will be explained more specifically with reference to examples.

Example 1 Among the sheets having the characteristics shown in Table 1, 0 items were cut into 15cm x 15cm pieces and placed in a stainless steel capsule with a diameter of 1cm (inner diameter) and a height of 5cm as shown in Figure 4. and compressed under a pressure of 9 Icd at 1100 to obtain a solid material.

The properties of this solid are shown in the table.

This molded piece was assembled into the center of the napkin, the upper and lower sides were wrapped with cotton-like pulp, the lower surface was covered with waterproof paper, and the entire napkin was covered with a covering material.

A sanitary napkin with the structure shown in Figure 8 was made, and distilled water colored with Congolet was dripped at 10 cc for 73 minutes. After the dripping, the napkin was broken down into each component, and the water absorption weight was measured and compared. It is 3.

From Table 3 and Figure 8, most of the dropped water (85%) is
It can be seen that this compressed solid material absorbs water and exhibits a large expansion state.

Rayon dry non-woven fabric with towel binder Cellulose non-woven fabric (manufactured by Mitsubishi Rayon, TCP) Cellulose-based non-woven fabric with no holes on the surface of the non-woven fabric (manufactured by Mitsubishi Rayon, T
CP) There are holes on the surface of the nonwoven fabric D and Hercnles A
qnalon R deposited Note: Numbers in parentheses in the materials column refer to the numbers in FIG.

Example 2 The material D in Tables 1 and 2 was slit into tapes with a width of 10 m and 1 m, and while being sprinkled with Aqualon R, the five tapes were heated using a device as shown in Figure 7, and 500 kg/kg was slit with a compression roll. A compressed solid material was produced by winding it up with wine goo while applying a pressure of C1 ft.

After cutting this into 1.4 cm wide and 7 cm long, wrap the top and bottom with the above-mentioned cellulose nonwoven fabric (not compressed), place cotton pulp on top, and cover with waterproof paper. A napkin with a structure covered with wood (Fig. 9B
) was prepared.

Model blood with the following composition was prepared on this napkin, and this model blood was dropped onto the napkin at a rate of 10cc/3ml. After the dropping was completed, the napkin was broken down into each component and the absorbed blood weight was compared. This is Table 4.

Table 4 also shows similar measurement values for commercially available napkins (FIG. 9A).

Carboxymethylcellulose 8g Glycerin 80g Sodium chloride
10g bicarbonate of soda
distilled water
11 In the product of this invention, it is clear that the composite of compressed solid material and cellulose nonwoven fabric absorbs 95% of blood, and at the same time it is clearly compacted to a large width.

In addition, as can be seen from Figure 9, in the invented product, the solid part swells due to blood absorption, resulting in an increase in the thickness of the napkin, whereas in the commercially available napkin, the blood-sucking part goes down and the thickness decreases. .

Note: Numbers in parentheses in the structure column indicate the numbers in Figure 9.

(19) shows a compressed solid material wrapped in a nonwoven fabric.

[Brief explanation of the drawing]

FIGS. 1 to 3 each show the insertion shape of a compressed solid molded product of cellulose nonwoven fabric, with A being a cross-sectional view and the mouth being a schematic view seen from the top. FIGS. 4 to 6 each show the relationship between the shape of the original cellulosic nonwoven fabric and the shape of the expanded material. A is the shape of the original fabric, B is the folded or accumulated shape, C is the shape put in the mold, D is the shape after compression molding, E
indicates a shape that has been restored and expanded due to water absorption and blood absorption. FIG. 4 shows a square nonwoven fabric, FIG. 5 shows a tape-shaped nonwoven fabric, and FIG. 6 shows a strip-shaped nonwoven fabric. FIG. 7 illustrates an apparatus for condensing a required number of cellulose-based nonwoven fabric tapes, giving them appropriate twists, and rolling them up into a cheese shape using a compressed and solidified waist wine goo. FIGS. 8 and 9 schematically show the structure of a sanitary napkin before and after water absorption and blood absorption. The main symbols in the figure are as follows. 1... Turntable, 2... Can, 3... Tape-like material of cellulose nonwoven fabric, 4
...First focusing guide, 5... Second focusing guide, 6... Guide, 7... Compression roll, 8... Traverse Guide, 9... Curved wine goo, 10... Covering material, 11, 13... Curved pulp, 12... Compressed solid molded product of cellulose nonwoven fabric, 19... A compressed solid molded product of cellulose nonwoven fabric wrapped in cellulose nonwoven fabric.

Claims (4)

[Scope of utility model registration request] (1) In a sanitary napkin having a body fluid absorbing material made of at least one of paper cotton and cotton-like pulp inside, at least approximately the central part of the inside of the napkin is formed by compressed solid molding made of cellulose nonwoven fabric and having water absorption and recovery properties. The napkin is characterized in that objects are arranged thereon. (2) The sanitary napkin according to claim 1, wherein the compressed solid molded product is arranged so that at least the central part of the body fluid-absorbing surface of the napkin is raised. (3) The sanitary napkin according to claim 1, wherein the compressed solid molded product is a composite of a cellulose nonwoven fabric and a water-absorbing polymer powder. (4) Scope of utility model registration claims in which the volume and water retention rate of the compressed solid molded product are 60% or more, Paragraphs 1 and 2
The sanitary napkin according to item 1 or 3.