JPS61170462A - Absorbing body of tampon - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an absorbent body for a tampon for menstrual treatment, and more specifically, the fiber density in the front part of the absorbent body is lower than the fiber density in the rear part to absorb menstrual blood. This invention relates to a tampon absorbent body that improves the initial absorption rate and reduces the amount of fibers that fall off when the tampon is taken out.

[Conventional technology and problems]

Generally, this type of tampon is made by compression molding water absorbent fibers into a cylindrical shape, and when inserted into the vagina, it gradually absorbs menstrual blood from the tip and gradually swells from the tip. ing. However, in order to absorb enough menstrual blood and make it easier to insert it into the vagina, compression molding is done to increase the amount of fiber and have a high fiber density. The tampon was slow and had difficulty swelling, and in some cases menstrual blood could leak down the sides of the tampon.

As an invention to solve these drawbacks,
The method described in Japanese Patent No. 583 is disclosed.

This known method reduces the density of the tip of the absorbent body of a tampon to 0.
．． 2-0.8 g/crA, rear end density 0.8-1
．． 5 g/aa, and the length of the tip portion occupies 1710 to 1/2 of the total length of the absorbent body of the tampon. However, although tampons manufactured by this known method have a fast absorption rate and a large amount of absorption for low-viscosity liquids such as water, they cannot absorb high-viscosity liquids such as menstrual blood. The absorption rate is not fast enough to overcome the disadvantages of conventional tampon absorbers as described above. The reason for this is that water-absorbent fibers such as rayon used in tampon absorbers generally have oil agents (
Finishing agent) has been applied, and the adhesion of oil may interfere with the absorption of menstrual blood, and the density of the rear end is 0.8
-1.5 g/aA, the fiber density is too high and menstrual blood is difficult to absorb. Oils are attached to fibers for various purposes such as spinning, knitting, dyeing, and antistatic purposes, and the attachment of oils is essential for processing suitability.

In addition, the absorber of conventional sanitary tampons has a basis weight of -i of 30
A method of compression molding a fibrous web with a weight of about 0 to 1000 g/rrr as it is or folding it in the diametrical and lengthwise directions, or a method of forming a thin fibrous web with a basis weight of about 4゜gird into a spiral shape and forming it in the diametrical direction. It is manufactured by a method such as compression.

However, fibrous webs generally consist of microfibers (fiber waste) and fiber webs.
Since it contains short fibers with a diameter of 0+am or less, and there is little intertwining of the fibers, there is a drawback that when the tampon is taken out after use, the fibers fall off and remain in the vagina. More specifically, due to the contact between the tampon inserted into the vagina, which swells by absorbing menstrual blood, and the vaginal wall, and the frictional resistance during removal, some of the fibers that make up the absorbent body of the tampon, especially the outer circumferential surface of the tampon, are damaged. The drawback was that some of the constituent fibers fell off and remained in the vagina.

As a solution to the above-mentioned drawbacks, Japanese Patent Laid-Open No. 49-59498 discloses a method of gathering fiber webs by needling. However, although this method improves the intertwining of fibers, needling using metal needles damages the fibers, shortens the length of the fibers, and increases the proportion of short fibers. Alternatively, a new drawback arises in that the needle may break and become mixed into the absorbent body of the tampon.

Further, there is a proposal in Japanese Utility Model Publication No. 59-25376 that focuses on the method of joining the retrieval string, but it is insufficient in particular in terms of dropping of fine fibers (fiber waste) and short fibers.

As mentioned above, the absorbers of conventional sanitary tampons include:
It had the following drawbacks.

■The initial absorption rate is slow for highly viscous liquids such as menstrual blood.

■A large amount of fibers fall off when removing the tampon after use.

[Means for solving problems]

The present inventors have completed the present invention as a result of intensive research to solve the above-mentioned problems.

That is, the present invention provides a tampon absorbent body which is formed by jetting a liquid onto a fiber laminate mainly composed of water-absorbing fibers to form a sheet-like material in which fibers are entangled, and then compression-molding the sheet-like material. The absorbent body comprises a first part forming a front part and a second part forming a rear part, and the fiber density of the first part is lower than the fiber density of the second part. The present invention provides an absorbent body for tampons.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

In the present invention, a fiber laminate (
The fibrous web) is formed by spinning cards or garnet or other equipment.

The fibers can be arranged almost parallel to the length of the web (parallel-1 aid), or the web can be folded and arranged cross-wise (cross-1a).
id), etc., and a fiber laminate 1 as shown in FIG. 1 is formed by these methods. Furthermore, the fiber laminate 1 used in the present invention can also be obtained by a method such as air-laying in which the fiber arrangement is random and has no directionality.

The fiber laminate 1 thus obtained is conveyed by a belt 4 to a liquid jetting step. In the liquid jetting step, a liquid is jetted onto the fiber laminate 1 from the direction of arrow 2 shown in FIG. The liquid is generally water, but in the present invention, since the purpose is to wash away oils adhering to the fibers, heated water such as warm water or hot water is more effective than water. There are many. After the liquid is injected in this manner, it is dried by a drying device 13 to obtain a fiber sheet-like material 3 in which fibers are entangled. In the present invention, the degree of entanglement of the fibers constituting the fiber sheet material 3 is important, and it is also important to wash off the oil adhering to the fibers. It is preferable that the pressure is 10 kg/aa or more, and fiber sheet-like products manufactured at a pressure lower than this have a low degree of fiber entanglement, and when compression molded into a tampon absorbent body and used, a large amount of fibers will fall off. The cleaning effect of the oil solution cannot be expected to be very high.

In addition, fine fibers (fiber waste) contained in the fiber laminate and 10
Since the effect of removing short fibers of about mm or less becomes insufficient, such short fibers will fall off when the tampon is formed into an absorbent body and used.

The type of water-absorbent fibers constituting the fiber laminate of the present invention may be of any kind as long as it is generally used in tampon absorbers.
Examples include rayon, absorbent cotton, or mixtures thereof. Further, a small amount of hydrophobic fiber may be mixed. There is no particular restriction on the fiber diameter, but since it is used in the absorbent material of tampons, a diameter of about 1 to 5 denier is appropriate from the viewpoint of water absorption performance. Regarding the fiber length, from the purpose of the present invention to reduce the amount of shed fibers, 20ma+
The above are suitable, and more preferably 30w+s or more.

The basis weight of the fiber laminate 1 to which the liquid is sprayed varies depending on the shape of the tampon absorber obtained by compression molding, but is not particularly limited.

In the method of entangling fibers by jetting a liquid as described above, the degree of fiber entanglement may be affected by the shape of the nozzle used when jetting the liquid, but the water-absorbing fiber of the present invention When making a sheet-like product mainly consisting of
The nozzle may have any shape. Also, as shown in Fig. 2, different directions 2.2° and 2#
For example, a method can be exemplified in which the fibers are efficiently entangled by injecting the liquid from the fiber laminate 1 or by injecting the liquid from both the upper and lower sides of the fiber laminate 1 simultaneously or separately.

An example of the state of the tampon absorbent body of the present invention before compression molding is shown in FIGS. 3 and 4. the second regions 6 forming the respective shaded parts, i.e. the rear part of the absorbent body of the tampon;
The fiber density of the tampon is higher than that of other parts, and the first part 5, which forms the front part of the absorbent body of the tampon and which comes into contact with menstrual blood quickly when inserted into the vagina, has a lower fiber density. ing. In this way, in order to create high and low fiber densities in the fiber laminate that is compression-molded into the absorbent body of a tampon, it is sufficient to vary the injection pressure of the liquid against the fiber laminate depending on the part of the fiber laminate. can be made high-density, and parts with low injection pressure can be made low-density. Alternatively, by varying the number of times the liquid is sprayed onto the fiber laminate depending on the portion of the fiber laminate, the portions where the liquid is sprayed many times can have a high fiber density, and the portions where the fluid is sprayed less often can have a lower fiber density.

FIG. 5 shows a perspective view of an example of a fiber sheet-like product in which fibers are entangled, obtained in this way. and then compression molded to form a tampon as shown in Figure 6. According to the method described above, the low fiber density portion 5 of the fiber sheet
is thicker and thinner in the high fiber density region 6 (FIG. 5), which is advantageous for tampons.

The reason for this is that when the absorbent body of a tampon, which is a compressed fiber product, absorbs menstrual blood, it tends to return to the shape of the fibrous sheet before absorption. This is because the volume is smaller than that of the front portion and can be easily taken out.

The second method for producing high and low fiber density is the seventh method.
A fiber laminate 10.10' with an appropriate basis weight as shown in Figure (a)
, 10'' are superimposed and then a liquid is injected to form a fiber sheet of almost uniform thickness as shown in Fig. 7. In this way, the shaded area 6 has a fiber density Since the fiber density is low in the other portion 5, the tip portion has a high absorption rate when processed into an absorbent material for a tampon.

Next, other embodiments will be described. As shown in FIG. 8, a rectangular fiber sheet 11 with fiber density at both ends 5,5'' lower than that in the center 6 is formed by the method described above, and the sheet 11 is As shown in Fig. 9, the two sheets are stacked in a cross shape, a string 7 is attached to the center part 12, and the part is made to protrude so as to become the rear end.
This is a tampon similar to that shown in FIG. 6, obtained by compression molding. As can be seen from the manufacturing process, these tampons have the excellent feature that when they absorb menstrual blood, they swell and open like a parachute, making it difficult for menstrual blood to leak, and they are also easy to take out after use. Now consider the fiber density of a tampon. As mentioned above, in the tampon of the present invention, as shown in FIG. 6, the fiber density of the first part 8 forming the front part is lower than the fiber density of the second part 9 forming the rear part. However, as shown in Table 1, there are several types of tampons with different densities in the first and second parts of the tampon absorbent body and the volume ratio of each tampon absorbent body to the entire absorbent body. An experiment was conducted in which a tampon absorber as shown in FIG. 3 was prototyped and the absorption rate was measured using the three types of test liquids shown below.

The test conditions are as follows.

1) Liquid injection method: 50°C warm water is sprayed from a nozzle with a diameter of 0.16mm to 40~8cm.
It was injected at a pressure of 0 kg/-. The distance between nozzles is 0.16
71III.

2) Tampon size: diameter 11 vs. length 50mm
3) Fiber used: Rayon 3 denier 51++++w4
) Test solution: [Water] Congo red aqueous solution 4 cps (25°C) [Blood A] Horse defibrinated blood, viscosity 2BCI)! (25℃) [Blood B] Horse defibrinated blood Viscosity 83 cps (25℃) 5) Test method: Place a tampon into an elastic rubber tube with an inner diameter of approximately 10 mm, and insert the tampon with the tip of the tampon facing upward. Pour 5 g of the test liquid into the tip of the tube at once and measure the time it takes for the test liquid to be completely absorbed.

6) Calculating density: Divide the tampon into two parts on the side where the density changes rapidly.
The average density of the first part forming the front part, the second part forming the rear part, and the average density of the entire tampon absorbent body were calculated.

The test results are shown in Table 1.

From the results in Table 1, when the test liquid is water, the fiber density of the first part of the absorbent body of the tampon is not lower than that of the second part (N18.10), and the first part Even though the second part has a fairly high density (N19.10), the absorption rate is fast (it appears to be excellent as a tampon absorber).

However, the menstrual blood that is actually to be absorbed has a high viscosity (and a tampon absorbent material that has a high absorption rate for highly viscous liquids such as blood A and blood B is desirable).

As can be seen from the comparison between No. 4 and No. 7 in Table 1, the absorption rate of the tampon absorbent body of the present invention is fast because the amount of oil adhesion is reduced by jetting the liquid. Furthermore, the fact that the density of the first region is low also has a positive effect on the absorption rate.

Also, the fiber density of the first part of the absorbent body of the tampon is 0.5.
g/cm3 or less is preferable, and 0.2 to 0.4 g/cm3 or less is preferable.
aa is more preferred. The fiber density of the second part is 0.5~
0.8 g/ad is suitable. Furthermore, the average density of the entire tampon absorber is preferably 0.7 g/cm3 or less; tampon absorbers with an average density higher than this are inherently slow in absorbing highly viscous liquids such as menstrual blood, and the tampon's absorbency is Menstrual blood often leaks down the sides. On the contrary, the first part,
For both the second part, the average fiber density is, for example, 0.2 g/c.
m3 or less (if this is the case, the absorption rate is fast even for blood without using the liquid-sprayed fiber sheet as in the present invention. However, the absorbent body of such a tampon has a low absorption amount. (This is unsatisfactory as a tampon. Also, as a result of experiments, the volume ratio of the first part to the entire tampon absorbent body should preferably be 30% or more, and 40 to 7
It was confirmed that 0% is the most appropriate. When the volume ratio of the first site was less than 30%, the initial absorption rate of menstrual blood was slow, and when it exceeded 70%, the amount of absorption tended to be relatively small.

〔Effect of the invention〕

As described above, in the tampon absorber of the present invention, the fiber density of the first part forming the front part is higher than that of the second part forming the rear part.
Since the fiber density is low compared to the fiber density in the area of It absorbs without leaking even if it is discharged all at once. In addition, since the absorbent body of the tampon of the present invention is formed by spraying a liquid onto a fiber laminate, the fiber sheet-like material is compression-molded into the absorbent body.
It contains a small proportion of fine fibers and short fibers (the amount of fibers that fall off from the tampon during use is much lower than that of conventional tampon absorbers.

It goes without saying that the present invention also includes a tampon in which the absorbent body of the present invention is loaded into a so-called applicator (insertion tool).

[Brief explanation of drawings]

Figures 1 and 2 are schematic cross-sectional views showing the manufacturing process of the fiber sheet used in the tampon of the present invention, and Figures 3 and 4 are compression molding of the absorbent body of the tampon of the present invention. FIG. 5 is a perspective view showing an example of a fibrous sheet-like material used in the present invention, FIG. 6 is a front view showing an example of a tampon according to the present invention, and FIG. 7 is a perspective view showing an example of a tampon according to the present invention. It is a perspective view which shows another example of the fiber sheet-like material used for a liquid, (a) is a view before the liquid is injected, (b) is a view after it is injected. 8th
This figure is a perspective view showing still another example of the fiber sheet-like material used in the present invention, and FIG. 9 is a perspective view showing the state when this fiber sheet-like material is compression-molded. 1: Fiber laminate 2.2", 2": Arrow indicating liquid jet direction 3: Fiber sheet 4: Belt 5.5': Low density portion of fiber sheet 6: Height of fiber sheet Density part 7: String 8: Low density part 9: High density part 10, 10', 10'': Fiber laminate 11: Rectangular fiber sheet 12: Center part 13: Drying device Fig. 1 Fig. 2 Fig. 3 Figure 4 Figure 6 Figure 5 Figure 7 (a) (b) Figure 8 Figure 9

Claims (1)

[Claims] 1. Forming a sheet-like material in which fibers are entangled by spraying a liquid onto a fiber laminate mainly composed of water-absorbing fibers;
A tampon absorbent body formed by compression molding the sheet-like material, the absorbent body comprising a first part forming a front part and a second part forming a rear part, the fiber density of the first part being A tampon absorbent body, characterized in that the fiber density of the second region is lower than that of the second region. 2. Absorption of the tampon according to claim 1, wherein the average fiber density of the first region is 0.5 g/cm^3 or less and the overall average fiber density is 0.7 g/cm^3 or less body. 3. The volume of the first part is 30 to 70 of the volume of the entire absorber.
% of the tampon absorber according to claim 1 or 2.