KR101127784B1 - Topsheet of absorbent article - Google Patents

Abstract

The surface sheet 1 of an absorbent article consists of the spunlace nonwoven fabric 10 which apply | coated the softening agent. An absorbent article is an absorbent article used by being in contact with the wearer's skin when worn, and the surface contacting the wearer's skin is formed by the surface sheet 1 of the absorbent article described above.

Description

Surface sheet of absorbent article {TOPSHEET OF ABSORBENT ARTICLE}

1 is a perspective view showing a panty liner as one embodiment of the absorbent article of the present invention, wherein the surface sheet of the panty liner is one embodiment of the surface sheet of the absorbent article of the present invention.

FIG. 2 is a schematic cross-sectional view showing an enlarged cross-sectional structure of the surface sheet of the pantiliner shown in FIG. 1.

It is a figure which shows an example of the manufacturing apparatus and manufacturing method of the surface sheet which concerns on this invention.

4 is a view showing an example of a coating pattern in the case of pattern coating of the softening agent, Figure 4 (a) is an example of coating the softening agent in a dot pattern, Figures 4 (b) and 4 (c) is a stripe type Example coated with a pattern, FIG. 4 (d) shows an example coated with a lattice pattern.

Explanation of symbols on the main parts of the drawings

1: surface sheet 10: spunlace nonwoven fabric

11 coating part of softening agent 12 uncoated part of softening agent

20: panty liner (absorbent article)

The present invention relates to a surface sheet of an absorbent article and an absorbent article using the same.

As a surface sheet of absorbent articles, such as a panty liner and a sanitary napkin, the nonwoven fabric (spunlace nonwoven fabric) which flowed the hydrophilic fiber, such as rayon and cotton, is used frequently. Such a spunlace nonwoven fabric has a drawback that, in the manufacturing process, the fibers are severely tightened and hydrogen bonds are generated between the fibers, thereby making the paper feel stiff. In particular, in the case of a single layer spunlace nonwoven fabric, since a strength is required that does not cause surface destruction even when the liquid is sucked and wetted, a high basis weight web made of hydrophilic fibers is formed to entangle the fibers of the web with strong water flow. As a result, the sheet is hard and rough.

Japanese Laid-Open Patent Publication No. 2003-220660 discloses that a spunbond nonwoven fabric layer prepared by blending a softening agent in a raw material before melt extrusion is placed on the outer surface of an absorbent article for flexibility and smoothness.

However, when a softening agent is blended in the fiber raw material, problems such as a decrease in strength and discoloration due to the softening agent are likely to occur due to the blending of the softening agent.

The present invention provides a surface sheet of an absorbent article, which is made of a spunlace nonwoven fabric coated with a softening agent.

The present invention also provides an absorbent article which is used by being in contact with the wearer's skin when worn, and wherein the surface in contact with the wearer's skin is formed by the surface sheet of the absorbent article.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated, referring drawings based on the preferable embodiment.

The present invention relates to an absorbent article having excellent softness and softness in the surface sheet and skin contact surface of the absorbent article having excellent flexibility. The pantiliner 20 shown in FIG. 1 is one embodiment of the absorbent article of the present invention, and the liquid-permeable absorbent body 40 interposed between the liquid-permeable surface sheet 1, the liquid-impermeable back sheet 30, and both sheets. It is provided. And on the outer surface side of the back sheet 30, the shift | offset | difference prevention agent, such as an adhesive, and the peeling sheet (all not shown) which coat | cover and protect the shift | offset | difference prevention agent until use are formed in this order.

The surface sheet 1 of the pantiliner 20 is one embodiment of the surface sheet of the absorbent article of the present invention and, as shown in FIG. 2, is made of a single layer spunlace nonwoven fabric 10, and the form of the nonwoven fabric. Is mainly maintained by the entanglement of constituent fibers.

The spunlace nonwoven fabric 10 is coated with a softening agent.

The softening agent may be applied so as to spread widely throughout the thickness direction of the spunlace nonwoven fabric 10, but the side facing the wearer's skin side (hereinafter referred to as the skin contact surface side) or the side facing the wearer's skin side It is preferable that the coated portion is unevenly distributed on the surface side (hereinafter referred to as the skin non-contact surface side).

Even when the softening agent is unevenly distributed on either the skin contacting surface side or the skin non-contacting surface side, the flexibility of the surface sheet can be improved. However, when the softening agent is mainly applied to the skin non-contacting surface side, the softening agent itself has low hydrophilicity. The fall of the liquid absorbency at the skin contact surface side can be prevented.

On the contrary, when the softening agent is mainly applied to the skin contacting surface side, the smoothness of the skin contacting surface can be improved, and especially in the case of a thick surface sheet, even if the basis weight is about 35 to 100 g / m 2, for example, There is an advantage that can improve the smoothness of.

In the surface sheet 1 of this embodiment, as shown in FIG. 2, the softening agent is apply | coated to the site | part B from a non-skin contact surface to a predetermined depth, and the softening agent is not apply | coated in the surface vicinity of the skin contact surface side. Moreover, in the typical form in which the softening agent is mainly applied to the skin contacting surface side, the softening agent is applied to the site (for example, site A in FIG. 2) from the skin contacting surface to the predetermined depth, and the softening agent is softened in the vicinity of the surface of the skin non-contacting surface side. There is a form that I do not exist.

In the case where the softening agent is localized on either side of the nonwoven fabric, the spunlace nonwoven fabric is preferably 0.25 mm or more in thickness, in particular 0.3 to 1.5 mm, because the softening agent penetrates the softening agent appropriately and leaves an untreated layer in part.

The softening agent used in the present invention is one that is capable of sliding the fibers well at the interlacing point of the fibers of the spunlace nonwoven fabric, and is composed of αolefin sulfonate, acrylate / acrylamide copolymer, esteramide, and esteramide. Various waxes such as salts and paraffin waxes, various vegetable oils, various mineral oils, polyethylene glycols, water-soluble polyester resins, silicone oils, various silicone derivatives and the like can be used.

Among these, silicone-based softeners are particularly preferred from the viewpoint of particularly excellent flexibility and the softening agent to be supplied as an aqueous solution or an aqueous emulsion and excellent in workability. As silicone type softening agent, silicone oil, polyether modified silicone, amide polyether modified silicone, amino polyether modified silicone, oxazoline modified silicone, etc. can be used, Among these, polyether modification is excellent in the self-dispersibility as an aqueous dispersion liquid. Silicones, amide polyether modified silicones, aminopolyether modified silicones and oxazoline modified silicones are preferred. The softening agent can be used individually by 1 type or in combination of 2 or more type.

It is preferable that the softening agent is pattern-coated from the surface sheet of this invention from a viewpoint of improving flexibility, preventing the impairment of liquid permeability.

4 is a view showing an example of pattern coating of the softening agent, and the application part 11 of the softening agent is diagonally shown.

Fig. 4 (a) shows an example in which the softening agent is coated in a dot pattern, and the application portion 11 of the softening agent is formed discontinuously in both directions of the machine direction MD and its orthogonal direction CD when the nonwoven fabric is manufactured. have. Moreover, the shape of each dot can be made into arbitrary shapes, such as an oval, a triangle, a rectangle, a rhombus, in addition to circular.

Fig. 4B is an example of coating in a stripe pattern continuous in the CD direction and discontinuous in the MD direction. Fig. 4C is an example of coating in a stripe pattern that is continuous in the MD direction and discontinuous in the CD direction. Both ends of the stripe may or may not reach the end of the surface sheet.

Fig. 4 (d) shows an example of coating with a lattice pattern, in which a belt-shaped coating portion extending in the MD direction and a belt-shaped coating portion extending in the CD direction cross each other in a lattice shape.

In the case of pattern coating of the softening agent, the area ratio of the coating part 11 and the non-coating part 12 of the softening agent is that the coating part area ratio represented by the following formula (1) is 20 to 80%, in particular 30 to 60%. It is preferable from the viewpoint of achieving both excellent liquid permeability and high flexibility.

Area area (%) of coating area = total area / surface area of coating area 11 × 100 (1)

When the softening agent is not pattern-coated in a uniform pattern on the entire surface of the surface sheet, the sample for measuring the area ratio of the coated portion is 50 mm in length x 30 mm in width at the portion disposed opposite the wearer's excrement in the absorbent article. Take a sample of it.

Moreover, in the case of a pattern process, although the apply | coated softening material may be unevenly distributed on the skin contact surface side or the skin non-contact surface side, it can be used suitably, even if it is not unevenly distributed to either.

Moreover, the surface sheet of this invention is preferable even if the softening agent is irregularly coated (non-pattern coating) from a viewpoint of improving flexibility while preventing liquid permeability inhibition.

In particular, it is preferable that the part to which the softening agent was apply | coated in high concentration, and the part to which the softening material was apply | coated at low concentration are mixed on both surfaces or single side | surface of a surface sheet. The "high" here is the high which compared one with the other, and is relative.                     

In a particularly preferred embodiment, the high concentration portion to which the softening agent is applied at a high concentration, the low concentration portion to which the softening agent is applied at a lower concentration than the high concentration portion, and the portion to which the softening agent is hardly applied are mixed in a mosaic form.

In this way, at various coating concentrations, when various size portions are mixed in a mosaic shape, the softness of the flexible portion (parts having a large coating concentration) tends to extend to the whole sheet, and the portion which easily absorbs the liquid (the softener is not so much). Since the part which is not distributed) is distributed as a whole, absorption and a softening effect are compatible, and it is especially favorable.

Although the coating method of a softening agent can be widely used, such as dipping, gravure coating, and flexo coating which are normally performed, it kisses a predetermined amount of liquid with a roll beforehand, and electrodeposits it from a single side to a nonwoven fabric, and does not enter a drawing process. The coating method is most preferable because it can generate a suitable nonuniformity. In this case, it is advantageous that the roll pattern can be formed by a flat roll to form a random mosaic.

In either case, the nature of the effect lies in the planar nonuniformity softening agent concentration distribution, regardless of whether the coating is uniformly applied in the thickness direction, from the back side or the surface, or whether there is an uncoated layer. Moreover, even if an application | coating part is not localized on the skin contact surface side and the skin non-contact surface side, it can use preferably.

The softening agent is preferably coated in an amount of 0.03% to 3%, particularly 0.1% to 0.5% per weight of the surface sheet, in terms of adhesion amount sufficient to perceive the improvement of the feel, and is preferable from the viewpoint of low cost.                     

The application amount of the softening agent can be measured as follows.

(1) In terms of process control, the adhesion amount can be calculated from the consumption of chemical solution per unit time by knowing the weight per unit area (base weight, g / m 2), production rate, and concentration of the chemical liquid used.

(2) On the product (sheet), if the kind of the softening agent applied is known, analysis of the application amount and application state is possible. For example, in the case of a silicone type softening agent, the adhesion amount and adhesion state can be measured by Si fluorescence X-ray analysis of a sheet | seat. Alternatively, by means of NMR analysis on a suitable solvent extraction, the average amount of adhesion per unit area can be determined.

The coating amount of the softening agent, when the softening agent is a pattern coating (including irregular mosaic pattern), the average coating amount is the average concentration per unit area by NMR analysis or the like by appropriate solvent extraction, the adhesion amount distribution is, for example Si-imaging by fluorescence X-ray analysis, etc. can be understood.

The surface sheet of the present invention can be produced by, for example, nonwoven fabrication of a fibrous web by spunlace in a step of producing a spunlace nonwoven fabric, followed by application of a softening agent and then drying.

Fig. 3 shows a preferred example of a method for producing a surface sheet and a manufacturing apparatus according to the present invention, and in this method (apparatus), a suction drum is provided for a fibrous web 10 'made of cotton fibers produced by a carding machine. The high pressure jet stream W is acted on one side of the net on the net of 2A, and the high pressure jet stream W is acted on the net of the suction drum 2B from the opposite side, and the obtained wet state is thus obtained. The nonwoven fabric 10 of the nonwoven fabric 10 is inserted into the space between the rolls 3 and 3 to be pressed and dehydrated appropriately. Then, the coating agent of the roll coating method is applied to one side of the nonwoven fabric 10, so that the softening agent is an aqueous solution or an aqueous emulsion. It is apply | coated as (4). And the surface sheet which concerns on this invention is obtained by drying the nonwoven fabric to which the softening agent was apply | coated by the well-known drying equipment 6.

In the method (apparatus) shown in FIG. 3, the coating apparatus of the kiss coat system is used, The aqueous solution or water-based emulsion (4) containing a softening agent is apply | coated to the nonwoven fabric 10 by the single roll 5, have. The manufacturing method of the surface sheet of this invention is not restrict | limited at all as long as the structure can be implement | achieved, For example, using coating equipment, such as a gravure coat or flexographic system, instead of the coating apparatus of a kiss coat system, The surface sheet in which the softening agent was coated in the whole thickness direction of the nonwoven fabric 10 can also be obtained. Moreover, the pattern coating of a softening agent can be implement | achieved by providing the unevenness | corrugation of a predetermined pattern to the surface of the member (the said roll 5 etc.) which makes contact with the nonwoven fabric of coating equipment. Spray coating etc. may be sufficient as the coating method of a softening agent.

Examples of the constituent fibers of the spunlace nonwoven fabric include staples composed of hydrophobic short fibers such as polyethylene terephthalate (PET) fibers and polypropylene (PP) fibers, split fibers such as PP / polyethylene glycol (PEG) and PET / PEG, and rayon. Regenerated cellulose fibers such as cupra, natural fibers such as silk and cotton, and the like. However, the effects of the present invention are further remarkable when the hydrophilic fibers, in particular, cotton and / or rayon are mainly used.                     

When the constituent fibers of the spunlace nonwoven fabric mainly consist of cotton and / or rayon, hydrophobic synthetic fibers, for example, PET fibers, for the purpose of improving the strength or increasing the volume (thickness) of the nonwoven fabric. , PP fibers, PET / polyethylene (PE) composite fibers, etc. may be blended in small amounts. In view of this purpose, it is preferable that the compounding quantity of hydrophobic synthetic fiber is about 2 to 20 weight% with respect to the weight of the whole constituent fiber. In this case, it is preferable that the compounding quantity of cotton and / or rayon is 80 to 98 weight% with respect to the weight of the whole component fiber. As for hydrophobic synthetic fiber, it is more preferable to use this by making it hydrophilic.

The softened surface sheet preferably has a bulk softness of 1.9 to 29.4 cN, in the case of a sheet of 30 g / m 2 or more having sufficient strength alone as a spunlace. It is more preferable that is. In particular, when the constituent fibers of the spunlace nonwoven fabric are cotton or rayon, the bulk softness is preferably 2.9 to 19.6 cN, more preferably 4.9 to 14.7 cN.

Here, the bulk softness can be measured as follows.

 <Measurement of Bulk Softness>

From the softened surface sheet, five rectangular samples of 30 mm are cut out in 150 mm x width direction (CD direction) in a loosening direction (MD direction). Each sample was made to have the length direction become a circumferential direction, 5 mm of both ends of a longitudinal direction overlap, and the cylinder of diameter 45mm is made, and the upper part (top of a cylindrical axial direction) and the lower part of the part which overlapped both ends are stapled. (For example, the needle of Max Corporation No. 10-1M) is fixed and attached, and a cylindrical measurement sample is obtained. In addition, the direction of the needle is made parallel to the circumferential direction.

The obtained measurement sample (initial sample width; 30 mm) was set in a tensilon compression tester (Oritec Co., Ltd., "RTA-100"), and the cylindrical axial direction (sample) was carried out by the circular compression plate of diameter 70mm or more. Width direction), the maximum load at the time of compression at a compression speed of 10 mm / min is measured. The same measurement is made about 5 samples and the average value is calculated | required.

This invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the meaning of this invention.

For example, the absorbent article in the present invention may be an absorbent article other than a panty liner, and other examples of the absorbent article used in contact with the wearer's skin when worn include sanitary napkins, disposable diapers, incontinence pads, and breast milk absorbers. Pads etc. are mentioned.

In addition, the constituent material of the absorbent article of the present invention is not particularly limited except for the surface sheet. For example, as the constituent material of the absorber and the back sheet in the pantiliner 20 described above, What is conventionally used by the kind of article can be used. For example, a fiber aggregate (fiber web, nonwoven fabric, etc.) consisting of pulp fibers or thermoplastic fibers, or an absorbent polymer held therein in a layered or dispersed state may be used as the absorbent body. As the back sheet, polyethylene, Films of thermoplastic resins such as polypropylene, polyvinyl acetate, polyester, water-repellent spunbond nonwovens, and multi-layered nonwoven fabrics of spunbond-meltblown spunbonds can be used.                     

Also disclosed herein is an invention that effectively applies the effect of a softening agent to a spunlace nonwoven fabric.

In order to be more flexible, you may add a calender roll immediately after spunlace or just after spunlace and just after drying, and may add a massage treatment.

As described above in detail, the surface sheet of the absorbent article of the present invention can provide a surface sheet having sufficient strength and excellent in flexibility.

According to the absorbent article of the present invention, it is possible to provide an absorbent article having a soft skin contact surface and excellent touch.

Claims (9)

The softening agent is irregularly mixed so that a high concentration portion in which a silicone softening agent is applied at a high concentration, a low concentration portion in which a softening agent is applied at a lower concentration than a high concentration portion, and a portion in which the softening agent is hardly applied are mixed in a mosaic form. It consists of a spunlace nonwoven fabric coated with a pattern, The softening agent is applied to the spunlace nonwoven fabric in the wet state, whereby the respective parts are mixed in a mosaic shape, A surface sheet of an absorbent article, wherein a softening agent is applied at 0.03% to 3% per weight of the surface sheet. 2. The surface sheet of an absorbent article according to claim 1, wherein the amount of the softening agent applied to the side opposite to the wearer's skin side is greater than the amount of the softening agent applied to the face facing the wearer's skin. 2. The surface sheet of an absorbent article according to claim 1, wherein the amount of the softening agent applied to the surface facing the wearer's skin is greater than the amount of the softening agent applied to the opposite surface facing the skin side of the wearer. 2. The surface sheet of an absorbent article according to claim 1, wherein the softening agent is applied and formed only on the surface side opposite to the surface facing the wearer's skin side. The surface sheet of the absorbent article according to claim 1, wherein the constituent fibers of the spunlace nonwoven fabric are mainly cotton and / or rayon. The surface sheet of the absorbent article according to claim 1, wherein the silicone-based softening agent is polyether modified silicone, amide polyether modified silicone, aminopolyether modified silicone, oxazoline modified silicone, or a mixture thereof. An absorbent article used by being in contact with the wearer's skin when worn, wherein the surface in contact with the wearer's skin is formed by the surface sheet of the absorbent article according to claim 1. delete delete

Images