JP5196774B2 - Multi-layer absorbent hygiene articles - Google Patents

Description

  The present invention relates to a multilayer absorbent sanitary article without moisture reversion.

  A sheet used for absorbing body fluid such as a cage sheet and a sweat pad has a laminated structure mainly including a surface sheet, an absorber, and a back sheet. In such a sheet, a nonwoven fabric is generally used as the absorber (for example, Patent Document 1). The types of nonwoven fabrics are classified according to manufacturing methods such as a needle punch method, a spunlace method, a thermal bond method, a melt bond method, and an airlaid method. These nonwoven fabrics are widely used in the field of sanitary articles such as diapers and sanitary napkins because they are excellent in breathability and have a good touch.

However, in the case of conventional nonwoven fabrics, particularly when applied to thin sheets used for the purpose of absorbing body fluids such as cage sheets, there are many voids between fibers constituting the nonwoven fabric, so that sufficient moisture retention is obtained. There wasn't. That is, since moisture such as body fluids absorbed not only in the fibers but also in the gaps between the fibers is retained, when pressure is applied during use, the moisture present in the gaps between the fibers is reversed by the pressure, causing stickiness. It has been a problem to cause discomfort.
JP 2005-31990

  The main object of the present invention is to provide a multilayer absorbent sanitary article that does not revert moisture, has excellent breathability, and does not have stickiness and has a good touch.

  The present inventors have found that a multilayer absorbent sanitary article having no moisture reversal can be provided by using a nonwoven fabric containing a fiber containing a low melting point polymer and manufactured by a spunlace method as an absorbent. Further, it has been found that by using such an absorbent body, it is possible to use a nonwoven fabric for the back sheet, and further, it is possible to provide a multilayer absorbent sanitary article having excellent air permeability, no stickiness, and good touch.

The present invention provides the following multilayer absorbent sanitary articles.
Item 1. A multilayer absorbent hygiene article comprising an absorbent comprising fibers comprising a low melting point polymer and manufactured by a spunlace process.
Item 2. Item 2. The multilayer absorbent sanitary article according to Item 1, wherein the low melting point polymer has a melting point of 160 ° C or lower. Item 3. Item 3. The multilayer absorbent sanitary article according to Item 1 or 2, wherein the low melting point polymer is at least one selected from the group consisting of modified polyethylene terephthalate, polyethylene, and polypropylene.
Item 4. Item 4. The multilayer absorbent sanitary article according to any one of Items 1 to 3, wherein the absorbent comprises fibers having a core-sheath structure, and the sheath portion of the fibers is composed of a low melting point polymer.
Item 5. Furthermore, the multilayer absorptive sanitary article in any one of claim | item 1 -4 provided with the back sheet which consists of a nonwoven fabric.
Item 6. Item 6. The multilayer absorbent sanitary article according to Item 5, wherein the backsheet comprising the nonwoven fabric is a laminate of a nonwoven fabric produced by a spunbond method and a nonwoven fabric produced by a melt blow method.
Item 7. Item 7. The multilayer absorbent sanitary article according to Item 6, wherein the backsheet comprising the nonwoven fabric is a backsheet manufactured by SMMS (spunbond / meltblown / meltblown / spunbond).
Item 8. Item 8. The multilayer absorbent hygiene article according to any one of Items 1 to 7, which is a vaginal sheet, a sweat pad or a urine leak pad.

  The multilayer absorbent sanitary article of the present invention uses a nonwoven fabric produced by a spunlace method as an absorbent. Since the nonwoven fabric manufactured by the spunlace method exists with the fibers lying in the plane direction, moisture such as absorbed body fluid is quickly diffused. Moreover, since there are few voids between the fibers in the absorbent body, most of the water retained in the absorbent body is absorbed into the fibers. Therefore, according to the multilayer absorbent sanitary article of the present invention, moisture is retained in the fibers of the absorbent body even when pressure is applied when the sanitary article is worn, so that there is no reversal of moisture, stickiness during use, etc. No discomfort.

  Further, by incorporating a low-melting-point polymer into the nonwoven fabric produced by the spunlace method, fiber fluff due to body movement during use can be suppressed. Thereby, the state where there is little space between the fibers of an absorber can be maintained, and reversion can be prevented continuously.

  Furthermore, in this invention, since a water | moisture content is hold | maintained in the fiber of an absorber, a nonwoven fabric can be used for a back sheet. Therefore, it is possible to provide a multilayer absorbent sanitary article that has a further excellent breathability and has a better feel with improved stickiness.

  In the present invention, since a nonwoven fabric containing fibers containing a low melting point polymer produced by the spunlace method is used, the thickness of the absorber can be reduced, and the multilayer absorption is extremely thin and excellent in the feeling of use. Sexual hygiene articles can be provided.

  The multilayer absorbent sanitary article of the present invention has a multilayer structure in which a top sheet and a back sheet are laminated with an absorbent body interposed therebetween.

(1) Absorbent body The absorbent body constituting the multilayer absorbent sanitary article of the present invention contains fibers containing a low-melting polymer and is manufactured by a spunlace method.

Fiber containing low melting point polymer In the present invention, the fiber containing a low melting point polymer is a polymer having a melting point of about 160 ° C. or lower, preferably about 140 ° C. or lower, more preferably about 130 ° C. or lower, more preferably about 120 ° C. or lower. Refers to the fiber containing. The low melting point polymer used in the present invention is not particularly limited as long as it has such a melting point. For example, modified polyethylene terephthalate (modified PET), copolymerized polyethylene terephthalate (copolymerized PET), and the like, copolymer nylon And polyolefin resins such as polyethylene (PE) and polypropylene (PP), preferably modified PET, PE, PP and the like. In this invention, the fiber which consists of 1 type individually among these polymers may be used, and it can also be used as a fiber containing the low melting-point polymer which combines 2 or more types of polymers.

Moreover, the absorber using the fiber which has a core sheath structure in which the sheath part is comprised with the low melting point polymer as a fiber containing a low melting point polymer can be used for the multilayer absorptive hygiene article of this invention. As such fibers, conventionally known fibers can be used, and are not particularly limited. For example, polyethylene terephthalate (core portion) / polyethylene (sheath portion), polyethylene terephthalate (core portion) / modified polyethylene terephthalate (sheath portion) ), Polypropylene (core portion) / polyethylene (sheath portion), etc., preferably polyethylene terephthalate (core portion) / polyethylene (sheath portion), polyethylene terephthalate (core portion) / modified polyethylene terephthalate (sheath portion).

  The content of the fiber containing the low-melting polymer can be appropriately set according to the type of fiber used, the desired purpose, etc., as in the conventional product using the fiber.

  In the present invention, the low melting point polymer is desirably contained in an amount of about 10 to 80% by weight, preferably about 20 to 50% by weight, more preferably about 30 to 40% by weight, based on the total weight of the absorber.

  For example, depending on the type of the fiber containing the low melting point polymer, it can be set to a range of less than 20% by weight with respect to the total weight of the absorber, for example, about 5 to 9% by weight.

Structure of Absorber The absorbent body constituting the multilayer absorbent sanitary article of the present invention is configured by combining the fibers containing the above-mentioned low-melting polymer and a conventionally known material having absorbency and entangled them. The absorbent material is preferably an absorptive fiber and is not particularly limited as long as it has a melting point higher than that of the low melting point polymer.

  Examples of the water-absorbing fibers include natural fibers such as cotton, wool, and hemp; semi-synthetic fibers such as rayon fibers and acetate fibers; and blended and mixed products of various fibers. In order to increase the moisture retention of the absorber, it is preferable to contain cellulosic fibers such as rayon fibers and pulp fibers.

  Moreover, an absorber can also be manufactured by combining an absorptive polymer, an absorptive pulp, etc. with the fiber and absorptive fiber containing said low melting point polymer as needed. These materials also desirably have a higher melting point than the low melting point polymer.

  Examples of the water-absorbing polymer include acrylic acid-vinyl alcohol copolymer, acrylamide polymer, biocopolymer and the like.

  These synthetic fibers are not particularly limited by their cross-sectional structures and the like, and may have various structures represented by irregular cross-section fibers, porous fibers, porous water-absorbing fibers and the like.

  Further, the blending ratio of each fiber is not particularly limited as long as the effect of the present invention is achieved, and can be appropriately set according to the blending ratio of the low melting point polymer.

  Furthermore, if necessary, non-woven activated carbon, silica gel, deodorant, fragrance and the like can be added to the fiber containing the low melting point polymer or the absorbent fiber by a method such as impregnation or kneading into the fiber. Moreover, you may perform printing, application | coating, etc. using a pigment | dye etc. for an absorber.

  In this invention, the nonwoven fabric comprised by the fiber containing said raw material which has said absorbability, and a low melting-point polymer is used as an absorber. The nonwoven fabric used as the absorbent in the present invention is produced by a spunlace method. The spunlace method is a method of manufacturing a nonwoven fabric by using a high-speed jet water stream to interlace fibers with each other (for example, “Manufacture and application of nonwoven fabric” edited by Yoshio Nakamura, issued by CMC Co., Ltd.). In the spunlace method, a drying step (generally about 100 to 160 ° C., preferably about 120 to 160 ° C. is preferable when a low-melting polymer is contained) in order to entangle the fibers using a water stream. The

  In the present invention, the nonwoven fabric produced by the spunlace method exists in a state where the fibers in the absorbent body lie down in the plane direction, so that moisture such as absorbed body fluid is quickly diffused. In addition, since there are few voids between fibers in the absorbent body, most of the moisture retained in the absorbent body is absorbed into the fibers.

  Furthermore, by using a combination of a low melting point polymer and an absorbent fiber and producing a nonwoven fabric by the spunlace method, the low melting point polymer is melted in the drying step, and a state where there are few voids between the fibers can be maintained. Therefore, according to the multilayer absorbent sanitary article of the present invention, moisture is retained in the fibers of the absorbent body even when pressure is applied when the sanitary article is worn, and uncomfortable feelings such as stickiness do not occur during use. In addition, the gap between the fibers can be kept small continuously without fluff even during movement during use, and reversion of moisture can be prevented.

  Furthermore, in this invention, since a water | moisture content is hold | maintained in the fiber of an absorber, a nonwoven fabric can be used for a back sheet. Therefore, it is possible to provide a multilayer absorbent sanitary article that has a further excellent breathability and has a better feel with improved stickiness.

  Although it does not specifically limit as thickness of the absorber used in this invention, Usually, about 0.5-2 mm, Preferably it is about 0.6-1.5 mm, More preferably, it is about 0.7-1.2 mm. is there.

  As described above, the fibers are compressed by entanglement of the fibers with a water flow in the spunlace manufacturing method, the voids between the fibers are reduced, and the fibers are fixed in a compressed state by melting the low melting point polymer in the drying process. . Therefore, in the present invention, the thickness of the absorber can be reduced.

In addition, the basis weight of the absorbent body used in the present invention (weight per 1 m ^{2 of} fabric) is about 10 to 100 g, preferably 30 to 80 g, in order to maintain appropriate absorbency, water resistance, and usability. It is desirable that it is about 40 to 60 g.

(2) Backsheet The backsheet used in the multilayer absorbent sanitary article of the present invention is particularly a sheet or film having a liquid barrier property so that moisture such as absorbed body fluid does not pass through. Although it does not restrict | limit, it is preferable that it has moisture permeability and air permeability. As such a backsheet material, commonly used materials are widely adopted, and a hydrophobic material is desirable. Examples of the hydrophobic material include polyolefins such as polyethylene and polypropylene, polyester, nylon, polyvinyl alcohol, polystyrene, polyvinylidene chloride, and the like, or multilayer films thereof.

  Moreover, a nonwoven fabric can also be used as a back sheet of the multilayer absorbent sanitary article of the present invention. For example, in the case of a conventional cage sheet or the like, when a nonwoven fabric is used for the back sheet, there is a problem that body fluid such as an absorbed cage or the like is absorbed through body pressure. On the other hand, the multilayer absorbent sanitary article of the present invention uses the absorbent body as described in (1) above to enhance the moisture retention of the absorbent body. Therefore, in the present invention, even if a nonwoven fabric is used for the back sheet, moisture such as bodily fluid does not escape. Moreover, the air permeability of the multilayer absorbent sanitary article of the present invention is further improved by using a nonwoven fabric for the backsheet.

  As the non-woven fabric used for the backsheet, one made of the above hydrophobic material can be used. In addition, the method for producing the nonwoven fabric is not particularly limited as long as the effects of the present invention are not impaired. Preferably, the nonwoven fabric produced by the spunbond method and the nonwoven fabric produced by the melt blow method are two or more layers, more preferably four layers. It is desirable to use a laminate of the above. Examples of such a nonwoven fabric include SMMS (spunbond / meltblown / meltblown / spunbond), SM (spunbond / meltblown), and SMS (spunbond / meltblown / spunbond).

  The thickness of the backsheet used in the present invention is not particularly limited, but is usually about 0.05 to 1 mm, preferably about 0.1 to 0.6 mm, more preferably about 0.2 to 0.4 mm. is there.

  The basis weight of the back sheet used in the present invention is not particularly limited, but is usually about 10 g to 60 g, preferably about 20 g to 50 g, more preferably about 25 g to 45 g.

(3) Surface sheet In the present invention, the surface sheet is in direct contact with the body such as the local area (labial region, vaginal opening, etc.) and armpits, and passes through body fluids such as cages and sweat, and penetrates the lower absorbent body. It refers to those that have transparency. As long as this is the case, there are no particular restrictions on the type of material or the structure of the sheet. Examples of materials that can constitute such a surface sheet include synthetic fibers such as polyester fiber, polyamide fiber, acrylic fiber, polypropylene, polyethylene / polyester composite fiber, and polyethylene / polypropylene composite fiber; natural materials such as cotton, wool, and hemp. Fiber; or semi-synthetic fibers such as rayon fiber and acetate fiber; and blended and mixed fibers of various fibers. In order to maintain a duller surface, a synthetic fiber is preferable. The structure of the sheet is not particularly limited, and examples thereof include woven fabrics, knitted fabrics, nonwoven fabrics (including nonwoven fabrics composed of non-converging filament groups and short fiber groups), felts, and the like. Of these, non-woven fabric is preferred because it has elasticity and flexibility. The manufacturing method of the nonwoven fabric used for a surface sheet is not specifically limited, According to a conventionally well-known method, it can manufacture. Further, the top sheet may have a porous structure such as a mesh shape in order to increase the permeability of moisture such as body fluids, and the surface may be uneven by embossing or the like to improve the feeling of contact with the skin. It may be formed.

  Although it does not specifically limit as thickness of the surface sheet used in this invention, Usually, about 0.05-1 mm, Preferably it is about 0.1-0.6 mm, More preferably, it is about 0.2-0.4 mm. is there.

(4) Multilayer absorbent sanitary article The multilayer absorptive sanitary article of the present invention is not particularly limited as long as the effects of the present invention are not impaired, and is produced using a conventionally known method. As a manufacturing method, for example, a back sheet and a surface sheet are laminated with an absorbent body interposed therebetween, and after bonding these layers with an adhesive or the like, the outer peripheral portion is thermocompression bonded, and the sheet is punched out according to a desired shape. The method of cutting is mentioned. Further, it may have a layer made of other components on the back sheet, between the absorbent body and the top sheet, on the bottom surface of the back sheet, etc., for example, the bottom surface of the back sheet (ie, the adhesive surface to underwear or clothing). May have a pressure-sensitive adhesive layer, and may further include a release paper, a packaging sheet, and the like. A conventionally well-known adhesive agent can be used for an adhesion layer.

  Such a multilayer absorbent sanitary article can be applied to a cage sheet, a sweat pad, a urine leak pad, and the like.

  The shape of the multilayer absorbent hygiene article of the present invention is not particularly limited as long as the effects of the present invention are not impaired, but the multilayer absorbent hygiene article of the present invention is used as a cage sheet or a urine leak pad. In this case, for example, a small rectangle or a substantially rectangle is preferable. A rectangle is a quadrangle in which all apex angles are right angles, one side is longer than the other adjacent side, and the lengths of the opposite sides are equal. The substantially rectangular shape has a horizontally long (or vertically long) shape that is a characteristic of the rectangle, and examples thereof include an elliptical shape, a spindle shape, a gourd shape, and a trapezoidal shape (vertically long trapezoidal shape).

  Moreover, when the multilayer absorbent sanitary article of the present invention is used as a sweat pad, examples thereof include a circular shape, an elliptical shape, a gourd shape, and combinations thereof.

  The multilayer absorbent hygiene article of the present invention can be used in a size range that is usually applied to a vaginal sheet, a sweat pad, a urine leak pad, etc., and can be appropriately set depending on the application.

  The thickness of the entire multilayer absorbent sanitary article of the present invention is not particularly limited as long as the effects of the present invention can be achieved, but for example, about 0.6 to 3 mm, preferably about 0.8 to 2.7 mm, More preferably, it is about 1.1 to 2 mm.

  EXAMPLES Hereinafter, although an Example and an experiment example are given and this invention is demonstrated in detail, this invention is not limited to these Examples and an experiment example.

Examples and Comparative Examples Absorbers and back sheets were produced according to the compositions and methods shown in Table 1 below. Laminating an absorbent body between a surface sheet and a back sheet made of PET, PP, PP / PE, and bonding with an adhesive, the outer peripheral part is thermocompression-bonded and punched out. Example 1 and Comparative Examples 1 to 3 A sheet of cage was obtained.

Experimental example 1
(1) Moisture permeability According to JIS L 1099, the moisture permeability was determined by determining the amount (g) of water that passed per hour per 1 cm ² in the cage sheets of Example 1 and Comparative Examples 1 to 3. The larger the value, the higher the moisture permeability.

(2) Breathability The breathability was measured in accordance with JIS L 1096 by determining the amount of air (cm ³ / cm ² ) that passes through the cage sheets of Example 1 and Comparative Examples 1-3. The larger the value, the higher the air permeability.

(3) Reversion of moisture The moisture reversion in the cage sheets of Example 1 and Comparative Examples 1 to 3 was tested according to the following method.
1. A cage sheet provided with the absorber and the back sheet shown in Table 1 was prepared and cut into an area where the total absorption amount was about 1.3 g.
2. Above 1. After absorbing 0.5 ml of water on the sheet cut in step 1 and allowing it to stand for 1 minute, the filter paper whose weight was measured was placed on each sheet, and a 1.2 kg weight was placed thereon.
3. After 1 minute, the weight of the filter paper was measured, and the amount of water absorbed by the filter paper (ie, the amount of reversion) was calculated as a percentage. The larger the value, the greater the return amount.

(4) Cooling sensation The cooling sensation of the sheets of Example 1 and Comparative Examples 1 to 3 was tested according to the following method using Thermolab II (KATO TECH CO., LTD.). The cold feeling of touch refers to the feeling of being cold when touching a wet object.
1. The temperature of BT-BOX (Bottom Temperature Box) (1) is set to 25 degrees (assuming the outside temperature of the shorts).
2. The temperature of the T-BOX (Temperature Detecting Box) is set with BT-BOX (2) so that the temperature is 32 degrees (assuming skin temperature).
The surface sheet (side in contact with the skin) of the cage sheet cut to 3.2 × 2 cm absorbs 0.5 ml of water, and after 30 seconds, the surface sheet is on the BT-BOX (1). deep.
4). A T-BOX is placed on the top sheet and the q-max value is measured. The larger the q-max value, the cooler it feels at the time of contact.

The results of the above experimental examples (1) to (4) are shown in Table 2.

  It was shown that the container sheet of Example 1 has very little moisture reversion and low contact cooling feeling, and also has high moisture permeability and excellent air permeability. On the other hand, Comparative Example 2 (absorber is manufactured by the needle punch method) has a large amount of water reversal despite a large amount of rayon (absorbent fiber) and basis weight, and a cold feeling of contact is also implemented. It was found to be inferior to Example 1. Moreover, since the comparative example 1 uses the film for a back sheet, air permeability is inferior to Example 1, and there is also a reverse. Further, Comparative Example 3 was superior to Example 1 in terms of air permeability, but there was a reversion of moisture.

Experimental example 2 (monitor test)
Four samples of Example 1 and Comparative Examples 1 to 3 were prepared so that the total absorption amount was 1.3 g (Example 1: 24 cm ² , Comparative Example 1: 12.72 cm ² , Comparative Example 2: 8.24 cm). ² , Comparative Example 3: 6.95 cm ² ), and 0.5 ml of distilled water was absorbed into the cut sample. Thirty seconds after each sample was allowed to absorb distilled water, 12 subjects (female) were touched by hand, and the total score was calculated as 1 point, 2 points, 3 points, and 4 points in order of not getting wet. . The smaller the total score value, the less wet (no stickiness). The results are shown in Table 3 below.

Table 3 also shows that the cage sheet article of Example 1 has the least wetness (stickiness) in the monitor test.

Claims (11)

A multilayer absorbent sanitary article comprising an absorbent comprising fibers comprising a low melting point polymer and produced by a spunlace process , wherein the low melting point polymer has a melting point of 160 ° C. or less, and a spunlace The drying temperature in the drying step in the method is 120 to 160 ° C. The multilayer absorbent sanitary article according to claim 1, wherein the low melting point polymer has a melting point of 140 ° C or lower. The multilayer absorbent sanitary article according to claim 1 or 2, wherein the low melting point polymer has a melting point of 120 ° C or lower. The multilayer absorptive hygiene article according to any one of claims 1 to 3, wherein the absorbent contains 10 to 80% by weight of the low melting point polymer. The multilayer absorbent sanitary article according to any one of claims 1 to 4, wherein the low melting point polymer is at least one selected from the group consisting of modified polyethylene terephthalate, polyethylene and polypropylene. Absorber comprises a fiber having a core-sheath structure, the sheath portion of the fiber is composed of the low melting point polymer, a multilayer absorbent hygiene article according to any of claims 1 to 5. The multilayer absorptive hygiene article according to any one of claims 1 to 6, wherein the absorbent further contains absorbent fibers. Furthermore, the multilayer absorptive hygiene article in any one of Claims 1-7 provided with the back sheet which consists of a nonwoven fabric. The multilayer absorbent sanitary article according to claim 8, wherein the back sheet comprising the nonwoven fabric is a laminate of a nonwoven fabric produced by a spunbond method and a nonwoven fabric produced by a melt blow method. The multilayer absorptive hygiene article according to claim 9, wherein the non-woven fabric backsheet is a backsheet manufactured by SMMS (spunbond / meltblown / meltblown / spunbond). The multilayer absorptive hygiene article according to any one of claims 1 to 10, which is a cage sheet, a sweat pad or a urine leak pad.