WO1986005661A1

WO1986005661A1 - Disposable diaper having improved dry-touch properties

Info

Publication number: WO1986005661A1
Application number: PCT/JP1985/000157
Authority: WO
Inventors: Fusayoshi Masuda; Koji Mita; Sotoru Tachi
Original assignee: Sanyo Chemical Industries, Ltd.
Priority date: 1985-04-01
Filing date: 1985-04-01
Publication date: 1986-10-09

Abstract

Disposable diaper having improved dry-touch properties (no urine-wet feeling on skin), which comprises a liquid permeable outer material layer (1) and a highly water-absorptive resin layer (3) having inserted therebetween a synthetic fiber cotton mass layer (2) of a specific thickness and a specific weight ratio.

Description

Description Use dry diapers with improved dryness

Technical field

TECHNICAL FIELD The present invention relates to a disposable disposable diaper having improved ease of wearing.

Background technology

Recently, water-absorbing polymers have begun to be used as a part of absorbent materials for disposable diapers to increase the liquid absorption and retention of urine and other excrement. Absorbents containing these polymers have a liquid absorption capacity and liquid retention capacity that is 5 to L0 times higher than conventional absorbent materials such as water-absorbing paper or cotton-like valves. Is recognized. However, it is hard to say that the degree of the improvement is sufficient compared with the absorption and retention of the superabsorbent polymer itself. In other words, in this case, since the superabsorbent polymer coexists with the conventional absorbent, such as water absorbent paper and a cotton-like valve, the liquid to be absorbed is not only superabsorbent polymer but also water absorbent paper with low liquid holding power. This is because the liquid absorbed by the water-absorbent paper and the valve leaks to the surface when pressure is applied to the absorbent article, and therefore, the skin of the part where the diaper is worn is There is a disadvantage that it is wet with urine and gives discomfort. Furthermore, since the superabsorbent polymer forms a gel at the first urination and does not pass through the urine later, the spread of the liquid is prevented, and there is a disadvantage that the absorption capacity of the entire disposable diaper is not effectively used. .

Eliminates the discomfort of wet skin Jf, which is a drawback of the conventional diapers, and keeps the skin dry as always (hereinafter referred to as dry touch) As a result of diligent studies on a disposable disposable diaper that keeps its shape, that is, a disposable disposable diaper that does not exude urine on the contact surface with the skin even when pressure is applied, and that can effectively utilize the retained absorbing power, the present inventors have reached the present invention.

Disclosure of the invention

That is, the present invention provides a liquid-permeable exterior material layer (1), a superabsorbent polymer or an absorbent layer (3) comprising 80% by weight or less of absorbent starvation, and a liquid-permeable exterior material layer. The absorbent composite of (6) is further provided with a thickness of 2 to 10% between the (1) layer and the (3) layer, which is composed of a synthetic fiber having a ratio of 10 to 50% by weight based on the weight of the (3) layer. A disposable disposable diaper having an improved dry-tatch property and a method for improving the dry-tatch property of the disposable diaper, characterized by having a low-profile layer (2).

In the present invention, the liquid-permeable exterior material layer (1) to be used is not particularly limited as long as it is usually used. For example, cloth, paper, non-woven fabric, liquid-permeable synthetic film, or any of these materials can be used. And a complex. More specifically, the nonwoven fabric is made of paper, rayon polyester, polypropylene, or the like, and has a basis weight of 10 to 20 g nom 'and a thickness of 0.05 to 1 mm.

In the absorbent layer (3) of the present invention, the highly water-absorbing polymer is a resin that is insoluble in water and has a water absorption capacity of 60 ml or more, and has a shape such as powdery powder, sheet bark, or fibrous shape. However, any of them can be used.

Examples of the water-absorbing polymer include starch or cellulose (a), a water-insoluble monomer, a monomer that becomes water-soluble by Z or hydrolysis, and a crosslinking agent (c) as essential components. However, there are resins that can be obtained by avoiding water as necessary. Details of (a), (b) and (c), the mixing ratio of (a), (b) and (c), the production method, and specific examples of the water-absorbent resin used in the production of the above resin are described in No. 25886, JP-B-53-46199, JP-B-53-46200 and JP-B-55-21041.

Examples of other resins include those obtained by polymerizing (and (b), such as a starch-acrylonitrile graphite polymer hydrolyzate, cellulose-acrylonitrile graphite, and the like. Hydrolysates of polymers, etc .; copolymers of (II) and (c), such as cross-linked polyacrylamide and its partial hydrolysates, cross-linked sulfonated polystyrene, cross-linked Bhopal, saponified cross-linked vulester-unsaturated rubonic acid copolymer, cross-linked boria acrylate and acrylic acid described in JP-A-52-14689 and JP-A-52-274β5 Examples include acrylate copolymers, cross-linked isobutylene-mono-maleic anhydride copolymers, and cross-linked polyethylene oxide. ¾) Polymer, for example, self-crosslinking boria Crylate, a resin described in JP-B-54-30710 and a polymer having at least a hydroxyl group and a carboxylate group in the molecule, for example, a resin described in JP-B-54-37994 can also be used. Two or more of the above resins may be used.

Examples of the absorbent fibers include conventionally used cotton wool valves, absorbent paper, cloth, gauze, and rayon nonwoven fabric.

(4) The amount of the water-absorbing polymer used is usually 10 to 100%, preferably 20 to 60%, based on the weight of the absorbent. If the amount of the superabsorbent polymer is small, bleeding of the upper part when pressure is applied to the absorbent article tends to occur.

The absorbent of the present invention includes a superabsorbent polymer and a conventional absorbent. When used together with flocculent pulp, a method of mixing the two, a method of mixing the two and then forming a sheet by pressurizing in the presence of water, and a method of forming a highly absorbent polymer on the cotton pulp layer Can be applied, and if necessary, a method of laminating floc pulp can be applied ^

When using a super absorbent polymer and absorbent paper, cloth, gauze, or non-woven fabric made of rayon, etc., use a binder or a binder if necessary after spraying the super absorbent polymer between these two materials. It is common to pressurize in the presence of water.

(3) In the layer, non-absorbable substances, for example, synthetic fibers such as polyester and polypropylene, or nonwoven fabrics or webs thereof; inorganic particles such as calcium carbonate and clay; fragrance; An odorant; an admixture of an ultraviolet ray inhibitor or the like may be added as long as the absorption performance of the absorber is not impaired.

The liquid-impermeable exterior material layer (6) of the present invention is not particularly limited as long as it is impermeable to liquid and flexible, but usually a synthetic resin film such as polyethylene is used. Is done.

Examples of the synthetic fibers of the present invention include polyacrylonitrile, polyacrylic fiber and poly (vinyl chloride) -based copolymers such as polyacrylic fiber, Nylon 6, and Nylon 66. Polyamide fibers such as Nylon 11; polyesters such as poly (ethylene terephthalate) and polyoxybenzoic acid; vinyl fibers such as poly (vinyl chloride) and poly (vinylidene chloride); poly (ethylene, polypropylene); Can be used for fiber-reinforced cotton such as poly-or-olefin and other borio-refined fibers, polytetrafluoroethylene, fluorine fiber such as polytetrafluoroethylene, polyurethane fiber such as Svandex, etc. . These fibers have a water adsorption of 10% by weight The following hydrophobic fibers must be used, and the more preferable adsorption amount is 7% or less. In order to maintain the distance between the (1) and (3) layers large and to improve the urinary diffusion of urine without impairing the liquid permeability, a sheet fleece-like mass (hereinafter referred to as web It is used for

The amount of synthetic fiber used is usually 200 g / nf of SOgZnf, preferably 50-120 g / nf, and the thickness is 2-15 ", more preferably 3-8". When the amount used is less than 30 g nom ', the effect of using synthetic fiber is small, and the effect does not change even when it exceeds 200 g / nf. -As the above-mentioned web-like synthetic fibers, fibers that have been surface-coated or treated with a surfactant using a hot-melt fiber or a binder can also be used.

The method for forming the synthetic fiber layer (2) of the present invention between the (1) layer and the (3) layer is not particularly limited as long as it can be carried out. In a disposable paper diaper manufacturing apparatus that sandwiches the sheet-like layer made by the method described above, a method of laminating synthetic virions on the (3) layer immediately before the (3) and (1) layers are stacked, or 1) There is a method of laminating synthetic fibers on the layer, and inverting the synthetic fiber on the (3) layer. At this time, for the purpose of bonding the synthetic fiber to the layer (1) or the layer (3), water spray or a binder can be used.

In this study, it is necessary for these four layers to be stacked in the order described above ^), but after overlapping, the ends are bonded with a binder or a heat seal to form a paper diaper. Become. Also, before or after bonding, pressurize or emboss It is also possible to reduce the thickness of the body.

The weight ratio of these four layers is usually 80 to 99% based on the weight of the disposable diaper, because the weight of the (2) layer and the (3) layer increases. The weight ratio of the (2) layer and the (3) layer is usually such that the weight of the (2) is in the range of 10 to 50% in comparison with the weight of the (3), and if the weight is less than 10%, the dry-tatch property is improved. However, if it exceeds 50%, the ability to absorb urine becomes insufficient. More preferably, it is 15-40%.

BRIEF DESCRIPTION OF THE FIGURES

Next, the disposable paper diaper of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a disposable disposable diaper of the present invention. Numeral 1 is a liquid-permeable exterior material that comes into contact with the wearer's skin, and is usually a nonwoven fabric having a basis weight of 10 to 20 g / m 'and a thickness of 0.05 to 1 mm. This layer is a layer of synthetic fibers, and usually a tube having a basis weight of 30 to 100 g nonf and a density of 0.05 gΖ3 is used. Numeral 3 is an absorbent layer, which preferably comprises floc pulp and superabsorbent polymer 5. Normally 100% to 300 g for cotton wool pulp and 60 to 200 g for water-absorbing polymer

/ m 'basis weight and the superabsorbent polymer is dispersed in the flocculent valve. Reference numeral 6 denotes a liquid-impermeable exterior material, usually called a back sheet, which is generally made of a polyethylene film, and is a 71¾-heat sealed portion.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in more detail with reference to Examples.

Example 1

A nonwoven fabric made of rayon with a basis weight of 20 g Zm 'is used as the liquid-permeable exterior material layer (1), and a polyester fiber (EI DuPont) is used as the synthetic fiber layer (2). ) Was used as the absorbent layer (3), using a tube with a basis weight of 50 g / nf formed by carding. Using a laminate obtained by blending 100 g / Lp with 100 g / πί of super-absorbent polymer (Sanetsu IM-1000, manufactured by Sanyo Kasei Kogyo) in a stacking fiber device Meanwhile, a polyethylene film having a basis weight of 20 g / πί was used as the liquid-impermeable exterior material layer (6). These four layers were successively superimposed, cut into a size of 20 cm × 50 cm, and embossed at 30 ° 04, 80′C to obtain a disposable disposable diaper (I). Examples 2 to 4

The disposable disposable diapers (H), (Μ) and (（) were prepared in the same manner as in Example 1 except that the basis weight of the synthetic fiber web in Example 1 was changed to 30 g m ', 50 g m nf, and 150 g / πί. IV) was obtained.

Example 5, '6

Disposable disposable diapers (V) and (VI) were obtained in the same manner as in Example 1 except that the synthetic fiber web in Example 1 was changed to Polypropylene web or polyester cloth.

Example 7

A disposable disposable diaper (W) was prepared in the same manner as in Example 1 except that the absorbent layer in Example 1 was changed from 100 g nf of Sanette IM-1000 to granules on 100 g of cotton-like pulp. Was obtained.

Comparative Examples 1 to 4

The procedure was the same as in Example 1 except that the synthetic fiber web in Example 1 was changed to .0 gm ', 10 g / rrf or 18 gZm', or to 50 g rayon fiber. The disposable disposable diapers (i) (ϋ), (iii) and (iv) were obtained.

Test example 1

Performance tests were performed on the disposable disposable diapers obtained in Examples 1 to 7 and Comparative Examples 1 to 4. The test results are shown in Table-1. What The test method is as follows.

(1) Dryer touch

Place the above disposable paper diaper horizontally, inject 50 ml of 1% saline 3 times every 30 minutes into the center and leave it for 30 minutes, then leave 20 sheets of filter paper in the center

(100 cni), and then put a load of 4 kg on it, leave it for 10 minutes, measure the weight increase of the filter paper, and use this value as an index of the dryness. The smaller the value is, the better the dry touch property is.

(2) Absorption amount ''

Place the above disposable diaper horizontally, bend one end (length direction) 5 cm into a 45 ° slope, inject 1% saline into the center of the line at a speed of 20 ml, and then dispose the disposable diaper. Injection was continued until leakage occurred from one end, and the injection amount was used as the absorption amount.

Table 1

(¾) * Sanette marked with * is Sunwet i M-1000

Is shown. As described above, the disposable disposable diaper of the present invention has improved liquid absorbing power and liquid retaining power to a sufficiently satisfactory level as compared with conventional ones. In addition, there is less bleeding at the top when pressure is applied to the disposable disposable diaper, and the dry touch is improved. Furthermore, since the liquid is easily diffused to the side, all of the used water-absorbing resin or water-absorbing agent can be used effectively, and there is a characteristic that more urine can be absorbed and retained.

Claims

Scope of claim

1. Liquid-permeable exterior material layer (1), 髙 water-absorbing polymer or an absorbent layer (3) composed of 80% or less by weight of absorbent fiber, and non-liquid-permeable exterior material layer (6) )

There is a cotton bud rose layer (2) having a thickness of 2 to 10 の間に composed of a synthetic fiber at a ratio of 10 to 50% by weight based on the weight of the layer (3) between the layers (1) and (3). A disposable disposable diaper having improved dry touch characteristics.

2. The disposable diaper according to claim 1, wherein the cotton-like rose layer (2) made of synthetic fibers has a water absorption of 10% or less of its own weight.

3. Synthetic fibers with hydrophobic polyolefins, polyads, polyesters, polyacrylonitrile, polyvinyl chloride, vinylidene chloride, polyurethane, polyethylene 3. The disposable diaper according to claim 1 or 2, wherein the disposable diaper is a refillable polyethylene.

4. Consists of a liquid-permeable exterior material layer (1), an absorbent layer (3) made of highly water-absorbing polymer or 80% by weight or less absorbent fiber, and a non-liquid-permeable exterior material layer (6). In addition to the absorbent composite, between (1) layer and (3) layer, 10 to 50% by weight based on the weight of the (3) layer, and an opened thickness of 2 to 10% synthetic fiber cotton A method for producing a disposable disposable diaper having improved ditchability, characterized by forming a lumpy layer (2).

5. The synthetic fiber cotton lumps are laminated on the (1) layer or the (3) layer, and then the (3) layer or the (1) layer is laminated to form the (2) layer. 4. The production method according to item 4.

6. Liquid-permeable exterior material layer (1), absorbent layer made of super absorbent polymer or absorbent fiber of 80% by weight or less (3), and non-permeable In forming the absorbent composite composed of the aqueous exterior material layer (6), the ratio of the layer (1) and the layer (3) can be easily reduced to 10 to 50% by weight based on the weight of the layer (3). A method for improving the dry touch property of a disposable disposable diaper, which is characterized by forming an opened synthetic fiber cotton rose layer (2) having a thickness of 2 to 10%.