Absorbent articles for body fluids

Abstract

Provided are a body fluid absorbent article that absorbs body fluids that seep onto a surface material in a spot-like manner and a body fluid absorbent article whose surface material is not easily damaged during use. The body fluid absorbent article comprises a surface material (1), an absorbent body (3), and a leak-proof material (4) arranged in order from the body fluid seepage side. The surface material (1) is composed of a non-woven fabric having cotton fibers as constituent fibers and the cotton fibers interwoven with each other. The non-woven fabric is provided with an oil containing lipophilic monostearate glyceryl and polyoxyethylene lauryl ether, an oil containing stearic acid amide and hardened beef tallow, or an oil containing stearic acid amide and palm oil. The non-woven fabric is provided with cationic starch. The oil content is 0.05 to 1.5 weight % relative to the weight of the non-woven fabric. The cationic starch content is 3 to 5 weight % relative to the weight of the non-woven fabric. A fluffy non-woven fabric (2) is inserted between the surface material (1) and the absorbent body (3). The absorbent body (3) is composed of an aggregate of pulp fibers. The leak-proof material (4) is composed of a synthetic resin film.

Description

Technical Field

[0001] The present invention relates to body fluid absorbent articles such as sanitary napkins and disposable diapers. Background Art

[0002] Absorbent articles for bodily fluids, such as sanitary napkins, are constructed by sequentially placing a surface material, an absorbent body, and a leak-proof material from the side where bodily fluids leak out. Because the surface material comes into direct contact with the skin, a nonwoven fabric composed of cellulose fibers such as cotton, which provide a pleasant feel, is used. To achieve a nonwoven fabric with a more pleasant feel, the applicants of the present invention proposed a soft nonwoven fabric in which stearic acid amide is added to the nonwoven fabric (Patent Document 1).

[0003] Patent Document 1: Japanese Patent No. 5657916 Summary of the Invention

[0004] The present invention is an improvement of the invention of Patent Document 1, and a first object of the present invention is to provide a body fluid absorbent article capable of absorbing body fluids exuded from a surface material in a spot-like manner.

[0005] A second object is to provide a bodily fluid absorbent article that can absorb bodily fluid exuded from a surface material in a spot-like manner and has a surface material that is excellent in abrasion resistance and is not easily damaged during use.

[0006] The present invention solves the first problem by applying a specific oil to the surface material. Specifically, the present invention relates to a bodily fluid absorbent article comprising, in order from the bodily fluid exudate side, a surface material 1, an absorbent body 3, and a leakage-proof material 4. The surface material 1 is characterized in that an oil is applied to a nonwoven fabric composed of interwoven cellulose fibers as constituent fibers, and the oil is selected from the group consisting of an oil containing lipophilic monostearate glyceryl and polyoxyethylene lauryl ether, an oil containing stearic acid amide and hardened beef tallow, and an oil containing stearic acid amide and palm oil.

[0007] The present invention also solves the second problem by pre-applying cationic starch and a specific oil to the surface material. Specifically, the present invention relates to a bodily fluid absorbent article comprising a surface material 1, an absorbent body 3, and a leakage-proof material 4 arranged in this order from the bodily fluid exudation side. The surface material 1 is characterized in that the cationic starch and the oil are applied to a nonwoven fabric composed of interwoven cellulose fibers as constituent fibers. The oil is selected from the group consisting of an oil containing lipophilic monostearate glyceryl and polyoxyethylene lauryl ether, an oil containing stearic acid amide and hardened beef tallow, and an oil containing stearic acid amide and palm oil.

[0008] The surface material 1 used in the present invention is composed of a nonwoven fabric composed of cellulose fibers. Cellulose fibers can be cotton fibers or rayon fibers. Undefatted cotton is particularly preferred because it easily absorbs exuded body fluids in a spot-like manner due to the cottonseed oil adhering to the surface of the cotton fibers. Rayon fibers are typically short fibers with a fineness of 1 to 10 dtex and a fiber length of 10 to 100 mm, but long fibers can also be used. A small amount of other types of fibers besides cellulose fibers may also be mixed into the nonwoven fabric.

[0009] The constituent fibers composed of cellulose fibers are interwoven with each other. As a result, the constituent fibers are bonded together to form a nonwoven fabric of a predetermined strength. Therefore, an adhesive is not required to bond the constituent fibers together, but it is preferred to additionally bond the constituent fibers with cationic starch to form a nonwoven fabric with higher strength and excellent wear resistance. As a method for interweaving, a water flow interweaving method is preferred. The unit weight of the nonwoven fabric used in the present invention is 10 to 50 g / m 2 about.

[0010] The nonwoven fabric used in the present invention is treated with a specific oil. The specific oil can be a mixture of lipophilic monostearate glyceryl and polyoxyethylene lauryl ether, stearic acid amide and hardened tallow, or stearic acid amide and palm oil. This specific oil imparts both hydrophilicity and water repellency, allowing for the targeted absorption of exuded body fluids. The ratio of lipophilic monostearate to polyoxyethylene lauryl ether, the ratio of stearic acid amide to hardened tallow, and the ratio of stearic acid amide to palm oil in the oil are preferably equal.

[0011] To apply an oil to the nonwoven fabric used in the present invention, the oil is typically applied in a liquid state. In the case of lipophilic monostearate and polyoxyethylene lauryl ether, since polyoxyethylene lauryl ether is a liquid, lipophilic monostearate can be dissolved or dispersed therein and applied to the nonwoven fabric. Alternatively, stearic acid amide and hardened tallow can be dissolved in a solvent such as acetic acid and applied to the nonwoven fabric. Furthermore, when using a cationized starch and an oil, a mixture of the oil dissolved or dispersed in a cationized starch paste can be applied to the nonwoven fabric.

[0012] The amount of oil applied is optional, but is generally preferably 0.05 to 1.5% by weight relative to the weight of the nonwoven fabric. If the amount is less than 0.05% by weight, the nonwoven fabric tends to be less susceptible to spot absorption of body fluids. If the amount exceeds 1.5% by weight, the tensile strength (strength) of the nonwoven fabric tends to decrease.

[0013] As mentioned above, cationic starch is a substance used to bond the constituent fibers to each other. Since cationic starch easily adheres to cellulose fibers, it can increase the strength of non-woven fabrics. Starch has a molecular weight ranging from thousands to hundreds of millions, but in the present invention, it is preferred to use starches in the thousands to hundreds of thousands. If starch with a molecular weight of tens of millions is used, the paste becomes highly viscous, making it difficult to impart to the non-woven fabric. Specifically, wheat starch, potato starch, corn starch, corn starch containing high amylose, tapioca starch, rice starch, taro starch, etc. can be used. As a cationizing agent for cationizing these starches, conventionally known diethylaminoethyl chloride, 3-chloro-2-hydroxypropyltrimethylammonium chloride, 2,3-epoxypropyltrimethylammonium chloride, etc. can be used.

[0014] The amount of cationic starch added is optional, but is generally preferably 3 to 5% by weight relative to the weight of the nonwoven fabric. If the amount is less than 3% by weight, abrasion resistance tends to decrease. If the amount exceeds 5% by weight, the feel and softness of the nonwoven fabric tend to decrease.

[0015] The body fluid absorbent article of the present invention is formed by arranging an absorbent body 3 under a surface material 1. The absorbent body 3 is an aggregate mainly composed of pulp fibers. In the present invention, a fluffy nonwoven fabric 2 having cushioning properties can be arranged between the surface material 1 and the absorbent body 3. By arranging the fluffy nonwoven fabric 2, the skin contact of the surface material 1 is further improved. The fluffy nonwoven fabric 2 is thicker than the nonwoven fabric constituting the surface material 1. In addition, the constituent fibers of the fluffy nonwoven fabric 2 are preferably hydrophobic fibers other than cellulose fibers. This is because if hydrophilic fibers such as cellulose fibers are used, the point absorbency of the surface material 1 will be suppressed.

[0016] A leak-proof material 4 is disposed beneath the absorbent body 3. A synthetic resin film impermeable to bodily fluids, for example, can be used as the leak-proof material 4. A fastener (not shown) such as double-sided adhesive tape may be disposed on the surface of the leak-proof material 4 (the side opposite the skin). This fastener secures the bodily fluid absorbent article to the undergarment to prevent it from shifting during use.

[0017] The body fluid absorbent article of the present invention can be used as a sanitary napkin or a disposable diaper. In addition, it can also be used as a wound patch for absorbing blood oozing from a wound.

[0018] The absorbent article of the present invention utilizes a surface material imparted with a specific oil agent, thereby achieving the effect of spot-absorbing exuded body fluids. Furthermore, the surface material imparted with a specific oil agent and cationic starch achieves the effect of spot-absorbing exuded body fluids while being less susceptible to damage. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic cross-sectional view of a bodily fluid absorbent article according to an example of the present invention.

[0020] Explanation of symbols

[0021] 1. Surface material

[0022] 2 fluffy non-woven fabric

[0023] 3 Absorber

[0024] 4. Leak-proof materials DETAILED DESCRIPTION

[0025] Example

[0026] Example 1

[0027] [Preparation of non-woven fabric]

[0028] Bleached cotton (manufactured by Marusan Industry Co., Ltd.) with 0.4 wt% of natural oil (cottonseed oil) was prepared. The bleached cotton was opened and gathered by an air-laid carding machine to obtain a weight per unit area of ​​about 30 g / m 2 The fiber web is placed on a support made of a 90-mesh plastic fabric and is water-entangled while being transported. The water-entanglement is carried out using a spray device with a nozzle diameter of 0.1 mm and spray holes arranged in a row with a hole interval of 0.6 mm, and the following method is used. That is, after water is sprayed twice from the spray device at a spray pressure of 5.5 MPa on the surface of the fiber web, water is sprayed twice at a spray pressure of 5.5 MPa on the back of the fiber web to obtain a fiber pile. The fiber pile is placed on a support made of a 10-mesh plastic fabric and is further water-entangled while being transported. This water treatment is carried out using the above-mentioned spray device and water is sprayed twice at a spray pressure of 5.5 MPa to obtain a non-woven fabric.

[0029] [Preparation of oil]

[0030] An oil solution containing lipophilic monostearate glyceryl and polyoxyethylene lauryl ether is prepared.

[0031] [Manufacturing of surface materials]

[0032] The above-mentioned oil was applied to the non-woven fabric using a kiss coater. The amount of the oil applied was 0.3% by weight relative to the weight of the non-woven fabric. After applying the oil, the non-woven fabric was dried at 130°C to obtain a weight per unit area of ​​30 g / m 2 surface material.

[0033] Example 2

[0034] A surface material was obtained by the same method as in Example 1, except that an oil solution prepared by dissolving stearic acid amide and hardened beef tallow in acetic acid was applied instead of the oil solution used in Example 1. The amount of the oil solution composed of stearic acid amide and hardened beef tallow applied was 0.1% by weight relative to the weight of the nonwoven fabric.

[0035] Example 3

[0036] [Preparation of non-woven fabric]

[0037] Bleached cotton (manufactured by Marusan Industry Co., Ltd.) with 0.4 wt% of natural oil (cottonseed oil) was prepared. The bleached cotton was opened and gathered by an air-laid carding machine to obtain a weight per unit area of ​​about 35 g / m 2 A fiber web was placed on a mesh support and water-entangled while being transported. Water-entanglement was performed using a spray device with nozzles having a nozzle diameter of 0.1 mm and holes arranged in a row at intervals of 0.6 mm, using the following method. Specifically, the fiber web was placed on a 100-mesh support, and water was sprayed twice from the spray device at a pressure of 2.8 MPa onto the surface of the fiber web. The fiber web was then turned over and water was sprayed twice at a pressure of 2.8 MPa onto the back of the fiber web to produce a fiber fleece. This fiber fleece was placed on a 25-mesh support and water was sprayed twice at a pressure of 4.1 MPa using the aforementioned spray device to produce a nonwoven fabric.

[0038] [Preparation of oil]

[0039] An oil formulation containing stearamide and palm oil was prepared.

[0040] [Manufacturing of surface materials]

[0041] The oil was applied to the nonwoven fabric by spraying and then dried at 100° C. to obtain a surface material to which 0.3% by weight of the oil was applied based on the weight of the nonwoven fabric.

[0042] Example 4

[0043] A surface material was obtained by the same method as in Example 3 except that the amount of the oil agent applied was 0.5% by weight relative to the weight of the nonwoven fabric.

[0044] Example 5

[0045] A surface material was obtained by the same method as in Example 3 except that the amount of the oil agent applied was 0.7 wt % based on the weight of the nonwoven fabric.

[0046] Comparative Example 1

[0047] The nonwoven fabric obtained in Example 3 was sprayed with a paste of pregelatinized starch (starch with a molecular weight of several hundred thousand) and then dried at 100° C. to obtain a surface material having 3% by weight of pregelatinized starch relative to the weight of the nonwoven fabric.

[0048] Comparative Example 2

[0049] The nonwoven fabric obtained in Example 3 was coated with a liquid containing a paper strengthening agent mainly composed of polyacrylic acid (salt) by spraying, and then dried at 100° C. to obtain a surface material to which 3% by weight of the paper strengthening agent was applied based on the weight of the nonwoven fabric.

[0050] The surface materials obtained in Examples 1 to 5 and Comparative Examples 1 and 2 were evaluated for point absorbency (mm) by the following method. The results are shown in Table 1.

[0051] [Evaluation of point absorbency (mm)]

[0052] Take three 10 cm x 10 cm test pieces from each surface material obtained in Examples 1 to 5 and Comparative Examples 1 and 2. Overlap the three test pieces and place them on filter paper. Add 1 cc of blue solution dropwise to the test pieces and let them sit for 5 minutes. Then, remove only the top test piece (the one directly in contact with the blue solution) and calculate the sum of the widest longitudinal length (mm) and widest lateral length (mm) of the blue-colored area to determine the point absorbency (mm).

[0053] [Table 1]

[0054]

[0055] From the results in Table 1, it can be seen that the surface materials of Examples 1 to 5 are superior to the surface materials of Comparative Examples 1 and 2 in point absorptivity.

[0056] Example 6

[0057] [Preparation of mixed solution]

[0058] An oil containing stearamide and palm oil was added and mixed into a paste of cationic starch (starch with a molecular weight of several hundred thousand) to obtain a mixed solution. The weight ratio of the cationic starch to the oil in the mixed solution was 6:1.

[0059] A surface material containing 3 wt % of cationic starch and 0.5 wt % of oil relative to the weight of the nonwoven fabric was obtained by the same method as in Example 3 except that this mixed liquid was used instead of the oil in Example 3.

[0060] Example 7

[0061] A surface material containing 3 wt % of cationized starch and 1.0 wt % of oil relative to the weight of the nonwoven fabric was obtained by the same method as in Example 6 except that a mixture of cationized starch and oil was used at a weight ratio of 3:1.

[0062] Example 8

[0063] A surface material containing 3% by weight of cationic starch and 0.5% by weight of the oil relative to the weight of the nonwoven fabric was obtained by the same method as in Example 6, except that an oil containing lipophilic monostearate glyceryl and polyoxyethylene lauryl ether was used instead of the oil containing stearic acid amide and palm oil.

[0064] Example 9

[0065] A surface material containing 3% by weight of cationic starch and 1.0% by weight of the oil relative to the weight of the nonwoven fabric was obtained by the same method as in Example 7, except that an oil containing lipophilic monostearate glyceryl and polyoxyethylene lauryl ether was used instead of the oil containing stearic acid amide and palm oil.

[0066] Example 10

[0067] A surface material having 3% by weight of cationic starch and 0.5% by weight of an oil agent relative to the weight of the nonwoven fabric was obtained by the same method as in Example 6, except that a cationic starch (starch with a molecular weight of tens of thousands) paste was used instead of a cationic starch (starch with a molecular weight of hundreds of thousands).

[0068] Example 11

[0069] A surface material having 3% by weight of cationic starch and 1.0% by weight of an oil agent relative to the weight of the nonwoven fabric was obtained by the same method as in Example 7, except that a cationic starch (starch with a molecular weight of tens of thousands) paste was used instead of a cationic starch (starch with a molecular weight of hundreds of thousands).

[0070] Example 12

[0071] A surface material containing 5 wt % of cationized starch and 0.5 wt % of oil relative to the weight of the nonwoven fabric was obtained by the same method as in Example 10 except that a mixture of cationized starch and oil was used at a weight ratio of 10:1.

[0072] Example 13

[0073] A surface material having 5% by weight of cationized starch and 1% by weight of oil added to the weight of the nonwoven fabric was obtained by the same method as in Example 10 except that a mixture of cationized starch and oil was used at a weight ratio of 5:1.

[0074] Example 14

[0075] A surface material having 5% by weight of cationized starch and 0.5% by weight of an oil agent relative to the weight of the nonwoven fabric was obtained by the same method as in Example 12, except that a cationized starch (starch with a molecular weight of several thousand) paste was used instead of a cationized starch (starch with a molecular weight of several tens of thousands).

[0076] Example 15

[0077] [Preparation of mixed solution]

[0078] An oil containing stearamide and palm oil was added to a paste of cationic starch (starch with a molecular weight of several thousand) and mixed to obtain a mixed solution. The weight ratio of the cationic starch to the oil in the mixed solution was 50:7.

[0079] A surface material to which 5% by weight of cationic starch and 0.7% by weight of oil agent were applied based on the weight of the nonwoven fabric was obtained by the same method as in Example 6 except that this mixed solution was used instead of the mixed solution of Example 6.

[0080] Example 16

[0081] [Preparation of mixed solution]

[0082] An oil containing stearamide and palm oil is added to a paste of alpha starch (starch with a molecular weight of several hundred thousand) and mixed to form a mixture. The weight ratio of the alpha starch to the oil in the mixture is 10:1.

[0083] A surface material to which 3% by weight of pregelatinized starch and 0.3% by weight of an oil agent were applied based on the weight of the nonwoven fabric was obtained by the same method as in Example 6 except that this mixed solution was used instead of the mixed solution of Example 6.

[0084] Example 17

[0085] A surface material having 3% by weight of cationized starch and 0.5% by weight of an oil agent relative to the weight of the nonwoven fabric was obtained by the same method as in Example 10, except that a cationized starch (starch with a molecular weight of several thousand) paste was used instead of a cationized starch (starch with a molecular weight of several tens of thousands).

[0086] Example 18

[0087] [Preparation of mixed solution]

[0088] An oil agent containing stearic acid amide and palm oil was added and mixed into a liquid containing a paper strengthening agent mainly composed of polyacrylic acid (salt) to obtain a mixed liquid. The weight ratio of the paper strengthening agent to the oil agent in the mixed liquid was 10:1.

[0089] A surface material to which 3% by weight of a paper strengthening agent and 0.3% by weight of an oil agent were added based on the weight of the nonwoven fabric was obtained by the same method as in Example 6 except that this mixed solution was used instead of the mixed solution of Example 6.

[0090] Example 19

[0091] [Preparation of mixed solution]

[0092] An oil agent containing stearic acid amide and palm oil was added and mixed into a liquid containing a paper strengthening agent mainly composed of polyacrylic acid (salt) to obtain a mixed liquid. The weight ratio of the paper strengthening agent to the oil agent in the mixed liquid was 30:7.

[0093] A surface material to which 3% by weight of a paper strengthening agent and 0.7% by weight of an oil agent were added based on the weight of the nonwoven fabric was obtained by the same method as in Example 6 except that this mixed solution was used instead of the mixed solution of Example 6.

[0094] Comparative Example 3

[0095] The nonwoven fabric obtained in Example 3 was used as a surface material without any treatment.

[0096] In addition to the above-mentioned point absorption (mm), the surface materials obtained in Examples 6 to 19 and Comparative Example 3 were evaluated for wear resistance (times) by the following method. The results are shown in Table 2.

[0097] [Evaluation of wear resistance (times)]

[0098] From each surface material obtained in Examples 6 to 19 and Comparative Example 3, 30 samples with a length of 293 mm and a width of 165 mm were taken in random directions. The 6-point sample was set in a Gakushin type friction fastness tester (manufactured by Daiei Kagaku Seiki Mfg. Co., Ltd., model "RT-300") in accordance with JIS L 0849 to measure the wear resistance. When setting the sample, a polyurethane pad was pre-laid under the sample, and the sample was fixed to the fixing part equipped with the Gakushin type friction fastness tester in a manner that would not produce wrinkles. In addition, the surface of the friction terminal was covered with a cloth adhesive tape, and a load of 300 g was applied to the friction terminal so that the cloth adhesive tape and the sample were in contact. Then, the friction terminal was slid at a reciprocating speed of 30 times / minute, and the number of reciprocating times when all the 6-point samples were visually damaged was measured. This measurement was carried out 5 times, and their average value was taken as the wear resistance (times). Even if the number of reciprocating strokes exceeded 500, if no damage was observed at all 6 points of the sample, the measurement was stopped and the number of reciprocating strokes was set to 500. Therefore, 500 strokes was the maximum value for the wear resistance (times).

[0099] [Table 2]

[0100]

Claims

1. A body fluid absorbent article comprising a surface material, an absorbent body, and a leakage-proof material arranged in this order from the body fluid exudation side, characterized in that: The surface material is formed by adding cationic starch and an oil agent to a non-woven fabric composed of cellulose fibers as constituent fibers and interwoven with the constituent fibers, and the oil agent is selected from the following oil agents: Contains lipophilic monostearate glyceryl and polyoxyethylene lauryl ether oil, An oil containing stearamide and hardened tallow, and an oil containing stearamide and palm oil; The amount of cationic starch added is 3 to 5% by weight relative to the weight of the non-woven fabric. The amount of the oil agent applied is 0.05 to 1.5 wt % relative to the weight of the nonwoven fabric.

2. The body fluid absorbent article according to claim 1, wherein The cellulose fiber is cotton fiber.

3. The bodily fluid absorbent article according to claim 1, wherein a bulky nonwoven fabric having cushioning properties is disposed between the surface material and the absorbent body.

4. The body fluid absorbent article according to claim 1, wherein The absorbent body is an aggregate of pulp fibers.

5. The body fluid absorbent article according to claim 1, wherein The bodily fluid absorbent article is a disposable diaper.

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