Absorbent sanitary articles containing skincare compositions

Abstract

This disclosure relates to an absorbent sanitary article comprising a liquid-permeable top sheet and an absorbent core, wherein the top sheet is provided with a skincare composition on at least the side of the top sheet facing the user when the absorbent sanitary article is worn by the user. The skincare composition is a dry coating comprising gluconic acid and a water-miscible medium, such as glycerin, propylene glycol and / or PEG. The absorbent sanitary article may be a diaper, incontinence shield, sanitary napkin, panty liner, tampon or wound dressing.

Description

[Technical Field]

[0001] This disclosure relates to an absorbent sanitary article comprising a fluid-permeable top sheet and an absorbent, wherein when the absorbent sanitary article is worn by a user, a skincare composition is provided to at least the side of the fluid-permeable top sheet facing the user. [Background technology]

[0002] The types of absorbent sanitary articles relating to this disclosure, such as diapers for children and adults, incontinence shields, sanitary napkins and panty liners, tampons, or wound dressings, are adapted to be worn against the user's skin for the purpose of absorbing body exudates, such as urine, feces, drainage, physiological fluids, or wound exudates, which may include fluids leaked from blood vessels, and may contain serum, fibrin, and leukocytes. Such absorbent sanitary articles conventionally include a liquid-permeable top sheet layer, an absorbent core, and a back sheet layer.

[0003] The use of products applied to come into direct contact with the skin can result in undesirable side effects. These can arise due to factors related to enclosed conditions, humidity, machinery, microorganisms, and enzymes, all of which interact to varying degrees and amplify each other's effects, potentially causing different forms of skin irritation and primary and secondary skin infections that may occur occasionally during the use of such articles. An increase in pH is a normal phenomenon, for example, during the use of physiological articles that come into contact with the skin. It has been demonstrated that skin with a pH below 5.0 is in better condition than skin with a pH above 5.0. This has been shown by measuring physiological and physical parameters of barrier function, hydration, and scaling. The effect of pH on the adhesion of the resident skin microbiota has also been evaluated, showing that acidic skin pH (4-4.5) retains the resident bacterial flora attached to the skin, while alkaline pH (8-9) promotes its dispersion from the skin. For example, see Lambers H et al (2006), Natural Skin surface pH is on average below 5, which is beneficial for its resident flora. Int J Cosmet Sci, 28(5), 359-70.

[0004] Another example of an undesirable effect of using absorbent sanitary products that come into contact with the skin is the increased activity of enzymes exhibiting strong pH-dependent activity, such as lipases and proteases, which rise with increasing pH. With increased enzyme activity, the skin begins to break down, becoming more sensitive to mechanical forces and bacterial attacks.

[0005] Absorbent sanitary articles containing acidifying agents incorporated to control the pH of skin in contact with the absorbent article are generally known in the art. The acidifying agent may be provided in the form of a lotion or aqueous solution.

[0006] The application of aqueous acidifying agents may not significantly affect the absorbency of absorbent sanitary materials. However, other aspects should be considered, such as the efficacy of adding the agent during use of the absorbent sanitary material, the simple and well-functioning application process, and ensuring a long shelf life, i.e., storage stability. [Overview of the project] [Problems that the invention aims to solve]

[0007] Therefore, in this field, there is still a need for improved absorbent sanitary articles with enhanced skincare properties. [Means for solving the problem]

[0008] This disclosure relates to an absorbent sanitary article having improved skincare properties. The absorbent sanitary article comprises a top sheet provided with a skincare composition, which is intended to transfer to the user's skin tissue or mucous membranes during use.

[0009] In one embodiment, the disclosure relates to an absorbent sanitary article comprising a liquid-permeable top sheet and an absorbent core, wherein the top sheet is provided with a skincare composition on at least the side of the top sheet facing away from the absorbent core. The skincare composition is a dry coating comprising gluconic acid and a water-miscible medium, such as glycerin, propylene glycol and / or PEG.

[0010] In one embodiment, the disclosure relates to an absorbent sanitary article comprising a liquid-permeable top sheet, a back sheet, and an absorbent core disposed between the top sheet and the back sheet, wherein the top sheet is provided with a skincare composition on at least the side of the top sheet facing away from the absorbent core. The skincare composition is a dry coating comprising gluconic acid and a water-miscible medium, such as glycerin, propylene glycol, and / or PEG.

[0011] In one embodiment, the disclosure relates to an absorbent sanitary article, wherein the liquid-permeable top sheet and absorbent core are an integrated structure comprising either a laminate or a single layer having both liquid-permeable and liquid-absorbent functions.

[0012] In the presence of water, lactones exist in equilibrium between their lactone form and their corresponding hydroxycarboxylic acid form, thereby providing a pH-adjusting effect. Hereafter, the term "gluconic acid" refers to the equilibrium system between gluconic acid and its corresponding lactone. This equilibrium system between gluconic acid and its corresponding lactone can be obtained by either mixing gluconic acid or gluconolactone in water, or by mixing both gluconic acid and gluconolactone in water.

[0013] The water-miscible media in the skincare composition, such as glycerin, propylene glycol, and / or PEG, is measured over the area to be coated at a concentration of 0.04 to 9.0 g / m². 2 It may be provided on the top sheet in quantities within the range of [amount].

[0014] The amount of gluconic acid measured across the coated area was 0.01–4.0 g / m². 2 It may be provided on the top sheet in quantities within the range of [amount].

[0015] Dry coatings are measured over the coated area and have a viscosity of 0.2–10.0 g / m². 2 Within this range, optionally 0.2 to 5.0 g / m 2 It may be provided on the top sheet in quantities within the range of [amount].

[0016] In one embodiment, the water-miscible medium is glycerin. In the application of the skincare composition to the user's skin, a high weight percent of glycerin in the dry coating may have a moisturizing effect on the user. As a result of its moisturizing properties, glycerin counteracts the negative effects that arise in connection with dehydration of skin tissue and mucous membranes.

[0017] Furthermore, it has been found that the transfer of gluconic acid to the user's skin is significantly higher in skincare compositions containing glycerin compared to those containing gluconic acid but without glycerin. Improved gluconic acid transfer to the skin is also beneficial because it more effectively lowers pH. This is beneficial for various absorbent hygiene products aimed at maintaining or improving a diverse and healthy skin microbiome.

[0018] The water activity value of the dry coating may be less than 0.7 or optionally less than 0.6. Because the water activity of the dry coating is low, microbial growth may be suppressed.

[0019] Skincare compositions do not need to contain preservatives. For skincare compositions that do not contain water-miscible media, such as glycerin, propylene glycol, and / or PEG, the water activity may be higher and need to be protected if they must be stored stably before being applied to the top sheet layer and dried. Preservatives are also known to reduce the activity of beneficial skin bacteria and can adversely affect the diversity and richness of the skin microbiome. Therefore, skincare compositions that do not contain preservatives are beneficial. Examples of preservatives include sodium benzoate, potassium sorbate, phenoxyethanol, chlorphenesin, and dehydroacetic acid.

[0020] Gluconic acid can be obtained from the group consisting of γ- and / or δ-lactones. Dry coatings containing gluconic acid on the top sheet have been shown to maintain a low pH and be more stable than the corresponding dry coating of lactic acid.

[0021] In another aspect, the present disclosure relates to a method for manufacturing an absorbent hygiene product that includes disposing an absorbent core between a liquid-permeable topsheet and a backsheet, wherein the topsheet is provided with a skin care composition on at least the side of the topsheet facing away from the absorbent core. The skin care composition is a dry coating that includes gluconic acid and a water-miscible medium such as glycerin, propylene glycol, and / or PEG.

[0022] In yet another aspect, the present disclosure relates to the use of an absorbent hygiene product for adjusting or maintaining the pH of the skin in contact with the product to a value between 3.5 and 5.5.

[0023] These and other aspects of the invention are further described below.

Best Mode for Carrying Out the Invention

[0024] In a first aspect, the present disclosure relates to an absorbent hygiene product that includes a liquid-permeable topsheet, a backsheet, and an absorbent core disposed between the topsheet and the backsheet. The product defines a side facing the body intended to be disposed against or towards the skin of the wearer and a side facing the opposite clothing side, and the topsheet is the outermost layer on the side facing the body. According to one embodiment, the absorbent hygiene product is a thin absorbent liner that includes a liquid-permeable topsheet and a backsheet but does not include a separate absorbent core layer. According to this embodiment, the liquid-permeable topsheet functions as both the topsheet and the absorbent core.

[0025] In the product, the topsheet is provided with a skin care composition on at least the side of the topsheet facing away from the absorbent core, which is the side facing the user when the user wears the absorbent hygiene product. The skin care composition is a dry coating that includes a water-miscible medium such as glycerin, propylene glycol, and / or PEG and further includes gluconic acid. <0​As used herein, the term “dry coating” refers to a coating formed on a web material by applying a composition to the web material in a liquid carrier that is liquid at room temperature, such as an aqueous solution, and then drying the web material as a result of the dry coating being formed on the web material. When referred to herein, “dry” coatings have a water content that does not significantly exceed the level of water that is unavoidable due to the balance between the coating and the surrounding atmosphere.

[0027] When the skincare composition is provided to the top sheet material, it is at least on the side of the top sheet facing away from the absorbent core, i.e., the side of the top sheet facing the wearer. The skincare composition may also be provided on the side of the top sheet facing the absorbent core, i.e., the side of the top sheet facing the garment. If the top sheet material is a fibrous material, such as a nonwoven fabric, the dry coating can essentially be a layer around at least a portion of the circumference of the individual fibers.

[0028] Gluconic acid can be obtained from the group consisting of γ- and δ-lactones, i.e., lactones having a 5 or 6-membered ring. The function of gluconic acid in dry coatings according to this disclosure is to maintain or adjust the pH to a beneficial value, and therefore beneficial for the health of the skin in the delicate area. This can be achieved by using absorbent sanitary articles according to this disclosure, because the gluconic acid is coated on a top sheet, which is a material layer in direct contact with the user's skin, and therefore can contribute to a favorable pH on the top sheet.

[0029] In the presence of water, lactones exist in equilibrium between their lactone form and their corresponding hydroxycarboxylic acid form, thereby providing a pH-adjusting effect. Hereafter, the term "gluconic acid" refers to the equilibrium system between gluconic acid and its corresponding lactone. This equilibrium system between gluconic acid and its corresponding lactone can be obtained by either mixing gluconic acid or gluconolactone in water, or by mixing both gluconic acid and gluconolactone in water.

[0030] The migration of lactones or their corresponding hydroxycarboxylic acids is thought to occur both as dry migration from the coating in contact with the skin and as wet migration by bodily fluids in contact with the environment between the coating, the skin, the top sheet, and the user's skin.

[0031] The term gluconic acid refers to an equilibrium system of lactone ring and hydroxycarbone compounds. For the purposes of this disclosure, while lactones may exist in different stereoisomers, this term is considered to encompass all isomers of lactones. The lactone currently preferred for use according to the present invention is the gluconolactone formed by intramolecular esterification of gluconic acid, specifically D-glucono-δ-lactone. At least one lactone may therefore be or largely comprise a gluconolactone, e.g., D-glucono-δ-lactone.

[0032] In addition to a water-miscible medium and gluconic acid, the dry coating composition may further contain a surfactant. The surfactant according to this disclosure is a substance that reduces the surface tension and / or interfacial tension with other phases of the medium in which it is dissolved, and is therefore actively adsorbed in liquid / solid and / or other interfaces. The surfactant may be any known surfactant suitable for use in sanitary applications, as is generally known in the art, and suitable surfactants may include any cationic surfactant, anionic surfactant, nonionic surfactant, amphoteric surfactant or amino acid-type surfactant suitable for use in sanitary applications, which should reduce the surface tension of the aqueous solution so as to allow the solution to spread more easily on the top sheet. This is particularly suitable for top sheet materials containing a large amount of synthetic fibers or composed entirely of synthetic fibers, and is therefore primarily hydrophobic. Hydrophobic top sheet materials may also be preferred due to the reduction of the wet zone after the top sheet is wetted.

[0033] Examples of suitable surfactants include Silastol PHP26, Silastol PHP 28, Silastol PHP 163, Silastol PHP 207 (Schill & Seilacher GmbH), Stantex S 6327 (Cognis), Duron OS 1547, Duron OF 4012 (CHT / BEZEMA), and Nuwet 237. * And Nuwet 550 (Momentive).

[0034] The surfactant may be added to the top sheet in a concentration sufficient to exhibit the desired effect, and may be, for example, up to 1 wt%, or for example, 0.1 to 0.8 wt%, based on the weight of the top sheet before treatment, i.e., before application of the dry coating.

[0035] Skincare compositions do not need to contain oils and emulsifiers.

[0036] The dry coating may be applied essentially uniformly to the top sheet, or it may be applied in such a way that it creates a pattern that covers only a portion of the surface of the layer to which it is applied.

[0037] When applied in a patterned manner, the dry coating may cover, for example, at least 10% of the area of ​​the layer to be coated, e.g., 10–90% of the area. For example, the dry coating may be applied locally to the portion of the top sheet intended to come into contact with the skin, particularly to obtain the benefits of pH reduction and moisturizing effects in the coating.

[0038] As used herein, the term “absorbent sanitary articles” refers to products intended to be placed against the wearer’s skin to absorb and contain bodily exudates, such as urine, feces, menstrual fluid, or wound exudates, which may include serum, fibrin, and leukocytes. Examples of absorbent sanitary articles include feminine hygiene products, such as sanitary napkins, panty liners, sanitary panties and women’s inserts, diapers and panty-style diapers for infants and incontinence-prone adults, incontinence pads, diaper inserts, and tampons and wound dressings.

[0039] The liquid-permeable topsheet may be any suitable topsheet material known to those skilled in the art, or it may be a fibrous topsheet material consisting of nonwoven materials such as spunbond, meltblown, carded, water-entangled, or wet-laid. Suitable nonwoven materials may consist of natural fibers such as wood pulp or cotton fibers, synthetic thermoplastic fibers such as polyolefins, polyesters, polyamides and blends and combinations thereof, or mixtures of natural and synthetic fibers. The topsheet material may essentially consist of non-absorbent fibers such as synthetic thermoplastic fibers such as polyolefins, polyesters, polyamides and blends and combinations thereof. The synthetic fibers may be single-component fibers, composite fibers or multi-component fibers including polyesters, polyamides and / or polyolefins such as polypropylene and polyethylene. It is assumed that the nonwoven material used as the topsheet according to this disclosure may be a single layer or a multilayer material. The latter examples, including combinations of spunbond and meltblown fibers, are commonly referred to as SMS (spunbond-meltblown-spunbond), SMMS (spunbond-meltblown-meltblown-spunbond), and other multilayer nonwoven materials.

[0040] The top sheet material may alternatively be a perforated plastic film, i.e., a plastic film having multiple openings or holes that allow liquid to pass through the openings from one side of the film to the other. A further example of a top sheet material is a porous foam.

[0041] Suitable materials for the top sheet should be soft, non-irritating to the skin, and impervious to bodily fluids such as urine or menstrual fluids.

[0042] The top sheet is 10, for example 15 to 50, for example 30, for example 25 g / m² 2 It may have a dry basis weight.

[0043] The backsheet may consist of a thin plastic film, such as polyethylene or polypropylene film, or a nonwoven material coated with a liquid-impermeable material that resists the penetration of liquids, or a hydrophobic nonwoven material. Laminates of plastic film and nonwoven material may also be used. The backsheet material is preferably vapor-permeable and breathable, i.e., liquid-impermeable and vapor-permeable, in order to allow liquids to escape from the absorbent structure but still prevent liquids from passing through the backsheet material.

[0044] The absorbent sanitary articles described herein include an absorbent structure, an absorbent core, positioned between a top sheet and a back sheet. The absorbent core may be of any conventional type. Common examples of absorbent materials include cellulose fluff pulp, tissue layers, superabsorbent polymers (so-called superabsorbents), absorbent foam materials, and absorbent nonwoven materials. It is common to combine cellulose fluff pulp with superabsorbents in the absorbent structure. It is also common to have absorbent structures that include layers of different materials having different properties with respect to liquid capture capacity, liquid distribution capacity, and storage capacity. This is known to those skilled in the art and therefore does not need to be described in detail. Thin absorbents common in sanitary articles often include compressed, mixed, or laminated structures of cellulose fluff pulp and superabsorbents. For the purposes of this disclosure, the term “absorbent core” in its broadest sense also includes liquid-retaining structures that hold liquids by capillary action, such as open-cell porous structures, e.g., foams, and high-loft materials of synthetic fibers.

[0045] The absorbent core for use in absorbent products according to this disclosure may contain a superabsorbent polymer, or may not contain a superabsorbent polymer essentially or completely. If a superabsorbent polymer is present, such may be present in an amount of superabsorbent polymer of, for example, 10, for example, 25, for example, 40, 100, for example, 80, for example, 75 wt%, based on the total weight of the absorbent core.

[0046] The size and absorption capacity of the absorbent core can vary to be suitable for different uses, such as sanitary napkins, panty liners, adult incontinence pads and diapers, newborn diapers, and pants-type diapers.

[0047] As is known in the art, the sanitary absorbent article according to the present disclosure may include additional layers in addition to the topsheet, backsheet, and absorbent core. For example, a liquid-permeable and non-absorbent layer, also referred to herein as an "intermediate layer", may be disposed between the absorbent core and the topsheet over at least a portion of the surface of the absorbent core facing the body. The intermediate layer may be a porous fiber layer essentially composed of non-absorbent fibers, such as a non-woven material, and may be referred to as a capture layer. The basis weight of the intermediate layer is at least 20 g / m 2 , for example at least 40 g / m 2 , for example 40 g / m 2 ~150 g / m 2 , for example 40 g / m 2 ~100 g / m 2 and may be.

[0048] The term "non-absorbent fiber" refers to a fiber that does not absorb water to a perceptible degree. Suitable polymers from which non-absorbent fibers can be formed are non-water-absorbent polymers such as polyolefins, polyesters, polyamides, and blends and combinations thereof. The non-absorbent fibers may be single-component fibers, composite fibers, or multi-component fibers including polyolefins, polyesters, polyamides, and blends and combinations thereof.

[0049] The present disclosure also relates to a method for manufacturing an absorbent sanitary article as defined herein. Methods for manufacturing absorbent products in general vary between different types of absorbent products and are generally known to those skilled in the art. Generally, such methods include the step of joining together a liquid-permeable topsheet and an absorbent core, and the topsheet is provided with a dry coating containing gluconic acid, a water-miscible medium such as glycerin, propylene glycol, and / or PEG.

[0050] A top sheet layer with a dry coating can be provided as a liquid-permeable web material by applying a liquid composition containing a water-miscible medium, such as glycerin, propylene glycol and / or PEG, and gluconic acid, to the web material, and then drying the liquid composition applied to the web material to obtain a dry coating on the web material.

[0051] The skincare composition may be applied to the web material by any suitable means, including spraying, slot coating, kiss-roll coating, and / or immersion of the material in a tank containing the coating composition, and by printing the composition onto the web material by contact or non-contact printing methods known to those skilled in the art. The coating may be carried out inline during the assembly of the absorbent sanitary article. Alternatively, the top sheet material may be prepared separately and delivered to the absorbent sanitary article manufacturing plant as ready-to-use rolls. The coating may also be formed by a combination of the above methods.

[0052] If the dry coating includes at least one water-miscible medium and gluconic acid, plus additional components such as surfactants, each component may be added to the web material in a single coating step or in separate steps. For example, the web material may be pre-treated with a surfactant before the application of gluconic acid, or the gluconic acid may be added simultaneously with the surfactant.

[0053] The benefits of absorbent sanitary articles as described herein are explained here with reference to the following non-limiting examples. [Examples]

[0054] Measurement of skincare compositions Table 1 shows the skincare compositions used.

[0055] [Table 1]

[0056] Water activity measurement The water activity of the skincare composition, glycerin, and gluconic acid was measured using an instrument from Aqua Lab, Dew Point Water Activity Meter 4TE, and the measurements were performed at room temperature (22°C).

[0057] The results of the water activity measurement are shown in Tables 2a and 2b.

[0058] [Table 2]

[0059] From the above results, it is clear that skincare compositions containing glycerin have lower water activity than aqueous skincare compositions that do not contain glycerin. Since the water activity of the glycerin-containing skincare compositions was less than 0.6, preservatives are not necessary for glycerin-containing skincare compositions. For glycerin-free skincare compositions, the water activity is higher, and if storage stability is required before application to nonwoven fabrics and drying, preservatives must be added. Preservatives are known to reduce the activity of beneficial skin bacteria and can negatively affect the diversity and richness of the skin microbiome. Therefore, preservative-free skincare compositions are beneficial. Thus, because skincare compositions contain glycerin, a sufficient surface humidity percentage can be ensured while maintaining a low water activity value, and microbial growth can be inhibited to provide a longer shelf life even without preservatives.

[0060] The results in Table 2b show the water activity of gluconic acid, glycerin, and compositions containing both gluconic acid and glycerin.

[0061] [Table 3]

[0062] pH measurement The pH of the skincare composition was measured before roll coating. The pH of the skincare composition was measured using Thermo Scientific's Orion Star A211.

[0063] Table 3 shows the results of pH measurements of the skincare composition.

[0064] [Table 4]

[0065] The above results indicate that skincare compositions containing glycerin have a higher pH than skincare compositions that do not contain glycerin.

[0066] Measurement of nonwoven fabrics containing skincare compositions pH was also measured on the nonwoven material after it had been dried at room temperature. The pH of the nonwoven samples was measured using a Thermo Scientific Orion Star A211 with a planar electrode. A 36 mm diameter nonwoven sample was perforated, folded twice, and 50 μL of 0.9% NaCl was added. Three samples were measured, and the mean values ​​are shown in Table 4.

[0067] [Table 5]

[0068] The results above show that nonwoven fabrics equipped with a skincare composition containing glycerin and nonwoven fabrics equipped with a skincare composition without glycerin have nearly equal pH values.

[0069] Transition to skin measurement Short-term and longer-term skin measurements were performed. The short-term measurement lasted 1 minute, and the longer-term measurement lasted 4 hours. In both measurements, the tests were conducted on the palm side of the arm of four volunteers.

[0070] For the transition to skin measurement, the nonwoven fabric material was roll-coated with two different skincare compositions: a skincare composition containing glycerin (A) and a skincare composition containing water (B).

[0071] Skincare composition (A) containing glycerin and skincare composition (B) containing water were roll-coated on a nonwoven fabric material Berry Global J1704122, 15 on a laboratory scale (K-Lox, Innova Nordic AB, roll 180 / 14). GSM, #81715171. A roll coaster is a small device that uniformly distributes liquid across the entire surface of the nonwoven fabric. All test samples were roll-coated with either skincare composition (A) containing glycerin or skincare composition (B) without glycerin. The skincare composition without glycerin was aqueous.

[0072] After drying at room temperature, the amount of gluconic acid in two different nonwoven materials was quantified using LC-MS / MS. To enable the measurement of gluconic acid from skin to nonwoven or tape strips in the transition to skin measurements (see Table 5 below), nonwoven samples (26 mm diameter) and tape strips (22 mm diameter) were extracted with 0.1% aqueous ammonia, and gluconic acid was separated using an HSS T3 C18 column (Waters). Gradient elution was performed using an Agilent 1290 Infinity II with a 0.1% aqueous formic acid solution to a 0.1% formic acid acetonitrile solution. Elutions were detected by a 6470 triple quadrupole LC-MS / MS and measured in negative mode by electrospray ionization, and data were recorded using Masshunter Workstation Software (Agilent Technologies). Quantification was made possible by the use of a calibration curve and internal standard (gluconic acid-d6). Dilution ratios and sample area were considered.

[0073] The amount of gluconic acid on the nonwoven fabric surface was measured after the skincare composition was applied to the nonwoven fabric and after the drying step. The values ​​in the table are the average values ​​of nine samples (replicas).

[0074] Table 5 shows the amount of gluconic acid in nonwoven fabric materials containing skincare compositions A and B.

[0075] [Table 6]

[0076] The results in Table 5 show that the amount of gluconic acid was lower in the nonwoven fabric containing skincare composition (A) that contained glycerin than in the nonwoven fabric containing skincare composition (B) that did not contain glycerin.

[0077] In short-duration transfer measurements, subjects were exposed to a nonwoven fabric sample for 1 minute while a 1 kg weight was applied to the top of the sample. After removal of the weight and the nonwoven fabric sample, the outermost layer of skin was collected with a tape band, and the amount of gluconic acid was quantified. Three tape strips were measured for each subject. The average amounts of gluconic acid are shown in Table 6.

[0078] [Table 7]

[0079] Table 6 shows the results from gluconic acid transfer measurements in short-term tests. Clearly, the amount of gluconic acid transferred to the skin is much higher with skincare composition A, which contains glycerin, than with skincare composition B, which does not contain glycerin. Therefore, the short-term tests shown in the figures indicate that the combination of glycerin and gluconic acid was preferable.

[0080] Furthermore, despite lower initial levels of gluconic acid in samples containing glycerin and gluconic acid compared to samples containing water and gluconic acid (see Table 5), gluconic acid migration was significantly higher in combination with glycerin.

[0081] In the longer-duration transition test, subjects wore the nonwoven fabric sample for 4 hours. The nonwoven fabric sample measured 5x8cm and was secured with BSN Fixomull adhesive. Subjects were allowed to move around as usual but returned to the laboratory after 4 hours. In this case, skin pH was measured after removal of the nonwoven fabric material. pH was measured from the skin near the area from which the sample had been removed, after removal from the area covered by the sample. pH was also measured as a control (Ref A and Ref B) in an uncovered area immediately adjacent to each covered area to compare with each area covered by the nonwoven fabric sample containing the skincare composition. Ref A was measured near the area covered by the nonwoven fabric containing glycerin and gluconic acid, and Ref B was measured near the area covered by the nonwoven fabric containing water and gluconic acid. The results of the skin pH measurements are shown below in Table 7.

[0082] [Table 8]

[0083] In the longer transition to skin measurements, as can be seen in Table 7, it was concluded that skin pH decreased more efficiently after wearing nonwoven fabric samples containing glycerin and gluconic acid than after wearing nonwoven fabric samples containing aqueous compositions containing gluconic acid but not glycerin.

[0084] Bacterial growth measurement In this study, the effects of treated nonwoven fabrics containing a combination of glycerin and gluconic acid on the balance between beneficial and undesirable bacteria were measured. Escherichia coli (ATCC 10536) and Staphylococcus aureus (ATCC 6538), one Gram-negative and the other Gram-positive, were selected as representatives of undesirable bacteria. Lactobacillus plantarum (LB931, clinical isolate) and Lactobacillus were used as representatives of beneficial bacterial groups.

[0085] A pilot-scale flexographic printer (Anilox 10) was used to apply a dry coating containing gluconic acid and glycerin to nonwoven fabrics. The dry coating also contained NaOH to equilibrate the pH to 3.4. Tinopal was added as a fluorescent additive to ensure uniform printing by visually inspecting the treated nonwoven fabrics under UV light. The components of the skincare composition for bacterial growth measurement are shown in Table 8.

[0086] [Table 9]

[0087] Thin agar plates containing a 1% nutrient solution were prepared. Nutrients were added to more closely resemble skin. Three test bacteria were seeded on the surface of three different agar plates, with an initial concentration of approximately Log 4 cfu / ml. The diameter of the agar plate surface was 9 cm. Circles (2.5 cm in diameter) of treated nonwoven fabric and control nonwoven fabric were placed over the bacteria seeded on the agar plate surface in close contact, and incubated overnight at 35°C / 37°C. The following day, the bacteria under the test samples were counted. Bacteria count per square centimeter, Log cfu / cm² 2 This can be seen in Table 9.

[0088] The starting value is the number of bacteria before culturing. The control nonwoven fabric is a nonwoven fabric that does not contain gluconic acid and glycerin after culturing, while the treated nonwoven fabric is a nonwoven fabric that contains gluconic acid and glycerin after culturing.

[0089] The results of the bacterial growth measurement are shown in Table 9.

[0090] [Table 10]

[0091] Measurements of bacterial growth showed significant growth of all three tested bacterial species under untreated nonwoven fabric. Under nonwoven fabric treated with a skincare composition containing gluconic acid and treated glycerin, the growth of undesirable species, Escherichia coli (ATCC 10536) and Staphylococcus aureus (ATCC 6538), was reduced compared to the beneficial Lactobacillus plantarum (LB931, clinical isolate). From these results, it is clear that skincare compositions containing glycerin and gluconic acid are beneficial in maintaining the balance of the skin microbiome.

Claims

1. An absorbent sanitary article comprising a liquid-permeable top sheet and an absorbent core, wherein the top sheet is provided with a skincare composition, the skincare composition being provided on at least the side of the top sheet facing the user when the absorbent sanitary article is worn by the user, the absorbent sanitary article being characterized in that the skincare composition is a dry coating comprising gluconic acid and a water-miscible medium, such as glycerin, propylene glycol and / or PEG.

2. The amount of the water-miscible medium was measured over the area to be coated, and was between 0.04 and 9.0 g / m². ２ The article according to claim 1, which is within the range.

3. The article according to claim 1 or 2, wherein the amount of the water-miscible medium is at least 20% by weight, and optionally 20 to 90% by weight, of the dry coating.

4. The article according to any one of claims 1 to 3, wherein the water-miscible medium is glycerin.

5. The amount of gluconic acid, measured over the coated area, was 0.01 to 4.0 g / m². ２ The article according to claim 1, which is within the range.

6. The article according to any one of claims 1 to 5, wherein the dry coating does not contain a preservative.

7. The article according to any one of claims 1 to 6, wherein the dry coating has a water activity of less than 0.7 or less than 0.

6.

8. The article according to any one of claims 1 to 7, wherein the amount of gluconic acid is 5 to 40% by weight of the dry coating.

9. The article according to any one of claims 1 to 8, wherein the dry coating further comprises a surfactant.

10. The article according to any one of claims 1 to 9, wherein the top sheet is a nonwoven web material or a perforated plastic film.

11. The aforementioned top sheet has a density of 10-50 g / m². ２ An article according to any one of claims 1 to 10, having a dry basis weight.

12. The article according to any one of claims 1 to 11, wherein the absorbent core comprises 10 to 100 wt% of a superabsorbent polymer.

13. The article according to any one of claims 1 to 12, wherein the dry coating is distributed essentially uniformly on the top sheet.

14. The article according to any one of claims 1 to 13, wherein the dry coating is applied in a pattern that covers 10 to 90% of the area of ​​the top sheet.

15. The article according to any one of claims 1 to 14, wherein the absorbent core is disposed between the top sheet and the liquid-impermeable back sheet.

16. The article according to any one of claims 1 to 15, wherein the article is a diaper, an incontinence shield, a sanitary napkin, a panty liner, a tampon, or a wound dressing.

17. Use of the absorbent sanitary article according to any one of claims 1 to 16, for adjusting or maintaining the pH of the skin in contact with the article to a value of 3.5 to 5.5 by measuring it by the method disclosed herein.

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