Personal hygiene product

Abstract

To provide a personal hygiene product with improved wet lubricity and / or reduced skin irritancy.SOLUTION: A personal hygiene product comprises at least a first layer having a top surface and a bottom surface, where at least the first layer comprises a skin care additive, where the skin care additive is a diester which is the reaction product of a fatty alkoxylated ester and a straight, branched or aromatic polyol or polyacid.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a personal hygiene product comprising at least a first layer having a top surface and a bottom surface and a second layer having a top surface and a bottom surface, wherein at least the first layer comprises a diester skin care additive that is the reaction product of a fatty alkoxylated ester and a linear, branched, or aromatic polyol or polyacid. The skin care additive provides improved wet lubrication and / or reduced skin irritation. The present invention also relates to providing the care additive as a coating on the personal hygiene product. The present invention also provides the use of such a personal hygiene product comprising the skin care additive to prevent or alleviate dermatitis, particularly diaper rash. [Background technology]

[0002] Personal hygiene products of all kinds have grown in popularity and type since the late 19th century, and consumers now have a wide selection in terms of cost and quality of personal hygiene products available on the market. Such products are intended for use in direct contact with a person's skin, often in direct contact with delicate and sensitive skin areas or types. Summary of the Invention [Problem to be solved by the invention]

[0003] Skin discomfort, damage, and infection due to abrasions, dermatitis, etc. resulting from (or caused by) the use of personal hygiene products are well known and documented. The stick-and-slip behavior of materials used to construct personal care hygiene products is known to contribute to user discomfort and skin damage (see Proc IMechE Part H: J Engineering in Medicine, p. 1-13, 2018: E-ISSN:2041-3033, journal code 8908934). One area of ​​widespread technical interest is the avoidance or reduction of dermatitis caused by the wearing of incontinence diapers (commonly referred to as diaper rash), a problem experienced by both babies and the elderly, whose skin tends to be thinner and more sensitive. Many solutions have been proposed to address this type of dermatitis problem, such as providing antibacterial agents in diapers (China Patent Application Publication No. 107647971), providing low-friction materials as textile layers that come into contact with the skin (Japan Patent Application Publication No. 2019-025148), and providing physical means in the fiber layers that come into contact with the skin to reduce the amount of moisture that comes into contact with the skin (Japan Patent Application Publication No. 2017-012319).

[0004] Additionally, providing facial tissue with balms or lotions to enhance user comfort has become popular in recent years. Such facial tissue products are particularly beneficial for use when a user is suffering from a cold or flu virus and symptoms include a runny nose. Increased nose blowing to combat increased nasal mucus often damages the skin around the nostrils, and skin damage is exacerbated by the rough nature of facial tissue materials.

[0005] In particular, increased friction due to wetting of fabric products is a common cause of skin irritation experienced when using hygiene products. This wet friction is particularly problematic when the skin-contacting layer of a personal hygiene product is made from a nonwoven fabric. Reducing wet friction between the skin and the (nonwoven) fabric of the personal hygiene product that comes into contact with the skin is one option to help reduce irritation from nonwoven products. However, particularly with diapers, skin irritation due to prolonged contact with surfactants or urine is inevitable, and incorporating a counter-irritant can help reduce skin irritation caused by these factors. Furthermore, as the body's response to irritation, blood flow to the irritated area increases, causing inflammation, so blood flow can be evaluated as an indicator of irritation. [Means for solving the problem]

[0006] The present invention seeks to provide a skin care additive that has utility in personal hygiene products so that the problems highlighted above can be avoided or alleviated. The present invention has particular utility in absorbent personal hygiene products where end users of such products typically experience such problems, but as discussed below, can also be useful in non-absorbent products.

[0007] Accordingly, the present invention provides a personal hygiene product comprising at least a first layer having a top surface and a bottom surface, wherein at least said first layer comprises a skin care additive, Provided is a personal hygiene product as claimed in the present disclosure, characterized in that said skin care additive is a diester that is the reaction product of a fatty alkoxylated ester and a linear, branched, or aromatic polyol or poly acid.

[0008] Also contemplated is a method in which the skin care additive is provided as a coating on at least the top surface of at least the first layer.

[0009] The present invention further provides the use of a personal hygiene product according to the first aspect of the invention to prevent or alleviate dermatitis. Alternatively, the present invention may be understood to provide a method of preventing or treating dermatitis by use of a personal hygiene product according to the first aspect of the invention.

[0010] Thus, according to a first aspect of the present invention there is provided a personal hygiene product comprising at least a first layer having a top surface and a bottom surface, at least said first layer comprising a skin care additive, A personal hygiene product is provided, characterized in that the skin care additive is a diester that is the reaction product of a fatty alkoxylated ester and a linear, branched, or aromatic polyol or polyacid.

[0011] Preferably, the personal hygiene product also includes at least a second layer having a top surface and a bottom surface.

[0012] The layers of a personal care product can be considered to have a layered structure, positioned adjacent to one another to create an overall product form. When a product includes a first layer and a second layer, the layers may be provided in contact with one another, or the layers may be separated by an additional layer interposed between the first and second layers. The first and second layers can be conveniently considered to have a bottom surface and a top surface, where the top surface is considered to be the surface in contact with the skin / air, and the bottom surface is considered to be the interior surface of the product (i.e., the surface in contact with the bottom surface of another layer or with additional layers, if present).

[0013] In particular, the personal hygiene product may be composed of multiple layers, in particular a total of three, four, or five layers (including the first and second layers). In this case, the top surface of the first layer should be understood as the outer, skin-contacting layer when the product is in use, and the bottom surface of the first layer is in contact with one of the bottom surfaces of the second layer or, if one or more additional layers are present, is separated from the bottom surface of the second layer by the additional layer(s). The top surface of the second layer should be understood as the opposite outer surface of the personal hygiene product; for example, in the case of a wipe, this top surface of the second layer may be intended as the skin-contacting surface, or, for example, in the case of a diaper or pad, this top surface may be intended to contact clothing, particularly underwear. The bottom surfaces of both the first and second layers can be understood as the interior of the personal hygiene product if at least two layers are present. Such layer arrangements will be well understood by those skilled in the art.

[0014] In accordance with the present invention, the skin care additive provides improved moisturizing and lubrication or reduced skin irritation, preferably both, such that the skin care additive is a dual function additive, and such additive provides a skin care benefit to the user when the personal hygiene product is being used. As will be understood by those skilled in the art, and as further described below, personal hygiene products may suitably include additional optional active additives that are also believed to provide such skin care benefits, such as skin moisturizing or skin cooling effects, and to avoid confusion with such skin care additives, the skin care additive of the present invention may be conveniently referred to herein as a "diester skin care additive."

[0015] The personal hygiene product may suitably be tissue, wipe, diaper, pad, feminine care product, or face mask. Tissue may include facial tissue or toilet tissue. Wipes may include baby wipes, infant wipes, sterile wipes, hand wipes (especially antibacterial hand wipes), facial or body wipes (sometimes called shower wipes). Diapers may include, for example, incontinence diapers for babies, adults, or children in the form of tab closure diapers, pull-up pants (typically used for infant toilet training and young children with incontinence), or underwear (typically used for older children and adults with incontinence). Pads may include, for example, nursing pads, bed pads, incontinence pads for both children and adults, and sanitary pads. Feminine care products may include, for example, sanitary napkins and tampons. Typically, personal hygiene products include at least a first layer and at least a second layer, although wipes may often preferably consist of only the first layer. This is preferably the case when the wipes are designed to be suitable for flushing as a disposal means as minimising the overall bulk of the product allows such products to be flushed relatively easily, and this can also allow the product to break down more quickly after it has been flushed to avoid undesirable clogging in sanitation systems.

[0016] Of course, it will be appreciated that the application of skin care additives may also be useful in medical products such as, for example, anti-bed sore cushions and wound management products such as closing strips, wound dressings, etc. However, such medical products are not within the scope of the invention claimed in this disclosure, which is limited to personal hygiene products.

[0017] Preferably, the personal hygiene product further comprises at least one absorbent layer disposed between the first layer and the second layer, so that the personal hygiene product is an absorbent hygiene product.Since the problem of dermatitis may be exacerbated in situations where the user's skin is in prolonged contact with moisture, such as when using absorbent hygiene products, providing such a skin care additive of the type described in the present disclosure has particular advantages when provided in an absorbent hygiene product.Suitably, the absorbent hygiene product can be a diaper, a pad, or a feminine care product.Preferably, the absorbent hygiene product is a diaper.

[0018] Preferably, the diester skin care additive comprises two fatty alkoxylated moieties of structure (I):

[0019] [ka]

[0020] where R1 is a saturated or unsaturated, substituted or unsubstituted, straight-chain, branched, or aromatic fatty acid moiety having a carbon chain length of from about 6 to about 30 atoms; Each x and y is independently zero or an integer from 1 to 200, with the proviso that the sum of x and y in each fatty alkoxylated moiety is independently from 1 to 300, and the sum of all x and y in the diester does not exceed 800.

[0021] More preferably, the diester skin care additive comprises a linear, branched, or aromatic polyol or polyacid of formula (II):

[0022] [ka]

[0023] where M1, M2, and M3 are independently hydroxy, two single bonded hydrogens, or double bonded oxygen; Z p , Z q and Z r are independently hydrogen or hydroxy; p, q, and r are independently 0 or 1, provided that the sum of p+q+r is at least 2; w is 0 or an integer of 1 to 20.

[0024] More preferably, the diester skin care additive comprises an alkoxylated diester of myristyl alcohol and adipic acid. Most preferably, the diester skin care additive is di-PPG-2 myreth-10 adipate.

[0025] As will be understood by those skilled in the art, treat rate is a term of art and the treat rate weight % is calculated based on the weight of the layer in which the additive is incorporated or applied (i.e., relative to the layer treated with the additive), and not as a weight % relative to the total weight of the hygiene product.

[0026] Preferably, personal hygiene products include a treat rate of at least 0.5% by weight of the diester skin care additive. Treat rates below 0.5% by weight are less preferred, but these can still provide skin care benefits if formulated in combination with alternative / additional active additives, such as antimicrobial agents. However, for reasons of formulation cost and time, and for ease of formulation since potential interactions between multiple active ingredients do not have to be considered, it is preferred to use the diester skin care additive as the only active skin care additive.

[0027] Preferably, the personal hygiene product comprises said diester skin care additive at a treat rate of less than 5% by weight, above which no additional skin care benefit was observed.

[0028] More preferably, the personal hygiene product comprises the diester skin care additive at a treat rate of 0.5% to 3.0% by weight, and most preferably at a treat rate of 0.75% to 2.5% by weight. Ideally, the personal hygiene product comprises the diester skin care additive at a treat rate of about 1% to about 2% by weight. Such a treat rate has been found to provide an optimal balance between providing the skin care benefit of improved wet lubrication and providing the skin care benefit of reduced skin irritation, and is particularly well suited for absorbent hygiene products, especially diapers.

[0029] Transepidermal water loss (TEWL) can be measured to determine the relative skin condition of an individual. Damaged skin loses its ability to regulate water loss, resulting in increased water loss across the skin barrier. Therefore, TEWL is a convenient means of assessing the effectiveness of the diester skin care additives of the present invention.

[0030] As mentioned above, the personal hygiene product may preferably further comprise additional additives. Such additional additives may be selected from one or more of the following additives: known hygiene finishes, lanolin, botanicals, phase change materials, and emollients, among others. The presence of additional additives depends on the type of personal hygiene product, and suitable additional additives will be known to those skilled in the art. For example, if the personal hygiene product is an absorbent hygiene product, it may be particularly preferable to include a hygiene finish, and if the personal hygiene product is a nursing pad, it may be particularly preferable to include lanolin. However, it may be particularly preferable to include a phase change material in order to maintain a beneficial temperature for the skin in contact with the personal hygiene product. The use of such a phase change material in a personal hygiene product may have the additional benefit of providing some physical relief to the user of the personal hygiene product when irritation has already occurred and the skin in contact with the personal hygiene product feels hot and uncomfortable.

[0031] Optionally, the personal hygiene product may further comprise a solvent or diluent, which can act as a carrier for the skin care additive of the present invention and / or for other additives desirably provided in the personal hygiene product. The presence of a solvent or diluent may be particularly preferred when the diester skin care additive is applied to the relevant layer of the personal hygiene product as a coating.

[0032] Optionally, the personal hygiene product may further comprise a stabilizer or emulsifier. Sorbitan fatty acid esters (e.g., Spans), their corresponding polyoxyethylene (POE) adducts (e.g., Tweens), and hydrogenated castor oil derivatives (e.g., Crodurets) are particularly preferred stabilizers or emulsifiers for use in the present invention. The stabilizer may be present to help maintain the diester-based skin care beneficial additive as an emulsion in the solvent, as this can help control its application to the relevant layer of the personal hygiene care product during manufacture. The presence of a stabilizer is particularly preferred when the solvent (if present) is water. Thus, the personal hygiene product may comprise at least the first layer comprising the diester skin care additive, the solvent, and the stabilizer.

[0033] Notwithstanding the above, the diester skin care additive is preferably used neat, and therefore the presence of solvents or diluents and / or stabilizers or emulsifiers is a less preferred embodiment.

[0034] Most preferably, at least a first layer of the personal hygiene product comprises a coating containing the diester skin care additive, wherein the coating is present on at least a top surface of the first layer. Alternatively, the diester skin care additive may be impregnated into the first layer or incorporated in some other manner, such as by mechanically embedding an encapsulated material containing the skin care additive into at least the first layer. However, providing the skin care additive as a coating applied to at least a top surface of the first layer of the personal hygiene product is preferred for ease of manufacturing.

[0035] Furthermore, the second layer of the personal hygiene product may further comprise a coating comprising a skin care additive, the coating being present on at least a top surface of the second layer, This arrangement is particularly preferred when the personal hygiene product is a wipe and both the top surface of the first layer and the top surface of the second layer may come into contact with a user's skin.

[0036] Additionally or alternatively, the personal hygiene product may further include a sealing means having a top surface and a bottom surface, the sealing means including a coating containing a skin care additive, the coating being present on at least the top surface of the sealing means. Such an arrangement is particularly preferred when the hygiene product is a diaper, and the sealing means can be leg cuffs or a waistband, preferably leg cuffs, which also come into contact with the user's skin to prevent leakage of urine and feces. Since leg cuffs, in particular, can provide a high degree of friction to the user's skin when the user moves around, the use of a diester skin care additive may be particularly preferred. The sealing means has a layered structure having a top surface and a bottom surface, the top surface being understood to be the skin-contacting surface when the personal hygiene product is in use, and the bottom surface in this case being understood to be the opposite surface to the skin-contacting surface. The sealing means is added to the laminated structure that constitutes the main body of the personal hygiene product, as described above.

[0037] Suitably, the coating of the personal hygiene product may be provided as a continuous or discontinuous layer. It may be preferred to provide the coating as a discontinuous layer so that the layer is permeable, and such an embodiment is preferred when the personal hygiene product comprises an absorbent layer for the purpose of containing bodily fluids such as urine, breast milk or menstrual discharge.

[0038] Preferably, the personal hygiene product comprises at least one layer formed from a textile. More preferably, the personal hygiene product may comprise at least one layer formed from a nonwoven fabric.

[0039] Additionally or alternatively, the personal hygiene product can include at least one layer formed from paper pulp. Preferably, the paper pulp is obtained from recycled paper pulp. Such an embodiment is preferred when the personal hygiene product is a diaper and the absorbent layer is formed from paper pulp, or when the personal hygiene product is tissue, particularly toilet tissue. One drawback identified by users of toilet tissue made from recycled paper pulp is that the tissue has a rough feel during use or is more abrasive to the skin compared to virgin material alternatives. The diester skin care additive of the present invention provides improved wet lubricity that can reduce user discomfort, making such recycled paper pulp products more acceptable to consumers.

[0040] In some particularly preferred embodiments, the second layer of the personal hygiene product is a breathable waterproof layer. This may be particularly preferred when the personal hygiene product is a diaper or pad, which preferably includes an absorbent layer for the purpose of containing bodily fluids such as urine, breast milk, or menstrual discharge. In this case, the second layer does not include a diester skin care additive. The use of a diester skin care additive in such personal hygiene products is particularly useful because the additive can advantageously provide both improved wet lubrication and reduced skin irritation. Thus, preferably, the personal hygiene product is a diaper or pad.

[0041] Also provided is a method for providing a skin care additive as a coating on at least the top surface of at least a first layer. Suitable methods for providing the coating can be by spraying, roller, bar, blade, knife or foam application. Suitable equipment for carrying out the coating method is known to those skilled in the art and can be used without technical difficulty.

[0042] Preferably, the method includes providing a diester skin care additive-containing coating in the form of a dispersion, emulsion, or solution, which coating may include additional materials as described above in connection with the diester skin care additive composition.

[0043] Optionally, the method includes providing a diester skin care-containing coating on top of at least the second layer. Such a method is preferred when the personal hygiene product is a tissue or wipe.

[0044] Additionally or alternatively, the use of the personal hygiene product as described above for preventing or alleviating dermatitis is provided. In particular, it is envisioned that the use of the diaper as described above can prevent or alleviate diaper rash dermatitis. In this case, the moist environment caused by sweat or urine when the hygiene product is used contributes to skin irritation, and furthermore, physical abrasion of the skin due to contact with the top surface of the first layer of the product contributes to further skin damage or hinders healing. The personal hygiene product containing the diester skin care additive of the present invention alleviates both of these negative contributing factors.

[0045] Additionally or alternatively, there is provided the use of the personal hygiene product as described above for preventing or alleviating bed sores. In particular, it is envisaged that the use of the pad as described above makes it possible to avoid or alleviate bed sores, in particular due to the moisturizing and lubrication provided by the diester skin care additive.

[0046] Additionally, use of personal hygiene products as described above desirably makes the non-absorbent hygiene product more comfortable for the end user, e.g., in the case of tissues, improving the perceived roughness of the product and advantageously reducing user discomfort experienced during tampon insertion. This improved user comfort is a result of the improved wet lubricity of the personal hygiene product provided by the diester skin care additive.

[0047] All of the features described herein may be combined with any of the above aspects in any combination. Example

[0048] The present invention will now be further described, by way of example only, with reference to the following examples and figures. [Brief explanation of the drawings]

[0049] [Figure 1] FIG. 1 shows the overall mean TEWL of the test panelists for SLS and the exemplary materials. [Figure 2] FIG. 2 shows the overall mean change in inflammation for the study panelists calculated using Laser Doppler. [Figure 3] FIG. 3 shows the average dry and wet limiting friction data obtained for 15 gsm spunbond polypropylene fabric samples. [Figure 4] FIG. 4 shows the average dry and wet limiting friction data obtained for 15 gsm spunbond polypropylene fabric samples. [Figure 5] FIG. 5 shows the average dry and wet limiting friction force data obtained for the 10 gsm polypropylene fabric samples. [Figure 6] FIG. 6 shows the average dry and wet limiting friction force data obtained for the 10 gsm polypropylene fabric samples. [Figure 7] FIG. 7 shows the average dry and wet limiting friction force data obtained for 10 gsm polypropylene fabric samples and example materials at various treat rates. [Figure 8] FIG. 8 shows the test panel's overall average TEWL for the sanitary finish comparing the sanitary finish in combination with the exemplary materials and the sanitary finish in combination with a glycerin-based emollient. [Figure 9] FIG. 9 shows the test panel's overall average TEWL for the sanitary finish, comparing the sanitary finish with the exemplary materials and the sanitary finish with an ester-based emollient. [Example]

[0050] All tests and physical properties described above were determined at atmospheric pressure and room temperature (i.e., about 20° C.) unless otherwise specified in this disclosure or in the referenced test methods and procedures.

[0051] Example 1 - Irritation reduction test Textile Processing A 10 gsm polypropylene nonwoven fabric was cut into 11 mm diameter circles. Each circle was individually treated with an aqueous dispersion and then dried to achieve a treatment rate of either: a) 1% sodium lauryl sulfate (SLS, Sample A) based on fabric weight; or b) 1% SLS and 2% di-PPG-2 myreth-10 adipate (a diester skin care additive according to the present invention, Sample B), as a percentage based on fabric weight. SLS is a known skin irritant and therefore provides a good model for assessing skin irritation in subjects / panelists.

[0052] Stimulus Panel Survey A stimuli panel study was conducted with nine panelists, each of whom was allowed to acclimate to the laboratory environment at 20°C and 45% relative humidity for 20 minutes before beginning the testing detailed below.

[0053] For each panelist, three test sites were identified and marked on the volar forearm (i.e., a total of six test sites were evaluated per panelist). An AquaFlux AF200 device was used to obtain initial transepidermal water loss (TEWL) measurements to confirm the absence of initial skin irritation at each of the six test sites.

[0054] Initial readings of inflammation were also obtained using laser Doppler. Laser Doppler readings are used to measure cutaneous blood perfusion, which is an indicator of the inflammation present in the skin at the test site. The laser Doppler device measures blood perfusion across the test area and displays the resulting data as a perfusion heat map. The device also assigns a value to each color depicted in the perfusion heat map, allowing the device to calculate a total irritation reading across the test area, which can be expressed as a number.

[0055] For each panelist, three test circles (prepared as described above) were applied to the skin under an occlusive patch and left in place for 24 hours. The same six test sites were used for each panelist, but the test material at each site was randomly assigned among participants.

[0056] After 24 hours, panelists were again acclimated to a laboratory environment of 20°C and 45% relative humidity for 20 minutes. TEWL was measured using the POST (post occlusion stress test) protocol. In this test, the occlusive patch was removed along with the fabric sample, the test site was wiped dry, and TEWL measurements were then immediately obtained using the same AquaFlux AF200 device. TEWL was measured until the peak water loss rate and for the following 5 minutes. Results were a measurement of total water loss for the 5 minutes after the peak water loss rate. Once the TEWL measurement was completed, laser Doppler images were taken again and compared with the initial measurements.

[0057] In the panel test, as described above, Sample A was a fabric treated with a finish containing SLS at a 1% treat rate, and Sample B was a fabric treated with a finish containing SLS at a 1% treat rate and a diester skin care additive at a 2% treat rate.

[0058] Figure 1 shows the overall average TEWL for all panelists. The results show a 31% reduction in skin water loss when using the diester skin care additive.

[0059] Figure 2 shows the overall mean change in inflammation for all panelists, calculated using Laser Doppler. The results show a 49% reduction in inflammation for Sample B compared to Sample A.

[0060] Example 2 - Friction Reduction Test In this study, two types of nonwoven fabrics were tested: 1) 15 gsm spunbond polypropylene and 2) 10 gsm polypropylene. The nonwoven fabric samples tested were coated with either a) a commercial sanitary finish product or b) an emulsion containing both a commercial sanitary finish and di-PPG-2 myreth-10 adipate, a diester skin care additive according to the present invention. Two commercial sanitary finish products, Stantex S 6757 (from Pulcra) and Cirrasol Care (from Croda), both of which provide a hydrophilic finish to polypropylene nonwoven fabrics, were used in this study. In general, such sanitary finish products are typically applied to nonwoven fabrics for use in absorbent personal hygiene products to allow rapid wicking of liquids from the skin-contacting textile layer to the underlying absorbent layer.

[0061] Skin friction measurements were performed using a Lloyd LRX tensile tester using a polyolefin-based synthetic skin substitute. The synthetic skin was placed over a 20 cm test piece of nonwoven fabric, and the limiting force was measured.

[0062] The nonwoven fabrics were left in a temperature- and humidity-controlled environment at 22°C and 50% relative humidity for a minimum of 24 hours. Three sets of friction measurements were performed on the treated nonwoven fabrics for each test sample, with three samples tested for each treatment combination. Wet friction measurements were performed following the dry friction measurements. Wet friction measurements were performed by wetting the test fabric sample with 0.2 g of deionized water, which was then evenly sprayed onto the specimen with a spray bottle. Three measurements were then performed on each wet sample using the same procedure as for the dry measurements.

[0063] Figure 3 shows average dry and wet threshold friction data obtained for 15 gsm spunbond polypropylene fabric samples, where Sample A was finished with a 0.5% Stantex S 6757 treat rate and Sample B was finished with a 0.5% Stantex S 6757 treat rate and a 2% diester skin care additive treat rate. It can be seen that Sample A exhibited high skin friction, which increased when the sample was wet. Meanwhile, Sample B exhibited a 68% lower skin friction when the fabric sample was dry compared to Sample A, and experienced a slight decrease, rather than an increase, in skin friction when the sample was wet.

[0064] Figure 4 shows average dry and wet threshold friction data obtained for 15 gsm spunbond polypropylene fabric samples, where Sample A was finished with a 0.5% Cirrasol Care treat rate and Sample B was finished with a 0.5% Cirrasol Care treat rate and a 2% diester skin care additive treat rate. It can be seen that Sample A exhibited high skin friction, which decreased slightly when the sample was wet. Meanwhile, Sample B exhibited a 36% lower skin friction when the fabric sample was dry compared to Sample A, and further decreased skin friction when the sample was wet.

[0065] Figure 5 shows average dry and wet threshold friction data obtained for 10 gsm polypropylene fabric samples, where Sample A was finished with a 0.5% Stantex S 6757 treat rate and Sample B was finished with a 0.5% Stantex S 6757 treat rate and a 2% diester skin care additive treat rate. It can be seen that for this fabric sample, Sample A exhibited lower skin friction when dry compared to a 15 gsm spunbond polypropylene fabric. However, this skin friction increased when the sample was wet. In this case, Sample B did not exhibit a reduction in skin friction when the fabric sample was dry compared to Sample A, but exhibited a significant decrease in skin friction when the sample was wet.

[0066] Figure 6 shows average dry and wet threshold friction data obtained for 10 gsm polypropylene fabric samples, where Sample A was finished with a 0.5% Cirrasol Care treat rate and Sample B was finished with a 0.5% Cirrasol Care treat rate and a 2% diester skin care additive treat rate. It can be seen that Sample A had relatively low dry skin friction, but this skin friction increased when the sample was wet. For Sample B, the dry skin friction decreased, and when Sample B was wet, the skin friction decreased even further.

[0067] Various treat rates of diester skin care additive were also tested using the procedure outlined above. Figure 7 shows the average dry and wet threshold friction force data obtained for 10 gsm polypropylene fabric samples, where Sample A was finished with a 0.5% Cirrasol Care treat rate, Sample B was finished with a 0.5% Cirrasol Care treat rate and a 2% diester skin care additive treat rate, Sample C was finished with a 0.5% Cirrasol Care treat rate and a 1% diester skin care additive treat rate, and Sample D was finished with a 0.5% Cirrasol Care treat rate and a 0.5% diester skin care additive treat rate. It can be seen that the presence of the diester skin care additive at 1% and 2% treat rates reduced both wet and dry skin friction forces, with a greater reduction observed for the wet sample. The presence of the diester skin care additive at a relatively low treat rate of 0.5% decreased the observed wet skin friction but increased the dry skin friction relative to Sample A. Since wet friction is known to be a major factor in skin damage (especially during diaper use), it is believed that the increase in dry skin friction observed in this sample (which was still lower than that observed for the 15 gsm spunbond polypropylene fabric sample with Stantex S 6757 sanitary finish) may provide a skin care benefit during use.

[0068] Summary of results The above tests showed a measurable reduction in irritation / inflammation from prolonged contact with treated nonwovens when the nonwovens contained a 2% treatment rate of the diester skin care additive. This was demonstrated by a reduction in transepidermal water loss, indicating less damage to the skin barrier. The reduction in irritation was further demonstrated by a reduction in blood perfusion as measured by laser Doppler.

[0069] Furthermore, in addition to reducing skin irritation / inflammation, the same diester skin care additive can be used at a treat rate of 1% or 2% by weight of the nonwoven to consistently reduce wet friction forces while also reducing or maintaining dry friction performance.

[0070] Example 3 - Comparative Irritation Reduction Test for Glycerin-Based Emollients Textile Processing A 10 gsm polypropylene nonwoven fabric was cut into 11 mm diameter circles. Each circle was individually treated with an aqueous dispersion and then dried to achieve a treatment rate of a) 0.6% mild hygiene finish (Cirrasol™ Care from Croda, Sample A), or b) 0.6% mild hygiene finish and 12% Di-PPG-2 Myreth-10 Adipate (a diester skin care additive according to the invention, Sample B), or c) 0.6% mild hygiene finish and 12% glycerin-based emollient (Sample C). Treat rates are expressed as a percentage based on the mass of the fabric.

[0071] Stimulus Panel Survey A stimuli panel study was conducted with 16 panelists, each of whom was allowed to acclimate to the laboratory environment at 20°C and 45% relative humidity for 20 minutes before beginning the testing detailed below. For each panelist, three test sites were identified and marked on the volar forearm (i.e., a total of six test sites were evaluated per panelist). An AquaFlux AF200 device was used to obtain initial transepidermal water loss (TEWL) measurements to confirm the absence of initial skin irritation at each of the six test sites.

[0072] For each panelist, three test circles (prepared as described above) were applied to the skin under an occlusive patch and left in place for 24 hours. The same six test sites were used for each panelist, but the test material at each site was randomly assigned among participants.

[0073] After 24 hours, the panelists were again acclimated to a laboratory environment of 20°C and 45% relative humidity for 20 minutes. TEWL was measured using a POST (post-occlusion stress test) protocol. In this test, the occlusive patch was removed along with the fabric sample, the surface moisture of the test site was wiped dry, and then TEWL measurements were immediately obtained using the same AquaFlux AF200 device. TEWL was measured until the peak water loss rate and for the following 5 minutes. The results were a measurement of the total water loss for the 5 minutes after the peak water loss rate.

[0074] In the panel test, as described above, Sample A was a fabric treated with only a hypoallergenic hygienic finish at a 0.6% treatment rate, while Sample B was a fabric treated with a finish containing 0.6% hypoallergenic hygienic finish and 12% diester skin care additive, and Sample C was a fabric treated with a finish containing 0.6% hypoallergenic hygienic finish and 12% glycerin-based emollient.

[0075] Figure 8 shows the overall average TEWL for all panelists. The results show that the diester skin care additive reduces skin irritation from nonwoven fabrics in contact with the skin, whereas the glycerin-based additive increases skin irritation, when compared to the mild sanitary finish alone.

[0076] Example 4 - Comparative Irritation Reduction Test for Ester-Based Emollients Textile Processing A 10 gsm polypropylene nonwoven fabric was cut into 11 mm diameter circles. Each circle was individually treated with an aqueous dispersion and then dried to achieve a treatment rate of a) 0.6% mild hygiene finish (Cirrasol™ Care from Croda, Sample A) based on the weight of the fabric, or b) 0.6% mild hygiene finish and 12% di-PPG-2 myreth-10 adipate (a diester skin care additive according to the invention, Sample B), or c) 0.6% mild hygiene finish and 12% saturated triester-based emollient (Crodamol™ GTCC, Sample C). Treat rates are expressed as a percentage based on the weight of the fabric.

[0077] Stimulus Panel Survey A stimulus panel study was conducted with 16 panelists, each of whom was allowed to acclimate to a laboratory environment of 20°C and 45% relative humidity for 20 minutes before beginning the testing detailed below.

[0078] For each panelist, three test sites were identified and marked on the volar forearm (i.e., a total of six test sites were evaluated per panelist). An AquaFlux AF200 device was used to obtain initial transepidermal water loss (TEWL) measurements to confirm the absence of initial skin irritation at each of the six test sites.

[0079] For each panelist, three test circles (prepared as described above) were applied to the skin under an occlusive patch and left in place for 24 hours. The same six test sites were used for each panelist, but the test material at each site was randomly assigned among participants.

[0080] After 24 hours, the panelists were again acclimated to a laboratory environment of 20°C and 45% relative humidity for 20 minutes. TEWL was measured using a POST (post-occlusion stress test) protocol. In this test, the occlusive patch was removed along with the fabric sample, the surface moisture of the test site was wiped dry, and then TEWL measurements were immediately obtained using the same AquaFlux AF200 device. TEWL was measured until the peak water loss rate and for the following 5 minutes. The results were a measurement of the total water loss for the 5 minutes after the peak water loss rate.

[0081] In the panel test, as described above, Sample A was a fabric treated with only a hypoallergenic sanitary finish at a 0.6% treatment rate, while Sample B was a fabric treated with a finish containing 0.6% hypoallergenic sanitary finish and 12% diester skin care additive, and Sample C was a fabric treated with a finish containing 0.6% hypoallergenic sanitary finish and 12% saturated triester emollient.

[0082] Figure 9 shows the overall average TEWL for all panelists. The results show that, compared to the mild sanitary finish alone, the diester skin care additive reduces skin irritation from nonwoven fabrics in contact with the skin, while the triester additive increases skin irritation.

Claims

1. 1. A personal hygiene product comprising at least a first layer having a top surface and a bottom surface, wherein at least said first layer comprises a skin care additive; 1. A personal hygiene product, characterized in that the skin care additive is a diester which is the reaction product of a fatty alkoxylated ester with a linear, branched or aromatic polyol or polyacid.

2. 10. The personal hygiene product of claim 1, further comprising at least a second layer having a top surface and a bottom surface.

3. 3. The personal hygiene product of claim 1 or 2, wherein the diester skin care additive comprises two fatty alkoxylated moieties of structure (I): 【Chemical 1】 where: R １ is a saturated or unsaturated, substituted or unsubstituted, straight-chain, branched or aromatic fatty acid moiety having a carbon chain length of from about 6 to about 30 atoms; Each x and y is independently 0 or an integer from 1 to 200, with the proviso that the sum of x and y in each fatty alkoxylated moiety is independently from 1 to 300, and the sum of all x and y in said diester does not exceed 800.

4. 4. A personal hygiene product according to any one of claims 1 to 3, wherein the linear, branched or aromatic polyol or polyacid is represented by formula (II): 【Chemistry 2】 where: M １ , M ２ and M ３ are independently hydroxy, two single-bonded hydrogens, or a double-bonded oxygen; Z ｐ , Z ｑ and Z ｒ are independently hydrogen or hydroxy; p, q, and r are independently 0 or 1, provided that the sum of p+q+r is at least 2; w is 0 or an integer of 1 to 20.

5. The personal hygiene product of any one of claims 1 to 4, wherein the diester skin care additive comprises an alkoxylated diester of myristyl alcohol and adipic acid.

6. 6. The personal hygiene product of claim 5, wherein the diester skin care additive is di-PPG-2 myreth-10 adipate.

7. 7. The personal hygiene product of any one of claims 1 to 6, comprising a treat rate of at least 0.5% by weight of the diester skin care additive.

8. 8. The personal hygiene product of any one of claims 1 to 7, comprising a treat rate of less than 5% by weight of the diester skin care additive.

9. 9. The personal hygiene product of any one of claims 1 to 8, comprising a treat rate of 0.5% to 3.0% by weight of the diester skin care additive.

10. 10. The personal hygiene product of any one of claims 1 to 9, comprising a treat rate of 0.75% to 2.5% by weight of the diester skin care additive.

11. The personal hygiene product of any one of claims 1 to 10, comprising a treat rate of about 1% to about 2% by weight of the diester skin care additive.

12. The personal hygiene product of any one of claims 1 to 11, further comprising a solvent or diluent.

13. 13. A personal hygiene product according to any one of claims 1 to 12, further comprising additional additives.

14. The personal hygiene product of any one of claims 1 to 13, further comprising a stabilizer.

15. 15. The personal hygiene product of any one of claims 1 to 14, wherein the first layer comprises a coating comprising the skin care additive, the coating being present on at least a top surface of the first layer.

16. 16. The personal hygiene product of claim 15, when dependent on any one of claims 2 to 14, wherein the second layer further comprises a coating comprising the skin care additive, the coating being present on at least a top surface of the second layer.

17. 17. The personal hygiene product of any one of claims 1 to 16, wherein the personal hygiene product further comprises a sealing means having a top surface and a bottom surface, the sealing means comprising a coating comprising the skin care additive, the coating being present on at least the top surface of the sealing means.

18. 18. The personal hygiene product of claim 15, 16 or 17, wherein the coating is provided as a continuous or discontinuous layer.

19. 19. The personal hygiene product of any one of claims 2 to 18, further comprising at least one absorbent layer disposed between the first layer and the second layer, such that the personal hygiene product is an absorbent hygiene product.

20. The personal hygiene product of any one of claims 1 to 19, wherein at least one layer is formed from a textile.

21. 21. The personal hygiene product of claim 20, wherein the textile is a nonwoven.

22. A personal hygiene product according to any preceding claim, wherein at least one layer is formed from paper pulp.

23. A personal hygiene product according to any preceding claim, wherein at least one layer is formed from recycled paper pulp.

24. A personal hygiene product according to any one of claims 2 to 23, wherein the second layer is a breathable waterproof layer.

25. The personal hygiene product according to any one of claims 1 to 24, wherein the personal hygiene product is a diaper or a pad.

26. Use of a personal hygiene product according to any one of claims 1 to 25 to prevent or alleviate dermatitis.

27. Use of a personal hygiene product according to any one of claims 1 to 25 for preventing or alleviating bedsores.

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