Patent Application
20130337710
In the discussion of the background that follows, reference is made to certain structures and/or methods. However, the following references should not be construed as an admission that these structures and/or methods constitute prior art. Applicants expressly reserve the right to demonstrate that such structures and/or methods do not qualify as prior art.
Products comprising a non-woven fabric or material intended to contact skin are well known in the art. Such products include absorbent products such as diapers, adult incontinence pads or briefs, feminine hygiene products (e.g., sanitary napkins), bandages, and the like. Personal care and Household wipes are also typically made of non-woven fabric. Prolonged skin contact with non-woven fabrics may result in discomfort due for instance to irritation by contact with the non-woven fabric.
There is an on-going unmet need in the art for products that include a non-woven surface intended to contact skin, such as wipes, diapers, adult incontinence products, and feminine hygiene products, where the non-woven surface has an improved tactile property. The present disclosure addresses this need.
The following summary is not an extensive overview. It is intended to neither identify key or critical elements of the various embodiments, nor delineate their scope.
Provided is a treated non-woven fabric having an improved tactile property. The treated non-woven fabric comprises a non-woven fabric comprising a functional additive in a suitable amount to improve a tactile property. Also provided is a non-woven product for use in contacting skin, wherein the product comprises a non-woven fabric to contact skin. The non-woven fabric is a treated non-woven fabric having an improved tactile property. Exemplary non-woven products are a diaper, an adult incontinence product, a feminine hygiene product and a wipe. A method for preparing a treated non-woven fabric having an improved tactile property is also provided. The method comprises the steps of contacting a surface of a non-woven fabric with an aqueous surface modifying composition comprising functional additive, and drying the contacted surface to produce the treated non-woven fabric. Contacting a surface may comprise spraying, brushing, rolling, dipping, or other methods of applying a surface modifying composition to a non-woven fabric surface.
The functional additive is selected from the group consisting of Additive A, Additive B, Additive C, Additive D, Additive E, Additive F, Additive G, Additive H (as each is described in columns 2 and 3 of Table 1); a blend of Additives G and F (“Additive BA”), a blend of Additives F and B (“Additive BB”) and a blend of Additives F and H (“Additive BC”). The non-woven fabric may comprise a plastic selected from the group consisting of polyester, polyamide, and polyolefin. Exemplary polyolefins are polypropylene and polyethylene. An exemplary polyester is polylactide.
In an embodiment, the functional additive may be present substantially on the surface of the non-woven fabric and optionally in voids present on the surface of the fabric. In another embodiment, the non-woven fabric is partially or fully impregnated with the functional additive.
In an embodiment, the functional additive on the non-woven fabric is Additive A and the non-woven fabric comprises: i) about 0.007 to about 0.054 g Additive A per square meter non-woven fabric; or ii) about 0.05 to about 0.040 wt. % Additive A (relative to dry untreated fabric weight).
In another embodiment, the functional additive on the non-woven fabric is Additive B and the non-woven fabric comprises: i) about 0.095 to about 0.135 g Additive B per square meter non-woven fabric; or ii) about 0.70 to about 1.0 wt. % Additive B (relative to dry untreated fabric weight).
In another embodiment, the functional additive on the non-woven fabric is Additive C and the non-woven fabric comprises: i) about 0.068 to about 0.135 g Additive C per square meter non-woven fabric; or ii) about 0.50 to about 1.0 wt. % Additive C (relative to dry untreated fabric weight).
In another embodiment, the functional additive on the non-woven fabric is Additive D and the non-woven fabric comprises: i) about 0.081 to about 0.135 g Additive D per square meter non-woven fabric; or ii) about 0.60 to about 1.0 wt. % Additive D (relative to dry untreated fabric weight).
In another embodiment, the functional additive on the non-woven fabric is Additive E and the non-woven fabric comprises: i) about 0.081 to about 0.135 g Additive E per square meter non-woven fabric; or ii) about 0.60 to about 1.0 wt. % Additive E (relative to dry untreated fabric weight).
In yet another embodiment, the functional additive on the non-woven fabric is Additive F and the non-woven fabric comprises: i) about 0.203 to about 0.324 g Additive F per square meter non-woven fabric; or ii) about 1.5 to about 2.4 wt. % Additive F (relative to dry untreated fabric weight).
In another embodiment, the functional additive on the non-woven fabric is Additive G and the non-woven fabric comprises: i) about 0.3513 to about 0.378 g Additive G per square meter non-woven fabric; or ii) about 2.6 to about 2.84 wt. % Additive G (relative to dry untreated fabric weight).
In another embodiment, the functional additive on the non-woven fabric is Additive H and the non-woven fabric comprises: i) about 0.230 to about 0.270 g Additive H per square meter non-woven fabric; or ii) about 1.7 to about 2.0 wt. % Additive H (relative to dry untreated fabric weight).
In yet another embodiment, the functional additive on the non-woven fabric is Blend BA, wherein the ratio of Additive G to Additive F is about 1:1.
In another embodiment, the functional additive on the non-woven fabric is Blend BB, wherein the ratio of Additive F to Additive B is about 10:3.
In another embodiment, the functional additive on the non-woven fabric is Blend BC, wherein the ratio of Additive F to Additive H is about 1:1.
For the purpose of illustrating the various compositions and methods, there are depicted in the drawings certain embodiments. However, the compositions and their methods of use are not limited to the precise arrangements and instrumentalities of the embodiments depicted in the drawings.
The FIGURE is a chart depicting the pairwise comparison of a series of treated non-woven fabric samples compared to a control (untreated non-woven fabric sample) regarding sensory assessment (softness/smoothness). The product used for treatment is listed next to the relevant data. The weight percent of product on the non-woven fabric sample is shown in parentheses. Panelists (n=3) were asked to rate each test sample from −1 to 1, with 0 being similar to control, −1 as exceptionally bad and +1 being exceptionally good relative to the control and −0.5 and +0.5 used to distinguish between slightly bad and slightly good respectively relative to the control. Filled symbol: Wilcoxon test; P-value≧0.1. Empty symbol: lower 90% confidence (l.c.b.) bound for zero values>0.66667.
As envisioned in the present disclosure with respect to the disclosed methods and compositions of matter, in one aspect the embodiments of the disclosure comprise the components and/or steps disclosed therein. In another aspect, the embodiments of the disclosure consist essentially of the components and/or steps disclosed therein. In yet another aspect, the embodiments of the disclosure consist of the components and/or steps disclosed therein.
There is a need in the art for non-woven fabrics, and products having non-woven fabrics, having improved tactile properties. Provided herein is a treated non-woven fabric having an improved tactile property, a product comprising the treated non-woven fabric, and a method of producing the treated non-woven fabric that meets these needs.
As used herein, each of the following terms has the meaning associated with it in this section.
The articles “a” and “an” are used herein to refer to one or to more than one (i.e., to at least one) of the grammatical object of the article. By way of example, “an element” means one element or more than one element.
The term “about” will be understood by persons of ordinary skill in the art and will vary to some extent depending on the context in which it is used. As used herein, “about” is meant to encompass variations of ±20%, more preferably ±10%, more preferably ±5%, even more preferably ±1%, and still more preferably ±0.1%.
As used herein, “fabric” refers generally to a material having a two dimensional character, i.e., the length and width of the material is much greater than the thickness. A surface of the fabric, as used herein, generally is defined by the length and width dimensions.
As used herein, a “non-woven” fabric or material refers to a fabric or material assembled from interlocking fibers that are not interlocked by weaving. A non-woven fabric is typically made of plastic resins. Fibers of the plastic resin may be assembled by mechanical, chemical and/or thermal methods to form a non-woven fabric. Exemplary methods of preparing a non-woven fabric or material include meltblowing, spinbonding, airlaying, and a spunlace process.
As used herein, a “non-woven product” refers to a product that comprises a non-woven surface. The product may consist of a non-woven fabric/material or the product may comprise a non-woven surface, for instance, a non-woven fabric as part of, or all of, the external surface of the product. Exemplary non-woven products include, but are not limited to, diapers, adult incontinence products, feminine hygiene products, and wipes such as baby wipes.
As used herein, a “functional additive” refers to a compound or composition of compounds that, when added, coated, sprayed, brushed and/or otherwise applied to a non-woven fabric/material, contributes a new property, improves an existing desirable property, and/or reduce an existing undesirable property of the non-woven fabric/material.
As used herein, a “surface modifying composition” refers to a composition comprising or consisting of a functional additive.
As used herein, a surface “treated with a surface modifying composition” means a surface modifying composition is added, coated, sprayed, brushed and/or otherwise applied to the surface.
As used herein, a “treated non-woven product” refers to a non-woven product wherein the non-woven surface has been treated with a surface modifying composition.
As used herein, a “tactile property” refers to a property that is perceived by touch. Exemplary tactile properties include, but are not limited to, softness and smoothness.
As used herein, an “improved tactile property” of a treated non-woven product refers to a tactile property that is assessed to be better relative to the corresponding non-woven product that is not treated. The improvement may be introduction of a new property, improvement of an existing desirable property, and/or reduction of an existing undesirable property of the untreated non-woven fabric/material. The assessment may be qualitative or quantitative. Art-accepted methods of assessing tactile properties are known to the skilled artisan. An exemplary, but not limiting, method is described in the Examples.
It is understood that any and all whole or partial integers between any ranges set forth herein are included herein.
Provided herein is a treated non-woven fabric having an improved tactile property. Also provided is a treated non-woven product. The treated non-woven product comprises a non-woven product comprising a non-woven fabric surface, wherein the non-woven fabric surface comprises a functional additive. The functional additive may be present substantially only on the surface as a coating. Optionally, a surface coating may also include functional additive partially within the voids that might be present on the surface. Alternatively, the non-woven fabric may be impregnated with the functional additive and thus, in addition to functional additive on the surface, may comprise the functional additive to a greater depth within the thickness of the fabric. The impregnation may be partial or complete through the thickness of the fabric. As used herein, the phrase “contacting a surface of a non-woven” encompasses all of these embodiments, unless otherwise specified.
The functional additive may be present substantially across the entire non-woven two-dimensional surface, or may be present across only a fraction of the non-woven two-dimensional surface. For instance, in a product wherein only a part of the non-woven surface is intended to contact skin, the functional additive may be present substantially only on and/or within that portion of the non-woven surface that is intended to contact skin. A non-woven fabric may comprise a functional additive on one or both two dimensional surfaces. Where both two dimensional surfaces of a non-woven fabric comprise a functional additive, the additive may be the same on both surfaces, or may be different.
Table 1 lists the functional additives A through H discovered to improve a tactile property of a non-woven fabric and provides a description of the components of the additives. An exemplary product as Additive A is sold under the trademark COSMEDIA® SP (BASF Corporation). An exemplary product as Additive B is sold under the trademark COSMEDIA® Triple C (BASF Corporation). An exemplary product as Additive C is sold under the trademark RHEOCARE® HSP−1180 (BASF Corporation). An exemplary product as Additive D is sold under the trademark SALCARE® SC96 (BASF Corporation). An exemplary dispersion product as Additive E is sold under the trademark TINOVIS® CD (BASF Corporation). An exemplary product as Additive F is sold under the trademark LAMESOFT® TM BENZ (BASF Corporation). An exemplary product as Additive G is sold under the trademark PLANTASIL® Micro (BASF Corporation). An exemplary product as Additive H is sold under the name Advanced Moisture Complex W (BASF Corporation). These are exemplary commercial products and a chemical description of each product is also included in Table 1.
>50%
The functional additive may be added, sprayed, coated, brushed and/or other applied to a non-woven fabric in the form of a surface modifying composition. The surface modifying composition may consist of the functional additive and water, or may comprise additional compatible components. As used herein, a “compatible component” is a component that does not adversely affect application of the surface modifying composition to a non-woven fabric and does not adversely affect the improved tactile property contributed by the functional additive. The surface modifying composition may be substantially aqueous or may comprise a hydrophobic or oily component, such as an emulsion.
A surface modifying composition may comprise the functional additive in an amount ranging from about 0.05 wt % to about 2.0 wt. % or from about 0.1 wt. % to about 1.0 wt % of the functional additive. Exemplary wt. % ranges for each additive in a surface modifying composition are shown in Table 2. A surface modifying composition is typically aqueous. For functional additives that are water soluble, the surface modifying composition may be prepared by simple mixing. For functional additives that are partially or entirely insoluble in water, the surface modifying composition may be prepared using, for instance, heated water and a blending device sufficient to prepare an emulsion.
A surface modifying composition comprising a functional additive is applied to the non-woven surface in an amount sufficient to provide a suitable amount of additive in the resulting treated non-woven fabric to obtain an improved tactile property. Exemplary ranges of suitable amounts for the treated non-woven fabric for each functional additive are presented in Table 3. Suitable amounts are provided at wt. % functional additive relative to the weight of the dry untreated non-woven fabric. Alternatively, suitable amounts are also provided in wt. % functional additive relative to surface area of non-woven fabric. Exemplary suitable amounts are listed for each additive.
Blends of specific individual additives have also been discovered to improve a tactile property of a non-woven fabric. Blends may comprise the two additives in a ratio from 3:10 to 10:3. The ratio may be 1:1. The blends of individual additives shown in Table 4 are useful as functional additives for improving a tactile property of a non-woven fabric. Table 4 also includes an exemplary, but non-limiting, wt. % of the individual additive in a surface modifying composition, an exemplary, but non-limiting, suitable amounts for improving a tactile property.
A method of producing the treated non-woven fabric is also provided. In brief, a disclosed method comprises contacting a non-woven fabric with a surface modify composition comprising a functional additive. As described elsewhere herein, contacting a non-woven fabric surface may result in a surface coating; a surface coating including penetration within voids that might be present on the surface; partial impregnation within the thickness of the fabric; and complete impregnation through the thickness of the fabric. It is within the conventional skill of the artisan to control the contacting to obtain the desired embodiment. The functional additive may be added to the non-woven fabric by any method in the art. Conventional methods include, but are not limited to, spraying, brushing, dipping, rolling, and the like. The functional additive may be added to a non-woven fabric during the manufacture of the fabric, such as on an air-laid line or a spunlace line. Alternatively, the functional additive may be added to a non-woven fabric after it has been manufactured, or both during manufacture and after manufacture. The functional additive may be added to a manufactured product having a non-woven surface, after the manufacture of the product. Alternatively, the non-woven fabric may be treated with the surface modifying composition prior to manufacture of the non-woven product, or during the manufacture of the non-woven product, or any combination of before, during and after manufacture of the non-woven product.
Exemplary plastics for non-woven fabrics include, but are not limited to, polyester, polyolefins, and polyamides. Polypropylene and polyethylene are exemplary polyolefins. Polylactide is an exemplary polyester. Nylon is an exemplary polyamide.
Any product having a surface comprising a non-woven fabric that is intended to contact skin may comprise a functional additive of the disclosure. An exemplary product is a wipe such as household wipes, personal care wipes, and industrial wipes. Another exemplary non-woven product is a diaper. The core of a typical diaper is constructed of a topsheet that contacts the baby, an absorbent core, and a back-sheet intended to provide leakage protection. The topsheet may be a non-woven fabric such as a polypropylene non-woven fabric or polyethylene non-woven fabric. The surface of the topsheet intended to contact the baby skin may be treated with a surface modifying composition comprising a functional additive as described herein to improve a tactile property. Optionally, the back-sheet may also be treated with a surface modifying composition comprising a functional additive. The functional additive may be the same as that on the topsheet, or it may be different. The improved tactile property may improve the comfort of the baby. For instance, a softer and/or smoother surface may reduce skin irritation and other uncomfortable sensations.
The products, compositions and methods use are further described in detail by reference to the following experimental examples. These examples are provided for purposes of illustration only, and are not intended to be limiting unless otherwise specified. Thus, the products, compositions and methods of the disclosure should in no way be construed as being limited to the following examples, but rather, should be construed to encompass any and all variations which become evident as a result of the teaching provided herein.
Candidate selection: Twenty one commercial products were selected for experimentation as possible functional additives for non-woven products. The twenty one compositions (shown in Table 5) were identified as candidates based on the technical aspects and characteristics of the compositions to provide improved sensory/tactile properties in compositions for hair and skin applications. Parameters considered in identifying these twenty one compositions included composition ingredients, ratio of the ingredients, charge density, and molecular weight.
Brassica campestris
Helianthus Annuus
Argania Spinosa
Argania Spinosa
The candidate products were tested using the following procedure.
Candidate test solution preparation: The water solubility of each product was tested. Then, a solution or dispersion (hereinafter “test solution”) was prepared in water for each candidate composition. For water soluble candidates, the test solution was mixed for 5 minutes on a stir plate with a stir bar. For water insoluble or partially insoluble candidates, the test solution was prepared using heated water (˜60° C.) and was blended for 20 seconds with a homogenizer (Cuisinart® Hand Blender Model CSB-76) to prepare an aqueous dispersion. Additional blend time was added if the dispersion was not completely mixed after 20 seconds. For most candidates, the test solution prepared was generally a 1% solution prepared in, for instance, 100 ml of water or the amount of water needed to obtain a 1% solution. However, for some candidates, the test solution had a reduced percentage of candidate product because the viscosity of a 1% test solution was too high to permit a fine spray. Data on the physical state and solubility of the candidate product and the test solution concentrations prepared is in Table 6.
Candidate test sample preparation: Immediately after preparation of the test solutions, the test solution was loaded by spraying onto the hydrophilic face of a 4 inch×8 inch sample of an exemplary non-woven fabric as follows.
The exemplary non-woven fabric used in the study was manufactured by AVGOL Ltd. The non-woven fabric had the following specifications: Weight: 13.5 grams per square meter (gsm); Width: 20.00 cm; Length: 11,500 rmt; Roll Area: 2,300.00 sqmt; Customer Item No: 2005433; PR Date: May 1, 2010; Lot No. 23/10; and Shaft No. 1 Roll No. 3\13. The non-woven material was cut into 4 inch by 8 inch pieces using a paper cutter. The initial weight of each piece of non-woven fabric (“initial fabric sample weight”) was measured and recorded.
Each non-woven fabric sample was tested for hydrophilicity by pipetting a small droplet of water onto each side of the fabric sample. Once the hydrophilic face was determined for the fabric sample, the fabric sample was suspended using a binder clip and oriented so that the hydrophilic face of the sample was facing in the direction of the sprayer. A test solution was sprayed on the hydrophilic face of the sample using a Paasche Painter's Airbrush. The sprayed sample was then weighed to obtain the wet sample weight. Two duplicates were prepared for each test solution. Wet sample weights obtained ranged from 0.09 to 1.2 grams. The loading ratio of the combined weight of the test solution and the non-woven fabric sample to the weight of the dry non-woven fabric sample was maintained between 3 to 4 for all the samples prepared.
The wet treated non-woven samples were allowed to air dry overnight on a watch glass. Once dried, the final dry weight of each treated sample was taken. Each dried treated sample was stored in a closed plastic ZIPLOC bag. The amount of the test product applied to the non-woven fabric sample was recorded as weight percent of product:
Sensory data collection: The sensory perception evaluation of the treated non-woven fabric samples was carried out by a panel (three or four individuals). Sensory assessment was made in comparison to the untreated non-woven fabric. Assessments were done on the volar forearms. The volar forearm is the area of skin between the wrist and the elbow, on the palm side of the arm; this area of skin is highly sensitive. The volar forearm was contacted with the untreated or treated non-woven fabric sample by circular rubbing. In order to prevent the panelist from visually distinguishing between the treated and un-treated non-wovens, the panelists were asked not to look at the samples while evaluating therm Smoothness/softness were the sensory property that the panelist were asked to evaluate. Panelists were asked to rate each test sample from −1 to 1, with 0 being similar to control, −1 as exceptionally bad and +1 being exceptionally good relative to the control and −0.5 and +0.5 were used to distinguish between slightly bad and slightly good respectively relative to the control. The tests were performed at room temperature.
Statistics: To evaluate the sensory data, the medians for each parameter were calculated, as well as the average absolute deviation from the median as a measure of the variation of the individual values for each parameter. To calculate the statistical significance of a pair-wise calculation, the Wilcoxon test was carried out.
The weight percent product on the non-woven sample data and sensory data for the 21 candidate products are summarized in Table 7.
The statistical analyses of the data in Table 7 are depicted in the chart in the FIGURE. In the chart, the position of the symbol indicates the median. The average absolute deviation from the median is transformed into the weighted deviation from the median and is shown in the chart in the form of shifted lines.
The data indicate that the majority of the candidate products did not improve the tactile property of the non-woven fabric or made the tactile properties worse, compared to the untreated non-woven fabric. These results are surprising because all of the candidate products were selected in part due to their known function to improve tactile properties in hair and skin applications. The candidates that improved the tactile property of the non-woven fabric were: C1 (COSMEDIA® SP), C2 (COSMEDIA® Triple C), C5 (RHEOCARE® HSP−1180), C6 (SALCARE® SC96), C7 (TINOVIS® CD), 010 (LAMESOFT® TM BENZ), and C20 (Advanced Moisture Complex W) Although the median score for candidate C13 (PLANTASIL® Micro) was 0, the weighted deviation suggests that this composition also can improve the tactile property of the non-woven fabric. In some cases, the improvement in tactile property was observed only at one of two weight percent product tested. Specifically, COSMEDIA® SP improved the softness/smoothness at 0.18 wt. %; COSMEDIA® Triple C at 0.81 wt. %; TINOVIS® CD at 0.77 wt. %, LAMESOFT® TM BENZ at 2.1 wt. %; PLANTASIL® Micro at 2.66 wt. %; and Advanced Moisture Complex W at 1.88 wt. %. RHEOCARE® HSP-1180 improved the tactile property at 0.66 wt. % and 0.73 wt. %, and SALCARE® SC96 improved the tactile property of the non-woven fabric at 0.94 wt. % and 0.82 wt. %.
A series of blends of a subset of the candidate products were also prepared. Test solutions of blends were prepared by simple mixing using a stir bar and stir plate. For each test solution blend shown in Table 8, the first candidate product was mixed in water, then the second product was added to obtain the desired wt. % of each in the final blend. For instance, blend B1 was prepared by mixing candidate C13 in water, then adding candidate 010, in appropriate quantities to obtain a test solution blend consisting of 0.5 wt C13 and 0.5 wt. % C10. A summary of the blends and the data regarding the treated fabric samples prepared are shown in Table 8.
Non-woven fabric samples treated with the series of test solution blends were prepared and tested by a panel of two individuals. The sensory data for the blends are summarized in Table 9.
The data demonstrate that only three of the blends improved a tactile property of the non-woven fabric. The three blends were B1, B2 and B5. All three of these blends included candidate C13 (LAMESOFT® TM BENZ).
Additional duplicates of treated non-woven fabric samples of some of the candidate products and blends were prepared for testing by two additional panelists. The candidate products were: C2, C6, C7, C10, C13, and C20. The blends were B1, B2, and B5. The sensory testing was performed using a scale of 1 to 5 where 5 is the most pleasant. The two panelists were asked to rank samples on tactile properties as well as other performance parameters typically tested for diapers. The hydrophobicity/hydrophilicity of the treated non-woven samples was also assessed using a de-ionic water drop penetration test for chemical coating on a non-woven sheet (n=3 drops). In brief, a drop of deionized water is allowed to fall from a height of about 1 cm onto the sample surface. If the water drop stays on the non-woven sample surface for more than 10 seconds, the surface is deemed hydrophobic. If the water drop stays on the non-woven sample surface for less than 3 seconds, the surface is deemed hydrophilic. If the drop stays on the non-woven surface for greater than 3 seconds and less than 10 seconds, it is deemed hesitated. The water surface tension is about 72 dyne/cm at room temperature. The data are presented in Table 10.
Both panelists commented that that non-woven fabric sample treated with Additive C2 was by far the best feeling of the 9 samples evaluated.
The disclosures of each and every patent, patent application, and publication cited herein are hereby incorporated herein by reference in their entirety for all purposes.
While the products, methods of making them, and their methods of use have been disclosed with reference to specific embodiments, it is apparent that other embodiments and variations may be devised by others skilled in the art without departing from the true spirit and scope of the described products and methods. The appended claims are intended to be construed to include all such embodiments and equivalent variations.
The benefit of the filing date of U.S. Provisional Patent Application No. 61/659,879, filed Jun. 14, 2012 is hereby claimed. The entire disclosure of the aforesaid application is incorporated herein in its entirety by reference.
| Number | Date | Country | |
|---|---|---|---|
| 61659879 | Jun 2012 | US |
