Water-soluble non-woven composite structure

Abstract

The invention relates to a water soluble nonwoven composite structure. Provided herein is a nonwoven composite article comprising: a first layer comprising a first nonwoven fabric, the first nonwoven fabric comprising a first plurality of fibers having a first diameter; comprising a second nonwoven fabric comprising a second plurality of fibers having a second diameter; and a first interface comprising at least a portion of the first nonwoven fabric and at least a portion of the second nonwoven fabric, where the portion of the first nonwoven fabric and the portion of the second nonwoven fabric are fused together, and where the second diameter is less than the first diameter, and the first plurality of fibers, the second plurality of fibers, or both comprise a water-soluble polyvinyl alcohol fiber forming material. Also provided are flushable tissues and absorbent articles comprising a non-woven fabric comprising fibers comprising a water-soluble polyvinyl alcohol fiber forming material.

Description

[0001] This application is a divisional application of the invention patent application with application date of September 30, 2020, application number 202080069010.4, and invention name “Water-soluble non-woven composite material structure”.

[0002] CROSS-REFERENCE TO RELATED APPLICATIONS

[0003] This application claims the benefit of U.S. Provisional Patent Application No. 62 / 908,310, filed on September 30, 2019, under 35 U.S.C. §119(e), the entire contents of which are incorporated herein by reference. Technical Field

[0004] The present disclosure relates generally to nonwoven composite structures, flushable tissues, and absorbent articles. More specifically, the present disclosure relates to nonwoven composite materials including water-soluble fibers including polyvinyl alcohol fiber-forming materials. Background Art

[0005] Nonwoven fabrics are traditionally used in a variety of disposable consumer products, including personal care products, such as diaper ingredients, feminine care and adult incontinence products, and disposable tissues, such as industrial applications, medical applications, cleaning applications and personal / baby care products. Traditional chemical materials used in such products, such as rayon, polypropylene or cotton fibers, are usually non-durable, non-biodegradable, potentially produce microplastics, and are often improperly disposed of, such as flushed down the toilet and enter wastewater treatment and sewage facilities. Known tissues must be discarded in trash cans, which may be unhygienic or inconvenient for users. Improper disposal of these articles can cause pipe blockages in the home, cause the formation of "fat balls" or clots of biodegradable and non-biodegradable materials (composed of condensed grease and cooking fat and disposable tissues) in residential and municipal wastewater systems, cause marine microplastics, and require changes in consumer behavior.

[0006] It is therefore advantageous to provide a nonwoven structure using a chemical material that is relatively biodegradable, does not generate microplastics, is even soluble in water, has mechanical properties suitable for withstanding the stresses applied to disposable consumer products (e.g. rubbing a tissue or moving a child wearing a diaper) and has a liquid storage chamber in order to, for example, load lotion onto the tissue and / or retain liquid on a collection layer. Summary of the invention

[0007] One aspect of the present disclosure provides a nonwoven composite article having: a first layer of a first nonwoven fabric, the first nonwoven fabric comprising a first plurality of fibers having a first diameter; a second layer of a second nonwoven fabric, the second nonwoven fabric comprising a second plurality of fibers having a second diameter; and a first interface comprising at least a portion of the first nonwoven fabric and at least a portion of the second nonwoven fabric, wherein the portion of the first nonwoven fabric and the portion of the second nonwoven fabric are fused together, and wherein the second diameter is less than the first diameter, and the first plurality of fibers, the second plurality of fibers, or both comprise a water-soluble polyvinyl alcohol fiber-forming material.

[0008] Another aspect of the present disclosure provides a wearable absorbent article comprising an absorbent core having a side facing the wearer and a side facing the outside; and a liquid collection layer, wherein the liquid collection layer comprises a non-woven fabric, the non-woven fabric comprising a plurality of fibers comprising a water-soluble polyvinyl alcohol fiber-forming material.

[0009] Another aspect of the present disclosure provides an absorbent article comprising a liquid permeable topsheet, a liquid impermeable backsheet, an absorbent core, and a liquid acquisition layer comprising a nonwoven fabric including a plurality of fibers comprising a water-soluble polyvinyl alcohol fiber-forming material.

[0010] Another aspect of the present disclosure provides a flushable wet wipe comprising the nonwoven composite article of the present disclosure.

[0011] Another aspect of the present disclosure provides use of the composite article of the present disclosure for flushable wipes.

[0012] Another aspect of the present disclosure provides use of the composite article of the present disclosure in a wearable absorbent article.

[0013] Another aspect of the present disclosure provides a method of forming a composite article of the present disclosure, the method comprising depositing a second layer comprising a second nonwoven fabric on a first layer comprising a first nonwoven fabric under conditions sufficient to fuse at least the portion of the first nonwoven fabric with the portion of the second nonwoven fabric, thereby forming a first interface.

[0014] Another aspect of the present disclosure provides a liquid-containing nonwoven article, the liquid-containing nonwoven article comprising: a core nonwoven fabric, the core nonwoven fabric comprising a first plurality of fibers containing a first polyvinyl alcohol fiber-forming material, wherein the core nonwoven fabric contains a liquid, and the liquid contains an active agent; and an outer nonwoven fabric, the outer nonwoven fabric comprising a second plurality of fibers containing a second polyvinyl alcohol fiber-forming material, wherein the outer nonwoven fabric encloses the core nonwoven fabric.

[0015] Another aspect of the present disclosure provides a method of forming the liquid-containing nonwoven article of the present disclosure, the method comprising contacting a core nonwoven fabric with a liquid containing an active agent, encapsulating the core nonwoven fabric with an outer nonwoven fabric, and sealing the outer nonwoven fabric enclosing the core nonwoven fabric.

[0016] For the compositions described herein, optional features that can be selected from various aspects and embodiments provided herein are contemplated, including but not limited to, ingredients and composition ranges, fiber-forming materials, fiber diameter ranges, various layer configurations, fiber geometries, and / or mechanical properties thereof.

[0017] Other aspects and advantages will become apparent to those skilled in the art by reviewing the following detailed description. Although the composite structures, flushable tissues, and absorbent articles of the present disclosure may take different forms of embodiments, the following description includes specific embodiments, with the understanding that the disclosure is illustrative and is not intended to be limited to the specific embodiments described herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] To further facilitate understanding of the present disclosure, three drawings are attached.

[0019] Figure 1 Cross sections of different fiber shapes are shown, with the straight lines representing the fiber diameter.

[0020] Figure 2 is a diagram of a nonwoven fabric, which indicates the outer surfaces of the fabric, such as 100 and 101.

[0021] Figure 3 An interface 200 is shown where a first nonwoven textile 201 overlaps a second nonwoven textile 202 .

[0022] Figure 4A is an illustration of a nonwoven fabric indicating a machine direction 301 and a cross direction 300 and including a second nonwoven fabric 302 having the same length as the nonwoven fabric in the machine direction 301 .

[0023] Figure 4B It is a diagram showing a nonwoven fabric wrapped around a second nonwoven fabric 302 along a machine direction 301 .

[0024] Figure 5A is an illustration of a nonwoven fabric wrapped around and enclosing a second nonwoven fabric (not shown) having sealed portions 303 at multiple points along the machine direction and along the transverse edges 304 .

[0025] Figure 5B is an illustration of a nonwoven fabric wrapped around and enclosing a second nonwoven fabric (not shown) having sealed portions 303 at multiple points along the machine direction and having been cut 305 to form unit doses 306 having flanges 307 .

[0026] Figure 6 is a diagrammatic representation of one method of folding a nonwoven fabric.

[0027] Figure 7 is a diagrammatic representation of one method of folding a nonwoven fabric.

[0028] Figure 8 Multiple views showing the configuration for horizontal wicking testing.

[0029] Fig.9A is a graph of the Washburn Slope of the fabrics of the present disclosure as a function of the average degree of hydrolysis of the polyvinyl alcohol fiber-forming material in the fabrics.

[0030] Fig. 9B is a graph of the wicking rate of nonwoven fabrics of the present disclosure as a function of the average degree of hydrolysis of the polyvinyl alcohol fiber-forming material in the fabric.

[0031] Fig. 9C is a graph of the absorbency rate of nonwoven fabrics of the present disclosure as a function of the average degree of hydrolysis of the polyvinyl alcohol fiber-forming material in the fabric.

[0032] Fig.10 is an interval graph of the liquid absorption capacity of the nonwoven fabrics of the present disclosure as a function of the average degree of hydrolysis of the polyvinyl alcohol fiber-forming material in the fabric.

[0033] Fig.11A is a graph of the Wassbond slope of the nonwoven fabrics of the present disclosure as a function of the average degree of hydrolysis of the polyvinyl alcohol fiber-forming material in the multi-layer article.

[0034] Fig. 11B is a graph of the wicking rate of nonwoven fabrics of the present disclosure as a function of the average degree of hydrolysis of the polyvinyl alcohol fiber-forming material in the multi-layer article.

[0035] Fig. 11C is a graph of the absorbent rate of nonwoven fabrics of the present disclosure as a function of the average degree of hydrolysis of the polyvinyl alcohol fiber-forming material in the multi-layer article.

[0036] Fig.12 is an interval graph of the liquid absorbent capacity of the nonwoven fabrics of the present disclosure as a function of the average degree of hydrolysis of the polyvinyl alcohol fiber-forming material in the multi-layer article.

[0037] Fig.13A is a graph of the Wassbond slope of the nonwoven fabrics of the present disclosure as a function of the average degree of hydrolysis of the polyvinyl alcohol fiber-forming material in the multi-layer article.

[0038] Fig. 13Bis a graph of the wicking rate of nonwoven fabrics of the present disclosure as a function of the average degree of hydrolysis of the polyvinyl alcohol fiber-forming material in the multi-layer article.

[0039] Fig. 13C is a graph of the absorbent rate of nonwoven fabrics of the present disclosure as a function of the average degree of hydrolysis of the polyvinyl alcohol fiber-forming material in the multi-layer article.

[0040] Fig.14 is an interval graph of the liquid absorbent capacity of the nonwoven fabrics of the present disclosure as a function of the average degree of hydrolysis of the polyvinyl alcohol fiber-forming material in the multi-layer article. DETAILED DESCRIPTION

[0041] The present disclosure provides nonwoven composite articles, flushable tissues, absorbent articles, nonwoven articles containing liquids, and methods of making and using the same. The nonwoven composite articles of the present disclosure include: a first layer including a first nonwoven fabric, the first nonwoven fabric including a first plurality of fibers having a first diameter; a second layer including a second nonwoven fabric, the second nonwoven fabric including a second plurality of fibers having a second diameter; and a first interface including at least a portion of the first nonwoven fabric and at least a portion of the second nonwoven fabric, wherein the portion of the first nonwoven fabric and the portion of the second nonwoven fabric are fused together, and wherein the second diameter is less than the first diameter, and the first plurality of fibers, the second plurality of fibers, or both contain water-soluble polyvinyl alcohol fiber-forming material.

[0042] The nonwoven composite articles of the present disclosure may provide one or more advantages, including, but not limited to, improved liquid acquisition relative to single-layer nonwoven articles, improved lotion loading and retention relative to single-layer nonwoven articles, improved biodegradability relative to conventional nonwoven articles, improved flushability relative to conventional nonwoven articles, improved softness relative to conventional nonwoven articles, improved mechanical properties (e.g., modulus, tensile strength, elongation, tenacity, and / or breaking strength) relative to single-layer carded nonwoven fabrics comprising the same water-soluble fibers, and / or improved dispersibility and solubility relative to conventional nonwoven articles. The flushable tissues of the present disclosure may provide one or more advantages, including, but not limited to, improved lotion loading and retention relative to conventional tissues, improved liquid acquisition relative to conventional tissues, improved softness relative to conventional tissues, improved flushability relative to conventional tissues, and / or improved biodegradability, dispersibility, and / or solubility relative to conventional tissues. The absorbent articles of the present disclosure may provide one or more advantages including, but not limited to, improved liquid acquisition relative to conventional collection layers of absorbent articles, improved liquid retention relative to conventional collection layers of absorbent articles, improved softness relative to conventional collection layers, and / or improved biodegradability, dispersibility and / or solubility relative to conventional paper towels.

[0043] As used herein and unless otherwise specified, the term "nonwoven fabric" refers to a fabric or sheet comprising fibers that are arranged (e.g., by a carding process) and bonded to each other, consisting of the fibers or consisting essentially of the fibers. In addition, as used herein, "nonwoven fabric" includes any structure, including nonwoven fabrics or sheets, including, for example, nonwoven fabrics or sheets with a film laminated on the surface. The method for preparing nonwoven fabrics from fibers is well known in the art, such as the Nonwoven Fabrics Handbook compiled by Ian Butler and edited by Subhash Batra et al., Printing by Design, 1999, described in the document, which is incorporated herein by reference in its entirety. As used herein and unless otherwise specified, the term "film" refers to a continuous film or sheet, such as prepared by a casting or extrusion process.

[0044] As used herein and unless otherwise specified, the term "water-soluble" refers to any fiber, nonwoven fabric, nonwoven composite material article or film having a dissolution time of 300 seconds or less at a specified temperature as determined according to MSTM-205, as described herein. For example, at a temperature of about 80°C, about 70°C, about 60°C, about 50°C, about 40°C, about 20°C, or about 10°C, the dissolution time may optionally be 200 seconds or less, 100 seconds or less, 60 seconds or less, or 30 seconds or less. In an embodiment where the dissolution temperature is not specified, the water-soluble fiber, nonwoven fabric, or nonwoven composite material article has a dissolution time of 300 seconds or less at a temperature of not more than about 80°C. As used herein and unless otherwise specified, the term "cold water soluble" refers to any fiber, nonwoven fabric, or nonwoven composite material article having a dissolution time of 300 seconds or less at 10°C as determined according to MSTM-205. For example, at 10°C, the dissolution time can optionally be 200 seconds or less, 100 seconds or less, 60 seconds or less, or 30 seconds. In an embodiment, "water-soluble film" means that the film dissolves in 300 seconds or less at a temperature of no more than 80°C at a thickness of 1.5 mils. For example, a water-soluble film of 1.5 mils (about 38 μm) thickness may have a dissolution time of 300 seconds or less, 200 seconds or less, 100 seconds or less, 60 seconds or less, 30 seconds or less, or 20 seconds or less at a temperature of about 70°C, about 60°C, about 50°C, about 40°C, about 30°C, about 20°C, or about 10°C.

[0045] As used herein, "comprising" refers to various components, ingredients, or steps that can be used together in practicing the present disclosure. Thus, the term "comprising" encompasses the more restrictive terms "consisting essentially of" and "consisting of." The present compositions may comprise, consist essentially of, or consist of any of the required and optional ingredients disclosed herein. The invention illustratively disclosed herein can be suitably practiced in the absence of any ingredient or step not specifically disclosed herein.

[0046] All percentages, parts and ratios referred to herein are based on the total dry weight of the fibers, nonwoven fabrics, nonwoven composite articles, flushable tissues or absorbent articles of the present disclosure, as the case may be, and unless otherwise specified, all measurements are made at about 25° C. All such weights as they pertain to listed ingredients are based on the active level, and, therefore, do not include carriers or by-products that may be included in commercially available materials, unless otherwise specified.

[0047] All ranges set forth herein include all possible subsets of ranges and any combination of such subset ranges. Unless otherwise stated, the default range includes the endpoints. In the case of providing a range of values, it should be understood that each intermediate value between the upper and lower limits of that range and any other described value or intermediate value in that described range are included in the present disclosure. The upper and lower limits of these smaller ranges can be independently included in a smaller range, and are also included in the present disclosure, subject to any specific exclusion limits in the described range. In the case where the described range includes one or two of the limits, it is also considered that the scope not including any one or two of those contained limits is also a part of the present disclosure.

[0048] It is expressly contemplated that for any numerical value described herein, for example as a parameter of the subject matter or as part of a range related to the subject matter, an alternative portion forming part of the description is a functionally equivalent range around the specific numerical value (e.g., when a dimension is disclosed as "40 mm," an alternative embodiment "about 40 mm" is contemplated). Likewise, a value described as "about" expressly includes the specific value itself as an alternative embodiment (e.g., when an endpoint is described as "about 40," an alternative embodiment "40" is contemplated.

[0049] As used herein and unless otherwise specified, the terms "wt. %" and "wt %" refer to the composition ("dry" (water-free) weight parts) of the identified ingredient in the entire fiber, nonwoven fabric, nonwoven composite article, flushable tissue, or absorbent article.

[0050] As used herein and unless otherwise specified, the term "PHR" ("phr") means the composition (parts per hundred parts of polymer resin or parts per hundred parts of fiber-forming material (whether PVOH or other polymer resin)) of an identified ingredient in a water-soluble fiber, nonwoven fabric, nonwoven composite article, flushable tissue, or absorbent article.

[0051] Fiber forming materials

[0052] In general, the fibers of the present disclosure may include a single fiber-forming material or a combination of fiber-forming materials (i.e., a blend). A single fiber may include one or more water-soluble fiber-forming materials, one or more water-insoluble fiber-forming materials, or a combination of water-soluble fiber-forming materials and water-insoluble fiber-forming materials. The fibers of the present disclosure may generally include synthetic fiber-forming materials, natural fiber-forming materials, plant-based fiber-forming materials, bio-based fiber-forming materials, biodegradable fiber-forming materials, compostable fiber-forming materials, or a combination thereof. Plant-based fiber-forming materials may be naturally occurring (e.g., cotton) or reconstituted (e.g., bamboo).

[0053] Water-soluble fiber forming material

[0054] Generally, the water-soluble fiber-forming material can be a water-soluble polymer. The water-soluble polymer can include, but is not limited to, polyvinyl alcohol, polyacrylate, water-soluble acrylate copolymer, polyvinyl pyrrolidone, polyethylene imine, pullulan, water-soluble natural polymers (including, but not limited to, guar gum, gum arabic, gum ternary, carrageenan, and water-soluble starch), water-soluble polymer derivatives (including, but not limited to, modified starch, ethoxylated starch, and hydroxypropylated starch), copolymers of the above, and combinations of any of the above. Other water-soluble polymers can include polyalkylene oxides, polyacrylamides, polyacrylic acids and salts thereof, water-soluble cellulose, cellulose ethers, cellulose esters, cellulose amides, polyvinyl acetates, polycarboxylic acids and salts thereof, polyamino acids, polyamides, gelatin, methylcellulose, carboxymethylcellulose and salts thereof, dextrin, ethylcellulose, hydroxyethylcellulose, hydroxypropylmethylcellulose, maltodextrin, polymethacrylates, and combinations of any of the above. Such water-soluble polymers (whether PVOH or other) can be purchased from a variety of sources.

[0055] In an embodiment, the water-soluble fiber-forming material comprises polyvinyl alcohol, polyacrylate, polyvinyl pyrrolidone, polyethylene imine, guar gum, gum arabic, tannin gum, carrageenan, water-soluble starch, water-soluble cellulose, cellulose ether, cellulose ester, cellulose amide, or a combination thereof. In an embodiment, the water-soluble fiber-forming material comprises polyacrylate, polyvinyl pyrrolidone, polyethylene imine, guar gum, gum arabic, tannin gum, carrageenan, water-soluble starch, water-soluble cellulose, cellulose ether, cellulose ester, cellulose amide, or a combination thereof.

[0056] Polyvinyl alcohol is a synthetic polymer that is typically prepared from polyvinyl acetate by alcoholysis (commonly referred to as hydrolysis or saponification). Fully hydrolyzed PVOH, in which nearly all acetate groups have been converted to alcohol groups, is a strongly hydrogen-bonded, highly crystalline polymer that is soluble only in hot water greater than about 140°F (about 60°C). If a sufficient number of acetate groups are allowed to remain after the polyvinyl acetate is hydrolyzed (i.e., the PVOH polymer is partially hydrolyzed), the polymer has weaker hydrogen bonds, lower crystallinity, and is generally soluble in cold water below about 50°F (about 10°C). Thus, the partially hydrolyzed polymer is a vinyl alcohol-vinyl acetate copolymer, i.e., a PVOH copolymer, but is commonly referred to as PVOH.

[0057] In some embodiments, polyvinyl alcohol includes modified polyvinyl alcohol, such as copolymer. Modified polyvinyl alcohol may include copolymer or higher polymer (such as terpolymer), which includes one or more monomers except vinyl acetate / vinyl alcohol group. Optionally, modification is neutral, such as provided by ethylene, propylene, N-vinyl pyrrolidone or other uncharged monomer substances. Optionally, modification is cationic modification, such as provided by positively charged monomer substances. Optionally, modification is anionic modification, such as provided by negatively charged monomer substances. Therefore, in some embodiments, polyvinyl alcohol includes anion-modified polyvinyl alcohol. Anion-modified polyvinyl alcohol may include partially or completely hydrolyzed PVOH copolymers, which include anionic monomer units, vinyl alcohol monomer units and optionally present vinyl acetate monomer units (that is, when hydrolysis is incomplete). In some embodiments, PVOH copolymers may include two or more types of anionic monomer units. The general class of anionic monomer units that can be used in the PVOH copolymer includes vinyl polymerized units corresponding to sulfonic acid vinyl monomers and their esters, monocarboxylic acid vinyl monomers, their esters and anhydrides, dicarboxylic acid monomers having polymerizable double bonds, their esters and anhydrides, and alkali metal salts of any of the foregoing. Suitable examples of anionic monomer units include vinyl polymerized units corresponding to vinyl anionic monomers including vinyl acetic acid, maleic acid, maleic acid monoalkyl esters, maleic acid dialkyl esters, maleic anhydride, fumaric acid, fumaric acid monoalkyl esters, fumaric acid dialkyl esters, itaconic acid, itaconic acid monoalkyl esters, itaconic acid dialkyl esters, citraconic acid, citraconic acid monoalkyl esters, citraconic acid dialkyl esters, citraconic anhydride, mesaconic acid, mesaconic acid monoalkyl esters, mesaconic acid dialkyl esters, glutaconic acid, glutaconic acid monoalkyl esters, glutaconic acid dialkyl esters, glutaconic anhydride, acrylic acid alkyl esters. Esters, (alkyl) acrylates, vinyl sulfonic acid, allyl sulfonic acid, ethanedisulfonic acid, 2-acrylamido-1-methylpropane sulfonic acid, 2-acrylamido-2-methylpropane sulfonic acid, 2-methacrylamido-2-methylpropane sulfonic acid, 2-sulfoethyl acrylate, alkali metal salts (e.g., sodium, potassium or other alkali metal salts) thereof, esters (e.g., methyl esters, ethyl esters or other C1-C4 or C6 alkyl esters) thereof, and combinations thereof (e.g., multiple types of anionic monomers, or equivalent forms of the same anionic monomers). In some embodiments, the PVOH copolymer may include two or more types of monomer units selected from neutral, anionic and cationic monomer units.

[0058] The extent to which one or more anionic monomer units are incorporated into the PVOH copolymer is not particularly limited. In an embodiment, the amount of one or more anionic monomer units present in the PVOH copolymer is in the range of about 1 mol% or 2 mol% to about 6 mol% or 10 mol% (e.g., at least 1.0, 1.5, 2.0, 2.5, 3.0, 3.5 or 4.0 mol% and / or at most about 3.0, 4.0, 4.5, 5.0, 6.0, 8.0 or 10 mol%).

[0059] Polyvinyl alcohol can undergo changes in solubility characteristics. It is known to those skilled in the art that the acetate groups in copoly(vinyl acetate vinyl alcohol) polymers (PVOH homopolymers) can be hydrolyzed by either acid or base hydrolysis. As the degree of hydrolysis increases, polymer compositions made from PVOH homopolymers will have increased mechanical strength, but reduced solubility at lower temperatures (e.g., hot water temperatures necessary to achieve complete dissolution). Thus, exposure of PVOH homopolymers to alkaline environments (e.g., caused by clothing bleach additives) can convert the polymer from one that dissolves quickly and completely in a given aqueous environment (e.g., a cold water medium) to one that dissolves slowly and / or incompletely in an aqueous environment, potentially resulting in undissolved polymer residues at the end of a wash cycle.

[0060] PVOH copolymers with pendant carboxyl groups, such as vinyl alcohol / hydrolyzed sodium methyl acrylate polymers, can form lactone rings between adjacent pendant carboxyl and alcohol groups, thereby reducing the water solubility of the PVOH copolymer. In the presence of a strong base, the lactone ring can open (e.g., via a lactone ring-opening reaction, forming pendant carboxyl and alcohol groups and increasing water solubility) within a few weeks under relatively warm (ambient) and high humidity conditions. Therefore, in contrast to the effect observed in the presence of PVOH homopolymer, such PVOH copolymers are believed to become more soluble during storage due to chemical interactions between the polymer and the alkaline composition within the bag. Therefore, as it ages, the bag may become increasingly susceptible to premature dissolution during a hot wash cycle (nominal 40°C), and may in turn reduce the efficacy of certain laundry actives due to the presence of bleach and the resulting decrease in pH.

[0061] Specific sulfonic acids and derivatives thereof having polymerizable ethylene bonds can be copolymerized with vinyl acetate to obtain cold-water soluble PVOH polymers that are stable in the presence of strong bases. The base-catalyzed alcoholysis products of these copolymers used in water-soluble fiber formulations are rapidly soluble vinyl alcohol-sulfonate copolymers. The sulfonate groups in the PVOH copolymers can be restored to sulfonic acid groups in the presence of hydrogen ions, but the sulfonic acid groups still allow the polymer to achieve excellent cold-water solubility. In an embodiment, the vinyl alcohol-sulfonate copolymer does not contain residual acetate groups (i.e., completely hydrolyzed) and therefore will not be hydrolyzed by acid or alkaline hydrolysis.

[0062] Generally, water solubility increases with increasing amounts of modification, so that sufficient modification via the sulfonate or sulfonic acid groups inhibits hydrogen bonding and crystallinity, thereby enabling dissolution in cold water. The copolymers are generally unaffected in the presence of acidic or basic materials, except for the sulfonate or sulfonic acid groups, which maintain excellent cold water solubility even in the presence of acidic or basic materials. Examples of suitable sulfonic acid comonomers (and / or their alkali metal salt derivatives) include vinyl sulfonic acid, allyl sulfonic acid, ethanedisulfonic acid, 2-acrylamido-1-methylpropanesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 2-methacrylamido-2-methylpropanesulfonic acid, and 2-sulfoethyl acrylate, with the preferred comonomer being the sodium salt of 2-acrylamido-2-methylpropanesulfonic acid (AMPS).

[0063] A water-soluble polymer (whether a polyvinyl alcohol polymer or other) may be blended. When the polymer blend includes a polyvinyl alcohol polymer blend, the PVOH polymer blend may include: a first PVOH polymer ("first PVOH polymer"), which may include a PVOH homopolymer or PVOH copolymer (e.g., a PVOH terpolymer (or higher copolymer)) containing one or more types of anionic monomer units; and a second PVOH polymer ("second PVOH polymer"), which may include a PVOH homopolymer or PVOH copolymer (e.g., a PVOH terpolymer (or higher copolymer)) containing one or more types of anionic monomer units. In some aspects, the PVOH polymer blend includes only the first PVOH polymer and the second PVOH polymer (e.g., a binary blend of the two polymers). Alternatively or additionally, the PVOH polymer blend or the fiber or nonwoven fabric made therefrom may be characterized by being free of or substantially free of other polymers (e.g., typically other water-soluble polymers, especially other polymers based on PVOH, or both). As used herein, "substantially free" means that the first and second PVOH polymers account for at least 95 wt.%, at least 97 wt.%, or at least 99 wt.% of the total amount of water-soluble polymers in the water-soluble fiber or film. In other aspects, the water-soluble fiber or nonwoven fabric may include one or more additional water-soluble polymers. For example, the PVOH polymer blend may include a third PVOH polymer, a fourth PVOH polymer, a fifth PVOH polymer, etc. (e.g., one or more additional PVOH homopolymers or PVOH copolymers with or without anionic monomer units). For example, the water-soluble fiber or nonwoven fabric may include at least a third (or fourth, fifth, etc.) water-soluble polymer in addition to the PVOH polymer (e.g., in addition to the PVOH homopolymer or PVOH copolymer with or without anionic monomer units).

[0064] The degree of hydrolysis (DH) of the PVOH homopolymer and PVOH copolymer included in the water-soluble fibers and nonwoven fabrics of the present disclosure can range from about 75% to about 99.9% (e.g., from about 79% to about 92%, from about 80% to about 90%, from about 88% to 92%, from about 86.5% to about 89%, or about 88%, 90% or 92%, for example, for cold water soluble compositions; from about 90% to about 99%, from about 92% to about 99%, from about 95% to about 99%, from about 98% to about 99%, from about 98% to about 99.9%, from about 96%, from about 98%, from about 99% or greater than 99%). As the degree of hydrolysis decreases, the mechanical strength of the fiber or film made from the polymer decreases at temperatures below about 20° C., but it dissolves faster. As the degree of hydrolysis increases, the fiber or film made from the polymer tends to have stronger mechanical strength, and the thermoforming ability tends to decrease. The degree of hydrolysis of the PVOH can be selected so that the water solubility of the polymer is temperature-dependent and thus also affects the solubility of the fiber or film made from the polymer and additional ingredients. In one option, the fiber or film has cold water solubility. For (vinyl acetate vinyl alcohol) copolymers that do not include any other monomers (e.g., homopolymers that are not copolymerized with anionic monomers), cold water soluble fibers or films that are soluble in water at a temperature of less than 10°C may include PVOH with a degree of hydrolysis in the range of about 75% to about 90%, or in the range of about 80% to about 90%, or in the range of about 85% to about 90%. In another option, the fiber or film has hot water solubility. For (vinyl acetate vinyl alcohol) copolymers that do not include any other monomers (e.g., homopolymers that are not copolymerized with anionic monomers), hot water soluble fibers or films that are soluble in water at a temperature of at least about 60°C may include PVOH with a degree of hydrolysis of at least about 98%.

[0065] The degree of hydrolysis of the polymer blend can also be calculated by the arithmetic weighted average degree of hydrolysis For example, a PVOH polymer comprising two or more PVOH polymers It is based on the formula Calculate, where W i is the weight percentage of the corresponding PVOH polymer and H i When a polymer is referred to as having a particular degree of hydrolysis, the polymer may be a single polyvinyl alcohol polymer having the specified degree of hydrolysis or a blend of polyvinyl alcohol polymers having a specified average degree of hydrolysis.

[0066] The viscosity (μ) of the PVOH polymer is determined by measuring fresh solutions as described in Annex E Brookfield Test Method, British Standard EN ISO 15023-2:2006, using a Brookfield LV viscometer with a UL adapter. The international convention is to state the viscosity of a 4% aqueous solution of polyvinyl alcohol at 20°C. Unless otherwise specified, all viscosities expressed in centipoise (cp) herein are to be understood to refer to the viscosity of a 4% aqueous solution of polyvinyl alcohol at 20°C. Similarly, when a polymer is described as having (or not having) a specific viscosity, unless otherwise specified, it is meant that the specified viscosity is the average viscosity of the polymer, which inherently has a corresponding molecular weight distribution, i.e., the weighted natural logarithmic average viscosity as described below. It is well known in the art that the viscosity of a PVOH polymer is related to the weight average molecular weight of the PVOH polymer. is related, and the viscosity is often used as Representative.

[0067] For reference, in the polymer blend, the first PVOH polymer is represented as having a first 4% solution viscosity (μ1) at 20° C., and the second PVOH polymer is represented as having a second 4% solution viscosity (μ2) at 20° C. In various embodiments, the first viscosity μ1 can be in the range of about 4 cP to about 70 cP (e.g., at least about 4, 8, 10, 12, or 16 cP and / or up to about 12, 16, 20, 24, 28, 30, 32, 35, 37, 40, 45, 48, 50, 56, 60, or 70 cP, such as about 4 cP to about 70 cP, about 4 cP to about 60 cP, about 4 cP to about 46 cP, about 4 cP to about 24 cP, about 10 cP to about 16 cP, or about 10 cP to about 20 cP, or about 20 cP to about 30 cP). Alternatively or additionally, the second viscosity μ2 can be in the range of about 4 cP to about 70 cP (e.g., at least about 4, 8, 10, 12, or 16 cP and / or up to about 12, 16, 20, 24, 28, 30, 32, 35, 37, 40, 45, 48, 50, 56, 60, or 70 cP, such as about 12 cP to about 30 cP, about 10 cP to about 16 cP, or about 10 cP to about 20 cP, or about 20 cP to about 30 cP). When the PVOH polymer blend includes three or more PVOH polymers selected from PVOH polymers and PVOH copolymers, the above viscosity values ​​can be applied individually to each PVOH polymer or PVOH copolymer. Thus, the weight average molecular weight of the water-soluble polymer (including the first PVOH copolymer and the second PVOH copolymer) can be, for example, in the range of about 30,000 to about 175,000, or about 30,000 to about 100,000, or about 55,000 to about 80,000. When referring to the average viscosity of the PVOH polymer blend, the weighted natural logarithmic average viscosity is used. PVOH polymers comprising two or more PVOH polymers It is based on the formula Calculate, where μ ι is the viscosity of the corresponding PVOH polymer.

[0068] Insoluble fiber forming material

[0069] The fibers of the present disclosure may include water-insoluble fiber-forming materials. Generally, water-insoluble fiber-forming materials include any material that does not dissolve in 300 seconds or less at a temperature of 80°C or less, as measured according to MSTM-205. Suitable water-insoluble fiber-forming materials include, but are not limited to, cotton, cellulose, polyester, polyethylene (e.g., high-density polyethylene and low-density polyethylene), polypropylene, polycarbonate, polybutylene terephthalate, polyethylene terephthalate, polyamide, thermoplastic polyurethane, wood pulp, fluff pulp, abaca, rayon, polylactic acid, nylon 6, cellulose, starch, jute, flax, ramie, sisal, bagasse, banana fiber, lacebark, silk, tendon, catgut, wool, algae fiber, mohair, angora, cashmere, collagen, actin, nylon, Dacron, rayon, bamboo fiber, modal fiber, diacetate fiber, triacetate fiber, and combinations thereof.

[0070] In an embodiment, the water-insoluble fiber-forming material comprises cotton, cellulose, jute, flax, ramie, sisal, bagasse, banana fiber, flower bark, silk, tendon, gut, wool, seaweed fiber, mohair, angora wool, cashmere, collagen, actin, nylon, polyester, rayon, bamboo fiber, modal fiber, diacetate fiber, triacetate fiber, polypropylene, polycarbonate, polybutylene terephthalate, polyethylene terephthalate, polyamide, thermoplastic polyurethane, rayon or a combination thereof. In an embodiment, the water-insoluble fiber-forming material comprises cotton, cellulose, wool, bamboo fiber, polypropylene, polycarbonate, rayon or a combination thereof. In an embodiment, the water-insoluble fiber-forming material comprises cellulose, wool, polypropylene, rayon or a combination thereof.

[0071] Auxiliary ingredients

[0072] The fibers of the present disclosure may include other additives and treatment agents, including but not limited to plasticizers, plasticizer extenders, surfactants, lubricants, mold release agents, fillers, extenders, crosslinking agents, anti-caking agents, antioxidants, anti-adhesive agents, defoaming agents, liquid absorbent materials (e.g., superabsorbent polymers), exfoliants, nanoparticles (e.g., layered silicate nanoclays (e.g., sodium montmorillonite)), bleaching agents (e.g., sodium metabisulfite, sodium bisulfite or others), repellents (e.g., bittering agents (e.g., denatonium salts (denatonium Salts, such as denatonium benzoate, denatonium sugars and denatonium chloride; sucrose octaacetate; quinine; flavonoids, such as quercetin and naringenin; and carotenoids, such as quassin and brucine) and pungents (such as capsaicin, piperine, allyl isothiocyanate, and resinferatoxin), as well as other functional ingredients, in amounts suitable for their intended purpose. Specific such adjuvants and treatment agents can be selected from those preparations suitable for water-soluble fibers, or those preparations suitable for water-soluble nonwoven fabrics.

[0073] In an embodiment, the fiber of the present disclosure comprises a plasticizer. A plasticizer is a liquid, solid, or semisolid that is added to a material (typically a resin or elastomer) to make the material softer, more flexible (by lowering the glass transition temperature of the polymer) and easier to handle. The polymer can be internally plasticized by chemically modifying the polymer or monomer (e.g., grafting the plasticizer onto the polymer backbone). Additionally or in an alternative, the polymer can be externally plasticized by adding a suitable plasticizer to the fiber-forming material. Additionally or in an alternative, the plasticizer can be added as a coating to the formed fiber or nonwoven fabric. Water is considered to be an extremely efficient plasticizer for PVOH and other polymers; including (but not limited to) water-soluble polymers, however, the volatility of water limits its utility because polymer fibers, nonwoven fabrics, and films need to have at least some resistance (robustness) to a variety of environmental conditions (including low and high relative humidity).

[0074] Plasticizers may include, but are not limited to, glycerol, diglycerol, sorbitol, ethylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, tetraethylene glycol, propylene glycol, polyethylene glycol up to 400 MW, neopentyl glycol, trimethylolpropane, polyether polyols, sorbitol, 2-methyl-1,3-propanediol Ethanolamine and mixtures thereof. The total amount of non-aqueous plasticizer provided in the fiber can be in the following ranges based on the total fiber weight: from about 1 wt.% to about 45 wt.%, or from about 5 wt.% to about 45 wt.%, or from about 10 wt.% to about 40 wt.%, or from about 20 wt.% to about 30 wt.%, from about 1 wt.% to about 4 wt.%, or from about 1.5 wt.% to about 3.5 wt.%, or from about 2.0 wt.% to about 3.0 wt.%, such as about 1 wt.%, about 2.5 wt.%, about 5 wt.%, about 10 wt.%, about 15 wt.%, about 20 wt.%, about 25 wt.%, about 30 wt.%, about 35 wt.% or about 40 wt.%.

[0075] In an embodiment, the fiber of the present disclosure includes a surfactant. The surfactant used in the fiber is well known in the art. Optionally, the surfactant is included to help the fiber disperse during processing (e.g., combing). Surfactants suitable for the fiber of the present disclosure include, but are not limited to, dialkyl sulfosuccinates, lactylated fatty acid esters of glycerol and propylene glycol, lactic acid esters of fatty acids, sodium alkyl sulfates, polysorbate 20, polysorbate 60, polysorbate 65, polysorbate 80, alkyl polyethylene glycol ethers, lecithin, acetylated fatty acid esters of glycerol and propylene glycol, sodium lauryl sulfate, acetylated esters of fatty acids, myristyl dimethylamine oxide, trimethyl tallow alkyl ammonium chloride, quaternary ammonium compounds, alkali metal salts of higher fatty acids containing about 8 to 24 carbon atoms, alkyl sulfates, alkyl polyethoxylated sulfates, alkyl benzene sulfonates, monoethanolamine, ethoxylated lauryl alcohol, propylene glycol, diethylene glycol, salts thereof, and combinations of any of the above.

[0076] Suitable surfactants may include nonionic, cationic, anionic and zwitterionic classes. Suitable surfactants include, but are not limited to, propylene glycol, diethylene glycol, monoethanolamine, polyoxyethylated polyoxypropylene glycol, alcohol ethoxylates, alkylphenol ethoxylates, tertiary acetylenic diols and alkanolamides (nonionic), polyoxyethylated amines, quaternary ammonium salts and quaternized polyoxyethylated amines (cationic), alkali metal salts of higher fatty acids containing about 8 to 24 carbon atoms, alkyl sulfates, alkyl polyethoxylated sulfates and alkyl benzene sulfonates (anionic), and amine oxides, N-alkyl betaines and sulfobetaines (zwitterionic). Other suitable surfactants include sodium dioctyl sulfosuccinate, lactylated fatty acid esters of glycerol and propylene glycol, lactic acid esters, sodium alkyl sulfates, polysorbate 20, polysorbate 60, polysorbate 65, polysorbate 80, lecithin, acetylated fatty acid esters of glycerol and propylene glycol, and acetylated esters of fatty acids, and combinations thereof. Surfactants may be included in or added to the fiber-forming material. In various embodiments, the amount of surfactant in the fiber is in the range of about 0.01wt.% to about 2.5wt.%, about 0.1wt.% to about 2.5wt.%, about 1.0wt.% to about 2.0wt.%, about 0.01wt% to 0.25wt% or about 0.10wt% to 0.20wt%.

[0077] In embodiments, the fibers of the present disclosure are substantially free of additives. As used herein and unless otherwise specified, "substantially free of additives" means that the fibers include less than about 0.01 wt%, less than about 0.005 wt.%, or less than about 0.001 wt.% additives based on the total weight of the fiber.

[0078] Active Agent

[0079] In an embodiment, the fiber may include one or more active agents as part of the fiber or may include one or more active agents on its surface. The active agent provides additional functionality to the fiber when present in an amount in the range of at least about 1 wt% or about 1 wt% to about 99 wt%. In an embodiment, the active agent is selected from the group consisting of: enzymes, oils, spices, colorants, odor absorbers, fragrances, pesticides, fertilizers, oxidants, exfoliants, liquid absorbing materials, activating factors, acid catalysts, metal catalysts, ion scavengers, detergents, disinfectants, surfactants, plasticizers, bleaches, bleaching components, fabric softeners, and combinations thereof. In an embodiment, the active agent is selected from the group consisting of: enzymes, oils, spices, colorants, odor absorbers, fragrances, pesticides, oxidants, exfoliants, liquid absorbing materials, detergents, disinfectants, surfactants, plasticizers, bleaches, bleaching components, fabric softeners, and combinations thereof. In an embodiment, the active agent is selected from the group consisting of: an enzyme, an oil, an odor absorber, a fragrance, an exfoliant, a liquid absorbing material, a detergent, a disinfectant, and combinations thereof.

[0080] In certain embodiments, the active agent may comprise an enzyme. Suitable enzymes include enzymes classified into any of the six general categories of the Enzyme Commission (EC), i.e., oxidoreductases of EC 1 (which catalyze oxidation / reduction reactions), transferases of EC 2 (which transfer functional groups, such as methyl or phosphate groups), hydrolases of EC 3 (which catalyze hydrolysis of multiple bonds), lyases of EC 4 (which cleave multiple bonds by means other than hydrolysis and oxidation), isomerases of EC 5 (which catalyze isomerization changes within a molecule), and ligases of EC 6 (which join two molecules via a covalent bond). Examples of such enzymes include dehydrogenases and oxidases of EC 1; transaminases and kinases of EC 2; lipases, cellulases, amylases, mannanases, and peptidases (also known as proteases or proteinases) of EC 3; decarboxylases of EC 4; isomerases and mutases of EC 5; and synthetases and synthetases of EC 6. Various classes of suitable enzymes are described, for example, in U.S. Pat. No. 9,394,092, the entire disclosure of which is incorporated herein by reference.

[0081] Enzymes for use in cleaning applications may include one or more of the following: proteases, amylases, lipases, dehydrogenases, transaminases, kinases, cellulases, mannanases, peptidases, decarboxylases, isomerases, mutases, synthetases, synthetases, and oxyanion-based reductases, including oxyanion-based reductases that catalyze the formation of bleaching agents.

[0082] It is contemplated that the enzyme used herein can be from any suitable source or combination of sources, such as bacteria, fungi, plants or animals. In one type of embodiment, a mixture of two or more enzymes will be from at least two different types of sources. For example, a mixture of a protease and a lipase can be from bacteria (protease) and fungi (lipase) sources.

[0083] Optionally, the enzymes used herein, including but not limited to any enzyme class or member described herein, are enzymes that function under alkaline pH conditions, such as when used in cleaning applications, such as a pH in the range of about 8 to about 11. Optionally, the enzymes used herein, including but not limited to any enzyme class or member described herein, are enzymes that function at a temperature in the range of about 5°C to about 45°C.

[0084] Another class of embodiments includes one or more odor absorbers as active agents. Odor absorbers suitable for use as active agents according to the present disclosure include, but are not limited to, zeolites, and complex zinc salts of ricinoleic acid. Deodorizing active agents may also include fixatives, which are well known in the art as most fragrances that are odor neutral, including, but not limited to, extracts of labdanum, styrax, and rosin acid derivatives.

[0085] Another class of embodiments includes one or more fragrances as active agents. As used herein, the term fragrance refers to any applicable material that is volatile enough to produce fragrance. Embodiments including fragrances as active agents may include fragrances that are pleasant to the senses, or alternatively, fragrances that repel people, animals and / or insects. Suitable fragrances include, but are not limited to, fruits, including, but not limited to, lemons, apples, cherries, grapes, pears, pineapples, oranges, strawberries, raspberries, musk and floral scents, including, but not limited to, lavender-like, rose-like, iris-like and carnation-like scents. Optionally, fragrances are also non-spice fragrances. Other fragrances include herbal scents, including, but not limited to, rosemary, thyme and sage; and woodland scents derived from pine, spruce and other forest odors. Fragrances can also be derived from a variety of oils, including, but not limited to, essential oils, or from plant materials, including, but not limited to, peppermint, green mint and the like. Suitable fragrance oils can be found in U.S. Pat. No. 6,458,754, which is incorporated herein by reference in its entirety. Suitable fragrance oils include, but are not limited to, 4-(2,2,6-trimethylcyclohex-1-enyl)-2-en-4-one, acetaldehyde styryl propyl acetal, 2,6,10-trimethyl-9-undecenal, 2-propenyl hexanoate, 1-octen-3-ol, trans-anethole, (z)-2-methyl-2-butenoic acid isobutyl ester, anisaldehyde diethyl acetal, 3-methyl-5-propyl-cyclohexene-1-one, 2,4- Dimethyl-3-cyclohexene-1-carbaldehyde, trans-4-decenal, decanal, 2-pentylcyclohexanone, ethyl anthranilate, eugenol, 3-(3-isopropylphenyl)butanol, methyl 2-octynoate, isoeugenol, cis-3-hexenyl methyl carbonate, linalool, methyl 2-nonenoate, 2-hydroxymethyl benzoate, nonanal, octanal, 2-nonenenitrile, 4-nonalactone, 9-decen-1-ol and 10-undecen-1-al. Suitable fragrances can also be found in U.S. Pat. Nos. 4,534,981, 5,112,688, 5,145,842, 6,844,302, and Perfumes Cosmetics and Soaps, 2nd edition, edited by W. A. ​​Pocket, 1959, all of which are incorporated herein by reference in their entirety. These fragrances include gum arabic, cinnamon, chypre, cyclamen, fern, gardenia, hawthorn, heliotrope, honeysuckle, hyacinth bean, jasmine, clove, lily, magnolia, mimosa, daffodil, fresh-cut hay, orange blossom, orchid, mignon, sweet pea, clover (clover), tuberose, vanilla, violet, wallflower, and the like.

[0086] The fragrance may include perfume. The perfume may include pure perfume, encapsulated perfume, or a mixture thereof. Preferably, the perfume includes pure perfume. A portion of the perfume may be encapsulated in the core shell encapsulation. In another type of embodiment, the perfume is not encapsulated in the core / shell encapsulation.

[0087] As used herein, the term "fragrance" encompasses both perfume raw materials (PRMs) and perfume blends. As used herein, the term "perfume raw material" refers to a compound having a molecular weight of at least about 100 g / mol and suitable for imparting an odor, aroma, essence or fragrance, either alone or in combination with other perfume raw materials. As used herein, the terms "perfume ingredient" and "perfume raw material" are interchangeable. As used herein, the term "blend" refers to a mixture of two or more PRMs.

[0088] Typical PRMs include alcohols, ketones, aldehydes, esters, ethers, nitrites and alkenes, such as terpenes, among others. Lists of common PRMs can be found in a variety of reference sources, for example, "Perfume and Flavor Chemicals" Volumes I and II; Steffen Arctander Allured Pub. (1994); and "Perfumes: Art, Science and Technology", Miller, PM and Lamparsky, D., Blackie Academic and Professional (1994). PRMs are characterized by their boiling point (BP) and their octanol / water partition coefficient (P) measured at atmospheric pressure (760 mm Hg). Based on these characteristics, PRMs can be classified as Quadrant I, Quadrant II, Quadrant III or Quadrant IV perfumes.

[0089] Suitable insect repellent fragrances include one or more of dichlorvos, pyrethrin, allethrin, naled and / or fenthion insecticides disclosed in U.S. Pat. No. 4,664,064, which is incorporated herein by reference in its entirety. Suitable insect repellents are citronellal (3,7-dimethyl-6-octanal), N,N-diethyl-3-methylbenzamide (DEET), vanillin, and essential oils extracted from turmeric (Curcuma longa), kaffir lime (Citrushystrix), lemongrass (Cymbopogon winterianus) and gray basil (Ocimum americanum). In addition, the insect repellent that is suitable may be a mixture of insect repellents.

[0090] In alternative embodiments, the active agent may optionally be an ion scavenger. Suitable ion scavengers include, but are not limited to, zeolites. Optionally, zeolites may be added as a water softener to an aqueous package containing a laundry detergent or dishwashing detergent encapsulated in the aqueous package.

[0091] Inorganic and organic bleaching agents are suitable cleaning active agents for use herein. Inorganic bleaching agents include perhydrate salts, including, but not limited to, perborates, percarbonates, perphosphates, persulfates, and persilicates. Inorganic perhydrate salts are typically alkali metal salts. Alkali metal percarbonates, especially sodium percarbonate, are perhydrates suitable for use herein. Organic bleaching agents may include organic peroxy acids, including diacyl and tetraacyl peroxy acids, especially, but not limited to, diperoxydodecanedioic acid, diperoxytetradecandioic acid, and diperoxyhexadecanedioic acid. Dibenzoyl peroxide is a suitable organic peroxy acid according to the present disclosure. Other organic bleaching agents include peroxy acids, with specific examples being alkyl peroxy acids and aryl peroxy acids.

[0092] In one class of embodiments, the active agent may comprise a bleach activator, including an organic peracid precursor that enhances bleaching during cleaning at temperatures of 60°C and below. Suitable bleach activators for use herein include compounds that yield aliphatic peroxycarboxylic acids having 1 to 10 carbon atoms, or 2 to 4 carbon atoms, and / or optionally substituted perbenzoic acids under perhydrolysis conditions. Suitable materials carry O-acyl and / or N-acyl groups having the specified number of carbon atoms and / or optionally substituted benzoyl groups. Suitable materials include, but are not limited to, polyacylated alkylenediamines, specifically tetraacetylethylenediamine (TAED); acylated triazine derivatives, specifically 1,5-diacetyl-2,4-dioxohexahydro-1,3,5-triazine (DADHT); acylated glycoluril, specifically tetraacetyl glycoluril (TAGU); N-acylimide, specifically n-nonanoyl succinimide (NOSI); acylated phenol sulfonate, specifically n-nonanoyl or isononanoyloxybenzenesulfonate (n- or iso-NOBS); carboxylic anhydride, specifically phthalic anhydride; acylated polyols, specifically triacetin, ethylene glycol diacetate and 2,5-diacetoxy-2,5-dihydrofuran, and triethylacetyl citrate (TEAC).

[0093] In embodiments comprising a fabric softener as an active agent, various thorough washing fabric softeners, particularly the untouchable bentonite clay of U.S. Pat. No. 4,062,647 (incorporated herein by reference in its entirety), and other softener clays known in the art, may optionally be used to provide fabric softener benefits while fabrics are cleaned. Clay softeners may be used in combination with amine and cationic softeners as disclosed in, for example, U.S. Pat. Nos. 4,375,416 and 4,291,071 (incorporated herein by reference in their entirety).

[0094] In an embodiment, the active agent may include a disinfectant. Suitable disinfectants for use herein may include, but are not limited to, hydrogen peroxide, inorganic peroxides and their precursors, sodium metabisulfite, quaternary ammonium cation-based compounds, chlorine, activated carbon, and hypochlorites.

[0095] In an embodiment, the active agent may include a surfactant. Suitable surfactants for use herein may include, but are not limited to, propylene glycol, diethylene glycol, monoethanolamine, polyoxyethylene polyoxypropylene glycol, alcohol ethoxylates, alkylphenol ethoxylates, tertiary acetylenic diols and alkanolamides (nonionic), polyoxyethylene amines, quaternary ammonium salts and quaternary polyoxyethylene amines (cationic), alkali metal salts of higher fatty acids containing about 8 to 24 carbon atoms, alkyl sulfates, alkyl polyethoxylated sulfates and alkyl benzene sulfonates (anionic), amine oxides, N-alkyl betaines and sulfobetaines (zwitterionic), sodium dioctyl sulfosuccinate, lactylated fatty acid esters of glycerol and propylene glycol, lactic acid esters, sodium alkyl sulfates, polysorbate 20, polysorbate 60, polysorbate 65, polysorbate 80, lecithin, acetylated fatty acid esters of glycerol and propylene glycol, and acetylated esters of fatty acids, and combinations thereof.

[0096] The active agent can be solid or liquid.The solid active agent can have, for example, an average particle size (eg, Dv50) of at least about 0.01 μm, or a size in the range of about 0.01 μm to about 2 mm.

[0097] In embodiments, the fibers of the nonwoven fabrics, composite articles, flushable tissues, liquid-containing articles, and absorbent articles of the present disclosure include water-soluble fibers, water-insoluble fibers, or a combination thereof, wherein the fibers may have the same or different diameters, lengths, tenacity, shapes, rigidity, elasticity, solubility, melting points, glass transition temperatures, and / or fiber-forming materials.

[0098] In embodiments where the fiber comprises a water-soluble fiber, the water-soluble fiber may comprise any of the water-soluble polymer fiber-forming materials disclosed herein. Generally, the water-soluble fiber may comprise a single water-soluble polymer fiber-forming material, or a blend of water-soluble fiber-forming materials. In embodiments, the water-soluble fiber consists of a single water-soluble polymer fiber-forming material. In embodiments, the water-soluble fiber comprises a blend of water-soluble polymers.

[0099] In an embodiment, a plurality of water-soluble fibers include polyvinyl alcohol (PVOH) fiber-forming materials. In a modification of the above embodiment, the water-soluble fiber-forming material includes a PVOH homopolymer. In another modification of the above embodiment, the water-soluble fiber-forming material includes a PVOH copolymer. In an embodiment, the water-soluble fiber includes a blend of polyvinyl alcohol fiber-forming materials. In a modification of the above embodiment, the water-soluble fiber includes one or more PVOH homopolymer fiber-forming materials. In another modification of the above embodiment, the water-soluble fiber includes one or more PVOH copolymer fiber-forming materials. In yet another modification of the above embodiment, the water-soluble polymer includes one or more PVOH homopolymer fiber-forming materials and one or more PVOH copolymer fiber-forming materials.

[0100] In embodiments where the water-soluble fiber comprises a blend of a polyvinyl alcohol homopolymer and a polyethylene copolymer, the polyvinyl alcohol homopolymer can account for about 15 wt.% to about 70 wt.%, such as at least about 15 wt.%, at least about 20 wt.%, at least about 25 wt.%, at least about 30 wt.%, at least about 40 wt.%, at least about 50 wt.%, or at least about 60 wt.%, and at most about 70 wt.%, at most about 60 wt.%, at most about 50 wt.%, at most about 40 wt.%, or at most about 30 wt.%, based on the total weight of the water-soluble polymer blend, and can be a single homopolymer, or a blend of one or more homopolymers (e.g., having differences in viscosity and / or degree of hydrolysis). Based on the total weight of the water-soluble polymer blend, the water-soluble polyvinyl alcohol copolymer can account for about 30wt.% to about 85wt.% of the total weight of the water-soluble polymer blend, such as at least about 30wt.%, at least about 40wt.%, at least about 50wt.%, at least about 60wt.%, at least about 70wt.%, at least about 75wt.% or at least about 80wt.% and at most about 85wt.%, at most about 80wt.%, at most about 70wt.%, at most about 60wt.%, at most about 50wt.% or at most about 40wt.%, and can be a single copolymer, or a blend of one or more copolymers. The blend can be composed of a polyvinyl alcohol homopolymer and a polyvinyl alcohol copolymer. The blend can be composed of a polyvinyl alcohol homopolymer and a plurality of polyvinyl alcohol copolymers. The blend can be composed of more than one polyvinyl alcohol homopolymer and more than one polyvinyl alcohol copolymer.

[0101] Biodegradability

[0102] Polyvinyl alcohol polymers are generally biodegradable due to their decomposition in the presence of water and enzymes, under aerobic, anaerobic, soil and composting conditions (in the presence of water). Generally, the biodegradation activity of polyvinyl alcohol polymers increases as the degree of hydrolysis of the polyvinyl alcohol polymer increases up to about 80%. Without wishing to be bound by theory, it is believed that increasing the degree of hydrolysis above 80% has little effect on biodegradability.

[0103] Without wishing to be bound by theory, it is believed that while the degree of polymerization of the polyvinyl alcohol polymer has little to no effect on the biodegradability of fibers or nonwovens prepared from the polymer, the polymerization temperature can affect the biodegradability of the film or nonwoven because the polymerization temperature can affect the crystallinity and aggregation state of the polymer. Specifically, as the crystallinity decreases, the polymer chain hydroxyls become less aligned in the polymer structure and the polymer chains become less ordered, which allows the chains to accumulate as amorphous aggregates, thereby reducing the availability of the ordered polymer structure, and thus the biodegradation activity is expected to decrease due to soil and / or compost biodegradation mechanisms, in which the polymer is not soluble.

[0104] In addition, the stereoregularity of the hydroxyl groups of the polyvinyl alcohol polymer has a greater impact on the level of biodegradability activity, and the more isotactic the hydroxyl groups of the polymer sequence, the higher the degradation activity becomes. Without wishing to be bound by theory, it is believed that since the stereoregularity of the hydroxyl groups of the polyvinyl alcohol polymer has a greater impact on the level of biodegradability activity, substitution of functional groups other than hydroxyl groups (e.g., anionic AMPS functional groups, carboxylate groups, or lactone groups) is expected to reduce the level of biodegradability activity (relative to a polyvinyl alcohol homopolymer with the same degree of hydrolysis), unless the functional group itself is also biodegradable, in which case the substitution can increase the biodegradability of the polymer. In addition, it is believed that although the level of biodegradability activity of the substituted polyvinyl alcohol will be less than that of the corresponding homopolymer, the substituted polyvinyl alcohol will still exhibit biodegradability. In addition, without wishing to be bound by theory, for soil and / or compost biodegradation, it is believed that the level of biodegradability activity of nonwoven fabrics prepared from polyvinyl alcohol fibers will be higher than that of water-soluble films prepared from similar polyvinyl alcohol polymers because the nonwoven fabric provides an increased polymer surface area relative to the film.

[0105] Biodegradation activity assays are known in the art. Suitable standards include OECD 301B (ready biodegradability), OECD 302B (inherent biodegradability), OECD 311 (anaerobic), and ASTM D5988 (soil).

[0106] Fiber properties

[0107] The plurality of fibers may be prepared by any process known in the art, such as wet-chilled gel spinning, thermoplastic fiber spinning, meltblowing, spunbonding, electrospinning, roto-spinning, continuous filament production operations, tow fiber production operations, and combinations thereof.

[0108] In an embodiment, the fiber comprises a water-soluble fiber prepared by wet cooling gel spinning, meltblowing, spunbonding, or a combination thereof. In an embodiment, the fiber comprises a water-soluble fiber, the water-soluble fiber is prepared by wet cooling gel spinning and is combed into a nonwoven fabric. In an embodiment, the fiber comprises a water-soluble fiber and the nonwoven fabric prepared therefrom is formed by a continuous meltblowing process. In an embodiment, the fiber comprises a water-soluble fiber and the nonwoven fabric prepared therefrom is formed by a continuous spunbonding process. In the art, the standard refers to the fiber and the nonwoven fabric made by the process for preparing a nonwoven fabric. Therefore, any reference to, for example, "meltblown fibers" or "combed nonwoven fabrics" herein should not be understood as limiting the product to a specific meltblowing or combing method, but only to identify a specific fiber or fabric. Therefore, the term processing can be used to distinguish fibers and / or nonwoven fabrics, rather than limiting the fibers and / or nonwoven fabrics to the preparation of any specific process.

[0109] The fiber of the present disclosure may be a bicomponent fiber. As used herein and unless otherwise specified, "bicomponent fiber" does not refer to a fiber comprising a blend of fiber-forming materials, but rather refers to a fiber comprising two or more different regions of a fiber-forming material, wherein the composition of the fiber-forming material varies from region to region. Examples of bicomponent fibers include, but are not limited to, core / sheath bicomponent fibers, island-in-the-sea bicomponent fibers, and side-by-side bicomponent fibers. A core / sheath bicomponent fiber generally comprises a core of a fiber-forming material of a first composition (e.g., a single fiber-forming material, or a first blend of fiber-forming materials), and a sheath of a fiber-forming material of a second composition (e.g., a single fiber-forming material different from the core material, or a second blend of fiber-forming materials different from the first blend of fiber-forming materials of the core). An island-in-the-sea bicomponent fiber generally comprises a first continuous "ocean" region of a fiber-forming material of a first composition and discrete "island" regions of a fiber-forming material having a second composition different from the first composition dispersed therein. Side-by-side bicomponent fibers generally include a first region extending the length of the fiber and comprising a fiber-forming material of a first composition, and at least a second region adjacent thereto extending the length of the fiber and comprising a fiber-forming material of a second composition different from the first composition. Such bicomponent fibers are well known in the art.

[0110] The fiber of the present disclosure can be hydrophobic and / or hydrophilic fiber.As used herein and unless otherwise specified, "hydrophobic fiber" refers to any fiber with a hydrophobic surface.Fiber can have a hydrophobic surface, and now fiber includes, for example, hydrophobic fiber forming material, fiber is a core / sheath type bicomponent fiber, its sheath includes hydrophobic fiber forming material, and / or fiber has been surface-treated to include a hydrophobic surfactant on its surface.Similarly, as used herein and unless otherwise specified, "hydrophilic fiber" refers to any fiber with a hydrophilic surface.Fiber can have a hydrophilic surface, and now fiber includes, for example, hydrophilic fiber forming material, fiber is a core / sheath type bicomponent fiber, its sheath includes hydrophilic fiber forming material, and / or fiber has been surface-treated to include a hydrophilic material on its surface.Not wishing to be limited by theory, it is believed that the hydrophilic fiber of nonwoven fabric can promote the capillary action / wicking of the nonwoven fabric surface to liquid, relative to the same nonwoven fabric not including hydrophilic fibers, so that liquid collection is improved.

[0111] The fiber of the present disclosure may include one or more fiber-forming materials disclosed herein. When the fiber includes a PVOH polymer fiber-forming material, the fiber hydrolysis degree is the same as the PVOH polymer hydrolysis degree. When the fiber includes two or more PVOH polymer fiber-forming materials, the fiber hydrolysis degree is the arithmetic weighted average of the hydrolysis degrees of the individual PVOH polymers. Without wishing to be limited by theory, it is believed that when the fiber hydrolysis degree increases, the fiber hydrophilicity increases and as a result, the wicking rate of the fiber increases. Therefore, nonwoven fabrics including fibers with a relatively high average hydrolysis degree may be particularly suitable for applications in which wicking rate is a major factor, such as wearable items that wish to quickly wick liquid and detach the liquid from the skin of consumers. In embodiments in which wicking rate is a major factor, the fiber of the present disclosure may have a hydrolysis degree (average) of about 95% to about 99.9%.

[0112] The fiber shape is not particularly limited and may have a cross-sectional shape including, but not limited to, circular, oval (also referred to as ribbon), triangular (also referred to as △), trilobal, and / or other multilobal shapes. Figure 1 ). It should be understood that the fiber shape is not necessarily a perfect geometric shape, for example, a fiber having a circular cross-sectional shape does not necessarily have a perfect circle in the cross-sectional area, and a fiber having a triangular cross-sectional shape generally has rounded corners. Without wishing to be limited by theory, it is believed that hydrophilic fibers (e.g., trilobal fibers) in a nonwoven fabric having a shape that provides capillary or channel-type directional channels to liquids can promote capillary action / wicking of liquids by the nonwoven fabric surface, relative to the same nonwoven fabric whose fiber shape does not include capillary or channel-type directional channels, resulting in improved liquid acquisition.

[0113] It is understood that fiber diameter refers to the cross-sectional diameter of the fiber along the longest cross-sectional axis. When a fiber is described as having (or not having) a particular diameter, unless otherwise specified, it is intended that the specified diameter is the average diameter of the particular fiber type being referred to, i.e., a plurality of fibers prepared from a polyvinyl alcohol fiber-forming material has the arithmetic mean fiber diameter of the plurality of fibers. For shapes that are not typically considered to have a "diameter" (e.g., triangular or multi-lobed shapes), the diameter refers to the diameter of a circle surrounding the fiber shape ( Figure 1 ).

[0114] The fibers of the present disclosure typically have a diameter in the range of about 10 microns to 300 microns, such as at least 10 microns, at least 15 microns, at least 20 microns, at least 25 microns, at least 50 microns, at least 100 microns, or at least 125 microns, and at most about 300 microns, at most about 275 microns, at most about 250 microns, at most about 225 microns, at most about 200 microns, at most about 100 microns, at most about 50 microns, at most about 45 microns, at most about 40 microns, or at most about 35 microns, such as in the range of about 10 microns to about 300 microns, about 50 microns to about 300 microns, about 100 microns to about 300 microns, about 100 microns to about 50 microns, about 10 microns to about 45 microns, or about 10 microns to about 40 microns. In an embodiment, the water-soluble fibers used to prepare the water-dispersible nonwoven fabrics of the present disclosure may have a diameter of greater than 100 microns to about 300 microns. In an embodiment, the fiber comprises cellulose having a diameter in the range of about 10 microns to about 50 microns, about 10 microns to about 30 microns, about 10 microns to about 25 microns, about 10 microns to about 20 microns, or about 10 microns to about 15 microns. In an embodiment, the fiber comprises a water-soluble fiber-forming material and has a diameter of about 50 microns to about 300 microns, about 100 microns to about 300 microns, about 150 microns to about 300 microns, or about 200 microns to about 300 microns. In an embodiment, the diameter of a plurality of water-soluble fibers used to prepare the water-dispersible nonwoven fabric of the present disclosure has a substantially uniform diameter. As used herein, if the diameter difference between the fibers is less than 10% (e.g., 8% or less, 5% or less, 2% or less, or 1% or less), the fiber diameter is "substantially uniform". Fibers having substantially uniform diameters can be prepared by a wet cooling gel spinning process or thermoplastic fiber spinning, as described herein. In addition, when a fiber blend is used, the average fiber diameter can be determined using the weighted average of the individual fibers.

[0115] The fibers of the present disclosure for preparing nonwoven fabrics and nonwoven composite articles of the present disclosure can generally have any length. In an embodiment, the fiber length can be in the range of about 20 mm to about 100 mm, about 20 to about 90, about 30 mm to about 80 mm, about 10 mm to about 60 mm, or about 30 mm to about 60 mm, such as at least about 30 mm, at least about 35 mm, at least about 40 mm, at least about 45 mm, or at least about 50 mm and at most about 100 mm, at most about 95 mm, at most about 90 mm, at most about 80 mm, at most about 70 mm, or at most about 60 mm. In an embodiment, the length of the water-soluble fiber can be less than about 30mm or in the range of about 0.25mm to less than about 30mm, such as at least about 0.25mm, at least about 0.5mm, at least about 0.75mm, at least about 1mm, at least about 2.5mm, at least about 5mm, at least about 7.5mm, or at least about 10mm and at most about 29mm, at most about 28mm, at most about 27mm, at most about 26mm, at most about 25mm, at most about 20mm or at most about 15mm. Fiber can be made into any length by cutting and / or curling the extruded polymer mixture. In an embodiment, fiber can be continuous filaments, such as continuous filaments prepared by the following process: such as spunbond, meltblown, electrospinning and spin spinning, wherein continuous filaments are prepared in fabric form and directly provided. In addition, when using fiber blends, fiber average length can be measured using the weighted average of individual fibers.

[0116] The fibers of the present disclosure may generally have any length to diameter ratio. In embodiments, the length to diameter ratio of the fibers may be greater than about 2, greater than about 3, greater than about 4, greater than about 6, greater than about 10, greater than about 50, greater than about 60, greater than about 100, greater than about 200, greater than about 300, greater than about 400, or greater than about 1000.

[0117] The fibers used to prepare the nonwoven fabrics of the present invention can generally have any tenacity. Fiber tenacity is related to fiber roughness. In general, when fiber tenacity decreases, fiber roughness increases. The fibers used to prepare the nonwoven fabrics of the present invention can have a tenacity in the following range: about 1 to about 100 cN / dtex, or about 1 to about 75 cN / dtex, or about 1 to about 50 cN / dtex, or about 1 to about 45 cN / dtex, or about 1 to about 40 cN / dtex, or about 1 to about 35 cN / dtex, or about 1 to about 30 cN / dtex, or about 1 to about 25 cN / dtex, or about 1 to about 20 cN / dtex, or about 1 to about 15 cN / dtex, or about 1 to about 10 cN / dtex, or about 1 to about 5 cN / dtex, or about 3 to about 8 cN / dtex, or about 4 In an embodiment, the fiber may have a tenacity of about 3 cN / dtex to about 10 cN / dtex. In an embodiment, the fiber may have a tenacity of about 7 cN / dtex to about 10 cN / dtex. In an embodiment, the fiber may have a tenacity of about 7 cN / dtex to about 10 cN / dtex. In an embodiment, the fiber may have a tenacity of about 4 cN / dtex to about 8 cN / dtex. In an embodiment, the fiber may have a tenacity of about 6 cN / dtex to about 8 cN / dtex.

[0118] In embodiments where the fiber is prepared using a wet cooling gel spinning process, the resulting fiber can generally have any tenacity as described herein. In improvements to the above embodiments, the fiber can have a tenacity in the following ranges: from about 3 to about 15, from about 3 to about 13, from about 3 cN / dtex to about 10 cN / dtex, from about 5 cN / dtex to about 10 cN / dtex, or from about 6 cN / dtex to about 10 cN / dtex, from about 7 cN / dtex to about 10 cN / dtex, from about 4 cN / dtex to about 8 cN / dtex, or from about 6 cN / dtex to about 8 cN / dtex.

[0119] The fiber used to prepare the nonwoven fabric of the present disclosure can have any fineness usually.The fineness of fiber is related to the mass length ratio of fiber.The main physical unit of fiber fineness is 1tex, which is equal to 1000m fiber weight 1g.Typically, the unit dtex is used, which represents 10,000m fiber 1g.In order to provide a nonwoven fabric with suitable hardness / hand feel, torsional rigidity, light reflection and interaction, absorption of dye and / or other active agents / additives, fiber spinning simplicity in manufacturing process and finished product uniformity, the fineness of fiber can be selected.In general, when the fineness of fiber increases, the nonwoven fabric obtained therefrom exhibits higher uniformity, improved tensile strength, ductility and gloss.In addition, it is not desired to be limited by theory, based on density, it is believed that compared with larger fibers, thinner fibers cause slower dissolution time.In addition, it is not desired to be limited by theory, when using fiber blends, the average fineness of fiber can be measured using the weighted average of individual fiber components. The fibers can be characterized as very fine (dtex≤1.22), fine (1.22≤dtex≤1.54), medium (1.54≤dtex≤1.93), slightly coarse (1.93≤dtex≤2.32), and coarse (dtex≥2.32). The nonwoven fabric of the present disclosure may include fibers that are very fine, fine, medium, slightly coarse, or a combination thereof. In an embodiment, the fibers have a fineness in the range of about 1 dtex to about 10 dtex, about 1 dtex to about 7 dtex, about 1 dtex to about 5 dtex, about 1 dtex to about 3 dtex, or about 1.7 dtex to about 2.2 dtex. In an embodiment, the fibers have a fineness of about 1.7 dtex. In an embodiment, the fibers have a fineness of about 2.2 dtex.

[0120] The plurality of water-soluble fibers may be prepared by any process known in the art, such as thermoplastic fiber spinning, wet cooled gel spinning, melt blowing, spunbonding, electrospinning, roto-spinning, continuous filament production operations, tow fiber production operations, and combinations thereof.

[0121] Wet cooling gel spinning

[0122] In an embodiment, the plurality of fibers include fibers prepared according to a wet cooling gel spinning process, the wet cooling gel spinning process comprising the steps of

[0123] (a) dissolving a fiber-forming polymer (or polymers) in a solution to form a polymer mixture, the polymer mixture optionally including an adjuvant;

[0124] (b) extruding the polymer mixture through a spinneret nozzle into a coagulation bath to form an extruded polymer mixture;

[0125] (c) passing the extruded polymer mixture through a solvent exchange bath;

[0126] (d) optionally wet drawing the extruded polymer mixture; and

[0127] (e) subjecting the extruded polymer mixture to a finishing process to provide the fibers.

[0128] The solvent in which the fiber-forming polymer is dissolved may suitably be any solvent in which the polymer is soluble. In an embodiment, the solvent in which the polymer is dissolved comprises a polar aprotic solvent. In an embodiment, the solvent in which the polymer is dissolved comprises dimethyl sulfoxide (DMSO).

[0129] In general, the coagulation bath includes a cooling solvent for gelling the extruded polymer mixture. The coagulation bath can generally be at any temperature that promotes coagulation of the extruded polymer mixture. The coagulation bath can include a mixture of a solvent that can dissolve the polymer and a solvent that cannot dissolve the polymer. The solvent that cannot dissolve the polymer is generally the main solvent, wherein the solvent that cannot dissolve the polymer accounts for more than 50% of the mixture.

[0130] The extruded polymer mixture may pass through one or more solvent exchange baths after passing through the coagulation bath. The solvent exchange baths are provided to exchange the solvent that can dissolve the polymer for a solvent that cannot dissolve the polymer to further coagulate the extruded polymer mixture, and to exchange the solvent that can dissolve the polymer for a solvent that evaporates more easily, thereby shortening the drying time. The solvent exchange baths may include: a series of solvent exchange baths with a solvent gradient in which the solvent that can dissolve the polymer is exchanged for a solvent that cannot dissolve the polymer; a series of solvent exchange baths with only a solvent that cannot dissolve the polymer; or a single solvent exchange bath with only a solvent that cannot dissolve the polymer.

[0131] Finished fibers are sometimes referred to as staple fibers, ultrashort fibers, or pulp. In an embodiment, the finishing process includes drying the extruded polymer mixture. In an embodiment, the finishing process includes cutting or curling the extruded polymer mixture to form individual fibers. Wet drawing the extruded polymer mixture provides a substantially uniform diameter for the extruded polymer mixture, and thereby provides a substantially uniform diameter for the fibers cut therefrom. As is well known in the art, drawing is different from extrusion. Specifically, extrusion refers to the operation of forcing a resin mixture through a spinning head to make fibers, while drawing refers to mechanically pulling the fibers in the processing direction to promote polymer chain orientation and crystallinity that is conducive to increasing fiber strength and toughness.

[0132] In embodiments where the fibers are prepared using a wet cooling gel spinning process, the fiber-forming polymer can generally be any fiber-forming polymer or a blend thereof, such as two or more different polymers, as generally described herein. In a refinement of the above embodiments, the polymer can have any degree of polymerization (DP), such as in the range of 10 to 10,000,000, such as at least 10, at least 20, at least 50, at least 100, at least 200, at least 300, at least 400, at least 500, at least 750, or at least 1000, and at most 10,000,000, at most 5,000,000, at most 2,500,000, at most 1,000,000, at most 900,000, at most 750,000, at most 500,000, at most 250,000, at most 100,000, at most 90,000, at most 75 ... In some embodiments, the DP is at least 1,000, about 50 to about 10,000, about 50 to about 900, about 100 to about 800, about 150 to about 700, about 200 to about 600, or about 250 to about 500. In some embodiments, the DP is at least 1,000, about 50 to about 10,000, about 50 to about 900, about 100 to about 800, about 150 to about 700, about 200 to about 600, or about 250 to about 500. In some embodiments, the DP is at least 1,000, about 50 to about 10,000, about 50 to about 5,000, about 50 to about 2,500, about 50 to about 12,000, about 50 to about 10,000, about 50 to about 5,000, about 50 to about 2,500, about 50 to about 1000, about 50 to about 900, about 100 to about 800, about 150 to about 700, about 200 to about 600, or about 250 to about 500. In embodiments, the fiber-forming polymer comprises a polyvinyl alcohol polymer having a DP in the range of 1000 to about 50,000, 1000 to about 25,000, 1000 to about 12,000, 1000 to about 5,000, 1000 to about 2,500, about 50 to about 12,000, about 50 to about 10,000, about 50 to about 5,000, about 50 to about 2,500, about 50 to about 1000, about 50 to about 900, about 100 to about 800, about 150 to about 700, about 200 to about 600, or about 250 to about 500. In embodiments, the fiber-forming polymer comprises a polyvinyl alcohol having a DP in the range of 1000 to about 50,000, 1000 to about 25,000, 1000 to about 12,000, 1000 to about 5,000, or 1000 to about 2,500.

[0133] Thermoplastic Fiber Spinning

[0134] Thermoplastic fiber spinning is well known in the art. Briefly, thermoplastic fiber spinning includes the following steps:

[0135] (a) preparing a polymer mixture comprising a fiber-forming polymer, which optionally includes an adjuvant;

[0136] (b) extruding the polymer mixture through a spinneret nozzle to form an extruded polymer mixture;

[0137] (c) optionally drawing the extruded polymer mixture; and

[0138] (d) subjecting the extruded polymer mixture to a finishing process to provide the fibers.

[0139] The finished staple fibers of the thermoplastic fiber spinning process can be processed by drying, cutting and / or crimping to form individual fibers. Drawing the extruded polymer mixture is to mechanically pull the fibers in the process direction, promoting polymer chain orientation and crystallinity to increase fiber strength and toughness. Preparing the polymer mixture for thermoplastic fiber spinning can typically include (a) preparing a solution of fiber-forming material and a volatile solvent so that after the solution is extruded through a spinning head, the solution is contacted with a hot air stream and the solvent evaporates easily to leave solid fibers, or (b) melting the polymer so that after the hot polymer is extruded through the spinning head, the polymer is quenched and solidified by cold air. The thermoplastic fiber spinning process differs from the wet cooling gel spinning process at least in that (a) in the thermoplastic fiber spinning process, the extruded fibers are solidified by solvent evaporation or by cold air quenching the hot solid fibers, rather than by using a coagulation bath; and (b) in the wet cooling gel spinning process, drawing is optionally performed while the fibers are in a gel state rather than a solid state.

[0140] The fiber-forming material for preparing fibers using a thermoplastic fiber spinning process can generally be any fiber-forming polymer or a blend thereof, such as two or more different polymers, provided that the polymer or its blend has a suitable solubility in a volatile solvent and / or has a melting point that is lower than and different from its degradation temperature. In addition, when a fiber-forming polymer blend is used to make fibers, the fiber-forming material must have a similar solubility in a volatile solvent and / or have a similar thermal profile. In contrast, the fiber-forming material for preparing fibers using a wet cooling gel spinning process is not limited, and the fibers can be prepared from a blend of any two or more polymers dissolved in the same solvent system, and the solvent system is not necessarily a single solvent or even a volatile solvent.

[0141] The fiber-forming polymer used to prepare the thermoplastic fiber spinning may have, for example, a degree of polymerization (DP) ranging from 10 to 10,000, such as at least 10, at least 20, at least 50, at least 100, at least 200, at least 300, at least 400, at least 500, at least 750, or at least 1000 and up to 10,000, up to 5,000, up to 2,500, up to 1,000, up to 900, up to 750, up to 500, or up to 250. In an embodiment, the DP is less than 1,000.

[0142] Melt Spinning

[0143] Melt spinning is well known in the art and is understood to refer to the spunbond process and the meltblown process. Melt spinning is a continuous process that produces nonwoven fabrics directly while the fibers are being formed. Therefore, the fibers formed by melt spinning are not finished and cut into any constant length (e.g., staple fibers are not produced by these processes). In addition, melt spinning does not include a drawing step, so the only control over the diameter of the resulting melt-spun fibers is the size of the holes through which the fiber-forming material is extruded, and the polymer chains are typically not oriented in any particular orientation.

[0144] In simple terms, melt spinning involves the following steps:

[0145] (a) preparing a polymer mixture comprising a fiber-forming polymer, which optionally includes an adjuvant;

[0146] (b) extruding the polymer mixture into a die assembly to form an extruded polymer mixture;

[0147] (c) quenching the extruded polymer mixture;

[0148] (d) depositing the quenched, extruded polymer mixture onto a conveyor belt to form a nonwoven fabric; and

[0149] (e) bonding the nonwoven fabric.

[0150] In the spunbond process, the extruded polymer mixture is drawn into a die assembly as a molten polymer and is quenched by cold air after passing through the die assembly. In the meltblowing process, the extruded polymer mixture is drawn into a die assembly sprayed with hot air and is quenched upon exiting the die assembly and contacting ambient temperature air. In both processes, the fibers are continuously dropped onto a conveyor belt or drum, which is usually facilitated by drawing a vacuum underneath the conveyor belt or drum.

[0151] The diameter of the spunbond fibers is typically in the range of about 0.1 to about 50 microns, for example, at least about 0.1 microns, at least about 1 micron, at least about 2 microns, at least about 5 microns, at least about 10 microns, at least about 15 microns, or at least about 20 microns and up to about 50 microns, up to about 40 microns, up to about 30 microns, up to about 25 microns, up to about 20 microns, up to about 15 microns, up to about 10 microns, from about 0.1 micron to about 50 microns, from about 0.1 micron to about 40 microns, from about 0.1 micron to about 30 microns. The invention relates to a spunbond fiber having an average fiber diameter of about 1 to 10 microns, about 0.1 microns to about 25 microns, about 0.1 microns to about 20 microns, about 0.1 microns to about 15 microns, about 0.1 microns to about 10 microns, about 0.1 microns to about 9 microns, about 0.1 microns to about 8 microns, about 0.1 microns to about 7 microns, about 0.1 microns to about 6 microns, about 0.1 microns to about 6 microns, about 5 microns to about 35 microns, about 5 microns to about 30 microns, about 7.5 microns to about 25 microns, about 10 microns to about 25 microns, or about 15 microns to about 25 microns. It is well known in the art that the meltblowing process can provide microfibers with an average diameter in the range of about 1 to 10 microns, however, there is a very high difference in diameter between fibers obtained by the meltblowing process, such as a 100-300% difference. In addition, it is well known in the art that spunbond fibers can have a larger average fiber diameter, such as typically about 15 to about 25 microns, but the uniformity between fibers is improved, such as about 10% difference.

[0152] The fiber-forming materials used in hot extrusion processes (e.g., melt spinning, thermoplastic fiber spinning) are subject to greater restrictions than wet cooling gel spinning processes. In general, the degree of polymerization of hot extrusion processes is limited to a range of about 200 to about 500. When the degree of polymerization is reduced to less than 200, the viscosity of the fiber-forming material is too low, and the individual fibers prepared by suctioning the material through the die assembly cannot maintain sufficient separation after leaving the die assembly. Similarly, when the degree of polymerization is increased to more than 500, the viscosity is too high to efficiently suction the material through the sufficiently small holes in the die assembly, thereby failing to run the process at high speeds, thereby losing process efficiency and fiber and / or nonwoven fabric uniformity. In addition, since homopolymers generally do not have the necessary thermal stability, processes that require heating fiber-forming materials are not suitable for polyvinyl alcohol homopolymers. In addition, it is known that melt-processable polymers are those polymers with a viscosity of 5 cP or less. Therefore, the wet cooling gel spinning process can advantageously provide fibers using polymers (including polyvinyl alcohol homopolymers and copolymers) with a viscosity greater than 5 cP that could not be processed into fibers.

[0153] The wet cooling gel spinning process advantageously provides one or more benefits, such as providing fibers including water-soluble polymer blends, providing control over fiber diameter, providing relatively large diameter fibers, providing control over fiber length, providing control over fiber tenacity, providing high-strength fibers, providing fibers having a large degree of polymerization, and / or providing fibers that can be used to provide self-supporting nonwoven fabrics. Continuous processes (e.g., spunbond, meltblown, electrospinning, and spin spinning) generally do not consider blending water-soluble polymers (e.g., due to the difficulty in matching the melt index of different polymers), forming large diameter (e.g., greater than 50 microns) fibers, controlling fiber length, providing high-strength fibers, and using polymers having a high degree of polymerization. In addition, the wet cooling gel spinning process has the advantage of not being limited to only melt-processable polymers and therefore can obtain fibers made of fiber-forming materials having extremely high molecular weights, high melting points, low melt flow indexes, or combinations thereof, providing fibers with stronger physical properties and different chemical functional groups than fibers prepared by hot extrusion processes.

[0154] Nonwoven fabrics

[0155] The nonwoven fabric of the present disclosure is generally a sheet-like structure having two outer surfaces, the nonwoven fabric comprising a plurality of fibers. As used herein and unless otherwise specified, the "outer surface" of a nonwoven fabric refers to the surface of the sheet-like structure, Figure 2denoted as 100 and 101 in the figure. Nonwoven fabrics generally refer to an arrangement of fibers bonded to each other, wherein the fibers are neither woven nor knitted. In general, a plurality of fibers may be arranged in any orientation. In an embodiment, a plurality of fibers are randomly arranged (i.e., without a certain orientation). In an embodiment, a plurality of fibers are arranged in a unidirectional orientation. In an embodiment, a plurality of fibers are arranged in a bidirectional orientation. In some embodiments, a plurality of fibers are in multiple directions and have different arrangements in different regions of the nonwoven fabric. In an embodiment, the nonwoven fabric may include a single type of water-soluble fiber. In an embodiment, the nonwoven fabric may include a single type of non-water-soluble fiber. In an embodiment, the nonwoven fabric may include a single type of water-soluble fiber and one or more different types of non-water-soluble fibers. In an embodiment, the nonwoven fabric may include one or more different types of water-soluble fibers and one or more different types of non-water-soluble fibers. In an embodiment, the nonwoven fabric may consist of water-soluble fibers or consist essentially of water-soluble fibers. In an embodiment, the nonwoven fabric may consist of non-water-soluble fibers or consist essentially of non-water-soluble fibers. In some embodiments, nonwoven fabrics may include not only a single type of fiber-forming material (that is, all fibers have the same fiber-forming material), but may also include fibers prepared by one or more fiber-forming processes, such as wet cooling gel spinning, thermoplastic fiber spinning, melt-blown, spunbond or a combination thereof. In some embodiments, nonwoven fabrics may include a single type of fiber-forming material and the fiber is made by a single fiber-forming process. In some embodiments, nonwoven fabrics may include two or more fiber-forming materials (such as fiber blends of fiber-forming materials with different compositions, fibers including fiber-forming material blends, or both) and the fiber may be prepared by one or more fiber-forming processes, such as wet cooling gel spinning, thermoplastic fiber spinning, melt-blown, spunbond or a combination thereof. In some embodiments, nonwoven fabrics may include two or more fiber-forming materials and the fiber is made by a single fiber-forming process. In an embodiment, the fiber of nonwoven fabrics may have substantially the same diameter or different diameters.

[0156] In embodiments where the nonwoven fabric of the present disclosure includes a blend of water-soluble fibers (including a first water-soluble fiber and a second water-soluble fiber), the first and second water-soluble fibers may be different in diameter, length, tenacity, shape, rigidity, elasticity, solubility, melting point, glass transition temperature (Tg), and / or g ), fiber-forming material, color, or a combination thereof. In embodiments where the nonwoven fabric of the present disclosure comprises a blend of water-insoluble fibers (including a first water-insoluble fiber and a second water-insoluble fiber), the first and second water-insoluble fibers may differ in diameter, length, tenacity, shape, rigidity, elasticity, solubility, melting point, glass transition temperature, fiber-forming material, color, or a combination thereof.

[0157] In general, nonwoven fabrics can be characterized by the average degree of hydrolysis of the polyvinyl alcohol fiber forming material used to make the nonwoven fabric fibers. If the nonwoven fabric is composed of a single fiber type, the degree of hydrolysis of the nonwoven fabric is the same as the degree of hydrolysis of the single fiber type. In an embodiment, the nonwoven fabric of the present disclosure may include a fiber blend, wherein various fibers have different degrees of hydrolysis. In such cases, the degree of hydrolysis of the nonwoven fabric is the arithmetic weighted average of the degrees of hydrolysis of individual fiber types. In an embodiment in which the nonwoven fabric is layered to prepare a nonwoven article, the degree of hydrolysis of the nonwoven article is the arithmetic weighted average of the degrees of hydrolysis of individual fabric layers. In an embodiment in which the nonwoven fabric or article will be used for wicking (e.g., a wearable article in which liquid is drawn away from the user's skin), the fabric or article may have an average degree of hydrolysis in the range of about 95-99.9%, about 96-99%, or about 97-98%. In embodiments where the nonwoven fabric or article is to be used for liquid absorption capacity (e.g., a paper towel for cleaning spills), the fabric or article may have an average degree of hydrolysis in the range of about 93-97%, about 94-96%, or about 95%, and may additionally be bonded with airflow, rather than calender bonding. As shown in the examples below, when a nonwoven fabric of similar composition is bonded with airflow, the liquid absorption capacity is significantly increased compared to a calender bonded nonwoven fabric. The airflow bonded nonwoven fabric includes a thermoplastic fiber material of 5 wt.% or less (based on the total fiber weight) to facilitate bonding. Without wishing to be limited by theory, it is believed that the higher the degree of bonding of the nonwoven fabric, the lower the liquid absorption capacity. Therefore, it is further believed that bonding conditions may be selected to increase the liquid absorption capacity of a nonwoven fabric prepared from a specified fiber type. Without wishing to be limited by theory, it is believed that airflow bonding provides a nonwoven fabric that is more absorbent than calender bonding, and that the absorption capacity decreases as the residence time of the calender bonded nonwoven fabric increases.

[0158] Nonwoven fabric manufacturing method

[0159] The nonwoven fabric of the present disclosure can be prepared from fibers using any method known in the art. As known in the art, when fibers are spunbonded or meltblown, the fibers are continuously laid down to form a nonwoven fabric and then the fibers are bonded.

[0160] In order to provide a nonwoven fabric, the staple fibers can be combed or air-laid and bonded. The methods of combing and air-laying are well known in the art. In addition, as known in the art, since the strength of the combed fabric in the machine direction is typically greater than the horizontal direction due to the orientation of the fibers during combing, the combing process typically uses two doffer cylinders to provide a double-layer combed fabric, the combed fabric having a first layer with a first strength in the horizontal direction and a second layer with a second strength in the horizontal direction, to give additional strength to the entire combed nonwoven fabric in the horizontal direction. As used herein and unless otherwise specified, the term "combed nonwoven fabric" encompasses single-layer combed nonwoven fabrics and multi-layer (e.g., two layers, three layers, etc.) combed nonwoven fabrics. Therefore, it should be understood that when using such double-layer combed nonwoven fabrics as the layer in the composite material article of the present disclosure, the double-layer combed nonwoven fabric is considered as a single layer. As is known in the art, air laying is similar to carding, but in which the fibers are blown by a cylinder onto a conveyor belt or drum using a vacuum, and air laid nonwovens generally have no directionality in fiber alignment due to air turbulence. As a result, air laid nonwovens generally have equal strength in the machine and cross directions.

[0161] Nonwoven fabric bonding methods are well known in the art. Generally speaking, bonding can include thermal bonding, mechanical bonding and / or chemical bonding. Thermal bonding can include, but is not limited to, calendaring, embossing, air flow and ultrasonic. Mechanical bonding can include, but is not limited to, hydroentanglement (hydroentanglement), needle punching and stitch bonding. Chemical bonding can include, but is not limited to, solvent bonding and resin bonding.

[0162] Thermal bonding is usually achieved by applying heat and pressure, and typically maintains the pore size, shape and orientation produced by the carding / melt spinning process. The thermal bonding conditions can be easily determined by a person skilled in the art. In general, if the applied heat and / or pressure is too low, the bonding of the fibers is insufficient to form a self-standing fabric and if the heat and / or pressure is too high, the fibers begin to weld together. The fiber chemistry determines the upper and lower limits of the heat and / or pressure used for thermal bonding. Without wishing to be limited by theory, it is believed that at temperatures above 235°C, polyvinyl alcohol-based fibers degrade. Calender bonding, also known as thermal point bonding in the art, is the use of an engraved calender and a smooth reverse roll to locally apply heat and pressure to form a film-like reinforcement structure throughout the nonwoven fabric. Calendering can be used with nonwoven fabrics formed by any of the methods disclosed herein. In general, calendered melt-spun nonwoven fabrics have a typical bonding area of ​​about 10-25% of the surface of the nonwoven fabric and calendered carded nonwoven fabrics have a typical bonding area of ​​about 20% or more. The bonding point arrangement can be hexagonal, rectangular, etc., and each point of the bonding pattern can be a shape such as a rhombus and an ellipse. It is recognized in the art that elliptical bonding makes the bonding area smoother and the strength increases. The embossing method for fiber thermal bonding is known. Embossing can be single-sided embossing or double-sided embossing. Typically, the embossing of water-soluble fibers includes single-sided embossing using a single embossing roller, which is composed of an ordered circular array and a steel roller with a flat surface. As embossing increases (e.g., as surface features are imparted to the fabric), the surface area of ​​the fabric increases. Without wishing to be limited by theory, it is expected that as the fabric surface area increases, the solubility of the fabric increases. Therefore, changing the surface area by embossing can advantageously adjust the dissolution characteristics of the nonwoven fabric.

[0163] Air-through bonding generally requires high thermoplastic content and two materials with different melting points in the nonwoven fabric. In air-through bonding, the nonwoven fabric is rotated around a drum while hot air flows from the outside of the drum to the center of the drum. Air-through bonding can provide low density and high basis weight (e.g., greater than 20 to about 2000 g / m2) of nonwoven fabric. 2 ) Nonwoven fabrics bonded by air bonding are typically very soft.

[0164] Hydroentanglement is also known in the art as spunlace or jet belting, and achieves bonding by contacting a nonwoven fabric with an array of high-pressure water jets that physically entangle the fibers of the nonwoven fabric. Nonwoven fabrics bonded by hydroentanglement are typically soft and have cloth-like properties, can have high elongation in the cross-machine direction, can have high strength in the machine direction, and contain no chemical adhesives and no embossing as a result of thermal bonding.

[0165] Chemical bonding generally includes solvent bonding and resin bonding. Specifically, chemical bonding typically utilizes a binder solution of a solvent and a resin (e.g., latex or waste polymer left when preparing the fiber). Nonwoven fabrics can be coated with a binder solution and heat and pressure are applied to solidify the binder and bond the nonwoven fabric. The binder solution can be applied as follows: the nonwoven fabric is immersed in a binder solution bath, the binder solution is sprayed on the nonwoven fabric, the binder solution is extruded onto the fabric (foam bonding) and / or the binder solution is applied in a printing or gravure printing mode.

[0166] Chemical bonding can produce smaller, less ordered pores relative to the pores produced by combing / melt spinning. Without wishing to be limited by theory, it is believed that if the resin solution for chemical bonding has sufficient concentration and / or sufficient pressure is applied, a non-porous water-dispersible nonwoven fabric can be formed. The solvent used for chemical bonding induces partial dissolution of the existing fibers in the fabric to weld and bond the fibers together. Therefore, in general, the solvent used for chemical bonding can be any solvent that can at least partially dissolve one or more fiber-forming materials of the nonwoven fabric fibers. In an embodiment, the solvent is selected from the group consisting of: water, ethanol, methanol, DMSO, glycerol and a combination thereof. In an embodiment, the solvent is selected from the group consisting of water, glycerol and a combination thereof. In an embodiment, the adhesive solution comprises a solvent selected from the group consisting of water, ethanol, methanol, DMSO, glycerol and a combination thereof, and further comprises a resin selected from the group consisting of polyvinyl alcohol, latex and polyvinyl pyrrolidone. The adhesive provided in the solution helps the welding process to provide a mechanically more stable fabric. The temperature of the polymer solution is not particularly limited and can be provided at room temperature (about 23°C).

[0167] In some embodiments, the second layer of fibers can be used to bond the nonwoven fabric. In an embodiment, at least one nonwoven layer of a composite article of the present disclosure is bonded using a second layer of nonwoven fabric / fibers. In an embodiment, at least two nonwoven layers of a composite article of the present disclosure are bonded using another layer of nonwoven fabric / fibers. In an embodiment, at least one nonwoven layer of a composite article of the present disclosure is bonded using thermal bonding, mechanical bonding, or chemical bonding alone or in addition to bonding using another layer of nonwoven fabric / fibers.

[0168] Basis Weight / Porosity

[0169] Nonwoven fabrics can be characterized by basis weight. The basis weight of a nonwoven fabric is the mass per unit area of ​​a nonwoven fabric. As known in the art, basis weight can be modified by changing manufacturing conditions. The nonwoven fabric can have the same basis weight before bonding and after bonding. Alternatively, the bonding method can change the basis weight of the nonwoven fabric. For example, in the case of bonding by applying heat and pressure, the thickness of the nonwoven fabric can be reduced (and thereby reducing the area of ​​the nonwoven fabric), thereby increasing the basis weight. Therefore, as used herein and unless otherwise specified, the basis weight of a nonwoven fabric refers to the basis weight of the nonwoven fabric after bonding.

[0170] The nonwoven fabrics of the present disclosure may generally have any basis weight within the following ranges: about 0.1 g / m 2 About 700g / m 2 , about 0.5g / m 2 About 600g / m 2 , about 1g / m 2 About 500g / m 2 , about 1g / m 2 About 400g / m 2 , about 1g / m 2 About 300g / m 2 , about 1g / m 2 About 200g / m 2 , about 1g / m 2 About 100g / m 2 , about 30g / m 2 About 100g / m 2 , about 20g / m 2 About 100g / m 2 , about 20g / m 2 About 80g / m 2 , or about 25g / m 2 About 70g / m 2 .

[0171] In an embodiment, the nonwoven fabric can be carded and have a thickness of about 5 g / m 2 About 15g / m 2 , about 7g / m 2 About 13g / m 2 , about 9g / m 2 About 11g / m 2 , or about 10g / m 2 In an embodiment, the nonwoven fabric can be carded and can have a basis weight of 30 g / m 2 or greater basis weight, e.g. 30 g / m 2 About 70g / m 2 , about 30g / m2 About 60g / m 2 , about 30g / m 2 About 50g / m 2 , about 30g / m 2 About 40g / m 2 , or about 30g / m 2 About 35g / m 2 In an embodiment, the nonwoven fabric may be melt-spun and have a basis weight of about 1 g / m 2 About 20g / m 2 , about 2g / m 2 About 15g / m 2 , about 3g / m 2 About 10g / m 2 , about 5g / m 2 About 15g / m 2 , about 7g / m 2 About 13g / m 2 , about 9g / m 2 About 11g / m 2 or about 10g / m 2 In an embodiment, the nonwoven fabric may be melt-spun and may have a basis weight of about 0.1 g / m 2 About 10g / m 2 , about 0.1g / m 2 About 8g / m 2 , about 0.2g / m 2 About 6g / m 2 , about 0.3g / m 2 About 4g / m 2 , about 0.4g / m 2 About 2g / m 2 or about 0.5g / m 2 About 1g / m 2 The basic weight.

[0172] Related to the basis weight is the fiber volume density and porosity of the nonwoven fabric. The nonwoven fabric that has been prepared and before bonding generally has a fiber density of about 30% by volume or less, that is, for a nonwoven fabric of a specified volume, 30% or less of the volume is composed of fibers and the remaining volume is air. Therefore, the porosity of the nonwoven fabric is generally high. The fiber volume density and porosity of the nonwoven fabric are inversely related characteristics of the nonwoven fabric, for example, a nonwoven fabric with a fiber volume density of about 30% by volume will have a porosity of about 70% by volume. It is well understood in the art that as the fiber volume density increases, the porosity decreases. The fiber volume density can be increased by increasing the basis weight of the nonwoven fabric, such as by applying heat and pressure to achieve bonding, thereby potentially reducing the thickness of the nonwoven fabric (and thereby reducing the volume). Therefore, as used herein and unless otherwise specified, the fiber volume density and porosity of the nonwoven fabric refer to the fiber volume density and porosity of the nonwoven fabric after bonding.

[0173] The nonwoven fabrics of the present disclosure can generally have any porosity in the range of about 50% to about 95%, for example, at least about 50%, at least about 60%, at least about 70%, at least about 75%, or at least about 80% and up to about 95%, up to about 90%, up to about 85%, up to about 80%, up to about 75%, up to about 70%, or any porosity in the range of about 50% to about 95%, about 50% to about 80%, about 50% to about 70%, about 60% to about 75%, about 60% to about 80%, about 60% to about 90%, about 75% to about 85%, about 75% to about 90%, or about 75% to about 95%.

[0174] Pore ​​size can be determined using high magnification and ordered surface analysis techniques including, but not limited to, Brunauer-Emmett-Teller theory (BET), small angle X-ray scattering (SAXS), and molecular adsorption.

[0175] Nonwoven fabrics of the present disclosure can have any thickness generally.Suitable thickness can include, but is not limited to, about 5 to about 10,000 μm (1 cm), about 5 to about 5,000 μm, about 5 to about 1,000 μm, about 5 to about 500 μm, about 200 to about 500 μm, about 5 to about 200 μm, about 20 to about 100 μm, or about 40 to about 90 μm, or about 50 to 80 μm, or about or about 60 to 65 μm, such as 50 μm, 65 μm, 76 μm or 88 μm.Nonwoven fabrics of the present disclosure can be characterized as high loft or low loft.In general, loft refers to the ratio of thickness to basis weight.High loft nonwoven fabrics can be characterized by the high ratio of thickness to basis weight.As used herein, "high loft" refers to that nonwoven fabrics of the present disclosure have a basis weight as defined herein and a thickness exceeding 200 μm. The thickness of nonwoven fabric can be measured according to ASTM D5729-97, ASTM D5736 and ISO 9073-2:1995 and can include, for example, applying a 2N load to the nonwoven fabric and measuring the thickness. High loft material can be used according to methods known in the art, such as air-guided bonding or cross-lapping, and cross-lapping is to use a cross-lapping machine to fold the unbonded fabric itself to establish loft and basis weight. Without wishing to be limited by theory, compared with the water-soluble film in which the film solubility can depend on the thickness of the film, it is not believed that the solubility of the nonwoven fabric comprising water-soluble fibers depends on the thickness of the fabric. In this regard, it is believed that the surface area provided by individual fibers is higher than that of water-soluble films, so regardless of the thickness of the film, the parameter that limits water to approach the fibers and then limits the dissolution of the fibers in the water-soluble nonwoven fabric is the basis weight.

[0176] The water solubility of the nonwoven fabric of the present disclosure is generally related to the type of fiber used to prepare the fabric and the basic weight of the nonwoven fabric. Without wishing to be limited by theory, it is believed that the solubility characteristic curve of the nonwoven fabric follows the same solubility characteristic curve of the fiber used to prepare the nonwoven fabric, and the solubility characteristic curve of the fiber generally follows the same solubility characteristic curve of the fiber-forming polymer. For example, for a nonwoven fabric comprising PVOH fibers, the degree of hydrolysis of the PVOH polymer can be selected so that the water solubility of the nonwoven fabric is also affected. In general, at a given temperature, as the degree of hydrolysis of the PVOH polymer increases from partial hydrolysis (88% DH) to complete hydrolysis (≥98% DH), the water solubility of the polymer generally decreases. Therefore, in one option, the nonwoven fabric is soluble in cold water. For (vinyl acetate vinyl alcohol) copolymers that do not include any other monomers (e.g., not copolymerized with anionic monomers), cold water soluble fabrics that are soluble in water at temperatures less than 10°C may include PVOH fibers having a degree of hydrolysis in the range of about 75% to about 90%, or in the range of about 80% to about 90%, or in the range of about 85% to about 90%. In another option, the nonwoven fabric is soluble in hot water. For (vinyl acetate vinyl alcohol) copolymers that do not include any other monomers (e.g., not copolymerized with anionic monomers), hot water soluble fabrics that are soluble in water at a temperature of at least about 60°C may include PVOH fibers having a degree of hydrolysis of at least about 98%.

[0177] PVOH modification generally increases the solubility of the PVOH polymer. Therefore, it is expected that at a given temperature, the solubility of a nonwoven fabric made from a PVOH copolymer will be higher than that of a nonwoven fabric made from a PVOH homopolymer, which has the same degree of hydrolysis as the PVOH copolymer. Following these trends, water-soluble nonwoven fabrics with specific solubility characteristics can be designed by blending the polymers within the fiber and / or the fibers within the nonwoven fabric.

[0178] Incorporating non-water-soluble fibers into non-woven fabrics can also be used to design non-woven fabrics with specific solubility and / or delayed decomposition (for example, when non-woven fabrics are incorporated into flushable paper towels). Without wishing to be limited by theory, it is believed that when the weight percentage of non-water-soluble fibers contained in the non-woven fabric increases (based on the total weight of the non-woven fabric), the solubility of the non-woven fabric is generally reduced and the stability of the flushable wet wipes is increased, thereby preventing decomposition and maintaining the flushing ability of the paper towel while in use. After contact with water at a temperature at or above the dissolution temperature of the water-soluble fibers, the non-woven fabric containing water-soluble fibers and non-water-soluble fibers begins to disperse as the water-soluble fibers dissolve, thereby decomposing the fabric structure and / or increasing the porosity of the non-woven fabric. Similarly, the delayed decomposition and / or dissolution of the non-woven fabric of the present disclosure can be achieved using a blend of water-soluble fibers with different dissolution characteristics and / or different dissolution temperatures. In embodiments in which the non-woven fabric includes water-soluble fibers and non-water-soluble fibers, the ratio of soluble fibers to non-soluble fibers is not particularly limited. The water-soluble fiber may account for about 1% to about 99% by weight, about 20% to about 80% by weight, about 40% to about 90% by weight, about 50% to about 90% by weight, or about 60% to about 90% by weight of the total fiber weight, and the water-insoluble fiber may account for about 1% to about 99% by weight, about 20% to about 80% by weight, about 10% to about 60% by weight, about 10% to about 50% by weight, or about 10% to about 40% by weight of the total fiber weight.

[0179] Additionally, for water-soluble nonwoven fabrics, if the fiber composition remains constant, then as the fabric basis weight increases, the dissolution rate of the fabric decreases because there is more material to dissolve. For example, at a given temperature, it is expected that a fabric comprising PVOH polymer and having a fiber weight of, for example, 40 g / m 2 The dissolution rate ratio of the water-soluble nonwoven fabric prepared by the fiber of the basic weight is, for example, 30 g / m 2 The basis weight of an otherwise water-soluble nonwoven fabric of the same weight dissolves more slowly. Therefore, the basis weight can also be used to adjust the solubility characteristics of the nonwoven fabric. The nonwoven fabric can generally have any basis weight within the following range: about 1 g / m 2 About 700g / m 2 , about 1g / m 2 About 600g / m 2 , about 1g / m 2 About 500g / m 2 , about 1g / m 2 About 400g / m 2 , about 1g / m 2 About 300g / m 2 , about 1g / m 2 About 200g / m 2 , about 1g / m2 About 100g / m 2 , about 30g / m 2 About 100g / m 2 , about 20g / m 2 About 100g / m 2 , about 20g / m 2 About 80g / m 2 , or about 25g / m 2 About 70g / m 2 .

[0180] Without wishing to be bound by theory, it is believed that the solubility of a water-soluble nonwoven fabric (in terms of time to achieve complete dissolution) is expected to exceed the solubility of a water-soluble film of the same size (L×W) and / or mass made from the same PVOH polymer. This is due to the higher surface area found in the nonwoven fabric than in the film, resulting in faster dissolution.

[0181] Mechanical properties

[0182] As is well understood in the art, the term machine direction (MD) refers to the direction in which a fabric travels when a nonwoven fabric is produced (e.g., on commercial nonwoven fabric manufacturing equipment). Likewise, the term cross direction (CD) refers to the direction in the plane of the fabric that is perpendicular to the machine direction. With respect to nonwoven composite articles, tissues, absorbent articles, or other articles comprising nonwoven composite articles of the present disclosure, the terms refer to the corresponding direction of the article with respect to the nonwoven fabric used to produce the article.

[0183] The toughness of nonwoven fabric can be the same or different from the toughness of the fiber used to prepare the fabric. Without wishing to be limited by theory, it is believed that the toughness of nonwoven fabric is related to the strength of nonwoven fabric, wherein higher toughness provides higher strength to nonwoven fabric. In general, the toughness of nonwoven fabric can be adjusted using fibers with different toughness. Processing can also affect the toughness of nonwoven fabric. In general, nonwoven fabric of the present disclosure can have relatively high toughness, that is, nonwoven fabric is a self-supporting fabric, which can be used as a separate material for preparing articles and / or bags. In an embodiment, nonwoven fabric is a self-supporting fabric. In contrast, nonwoven fabrics prepared according to meltblowing, electrospinning and / or spin spinning processes typically have low toughness, and may not be self-supporting or can be used as a separate fabric for forming articles or bags. Therefore, in some embodiments, nonwoven fabric is not self-supporting and is used in combination with a second nonwoven fabric.

[0184] In an embodiment, the nonwoven fabric of the present disclosure has a ratio of tenacity in the machine direction to tenacity in the cross direction (MD:CD) in the range of about 0.5 to about 1.5, about 0.75 to about 1.5, about 0.80 to about 1.25, about 0.90 to about 1.1, or about 0.95 to about 1.05, or about 1. In an embodiment, the nonwoven fabric of the present disclosure has a MD:CD tenacity ratio of about 0.8 to about 1.25. In an embodiment, the nonwoven fabric of the present disclosure has a MD:CD tenacity ratio of about 0.9 to about 1.1. In an embodiment, the tenacity of the nonwoven fabric of the present disclosure is about 1. Without wishing to be bound by theory, it is believed that when the MD:CD tenacity ratio approaches 1, the durability of the nonwoven fabric increases, thereby resisting the nonwoven fabric from decomposing when stress is applied to the nonwoven fabric during use (e.g., wiping with a flushable tissue containing the nonwoven fabric of the present disclosure, or moving while wearing a wearable absorbent article causing the nonwoven fabric to pull / drag).

[0185] In general, the nonwoven fabrics of the present disclosure have a rougher surface than a water-soluble film, thereby reducing the contact between the surface and the nonwoven fabric compared to the contact between the surface and the water-soluble film. Advantageously, this surface roughness results in a reduced coefficient of kinetic friction and a resulting reduced ratio of the coefficient of static friction to the coefficient of kinetic friction of the nonwoven fabric relative to similar films, improved consumer feel (i.e., a softer cloth-like feel rather than a rubbery feel), and / or improved aesthetics (i.e., less gloss than a water-soluble film). Thus, the fibers should be sufficiently rough to provide surface roughness to the resulting nonwoven fabric without being so rough as to cause drag.

[0186] Auxiliary ingredients

[0187] The present disclosure may include additives and / or treatment agents. When incorporated into a nonwoven fabric, the additives and treatment agents may be dispersed throughout the fabric, such as between fibers, or applied to one or more surfaces of the nonwoven fabric. The additives may be added to the nonwoven fabric during a melt spinning process, which, as is well known in the art, uses a "co-forming" process developed by Kimberly Clark. The auxiliary and treating agents may include, but are not limited to, plasticizers, plasticizer extenders, surfactants, lubricants, mold release agents, fillers, extenders, crosslinking agents, anti-caking agents, antioxidants, anti-adhesive agents, defoaming agents, nanoparticles (e.g., layered silicate nanoclays (e.g., sodium montmorillonite)), bleaching agents (e.g., sodium metabisulfite, sodium bisulfite, or others), repellents (e.g., bittering agents (e.g., denatonium salts, such as denatonium benzoate, denatonium sugars, and denatonium chloride; sucrose octaacetate; quinine; flavonoids, such as quercetin and naringenin; and carotenoids, such as bitters and strychnine) and pungents (e.g., capsaicin, piperine, allyl isothiocyanate, and resin fluoxetine), as well as other functional ingredients, in amounts appropriate for their intended purpose. Specific such auxiliary and treating agents may be selected from those formulations suitable for water-soluble fibers, or those formulations suitable for water-soluble films.

[0188] In an embodiment, nonwoven fabric includes plasticizer.Plasticizer, when included in / on nonwoven fabric, can be any plasticizer described herein or its combination, for example, in conjunction with fiber use of the present disclosure.The total amount of included nonaqueous plasticizer can be in the following ranges with the nonwoven fabric gross weight: about 1wt.% to about 45wt.%, or about 5wt.% to about 45wt.%, or about 10wt.% to about 40wt.%, or about 20wt.% to about 30wt.%, about 1wt.% to about 4wt.%, or about 1.5wt.% to about 3.5wt.%, or about 2.0wt.% to about 3.0wt.%, for example about 1wt.%, about 2.5wt.%, about 5wt.%, about 10wt.%, about 15wt.%, about 20wt.%, about 25wt.%, about 30wt.%, about 35wt.% or about 40wt.%.

[0189] In an embodiment, the nonwoven fabric includes a surfactant. When the surfactant is incorporated into / on the nonwoven fabric, it can be any surfactant described herein or a combination thereof, for example, in conjunction with the fibers of the present disclosure. In various embodiments, based on the total weight of the nonwoven fabric, a surfactant in the range of about 0.01wt.% to about 2.5wt.%, about 0.1wt.% to about 2.5wt.%, about 1.0wt.% to about 2.0wt.%, about 0.01wt% to 0.25wt%, or about 0.10wt% to 0.20wt% can be provided.

[0190] In an embodiment, the nonwoven fabric of the present disclosure is substantially free of auxiliaries. As used herein and unless otherwise specified, "substantially free of auxiliaries" means that the nonwoven fabric includes less than about 0.01 wt.%, less than about 0.005 wt.%, or less than about 0.001 wt.% of auxiliaries based on the total weight of the nonwoven fabric.

[0191] In embodiments, the water-dispersible nonwoven fabric may be colored, tinted, and / or dyed to provide an improved aesthetic effect (relative to a water-soluble film). Suitable colorants may include indicator dyes, such as pH indicators (e.g., thymol blue, bromothymol, thymolphthalein, and thymolphthalein), moisture / water indicators (e.g., water-discoloring inks or leuco dyes), or thermochromic inks, wherein the color of the ink changes when the temperature is increased and / or decreased. Suitable colorants include, but are not limited to, triphenylmethane dyes, azo dyes, anthraquinone dyes, perylene dyes, indigo dyes, food, drug, and cosmetic (FD&C) colorants, organic pigments, inorganic pigments, or combinations thereof. Examples of colorants include, but are not limited to, FD&C Red #40; Red #3; FD&C Black #3; Black #2; mica-based pearlescent pigments; FD&C Yellow #6; Green #3; Blue #1; Blue #2; titanium dioxide (food grade); brilliant black; and combinations thereof.

[0192] When included in the water-soluble fibers, colorants can be provided in amounts of 0.01% to 25% by weight of the water-soluble polymer mixture, for example, 0.02%, 0.05%, 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23% and 24% by weight of the water-soluble polymer mixture.

[0193] Active Agent

[0194] In an embodiment, the nonwoven fabric of the present disclosure may include an activating agent. The activating agent may generally be any activating agent described herein used in conjunction with the fiber of the present disclosure. The activating agent may be added to the nonwoven fabric during the carding of staple fibers, the deposition of continuous fibers, and / or the activating agent may be added to the nonwoven fabric before bonding. The activating agent added to the fiber during carding or deposition may be spread throughout the nonwoven fabric. The activating agent may be added to the nonwoven fabric during the melt-spinning process, which, as is well known in the art, uses the "co-forming" process developed by Kimberly Clark. The activating agent added to the nonwoven fabric after carding or deposition and before or after bonding may be selectively added to one or two surfaces of the nonwoven fabric. In addition, the activating agent may be added to the surface of a tissue, an absorbent article, or other articles prepared by the nonwoven fabric.

[0195] Active agent when present in the nonwoven fabric in an amount in the range of at least about 1wt% or about 1wt% to about 99wt%, provides additional functionality to the nonwoven fabric. In an embodiment, the active agent is selected from the group consisting of: enzymes, oils, spices, colorants, odor absorbents, fragrances, pesticides, fertilizers, oxidants, exfoliants, liquid absorbing materials, activating factors, acid catalysts, metal catalysts, ion scavengers, detergents, disinfectants, surfactants, plasticizers, bleaches, bleaching components, fabric softeners and combinations thereof, as described herein. In an embodiment, the active agent is selected from the group consisting of: enzymes, oils, spices, colorants, odor absorbents, fragrances, pesticides, oxidants, exfoliants, liquid absorbing materials, detergents, disinfectants, surfactants, plasticizers, bleaches, bleaching components, fabric softeners and combinations thereof. In an embodiment, the active agent is selected from the group consisting of: enzymes, oils, odor absorbents, fragrances, exfoliants, liquid absorbing materials, detergents, disinfectants and combinations thereof.

[0196] The activating agent can be solid or liquid. Solid activating agents can have, for example, an average particle size (e.g., Dv50) of at least about 0.01 μm, or a size in the range of about 0.01 μm to about 2 mm. Liquid activating agents can be applied directly to nonwoven fabrics, mixed with carrier powders or microencapsulated. In embodiments comprising carrier powders, the average particle size of the carrier powders can be, for example, at least about 0.01 μm, or in the range of about 0.01 μm to about 2 mm.

[0197] In one class of embodiments, the active agent is encapsulated to allow controlled release of the active agent. Suitable microcapsules may include or be made of one or more of the following: melamine formaldehyde, polyurethane, urea formaldehyde, polyglucosamine, polymethyl methacrylate, polystyrene, polysulfone, polytetrahydrofuran, gelatin, gum arabic, starch, polyvinyl pyrrolidone, carboxymethyl cellulose, hydroxyethyl cellulose, methyl cellulose, arabinogalactan, polyvinyl alcohol, polyacrylic acid, ethyl cellulose, polyethylene, polymethacrylate, polyamide, poly(ethylene vinyl acetate), cellulose nitrate, silicone, poly(lactide-co-glycolide), paraffin, carnauba wax, spermaceti, beeswax, stearic acid, stearyl alcohol, stearyl glyceride, shellac, cellulose acetate phthalate, zein, and combinations thereof. In one class of embodiments, the microcapsules are characterized by, for example, an average particle size (e.g., Dv50) of at least about 0.1 micron or about 0.1 micron to about 200 microns. In alternative embodiments, the microcapsules may form agglomerates of individual particles, for example where the individual particles have an average particle size of at least about 0.1 microns, or in a range of about 0.1 microns to about 200 microns.

[0198] In the embodiment where the active agent is applied to one or more surfaces of a nonwoven fabric or applied to an article, the active agent can be applied by any suitable means. In one embodiment, one or more fixed powder spray guns are used to direct the active agent powder stream to fabric or article from one or more directions, while the fabric or article is transmitted by means of a belt conveyor through the coating section. In an alternative embodiment, the article is conveyed by suspending the active agent powder in the air. In another alternative embodiment, the article is turned over and mixed in a trough-like device together with the active agent powder. In another embodiment that can be combined with any other embodiment, electrostatic force is used to enhance the attraction between the active agent powder and the article. This type of process is typically based on making the powder particles negatively charged and directing these charged particles to the grounded article. In other alternative embodiments, the active agent powder is applied to the article by a secondary transfer tool (including, but not limited to, a rotating brush in contact with the powder) or by a glove that can transfer the powder from a container to the coating powder of the article. In another embodiment, the active agent powder is applied as follows: the powder is dissolved or suspended in a non-aqueous solvent or a carrier, then atomized and sprayed on the nonwoven fabric or article. In one type of embodiment, the solvent or carrier evaporates subsequently, leaving the activating agent powder. In a class of embodiments, the activating agent powder is applied on the nonwoven fabric or article with accurate dosage. Such embodiments adopt closed system dry lubricant application mechanism, for example the powder applicator PM 700D of PekuTECH. In this process, the activating agent powder is optionally fed to the feed trough of the application mechanism in batches or in a continuous manner. The nonwoven fabric or article is transferred to the conveyor belt of the powder applicator from the output belt of the standard rotary drum bag making machine, wherein the activating agent of controlled dosage is applied on the nonwoven fabric or article.

[0199] The liquid active agent can be applied to the nonwoven fabric or article, for example, by spin casting, spraying a solution (eg, an aerosolized solution), roll coating, flow coating, curtain coating, extrusion, knife coating, and combinations thereof.

[0200] Composite items

[0201] Composite articles of the present disclosure include at least two nonwoven fabric layers. Composite articles of the present disclosure may have a first layer of a first nonwoven fabric, the first nonwoven fabric including a first plurality of fibers having a first diameter; a second layer of a second nonwoven fabric, the second nonwoven fabric including a second plurality of fibers having a second diameter; and a first interface comprising at least a portion of the first nonwoven fabric and at least a portion of the second nonwoven fabric, wherein the portion of the first nonwoven fabric and the portion of the second nonwoven fabric are fused together, and wherein the second diameter is less than the first diameter, and the first plurality of fibers, the second plurality of fibers, or both contain water-soluble polyvinyl alcohol fiber-forming materials. Any nonwoven layer of the composite article may include a water-soluble film laminated thereto. The water-soluble film may be prepared from any polymer described herein as a water-soluble fiber-forming material.

[0202] The composite articles disclosed herein may provide one or more advantages including, but not limited to, increased mechanical strength relative to a nonwoven fabric that is the same as a single layer of a separate composite article, enhanced liquid collection functionality relative to a nonwoven fabric that is the same as a single layer of a separate composite article (e.g., a liquid collection layer of a diaper, or a spill absorbent tissue), and / or enhanced retention of fluids and / or active compositions relative to a nonwoven fabric that is the same as a single layer of a separate composite article (e.g., an active lotion for wet wipes).

[0203] A first interface including at least a portion of the first nonwoven fabric and at least a portion of the second nonwoven fabric is a region of the composite material where the first nonwoven fabric overlaps the second nonwoven fabric and the first plurality of fibers are interwoven with the second plurality of fibers, such as Figure 3 In general, Figure 3 As shown in , the portion of the first nonwoven fabric 201 that forms the first interface 200 is the outer surface of the first nonwoven fabric. In an embodiment, the first interface accounts for 50% or less, 40% or less, 30% or less, 25% or less, 20% or less, 10% or less, 5% or less, 2.5% or less, or 1% or less of the thickness of the first nonwoven fabric. In an embodiment, the first interface accounts for at least 0.1%, at least 0.5%, at least 1%, or at least 5% of the thickness of the first nonwoven fabric. In an embodiment, the first interface accounts for about 0.1% to about 25% of the thickness of the first nonwoven fabric. Generally speaking, as Figure 3As shown in , the portion of the second nonwoven fabric 202 that forms the interface is the outer surface of the second nonwoven fabric. In an embodiment, the interface accounts for 75% or less, 70% or less, 60% or less, 50% or less, 40% or less, 30% or less, 25% or less, 20% or less, or 15% or less of the thickness of the second nonwoven fabric. In an embodiment, the first interface accounts for at least 1%, at least 5%, at least 10%, at least 20%, at least 25%, at least 30% or at least 40% of the thickness of the second nonwoven fabric. In an embodiment, the first interface accounts for about 1% to about 75% of the thickness of the second nonwoven fabric.

[0204] As used herein and unless otherwise specified, two nonwoven fabric layers are "fused" if at least a portion of the fibers of each fabric are bonded to the fibers of another fabric. As described herein, the bonding of fibers includes the entanglement of fibers. Two nonwoven fabric layers can be fused using any suitable method. In an embodiment, a portion of the first nonwoven fabric and a portion of the second nonwoven fabric are fused with heat, with solvent, or both. In an embodiment, a portion of the first nonwoven fabric is fused with a portion of the second nonwoven fabric with heat. Thermal fusion may include the use of heat and / or pressure. In an embodiment, one or both of the two discrete nonwoven fabrics can be heated until the fibers soften, and then the fabrics can be pressed together so that when the fibers cool, at least a portion of the fibers of each fabric are bonded to at least a portion of the fibers of another fabric. In an embodiment, one or both of the first and second nonwoven fabrics can be melt-spun and applied by an in-line process so that the heated soft fibers are directly applied to the pre-formed nonwoven fabric after passing through the die assembly and are fused with the fibers of the pre-formed nonwoven fabric, thereby forming a fused interface. In an embodiment, a portion of the first nonwoven fabric is fused with a portion of the second nonwoven fabric with a solvent. Solvent fusion may include: applying a binder solution to one or two nonwoven fabrics, subsequently contacting the nonwoven fabric so that when dry, at least a portion of the fibers of each fabric are bonded to at least a portion of the fibers of another fabric.Solvent fusion may be carried out as an individual process (comprising two individual fabrics formed in advance) or may adopt an in-line process, wherein a binder solution is applied to a preformed nonwoven fabric and a second nonwoven fabric is formed on a preformed nonwoven fabric by a continuous process.The binder solution for solvent fusion of nonwoven fabrics may be any binder solution described herein about bonding.As used herein and unless otherwise specified, "preformed nonwoven fabric" encompasses formed, but unbonded nonwoven fabrics and formed and bonded nonwoven fabrics.As used herein and unless otherwise specified, "individual nonwoven fabric" encompasses nonwoven fabrics formed by combing or air-laying staple fibers or by a continuous process, and nonwoven fabrics may or may not be bonded.In an embodiment, the melting of two nonwoven fabrics may also be utilized to bond one or two nonwoven fabrics.

[0205] In an embodiment, the first interface is fused with a solvent and the solvent is selected from the group consisting of water, ethanol, methanol, DMSO, glycerol, and combinations thereof. In an embodiment, the first interface is fused with a solvent and the solvent is selected from the group consisting of water, glycerol, and combinations thereof. In an embodiment, the first interface is solvent fused using an adhesive solution comprising polyvinyl alcohol and water, glycerol, or a combination thereof. In an embodiment, the first interface is solvent fused using an adhesive solution comprising polyvinyl alcohol, latex, or a combination thereof, and water, glycerol, or a combination thereof.

[0206] As used herein and unless otherwise specified, if the average fiber diameter of the fibers of the identified type is less than the average fiber diameter of the fibers of the other type identified, the diameter of the fibers of the identified type is "less than" the diameter of the fibers of the other type identified. For example, the fibers of the identified type may have overlapping diameter size distributions relative to the fibers of the other type and still have a smaller diameter as long as the average fiber diameter of the fibers of the identified type is less than the average fiber diameter of the fibers of the other type. In an embodiment, the average fiber diameter of the smaller fiber type is less than the smallest diameter in the diameter size distribution of the larger fiber type. There is a difference in diameter, which can be visualized using projection microscope imaging as outlined in ISO137:2015. In an embodiment, the difference in diameter between the smaller fiber type and the larger fiber type can be submicron, for example when multiple melt-spun layers are used. In an embodiment, the diameter difference between the smaller fiber type and the larger fiber type can be about 1 micron to about 300 microns, about 5 microns to about 300 microns, about 5 microns to about 250 microns, about 5 microns to about 200 microns, about 10 microns to about 150 microns, about 10 microns to about 100 microns, about 10 microns to about 90 microns, about 15 microns to about 80 microns, about 15 microns to about 70 microns, about 20 microns to about 60 microns, about 20 microns to about 50 microns, or about 25 microns to about 45 microns. In an embodiment, the diameter difference between the smaller fiber type and the larger fiber type can be about 5 microns to about 75 microns. In an embodiment, the diameter difference between the smaller fiber type and the larger fiber type can be about 20 microns to about 80 microns. Without wishing to be limited by theory, it is believed that providing a composite material of two nonwoven fabrics (wherein the nonwoven fabrics are fused together and the fiber diameter of the second nonwoven fabric is less than that of the first nonwoven fabric) can advantageously improve the adsorption / absorption rate and fluid capacity of the composite material article, improve the direct adsorption / absorption from larger diameter fibers to smaller diameter fibers to preferentially move fluid; increase the surface area to volume ratio of the nonwoven composite material article compared to a single diameter material, thereby increasing the load capacity; and / or improve the dispersion and / or total solubility of the nonwoven composite material article compared to a nonwoven fabric with a single diameter material. The average fiber diameter in the individual fabric layers can be any diameter provided herein. In an embodiment, the first plurality of fibers in the first layer of the first nonwoven fabric can have a diameter of about 10 microns to about 300 microns, about 50 microns to about 300 microns, or about greater than about 100 microns to about 300 microns. In an embodiment, the first plurality of fibers can have an average diameter of greater than about 100 microns to about 300 microns. In an embodiment where the nonwoven layer of the nonwoven composite material includes a blend of fiber types having different diameters, if the fiber diameter distribution is unimodal, the average fiber diameter refers to the average fiber diameter of the blend. The fiber diameter distribution of the blend of each type of fiber in the nonwoven layer is bimodal or more modal.When the diameter distribution of the fiber blend is bimodal or more, when the average fiber diameter of one fiber is less than the average of the smallest diameter distribution of the blend fibers, the fiber has a smaller diameter than the fibers of the blend, and when the average fiber diameter of one fiber is greater than the average of the larger diameter distribution of the blend fibers, the fiber is larger than the fibers of the blend.

[0207] In an embodiment, the composite material article further comprises the third layer of the third nonwoven fabric, and the third nonwoven fabric comprises the third plurality of fibers. In the embodiment in which the nonwoven composite material article comprises the third layer of the third nonwoven fabric, the second layer can be arranged between the first layer and the third layer and at least the second portion of the second nonwoven fabric can be fused with at least a portion of the third nonwoven fabric, thereby providing a second interface. The second interface comprising at least the second portion of the second nonwoven fabric and at least a portion of the third nonwoven fabric is a composite material region in which the second nonwoven fabric overlaps with the third nonwoven fabric and the second plurality of fibers are woven together with the third plurality of fibers. In certain embodiments, according to the thickness of the second layer of the second nonwoven fabric, the first plurality of fibers and the third plurality of fibers can be interwoven and / or fused together, so that there is no clear boundary between the first interface and the second interface. In general, the part of the second nonwoven fabric forming the second interface is the outer surface of the second nonwoven fabric, and the outer surface is opposite to the outer surface of the second nonwoven fabric fused with the first nonwoven fabric. In an embodiment, the second interface accounts for 75% or less, 70% or less, 60% or less, 50% or less, 40% or less, 30% or less, 25% or less, 20% or less, or 15% or less of the thickness of the second nonwoven fabric. In an embodiment, the second interface accounts for at least 1%, at least 5%, at least 10%, at least 20%, at least 25%, at least 30% or at least 40% of the thickness of the second nonwoven fabric. In an embodiment, the second interface accounts for about 1% to about 75% of the thickness of the second nonwoven fabric. In an embodiment, the portion of the third nonwoven fabric that forms the second interface is the outer surface of the third nonwoven fabric. In an embodiment, the second interface accounts for 50% or less of the thickness of the third nonwoven fabric, 40% or less, 30% or less, 25% or less, 20% or less, 10% or less, 5% or less, 2.5% or less, or 1% or less of the thickness of the first nonwoven fabric. In embodiments, the second interface comprises at least 0.1%, at least 0.5%, at least 1%, or at least 5% of the thickness of the third nonwoven textile. In embodiments, the second interface comprises from about 0.1% to about 25% of the thickness of the third nonwoven textile.

[0208] In an embodiment, the second portion of the second nonwoven fabric and a portion of the third nonwoven fabric are fused with heat, fused with a solvent, or both. In an embodiment, the second portion of the second nonwoven fabric and a portion of the third nonwoven fabric are fused with heat. In an embodiment, the second portion of the second nonwoven fabric and a portion of the third nonwoven fabric are fused with a solvent.

[0209] In an embodiment, the second interface is fused with a solvent and the solvent is selected from the group consisting of water, ethanol, methanol, DMSO, glycerol, and combinations thereof. In an embodiment, the second interface is fused with a solvent and the solvent is selected from the group consisting of water, glycerol, and combinations thereof. In an embodiment, the second interface is solvent fused using an adhesive solution comprising polyvinyl alcohol and water, glycerol, or a combination thereof. In an embodiment, the second interface is solvent fused using an adhesive solution comprising polyvinyl alcohol, latex, or a combination thereof, and water, glycerol, or a combination thereof.

[0210] In an embodiment, the first layer of the first nonwoven fabric and the second layer of the second nonwoven fabric have different porosities. As used herein and unless otherwise specified, when the porosity difference of the nonwoven fabric is at least about 1%, the two nonwoven fabrics have "different porosities". In an embodiment, the porosity difference between the two nonwoven fabric layers in the composite material article can be about 1% to about 20%. For example, a nonwoven fabric layer in the composite material article can have a porosity of about 80%, and the second nonwoven fabric layer in the composite material article can have a porosity of about 85%, and the porosity difference is 5%. In an embodiment, the porosity of the second nonwoven fabric is less than the porosity of the first nonwoven fabric. In an embodiment, the porosity of the second nonwoven fabric is the same as the porosity of the first nonwoven fabric. As used herein and unless otherwise specified, if the porosity value difference between the two nonwoven fabrics is less than 1%, the two nonwoven fabrics have "same porosity".

[0211] In embodiments where the composite material article comprises a third layer of a third nonwoven fabric, the third nonwoven fabric may have a porosity that is the same as or different from that of the first nonwoven fabric. In embodiments, the third nonwoven fabric may have a porosity that is the same as that of the first nonwoven fabric. In embodiments, the third nonwoven fabric may have a porosity that is different from that of the first nonwoven fabric. In embodiments, the porosity of the third nonwoven fabric may be less than that of the first nonwoven fabric. In embodiments, the third nonwoven fabric may have a porosity that is the same as that of the second nonwoven fabric. In embodiments, the third nonwoven fabric may have a porosity that is different from that of the second nonwoven fabric. In embodiments, the porosity of the third nonwoven fabric may be less than that of the second nonwoven fabric. In embodiments, the porosity of the second nonwoven fabric may be less than that of the first nonwoven fabric, and the porosity of the third nonwoven fabric may be less than that of the second nonwoven fabric. In embodiments, the nonwoven composite material article may have a porosity gradient between layers of nonwoven fabrics, wherein one outer surface of the composite material structure may have a maximum porosity, and another outer surface of the composite material structure may have a minimum porosity. In an embodiment, the composite structure may have a porosity gradient between layers of the nonwoven fabric, wherein the outer surface of the composite structure may have the greatest porosity, and the middle layer of the composite structure may have the least porosity. In an embodiment, the composite structure may include a fourth or higher layer of nonwoven fabric, such that the middle layer may include the second and third layers of the nonwoven fabric (for a four-layer composite structure), or the third layer of the nonwoven fabric (for a five-layer composite structure).

[0212] Without wishing to be bound by theory, it is believed that when the porosity of the composite structure comprises a gradient, the composite structure advantageously enhances the wicking of liquid from the high porosity outer surface to the low porosity outer surface or low porosity intermediate layer.

[0213] The plurality of fibers in any given nonwoven layer of the composite article may be any of the fibers disclosed herein and may be the same or different. In embodiments, the composition of the fiber-forming materials in the first plurality, second plurality, and third plurality of fibers may be the same or different, for example in terms of diameter, length, tenacity, shape, rigidity, elasticity, solubility, melting point, glass transition temperature (T g), fiber-forming materials, colors, or combinations thereof. The following table presents composite articles under consideration, wherein the nonwoven layer may include fibers having three different fiber compositions, wherein each letter "A", "B", and "C" refers to a specific fiber composition and "-" means that the composite article under consideration does not include a third layer of nonwoven fabric. Each of the fiber compositions A, B, and C may be (a) a single fiber type including a single fiber-forming material; (b) a single fiber type including a blend of fiber-forming materials; (c) a blend of each type of fiber, each type of fiber including a single fiber-forming material; (d) a blend of each type of fiber, each type of fiber including a blend of fiber-forming materials; or (e) a blend of each type of fiber, each type of fiber including a single fiber-forming material or a blend of fiber-forming materials.

[0214]

[0215] In an embodiment, the first plurality of fibers include a water-soluble polyvinyl alcohol fiber-forming material. In an embodiment, the second plurality of fibers include a water-soluble polyvinyl alcohol fiber-forming material. In an embodiment, the first plurality of fibers and the second plurality of fibers include a water-soluble polyvinyl alcohol fiber-forming material. In an embodiment comprising a third layer of a nonwoven fabric having a third plurality of fibers, the third plurality of fibers may include a water-soluble polyvinyl alcohol fiber-forming material. In an embodiment, the polyvinyl alcohol fiber-forming material may be present in a plurality of fibers in one or more fiber types. The water-soluble polyvinyl alcohol fiber-forming material of any one of the first plurality, the second plurality, or the third plurality of fibers may be any water-soluble polyvinyl alcohol fiber-forming material disclosed herein. In an embodiment in which two or more of the first plurality of fibers, the second plurality of fibers, and / or the third plurality of fibers include a polyvinyl alcohol fiber-forming material, the polyvinyl alcohol in the various plurality of fibers may be the same or different, the polyvinyl alcohol in the various plurality of fibers may be a separate fiber-forming material or a part of a fiber-forming material blend, and if the various plurality of fibers include different polyvinyl alcohol fiber-forming materials, the diameter, length, toughness, shape, rigidity, elasticity, solubility, melting point, glass transition temperature (T g ), fiber forming materials, colors or combinations thereof may differ. In an embodiment, the water-soluble polyvinyl alcohol fiber forming material comprises a polyvinyl alcohol homopolymer, a polyvinyl alcohol copolymer or a combination thereof. In an embodiment, the polyvinyl alcohol comprises a copolymer and the copolymer may be an anion-modified polyvinyl alcohol. In an embodiment, the polyvinyl alcohol comprises an anion-modified polyvinyl alcohol and the anion-modified polyvinyl alcohol comprises (alkyl) acrylate-modified polyvinyl alcohol, maleate-modified polyvinyl alcohol, sulfonate-modified polyvinyl alcohol or a combination thereof.

[0216] In an embodiment, the fibers in the first plurality of fibers, the second plurality of fibers, and / or the third plurality of fibers may include a water-soluble fiber-forming material other than a polyvinyl alcohol fiber-forming material. In an embodiment, the fibers in the first plurality of fibers, the second plurality of fibers, and / or the third plurality of fibers may include a blend of water-soluble fiber-forming materials, the blend including a polyvinyl alcohol fiber-forming material and a water-soluble fiber-forming material other than a polyvinyl alcohol fiber-forming material. In an embodiment, the water-soluble fiber-forming material other than the polyvinyl alcohol fiber-forming material may include polyacrylate, polyvinyl pyrrolidone, polyethylene imine, guar gum, gum arabic, gum tannin, carrageenan, water-soluble starch, water-soluble cellulose, cellulose ether, cellulose ester, cellulose amide, or a combination thereof. In an embodiment, the first plurality of fibers include a water-soluble fiber-forming material selected from the group consisting of polyacrylate, polyvinyl pyrrolidone, polyethylene imine, guar gum, gum arabic, gum tannin, carrageenan, water-soluble starch, water-soluble cellulose, cellulose ether, cellulose ester, cellulose amide, and a combination thereof. In an embodiment, the second plurality of fibers comprises a water-soluble fiber-forming material selected from the group consisting of: polyacrylates, polyvinyl pyrrolidone, polyethylene imine, guar gum, gum arabic, tannin gum, carrageenan, water-soluble starch, water-soluble cellulose, cellulose ether, cellulose ester, cellulose amide, and combinations thereof. In an embodiment, the third plurality of fibers comprises a water-soluble fiber-forming material selected from the group consisting of: polyacrylates, polyvinyl pyrrolidone, polyethylene imine, guar gum, gum arabic, tannin gum, carrageenan, water-soluble starch, water-soluble cellulose, cellulose ether, cellulose ester, cellulose amide, and combinations thereof.

[0217] In an embodiment, the fibers in the first plurality of fibers, the second plurality of fibers, and / or the third plurality of fibers may include a water-insoluble fiber-forming material disclosed herein. In an embodiment, the water-insoluble fiber-forming material may include cellulose, cotton, jute, flax, ramie, sisal, bagasse, banana fiber, flower bark, silk, tendon, gut, wool, algae fiber, mohair, angora wool, cashmere, collagen, actin, nylon, polyester, rayon, bamboo fiber, modal fiber, diacetate fiber, triacetate fiber, polypropylene, polycarbonate, polybutylene terephthalate, polyethylene terephthalate, polyamide, thermoplastic polyurethane, elastic polypropylene, rayon, or a combination thereof. In an embodiment, the water-insoluble fiber-forming material includes cellulose. In an embodiment, the non-water-soluble fiber-forming material includes cellulose, cotton, jute, flax, ramie, sisal, bagasse, banana fiber, tamarisk, silk, tendon, gut, wool, algae fiber, mohair, angora wool, cashmere, collagen, actin, nylon, polyester, rayon, bamboo fiber, modal fiber, diacetate fiber, triacetate fiber, polypropylene, polycarbonate, polybutylene terephthalate, polyethylene terephthalate, polyamide, thermoplastic polyurethane, elastic polypropylene, rayon or a combination thereof.

[0218] For the first, second, and third plurality of fibers, as well as any additional plurality of fibers provided in the composite material, for example when the composite article includes additional nonwoven layers (i.e., fourth layer, fifth layer, etc.), the following embodiments are contemplated:

[0219]

[0220] In an embodiment, the first plurality of fibers include a single type of fiber. In an optimization of the aforementioned embodiment, the single type of fiber includes a single fiber-forming material selected from water-soluble polyvinyl alcohol fiber-forming materials, water-soluble fiber-forming materials other than polyvinyl alcohol, and a non-water-soluble fiber-forming material. In another optimization, the single type of fiber includes a blend of fiber-forming materials, which includes two or more of the following: water-soluble polyvinyl alcohol fiber-forming materials, water-soluble fiber-forming materials other than polyvinyl alcohol, non-water-soluble fiber-forming materials, and combinations thereof. In an embodiment, the first plurality of fibers include a blend of fibers. In an embodiment, the first plurality of fibers include a single fiber type, and the single fiber type includes a fiber-forming material selected from the group consisting of: polyvinyl alcohol homopolymers, polyvinyl alcohol copolymers, and combinations thereof.

[0221] In an embodiment, the second plurality of fibers include a single type of fiber. In the optimization of the aforementioned embodiment, the single type of fiber includes a single fiber-forming material selected from water-soluble polyvinyl alcohol fiber-forming materials, water-soluble fiber-forming materials other than polyvinyl alcohol, and non-water-soluble fiber-forming materials. In another optimization, a single type of fiber includes a blend of fiber-forming materials, which includes two or more of the following: water-soluble polyvinyl alcohol fiber-forming materials, water-soluble fiber-forming materials other than polyvinyl alcohol, non-water-soluble fiber-forming materials, and combinations thereof. In an embodiment, the second plurality of fibers include a blend of fibers. In an embodiment, the second plurality of fibers include a single fiber type, and the single fiber type includes a water-soluble fiber-forming material. In the optimization of the aforementioned embodiment, the water-soluble fiber-forming material includes a water-soluble polyvinyl alcohol fiber-forming material, a water-soluble fiber-forming material other than polyvinyl alcohol, or a combination thereof. In an embodiment, the second plurality of fibers include a single fiber type, and the single fiber type includes a non-water-soluble fiber-forming material. In an embodiment, the second plurality of fibers include a blend of fiber types, and at least one of the blends of fiber types includes a water-soluble fiber-forming material.

[0222] In an embodiment, the third plurality of fibers include a single type of fiber. In the optimization of the aforementioned embodiment, the single type of fiber includes a unique fiber-forming material selected from water-soluble polyvinyl alcohol fiber-forming materials, water-soluble fiber-forming materials other than polyvinyl alcohol, and non-water-soluble fiber-forming materials. In another optimization, the single type of fiber includes a blend of fiber-forming materials, which includes two or more of the following: water-soluble polyvinyl alcohol fiber-forming materials, water-soluble fiber-forming materials other than polyvinyl alcohol, non-water-soluble fiber-forming materials, and combinations thereof. In an embodiment, the third plurality of fibers include a blend of fibers. In an embodiment, the third plurality of fibers include a single fiber type, and the single fiber type includes a fiber-forming material selected from the group consisting of: polyvinyl alcohol homopolymers, polyvinyl alcohol copolymers, and combinations thereof. In an embodiment, the third plurality of fibers include a blend of fiber types. In an embodiment, the third plurality of fibers are the same as the first plurality of fibers.

[0223] In an embodiment, the first plurality of fibers, the second plurality of fibers, the third plurality of fibers, or a combination thereof, comprises a natural fiber-forming material, a plant-based fiber-forming material, a bio-based fiber-forming material, a biodegradable fiber-forming material, a compostable fiber-forming material, or a combination thereof.

[0224] In an embodiment, the first nonwoven fabric has a toughness ratio (MD:CD) of about 0.5 to about 1.5. In an embodiment, the first nonwoven fabric has a MD:CD of about 0.8 to about 1.25. In an embodiment, the first nonwoven fabric has a MD:CD of about 0.9 to about 1.1. In an embodiment, the second nonwoven fabric has a toughness ratio (MD:CD) of about 0.5 to about 1.5. In an embodiment, the second nonwoven fabric has a MD:CD of about 0.8 to about 1.25. In an embodiment, the second nonwoven fabric has a MD:CD of about 0.9 to about 1.1. In an embodiment, the third nonwoven fabric has a toughness ratio (MD:CD) of about 0.5 to about 1.5. In an embodiment, the third nonwoven fabric has a MD:CD of about 0.8 to about 1.25. In an embodiment, the third nonwoven fabric has a MD:CD of about 0.9 to about 1.1. In an embodiment, the toughness ratio (MD:CD) of the nonwoven composite article is in the range of about 0.5 to about 1.5, about 0.8 to about 1.25, about 0.9 to about 1.1 or about 0.95 to about 1.05. In an embodiment, the MD:CD of the nonwoven composite article is about 0.8 to about 1.5. In an embodiment, the MD:CD of the nonwoven composite article is about 0.9 to about 1.1. The MD:CD of the nonwoven composite article is related to the MD:CD ratio of each individual layer of nonwoven fabric present in the composite article. Without wishing to be limited by theory, it is believed that the MD:CD of the composite article cannot be determined by considering the MD and CD of each layer of nonwoven fabric separately, but the MD and CD of the nonwoven composite article must be measured. Without wishing to be limited by theory, it is believed that as the toughness ratio MD:CD of the nonwoven composite article approaches 1, the durability of the composite article increases, providing excellent resistance to the nonwoven fabric rupture when stress is applied to the nonwoven fabric during use. Furthermore, without wishing to be bound by theory, it is believed that a composite article including at least one layer of a spunmelt nonwoven fabric will have an MD:CD ratio closer to 1:1 than an identical composite article except that it includes all carded layers.

[0225] In an embodiment, the first plurality of fibers, the second plurality of fibers, the third plurality of fibers, or a combination thereof comprise bicomponent fibers. In an embodiment, the first plurality of fibers comprise bicomponent fibers. In an embodiment, the second plurality of fibers comprise bicomponent fibers. In an embodiment, the third plurality of fibers comprise bicomponent fibers. In an embodiment, the first and second plurality of fibers comprise bicomponent fibers. In an embodiment, the first and third plurality of fibers comprise bicomponent fibers. In an embodiment, the second and third plurality of fibers comprise bicomponent fibers. In an embodiment, the first, second, and third plurality of fibers comprise bicomponent fibers. In an embodiment wherein the first, second, and / or third plurality of fibers comprise bicomponent fibers, the bicomponent fibers may comprise a core of a fiber-forming material surrounded by a sheath of a fiber-forming material, wherein for a given water temperature, the sheath fiber-forming material has a higher solubility in water than the core fiber-forming material.

[0226] In an embodiment, the first plurality of fibers, the second plurality of fibers, the third plurality of fibers, or a combination thereof include a plasticizer, a surfactant, or a combination thereof. In an embodiment, the nonwoven composite article of the present disclosure includes an active agent, an absorbent material, or a combination thereof. In the optimization of the aforementioned embodiment, the first plurality of fibers, the second plurality of fibers, the third plurality of fibers, or a combination thereof include an active agent, an absorbent material, or a combination thereof. In an embodiment, the nonwoven composite article of the present disclosure includes an active agent, which includes an enzyme, an oil, a fragrance, a colorant, an odor absorbent, a fragrance, an insecticide, a fertilizer, an oxidant, an activator, an acid catalyst, a metal catalyst, an ion scavenger, a detergent, a disinfectant, a surfactant, a bleach, a bleaching component, a fabric softener, or a combination thereof. In an embodiment, the nonwoven composite article of the present disclosure includes an active agent, which includes an enzyme, an oil, a colorant, an odor absorbent, a fragrance, an insecticide, an oxidant, a ion scavenger, a detergent, a disinfectant, a surfactant, a bleach, a bleaching component, a fabric softener, or a combination thereof. In embodiments, the nonwoven composite article of the present disclosure includes an active agent including oils, colorants, odor absorbers, fragrances, ion scavengers, disinfectants, or combinations thereof. In embodiments where the nonwoven composite article includes a fragrance, the fragrance may be encapsulated.

[0227] The nonwoven fabric layer of the composite material article can generally be prepared using any method described herein. In some embodiments, the first layer of the first nonwoven fabric can be a combed layer. In an embodiment, the second layer of the second nonwoven fabric can be a melt-spun layer. In an embodiment, the first layer includes a combed layer and the second layer includes a melt-spun layer. In an embodiment, the first layer can be a combed layer and the second layer can be a melt-blown layer. In an embodiment, the first layer can be a combed layer and the second layer can be an air-laid layer. In an embodiment, the first layer can be a combed layer, which includes fibers containing polyvinyl alcohol fiber-forming materials, and the second layer can be a melt-blown layer, which includes fibers containing low molecular weight polyvinyl alcohol homopolymers with a viscosity of about 5 cP or less. In an embodiment, the first layer can be a combed layer, which includes fibers containing polyvinyl alcohol fiber-forming materials, and the second layer can be an air-laid layer, which includes cellulose fibers. In an embodiment, the third layer can be a combed layer or a melt-spun layer. In an embodiment, the third layer can be a combed layer. In an embodiment, the third layer can be a melt-blown layer. In an embodiment, the first layer can be a combed layer, the second layer can be a melt-spun layer, and the third layer can be a combed layer. In an embodiment, the first layer may be a carded layer, the second layer may be an airlaid layer, and the third layer may be a meltspun layer.

[0228] The basis weight of the nonwoven composite article of the present disclosure is not particularly limited and can be between about 5 g / m 2 About 150g / m 2 , about 5g / m2 About 125g / m 2 , about 5g / m 2 About 100g / m 2 , about 5g / m 2 About 70g / m 2 , about 5g / m 2 About 50g / m 2 , about 5g / m 2 About 30g / m 2 In an embodiment, the basis weight of the nonwoven composite article of the present disclosure may be about 5 g / m 2 About 50g / m 2 In an embodiment, the basis weight of the nonwoven composite article of the present disclosure may be about 50 g / m 2 About 150g / m 2 In an embodiment, the basis weight of the first layer of nonwoven fabric may be about 30 g / m 2 About 70g / m 2 , and the basis weight of the nonwoven composite article may be about 60 g / m 2 About 150g / m 2 In an embodiment, the basis weight of the first layer of nonwoven fabric may be about 5 g / m 2 About 15g / m 2 In an embodiment, the basis weight of the first layer of nonwoven fabric may be about 5 g / m 2 About 15g / m 2 , and the basis weight of the nonwoven composite article can be about 15 g / m 2 About 50g / m 2 In an embodiment, the basis weight of the third layer of nonwoven fabric may be about 5 g / m 2 About 15g / m 2 In an embodiment, the basis weight of the first layer of nonwoven fabric may be about 5 g / m 2 About 15g / m 2 , and the basis weight of the third layer of nonwoven fabric may be about 5 g / m 2 About 15g / m 2. In an embodiment, the second layer of nonwoven fabric may be included in the composite article at about 2.5 wt.% to about 10 wt.%, based on the total weight of the composite article. In an embodiment, the second layer of nonwoven fabric may be included in the composite article at about 2.5 wt.% to about 10 wt.%, based on the total weight of the composite article, and the first layer of nonwoven fabric may be included in the composite article at about 90 wt.% to about 97.5 wt.%, based on the total weight of the composite article. In an embodiment, the second layer of nonwoven fabric may be included in the composite article at about 2.5 wt.% to about 10 wt.%, based on the total weight of the composite article, and the first layer of nonwoven fabric and the third layer of nonwoven fabric together are included at about 90 wt.% to about 97.5 wt.%, based on the total weight of the composite article. In an embodiment, the third layer of nonwoven fabric may be included in the composite article at about 2.5 wt.% to about 10 wt.%, based on the total weight of the composite article, and the first layer of nonwoven fabric and the second layer of nonwoven fabric together are included at about 45 wt.% to about 48 wt.%, based on the total weight of the composite article.

[0229] In an embodiment, the fiber diameter of the first plurality of fibers may be substantially uniform. In an embodiment, the fiber diameter of the second plurality of fibers may be substantially uniform. In an embodiment, the fiber diameter of the third plurality of fibers may be substantially uniform. In an embodiment, the fiber diameter of the first plurality of fibers and the third plurality of fibers may be substantially uniform. In an embodiment, the fiber diameter of each of the first plurality of fibers, the second plurality of fibers, and the third plurality of fibers may be substantially uniform.

[0230] In general, the tenacity of the first plurality of fibers, the second plurality of fibers, and / or the third plurality of fibers can be 3 cN / dtex to about 10 cN / dtex, optionally about 3 cN / dtex to about 5 cN / dtex, about 4 cN / dtex to about 7 cN / dtex, about 7 cN / dtex to about 10 cN / dtex, about 4 cN / dtex to about 8 cN / dtex, about 5 cN / dtex to about 8 cN / dtex, or about 6 cN / dtex to about 8 cN / dtex. In an embodiment, the tenacity of the first plurality of fibers, the second plurality of fibers, and / or the third plurality of fibers can be 4 cN / dtex to 8 cN / dtex. In an embodiment, the tenacity of the first plurality of fibers, the second plurality of fibers, and / or the third plurality of fibers can be about 6 cN / dtex to about 8 cN / dtex. In an embodiment, the tenacity of the first plurality of fibers, the second plurality of fibers, and / or the third plurality of fibers can be about 3 cN / dtex to about 5 cN / dtex. In embodiments, the tenacity of the first plurality of fibers may range from about 4 cN / dtex to about 8 cN / dtex.In embodiments where the plurality of fibers comprises a blend of fiber types, the tenacity of the fiber blend is an arithmetic weighted average of the tenacities of each fiber type.

[0231] In an embodiment, the nonwoven composite article may have an improved modulus, tensile strength, elongation, toughness, or a combination thereof in the machine direction, the cross direction, or both, relative to the same article comprising only the first layer. In an embodiment, the nonwoven composite article may have an improved modulus, tensile strength, elongation, toughness, or a combination thereof in the machine direction, relative to the same article comprising only the first layer. In an embodiment, the nonwoven composite article may have an improved modulus, tensile strength, elongation, toughness, or a combination thereof in the cross direction, relative to the same article comprising only the first layer. In an embodiment, the nonwoven composite article may have an improved modulus, tensile strength, elongation, toughness, or a combination thereof in the cross direction, relative to the same article comprising only the first layer.

[0232] Method for making composite material article

[0233] Generally speaking, composite articles can be made using any process known in the art suitable for combining two or more layers of nonwoven fabrics such that at least a portion of a first layer is fused to a portion of a second layer, thereby forming an interface.

[0234] In an embodiment, a method of forming a nonwoven composite article of the present disclosure may include the following steps:

[0235] (a) depositing a second layer comprising a second nonwoven fabric on a first layer comprising a first nonwoven fabric under conditions sufficient to fuse at least a portion of the first nonwoven fabric to at least a portion of the second nonwoven fabric, thereby forming a first interface; and

[0236] (b) optionally, depositing a third layer comprising a third nonwoven fabric on the second layer comprising the second nonwoven fabric under conditions sufficient to fuse at least a second portion of the second nonwoven fabric to at least a portion of the third nonwoven fabric, thereby forming a second interface.

[0237] In embodiments, steps (a) and (b) may be repeated to include additional non-woven layers into the composite structure, such as a fourth non-woven layer, a fifth non-woven layer, and so forth.

[0238] Generally, conditions sufficient to fuse at least a portion of the first nonwoven fabric to at least a portion of the second nonwoven fabric and / or to fuse at least a second portion of the second nonwoven fabric to at least a portion of the third nonwoven fabric may include thermal and / or solvent fusing as described herein.

[0239] In an embodiment, thermal fusion includes contacting a portion of the first nonwoven fabric with a portion of the second nonwoven fabric, contacting a second portion of the second nonwoven fabric with a portion of the third nonwoven fabric, or both when one or more portions of the nonwoven fabric to be fused are in a softened state. In an embodiment, thermal fusion includes contacting a portion of the first nonwoven fabric with a portion of the second nonwoven fabric when the second nonwoven fabric is in a heated state. In an embodiment, contacting a portion of the first nonwoven fabric with a portion of the second nonwoven fabric when the second nonwoven fabric is in a heated state includes forming fibers of the second nonwoven fabric in an online process and depositing fibers of the second nonwoven fabric on the first nonwoven fabric, so that the fibers of the second nonwoven fabric are deposited after extrusion through a die assembly, followed by cooling and / or quenching. In an embodiment, thermal fusion includes contacting a second portion of the second nonwoven fabric with a portion of the third nonwoven fabric when the second nonwoven fabric is in a heated state. In an embodiment, contacting the second portion of the second nonwoven fabric with the portion of the third nonwoven fabric while the second nonwoven fabric is in a heated state includes forming fibers of the second nonwoven fabric in an online process and depositing the fibers of the second nonwoven fabric on the first nonwoven fabric, such that the fibers of the second nonwoven fabric are deposited after being extruded through a die assembly, followed by cooling and / or quenching, and then depositing the third nonwoven fabric on the second layer of the still heated nonwoven fabric, followed by cooling and / or quenching the second nonwoven fabric.

[0240] In an embodiment, solvent fusion includes applying a solvent to a portion of the first nonwoven fabric, a portion of the second nonwoven fabric, or both, and then depositing the second nonwoven fabric on the first nonwoven fabric, thereby forming a first interface. In an embodiment, solvent fusion includes applying a solvent to a second portion of the second nonwoven fabric, a portion of the third nonwoven fabric, or both, and then depositing the third nonwoven fabric on the second nonwoven fabric, thereby forming a second interface. In an embodiment, solvent fusion includes applying a solvent to a portion of the first nonwoven fabric, and then depositing the second nonwoven fabric. In an embodiment, solvent fusion includes applying a solvent to a second portion of the second nonwoven fabric, and then depositing the third nonwoven fabric. The solvent for solvent fusion can be any solvent or adhesive solution disclosed herein for solvent fusion and chemical bonding. In an embodiment, the portion of the first nonwoven fabric, the portion of the second nonwoven fabric, the second portion of the second nonwoven fabric, the portion of the third nonwoven fabric, or a combination of the foregoing are at least partially soluble in a solvent. In an embodiment, the solvent includes water, glycerol, or a combination thereof. In an embodiment, solvent fusion further includes applying pressure after depositing the second and / or third nonwoven fabric layer.

[0241] In an embodiment of the foregoing method, the first layer may include a carded nonwoven fabric. In an embodiment of the foregoing method, the third layer may include a carded nonwoven fabric or a spunmelt nonwoven fabric. In an embodiment of the foregoing method, the second layer may include a spunmelt nonwoven fabric or an air-laid nonwoven fabric. In an embodiment, the first layer may include a carded nonwoven fabric, the second layer may include a spunmelt nonwoven fabric, and the third layer may include a carded nonwoven fabric. In an embodiment, the first layer may include a carded nonwoven fabric, the second layer may include a meltblown nonwoven fabric, and the third layer may include a carded nonwoven fabric. In an embodiment, the second layer may include an air-laid nonwoven fabric. In an embodiment, the first layer may include a carded nonwoven fabric, the second layer may include an air-laid nonwoven fabric, and the third layer may include a spunmelt nonwoven fabric. In an embodiment, the first layer may include a carded nonwoven fabric, the second layer may include an air-laid nonwoven fabric, and the third layer may include a meltblown nonwoven fabric. In an embodiment, the nonwoven composite article may include five layers of nonwoven fabric, wherein the first layer may include a carded nonwoven fabric, the second layer may include an air-laid nonwoven fabric, the third layer may include a melt-spun nonwoven fabric, the fourth layer may include an air-laid nonwoven fabric, and the fifth layer may include a carded nonwoven fabric. In an embodiment, the nonwoven composite article may include five layers of nonwoven fabric, wherein the first layer may include a carded nonwoven fabric, the second layer may include an air-laid nonwoven fabric, the third layer may include a melt-blown nonwoven fabric, the fourth layer may include an air-laid nonwoven fabric, and the fifth layer may include a carded nonwoven fabric. In an embodiment, the second nonwoven fabric may include a cellulose fiber-forming material.

[0242] Flushable paper towels

[0243] The flushable tissue of the present disclosure comprises, in part, a nonwoven composite article according to the present disclosure.

[0244] As used herein, the term "flushable" refers to nonwoven fabrics, composite articles, or other articles containing nonwoven fabrics or composite articles that are dispersible in aqueous environments, such as liquid sewage systems, so that discarding the fabrics or articles will not cause such articles to become stuck in pipes of plumbing systems or accumulate over time to cause such pipe blockages. Flushable articles have the advantage of being easier to handle in recycling processes, or can simply be flushed in, for example, septic tanks and municipal sewage treatment systems, so that after use, the fabrics or articles do not need to be landfilled, incinerated, or otherwise disposed of.

[0245] The flushable tissue may include a plurality of fibers, wherein the plurality of fibers may include water-soluble fibers and water-insoluble fibers. The water-soluble fibers of the flushable nonwoven fabric may include any of the water-soluble polymers disclosed herein. In an embodiment, the water-soluble fibers include polyvinyl alcohol polymers. In an optimization of the aforementioned embodiment, the water-soluble fibers include PVOH homopolymers. In another optimization of the aforementioned embodiment, the water-soluble fibers include PVOH copolymers. In an embodiment, the water-soluble fibers include a blend of polyvinyl alcohol polymers. In an optimization of the aforementioned embodiment, the water-soluble fibers include one or more PVOH homopolymers. In another optimization of the aforementioned embodiment, the water-soluble fibers include one or more PVOH copolymers. In yet another optimization of the aforementioned embodiment, the water-soluble polymers include one or more PVOH homopolymers and one or more PVOH copolymers.

[0246] In an embodiment, the water-soluble fiber comprises a blend of water-soluble polymers. In an optimization of the aforementioned embodiment, the blend of water-soluble polymers may include a polyvinyl alcohol polymer or a blend of polyvinyl alcohol polymers comprising a polyvinyl alcohol homopolymer, a polyvinyl alcohol copolymer, or a combination thereof. In another optimization, the water-soluble fiber may include a blend of water-soluble polymers including a polyvinyl alcohol homopolymer and a polyvinyl alcohol copolymer.

[0247] In an embodiment, the water-soluble fiber comprises a bicomponent fiber. In the aforementioned optimization, the bicomponent fiber comprises a core / sheath type fiber. Without wishing to be limited by theory, it is believed that the bicomponent fiber can provide stability to the flushable tissue during storage and use due to the composition of the sheath, and provide a readily soluble, degradable or compostable waste product to be disposed of based on the composition of the core.

[0248] In an embodiment, the flushable nonwoven fabric may include a plurality of water-soluble fibers, including a first water-soluble fiber and a second water-soluble fiber, wherein the first and second water-soluble fibers may be different in diameter, length, tenacity, shape, stiffness, elasticity, solubility, melting point, glass transition temperature (Tg), and water-soluble fibers. g ), water-soluble polymers, color, or a combination thereof.

[0249] As previously described, water-insoluble fibers generally include fibers made of any material that does not dissolve in 300 seconds or less at a temperature of 80° C. or less as measured by MSTM-205. Suitable water-insoluble fiber materials include, but are not limited to, cotton, polyester, polyethylene (e.g., high-density polyethylene and low-density polyethylene), polypropylene, wood pulp, fluff pulp, abaca, rayon, polylactic acid, nylon 6, insoluble cellulose, insoluble starch, jute, flax, ramie, sisal, bagasse, banana fiber, tamarisk, silk, tendon, gut, wool, algae fiber, mohair, angora wool, cashmere, collagen, actin, nylon, polyester, rayon, bamboo fiber, modal fiber, diacetate fiber, triacetate fiber, and combinations thereof.

[0250] The amount of water-soluble fibers in the flushable nonwoven fabric can range from about at least about 20, 25, 30, 40, 50 or 60 wt % and / or up to about 90, 85, 80, 75, 70, 60, 50 or 40 wt %, based on the total weight of the flushable nonwoven fabric, for example, about 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85 or 90 wt %, based on the total weight of the flushable nonwoven fabric.

[0251] The amount of water-insoluble fibers in the flushable nonwoven fabric can range from about at least about 5, 10, 15, 20, 40, 50 or 60 wt % and / or up to about 75, 70, 60, 50, 40, 30 or 25 wt %, based on the total weight of the flushable nonwoven fabric, for example, about 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70 or 75 wt %, based on the total weight of the flushable nonwoven fabric.

[0252] The ratio of water-insoluble fibers to water-soluble fibers in the flushable nonwoven fabric can range from about 1:18 to about 4:1, from about 1:10 to about 3:1, from about 1:5 to about 2:1, or from about 1:2 to about 2:1, for example, about 1:18, 1:16, 1:14, 1:12, 1:10, 1:5, 1:3, 1:2, 1:1, 2:1, 3:1, or 4:1.

[0253] Without wishing to be bound by theory, for nonwoven fabrics containing only polyvinyl alcohol fibers, as the flushing ability increases, the mechanical stability decreases. Therefore, the inventors have found that by incorporating water-insoluble fibers into nonwoven fabrics, the flushing ability can still be increased without compromising the mechanical stability of the fabric.

[0254] For flushable nonwoven fabrics including polyvinyl alcohol, flushability increases with increasing water solubility, but water solubility has an inverse relationship with mechanical stability. Therefore, the selection of a specific polyvinyl alcohol and any additional water-soluble and / or water-insoluble fibers may be important for maintaining the mechanical integrity of the fabric while also having suitable flushability. For example, parameters such as DH and modification percentage of the polyvinyl alcohol homopolymer or copolymer may affect the flushability and mechanical properties of the fiber.

[0255] The flushable tissues of the present disclosure may include a cleaning lotion. The flushable tissues of the present disclosure generally include fibers having a surface energy high enough to allow the fibers to be easily wetted by the cleaning lotion during the wetting step of the tissue manufacturing process. Thus, in an embodiment, at least a portion of at least one outer layer of the nonwoven composite article of the flushable tissue includes hydrophilic fibers. In an embodiment, at least a portion of each outer layer of the nonwoven composite article used to prepare the flushable tissue includes hydrophilic fibers.

[0256] Non-limiting examples of applications for the tissues include cleaning surfaces, cleaning skin, automotive applications, baby care, feminine care, hair cleaning and makeup removal or application, skin conditioners, ointments, sunscreens, insect repellents, pharmaceuticals, varnish industrial and institutional cleaning.

[0257] Lotion composition

[0258] The flushable wipes of the present disclosure may include a lotion composition to wet the substrate to aid in cleaning. In embodiments where the flushable wipes are personal care wipes, the lotion composition may also include ingredients that soothe, soften or condition the skin, improve the feel of the lotion, improve the removal of residue from the skin, provide a pleasant scent and / or prevent bacterial growth, for example.

[0259] The pH of the lotion composition can be at or near about 5.5, close to physiological skin pH. The pH of the low pH lotion composition can be at or near about 3.8, and can be suitable for the following situations: paper towels are used to remove alkaline residues, such as residues from fecal matter, and help restore a healthy acidic skin pH of about 5 and / or make irritants from fecal matter non-irritating, such as by inactivating fecal enzymes. Low pH lotions can also inhibit microbial growth. In embodiments where the pH of the lotion composition is about 4 or lower, the fibers of the first plurality of fibers, the second plurality of fibers, and / or the third plurality of fibers can include polyvinyl alcohol copolymers. Copolymers can be provided as the only fiber-forming material in the fibers of a fiber blend, or as a component of the fiber-forming material in the fibers of a blend including a fiber-forming material. In the optimization of the aforementioned embodiment, the fibers can include a blend of polyvinyl alcohol copolymers and homopolymers. The polyvinyl alcohol copolymers and homopolymers can be provided in a ratio of about 1:1 to about 4:1. In the additional optimization of the aforementioned embodiment, the fibers containing polyvinyl alcohol copolymers can be blended with non-water-soluble fibers.

[0260] The lotion composition may comprise a superwetter, a rheology modifier, an emollient and / or an emulsifier. The superwetter may be present in an amount of about 0.01 wt % to 0.2 wt % superwetter relative to the total weight of the lotion composition. The superwetter may be selected from the group consisting of trisiloxanes, polyether polydimethylsiloxanes, wherein the polyether functional group is PEG, PPG or a mixture thereof, and mixtures thereof.

[0261] The rheology modifier may be present in an amount of about 0.01 wt% to 0.5 wt% based on the total weight of the lotion composition.The rheology modifier may be selected from the group consisting of: tri-gum, modified tri-gum, and combinations thereof.

[0262] The emollient, if present, may be a thickening emollient. Suitable emollients include, but are not limited to, PEG-10 sunflower glycerides, sunflower oil, palm oil, olive oil, emu oil, babassu oil, evening primrose oil, palm kernel oil, cod liver oil, cottonseed oil, jojoba oil, meadowfoam seed oil, oil), sweet almond oil, canola oil, soybean oil, avocado oil, safflower oil, coconut oil, sesame oil, rice bran oil, grape seed oil, mineral oil, isopropyl stearate, isostearyl isononanoate, diethylhexyl fumarate, diisostearyl malate, triisocetyl citrate, stearyl stearate, methyl palmitate, methyl heptyl isostearate, paraffin fats, lanolin oil and lanolin wax, long chain alcohols such as cetyl alcohol, stearyl alcohol, behenyl alcohol, isostearyl alcohol and 2-hexyl-decanol, myristyl alcohol, polydimethylsiloxane fluids of various molecular weights and mixtures thereof, PPG-15 stearyl ether (also known as arlatone E), shea butter, olive butter, sunflower butter, coconut butter, jojoba butter, cocoa butter, squalene and squalene, isoparaffins, polyethylene glycols of various molecular weights, polypropylene glycols of various molecular weights or mixtures thereof.

[0263] The emulsifier, if present, may be solid at room temperature. Suitable emulsifiers include, but are not limited to, laureth-23, ceteth-2, ceteth-10, ceteth-20, ceteth-21, ceteareth-20, steareth-2, steareth-10, steareth-20, oleth-2, oleth-10, oleth-20, steareth-100, steareth-21, PEG-40 sorbitan peroleate, PEG-8 stearate, PEG-40 stearate, PEG-50 stearate, PEG-100 stearate, sorbitan peroleate, PEG-60 stearate, PEG-70 stearate, PEG-80 stearate, PEG-90 stearate, PEG-100 stearate, PEG-100 stearate, PEG-200 stearate, PEG-200 stearate, PEG-1 ...100 stearate, PEG-200 stearate, Sorbitan laurate, sorbitan palmitate, sorbitan stearate, sorbitan tristearate, sorbitan oleate, sorbitan trioleate, polysorbate 20, polysorbate 21, polysorbate 40, polysorbate 60, polysorbate 61, polysorbate 65, polysorbate 80, polysorbate 81, polysorbate 85, PEG-40 hydrogenated castor oil, citrate, microcrystalline wax, paraffin wax, beeswax, carnauba wax, ozokerite, cetyl alcohol, stearyl alcohol, cetearyl alcohol, myristyl alcohol, behenyl alcohol, and mixtures thereof.

[0264] In an embodiment, the cleansing lotion comprises an aqueous emulsion including an emollient and an emulsifier.

[0265] The cleaning lotion may further comprise a humectant, including but not limited to glycerin, propylene glycol, and phospholipids; a fragrance, such as essential oils and perfumes described herein; a preservative; an enzyme; a colorant; an oil absorbent; an insecticide; a fertilizer; an activator; an acid catalyst; a metal catalyst; an ion scavenger; a detergent; a germicide; a surfactant; a bleaching agent; a bleaching component; and a fabric softener. In an embodiment, the cleaning lotion comprises a fragrance, a preservative, an enzyme, a colorant, an oil absorbent, an insecticide, an ion scavenger, a detergent, a disinfectant, or a combination thereof.

[0266] Preservatives prevent microbial growth in liquid lotions, flushable tissues, and / or substrates on which tissues are used. Preservatives can be hydrophobic or hydrophilic. Suitable preservatives include, but are not limited to, methylparabens, such as methylparaben, propylparaben, alkyl glycinates, iodine derivatives, and combinations thereof.

[0267] The lotion load can be between 150% and 480%.As used herein, "load" refers to the combination of nonwoven composite material article and lotion composition, that is, lotion composition is loaded on the nonwoven composite material article or wherein, without considering the method for combining the nonwoven composite material article with lotion composition, that is, dipping, spraying, kiss roller coating, etc. "Lotion load" refers to the amount of lotion loaded on the nonwoven composite material article or wherein, and is expressed as the weight of lotion and the ratio of the weight of dry (unloaded) nonwoven composite material article, in percentage. It may be necessary to flush the paper towel load lotion to a certain extent so that some lotions can be easily transferred to substrate (such as skin or another surface to be cleaned) during use. Transfer can contribute to cleaning, provide pleasant sensation (such as smooth skin feeling or cool from evaporation) for the user, and / or allow the transfer of compound to provide beneficial function on substrate.

[0268] Flushable tissue can be a nonwoven composite material article with high-density interstitial space between the fibers constituting the tissue. In order to maintain enough available lotions to transfer to substrates on the tissue surface, a large amount of interstitial spaces in the tissue can be filled with lotions. The lotion in the interstitial space may not be easy to transfer to substrates, so excessive lotion can be loaded into the tissue, and its amount is enough to signal the user that lotion can be used for transferring to substrates, for example, by providing enough moistening sensations. Advantageously, the nonwoven composite material article used in the flushable tissue can have a porosity gradient as described herein, which can contribute to lotion loading into the tissue.

[0269] Flushable paper towels can be manufactured by wetting nonwoven composite material articles with at least 1 gram of liquid cleaning lotion per gram of dry fiber composite material. Suitable methods for delivering cleaning lotion to substrate include, but are not limited to, immersion, spraying, impregnation, extrusion coating and dip coating. After wetting, the wetted composite material articles can be folded, stacked, cut by length and packaged as needed. Flushable paper towels generally have sufficient size to allow convenient disposal, while being small enough to be easily discarded into sewage systems. Wetting composite material articles can be cut or folded into such size during manufacturing process, or the size can be larger and have components such as perforations, to allow users to separate individual paper towels from fabrics with desired size.

[0270] Generally speaking, the nonwoven composite article of the present disclosure can be used for flushable paper towels. In an embodiment, the flushable paper towel of the present disclosure comprises the nonwoven composite article of the present disclosure and a cleaning lotion. In an embodiment, the flushable paper towel of the present disclosure consists of the nonwoven composite article of the present disclosure and a cleaning lotion.

[0271] Absorbent articles

[0272] Nonwoven fabrics and nonwoven composite materials of the present disclosure can be used as the liquid collection layer of absorbent articles.Absorbent articles can include bibs, breast pads, nursing pads, cleaning pads (such as floor cleaning pads), diapers, diaper pants, incontinence pads, pads and other articles (such as adult incontinence diapers, adult incontinence pads, adult incontinence pants, toilet training pads, toilet training pads, toilet training pants and pet training pads, such as puppy pads), interlabial devices, menstrual pads, sanitary pads, sanitary napkins, tampons, spill absorbing pads (spill absorbing mat), spill absorbing pads (spill absorbing pad), spill absorbing rolls, wound dressings, etc. In one aspect, any of the aforementioned articles can be disposable articles. The term "disposable" refers to articles designed to or intended to be discarded after a single use. That is, disposable articles are not intended to be washed or otherwise recovered or reused, and in an embodiment, may not be washed, recovered or reused.

[0273] As used herein, the term "absorbent article" includes articles that absorb and contain body exudates. The term "absorbent article" is intended to include diapers, incontinence articles, sanitary napkins, and the like. The term "incontinence article" is intended to include pads, undergarments (pads held in place by some type of suspension system, such as belts, etc.), inserts for absorbent articles, capacity boosters for absorbent articles, underpants, mattress pads, and the like, regardless of whether they are worn by adults or other incontinent individuals. At least some of such absorbent articles are intended to absorb body fluids, such as menstrual fluid or blood, vaginal discharge, urine, sweat, breast milk, and fecal matter.

[0274] As used herein, "diaper" refers to a device intended to be placed against the skin of the wearer to absorb and contain various exudates discharged from the body. Diapers are generally worn by infants and incontinent individuals around the lower torso so as to surround the waist and legs of the wearer. Examples of diapers include infant or adult diapers and pant-shaped diapers, such as training pants. As used herein, "training pants" refers to disposable garments designed for infants or adult wearers with a waist opening and leg openings. The pants can be placed in the appropriate position on the wearer by inserting the wearer's legs into the leg openings and sliding the pants to a position around the wearer's lower torso. The pants can be preformed by any suitable technology, including (but not limited to) using refixable and / or non-refixable bonding (e.g., seams, welding, adhesives, adhesive bonding, fasteners, etc.) to join parts of the article together. The pants can be preformed anywhere along the circumference of the article (e.g., side fastening, front waist fastening).

[0275] The absorbent article of the present disclosure will generally include a liquid-permeable top sheet, a liquid-impermeable back sheet joined to the top sheet, and a liquid collection layer and an absorbent core between the top sheet and the back sheet. In embodiments where the absorbent article is a wearable article (e.g., an incontinence article, a sanitary napkin, etc.), the article may have a side facing the wearer and a side facing outward. Generally speaking, the liquid-permeable top sheet is on the side facing the wearer, and the liquid-impermeable back sheet is on the side of the absorbent article facing outward. The absorbent core is generally a plate-like structure, and when provided as a wearable, has a side facing the wearer and a side facing outward.

[0276] In general, the liquid-permeable top sheet can be any liquid-permeable top sheet known in the art. For wearable articles, the top sheet can be completely or partially elasticized or can be shortened to provide a void space between the top sheet and the absorbent core. In general, the impermeable back sheet can be any impermeable back sheet known in the art. The back sheet prevents the effluent absorbed by the absorbent core and contained in the article form from contacting any substrate that the absorbent article may contact. The back sheet can be a laminate that is impermeable to liquid and includes a nonwoven fabric and a thin plastic film (such as a thermoplastic film). Suitable back sheet films include those manufactured by Tredegar Industries Inc. of Terre Haute, Ind., Indiana and sold under the trade names X15306, X10962 and X10964. Other suitable back sheet materials can include breathable materials that allow vapor to escape from the absorbent article while still preventing liquid from passing through the back sheet. Exemplary breathable materials can include materials such as woven fabrics, nonwoven fabrics, and composite materials, such as those manufactured by Mitsui Toatsu Chemical Co. of Japan under the name ESPOIR NO and by EXXON Chemical Co. of Bay City, Tex. under the name EXXAIRE.

[0277] The absorbent core is disposed between the top sheet and the back sheet. The absorbent core may comprise any absorbent material generally capable of absorbing and retaining liquids such as urine and other body exudates. The absorbent core may include a wide variety of liquid absorbent materials commonly used in disposable diapers and other absorbent articles, such as superabsorbent polymers, comminuted wood pulp (airfelt), creped cellulose wadding; absorbent foams, absorbent sponges, absorbent gelling materials, or any other known absorbent material or combination of materials. The absorbent core may include small amounts (less than about 10%) of non-liquid absorbent materials, such as adhesives, waxes, oils, and the like.

[0278] Generally speaking, the liquid collection layer includes a nonwoven fabric of the present disclosure, which includes a plurality of fibers comprising a water-soluble polyvinyl alcohol fiber-forming material. The plurality of fibers may include a single fiber type or a blend of fiber types, and the fibers may include a unique polyvinyl alcohol fiber-forming material or a blend of fiber-forming materials including a polyvinyl alcohol fiber-forming material.

[0279] In an embodiment, a collection layer may be disposed between the absorbent core and the top plate. In a wearable embodiment, the collection layer may be disposed on the side of the absorbent core facing the wearer. In an embodiment, the collection layer may be disposed between the absorbent core and the back plate. In a wearable embodiment, the collection layer may be disposed on the side of the absorbent core facing outward. In an embodiment, the collection layer wraps the absorbent core. The collection layer may be a single plate that wraps the absorbent core, or may be provided as two individual layers joined. Without wishing to be limited by theory, it is believed that by including a collection layer between the absorbent core and the back plate or on the side of the absorbent core facing outward, liquid is advantageously prevented from leaking from the absorbent article by providing additional collection material to capture any liquid overflow from the top plate side and / or the side facing the wearer.

[0280] In general, the collection layer may be in direct contact with the absorbent core, may include a space between the absorbent core and the collection layer, or may include an intervening layer between the absorbent core and the collection layer. In an embodiment, the collection layer is in contact with the absorbent core. In an embodiment, the absorbent article includes an intervening layer disposed between the acquisition layer and the absorbent core. In an embodiment, the collection layer is in contact with the absorbent core on the top plate side / the side facing the wearer, and the intervening layer is disposed between the acquisition layer and the absorbent core on the back plate side / the side facing the outside. In an embodiment, the collection layer is in contact with the absorbent core on the back plate side / the side facing the outside, and the intervening layer is disposed between the acquisition layer and the absorbent core on the top plate side / the side facing the wearer. The intervening layer may be, for example, a second liquid-permeable layer or a collection layer, which is included to help promote the diffusion of liquid from the deposition point to cover the full area of ​​the absorbent core.

[0281] In an embodiment, an absorbent article comprises an absorbent core and a collection layer, wherein the collection layer comprises a nonwoven fabric comprising a plurality of fibers comprising a water-soluble polyvinyl alcohol fiber-forming material, and the collection layer comprises a nonwoven composite material article comprising a first layer of nonwoven fabric comprising a first plurality of fibers, a second layer of nonwoven fabric comprising a second plurality of fibers, and an optional third layer of nonwoven fabric, wherein the nonwoven fabric layer, the second layer of nonwoven fabric, and / or the third layer of nonwoven fabric can be a nonwoven fabric comprising a water-soluble polyvinyl alcohol fiber-forming material. In an embodiment, a wearable absorbent article comprises an absorbent core having a side facing the wearer and a side facing the outside, and a collection layer, wherein the collection layer comprises a nonwoven fabric comprising a plurality of fibers comprising a water-soluble polyvinyl alcohol fiber-forming material, and the collection layer comprises a nonwoven composite material article, which comprises a first layer of nonwoven fabric comprising a first plurality of fibers, a second layer of nonwoven fabric comprising a second plurality of fibers, and an optional third layer of nonwoven fabric, wherein the nonwoven fabric layer, the second layer of nonwoven fabric, and / or the third layer of nonwoven fabric can be a nonwoven fabric comprising a water-soluble polyvinyl alcohol fiber-forming material.

[0282] In an embodiment, an absorbent article comprises an acquisition layer which is a nonwoven composite article of the present disclosure. In an embodiment, a wearable absorbent article comprises an acquisition layer which is a nonwoven composite article of the present disclosure.

[0283] In an embodiment, the collection layer can be a single layer of nonwoven fabric as disclosed herein, and the nonwoven fabric layer includes water-soluble polyvinyl alcohol fiber forming material. In an embodiment, the nonwoven composite material article of the present disclosure can be used for the collection layer. In an embodiment, the collection layer includes the nonwoven composite material article of the present disclosure. In an embodiment, the collection layer consists of the nonwoven composite material article of the present disclosure.

[0284] Nonwoven articles containing liquids

[0285] The nonwoven fabric of the present disclosure can be used for nonwoven articles containing liquid. Nonwoven articles containing liquid can be single unit dose articles for accurate administration of liquid including active agent. Liquid including active agent can include, but is not limited to, liquid home care composition, such as laundry detergent, cleaning composition, fabric softener or dishwashing detergent, liquid personal care composition (such as shampoo, shower gel or shaving cream) or non-family, non-personal care composition (such as liquid agricultural products, such as fertilizer and pesticide). Liquid can generally include non-aqueous liquid that will not dissolve nonwoven articles. Suitable liquid includes, but is not limited to, 1,2-propylene glycol, ethanol, glycerine, propylene glycol, dipropylene glycol, methyl propylene glycol and mixtures thereof. Other lower alcohols, low molecular weight polyols, C1-C4 alkanolamines, such as monoethanolamine and triethanolamine can also be used. As used herein, "low molecular weight polyol" is a molecule with more than two hydroxyl groups, and its molecular weight is in the range of 50g / mol and 1000g / mol, 50g / mol to 800g / mol or 50g / mol to 600g / mol. With the gross weight of liquid and activating agent, liquid can be in the range of about 0.1% to about 98%, about 1% to about 75% or about 5% to about 50%, for example, about 10%, about 25%, about 35%, about 40%, about 45%, about 48% or about 50% level. Typically, liquid comprises less than 50% water, less than 25% water, less than 20% water, less than 10% water, less than 5% water or about 0.001% to about 20% water or about 0.001% to about 10% water.

[0286] The active agent in the liquid may include, but is not limited to, one or more of the following groups: enzymes, oils, fragrances, colorants, odor absorbers, aromatics, pesticides, fertilizers, oxidants, activators, acid catalysts, metal catalysts, ion scavengers, detergents, disinfectants, surfactants, bleaching agents, bleaching components, and fabric softeners. In an embodiment, the active agent comprises one or more enzymes and one or more surfactants.

[0287] Advantageously, nonwoven fabric of the present disclosure can absorb and / or be adsorbed into the fiber network and on the fiber surface to provide enough activating agents for unit dose.Nonwoven fabric with absorption / adsorbed onto the liquid composition thereon can be wrapped or otherwise enclosed in the second nonwoven fabric to provide a barrier between the activating agent and the hand of the consumer.Therefore, the nonwoven article containing liquid of the present disclosure can be advantageously disposed by the consumer, and can not pollute the hand or other surfaces of the consumer.Compared with the single unit dose pouch consisting of film for liquid laundry detergent, the nonwoven article containing liquid of the present disclosure can be dissolved faster and more completely than film, because the surface area provided by the fiber of the nonwoven fabric increases.

[0288] Generally, the liquid-containing nonwoven fabric comprises a core nonwoven fabric comprising a first plurality of fibers comprising a first polyvinyl alcohol fiber-forming material, wherein the core nonwoven fabric comprises a liquid comprising an active agent; and an outer nonwoven fabric comprising a second plurality of fibers comprising a second polyvinyl alcohol fiber-forming material, wherein the core nonwoven fabric is enclosed by the outer nonwoven fabric. In an embodiment, the outer nonwoven fabric wraps around the core nonwoven fabric. Figure 4A As shown, the nonwoven fabric can have a machine direction 301 and a cross direction 300. The nonwoven fabric can be wrapped around a core nonwoven fabric 302, for example by folding the nonwoven fabric around an axis, such as along the machine direction ( Figure 4B ). In an embodiment, the outer nonwoven fabric can have the form of a sleeve or an envelope, and the core nonwoven fabric can be provided to the sleeve or envelope. The sleeve or envelope can be prepared by a single nonwoven fabric, such as by folding the fabric in half and sealing the long edge to provide a sleeve structure with two openings, the core nonwoven fabric can be inserted through the opening, or by folding the fabric in half and sealing two of the three edges to form an envelope or pocket structure with an opening, the core nonwoven fabric can be inserted through the opening. The sleeve or envelope can be prepared alternatively by two nonwoven fabrics, the nonwoven fabrics are stacked and sealed along two opposite edges (to form a sleeve) or stacked and sealed along three edges (to form a pocket or envelope). In an embodiment, the core nonwoven fabric and the outer nonwoven fabric have the same length in at least one dimension. For example, in the embodiment in which the outer nonwoven fabric wraps the core nonwoven fabric and the embodiment in which the outer nonwoven fabric is provided as a sleeve, the core nonwoven fabric and the outer nonwoven fabric can have the same length. In contrast, in embodiments where the outer nonwoven fabric is provided as an envelope or pocket, the core nonwoven fabric will necessarily be shorter than the envelope or pocket because three sides of the envelope or pocket are sealed prior to introduction of the core nonwoven fabric.

[0289] In general, the core nonwoven fabric comprises liquid, and liquid comprises activating agent.Before the core nonwoven fabric is exposed to liquid, the dry basis weight of the core nonwoven fabric can be within the range of about 15gsm to about 200gsm, about 20gsm to about 175gsm, about 25gsm to about 150gsm or about 30gsm to about 120gsm.The core nonwoven fabric can be saturated with liquid.In an embodiment, the weight of the core nonwoven fabric comprising liquid is twice to ten times of the weight of the core nonwoven fabric before adding liquid.In an embodiment, the core nonwoven fabric comprises about 5g to about 30g liquid, about 5g to about 25g liquid, about 8g to about 20g liquid, about 8g to about 19g liquid, about 10g to about 19g liquid or about 12g to about 18g liquid. In an embodiment, the liquid weight of the core nonwoven fabric containing liquid is from about 30 gsm to about 2000 gsm, from about 40 gsm to about 1750 gsm, from about 50 gsm to about 1500 gsm, from about 60 gsm to about 1200 gsm, from about 100 gsm to about 1000 gsm, from about 200 gsm to about 800 gsm, or from about 300 gsm to about 600 gsm. That is, the liquid amount of the core nonwoven fabric per square meter is from about 30 g to about 2000 g, from about 40 g to about 1750 g, from about 50 g to about 1500 g, from about 60 g to about 1200 g, from about 100 g to about 1000 g, from about 200 g to about 800 g, or from about 300 g to about 600 g.

[0290] In general, the core nonwoven fabric can comprise a single layer nonwoven fabric or can comprise a multilayer nonwoven fabric (such as a discrete layer or by means of folding stacking), optionally laminated or bonded together. In an embodiment, the core nonwoven fabric, whether it is a single layer or a multilayer nonwoven fabric, can self-fold to provide a thicker core for the nonwoven article containing liquid. The number of times that the core nonwoven fabric can be folded is not particularly limited, and will depend on the required thickness of the nonwoven article containing liquid. In an embodiment, the gross thickness (comprising both outer nonwoven fabric and core nonwoven fabric) of the nonwoven article containing liquid can be about 2mm to about 50mm, about 3mm to about 45mm, about 4mm to about 40mm, about 5mm to about 35mm, about 5mm to about 30mm or about 5mm to about 25mm.

[0291] In general, the outer nonwoven fabric can comprise a single layer nonwoven fabric or can comprise a multilayer nonwoven fabric (for example, a discrete layer or by means of folding and stacking), optionally laminated or bonded together. In an embodiment, the basis weight of the outer nonwoven fabric can be from about 15gsm to about 400gsm, from about 20gsm to about 300gsm, from about 25gsm to about 250gsm, from about 30gsm to about 210gsm or from about 30gsm to about 140gsm. In an embodiment, the thickness of the outer nonwoven fabric can be from about 0.5mm to about 6.0mm, from about 0.75mm to about 4.5mm or from about 1.0mm to about 3.0mm. Advantageously, the basis weight and thickness of the outer nonwoven fabric can be selected to provide a barrier between an activating agent and the environment so that the activating agent will not be contaminated with secondary packaging, a surface or the hand of a consumer. The outer nonwoven fabric also advantageously provides a surface that can be labeled, printed or embossed. In an embodiment, the mark as a mark or description can be printed on the outer nonwoven fabric so that the mark is visible to the consumer. In an embodiment, the outer nonwoven fabric may be embossed with a pattern.The outer nonwoven fabric may be printed, embossed, or otherwise marked before forming the liquid-containing nonwoven article and / or after forming the liquid-containing nonwoven article.

[0292] In general, at least a portion of the core nonwoven fabric may be in contact with at least a portion of the outer nonwoven fabric. In an embodiment, the portion of the core nonwoven fabric in contact with a portion of the outer nonwoven fabric may be an edge or periphery of the core nonwoven fabric, and the portion of the outer nonwoven fabric in contact with a portion of the core nonwoven fabric may be an edge or periphery. In an embodiment, the portion of the core nonwoven fabric in contact with a portion of the outer nonwoven fabric may be sealed or otherwise bonded to the outer nonwoven fabric. In an embodiment, the core nonwoven fabric and the outer nonwoven fabric may be sealed on at least one edge, at least two edges, or at least three edges. In an embodiment, the portion of the core nonwoven fabric in contact with a portion of the outer nonwoven fabric may be a portion of the face of the core nonwoven fabric, and the portion of the outer nonwoven fabric in contact with the core nonwoven fabric may be a portion of the face of the outer nonwoven fabric. In an embodiment, the core nonwoven fabric may fit tightly within the outer nonwoven fabric so that the core nonwoven fabric substantially fills the internal volume formed by the outer nonwoven fabric. As used herein, and unless otherwise specified, the core nonwoven fabric "substantially fills" means that at least 70% of the internal volume formed by the outer nonwoven fabric is occupied by the core nonwoven fabric. In embodiments, the core nonwoven occupies at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 95%, or at least 98% of the interior volume formed by the outer nonwoven.

[0293] In general, the shape and size of the nonwoven fabric containing liquid is not particularly limited. In an embodiment, the size and shape of the nonwoven fabric containing liquid is selected so that the article containing liquid is suitable for the palm of consumer. In an embodiment, the maximum length on any dimension is about 7 inches (17.78cm), about 6 inches (15.24cm), about 5 inches (12.70cm) or about 4 inches (10.16cm). In an embodiment, the maximum length on any dimension is at least about 0.5 inch (1.27cm), at least about 1 inch (2.54cm), at least about 1.5 inches (3.81cm) or at least about 2 inches (5.08cm). In an embodiment, the maximum length on any dimension is about 2 inches (5.08cm) to about 4 inches (10.16cm). In an embodiment, the liquid-containing nonwoven article has a shape selected from the group consisting of a quadrilateral, a triangle, a circle, a star, a heart, an octagon, a pentagon, a hexagon, a heptagon, an ellipse, a crescent, a semicircle, a cross, a trefoil, a quadrilobate, a teardrop, a pentagram, a hexagram, an octagon, a crown, a snowflake, a shield, a cloud, an arrow, and combinations thereof.

[0294] In general, the nonwoven article containing liquid can include fibers comprising any fiber-forming material disclosed herein. In an embodiment, the core nonwoven fabric comprises fibers comprising a first polyvinyl alcohol fiber-forming material selected from a polyvinyl alcohol homopolymer, a polyvinyl alcohol copolymer, and a combination of the foregoing. In an embodiment, the first polyvinyl alcohol comprises a polyvinyl alcohol copolymer comprising an anion-modified polyvinyl alcohol. In an embodiment, the anion-modified polyvinyl alcohol comprises (alkyl) acrylate-modified polyvinyl alcohol, maleate-modified polyvinyl alcohol, sulfonate-modified polyvinyl alcohol, or a combination thereof. In an embodiment, the first polyvinyl alcohol comprises a polyvinyl alcohol homopolymer.

[0295] In an embodiment, the outer nonwoven fabric comprises fibers comprising a second polyvinyl alcohol fiber-forming material selected from a polyvinyl alcohol homopolymer, a polyvinyl alcohol copolymer, and combinations of the foregoing. In an embodiment, the second polyvinyl alcohol comprises a polyvinyl alcohol copolymer comprising an anion-modified polyvinyl alcohol. In an embodiment, the anion-modified polyvinyl alcohol comprises an (alkyl) acrylate-modified polyvinyl alcohol, a maleate-modified polyvinyl alcohol, a sulfonate-modified polyvinyl alcohol, or a combination thereof. In an embodiment, the second polyvinyl alcohol comprises a polyvinyl alcohol homopolymer.

[0296] In an embodiment, the core nonwoven fabric comprises a first plurality of fibers comprising a first polyvinyl alcohol fiber-forming material, and the first plurality of fibers further comprises one or more fiber-forming materials selected from the group consisting of polyacrylates, polyvinyl pyrrolidone, polyethylene imine, guar gum, gum arabic, gum tannin, carrageenan, water-soluble starch, water-soluble cellulose, cellulose ether, cellulose ester, and cellulose amide. In an embodiment, the outer nonwoven fabric comprises a second plurality of fibers comprising a second polyvinyl alcohol fiber-forming material, and the second plurality of fibers further comprises one or more fiber-forming materials selected from the group consisting of polyacrylates, polyvinyl pyrrolidone, polyethylene imine, guar gum, gum arabic, gum tannin, carrageenan, water-soluble starch, water-soluble cellulose, cellulose ether, cellulose ester, and cellulose amide.

[0297] Generally speaking, the first polyvinyl alcohol of the core nonwoven fabric and the second polyvinyl alcohol of the outer nonwoven fabric can be the same or different. In embodiments where the first and second polyvinyl alcohols are different, the first polyvinyl alcohol fiber-forming material and the second polyvinyl alcohol fiber-forming material can have differences in viscosity, degree of hydrolysis, degree of copolymerization, type of copolymer modification, or a combination thereof.

[0298] Generally, the core nonwoven fabric prior to the addition of liquid can be the same or different from the outer nonwoven fabric. Advantageously, the liquid-containing nonwoven article can provide a consumer product containing a liquid composition that has a cloth-like feel that is comfortable to handle, in contrast to current commercially available pouches made of water-soluble polymeric films that have an unpleasant rubber or plastic-like feel when handled by consumers. The liquid-containing nonwoven article can have a softness rating of 1 to 5 as determined using the softness rating method disclosed herein.

[0299] The liquid-containing nonwoven article can be prepared by contacting a core nonwoven fabric with a liquid containing an active agent, enveloping the core nonwoven fabric with an outer nonwoven fabric, and sealing the outer nonwoven fabric to enclose the core nonwoven fabric.

[0300] In an embodiment, the method of making a liquid-containing nonwoven article further comprises folding the core nonwoven fabric upon itself 2 to 50 times, 3 to 45 times, 4 to 40 times, 5 to 35 times, or 6 to 30 times. Figure 6 and 7 As shown, the core nonwoven fabric is folded upon itself to provide a thicker nonwoven core. The method of folding is not particularly limited and may be an accordion style ( Figure 6 ) or continuous folding in the same direction ( Figure 7 ). After folding, the layers may optionally be bonded together using any bonding method known in the art.

[0301] In general, contacting the core nonwoven fabric with a liquid comprising an active agent can use any method known in the art for applying a liquid composition to a substrate. Methods for contacting include, but are not limited to, one or more of the following: gravure coating, dip coating, slot die coating, line coating, overflow coating, spraying, and immersing the core nonwoven fabric in a bath of a liquid comprising an active agent. In an embodiment, folding occurs after contacting, and contacting comprises one or more of gravure coating, dip coating, slot die coating, line coating, overflow coating, and spraying. In an embodiment, folding occurs before contacting, and contacting comprises immersing the core nonwoven fabric in a bath of a liquid comprising an active agent.

[0302] In an embodiment, the method further comprises preparing the outer nonwoven fabric by laminating, stacking, folding or laminating multiple layers of nonwoven fabrics.One or more nonwoven fabrics may be superimposed and optionally bonded and laminated together.

[0303] In general, any process that can comprise outer nonwoven fabric forms inner space and core nonwoven fabric is arranged in described inner space by outer nonwoven fabric encapsulation core nonwoven fabric.In an embodiment, outer nonwoven fabric encapsulation core nonwoven fabric comprises wrapping core nonwoven fabric with outer nonwoven fabric, inserting core nonwoven fabric into the encapsulation comprising outer nonwoven fabric, or inserting core nonwoven fabric into the sleeve comprising outer nonwoven fabric.In an embodiment, encapsulation comprises horizontal flow parcel.External nonwoven fabric can be sealed together to manufacture around the tube of the core nonwoven fabric containing the liquid comprising active agent along processing direction subsequently.

[0304] As shown in Figure 4, the outer nonwoven fabric can have a machine direction (301) and a transverse direction (300), and the core nonwoven fabric (302) can be encapsulated by wrapping the core nonwoven fabric with the outer nonwoven fabric. As shown in Figure 5, the seal can include sealing the outer nonwoven fabric (303) at two or more points along the machine direction. The seal can further include sealing the outer nonwoven fabric along at least one edge in the transverse edge (304). The seal can include any sealing method known in the art, such as heat sealing, solvent welding and adhesive sealing. Typically, only the area forming the sealed portion is treated with heat or solvent. Heat or solvent can be applied by any method. If solvent or wet sealing or welding is used, it may be preferred to also apply heat. Preferred wet or solvent sealing / welding methods include selectively applying solvents by, for example, spraying or printing solvents onto the area to be sealed, and then applying pressure to these areas to form a sealed portion. For example, sealing rollers and sealing tapes (optionally also providing heat) can be used. The solvent used for solvent sealing / welding can include any suitable solvent, such as a polar solvent including water and / or glycerol. Without wishing to be bound by theory, it is believed that solution sealing results in a less crystalline nonwoven fiber, which in turn helps to leave less residue after dissolving the nonwoven article containing the liquid.

[0305] Nonwoven articles containing liquids can be prepared in an in-line process. Figure 5B As shown, the method of preparing a nonwoven article containing a liquid may further include cutting the nonwoven article (305) in the cross-direction along the sealing portion (303) in the machine direction to provide a unit dose having a flange (307). A die-cutting system may be used to separate individual doses ( Figure 5B (306)). The cutouts are disposed between the unit dose sealing portions so that a flange is created around each unit dose. In embodiments, the flange may be at least 1 mm and not more than 10 mm, such as about 1.5 mm to about 9 mm, about 2 mm to about 7.5 mm, or about 2.5 mm to about 5 mm. The individual unit doses may then be collected, weighed, and divided for placement into secondary packaging.

[0306] Dissolution and disintegration test (MSTM 205)

[0307] According to MonoSol Test Method 205 (MSTM 205), a method known in the art, nonwoven fabrics, water-soluble films, or composite structures can be characterized or tested for dissolution time and disintegration time. See, e.g., U.S. Pat. No. 7,022,656. The description provided below refers to nonwoven fabrics, but it is equally applicable to water-soluble films or composite structures.

[0308] Equipment and Materials:

[0309] 600mL beaker

[0310] Magnetic stirrer (Labline model 1250 or equivalent)

[0311] Magnetic stirring bar (5cm)

[0312] Thermometer (0 to 100℃±1℃)

[0313] Template, stainless steel (3.8cm×3.2cm)

[0314] Timer (0-300 seconds, accurate to the nearest second)

[0315] Polaroid 35mm slider mount (or equivalent)

[0316] Monoso 35mm Slider Mount Standoff (or equivalent)

[0317] Distilled water

[0318] For each nonwoven fabric to be tested, three test specimens are cut from the nonwoven fabric sample as 3.8 cm x 3.2 cm specimens. The specimens should be cut from areas of the fabric that are evenly spaced in the cross-machine direction of the fabric. Each test specimen is then analyzed using the following procedure.

[0319] Each specimen was snapped into a separate 35 mm slide mount.

[0320] Fill the beaker with 500 mL of distilled water. Measure the water temperature with a thermometer and heat or cool the water as necessary to maintain the temperature at the temperature at which dissolution is determined, for example 20°C (about 68°F).

[0321] Mark the height of the water column. Place the electromagnetic stirrer on the base of the stand. Place the beaker on the electromagnetic stirrer, add the electromagnetic stir bar to the beaker, turn on the stirrer, and adjust the stirring speed until a vortex is created that is approximately one fifth the height of the water column. Mark the depth of the vortex.

[0322] Fasten the 35 mm slider mount into the alligator clamp of the 35 mm slider mount holder so that the long end of the slider mount is parallel to the surface of the water. The depth adjuster of the holder should be set so that when dropped, the end of the clamp will be 0.6 cm below the surface of the water. One of the short sides of the slider mount should be against the side of the beaker while the other is positioned just above the center of the stir bar so that the nonwoven surface is perpendicular to the water flow.

[0323] In one motion, the fastened slide and fixture are lowered into the water and a timer is started. Disintegration occurs when the nonwoven fabric breaks apart. When all visible nonwoven fabric is released from the slide mount, the slide is raised out of the water while continuing to monitor the solution for undissolved nonwoven fabric fragments. Dissolution occurs when all nonwoven fabric fragments are no longer visible and the solution becomes clear.

[0324] Results should include the following: complete sample identification; individual and average disintegration and dissolution times; and the water temperature of the test samples.

[0325] Method for determining the solubility of single fibers

[0326] The solubility of a single fiber can be characterized by the water break temperature. The fiber break temperature can be determined as follows. A load of 2 mg / dtex is placed on a fiber of fixed length 100 mm. The water temperature starts at 1.5°C and then increases in 1.5°C increments every 2 minutes until the fiber breaks. The temperature at which the fiber breaks is denoted as the water break temperature.

[0327] The solubility of a single fiber can also be characterized by the temperature of complete dissolution. The temperature of complete dissolution can be determined as follows. 0.2 g of a fiber of fixed length 2 mm is added to 100 mL of water. The water temperature starts at 1.5°C and then increases by 1.5°C increments every 2 minutes until the fiber is completely dissolved. The sample is stirred at each temperature. The temperature at which the fiber is completely dissolved is denoted as the complete dissolution temperature.

[0328] Diameter test method

[0329] The diameter of the fiber in the discrete fiber or nonwoven fabric is determined by using a scanning electron microscope (SEM) or an optical microscope and image analysis software. Select a magnification of 200 to 10,000 times so that the fiber is appropriately enlarged for measurement. When using SEM, the sample is sputtered with gold or palladium compounds to avoid charging and vibration of the fiber in the electron beam. A manual program for measuring fiber diameter is used from the image (on the monitor screen) taken with SEM or an optical microscope. Using the mouse and cursor tool, the edge of the randomly selected fiber is sought, and then the other edge of the fiber is measured across its width (that is, perpendicular to the fiber direction at the point). The image analysis tool that is scaled and calibrated provides scaling to obtain the actual reading in microns. For the fiber in the nonwoven fabric, a number of fibers are randomly selected in the sample of the nonwoven fabric using SEM or an optical microscope. At least two parts of the nonwoven fabric material are cut and tested in this way. At least 100 such measurements are carried out in total, and all data are recorded subsequently for statistical analysis. The recorded data are used to calculate the mean value (mean) of the fiber, the standard deviation of the fiber, and the median fiber diameter.

[0330] Tensile strength, modulus and elongation testing

[0331] The following analysis is performed by characterizing or testing the following nonwoven fabrics, water-soluble films or composite structures: tensile strength according to tensile strength (TS) test, modulus (or tensile stress) according to modulus (MOD) test and elongation according to elongation test. The description provided below refers to nonwoven fabrics, but it is also applicable to water-soluble films or composite structures. The procedure includes measuring tensile strength according to ASTM D 882 ("Standard Test Method for Tensile Properties of Thin Plastic Sheeting") or equivalent methods and measuring modulus at 10% elongation. The collection of nonwoven fabric data is performed using an INSTRON tensile testing device (5544 type tensile tester or equivalent). Each measurement is tested along the machine direction (MD) (if applicable) for at least three test samples, and each test sample is cut with a reliable cutting tool to ensure dimensional stability and reproducibility. Tests are carried out in a standard laboratory atmosphere at 23°C ± 2.0°C and 35% ± 5% relative humidity. For tensile strength or modulus determination, prepare 1 inch wide (2.54cm) nonwoven fabric sample.Sample is subsequently transferred to Instron tensile testing machine to proceed with testing, while minimizing exposure in 35% relative humidity environment.According to manufacturer's instructions, be ready to be equipped with 500N dynamometer and calibrated tensile testing machine.Assemble appropriate handle and face (Instron handle, with model 2702-032 face, it is coated with rubber and is 25mm wide, or equivalent).Sample is installed in tensile testing machine and analyzed to measure 100% modulus (that is, realize the stress required for 100% film elongation), tensile strength (that is, the stress required for fractured film) and elongation % (sample length during the fracture with respect to initial sample length).In general, the elongation % of sample is higher, and the processability feature of nonwoven fabric is better (for example, the formability of bag or bag increases).

[0332] Determination of basis weight

[0333] Basis weight is determined according to ASTM D3776 / D3776M-09a(2017). In simple terms, the cut area is at least 130 cm 2 or from different locations within the sample with a total area of ​​at least 130 cm 2 Weigh the samples on a top-loading analytical balance with a resolution of ±0.001 g to determine the mass. Use a draft shield to protect the balance from drafts and other disturbances. Fabric samples can be weighed together. Calculate mass in ounces per square yard, ounces per linear yard, linear yards per pound, or grams per square meter to three significant figures.

[0334] Determination of moisture vapor permeability

[0335] The moisture vapor transmission rate (MVTR) is determined according to MSTM-136. The MVTR defines how much moisture passes through a nonwoven fabric, film or composite sample per day. The description provided below refers to nonwoven fabrics, but it is equally applicable to water-soluble film or composite structures.

[0336] Equipment and Materials:

[0337] Permatran - Type W 3 / 34 (or equivalent)

[0338] Nitrogen compressed gas cylinders (99.7% or above)

[0339] Regulator - Tee (Part No. 027-343)

[0340] Mains supply regulator

[0341] HPLC grade water (or equivalent)

[0342] 10cc syringe with Luerlok tip (Part No. 800-020)

[0343] Powder-free gloves

[0344] High Vacuum Grease (Part No. 930-022)

[0345] (2) Test unit

[0346] Cutting Template

[0347] Cutting Board

[0348] Razor blade with handle

[0349] Cut resistant gloves

[0350] Preparation of the Permaturan W-3 / 34: Make sure the nitrogen pressure level is above 300psi, the pressure on the carrier gas regulator-tee reads 29psi (not to exceed 32psi) and the main line supply regulator pressure is set to 35psi. Open the door on the dashboard to access the humidifier to check the water level. If the water level is low, fill the syringe with HPLC grade water and insert the Luer fitting on the syringe into the "Fill Port" of the reservoir. Open the "Fill Valve" by turning it 2-3 turns counterclockwise, then push in the plunger on the syringe to force water into the reservoir. Close the "Fill Valve" and remove the syringe. Note: Do not allow the water level to exceed the line marked adjacent to the reservoir.

[0351] Preparation and testing samples: For each nonwoven fabric to be tested, take the sample fabric and lay it flat on the cutting board. Place the template on top of the fabric and cut the sample with a razor blade with a handle. Make sure to wear cut-resistant gloves when cutting the sample. Set the sample aside. Grease the sealing surface of the test unit top piece with high vacuum grease. Mount the nonwoven fabric sample to the top of the test unit top piece. Note: Orientation may be important. If it is a homogeneous material, then the orientation is not critical. If it is a multi-layer and laminated material, then place the multi-layer film or laminate with the barrier coating or laminate facing up, toward the top of the unit. For example, a single-sided wax-coated PVOH fabric should be mounted with the wax side facing up, placing the wax toward the carrier gas (nitrogen). Place the test unit top piece on top of the test unit bottom piece. Make sure the test unit is clamped together with a good seal. Press the unit load / unload button to open the unit tray. Grasp the front and back edges of the test unit and lower it straight down. Close the unit tray completely by gently pushing straight toward the plate. Press the cell load / unload button to clamp the cell. NOTE: You should hear a click. Repeat for the second sample.

[0352] After the sample is loaded and the instrument is ready, the test parameters must be set. NOTE: There are two types of test parameters, Unit Parameters and Instrument Parameters. Unit Parameters are specific to each unit, while Instrument Parameters are common to all units. Touch the "Test Button" on the screen. Under "Automatic Test" select "Tab A". Touch the "Unit Tab". Fill in the following by touching each bubble: ID, Area (cm'2), Thickness (mils). NOTE: The area of ​​the template is 50cm 2 . Repeat for "Tab B". Touch the "Instrument Tab". Fill in the following by touching each bubble: Cell Temperature (°C) and Test Gas RH (%). NOTE: Make sure 100% RH is set to OFF. Cell Temperature can be set from a minimum of 10°C to a maximum of 40°C. Test Gas RH can be set from a minimum of 5% to 90%. If 100% RH is desired, a different approach is required. Repeat for "Tab B". Once the test parameters are set, select "Start Selected" or "Start All", depending on the number of samples. NOTE: The indicator light for each cell on the front panel will be green, indicating the start of the test.

[0353] Surface resistivity measurement

[0354] The surface resistivity of nonwoven fabrics and films can be measured according to ASTM D257.

[0355] Softness level

[0356] The hand feel of the nonwoven fabric, liquid-containing nonwoven article or nonwoven composite material article of the present disclosure is related to the softness of the sample and can be evaluated using a relative test method. The tester performing the softness evaluation uses clean hands to feel the sample in any manner or method of personal choice to determine the softness rating of the nonwoven fabric and article of the present disclosure compared to the following: a control material of a nonwoven fabric composed of fibers composed of a polyvinyl alcohol homopolymer with a degree of hydrolysis of 88%, the fibers having a cut of 2.2 dtex / 51 mm, and a softness rating of 1 (softest); and a control material of a nonwoven fabric composed of fibers, the fibers consisting of 75% polyvinyl alcohol homopolymer with a degree of hydrolysis of 88% (the fibers having a cut of 2.2 / 51 mm) and 25% 22 dtex / 38 mm PET fibers, and a softness rating of 5 (roughest / coarsest). The hand panel can be conducted in a blind study so that the assessors are not influenced by their perception of the sample name. The sample can be rated from 1 to 5.

[0357] Horizontal Wicking Test

[0358] The horizontal wicking of nonwoven fabrics is tested as disclosed herein. The test is completed with the blower turned off in a fume hood. The liquid to be tested is exposed to the atmosphere for a time suitable for equilibrating the liquid to room conditions. The nonwoven strips are cut so that the processing direction is parallel to the direction of liquid movement. A glass petri dish is used as a reservoir and filled with liquid to the highest possible water level to test wicking. The lid of the petri dish is placed adjacent to the petri dish to support the nonwoven fabric. A binder clip is set on the petri dish lid to support the end of the nonwoven strip so that it will not adhere to the glass. Figure 8 The sample setup is shown in . A video of the liquid passing through the nonwoven is taken and a ruler can be seen. The distance traveled by the liquid in mm is recorded at different time points. The distance is plotted over time to obtain the wicking rate. Horizontal wicking occurs in three phases, the wetting delay, the Waschbone phase (linear flux of solution through the substrate) and the decline phase. The data used for the Waschbone slope, wicking rate and absorption rate are from when the test was run for 30 seconds, which is well within the Waschbone phase. The rate v 芯吸 Determined according to the following equation:

[0359] Lucas-Washburn Equation:

[0360]

[0361] Absorption capacity and rate

[0362] The absorption capacity and rate of nonwoven fabrics were tested as disclosed herein. For liquid absorption capacity (LAC%), the test samples were immersed (one at a time) in a 20 mm deep test liquid for 60 seconds. The test samples were vertically drained for 120 seconds. The LAC% was then calculated according to the following equation:

[0363] Absorption rate (volume rate wicking per unit area) The wicking rate v will be obtained from the horizontal wicking test 芯吸 Multiply by the void fraction φ of the nonwoven fabric sample to calculate:

[0364]

[0365] The void fraction can be determined by dipping a dry, weighed nonwoven sample into a disk with a known volume of water. The nonwoven is soaked for 15 seconds and drained on a Petri dish for 30 seconds. The amount of water (volume) lost from the Petri dish is measured and the void fraction is calculated according to the following equation:

[0366] Examples

[0367] The nonwoven fabric of the examples is made from one or more fibers selected from the group consisting of fibers D, fibers E, fibers F, and fibers G, which are described below.

[0368] Fiber D is a commercially available PVOH staple fiber product comprising a PVOH homopolymer having a degree of hydrolysis (DH) of 88% and a fineness of 1.7-2.2 dtex. Fiber D will dissolve in water at a temperature of 20°C under the following conditions: 10 g of the fiber is placed in a 500 cc container, followed by 30 times the weight of the fiber sample in distilled water. The water is gently stirred, and the sample is observed to be completely dissolved after a few minutes, typically within 15 minutes.

[0369] Fiber E is a commercially available PVOH staple fiber product comprising a PVOH homopolymer having a degree of hydrolysis (DH) of 96% and a denier of 1.4-2.2. Fiber E will dissolve in water at a temperature of 40°C under the following conditions: 10 g of the fiber is placed in a 500 cc container, followed by 30 times the weight of the fiber sample in distilled water. The water is gently stirred, and the sample is observed to be completely dissolved after a few minutes, typically within 15 minutes.

[0370] Fiber F is a commercially available PVOH staple fiber product comprising a PVOH homopolymer having a degree of hydrolysis (DH) of 98% and a denier of 1.4-2.2. Fiber F will dissolve in water at a temperature of 70°C under the following conditions: 10 g of the fiber is placed in a 500 cc container, followed by 30 times the weight of the fiber sample in distilled water. The water is gently stirred, and the sample is observed to be completely dissolved after a few minutes, typically within 15 minutes.

[0371] Fiber G is a commercially available PVOH staple fiber product comprising a PVOH homopolymer having a degree of hydrolysis (DH) of 99+% and a fineness of 1.7 dtex. Fiber G will dissolve in water at a temperature of 95°C under the following conditions: 10 g of fiber is placed in a 500 cc container, followed by 30 times the weight of the fiber sample in distilled water. The water is gently stirred, and the sample is observed to be completely dissolved after a few minutes, typically within 15 minutes.

[0372] Example 1

[0373] Various nonwoven fabrics are prepared using fibers comprising a single PVOH fiber forming material. The fiber is composed of a PVOH homopolymer with different degrees of hydrolysis. Specifically, DH is 88%, 96%, 98% and 99% of fiber D, fiber E, fiber F and fiber G, which are used alone or 50 / 50 (by weight) to provide a nonwoven fabric, and its average DH is 88% (D fiber), 92% (D / E fiber), 93% (D / F fiber), 93.5% (D / G fiber), 96% (E fiber), 97% (E / F fiber), 97.5% (E / G fiber), 98% (F fiber), 98.5% (F / G fiber) and 99+% (G fiber). The fiber calender is bonded to form a nonwoven fabric. The nonwoven fabric with an average DH of 88% is calendered at a speed of 40psi, 2FPM (feet / minute) and a temperature of 140°C. If necessary and depending on the DH of the fibers, the remaining nonwoven fabrics were calendered at 40 psi and temperatures between 140° C. and 190° C. at a rate of 1-2 FPM to achieve the same degree of bonding as the nonwoven fabric with an average DH of 88%. The degree of bonding of the two nonwoven fabrics is considered to be the same when the tensile strength of the fabrics is the same (±5%) as measured according to the tensile strength test disclosed herein. The resulting nonwoven fabrics were tested for horizontal wicking and absorption capacity and rate according to the methods provided herein.

[0374] The liquids tested with the various nonwoven fabrics were DI water, hexane, synthetic blood, and synthetic urine. Synthetic blood is a 94% water mixture of hemoglobin, amino acids, proteins, and other harmless components. Synthetic urine is a 97% water mixture of urea, magnesium sulfate heptahydrate, calcium chloride dehydrate, and sodium chloride.

[0375] As shown in FIG. 9 , for water and synthetic urine, as the average DH of the nonwoven fabric increases, the Wassbon slope, wicking rate, and absorption rate increase; for synthetic blood, as the average DH increases, the Wassbon slope and wicking rate increase and the absorption rate is maintained; and for hexane, as the DH of the nonwoven fabric increases, each of the Wassbon slope, wicking rate, and absorption rate decreases.

[0376] like Fig.10 As shown, for liquid absorbent capacity, high DH fibers have a greater impact on capacity than low DH fibers when provided in a blend, rather than exhibiting a blend regular effect on absorbent capacity. A nonwoven fabric containing only cotton ball material was also tested for comparison.

[0377] Example 2

[0378] Various multi-layer nonwoven fabrics are prepared using nonwoven fabrics including fibers containing a single PVOH fiber forming material. The fibers are composed of PVOH homopolymers with different degrees of hydrolysis. Specifically, fiber D, fiber E, fiber F, and fiber G with DH of 88%, 96%, 98%, and 99+% are used alone or in a blend. The fibers of the first layer are combed and the fibers of the second layer are stacked on top of the fibers of the first layer. The two layers are simultaneously calendered to form nonwoven fabrics and multi-layer nonwoven articles. The nonwoven fabric with an average DH of 88% is calendered at 40psi, 2FPM, and a temperature of 140°C. As needed and depending on the DH of the fiber, the remaining nonwoven fabrics are calendered at 1-2FPM at 40psi and a temperature between 140°C and 190°C to achieve the same degree of bonding as the nonwoven fabric with an average DH of 88%. When the tensile strength of the fabric is the same (±5%) as measured according to the tensile strength test disclosed herein, the bonding degree of the two nonwoven fabrics is considered to be the same. Articles were prepared by combining two nonwoven fabrics having the same composition and basic weight, and their average DH were 92% (50 / 50 D / E fiber nonwoven fabric), 93% (50 / 50 D / F fiber nonwoven fabric), 93.5% (50 / 50 D / G fiber nonwoven fabric), 94% (25 / 75 D / E fiber nonwoven fabric), 95.2% (10 / 90 D / E fiber nonwoven fabric), 96% (E fiber nonwoven fabric), 97% (50 / 50 E / F fiber nonwoven fabric) and 97.5% (50 / 50 E / G fiber nonwoven fabric).

[0379] All multi-layer articles were tested for Horizontal Wicking and Absorbent Capacity and Rate according to the methods provided herein.

[0380] The liquids tested with the various nonwoven fabrics were DI water, hexane, synthetic blood, and synthetic urine. Synthetic blood is a 94% water mixture of hemoglobin, amino acids, proteins, and other harmless components. Synthetic urine is a 97% water mixture of urea, magnesium sulfate heptahydrate, calcium chloride dehydrate, and sodium chloride.

[0381] As shown in Figure 11, for all liquids except hexane, the Washburn slope, wicking rate, and absorption rate increased as the average DH of the multilayer article increased. For hexane, the Washburn slope, wicking rate, and absorption rate remained relatively stable with a slight increase as the DH of the multilayer article increased.

[0382] like Fig.12 As shown, for liquid absorption capacity, the high DH layer has a greater impact on capacity than the low DH fibers when provided in a blend, rather than exhibiting a mixed regular effect on absorption capacity. A nonwoven fabric containing only cotton ball material was also tested for comparison.

[0383] Example 3

[0384] Various multilayer nonwoven fabrics were prepared using nonwoven fabrics with fibers containing a single PVOH fiber forming material. The fibers were composed of PVOH homopolymers with different degrees of hydrolysis. Specifically, fiber D, fiber E, fiber F, and fiber G with DH of 88%, 96%, 98%, and 99+% were used alone. The fibers of the first layer were combed and the fibers of the second layer were stacked on top of the fibers of the first layer. The two layers were simultaneously calendered to form nonwoven fabrics and multilayer nonwoven articles. The nonwoven fabric was calendered at 40psi, 2FPM, and a temperature of 150°C. Some single-layer articles were also prepared using air-guided bonding. Air-guided bonding was performed at a speed of 6:50 at 180°C. The air-guided bonded nonwoven fabric included PVOH fibers with a DH of 96% and up to 5% by weight of polyethylene terephthalate (PET) fibers to help bonding. For multilayer articles, DH was considered to be the average DH of the two layers. Articles were prepared by combining two nonwoven fabrics having different compositions but the same basic weight, and their average DH were 92% (D fiber nonwoven fabric / E fiber nonwoven fabric), 93% (D fiber nonwoven fabric / F fiber nonwoven fabric), 93.5% (D fiber nonwoven fabric / G fiber nonwoven fabric), 97% (E fiber nonwoven fabric / F fiber nonwoven fabric) and 97.5% (E fiber nonwoven fabric / G fiber nonwoven fabric).

[0385] The horizontal wicking and absorption capacity and rate of a multilayer article comprising two different nonwoven fabrics were tested according to the method provided herein. Multiple tests were run with the multilayer article in a first orientation with the higher DH layer facing upward and a second orientation with the lower DH layer facing upward. No discernible difference in wicking rate was found between the two orientations.

[0386] The liquids tested with the various nonwoven fabrics were DI water, hexane, synthetic blood, and synthetic urine. Synthetic blood is a 94% water mixture of hemoglobin, amino acids, proteins, and other harmless components. Synthetic urine is a 97% water mixture of urea, magnesium sulfate heptahydrate, calcium chloride dehydrate, and sodium chloride.

[0387] The articles exhibited the same trend as in Example 1, with the Washburn slope increasing with increasing average DH.

[0388] As shown in Figure 13, for all liquids except hexane, the Washburn slope, wicking rate, and absorption rate increased as the average DH of the multilayer article increased. For hexane, the Washburn slope, wicking rate, and absorption rate remained relatively constant, increasing slightly as the DH of the multilayer article increased. The data in Figure 13 were collected for a calender bonded article, where the nonwoven fabric was oriented with the higher DH side facing up and the lower DH side exposed to the liquid.

[0389] like Fig.14 As shown, the performance of nonwoven fabrics depends on the average DH of the article and the bonding type. Air-distribution bonded nonwoven fabrics exhibit higher LAC% values ​​relative to their calender-bonded counterparts. This trend indicates that with a higher degree of bonding, such as calender bonding (which has higher temperatures, pressures, and longer residence times than air-distribution processes), the LAC of the article decreases. Fig.14 The labels on the x-axis of refer to the following nonwoven fabrics of the present disclosure: "E blend" is a single-layer nonwoven fabric composed of E fibers (from Example 1), "E blend, 1.75% PET" is a single-layer nonwoven fabric including E fibers and 1.75 wt.% PET fibers, "E blend, 2.5% PET" is a single-layer nonwoven fabric including E fibers and 2.5 wt.% PET fibers, "E blend, 5% PET" is a single-layer nonwoven fabric including E fibers and 5 wt.% PET fibers, "E multilayer" is a double-layer nonwoven fabric in which each layer is composed of E fibers (from Example 2), "E / F blend" is a double-layer nonwoven article in which one layer is composed of E fibers and one layer is composed of F fibers, and "E / G blend" is a double-layer nonwoven article in which one layer is composed of E fibers and one layer is composed of G fibers. Nonwoven fabrics containing only cotton ball material were also tested for comparison.

[0390] Example 4

[0391] The single-layer nonwoven fabric is prepared from a mixture of polyvinyl alcohol fibers (fiber E) and polylactic acid (PLA) fibers or cotton fibers. In the nonwoven fabric, the polyvinyl alcohol fibers account for 50 wt.% of the total fiber weight and the other 50 wt.% are PLA fibers or cotton fibers. The polyvinyl alcohol fibers are carded together with the PLA fibers or cotton fibers and calendered at 40 psi and 140° C. The basis weight of the resulting nonwoven fabric is about 50 gsm.

[0392] Thus, Example 4 demonstrates the preparation of a heterogeneous nonwoven fabric comprising water-soluble fibers and water-insoluble fibers.

[0393] The foregoing description has been given solely for clearness of understanding, and no unnecessary limitations are to be understood therefrom, as modifications within the scope of the disclosure may be obvious to one skilled in the art.

[0394] All patents, publications, and references cited herein are incorporated herein by reference. In the event of a conflict between the present disclosure and the incorporated patents, publications, and references, the present disclosure shall control.

Claims

1. A wearable absorbent article comprising: an absorbent core having a wearer-facing side and an outward-facing side; and Liquid collection layer, The liquid acquisition layer comprises a nonwoven fabric comprising a plurality of fibers containing a water-soluble polyvinyl alcohol fiber-forming material.

2. The absorbent article of claim 1, wherein the acquisition layer is disposed on the wearer-facing side of the absorbent core.

3. The absorbent article of claim 1, wherein the acquisition layer is disposed on the outwardly facing side of the absorbent core.

4. The absorbent article of claim 1 , wherein the acquisition layer is wrapped around at least a portion of the absorbent core.

5. The absorbent article of claim 1, wherein the acquisition layer is in contact with the absorbent core.

6. The absorbent article of claim 1, further comprising an intermediate layer disposed between the acquisition layer and the absorbent core.

7. An absorbent article according to claim 1, wherein the liquid collection layer is in contact with the absorbent core on the side of the absorbent core facing outward and an intermediate layer is arranged between the acquisition layer and the absorbent core, on the side of the absorbent core facing the wearer.

8. The absorbent article of claim 1 , wherein the acquisition layer comprises: Nonwoven composite material comprising a first layer comprising a first nonwoven fabric comprising a first plurality of fibers; a second layer comprising a second nonwoven fabric comprising a second plurality of fibers; and Optionally, a third layer comprising a third nonwoven fabric comprising a third plurality of fibers; One or more layers among the first layer, the second layer and the third layer contain the water-soluble polyvinyl alcohol fiber-forming material.

9. The absorbent article of claim 1, wherein the acquisition layer comprises the nonwoven composite article of claim 1.

10. A liquid-containing nonwoven article comprising: a core nonwoven fabric comprising a first plurality of fibers comprising a first polyvinyl alcohol fiber-forming material, wherein the core nonwoven fabric comprises a liquid comprising an active agent; and An outer nonwoven fabric comprises a second plurality of fibers comprising a second polyvinyl alcohol fiber-forming material, wherein the core nonwoven fabric is enclosed by the outer nonwoven fabric.

11. The liquid-containing nonwoven article of claim 10, wherein the outer nonwoven fabric is wrapped around the core nonwoven fabric.

12. The liquid-containing nonwoven article of claim 10, wherein the outer nonwoven fabric has the form of a sleeve or an envelope and the core nonwoven fabric is provided in the sleeve or the envelope.

13. The liquid-containing nonwoven article of claim 10, wherein the core nonwoven web has a first length in a first direction and the outer nonwoven web has a second length in a first dimension that is equal to the first length.

14. The liquid-containing nonwoven article of claim 10, wherein the core nonwoven fabric is saturated with the liquid.

15. The liquid-containing nonwoven article of claim 10, wherein the weight of the core nonwoven fabric containing the liquid is two to ten times the weight of the core nonwoven fabric before the addition of the liquid containing the active agent.

16. The liquid-containing nonwoven article of claim 10, wherein the core nonwoven fabric comprises from about 5 grams (g) to about 30 g of liquid.

17. The liquid-containing nonwoven article of claim 10, wherein the core nonwoven fabric containing the liquid has a basis weight of about 30 gsm to about 2000 gsm.

18. The liquid-containing nonwoven article of claim 10, wherein the core nonwoven fabric has a dry basis weight of about 15 gsm to about 200 gsm.

19. The liquid-containing nonwoven article of claim 10, wherein the outer nonwoven web has a basis weight of about 15 gsm to about 400 gsm.

20. The liquid-containing nonwoven article of claim 10, wherein the outer nonwoven fabric has a thickness of about 0.5 millimeters (mm) to about 6.0 mm.

21. The liquid-containing nonwoven article of claim 10, wherein the core nonwoven is a single layer or comprises multiple nonwoven layers.

22. The liquid-containing nonwoven article of claim 10, wherein at least a portion of the core nonwoven fabric is in contact with at least a portion of the outer nonwoven fabric.

23. The liquid-containing nonwoven article of claim 10, wherein the liquid-containing nonwoven article has a plurality of edges and the core nonwoven fabric is sealed to the outer nonwoven fabric on at least two of the plurality of edges.

24. The liquid-containing nonwoven article of claim 10, further comprising at least one of a plurality of indicia or patterns on the outer nonwoven fabric.

25. The liquid-containing nonwoven article of claim 10, wherein the nonwoven article has a shape selected from the group consisting of a quadrilateral, a triangle, a circle, a star, a heart, an octagon, a pentagon, a hexagon, a heptagon, an oval, a crescent, a semicircle, a cross, a trefoil, a quadrilobal, a teardrop, a pentagram, a hexagram, an octagon, a crown, a snowflake, a shield, a cloud, an arrowhead, and combinations thereof.

26. The liquid-containing nonwoven article of claim 10, wherein the liquid-containing nonwoven article has a thickness of about 2 mm to about 50 mm.

27. The liquid-containing nonwoven article of claim 10, wherein the maximum length in one dimension is about 7 inches (17.78 cm).

28. The liquid-containing nonwoven article of claim 10, wherein the maximum length in one dimension is at least about 0.5 inches (1.27 cm).

29. The liquid-containing nonwoven article of claim 10, wherein the first polyvinyl alcohol fiber-forming material and the second polyvinyl alcohol fiber-forming material are each independently selected from the group consisting of polyvinyl alcohol homopolymers, polyvinyl alcohol copolymers, and combinations thereof.

30. The liquid-containing nonwoven article of claim 29, wherein the polyvinyl alcohol copolymer comprises anionically modified polyvinyl alcohol.

31. The liquid-containing nonwoven article of claim 30, wherein the anionically modified polyvinyl alcohol comprises (alkyl)acrylate-modified polyvinyl alcohol, maleate-modified polyvinyl alcohol, sulfonate-modified polyvinyl alcohol, or a combination thereof.

32. The liquid-containing nonwoven article of claim 10, wherein the first plurality of fibers or the second plurality of fibers further comprises one or more fiber-forming materials selected from the group consisting of polyacrylates, polyvinyl pyrrolidone, polyethylene imine, guar gum, gum arabic, gum tannin, carrageenan, water-soluble starch, water-soluble cellulose, cellulose ethers, cellulose esters, and cellulose amides.

33. The liquid-containing nonwoven article of claim 10, wherein the first polyvinyl alcohol fiber-forming material comprises a polyvinyl alcohol homopolymer.

34. The liquid-containing nonwoven article of claim 10, wherein the second polyvinyl alcohol fiber-forming material comprises a polyvinyl alcohol homopolymer.

35. The liquid-containing nonwoven article of claim 10, wherein the first polyvinyl alcohol fiber-forming material and the second polyvinyl alcohol fiber-forming material are the same.

36. The liquid-containing nonwoven article of claim 10, wherein the first polyvinyl alcohol fiber-forming material and the second polyvinyl alcohol fiber-forming material differ in viscosity, degree of hydrolysis, degree of copolymerization, or a combination thereof.

37. The liquid-containing nonwoven article of claim 10, wherein the active agent comprises one or more selected from the group consisting of enzymes, oils, fragrances, colorants, odor absorbers, aromatics, pesticides, fertilizers, oxidants, activating factors, acid catalysts, metal catalysts, ion scavengers, detergents, disinfectants, surfactants, bleaching agents, bleaching components, and fabric softeners.

38. A method of making a liquid-containing nonwoven article, the method comprising: forming a core nonwoven fabric comprising a first plurality of fibers comprising a first polyvinyl alcohol fiber-forming material; contacting the core nonwoven fabric with a liquid comprising an active agent; enveloping the core nonwoven fabric with an outer nonwoven fabric comprising a second plurality of fibers comprising a second polyvinyl alcohol fiber-forming material; as well as The outer nonwoven fabric is sealed to enclose the core nonwoven fabric.

39. The method of claim 38, further comprising folding the core nonwoven fabric upon itself 2 to 50 times.

40. The method of claim 38, wherein contacting the core nonwoven fabric with a liquid comprises gravure coating the core nonwoven fabric with the liquid, dip coating the core nonwoven fabric with the liquid, slot die coating the core nonwoven fabric with the liquid, line coating the core nonwoven fabric with the liquid, flood coating the core nonwoven fabric with the liquid, spray coating the core nonwoven fabric with the liquid, immersing the core nonwoven fabric in a bath of the liquid comprising the active agent, or a combination thereof.

41. The method of claim 40, wherein folding the core nonwoven fabric is performed after contacting the core nonwoven fabric with a liquid and the contacting comprises gravure coating the core nonwoven fabric with the liquid, dip coating the core nonwoven fabric with the liquid, slot die coating the core nonwoven fabric with the liquid, line coating the core nonwoven fabric with the liquid, flood coating the core nonwoven fabric with the liquid, spray coating the core nonwoven fabric with the liquid, or a combination thereof.

42. The method of claim 40, wherein folding the core nonwoven fabric is performed prior to immersing the core nonwoven fabric in the bath of the liquid containing the active agent.

43. The method of claim 38, further comprising preparing the outer nonwoven fabric by laminating, stacking, folding, or stacking multiple layers of one or more nonwoven fabrics.

44. The method of claim 38, wherein encapsulating the core nonwoven fabric with the outer nonwoven fabric comprises wrapping the core nonwoven fabric with the outer nonwoven fabric, inserting the core nonwoven fabric into an envelope containing the outer nonwoven fabric, or inserting the core nonwoven fabric into a sleeve containing the outer nonwoven fabric.

45. The method of claim 38, wherein the outer nonwoven web comprises a machine direction and a transverse direction perpendicular to the machine direction and sealing the outer nonwoven web comprises sealing the outer nonwoven web at two or more points along the machine direction.

46. ​​The method of claim 45, wherein sealing the outer nonwoven textile further comprises sealing at least one edge of the outer nonwoven textile along the cross direction.

47. The method of claim 38, wherein sealing the outer nonwoven web comprises heat sealing or solvent welding the outer nonwoven web.

48. The method of claim 47, wherein solvent welding the outer nonwoven fabric comprises solvent welding the outer nonwoven fabric using a polar solvent solution.

49. The method of claim 38, wherein the liquid-containing nonwoven article is produced by an in-line process.

50. The method of claim 45, further comprising cutting the nonwoven article in the cross direction along the seal portion in the machine direction to provide a unit dose comprising a flange.

51. The method of claim 50, wherein the flange is at least 1 mm and no greater than 10 mm.

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