Water-soluble nonwoven webs for packaging irritating chemicals

Abstract

Disclosed herein is a unit dose article comprising a packet having an outer wall comprising a nonwoven web comprising a sulfonate-modified PVOH fiber-forming material and / or a blend of fiber-forming materials comprising polyvinylpyrrolidone and sulfonate-modified PVOH, carboxyl-modified PVOH, or both. Disclosed herein is also a unit dose article comprising a composition comprising an irritating chemical. The present disclosure generally relates to water-soluble nonwoven webs and related compositions. More particularly, the present disclosure relates to a water-soluble nonwoven web for packaging an irritating chemical composition.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application No. 62 / 908,582, filed September 30, 2019, which is incorporated by reference in its entirety.

[0002] FIELD OF THEINVENTION The present disclosure relates generally to water soluble nonwoven webs and related compositions. More particularly, the present disclosure relates to water soluble nonwoven webs for packaging irritating chemical compositions. [Background technology]

[0003] background Water-soluble packaging materials are commonly used to simplify the dispersion, injection, dissolution, and metering of materials to be delivered. Traditional packaging materials include water-soluble films, and pouches made from them are commonly used to package compositions such as laundry, dishwashing detergent, or harsh chemicals. Consumers can add the composition in the pouch directly to water. Advantageously, this provides accurate metering while eliminating the need for consumers to measure the composition. Traditional water-soluble films may interact with pouch components (e.g. harsh chemicals) or moisture in the environment, which may affect the properties of the film, for example, when stored in contact with such chemicals, the solubility of the film may decrease over time, leaving undesirable residues after metering, and / or the mechanical properties of the film may deteriorate over time. In another type of problem, water-soluble films may discolor when stored in contact with harsh chemicals. In another type of problem, water-soluble films prepared from water-soluble polymers may stick to processing equipment and / or other water-soluble films. Such problems may occur especially when the film is formed into a pouch and the pouch is stored together in a secondary package.In addition, some pouches made from water-soluble polymeric films currently on the market have an unpleasant rubbery or plastic feel when handled by consumers.In another type of problem, when the water-soluble pouch is provided in, for example, bulk water, the water-soluble pouch may release the contents in a way that results in localized concentrations of the contents, rather than a more uniform distribution of the contents throughout the bulk solution.

[0004] Thus, there is a need in the art for a water-soluble packaging that is comfortable to handle, releases the pouch contents quickly to provide a more uniform distribution, has a reduced tendency to stick to other water-soluble packaging, yet remains water-soluble after storage in contact with the pouch contents. Summary of the Invention [Means for solving the problem]

[0005] overview One aspect of the disclosure provides a unit dose article comprising: a packet including an outer wall, the outer wall having an exterior surface and an interior surface defining an interior pouch volume, the outer wall comprising a nonwoven web comprising a plurality of fibers comprising a sulfonate-modified PVOH fiber-forming material comprising sulfonate-modified PVOH fiber-forming material comprising sulfonated anionic monomer units, the sulfonate-modified PVOH fiber-forming material having a degree of hydrolysis of at least 95%, and the sulfonated anionic monomer present in an amount in the range of about 1 mol % to about 5 mol %, and a composition contained in the interior pouch volume.

[0006] Another aspect of the present disclosure provides a unit dose article comprising: a packet including an outer wall, the outer wall having an exterior surface and an interior surface defining an inner pouch volume, the outer wall comprising a nonwoven web comprising a plurality of fibers comprising a blend of fiber-forming materials including (i) polyvinylpyrrolidone, and (ii) sulfonate-modified polyvinyl alcohol (PVOH), carboxyl-modified PVOH, or both; and a composition contained in the inner pouch volume.

[0007] Another aspect of the present disclosure provides a unit dose article of the present disclosure, wherein a pool and / or water treatment composition is contained in the inner pouch volume, the pool and / or water treatment composition comprises an oxidizer, a concentration of the oxidizer in the pool and / or water treatment composition ranges from 50% to 100% by weight, the oxidizer comprises calcium hypochlorite, and the packet optionally comprises a first coating comprising an acid scavenger provided on at least a portion of an inner surface of the outer wall.

[0008] Another aspect of the present disclosure provides a unit dose article of the present disclosure, wherein a pool and / or water treatment composition is contained in the inner pouch volume, the pool and / or water treatment composition comprises an oxidizer, a concentration of the oxidizer in the pool and / or water treatment composition ranges from 50% to 100% by weight, the oxidizer comprises trichloroisocyanuric acid, and the packet optionally comprises a first coating comprising an acid scavenger provided on at least a portion of an inner surface of the outer wall.

[0009] Another aspect of the present disclosure provides a process for metering a composition into bulk water, the process comprising contacting the bulk water with a unit dose article according to the present disclosure.

[0010] It is contemplated that for the compositions described herein, the desired features, including but not limited to components and compositional ranges thereof, fiber forming materials, multi-layer construction, fiber geometry, and / or mechanical properties, are selected from the various aspects and embodiments provided herein.

[0011] Further aspects and advantages will be apparent to those skilled in the art from a consideration of the following detailed description: While the fibers, nonwoven webs, unit dose articles, and compositions of the present disclosure are capable of embodiment in a variety of forms, the following description includes specific embodiments, with the understanding that the disclosure is for illustrative purposes and is not intended to limit the disclosure to the specific embodiments described herein. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Detailed Description In the disclosure provided herein, one aspect provides a unit dose article comprising a packet including an outer wall, the outer wall having an exterior surface and an interior surface defining an interior pouch volume, the outer wall comprising a nonwoven web, and a composition contained in the interior pouch volume. In an embodiment, the nonwoven web comprises a plurality of fibers comprising a sulfonate-modified polyvinyl alcohol ("PVOH") fiber-forming material comprising sulfonated anionic monomer units. In an embodiment, the sulfonate-modified PVOH fiber-forming material has a degree of hydrolysis of at least 95%. In an embodiment, the sulfonated anionic monomer is present in an amount ranging from about 1 mol% to about 5 mol%.

[0013] Another aspect of the present disclosure provides a unit dose article comprising a packet including an outer wall, the outer wall having an exterior surface and an interior surface defining an interior pouch volume, the outer wall comprising a nonwoven web, and a composition contained in the interior pouch volume. In an embodiment, the nonwoven web comprises a plurality of fibers comprising a blend of fiber-forming materials. In an embodiment, the blend of fiber-forming materials comprises (i) polyvinylpyrrolidone, and (ii) sulfonate-modified PVOH, carboxyl-modified PVOH, or both.

[0014] In the disclosure provided herein, one aspect provides a water-soluble nonwoven web comprising a plurality of fibers. In an embodiment, the plurality of fibers can comprise a blend of fiber-forming materials comprising carboxyl-modified polyvinyl alcohol, and sulfonate-modified polyvinyl alcohol, polyvinylpyrrolidone, or both, where the weight ratio of the carboxyl-modified polyvinyl alcohol fiber-forming material to the sulfonate and / or polyvinylpyrrolidone fiber-forming material is from about 3:1 to about 19:1. In an embodiment, the plurality of fibers can comprise a blend of fibers comprising fibers having a carboxyl-modified polyvinyl alcohol fiber-forming material and fibers having a sulfonate-modified polyvinyl alcohol fiber-forming material, fibers having a polyvinylpyrrolidone fiber-forming material, or both types of fibers, where the weight ratio of the carboxyl-modified polyvinyl alcohol fiber-forming material to the sulfonate and / or polyvinylpyrrolidone fiber-forming material is from about 3:1 to about 19:1. In an embodiment, the plurality of fibers can include a blend of fibers including a first fiber comprising a carboxyl-modified polyvinyl alcohol fiber-forming material, a sulfonate-modified polyvinyl alcohol fiber-forming material, or a polyvinylpyrrolidone fiber-forming material, and a second fiber comprising a blend of fiber-forming materials including a carboxyl-modified polyvinyl alcohol fiber-forming material, a sulfonate-modified polyvinyl alcohol fiber-forming material, a polyvinylpyrrolidone fiber-forming material, or a combination thereof, wherein the weight ratio of the carboxyl-modified polyvinyl alcohol fiber-forming material to the sulfonate and / or polyvinylpyrrolidone fiber-forming material is from about 3:1 to about 19:1.

[0015] Harsh chemicals include chemical species that are very acidic or alkaline, compounds that have a positive standard electrode potential, and / or compounds that are very hygroscopic so as to dry out moisture-containing materials.

[0016] Another aspect of the present disclosure provides a water soluble unit dose article comprising an outer wall having an outer surface and an inner surface defining an inner pouch volume, the outer wall comprising a water soluble nonwoven web as described herein, and a composition contained in the inner pouch volume. In an embodiment, the composition can include an irritating chemical.

[0017] Water-soluble unit dose articles according to the present disclosure can be designed to provide one or more advantages, such as retention of desirable nonwoven web properties such as elasticity and solubility in the presence of harsh chemicals, resistance to degradation in the presence of harsh chemicals, resistance to coloration, improved hand relative to pouches made from water-soluble films, reduced tendency to stick to other pouches and / or secondary packaging relative to pouches prepared from water-soluble films, and / or provide more uniform release and distribution of contents into bulk water compared to pouches prepared from water-soluble films.

[0018] Unless otherwise specified, all percentages, parts, and ratios referred to herein are based on the total dry weight of the fiber composition, nonwoven web composition, or, as the case may be, the total weight of the packet contents composition of the present disclosure, and all measurements are made at about 25° C. Unless otherwise specified, all such weights pertaining 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.

[0019] All ranges stated herein include all possible subsets of ranges and any combination of such subset ranges. Usually, unless otherwise stated, the range includes the stated endpoints. When a range of values ​​is provided, it is understood that each value between the upper and lower limits of the range, and any other stated or intervening values ​​of the stated range, are included within the scope of the disclosure. The upper and lower limits of these smaller ranges may be independently included in the smaller ranges, and are also included within the scope of the disclosure, subject to any specifically excluded limit in the stated range. When a stated range includes one or both of the limits, it is contemplated that ranges excluding either or both of the included limits are also part of the disclosure.

[0020] For example, for any numerical values ​​set forth herein as parameters of the described subject matter, or as part of a range relating to the described subject matter, the alternatives forming part of the description are expressly contemplated as functionally equivalent ranges surrounding the specific numerical value (e.g., for a dimension disclosed as "40 mm," an alternative embodiment contemplated is "about 40 mm").

[0021] As used herein, unless otherwise specified, the term "nonwoven web" refers to a web or sheet that includes, consists of, or consists essentially of fibers that are arranged and bonded together (e.g., by a carding process). Additionally, as used herein, "nonwoven web" includes any structure that includes a nonwoven web or sheet, including, for example, a nonwoven web or sheet that has a film laminated to its surface. Methods of preparing nonwoven webs from fibers are well known in the art, for example, as described in Nonwoven Fabrics Handbook, prepared by Ian Butler, edited by Subhash Batra et al., Printing by Design, 1999, which is incorporated herein by reference in its entirety. As used herein, unless otherwise specified, the term "film" refers to a continuous film or sheet, for example, prepared by a casting or extrusion process.

[0022] As used herein, unless otherwise specified, the term "water-soluble" refers to any fiber, nonwoven web, or film having a dissolution time of 300 seconds or less at a particular temperature, as determined according to MSTM-205, as described herein. For example, the dissolution time may be 200 seconds or less, 100 seconds or less, 60 seconds or less, or 30 seconds or less at temperatures of about 80°C, about 70°C, about 60°C, about 50°C, about 40°C, about 20°C, or about 10°C, as appropriate. In embodiments where the dissolution temperature is not specified, the water-soluble fiber, nonwoven web, or nonwoven composite article has a dissolution time of 300 seconds or less at a temperature not exceeding about 80°C. As used herein, unless otherwise specified, the term "cold water-soluble" refers to any fiber, nonwoven web, or nonwoven composite article having a dissolution time of 300 seconds or less at 10°C, as determined according to MSTM-205. For example, the dissolution time may be 200 seconds or less, 100 seconds or less, 60 seconds or less, or 30 seconds at 10° C., as appropriate. In embodiments, a "water-soluble film" means that at a thickness of 1.5 mils, the film dissolves in 300 seconds or less at a temperature not exceeding 80° C. For example, a water-soluble film of 1.5 mils (about 38 μm) thickness can have a dissolution time of 300 seconds or less, 200 seconds or less, 100 seconds or less, 60 seconds or less, or 30 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., according to MSTM-205.

[0023] As used herein, the terms packet(s) and pouch(s) should be considered interchangeable. In certain embodiments, the terms packet(s) and pouch(s) are preferably used to refer to a container made using a nonwoven web, with an enclosed material, for example in the form of a metered dose delivery system, and a fully sealed container, respectively. The sealed pouch can be made by any suitable method, including processes and features such as heat sealing, solvent welding, and adhesive sealing (for example by using a water-soluble adhesive), etc.

[0024] As used herein, unless otherwise specified, the terms "weight percent (wt.%)" and "weight percent (wt%)" are intended to refer to the composition of a particular element in "dry" (non-aqueous) weight parts of the total nonwoven web, including any residual moisture in the nonwoven web, or, as the context may require, in weight parts of the total composition or coating.

[0025] As used herein, unless otherwise specified, the term "PHR" ("phr") is intended to refer to the composition of a particular element in parts per 100 parts water soluble polymeric resin(s) (whether PVOH or other polymeric resin, unless otherwise specified) in a water soluble nonwoven web, or in a solution used to make the nonwoven web.

[0026] As used herein, "comprising" refers to various components, ingredients, or steps that can be used together in the practice of the present disclosure. Thus, the term "comprising" encompasses the more restrictive terms "consisting essentially of" and "consisting of". The present composition can comprise, consist essentially of, or consist of any of the necessary and optional elements disclosed herein. For example, a thermoformed packet may "consist essentially of" a nonwoven web as described herein due to the use of its thermoforming characteristics, but may include a nonwoven web that is not thermoformed (e.g., a lid portion) and optional markings, such as by inkjet printing, on the nonwoven web. The present disclosure illustratively disclosed herein may suitably be practiced in the absence of any element or step not specifically disclosed herein.

[0027] The nonwoven webs, pouches, and related methods of making and using are intended to include embodiments that include any combination of one or more of the additional optional elements, features, and steps further described below, unless otherwise stated.

[0028] The nonwoven web can be made by any suitable method, including carding, as is well known in the art, as described in Nonwoven Fabrics Handbook, prepared by Ian Butler, edited by Subhash Batra et al., Printing by Design, 1999, which is incorporated herein by reference in its entirety. Methods for forming containers, such as pouches, from nonwoven fabrics are known in the art. The nonwoven web can be used to form containers (pouches) by any suitable process, including vertical form, fill and seal (VFFS), or thermoforming. The nonwoven web can be sealed, for example, at the periphery of the container, by any suitable process, including, for example, solvent sealing or heat sealing of the nonwoven web layers. Advantageously, the nonwoven web of the present disclosure can exhibit preferential shrinkage in the presence of heat and / or water (e.g., moisture). Thus, the nonwoven web can be heat and / or water shrunk when formed into a packet. The pouch can be used, for example, to meter materials to be delivered to bulk water.

[0029] The nonwoven webs, pouches, and related methods of use are intended to include embodiments that include any combination of one or more of the additional optional elements, features, and steps further described below, unless otherwise stated.

[0030] Water-soluble fiber-forming materials

[0031] Generally, water-soluble nonwoven webs can include a plurality of fibers, including a single fiber-forming material or a blend of fiber-forming materials. In embodiments, the fiber-forming material is water-soluble. In embodiments, the fibers are water-soluble.

[0032] Generally, the fibers of the present disclosure include at least one polyvinyl alcohol fiber-forming material. Polyvinyl alcohol is a synthetic polymer that is generally prepared by alcoholysis, commonly referred to as hydrolysis or saponification, of polyvinyl acetate. Fully hydrolyzed PVOH, in which virtually all acetate groups have been converted to alcohol groups, is a strongly hydrogen-bonded, highly crystalline polymer that is soluble only in hot water above about 140°F (about 60°C). If a sufficient number of acetate groups remain after hydrolysis of polyvinyl acetate, i.e., the PVOH polymer is partially hydrolyzed, the polymer is less hydrogen-bonded, less crystalline, and generally soluble in cold water below about 50°F (about 10°C). Such partially hydrolyzed polymers are vinyl alcohol-vinyl acetate copolymers, i.e., PVOH copolymers, but are generally referred to as PVOH.

[0033] The polyvinyl alcohol may be a modified polyvinyl alcohol, e.g., a copolymer. The modified polyvinyl alcohol may include a copolymer or a higher polymer (e.g., a terpolymer) that includes one or more monomers in addition to the vinyl acetate / vinyl alcohol group. Optionally, the modification is neutral, e.g., provided by ethylene, propylene, N-vinylpyrrolidone, or other uncharged monomer species. Optionally, the modification is cationic, e.g., provided by positively charged monomer species. Optionally, the modification is anionic. Thus, in some embodiments, the polyvinyl alcohol includes an anionic modified polyvinyl alcohol. An anionic modified polyvinyl alcohol may include a partially or fully hydrolyzed PVOH copolymer that includes anionic monomer units, vinyl alcohol monomer units, and optionally vinyl acetate monomer units (i.e., if not fully hydrolyzed). In some embodiments, the PVOH copolymer may include two or more types of anionic monomer units. General classes of anionic monomer units that can be used for PVOH copolymers include vinyl polymerized units corresponding to vinyl sulfonic acid monomers and their esters, vinyl monocarboxylic acid monomers, their esters and anhydrides, dicarboxylic acid monomers having a polymerizable double bond, their esters and anhydrides, and the alkali metal salts of any of the foregoing.Examples of suitable anionic monomer units include vinyl acetate, maleic acid, monoalkyl maleates, dialkyl maleates, maleic anhydride, fumaric acid, monoalkyl fumarates, dialkyl fumarates, itaconic acid, monoalkyl itaconates, dialkyl itaconates, citraconic acid, monoalkyl citraconic acids, dialkyl citraconic acids, citraconic anhydride, mesaconic acid, monoalkyl mesaconic acids, dialkyl mesaconic acids, glutaconic acid, monoalkyl glutaconic acids, dialkyl glutaconic acids, glutaconic anhydride, acrylonitrile ... alkyl acrylates, alkyl alkacrylates, vinyl sulfonic acid, allyl sulfonic acid, ethylene sulfonic acid, 2-acrylamido-1-methylpropanesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid (AMPS), 2-methylacrylamido-2-methylpropanesulfonic acid, 2-sulfoethyl acrylate, alkali metal salts of the foregoing (e.g., sodium, potassium, or other alkali metal salts), esters of the foregoing (e.g., methyl, ethyl, or other C). 1 ~C 4 Or C 6 The vinyl polymerized units include those corresponding to vinyl anionic monomers, including alkyl esters, and combinations of the foregoing (e.g., multiple types of anionic monomers or equivalent forms of the same anionic monomer). In some embodiments, the PVOH copolymers can include two or more types of monomer units selected from neutral, anionic, and cationic monomer units.

[0034] The level of incorporation (degree of modification) of one or more anionic monomer units into the PVOH copolymer is not particularly limited. In an embodiment, the one or more anionic monomer units are present in the PVOH copolymer in an amount ranging from about 1 mol.% or 2 mol.% to about 6 mol.% or 10 mol.% (e.g., in various embodiments, at least 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, or 4.0 mol.%, and / or up to about 3.0, 4.0, 4.5, 5.0, 6.0, 8.0, or 10 mol.%). In an embodiment, the one or more anionic monomer units are present in the PVOH copolymer in an amount ranging from about 1 mol.% to 10 mol.%, or from about 1 mol.% to 8 mol.%, or from about 1 mol.% to 5 mol.%, from about 2 mol.% to about 6 mol.%, from about 3 mol.% to about 5 mol.%, or from about 1 mol.% to about 3 mol.%.

[0035] The degree of hydrolysis (DH) of the PVOH homopolymers and PVOH copolymers contained in the water-soluble fibers and nonwoven webs of the present disclosure can range from about 75% to about 99.9% (e.g., for cold water soluble compositions, about 79% to about 92%, about 80% to about 90%, about 88% to about 92%, about 86.5% to about 89%, or about 88%, 90% or 92%; about 90% to about 99%, about 92% to about 99%, about 95% to about 99%, about 98% to about 99%, about 98% to about 99.9%, about 96%, about 98%, about 99%, or more than 99%). DH is a measure of the amount of acetate that has been specifically removed from a polyvinyl acetate polymer (e.g., via hydrolysis, saponification), but is most commonly used to understand the amount of acetate remaining in the PVOH polymer or copolymer. The acetate groups form the amorphous or non-crystalline regions of the PVOH copolymer. Thus, it can be roughly stated that the higher the DH, the higher the relative crystallinity of the PVOH copolymer or blend of PVOH copolymers. When a PVOH resin is described as having (or not having) a particular DH, unless otherwise specified, the specified DH is intended to be the average DH for that PVOH resin.

[0036] Generally, as the degree of hydrolysis decreases, fibers or nonwoven webs made from the polymer will have less mechanical strength but faster solubility at temperatures below about 20°C. As the degree of hydrolysis increases, fibers or nonwoven webs made from the polymer tend to be mechanically stronger and less thermoformable. The degree of hydrolysis of the PVOH can be selected such that the water solubility of the polymer is temperature dependent, and thus the solubility of the fibers and / or nonwoven webs made from the polymer and additional components is also affected. In one alternative, the nonwoven web is cold water soluble. For copoly(vinyl acetate vinyl alcohol) polymers that do not contain any other monomers (e.g., homopolymers that are not copolymerized with anionic monomers), cold water soluble fibers or nonwoven webs that dissolve in water at temperatures below 10°C can 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 alternative, the fibers or nonwoven webs are hot water soluble. For copoly(vinyl acetate vinyl alcohol) polymers that do not contain any other monomers (e.g., homopolymers that are not copolymerized with anionic monomers), hot water soluble fibers or nonwoven webs that dissolve in water at temperatures of at least about 60° C. can include PVOH having a degree of hydrolysis of at least about 98%.

[0037] The degree of hydrolysis of the polymer blend is the arithmetically weighted average degree of hydrolysis.

number

number

number

[0038] The viscosity (μ) of the PVOH polymer is determined by measuring the freshly made solution using a Brookfield LV type viscometer with a UL adapter as described in the British Standard EN ISO 15023-2:2006 Annex E Brookfield Test method. It is international practice to state the viscosity of a 4% polyvinyl alcohol solution in water at 20°C. All viscosities specified in centipoise (cP) herein should be understood to refer to the viscosity of a 4% polyvinyl alcohol solution in water at 20°C, unless otherwise specified. Similarly, when a polymer is described as having (or not having) a particular viscosity, unless otherwise specified, the specified viscosity is intended to be the average viscosity for a polymer having essentially the corresponding molecular weight distribution, i.e., the weighted natural log average viscosity as described below. The viscosity of the PVOH polymer is determined by the weight average molecular weight of the PVOH polymer.

number

number

[0039] In embodiments, the PVOH resin may have a viscosity of about 1.0 to about 50.0 cPs, about 1.0 to about 40.0 cPs, or about 1.0 to about 30.0 cPs, such as about 4 cPs, 8 cPs, 15 cPs, 18 cPs, 23 cPs, or 26 cPs. In embodiments, the PVOH copolymer may have a viscosity of about 1.0 to about 30.0 cPs, such as about 1 cPs, 1.5 cPs, 2 cPs, 2.5 cPs, 3 cPs, 3.5 cPs, 4 cPs, 4.5 cPs, 5 cPs, 5.5 cPs, 6 cPs, 6.5 cPs, 7 cPs, 7.5 cPs, 8 cPs, 8.5 cPs, 9 cPs, 9.5 cPs, 10 cPs, 11 cPs, 12 cPs, 13 cPs, 14 cPs, 15 cPs, 16 cPs, 17 cPs, 18 cPs, 23 cPs, 26 cPs, 27 cPs, 28 cPs, 29 cPs, 30 cPs, 31 cPs, 32 cPs, 33 cPs, 34 cPs, 35 cPs, 36 cPs, 37 cPs, 38 cPs, 39 cPs, 40 cPs, 41 cPs, 42 cPs, 43 cPs, 44 cPs, 45 cPs, 46 cPs, 47 cPs, 48 ​​cPs, 49 cPs, 50 cPs, 5 The PVOH copolymer may have a viscosity of about 21 cPs to about 26 cPs. In embodiments, the PVOH copolymer may have a viscosity of about 5 cPs to about 14 cPs.

[0040] Polyvinyl alcohol can undergo changes in solubility characteristics. It is known to those skilled in the art that acetate groups in copoly(vinyl acetate vinyl alcohol) polymers (PVOH homopolymers) can be hydrolyzed by either acid or alkaline hydrolysis. As the degree of hydrolysis increases, polymer compositions made from PVOH homopolymers will have increased mechanical strength but reduced solubility at low temperatures (e.g., hot water temperatures are required for complete dissolution). Thus, exposure of PVOH homopolymers to an alkaline environment can transform the polymer from one that dissolves quickly and completely in a given aqueous environment (e.g., cold water medium) to one that dissolves slowly and / or incompletely in the aqueous environment, potentially resulting in undissolved polymeric residues.

[0041] PVOH copolymers with pendant carboxyl groups, such as maleate-modified PVOH, may form lactone rings between adjacent pendant carboxyl groups and alcohol groups, which may reduce the water solubility of the PVOH copolymer.In the presence of strong base, the lactone rings may open over several weeks in relatively warm (ambient) and humid conditions (e.g., via lactone ring-opening reaction to form corresponding pendant carboxyl and alcohol groups, increasing water solubility).Therefore, in contrast to the effect observed with PVOH homopolymers, it is believed that such PVOH copolymers may become more soluble during storage due to chemical interactions between the polymer and the alkaline composition in the pouch.

[0042] Certain sulfonates and their derivatives with polymerizable vinyl bonds can be copolymerized with vinyl acetate to provide cold water soluble PVOH polymers that are stable in the presence of strong base. The base catalyzed alcoholysis products of these copolymers, which can be used to formulate water soluble fibers, are fast soluble vinyl alcohol-sulfonate copolymers. The sulfonate groups in the PVOH copolymers may revert to sulfonic acid groups in the presence of hydrogen ions, but the sulfonic acid groups still provide the polymer with excellent cold water solubility. In embodiments, the vinyl alcohol-sulfonate copolymers do not contain residual acetate groups (i.e., are fully hydrolyzed), and therefore cannot be further hydrolyzed by either acid or alkaline hydrolysis. In general, water solubility increases with increasing amount of modification, and thus, when fully modified by sulfonate or sulfonic acid groups, hydrogen bonding and crystallinity are suppressed, making them soluble in cold water. In the presence of acidic or basic species, the copolymer is generally unaffected except for the sulfonate or sulfonic acid groups, and excellent cold water solubility is maintained even in the presence of acidic or basic species. Examples of suitable sulfonic acid comonomers (and / or their alkali metal salt derivatives) include vinyl sulfonic acid, allyl sulfonic acid, ethylene sulfonic acid, 2-acrylamido-1-methylpropanesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 2-methacrylamido-2-methylpropanesulfonic acid, and 2-sulfoethyl acrylate, with the sodium salt of 2-acrylamido-2-methylpropanesulfonic acid (AMPS) being the preferred comonomer.

[0043] Water-soluble polymers can be blended, whether they are polyvinyl alcohol polymers or not. When the polymer blend comprises a blend of polyvinyl alcohol polymers, the PVOH polymer blend can comprise a first PVOH polymer ("first PVOH polymer"), which can comprise a PVOH homopolymer or a PVOH copolymer (e.g., a PVOH ter (or higher copolymer) containing one or more types of anionic monomer units, and a second PVOH polymer ("second PVOH polymer"), which can comprise a PVOH homopolymer or a PVOH copolymer (e.g., a PVOH ter (or higher copolymer) containing one or more types of anionic monomer units. In some embodiments, the PVOH polymer blend comprises only the first PVOH polymer and the second PVOH polymer (e.g., a binary blend of two polymers). Alternatively or in addition, the PVOH polymer blend, or the fiber or nonwoven web made therefrom, can be characterized as being free or substantially free of other polymers (e.g., other water-soluble polymers in general, other PVOH-based polymers in particular, or both). As used herein, "substantially free" means that the first and second PVOH polymers account for at least 95%, at least 97%, or at least 99% by weight of the total amount of water-soluble polymers in the water-soluble fiber or nonwoven web. In other embodiments, the water-soluble fiber or nonwoven web can include one or more additional water-soluble polymers. For example, the PVOH polymer blend can 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 nonwoven web can include at least a third (or fourth, fifth, etc.) water-soluble polymer that is other than a PVOH polymer (e.g., other than a PVOH homopolymer or PVOH copolymer with or without anionic monomer units).

[0044] Water-soluble polymers other than PVOH polymers can include, but are not limited to, polyacrylates, water-soluble acrylate copolymers, polyvinylpyrrolidone, polyethyleneimine, pullulan, water-soluble natural polymers (including, but not limited to, guar gum, gum acacia, xanthan gum, carrageenan, and starch), water-soluble polymer derivatives (including, but not limited to, modified starch, ethoxylated starch, and hydroxypropylated starch), copolymers of the foregoing, and combinations of any of the foregoing. Still other water-soluble polymers can include polyalkylene oxides, polyacrylamides, polyacrylic acids and their salts, cellulose, cellulose ethers, cellulose esters, cellulose amides, polyvinyl acetates, polycarboxylic acids and their salts, polyamino acids, polyamides, gelatin, methylcellulose, carboxymethylcellulose and its salts, dextrins, ethylcellulose, hydroxyethylcellulose, hydroxypropylmethylcellulose, maltodextrins, polymethacrylates, and combinations of any of the foregoing. Such water-soluble polymers, whether PVOH or not, are commercially available from a variety of sources. In an embodiment, the fiber-forming material may include a carboxyl-modified polyvinyl alcohol. In an embodiment, the carboxyl-modified PVOH includes a maleate monomer unit selected from the group consisting of monomethyl maleate, maleic acid, maleic anhydride, alkali salts thereof, and combinations thereof. Thus, in an embodiment, the carboxyl-modified PVOH includes a maleate-modified PVOH. As used herein, unless otherwise specified, "maleate-modified PVOH" refers to a polyvinyl alcohol that includes a monomer unit resulting from polymerization with a monomer selected from the group consisting of maleic acid, monoalkyl maleate, dialkyl maleate, and / or maleic anhydride. In an embodiment, the maleate monomer unit may be monomethyl maleate.

[0045] In an embodiment, the maleate-modified PVOH is substantially free of lactone rings, such that the modified PVOH has about 2 pendant carboxylate groups per maleate monomer unit. In embodiments, the maleate-modified PVOH can include from about 1.5 to about 2 pendant carboxylate groups per maleate monomer unit, or from about 1.2 to about 2 pendant carboxylate groups per maleate monomer unit, or from about 1 to about 2 pendant carboxylate groups per maleate monomer unit, e.g., about 2 pendant carboxylate groups per maleate monomer unit, or about 1.9 pendant carboxylate groups per maleate monomer unit, or about 1.8 pendant carboxylate groups per maleate monomer unit, or about 1.7 pendant carboxylate groups per maleate monomer unit, or about 1.6 pendant carboxylate groups per maleate monomer unit, or about 1.5 pendant carboxylate groups per maleate monomer unit, or about 1.2 pendant carboxylate groups per maleate monomer unit, or about 1 pendant carboxylate group per maleate monomer unit.

[0046] In an embodiment, the fiber-forming material comprises a sulfonate-modified polyvinyl alcohol. In an embodiment, the sulfonate-modified PVOH is the only polyvinyl alcohol fiber-forming material that constitutes the fiber. In an embodiment, the nonwoven web is made of fibers in which the sulfonate-modified PVOH is the only fiber-forming material present. In an embodiment, the fiber-forming material comprises a sulfonate-modified PVOH and a cellulose fiber-forming material or a starch fiber-forming material. In an embodiment, the fiber-forming material comprises a sulfonate-modified PVOH and a polyvinylpyrrolidone, a carboxyl-modified PVOH comprising a carboxylated anionic monomer unit, or both. In an embodiment, the sulfonate-modified PVOH comprises a sulfonated anionic monomer unit selected from the group consisting of vinyl sulfonic acid, allyl sulfonic acid, ethylene sulfonic acid, 2-acrylamido-1-methylpropane sulfonic acid, 2-acrylamido-2-methylpropane sulfonic acid (AMPS), 2-methylacrylamido-2-methylpropane sulfonic acid, 2-sulfoethyl acrylate, alkali salts thereof, and combinations thereof. In an embodiment, the sulfonated anionic monomer unit is selected from the group consisting of 2-acrylamido-1-methylpropanesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid (AMPS), 2-methylacrylamido-2-methylpropanesulfonic acid, 2-sulfoethyl acrylate, alkali salts thereof, and combinations thereof. In an embodiment, the sulfonated anionic monomer unit is selected from the group consisting of 2-acrylamido-2-methylpropanesulfonic acid (AMPS), 2-methylacrylamido-2-methylpropanesulfonic acid, alkali salts thereof, and combinations thereof. In an embodiment, the sulfonated anionic monomer unit comprises AMPS. In an embodiment, the sulfonate modified PVOH fiber forming material has a degree of hydrolysis of at least 95%. In an embodiment, the sulfonate modified PVOH fiber forming material has a degree of hydrolysis ranging from 95% to 99.9%. In an embodiment, the sulfonated anionic monomer unit is present in an amount ranging from about 1 mol% to about 5 mol%. In embodiments, the sulfonated anionic monomer units are present in an amount ranging from about 1 mol % to about 3 mol %.

[0047] In general, the AMPS-modified PVOH copolymer or maleate-modified PVOH copolymer can be selected to provide one or more advantages. For example, AMPS- or maleate-modified PVOH can provide improved resistance to harsh chemicals, such as acids, oxidants, and bases, which can cause damage to PVOH nonwovens. Without intending to be bound by theory, it is believed that the AMPS modification can inhibit acid-induced crosslinking of PVOH, thereby reducing the solubility of the nonwoven in water, and the AMPS and / or maleate modification can inhibit acid / base-induced polyene formation (condensation reactions), which can cause undesirable yellowing of the nonwoven. Additionally, the AMPS and maleate modifications can provide one or more advantages to the resulting nonwoven, such as reduced crystalline regions in the nonwoven, which results in reduced dissolution time.

[0048] When the fiber-forming material comprises a PVOH copolymer containing an anionic monomer unit, the level of incorporation of one or more anionic monomer units into the PVOH copolymer is not particularly limited. In embodiments, the one or more anionic monomer units are present in the PVOH copolymer in an amount ranging from about 1 mol.% to about 10 mol.%, from about 1.5 mol.% to about 8 mol.%, from about 2 mol.% to about 6 mol.%, from about 3 mol.% to about 5 mol.%, or from about 1 mol.% to about 4 mol.% (e.g., in various embodiments, at least about 1.0, 1.5, 1.8, 2.0, 2.5, 3.0, 3.5, or 4.0 mol.%, and up to about 3.0, 4.0, 4.5, 5.0, 6.0, 8.0, or 10 mol.%). In embodiments, the anionic monomer comprises maleate monomer units, and the maleate monomer units are present in an amount ranging from about 1 mol% to 10 mol%, or from about 1 mol% to 8 mol%, or from about 1 mol% to 5 mol%. In embodiments, the anionic monomer comprises maleate monomer units, and the maleate monomer units are present in an amount ranging from about 1 mol% to 5 mol%. In embodiments, the anionic monomer comprises sulfonated anionic monomer units, and the sulfonated anionic monomer units are present in an amount ranging from about 1 mol% to 10 mol%, or from about 1 mol% to 8 mol%, or from about 1 mol% to 5 mol%. In embodiments, the anionic monomer comprises sulfonated anionic monomer units, and the sulfonated anionic monomer units are present in an amount ranging from about 1 mol% to 5 mol%.

[0049] Polyvinylpyrrolidone is a synthetic resin made by polymerizing the monomer N-vinylpyrrolidone. There has been a great deal of research devoted to determining the molecular weight of PVP polymers. Low molecular weight polymers have a narrower distribution curve of molecular mass than higher molecular weight compounds. Some of the techniques for measuring the molecular weight of various PVP polymer products are based on measuring sedimentation, light scattering, osmometry, NMR spectroscopy, ebulliometry, and size exclusion chromatography to determine the absolute molecular weight distribution. By using these methods, one can measure any one of three molecular weight parameters: number average (Mn), viscosity average (Mv), and weight average (Mw). Each of these characteristics can produce a different response for the same polymer. Therefore, in any literature survey, one must know which molecular average is being cited.

[0050] In embodiments, the polyvinylpyrrolidone has a weight average molecular weight of at least about 3,000 g / mol.

number

number

number

number

number

[0051] Without intending to be bound by theory, it is believed that the high Mw PVP polymers disclosed herein are advantageous because they resist migrating out of the nonwoven when the nonwoven comes into contact with dry and / or hygroscopic components. It is believed that the higher the Mw, the more the individual polymer chains can intertwine, making it less likely that the PVP chains will separate from other components of the nonwoven and migrate out of the film.

[0052] PVP polymers can provide several advantages when added as a fiber-forming material to the fibers of the nonwoven webs described herein. For example, and not intending to be bound by theory, it is believed that the pyrrolidone functionality of the PVP polymer can protect against H2O from harsh chemicals. +It can act as an acid trap and / or pH buffer reacting with ions (shown in Scheme 1 below), which is believed to prevent acid-induced crosslinking and discoloration of polyvinyl alcohol. Additionally, PVOH homopolymer or copolymer nonwoven webs in contact with irritating chemicals typically become embrittled over time as the irritating chemicals wick water and / or plasticizers from the nonwoven web. The irritating chemicals can be hygroscopic, which can lead to the absorption of materials such as other polar solvents and those commonly used as plasticizers. However, advantageously, the combination of PVOH copolymer and PVP in the fiber-forming materials described herein can help prevent the nonwoven web from becoming embrittled in the presence of irritating chemicals. The PVP in the nonwoven webs described herein can act similarly to a plasticizer, but is resistant to wicking from the nonwoven web by irritating chemicals. PVP can also enable the nonwoven webs herein to remain flexible, even when the film contains relatively small amounts of traditional plasticizer and water content.

[0053] Scheme 1 [ka]

[0054] As described herein, the combination of sulfonate-modified PVOH and carboxyl-modified PVOH can advantageously provide resistance to degradation in the presence of aggressive chemicals, such as acids, oxidants, or bases.

[0055] As described herein, sulfonate-modified PVOH can advantageously provide resistance to degradation of nonwoven fabrics in the presence of aggressive chemicals, such as base-mediated oxidants. As used herein, the term "base-mediated oxidants" refers to oxidants that oxidize another chemical species using a basic mechanism of oxidation pathway. A basic mechanism of oxidation pathway is: -It refers to a pathway in which a base, such as OH, initiates or catalyzes the oxidation reaction of a reagent. For example, sodium hypochlorite, calcium hypochlorite, and monovalent and divalent salts with similar structures to sodium hypochlorite and calcium hypochlorite are considered base-mediated oxidants.

[0056] As described herein, the combination of PVOH and PVP can advantageously provide resistance to degradation in the presence of irritating chemicals, such as acids, oxidizing agents, or bases. For example, when using PVOH as the sole resin, the irritating chemicals may react with the PVOH and cause the nonwoven web to rapidly degrade. In contrast, it has been advantageously found that the combination of PVOH and PVP can stop or at least slow down the degradation of the nonwoven web. Without intending to be bound by theory, it is believed that the pyrrolidone functional groups of PVP act as acid traps, trapping H from the irritating chemicals. + ions to cause the acid-catalyzed elimination of the hydroxyl units of vinyl alcohol, + It is believed that the ions prevent the promotion of polyvinyl alcohol degradation, which may prevent the degradation of polyvinyl alcohol. Conventional water-soluble PVOH films have a tendency to degrade in the presence of harsh chemicals, such as chlorinated germicides, as well as other oxidizing chemicals, acids, and certain bases. Excessive oxidation renders the film insoluble in water and therefore ineffective for unit dose packaging. Without intending to be bound by theory, it is believed that hypochlorite ions generated by certain harsh chemicals oxidize pendant -OH moieties in PVOH copolymer films, resulting in carbonyl groups in the polymer backbone. Carbonyl groups are intermediate steps toward polyene formation (and yellowing) because they produce acidic alpha hydrogens. Carbonyl groups are also intermediates to chain scission. In addition, hydrochloric acid generated by certain harsh chemicals can react with hydroxyl groups to produce unsaturated bonds in the polymer backbone, which may result in reduced water solubility and discoloration of the film. In either event, removal of the pendant -OH groups renders the film increasingly insoluble in water.

[0057] A nonwoven web comprising a typical PVOH homopolymer or copolymer as the sole fiber-forming material in contact with an irritating chemical advantageously does not become embrittled due to migration of residual water out of the nonwoven web in the presence of the irritating chemical, however, such loss of water may result in shrinkage of the fibers and ultimately the nonwoven web.More advantageously, the sulfonate-modified PVOH and / or PVP can act similarly as a rheology modifier for the carboxyl-modified PVOH, thereby controlling the flow of fiber-forming materials during fiber formation and imparting chemical compatibility to the carboxyl-modified PVOH in the presence of irritating chemicals by inhibiting degradation of the carboxyl-modified PVOH by the irritating chemicals.

[0058] The water-soluble nonwoven webs described herein may include a carboxyl-modified PVOH fiber-forming material, and the sulfonate-modified PVOH and / or polyvinylpyrrolidone fiber-forming materials may be provided in a weight ratio of about 3:1 to about 19:1, respectively. In embodiments, the weight ratio of the carboxyl-modified PVOH fiber-forming material to the sulfonate-modified PVOH and / or polyvinylpyrrolidone fiber-forming material is about 3:1 to about 18.2, about 3:1 to about 17:1, about 5:1 to about 15:1, about 5:1 to about 12:1, about 5:1 to about 9:1, about 6:1 to about 9:1, or about 6.5:1 to about 7.5:1, respectively, by weight. In embodiments, the weight ratio of carboxyl-modified PVOH fiber-forming material to sulfonate-modified PVOH and / or polyvinylpyrrolidone fiber-forming material is from about 5:1 to about 15:1, from about 5:1 to about 12:1, from about 5:1 to about 9:1, from about 6:1 to about 9:1, from about 6.5:1 to about 7.5:1, from about 3:1 to about 6.5:1, or from about 3:1 to about 5:1, by weight, respectively.

[0059] In embodiments, the water-soluble nonwoven webs disclosed herein may include a plurality of fibers comprising a blend of fiber-forming materials including (i) polyvinylpyrrolidone and (ii) sulfonate-modified PVOH, carboxyl-modified PVOH, or both. In embodiments, the weight ratio of the polyvinylpyrrolidone fiber-forming material to the sulfonate-modified PVOH fiber-forming material, the carboxyl-modified PVOH fiber-forming material, or both, respectively, is from about 1:1 to about 1:19 by weight. In embodiments, the weight ratio of the polyvinylpyrrolidone fiber-forming material to the sulfonate-modified PVOH fiber-forming material, the carboxyl-modified PVOH fiber-forming material, or both, respectively, is from about 1:3 to about 1:19 by weight, from about 1:5 to about 1:15 by weight, from about 1:5 to about 1:12 by weight, from about 1:5 to about 1:9 by weight, from about 1:6 to about 1:9 by weight, or from about 1:6.5 to about 1:7.5 by weight.

[0060] Water-soluble nonwoven web

[0061] The water-soluble nonwoven web of the present disclosure generally comprises a plurality of water-soluble fibers. A nonwoven web generally refers to an arrangement of fibers bonded together, where the fibers are neither woven nor knitted. Generally, the plurality of water-soluble fibers can be arranged in any orientation. In an embodiment, the plurality of water-soluble fibers are randomly arranged (i.e., have no orientation). In an embodiment, the plurality of water-soluble fibers are arranged in a unidirectional orientation. In an embodiment, the plurality of water-soluble fibers are arranged in a bidirectional orientation. In some embodiments, the plurality of water-soluble fibers are multidirectional and have different arrangements in different areas of the nonwoven web.

[0062] In general, the fibers in any given nonwoven web can comprise any of the fiber-forming materials disclosed herein. The nonwoven web can comprise (1) a single fiber type comprising a single fiber-forming material, (2) a single fiber type comprising a blend of fiber-forming materials, (3) a blend of fiber types where each fiber type comprises a single fiber-forming material, (4) a blend of fiber types where each fiber type comprises a blend of fiber-forming materials, or (5) a blend of fiber types where each fiber type comprises a single fiber-forming material or a blend of fiber-forming materials. In embodiments comprising a blend of fiber types, the different fiber types can have different diameters, lengths, toughness, shape, stiffness, elasticity, solubility, melting points, glass transition temperatures (T g ), fiber forming material chemistry, color, or a combination thereof.

[0063] In an embodiment, the plurality of water-soluble fibers comprises a polyvinyl alcohol polymer. In a refinement of the above embodiment, the water-soluble fiber comprises a PVOH copolymer. In an embodiment, the water-soluble fiber comprises a single PVOH copolymer resin. In an embodiment, the water-soluble fiber comprises a blend of fiber-forming materials comprising a blend of polyvinyl alcohol polymers. In an embodiment, the water-soluble fiber comprises a blend of fiber-forming materials comprising a blend of polyvinyl alcohol polymers and PVP polymers. In an embodiment, the water-soluble polymer comprises two or more PVOH copolymers and a PVP polymer.

[0064] In an embodiment, the nonwoven web may include a plurality of fibers comprising a sulfonate-modified PVOH fiber-forming material that includes sulfonated anionic monomer units. In an embodiment, the sulfonate-modified PVOH fiber-forming material has a degree of hydrolysis of at least 95%. In an embodiment, the sulfonated anionic monomer is present in an amount ranging from about 1 mol % to about 5 mol %.

[0065] In embodiments, the nonwoven webs or unit doses described herein, including fibers including sulfonate-modified PVOH, such as AMPS-modified PVOH, having a degree of hydrolysis of at least 95% and in which the sulfonated anionic monomer is present in an amount ranging from about 1 mol% to about 5 mol%, can provide one or more advantages, such as improved resistance to harsh chemicals, such as base-mediated oxidants, that cause the nonwoven web to degrade. Additionally, the sulfonate-modified PVOH fiber-forming materials can provide nonwoven webs with good long-term storage properties (e.g., maintenance of dissolution properties and resistance to discoloration) as determined by exposing the web to a base-mediated oxidant composition, such as calcium hypochlorite, at 38° C. and 80% RH atmosphere for 6 weeks. Such webs exhibit a disintegration time of not more than 300 seconds in water at 23° C. according to MSTM 205, and / or a b of not more than 3.5, or not more than 3.0. * The 38° C. and 80% RH atmosphere can be maintained by packaging the water-soluble nonwoven web in contact with a base-mediated oxidizing agent in a secondary package prepared from 4 mil high density polyethylene (HDPE) film.

[0066] In an embodiment, the nonwoven web may include a plurality of fibers comprising a blend of fiber-forming materials including (i) polyvinylpyrrolidone and (ii) a sulfonate-modified PVOH, a carboxyl-modified PVOH, or both. In an embodiment, the blend of fiber-forming materials may include polyvinylpyrrolidone and a sulfonate-modified PVOH. In an embodiment, the blend of fiber-forming materials may include polyvinylpyrrolidone and a carboxyl-modified PVOH. In an embodiment, the blend of fiber-forming materials may include polyvinylpyrrolidone, a sulfonate-modified PVOH, and a carboxyl-modified PVOH.

[0067] In embodiments, the nonwoven webs or unit doses described herein comprising polyvinylpyrrolidone and fibers comprising carboxyl-modified PVOH fiber-forming materials, sulfonate-modified PVOH, or a combination of both, can provide one or more advantages. For example, improved resistance to harsh chemicals, such as acids, oxidants, and bases, that cause damage to the nonwoven web. Additionally, the combination can provide a nonwoven web with good long-term storage properties (e.g., maintenance of dissolution properties and resistance to discoloration) as determined by exposing the web to a trichloroisocyanuric acid (TCCA) or sodium bisulfate (SBS) composition at 38° C. and 80% RH atmosphere for 8 weeks. Such webs exhibit a disintegration time of no more than 300 seconds in water at 23° C. according to MSTM 205, leave no more than 50% nonwoven web residue based on the surface area of ​​the starting nonwoven web and the nonwoven web after testing in water at 23° C. according to MSTM 205, and / or have a b of no more than 3.5. * The 38°C and 80% RH atmosphere can be maintained by packaging the water-soluble nonwoven web in contact with the irritating chemical in a secondary package prepared from 4 mil high density polyethylene (HDPE) film.

[0068] In an embodiment, the water soluble nonwoven web comprises: (a) a blend of fiber-forming materials comprising (i) carboxyl-modified PVOH and (ii) sulfonate-modified PVOH, PVP, or both; (b) (iii) a blend of fibers comprising fibers that comprise a carboxyl-modified PVOH fiber-forming material and (iv) fibers that comprise a sulfonate-modified PVOH fiber-forming material, a PVP fiber-forming material, or both types of fibers; or (c) a blend of fibers comprising (v) a first fiber comprising a carboxyl-modified PVOH fiber-forming material, a sulfonate-modified PVOH fiber-forming material, or a PVP fiber-forming material, and (vi) a second fiber comprising a blend of fiber-forming materials comprising a carboxyl-modified PVOH fiber-forming material, a sulfonate-modified PVOH fiber-forming material, a PVP fiber-forming material, or a combination thereof. and In any of (a), (b), and (c), the weight ratio of the carboxyl-modified PVOH fiber-forming material to the sulfonate-modified PVOH and / or PVP fiber-forming material is from about 3:1 to about 19:1, by weight, respectively.

[0069] In an embodiment, the blend of fiber-forming materials (a) can include (i) a maleate-modified PVOH fiber-forming material and (ii) a sulfonate-modified PVOH fiber-forming material. In an embodiment, the blend of fiber-forming materials (a) can include (i) a maleate-modified PVOH fiber-forming material and (ii) a PVP fiber-forming material. In an embodiment, the blend of fiber-forming materials (a) can include (i) a maleate-modified PVOH fiber-forming material and (ii) a sulfonate-modified PVOH fiber-forming material and a PVP fiber-forming material. In an embodiment, the blend of fiber-forming materials (a) can include (ii) a PVP fiber-forming material. In a refinement of the previous embodiment, the sulfonate-modified PVOH fiber-forming material comprises AMPS.

[0070] In an embodiment, the blend of fibers (b) can include fibers comprising (iii) a maleate-modified PVOH fiber-forming material and fibers comprising (iv) a sulfonate-modified PVOH fiber-forming material. In an embodiment, the blend of fibers (b) can include fibers comprising (iii) a maleate-modified PVOH fiber-forming material and fibers comprising (iv) a PVP fiber-forming material, and in an embodiment, the blend of fibers (b) can include fibers comprising (iii) a maleate-modified PVOH fiber-forming material and fibers comprising (iv) a sulfonate-modified PVOH fiber-forming material and fibers comprising a PVP fiber-forming material. In an embodiment, the blend of fibers (b) can include fibers comprising (iv) a PVP fiber-forming material. In a refinement of the above embodiment, the sulfonate-modified PVOH fiber-forming material comprises AMPS.

[0071] In an embodiment, the fiber blend (c) can include (v) a first fiber comprising a carboxyl-modified PVOH fiber-forming material and (vi) a second fiber comprising a blend of fiber-forming materials comprising a carboxyl-modified PVOH fiber-forming material and a sulfonate-modified PVOH fiber-forming material. In an embodiment, the fiber blend (c) can include (v) a first fiber comprising a carboxyl-modified PVOH fiber-forming material and (vi) a second fiber comprising a blend of fiber-forming materials comprising a carboxyl-modified PVOH fiber-forming material and a PVP fiber-forming material. In an embodiment, the fiber blend (c) can include (v) a first fiber comprising a carboxyl-modified PVOH fiber-forming material and (vi) a second fiber comprising a blend of fiber-forming materials comprising a carboxyl-modified PVOH fiber-forming material, a sulfonate-modified PVOH fiber-forming material, and a PVP fiber-forming material. In an embodiment, the fiber blend (c) can include (vi) a second fiber comprising a PVP fiber-forming material. In a refinement of the above embodiment, the carboxyl-modified PVOH comprises maleate-modified PVOH and the sulfonate-modified PVOH fiber-forming material comprises AMPS.

[0072] In an embodiment, the fiber blend (c) can include (v) a first fiber comprising a sulfonate-modified PVOH fiber-forming material and (vi) a second fiber comprising a blend of fiber-forming materials comprising a carboxyl-modified PVOH fiber-forming material and a sulfonate-modified PVOH fiber-forming material. In an embodiment, the fiber blend (c) can include (v) a first fiber comprising a sulfonate-modified PVOH fiber-forming material and (vi) a second fiber comprising a blend of fiber-forming materials comprising a carboxyl-modified PVOH fiber-forming material and a PVP fiber-forming material, or a combination thereof. In an embodiment, the fiber blend (c) can include (v) a first fiber comprising a sulfonate-modified PVOH fiber-forming material and (vi) a second fiber comprising a blend of fiber-forming materials comprising a carboxyl-modified PVOH fiber-forming material, a sulfonate-modified PVOH fiber-forming material, and a PVP fiber-forming material. In a refinement of the above embodiment, the carboxyl-modified PVOH comprises maleate-modified PVOH and the sulfonate-modified PVOH fiber-forming material comprises AMPS.

[0073] In an embodiment, the blend of fibers (c) can include (v) a first fiber comprising a PVP fiber-forming material and (vi) a second fiber comprising a blend of fiber-forming materials comprising a carboxyl-modified PVOH fiber-forming material and a sulfonate-modified PVOH fiber-forming material. In an embodiment, the blend of fibers (c) can include (v) a first fiber comprising a PVP fiber-forming material and (vi) a second fiber comprising a blend of fiber-forming materials comprising a carboxyl-modified PVOH fiber-forming material and a PVP fiber-forming material. In an embodiment, the blend of fibers (c) can include (v) a first fiber comprising a PVP fiber-forming material and (vi) a second fiber comprising a blend of fiber-forming materials comprising a carboxyl-modified PVOH fiber-forming material, a sulfonate-modified PVOH fiber-forming material, and a PVP fiber-forming material. In a refinement of the previous embodiment, the carboxyl-modified PVOH comprises maleate-modified PVOH and the sulfonate-modified PVOH fiber-forming material comprises AMPS.

[0074] In embodiments, the water-soluble nonwoven webs described herein that include sulfonate-modified PVOH fiber-forming materials, such as AMPS-modified PVOH, or carboxyl-modified PVOH fiber-forming materials, such as maleate-modified PVOH, or PVP fiber-forming materials, can be selected to provide one or more advantages. In embodiments, blends of fibers and / or fiber-forming materials that include maleate-modified PVOH and AMPS-modified PVOH, PVP, or combinations thereof, can provide improved resistance to harsh chemicals, such as acids, oxidants, and bases, that can cause damage to water-soluble nonwovens.

[0075] In embodiments, the water-soluble nonwoven webs or unit doses described herein that include fibers that include a combination of carboxyl-modified PVOH fiber-forming materials and sulfonate-modified PVOH and / or PVP fiber-forming materials can provide one or more advantages. For example, improved resistance to harsh chemicals, such as acids, oxidants, and bases, that cause damage to water-soluble films. Additionally, the combination can provide a water-soluble web that has good long-term storage properties, as determined by exposing the web to a trichloroisocyanuric acid (TCCA) or sodium bisulfate (SBS) composition at 38° C. and 80% RH atmosphere for 8 weeks. Such webs exhibit a disintegration time of no more than 300 seconds in water at 23° C. according to MSTM 205, leave no more than 50% of the nonwoven web residue, maintain an average elongation of at least 90%, and / or have a b of no more than 3.5, based on the surface area of ​​the starting nonwoven web and the nonwoven web after testing according to MSTM 205 in water at 23° C. * The 38°C and 80% RH atmosphere was maintained by packaging the water-soluble nonwoven web in contact with the irritating chemicals in a secondary package prepared from 4 mil high density polyethylene (HDPE) film.

[0076] The nonwoven web may further comprise fibers comprising fiber-forming materials including, but not limited to, polyvinyl alcohol (e.g., carboxyl-modified PVOH containing carboxylated anionic monomer units), polyvinylpyrrolidone, water-soluble acrylate copolymers, polyethyleneimine, pullulan, water-soluble natural polymers including, but not limited to, guar gum, gum acacia, xanthan gum, carrageenan, and starch, water-soluble polymer modified starch, copolymers of the foregoing, or any combination of the foregoing. Still other water-soluble polymers may include polyalkylene oxides, polyacrylamides, 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, or any combination of the foregoing. Such water-soluble polymers are commercially available from a variety of sources. In one type of embodiment, the type and / or amount of the additional polymer(s) does not result in a water-soluble nonwoven web that is less resistant to irritating chemicals. In an embodiment, (a) a plurality of the plurality of fibers further comprises fibers comprising cellulose, starch, carboxyl-modified PVOH comprising carboxylated anionic monomer units, or combinations thereof, (b) a plurality of fibers comprising sulfonate-modified PVOH fiber-forming material further comprises fiber-forming material comprising cellulose, starch, polyvinylpyrrolidone, carboxyl-modified PVOH comprising carboxylated anionic monomer units, or combinations thereof, or (c) a combination of (a) and (b). In an embodiment, the plurality of fibers can further comprise fibers comprising cellulose, starch, carboxyl-modified PVOH comprising carboxylated anionic monomer units, or combinations thereof.In an embodiment, the plurality of fibers may include fibers comprising a blend of a sulfonate-modified PVOH fiber-forming material and a fiber-forming material comprising cellulose, starch, polyvinylpyrrolidone, a carboxyl-modified PVOH containing carboxylated anionic monomer units, or a combination thereof. In an embodiment, the cellulose may include cellulose, carboxymethylcellulose (CMC), hydroxymethylcellulose (HMC), hydropropylmethylcellulose (HPMC), hydroxyethylcellulose (HEC), hydroxypropylcellulose (HPC), methylcellulose, ethylcellulose, ethylmethylcellulose, salts of the foregoing, or combinations of the foregoing. In an embodiment, the cellulose may include sodium carboxymethylcellulose (CMC). In an embodiment, the CMC may have a substitution of about 20% to about 60%.

[0077] The water soluble fibers and / or water soluble nonwoven webs may contain other auxiliary and treating agents, such as, but not limited to, plasticizers, plasticizer compatibilizers, surfactants, colorants, acid scavengers, lubricants, release agents, fillers, extenders, crosslinking agents, antiblocking agents, antioxidants, detackifying agents, and the like. The composition may contain, in amounts suitable for the intended purpose, antifoaming agents, nanoparticles such as layered silicate nanoclays (e.g., sodium montmorillonite), bleaching agents (e.g., sodium metabisulfite, sodium bisulfate, or others), aversive agents such as bittering agents (e.g., denatonium salts such as denatonium benzoate, denatonium saccharin, and denatonium chloride; sucrose octaacetate; quinine; flavonoids such as quercetin and naringen; and quassinoids such as cassine and brucine), and irritants (e.g., capsaicin, piperine, allyl isothiocyanate, and resiniferatoxin), cellulose, starch, and other functional ingredients. Specific such auxiliary and processing agents may be selected from those suitable for use in water-soluble fibers or those suitable for use in water-soluble nonwoven webs.

[0078] In an embodiment, the water soluble fibers and / or the nonwoven web comprise cellulose, starch, or a combination thereof. In an embodiment, the water soluble fibers and / or the nonwoven web comprise cellulose. In an embodiment, the water soluble fibers and / or the nonwoven web comprise starch.

[0079] In an embodiment, the water-soluble fibers and water-soluble nonwoven webs are free of auxiliary agents. As used herein, unless otherwise specified, "auxiliary-free" with respect to fibers means that the fibers contain less than about 0.01% by weight, less than about 0.005% by weight, or less than about 0.001% by weight of auxiliary agents, based on the total weight of the fibers. As used herein, unless otherwise specified, "auxiliary-free" with respect to nonwoven webs means that the nonwoven web contains less than about 0.01% by weight, less than about 0.005% by weight, or less than about 0.001% by weight of auxiliary agents, based on the total weight of the nonwoven web. In an embodiment, the water-soluble fibers contain a plasticizer. In an embodiment, the water-soluble fibers contain a surfactant. In an embodiment, the nonwoven web contains a plasticizer. In an embodiment, the nonwoven web contains a surfactant. In an embodiment, the water-soluble fibers contain no auxiliary agents other than plasticizers, surfactants, cellulose, starch, or combinations thereof. In embodiments, the water-soluble nonwoven web does not contain any auxiliary materials other than plasticizers, surfactants, cellulose, starch, or combinations thereof.

[0080] A plasticizer is a liquid, solid, or semi-solid that is added to a material (usually a resin or elastomer) to make it softer, more flexible (by lowering the glass transition temperature of the polymer), and easier to process. Alternatively, the polymer can be plasticized internally by chemically modifying the polymer or monomer. Additionally or alternatively, the polymer can be plasticized externally by the addition of a suitable plasticizer. Water is recognized as a very efficient plasticizer for PVOH and other polymers, including but not limited to water-soluble polymers, but its volatility limits its usefulness because polymeric nonwoven webs must have at least some resistance (robustness) to a variety of ambient conditions, including low and high relative humidity.

[0081] Plasticizers may include, but are not limited to, glycerin, diglycerin, sorbitol, ethylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, tetraethylene glycol, propylene glycol, polyethylene glycols up to 400 MW, neopentyl glycol, trimethylolpropane, polyether polyols, 2-methyl-1,3-propanediol (MPDiol®), ethanolamine, maltitol, and mixtures thereof. In embodiments, the plasticizer is selected from the group consisting of glycerol, maltitol, trimethylolpropane, or combinations thereof. The total amount of non-aqueous plasticizer provided in the fibers can be in the range of about 1% to about 45% by weight, or about 5% to about 45% by weight, or about 10% to about 40% by weight, or about 20% to about 30% by weight, about 1% to about 4% by weight, or about 1.5% to about 3.5% by weight, or about 2.0% to about 3.0% by weight, for example, about 1% by weight, about 2.5% by weight, about 5% by weight, about 10% by weight, about 15% by weight, about 20% by weight, about 25% by weight, about 30% by weight, about 35% by weight, or about 40% by weight, based on the total fiber weight.

[0082] Surfactants for use on fibers are well known in the art. Optionally, a surfactant is included to aid in dispersion of the fibers during carding. Surfactants suitable for the fibers of the present disclosure include, but are not limited to, dialkyl sulfosuccinates, lactylated fatty acid esters of glycerol and propylene glycol, lactylic 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, quaternary amines, alkali metal salts of higher fatty acids containing about 8 to 24 carbon atoms, alkyl polyethylene glycol ethers, alkyl sulfates, alkyl polyethoxylate sulfates, alkyl benzene sulfonates, monoethanolamines, lauryl alcohol ethoxylates, propylene glycol, diethylene glycol, cocamide, salts thereof, and combinations of any of the foregoing. In embodiments, the surfactant comprises a quaternary amine, myristyl dimethylamine oxide, an alkyl polyethylene glycol ether, a cocamide, or a combination thereof.

[0083] 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 glycols 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 polyethoxylate sulfates and alkylbenzene sulfonates (anionic), and amine oxides, N-alkyl betaines and sulfobetaines (zwitterionic). Other suitable surfactants include dioctyl sodium sulfosuccinate, lactylated fatty acid esters of glycerin and propylene glycol, lactylated esters of fatty acids, sodium alkyl sulfates, polysorbate 20, polysorbate 60, polysorbate 65, polysorbate 80, lecithin, acetylated fatty acid esters of glycerin and propylene glycol, and acetylated esters of fatty acids, and combinations thereof. In various embodiments, the amount of surfactant in the fiber ranges from about 0.01% to about 2.5%, from about 0.1% to about 2.5%, from about 1.0% to about 2.0%, from about 0.01% to 0.25%, or from about 0.10% to 0.20% by weight.

[0084] In certain embodiments, the surfactants used in the water-soluble films can be quaternary ammonium surfactants or other surfactants that are basic and contain hindered amine characteristics, and can advantageously provide antioxidant protection from harsh chemicals. For example, myristyl (C 14 ) Dimethylamine oxide, dioctyldimethylammonium chloride salts, or combinations thereof can provide advantageous antioxidant protection to the film.

[0085] In embodiments, the water-soluble nonwoven web herein can further comprise one or more acid scavengers and / or antioxidants.It is believed that the acid scavengers and / or antioxidants reduce the damaging effect of the composition on the water-soluble nonwoven web, such as reducing the degradation of the water-soluble nonwoven web, or reducing the yellowing of the water-soluble nonwoven web, or maintaining the tensile strength of the water-soluble nonwoven web.Furthermore, without intending to be bound by theory, it is believed that the inclusion of the acid scavengers or antioxidants helps to reduce the amount of acid in the nonwoven web environment, which can mitigate acid-catalyzed hydrolysis and condensation reactions and promote the oxidative activity of hypochlorite in the form of hypochlorous acid.

[0086] In embodiments, the acid scavenger can include one or more of N-vinylpyrrolidone, sodium metabisulfite, activated olefins, maleate molecules (e.g., maleic acid and its derivatives), allylic compounds (e.g., allylic alcohols, allylic acetates, etc.), ethylene-containing compounds, quaternary ammonium compounds, amines (e.g., pyridine, monoethanolamine, methylamine, aniline), and tertiary amine-containing compounds. The acid scavenger can be included in the films described herein in an amount ranging from about 0.25 PHR to about 15 PHR, for example, about 0.25 PHR, about 1 PHR, about 1.5 PHR, about 2 PHR, about 3 PHR, about 4 PHR, about 5 PHR, about 5.5 PHR, about 6 PHR, about 6.5 PHR, about 7 PHR, about 8 PHR, about 9 PHR, about 10 PHR, or about 15 PHR.

[0087] In embodiments, the acid scavenger can be provided in or on the fibers, in or on the nonwoven web, or both. In embodiments, the acid scavenger can be coated on the fibers, coated on the nonwoven web, or both. In embodiments, the acid scavenger can be dispersed throughout the nonwoven web. The acid scavenger can be adsorbed to the fibers throughout the nonwoven web or bound by electrostatic forces. For example, the acid scavenger can be added as the fibers are being laid so that the acid scavenger is provided throughout the nonwoven web. In embodiments, the acid scavenger can be provided to the fiber-forming material during processing so that the acid scavenger is provided to the fibers themselves.

[0088] In an embodiment, the water-soluble nonwoven web may further comprise an antioxidant, such as a chloride scavenger. For example, suitable antioxidants / chloride scavengers include sulfites, bisulfites, thiosulfates, thiosulfates, iodides, nitrites, carbamates, ascorbates, and combinations thereof. In an embodiment, the antioxidant is selected from propyl gallate (PGA), gallic acid, citric acid (CA), sodium metabisulfite (SMBS), carbamates, ascorbates, and combinations thereof. In an embodiment, the antioxidant is selected from the group consisting of sodium metabisulfite, propyl gallate, gallic acid, phenolic compounds, hindered amines, citric acid, zinc acetate, and combinations thereof. In an embodiment, the antioxidant may be selected from the group consisting of propyl gallate, gallic acid, phenolic compounds, hindered amines, sodium metabisulfite, zinc acetate, and combinations thereof. The antioxidant can be present in the nonwoven web in an amount ranging from about 0.25 to about 10 PHR, for example, about 0.25 PHR, about 1 PHR, about 1.5 PHR, about 2 PHR, about 3 PHR, about 4 PHR, about 5 PHR, about 5.5 PHR, about 6 PHR, about 6.5 PHR, about 7 PHR, about 8 PHR, about 9 PHR, or about 10 PHR. In an embodiment, the antioxidant can be present in the nonwoven web in an amount ranging from about 2 to about 7 PHR.

[0089] In embodiments, the antioxidant can be provided in or on the fibers, in or on the nonwoven web, or both. In embodiments, the antioxidant can be coated on the fibers, coated on the nonwoven web, or both. In embodiments, the antioxidant can be dispersed throughout the nonwoven web. The antioxidant can be adsorbed to the fibers throughout the nonwoven web or bound by electrostatic forces. For example, the antioxidant can be added as the fibers are being laid so that the acid scavenger is provided throughout the nonwoven web. In embodiments, the antioxidant can be provided to the fiber-forming material during processing so that the acid scavenger is provided to the fibers themselves.

[0090] In an embodiment, the water-soluble nonwoven web may further comprise a filler, for example, a filler selected from the group consisting of high amylose starch, amorphous silica, hydroxyethylated starch, and combinations thereof. The filler may be provided in or on the fibers, in or on the nonwoven web, or both, as described herein for the acid scavengers and antioxidants. In an embodiment, the filler may be coated on the fibers, coated on the nonwoven web, or both. In an embodiment, the filler may be dispersed throughout the nonwoven web. The filler may be adsorbed to the fibers throughout the nonwoven web or may be attached by electrostatic forces. In an embodiment, the filler may be provided in the fiber-forming material.

[0091] The plurality of water-soluble fibers can be prepared by any process known in the art, such as wet chill gel spinning, thermoplastic fiber spinning, meltblowing, spunbonding, electrospinning, rotary spinning, continuous filament producing operations, tow fiber producing operations, and combinations thereof. In an embodiment, the fibers comprise water-soluble fibers prepared by wet chill gel spinning, meltblowing, spunbonding, or combinations thereof. In an embodiment, the fibers comprise water-soluble fibers prepared by wet chill gel spinning and are carded into a nonwoven web.

[0092] It is standard in the art to refer to fibers and nonwoven webs by the process used to prepare them. Thus, any reference herein to, for example, "meltblown fibers" or "carded nonwoven webs" should be understood to be merely identifying a particular fiber or web, rather than a product-by-process limitation to a particular meltblown or carding method. Thus, the processing terminology may be used to distinguish between fibers and / or nonwovens without limiting the listed fibers and / or nonwovens to preparation by any particular process.

[0093] The fibers of the present disclosure can be bicomponent fibers. As used herein, unless otherwise specified, "bicomponent fibers" refers not to fibers that contain a blend of fiber-forming materials, but rather to fibers that contain two or more distinct regions of fiber-forming materials, with the composition of the fiber-forming materials differing from region to region. Examples of bicomponent fibers include, but are not limited to, core / sheath bicomponent fibers, islands-in-the-sea bicomponent fibers, and side-by-side bicomponent fibers. Core / sheath bicomponent fibers generally include a core having 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 having 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). Islands-in-the-sea bicomponent fibers generally include a first continuous "sea" region having a fiber-forming material of a first composition and distinct "island" regions having fiber-forming materials of a second composition dispersed therein that are different from the first composition. Side-by-side bicomponent fibers generally include a first region extending along the length of the fiber that includes fiber-forming material of a first composition, and a second region extending along the length of the fiber that includes fiber-forming material of a second composition different from the first composition, the first region being adjacent to at least the second region. Such bicomponent fibers are well known in the art.

[0094] The shape of the fibers is not particularly limited, but can have a cross-sectional shape including, but not limited to, circular, elliptical (also referred to as ribbon), triangular (also referred to as delta), trilobal, and / or other multilobal shapes (FIG. 1). It will be understood that the shape of the fibers need not be perfectly geometric, e.g., a fiber having a circular cross-sectional shape need not have a perfect circle as a cross-sectional area, and a fiber having a triangular cross-sectional shape will generally have rounded corners. Without intending to be bound by theory, it is believed that wicking fibers in a nonwoven fabric (e.g., trilobal fibers) having a shape that provides capillary or groove-type directional flow paths for liquid can promote capillary action / wicking of liquid from the surface of the nonwoven fabric, providing improved liquid acquisition compared to the same nonwoven fabric having a fiber shape that does not include capillary or groove-type directional flow paths.

[0095] It will be understood that the diameter of a fiber refers to the cross-sectional diameter of the fiber along its 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 for the particular fiber type referred to, i.e., that a plurality of fibers prepared from a polyvinyl alcohol fiber-forming material have an arithmetic mean fiber diameter among the plurality of fibers. For shapes that are not typically considered to have a "diameter", such as triangular or multi-lobal shapes, the diameter refers to the diameter of a circle circumscribing the fiber shape (Figure 1).

[0096] The fibers of the present disclosure typically have a diameter in the range of about 10 microns to 300 microns, for example, 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 up to about 300 microns, up to about 275 microns, up to about 250 microns, up to about 225 microns, up to about 200 microns, up to about 100 microns, up to about 50 microns, up to about 45 microns, up to about 40 microns, or up to about 35 microns, for example, from about 10 microns to about 300 microns, from about 50 microns to about 300 microns, from about 100 microns to about 300 microns, from about 10 microns to about 50 microns, from about 10 microns to about 45 microns, or from about 10 microns to about 40 microns. In an embodiment, the water-soluble fibers used to prepare the water-dispersible nonwoven web of the present disclosure can have a diameter of more than 100 microns to about 300 microns. In an embodiment, the fibers comprise cellulose having a diameter ranging from 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 fibers comprise a water-soluble fiber-forming material and have a diameter ranging from 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 the water-soluble fibers used to prepare the water-dispersible nonwoven web of the present disclosure has a substantially uniform diameter. As used herein, a fiber diameter is "substantially uniform" if the variance in diameter among the fibers is less than 10%, e.g., 8% or less, 5% or less, 2% or less, or 1% or less. Fibers having a substantially uniform diameter can be prepared by the wet chill gel spinning process or thermoplastic fiber spinning, as described herein. Additionally, when a blend of fibers is used, the average fiber diameter can be determined using a weighted average of the individual fibers.

[0097] The fibers of the present disclosure used to prepare the nonwoven webs and nonwoven composite articles of the present disclosure can generally be of any length. In embodiments, the length of the fibers 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 up to about 100 mm, up to about 95 mm, up to about 90 mm, up to about 80 mm, up to about 70 mm, or up to about 60 mm. In embodiments, the length of the water-soluble fibers can be less than about 30 mm, or in the range of about 0.25 mm to less than about 30 mm, for example, at least about 0.25 mm, at least about 0.5 mm, at least about 0.75 mm, at least about 1 mm, at least about 2.5 mm, at least about 5 mm, at least about 7.5 mm, or at least about 10 mm, and up to about 29 mm, up to about 28 mm, up to about 27 mm, up to about 26 mm, up to about 25 mm, up to about 20 mm, or up to about 15 mm. The fibers can be prepared to any length by cutting and / or crimping the extruded polymer mixture. In embodiments, the fibers can be continuous filaments prepared by processes such as, for example, spunbonding, meltblowing, electrospinning, and rotary spinning, and the continuous filaments can be prepared and provided directly in web form. Additionally, when a blend of fibers is used, the average length of the fibers can be determined using a weighted average of the individual fibers.

[0098] Fibers of the present disclosure can generally have any length to diameter ratio. In embodiments, the length to diameter ratio of a fiber can 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.

[0099] The water-soluble fibers used to prepare the water-soluble nonwoven web of the present disclosure can generally have any tenacity. The tenacity of the fiber correlates with the coarseness of the fiber. As the tenacity of the fiber decreases, the coarseness of the fiber increases. The fibers used to prepare the water-soluble nonwoven web of the present disclosure can have a tenacity of 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 3 to about 8 cN / dtex, or about 4 to about 8 cN / dtex. dtex, or about 6 to about 8 cN / dtex, or about 4 to about 7 cN / dtex, or about 10 to about 20, or about 10 to about 18, or about 10 to about 16, or about 1 cN / dtex, about 2 cN / dtex, about 3 cN / dtex, about 4 cN / dtex, about 5 cN / dtex, about 6 cN / dtex, about 7 cN / dtex, about 8 cN / dtex, about 9 cN / dtex, about 10 cN / dtex, about 11 cN / dtex, about 12 cN / dtex, about 13 cN / dtex, about 14 cN / dtex, or about 15 cN / dtex. In an embodiment, the fiber can have a toughness of about 3 cN / dtex to about 10 cN / dtex. In an embodiment, the fiber can have a toughness of about 5 cN / dtex to about 10 cN / dtex. In embodiments, the fibers may have a tenacity of about 7 cN / dtex to about 10 cN / dtex. In embodiments, the fibers may have a tenacity of about 4 cN / dtex to about 8 cN / dtex. In embodiments, the fibers may have a tenacity of about 6 cN / dtex to about 8 cN / dtex.

[0100] The fibers used to prepare the water-soluble nonwoven webs of the present disclosure can generally have any fineness. Fiber fineness correlates to how many fibers are present in a cross-section of a yarn of a given thickness. Fiber fineness is the ratio of the mass of the fiber to its length. The main physical unit of fiber fineness is 1 tex, which is equal to 1000m of fiber weighing 1g. Typically, the unit dtex is used, which represents 1g / 10,000m of fiber. The fiber fineness can be selected to provide a nonwoven web with suitable nonwoven web stiffness / hand, torsional stiffness, reflection and interaction with light, absorption of dyes and / or other actives / additives, ease of fiber spinning in the manufacturing process, and uniformity of the finished product. Generally, as the fiber fineness increases, the nonwoven fabric obtained therefrom exhibits higher uniformity, improved tensile strength, elongation, and luster. In addition, without intending to be bound by theory, it is believed that finer fibers result in slower dissolution times compared to larger fibers based on density. Further, without intending to be bound by theory, when a blend of fibers is used, the average fiber fineness can be determined using a weighted average of the 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 webs of the present disclosure can include fibers that are very fine, fine, medium, slightly coarse, or combinations 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. In an embodiment, the fibers include fibers having a fineness of about 1.7 dtex and fibers having a fineness of about 2.2 dtex.

[0101] Wet-cooled gel spinning

[0102] In an embodiment, the plurality of water soluble fibers comprises water soluble fibers prepared by a wet cryogel spinning process, the wet cryogel spinning process comprising: (a) dissolving a water-soluble polymer(s) in a solution to form a polymer mixture, the polymer mixture optionally including an auxiliary; (b) extruding the polymer mixture through a spinning nozzle into a coagulation bath to form an extruded polymer mixture; (c) passing the extruded polymer mixture through a solvent exchange bath; (d) optionally wet-stretching the extruded polymer mixture; and (e) finishing the extruded polymer mixture to provide water soluble fibers. Includes.

[0103] The solvent for dissolving the water-soluble polymer may suitably be any solvent that the water-soluble polymer dissolves in. In an embodiment, the solvent for dissolving the water-soluble polymer comprises a polar aprotic solvent. In an embodiment, the solvent for dissolving the water-soluble polymer comprises dimethyl sulfoxide (DMSO).

[0104] Typically, the coagulation bath contains a chilled 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 contain a mixture of a solvent in which the polymer is soluble and a solvent in which the polymer is not soluble. The solvent in which the polymer is not soluble is typically the predominant solvent, and the solvent in which the polymer is not soluble comprises more than 50% of the mixture.

[0105] After passing through the coagulation bath, the extruded polymer mixture gel can be passed through one or more solvent exchange baths. The solvent exchange baths are provided to exchange the solvent in which the water-soluble polymer dissolves with a solvent in which the water-soluble polymer does not dissolve to further coagulate the extruded polymer mixture, and to exchange the solvent in which the water-soluble polymer dissolves with a solvent that evaporates more easily, thereby reducing drying time. The solvent exchange baths can include a series of solvent exchange baths with a gradient of solvents in which the water-soluble polymer dissolves and solvents in which the water-soluble polymer does not dissolve, a series of solvent exchange baths with only solvents in which the water-soluble polymer does not dissolve, or a single solvent exchange bath with only solvents in which the water-soluble polymer does not dissolve. In an embodiment, at least one solvent exchange bath can consist essentially of a solvent in which the water-soluble polymer does not dissolve.

[0106] Finished fibers are sometimes referred to as staple fibers, short cut fibers, or pulp. In an embodiment, finishing includes drying the extruded polymer mixture. In an embodiment, finishing includes cutting or crimping the extruded polymer mixture to form individual fibers. Wet drawing of the extruded polymer mixture provides the extruded polymer mixture with a substantially uniform diameter from which fibers are cut. Drawing is distinct from extrusion, as is well known in the art. In particular, extrusion refers to the act of making fibers by forcing a resin mixture through a spinneret head, while drawing refers to mechanically pulling the fibers in the machine direction to promote polymer chain orientation and crystallinity in order to increase the strength and toughness of the fibers.

[0107] In embodiments in which the water soluble fibers are prepared from a wet cryogel spinning process, the water soluble polymer can generally be any water soluble polymer or blend thereof, e.g., two or more different polymers, as generally described herein. In a refinement of the foregoing embodiment, the polymer(s) can have a molecular weight in the range of, for example, 10 to 10,000,000, e.g., 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 10,000,000, up to 5,000,000, up to 2,500,000, up to 1,000,000, up to 900,000, up to 750,000, up to 500,000, up to 250,000, up to 100,000, up to 90,000, up to 75,000, The degree of polymerization (DP) may be any value ranging from 0, up to 50,000, up to 25,000, up to 12,000, up to 10,000, up to 5,000, or up to 2,500, for example, 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 an embodiment, the DP is at least 1,000. The aids can be added to the fibers themselves, or to the nonwoven web during the carding and / or bonding process, as described above.

[0108] Thermoplastic Fiber Spinning

[0109] Thermoplastic fiber spinning is well known in the art. Briefly, thermoplastic fiber spinning is (a) preparing a polymer mixture comprising a fiber-forming polymer and, optionally, co-agents; (b) extruding the polymer mixture through a spinneret nozzle to form an extruded polymer mixture; (c) optionally stretching the extruded polymer mixture; and (d) finishing the extruded polymer mixture to provide fibers. Includes.

[0110] Finishing of the Thermoplastic Fiber Spinning Process Staple fibers can be finished by drying, cutting and / or crimping to form individual fibers. Drawing of an extruded polymer mixture mechanically pulls the fiber in the machine direction to promote polymer chain orientation and crystallinity to increase fiber strength and toughness. The step of preparing a polymer mixture for thermoplastic fiber spinning typically includes (a) preparing a solution of fiber-forming materials and a readily volatile solvent such that after the solution is extruded through a spinneret, the solvent readily evaporates when the solution is contacted with a stream of hot air, leaving behind a solid fiber, or (b) melting the polymer such that after the hot polymer is extruded through a spinneret, the polymer is solidified by quenching with cold air. Thermoplastic fiber spinning processes differ from wet chill gel spinning processes at least in that (a) in thermoplastic fiber spinning processes, the extruded fiber is solidified by evaporation of a solvent or by quenching the hot solid fiber with cold air rather than by the use of a coagulation bath, and (b) in wet chill gel spinning processes, drawing, if necessary, is performed while the fiber is in a gel state rather than a solid state.

[0111] The fiber-forming material for preparing fibers from the thermoplastic fiber spinning process can generally be any fiber-forming polymer or blend thereof, for example, two or more different polymers, provided that the polymer or blend thereof has suitable solubility in a readily volatile solvent and / or has a melting point lower than and different from its decomposition temperature. Furthermore, when using a blend of fiber-forming polymers to make fibers, the fiber-forming material must have similar solubility in a readily volatile solvent and / or have a similar thermal profile, such that the two or more fiber-forming materials melt at similar temperatures. In contrast, the fiber-forming material for preparing fibers from the wet-cooled gel spinning process is not limited in the same way, and fibers can be prepared from any blend of two or more polymers that dissolve in the same solvent system, and the solvent system does not need to be a single solvent or even a volatile solvent.

[0112] The fiber-forming polymer(s) for preparing thermoplastic fiber spun fibers can have a degree of polymerization (DP) in the range of, for example, 10 to 10,000, e.g., 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.

[0113] Melt Spinning

[0114] Melt spinning is well known in the art and is understood to refer to both spunbond and meltblown processes. Melt spinning is a continuous process that directly prepares nonwoven webs in series with fiber formation. As mentioned above, melt spinning forming fibers are not finished or cut to any consistent length (e.g., staple fibers are not prepared by these processes). In addition, melt spinning does not include a drawing step, so the only control on the diameter of the resulting melt spun fibers is the size of the hole that extrudes the fiber forming material, and the polymer chains are typically not oriented in any particular direction.

[0115] Briefly, melt spinning involves: (a) preparing a polymer mixture comprising a fiber-forming polymer and, optionally, co-agents; (b) extruding the polymer mixture through a die assembly to form an extruded polymer mixture; (c) quenching the extruded polymer mixture; (d) depositing the quenched extruded polymer mixture onto a belt to form a nonwoven web; and (e) bonding the nonwoven web Includes.

[0116] In the spunbond process, the extruded polymer mixture is pumped into a die assembly as a molten polymer and is quenched by cold air as it passes through the die assembly. In the meltblown process, the extruded polymer mixture is pumped into a die assembly through which hot air is blown and is quenched as it exits the die assembly and comes into contact with air at ambient temperature. In both processes, the fibers are continuously dropped onto a belt or drum and are usually propelled by pulling a vacuum underneath the belt or drum.

[0117] The diameter of the melt spun fibers generally ranges from about 0.1 to about 50 microns, e.g., at least about 0.1 micron, 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 5 ... about 30 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. Although meltblown processes can provide ultrafine fibers having an average diameter in the range of about 1 to 10 microns, it is well known in the art that meltblown processes have a very large variation in fiber-to-fiber diameter, for example, a variation of 100 to 300%. Additionally, it is well known in the art that spunbond fibers may have larger average fiber diameters, e.g., typically from about 15 to about 25 microns, but have improved uniformity among fibers, e.g., about 10% variation.

[0118] The fiber-forming materials for heated extrusion processes (e.g., melt spinning, thermoplastic fiber spinning) are more limited than those for wet-cooled gel spinning processes. Generally, the degree of polymerization for heated extrusion processes is limited to a range of about 200 to about 500. When the degree of polymerization falls below 200, the viscosity of the fiber-forming material is too low, and the individual fibers prepared by pumping the material through the die assembly do not maintain proper separation after exiting the die assembly. Similarly, when the degree of polymerization rises above 500, the viscosity is too high to efficiently pump the material through sufficiently small holes in the die assembly to perform the process at high speeds, thus resulting in loss of process efficiency and uniformity of the fibers and / or nonwovens. Furthermore, processes requiring heating of the fiber-forming material are not suitable for polyvinyl alcohol homopolymers, as they generally do not have the required thermal stability.

[0119] The wet chill gel spinning process advantageously provides one or more benefits, such as providing fibers containing a blend of water-soluble polymers, providing control of fiber diameter, providing relatively large diameter fibers, providing control of fiber length, providing control of fiber tenacity, providing high tenacity fibers, providing fibers from polymers with a large degree of polymerization, and / or providing fibers that can be used to provide a self-supporting nonwoven web. Continuous processes such as spunbonding, meltblown, electrospinning, and rotary spinning generally do not allow blending of water-soluble polymers (e.g., due to the difficulty in matching the melt index of various polymers), forming large diameter fibers (e.g., greater than 50 microns), controlling fiber length, providing high tenacity fibers, and using polymers with a high degree of polymerization. Furthermore, the wet chill gel spinning process advantageously is not limited to polymers that are only melt-processable, and therefore can utilize fibers made from fiber-forming materials with very high molecular weights, high melting points, low melt flow indexes, or combinations thereof, providing fibers with stronger physical properties and different chemical functionality compared to fibers prepared by heated extrusion processes. Furthermore, advantageously, the wet cryogel spinning process is not limited by the viscosity of the polymer. In contrast, it is known in the art that processes that require melting of the fiber-forming material are limited to fiber-forming materials with a viscosity of 5 cP or less. Thus, fibers that include polymers with a viscosity of more than 5 cP, including polyvinyl alcohol homopolymers and copolymers, can only be utilized by wet cryogel spinning.

[0120] Nonwoven Web

[0121] The nonwoven web of the present disclosure is generally a sheet-like structure with two outer surfaces, and the nonwoven web comprises a plurality of fibers.The nonwoven web of the present disclosure can be prepared from fibers using any method known in the art.As known in the art, when the fibers are spunbonded or meltblown, the fibers are laid continuously to form a nonwoven web, and then the fibers are bonded.

[0122] Staple fibers can also be carded or airlaid and bonded to provide a nonwoven web. Carding and airlaying methods are well known in the art.

[0123] Methods for bonding nonwoven webs are well known in the art. In general, bonding can include thermal, mechanical, and / or chemical bonding. Thermal bonding can include, but is not limited to, calendaring, embossing, air-through, and ultrasonic. Mechanical bonding can include, but is not limited to, hydroentanglement (spunlace), needle punch, and stitch bond. Chemical bonding can include, but is not limited to, solvent bonding and resin bonding.

[0124] Thermal bonding is accomplished by applying heat and pressure, typically maintaining the pore size, shape, and arrangement created by the carding process. Thermal bonding conditions can be readily determined by one skilled in the art. In general, if too little heat and / or pressure is applied, the fibers will not bond sufficiently to form a self-supporting web, and if too much heat and / or pressure is applied, the fibers will begin to fuse together. The chemistry of the fiber dictates the upper and lower limits of heat and / or pressure for thermal bonding. While not intending to be bound by theory, it is believed that at temperatures above 235°C, polyvinyl alcohol-based fibers decompose. Methods of embossing for thermal bonding of fibers are known. Embossing can be single-sided or double-sided embossing. Typically, embossing of water-soluble fibers involves single-sided embossing using a single embossing roll consisting of a regular circular array and a steel roll with a flat surface. As embossing increases (e.g., as surface features are imparted to the web), the surface area of ​​the web increases. Without intending to be bound by theory, it is expected that as the surface area of ​​the web increases, the solubility of the web increases. Thus, the dissolution properties of a nonwoven web can be advantageously tailored by varying the surface area through embossing.

[0125] Through-air bonding generally requires a high thermoplastic resin content in the nonwoven web and two different melting point materials. In through-air bonding, an unbonded nonwoven web is circularly moved around a drum while hot air flows from the outside of the drum toward the center of the drum. Through-air bonding is suitable for low density and higher basis weight (e.g., 20 g / m 2 Super ~ about 2000g / m 2 ). Nonwoven fabrics bonded by air bonding are typically very soft.

[0126] Chemical bonding generally includes solvent bonding and resin bonding. In particular, chemical bonding typically uses a binder solution of a solvent and resin (e.g., latex, or waste polymers left over from fiber preparation). The nonwoven fabric can be coated with the binder solution and heat and pressure applied to cure the binder and bond the nonwoven fabric. The binder solution can be applied by immersing the nonwoven fabric in a bath of binder solution, spraying the binder solution onto the nonwoven fabric, extruding the binder solution onto the web (foam bonding), and / or applying the binder solution as a print or gravure.

[0127] Chemical bonding may result in smaller, less regular pores than carded / melt spun pores. Without intending to be bound by theory, it is believed that if the resin solution used for chemical bonding is concentrated enough and / or sufficient pressure is applied, a non-porous water-dispersible nonwoven web can be formed. The solvent used in chemical bonding induces partial solubilization of the fibers present in the web to weld and bond the fibers together. Thus, in general, the solvent for chemical bonding can be any solvent that can at least partially solubilize one or more fiber-forming materials of the fibers of the nonwoven. In an embodiment, the solvent is selected from the group consisting of water, ethanol, methanol, DMSO, glycerin, and combinations thereof. In an embodiment, the solvent is selected from the group consisting of water, glycerin, and combinations thereof. In an embodiment, the binder solution comprises a solvent selected from the group consisting of water, ethanol, methanol, DMSO, glycerin, and combinations thereof, and further comprises a resin selected from the group consisting of polyvinyl alcohol, latex, and polyvinylpyrrolidone. The binder provided in the solution aids in the welding process to provide a more mechanically robust web. The temperature of the polymer solution is not particularly limited and can be provided at room temperature (about 23° C.).

[0128] In some embodiments, a second layer of fibers can be used to bond the nonwoven web. In an embodiment, at least one nonwoven layer of the composite article of the present disclosure is bonded using a second layer of nonwoven web / fibers. In an embodiment, at least two nonwoven layers of the composite article of the present disclosure are bonded using an additional layer of nonwoven web / fibers. In an embodiment, at least one nonwoven layer of the composite article of the present disclosure is bonded using thermal, mechanical, or chemical bonding alone or in addition to bonding using an additional layer of nonwoven web / fibers.

[0129] Pore ​​size can be determined using high magnification and systematic surface analysis techniques, including, but not limited to, Brunauer-Emmett-Teller theory (BET), small angle X-ray scattering (SAXS), and molecular adsorption.

[0130] Nonwoven webs can be characterized by their basis weight. The basis weight of a nonwoven is the mass per unit area of ​​the nonwoven. The basis weight can be modified by changing the manufacturing conditions, as is known in the art. The nonwoven web can have the same basis weight before and after bonding. Alternatively, the bonding method can change the basis weight of the nonwoven web. For example, when bonding occurs through the application of heat and pressure, the thickness of the nonwoven (and therefore the area of ​​the nonwoven) can decrease, thereby increasing the basis weight. Thus, as used herein, unless otherwise specified, the basis weight of a nonwoven refers to the basis weight of the nonwoven after bonding.

[0131] The nonwoven webs of the present disclosure generally have a mass of 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 / m2 , 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 25 g / m 2 ~about 70g / m 2 The sheet may have any basis weight in the range of 1000 to 15000 grammage.

[0132] The nonwoven fabric web of the present disclosure can generally have any thickness. Suitable thicknesses include, but are 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, about 40 to about 90 μm, about 50 to 80 μm, or about 60 to 65 μm, for example, 50 μm, 65 μm, 76 μm, or 88 μm.

[0133] The nonwoven webs of the present disclosure can be characterized as high loft or low loft. Loft generally refers to the ratio of thickness to mass per unit area (i.e., basis weight). High loft nonwoven webs can be characterized by a high ratio of thickness to mass per unit area. As used herein, "high loft" refers to nonwoven webs of the present disclosure having a basis weight as defined herein and a thickness greater than 200 μm. The thickness of the nonwoven web can be determined according to ASTM D5729-97, ASTM D5736, and ISO 9073-2:1995, and can include, for example, subjecting the nonwoven web to a load of 2N and measuring the thickness. High loft materials can be used, for example, for through-air bonding, or cross-wrapping, according to methods known in the art, where a non-bonded web is folded over itself using a cross-wrapper to increase loft and basis weight. While not intending to be bound by theory, it is believed that the solubility of nonwoven webs is not dependent on the thickness of the web, in contrast to water-soluble nonwoven webs, where the solubility of the nonwoven web may depend on the thickness of the nonwoven web. In this regard, it is believed that the parameter that limits the access of water to the fibers, and ultimately the dissolution of the fibers, is the basis weight (i.e., fiber density in the nonwoven), since individual fibers provide a greater surface area than water-soluble films, independent of the thickness of the nonwoven web.

[0134] The solubility of the water-soluble nonwoven web of the present disclosure is generally a function of the type of fiber used to prepare the web and the basis weight of the water-soluble web. Without intending to be bound by theory, it is believed that the solubility profile of the nonwoven web follows the same solubility profile of the fiber used to prepare the nonwoven web, and the solubility profile of the fiber generally follows the same solubility profile of the polymer from which the fiber is prepared. For example, for a nonwoven web containing PVOH fibers, the degree of hydrolysis of the PVOH polymer can be selected, which in turn affects the water solubility of the nonwoven web. In general, at a given temperature, as the degree of hydrolysis of the PVOH polymer increases from partial hydrolysis (88% DH) to full hydrolysis (≧98% DH), the water solubility of the polymer generally decreases. Thus, in one option, the water-soluble nonwoven web can be cold water soluble. For copoly(vinyl acetate vinyl alcohol) polymers that do not contain any other monomers (e.g., not copolymerized with anionic monomers), a cold water-soluble web that dissolves in water at a temperature below 10°C can include fibers of PVOH 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 alternative, the water-soluble nonwoven web can be hot water-soluble. For copoly(vinyl acetate vinyl alcohol) polymers that do not contain any other monomers (e.g., not copolymerized with anionic monomers), a hot water-soluble web that dissolves in water at a temperature of at least about 60°C can include fibers of PVOH having a degree of hydrolysis of at least about 98%.

[0135] Modification of PVOH generally increases the solubility of the PVOH polymer. Therefore, at a given temperature, the solubility of a water-soluble nonwoven web prepared from a PVOH copolymer is expected to be higher than that of a nonwoven web prepared from a PVOH homopolymer having the same degree of hydrolysis as the PVOH copolymer. According to these trends, water-soluble nonwoven webs with specific solubility characteristics can be designed by blending polymers into fibers and / or fibers into nonwoven webs.

[0136] Furthermore, if the fiber composition remains constant, as the basis weight of the web increases, the rate of dissolution of the web decreases because there is more material to dissolve. For example, at a given temperature, a 40 g / m2 web made from fibers containing PVOH polymers will dissolve at a rate of 100 g / m2. 2 A water-soluble web having a basis weight of, for example, 30 g / m 2 The basis weight can also be used to modify the solubility characteristics of a water-soluble nonwoven web. Water-soluble nonwoven webs generally have a basis weight of 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 10g / 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 , about 25g / m 2 ~about 70g / m 2 , or about 40 g / m 2~about 60g / m 2 The sheet may have any basis weight in the range of 1000 to 15000 grammage.

[0137] Without intending to be bound by theory, it is believed that the solubility (in terms of time to complete dissolution) of a water-soluble nonwoven web is expected to surpass that of a water-soluble film of the same size (L×W) and / or mass prepared from the same PVOH polymer. This is due to the larger surface area found in the nonwoven compared to the film, resulting in faster solubilization. As shown in the examples below, a nonwoven web prepared from a PVOH homopolymer with a degree of hydrolysis of 88% dissolves in 14 seconds, while a water-soluble film of similar size prepared from the same PVOH homopolymer with a degree of hydrolysis of 88% dissolves in about 100 seconds.

[0138] The tenacity of the water-soluble nonwoven web may be the same as or different from the tenacity of the fibers used to prepare the web. Without intending to be bound by theory, it is believed that the tenacity of the nonwoven web is related to the strength of the nonwoven web, with a higher tenacity providing the nonwoven web with a higher strength. In general, the tenacity of the nonwoven web can be modified by using fibers with different tenacities. The tenacity of the nonwoven web can also be affected by processing. In general, the water-soluble web of the present disclosure has a relatively high tenacity, i.e., the water-soluble nonwoven web is a self-supporting web that can be used as the sole material to prepare an article and / or pouch. In contrast, nonwoven webs prepared by meltblown, electrospinning, and / or rotary spinning processes typically have a low tenacity and may not be self-supporting or may not be used as the sole web to form an article or pouch.

[0139] In general, the coefficient of kinetic friction and the ratio of the coefficient of static friction to the coefficient of kinetic friction for the water-soluble nonwoven web of the present disclosure are lower than the coefficient of kinetic friction and the ratio of the coefficient of static friction to the coefficient of kinetic friction for the water-soluble film due to the increased surface roughness of the nonwoven web relative to the water-soluble film, which reduces surface contact to the nonwoven web. Advantageously, this surface roughness can provide consumers with improved feel (i.e., cloth-like hand instead of rubber-like hand), improved aesthetics (i.e., less gloss than water-soluble films), and / or promote processability in the preparation of thermoformed and / or vertically formed, filled and sealed and / or multi-chambered packets that require the web to be stretched along the surface of a processing machine / mold. Thus, the fibers should not be so rough as to cause drag, but should be rough enough to provide surface roughness to the resulting nonwoven web.

[0140] The water-soluble nonwoven web of the present disclosure can be used as a single layer, can be layered with other water-soluble nonwoven webs, or can be in the form of a laminate with a water-soluble film. In some embodiments, the water-soluble nonwoven web comprises a single layer of water-soluble nonwoven web. In some embodiments, the water-soluble nonwoven web is a multi-layer water-soluble nonwoven web comprising two or more layers of water-soluble nonwoven web. One or more layers can be laminated together. In a refinement of the above embodiment, the two or more layers can be the same (e.g., prepared from the same fibers and have the same basis weight). In a refinement of the above embodiment, the two or more layers can be different (e.g., prepared from different types of fibers and / or have different basis weights).

[0141] Generally, a multi-layer water-soluble nonwoven web can have a basis weight that is the sum of the basis weights of the individual layers, and therefore the multi-layer water-soluble nonwoven web will take longer to dissolve than either of the individual layers provided as a single layer.

[0142] In embodiments, the water soluble nonwoven webs of the present disclosure have a disintegration time of not more than 300 seconds according to MSTM 205 in water at 23° C. after 6 or 8 weeks of exposure to TCCA, SBS, or calcium hypochlorite compositions at 38° C. and 80% RH atmosphere.

[0143] In embodiments, after 6 or 8 weeks of exposure to a TCCA, SBS, or calcium hypochlorite composition at 38° C. and 80% RH atmosphere, the surface area of ​​the nonwoven web residue after testing according to MSTM 205 in water at 23° C. is less than about 50% of the surface area of ​​the nonwoven web before testing according to MSTM 205.

[0144] In embodiments, the nonwoven web has a b value of not greater than 3.5, or not greater than 3.0, or not greater than 2.5 after 6 or 8 weeks of exposure to a TCCA, SBS, or calcium hypochlorite composition at 38° C. and 80% RH atmosphere. * In an embodiment, the nonwoven web maintains a b value of not more than 3.5 after 6 or 8 weeks of exposure to a TCCA, SBS, or calcium hypochlorite composition at 38° C. and 80% RH atmosphere. * In an embodiment, the nonwoven web maintains a b value not exceeding 3.0 after 6 or 8 weeks of exposure to a TCCA, SBS, or calcium hypochlorite composition at 38° C. and 80% RH atmosphere. * In an embodiment, the nonwoven web maintains a b value of not more than 2.5 after 6 or 8 weeks of exposure to a TCCA, SBS, or calcium hypochlorite composition at 38° C. and 80% RH atmosphere. * Maintain the value.

[0145] Further provided herein is a water-soluble unit dose article comprising a water-soluble nonwoven web as described herein in the form of a packet comprising an outer wall having an outer surface and an inner surface defining an inner pouch volume, and a composition contained in the inner pouch volume. In an embodiment, the composition can comprise an irritating chemical. In an embodiment, the irritating chemical can comprise an acid, an oxidizing agent, a base, or a combination thereof. In an embodiment, the irritating chemical can comprise an acid. In an embodiment, the irritating chemical can comprise an oxidizing agent. In an embodiment, the irritating chemical can comprise a base.

[0146] Also provided herein is a unit dose article comprising a packet including an outer wall, the outer wall having an exterior surface and an interior surface defining an inner pouch volume, the outer wall comprising a nonwoven web including a plurality of fibers including a sulfonate-modified PVOH fiber-forming material including sulfonated anionic monomer units, the sulfonate-modified PVOH fiber-forming material having a degree of hydrolysis of at least 95%, the sulfonated anionic monomer being present in an amount ranging from about 1 mol% to about 5 mol%, and a composition contained in the inner pouch volume. In an embodiment, the composition can include an irritating chemical. In an embodiment, the irritating chemical can include an oxidizing agent, a base, or a combination thereof. In an embodiment, the irritating chemical can include an oxidizing agent. In an embodiment, the oxidizing agent is a base-mediated oxidizing agent. In an embodiment, the base-mediated oxidizing agent can include calcium hypochlorite.

[0147] Also provided herein is a unit dose article comprising a packet including an outer wall, the outer wall having an exterior surface and an interior surface defining an inner pouch volume, the outer wall comprising a nonwoven web including a plurality of fibers including (i) polyvinylpyrrolidone, and (ii) sulfonate-modified polyvinyl alcohol (PVOH), carboxyl-modified PVOH, or both, and a composition contained in the inner pouch volume. In an embodiment, the composition can include an irritating chemical. In an embodiment, the irritating chemical can include an acid, an oxidizing agent, a base, or a combination thereof. In an embodiment, the irritating chemical can include an acid. In an embodiment, the irritating chemical can include an oxidizing agent. In an embodiment, the irritating chemical can include a base.

[0148] In embodiments, the irritant chemical can include one or more of hypochlorite, hypochlorous acid, halogenated isocyanurates, chlorates, chlorites, perchlorates, bromates, perbromates, halogenated hydantoins, perborates, periodates, persulfates, permanganates, chromates, dichromates, nitrates, nitrites, peroxides, ketone peroxides, peroxyacids, citric acid, hydrochloric acid, and inorganic acids, such as one or more of sodium bisulfate (SBS), cyanuric acid, dichloroisocyanuric acid, trichloroisocyanuric acid (TCCA), and calcium hypochlorite. In embodiments, the composition can be both an acid and an oxidant, such as trichloroisocyanuric acid. In embodiments, the irritant chemical can include hypochlorite. In embodiments, the irritant chemical can include calcium hypochlorite.

[0149] In an embodiment, the irritating chemical can include a chlorine-releasing compound. In an embodiment, an acid, an oxidizing agent, a base, or a combination thereof can include a chlorine-releasing compound. As used herein, the term "chlorine-releasing compound" refers to a family of chemicals that release chlorine or chloride ions when in contact with water. Chlorine-releasing compounds are commonly used as bleaching materials, water disinfectants, medical equipment disinfectants, and other disinfection purposes.

[0150] In one embodiment, by way of example, the oxidizing agent may include hypochlorous acid, hypochlorite, halogenated isocyanurates, such as sodium dichloroisocyanurate, chlorate, chlorite, perchlorate, bromate, perbromate, halogenated hydantoins, perborates, periodates, persulfates, permanganates, chromates, dichromates, nitrates, nitrites, peroxides, ketone peroxides, peroxyacids, inorganic acids, or combinations thereof. In an embodiment, the oxidizing agent includes trichloroisocyanuric acid. In an embodiment, the oxidizing agent may include trichloroisocyanuric acid (TCCA), dichloroisocyanuric acid (DCCA), 1-bromo-3-chloro-5,5-dimethylhydantoin (BCDMH), calcium hypochlorite (Cal-Hypo), potassium peroxymonosulfate (MPS). In an embodiment, the irritant chemical may include a base-mediated oxidizing agent. In an embodiment, the base-mediated oxidant can include hypochlorite. In an embodiment, the base-mediated oxidant can include calcium hypochlorite. In an embodiment, the irritant chemical can include an acid-mediated oxidant. As used herein, the term "acid-mediated oxidant" refers to an oxidant that oxidizes another chemical species using an acidic mechanism oxidation pathway, such as that shown in Scheme 2. In general, acid-mediated oxidants include any oxidizing compound that includes an acid-stabilizing molecule. In an embodiment, the acid-mediated oxidant can include TCCA, DCCA, BCDMH, or a combination thereof. In an embodiment, the acid-mediated oxidant can include a halogenated isocyanurate. In an embodiment, the acid-mediated oxidant can include TCCA, DCCA, or a combination thereof. In an embodiment, the acid-mediated oxidant can include BCDMH.

[0151] Scheme 2. Three acid-mediated oxidation pathways for PVOH. 1. Condensation reaction [ka] 2. Crosslinking [ka] 3. Oxidative ketogenesis [ka]

[0152] Advantageously, it has been found that the unit dose article disclosed herein can have unexpectedly selective resistance to base-mediated oxidants compared to acid-mediated oxidants.For example, nonwoven webs comprising fibers that constitute AMPS-modified PVOH nonwoven webs have shown very different results when exposed to TCCA (acid-mediated oxidants) or separately calcium hypochlorite (base-mediated oxidants) for 2, 4, and 6 weeks at 38°C and 80%RH atmosphere.Although TCCA and calcium hypochlorite are both oxidants, nonwoven webs comprising AMPS-modified PVOH perform well when exposed to calcium hypochlorite and do not perform as well when exposed to TCCA. In particular, when exposed to calcium hypochlorite for 6 weeks at 38° C. and 80% RH, the nonwoven web maintained acceptable disintegration (e.g., 100% disintegration in less than 300 seconds) according to the Dissolution, Disintegration, and % Residue Test (MSTM 205) and resisted discoloration (e.g., b less than 3) according to the CIELab Test. * values) and maintained acceptable percent elongation (e.g., less than 15%) by elongation testing. However, nonwoven fabrics having the same composition exhibited unacceptable disintegration (e.g., taking longer than 300 seconds to disintegrate) by MSTM 205 and unacceptable discoloration (e.g., greater than 3 b values) when exposed to TCCA for only 2 weeks at 38° C. and 80% RH atmosphere. * values) and even unacceptable % elongation (e.g., greater than 15%). Without intending to be bound by theory, it is believed that the different mechanistic pathways of each oxidant lead to the mixed results in performance.

[0153] In embodiments, the acid may include an acid having a pH ranging from -2 to 6.5 in a 1% solution, or from -1 to 6 in a 1% solution, or from 0 to 5 in a 1% solution, or from 1 to 5 in a 1% solution, or from 1 to 4 in a 1% solution. In embodiments, the acid may include sodium bisulfate, cyanuric acid, dichloroisocyanuric acid, trichloroisocyanuric acid, citric acid, hydrochloric acid, or combinations thereof. In embodiments, the acid may include sodium bisulfate, cyanuric acid, dichloroisocyanuric acid, trichloroisocyanuric acid, or combinations thereof.

[0154] In embodiments, the base may include sodium carbonate, sodium bicarbonate, or a combination thereof.

[0155] In an embodiment, the water-soluble unit dose article can include a non-domestic care composition. The non-domestic care composition can be selected from agricultural compositions, aviation compositions, food and nutritional compositions, industrial compositions, livestock compositions, marine compositions, medical compositions, commercial compositions, military and paramilitary compositions, office compositions, entertainment and park compositions, pet compositions, pool and / or water treatment compositions, and combinations thereof. In an embodiment, the non-domestic care composition is a pool and / or water treatment composition.

[0156] In embodiments, the water-soluble unit dose article may include an irritant chemical composition comprising a concentration of an acid, an oxidizer, a base, or a combination thereof in the range of 50% to 100% by weight, or 60% to 100% by weight, or 70% to 100% by weight, or 80% to 100% by weight, or 90% to 100% by weight, based on the total weight of the composition. In embodiments, the concentration of an acid, an oxidizer, a base, or a combination thereof in the non-household care composition of the water-soluble unit dose article is in the range of 50% to 100% by weight, or 60% to 100% by weight, or 70% to 100% by weight, or 80% to 100% by weight, or 90% to 100% by weight, based on the total weight of the non-household care composition.

[0157] In an embodiment, the packet may further include a first coating comprising an acid scavenger and / or an antioxidant, the first coating being in contact with the water-soluble nonwoven web. In an embodiment, the first coating comprising an acid scavenger, an antioxidant, or a combination thereof may be provided on at least a portion of the inner surface of the outer wall. In an embodiment, the first coating comprising an acid scavenger, an antioxidant, or a combination thereof may be provided on at least a portion of the outer surface of the outer wall. In an embodiment, the packet further includes a second coating comprising an acid scavenger, an antioxidant, or both. In an embodiment, the first coating is provided on at least a portion of the inner surface of the outer wall and the second coating is provided on at least a portion of the outer surface of the pouch.

[0158] The first and / or second coatings of the water-soluble unit dose articles described herein can be provided to the outer wall using any suitable method known in the art, for example, solution coating, such as spin coating, dip coating, brush coating, and spray coating.

[0159] The acid scavenger and / or antioxidant provided in the first and / or second coating can be any acid scavenger and / or antioxidant disclosed herein. In embodiments, the acid scavenger includes N-vinylpyrrolidone, sodium metabisulfite, zinc oxide, hydrotalcite, metal stearates, activated olefins, allyl-based compounds, carboxylate compounds, ethylene-containing compounds, quaternary ammonium compounds, tertiary amine-containing compounds, and combinations thereof. In embodiments, the antioxidant includes propyl gallate, gallic acid, phenolic compounds, hindered amines, sodium metabisulfite, zinc acetate, and combinations thereof.

[0160] There is further provided a water soluble unit dose article comprising a water soluble nonwoven web according to the present disclosure in the form of a packet having an outer wall having an outer surface and an inner surface defining an inner pouch volume, and a pool and / or water treatment composition contained in the inner pouch volume, wherein the concentration of the irritating chemical in the pool and / or water treatment composition is in the range of 50% to 100% by weight, and the packet optionally comprises a first coating comprising an acid scavenger provided on at least a portion of the inner surface of the outer wall.

[0161] In an embodiment, a unit dose article as disclosed herein comprising a plurality of fibers comprising a sulfonate-modified PVOH fiber-forming material comprising sulfonated anionic monomer units, wherein the sulfonate-modified PVOH fiber-forming material has a degree of hydrolysis of at least 95% and the sulfonated anionic monomer is present in an amount ranging from about 1 mol % to about 5 mol %, can comprise a pool and / or water treatment composition contained in an inner pouch volume, wherein the pool and / or water treatment composition can comprise calcium hypochlorite in the range of 50% to 100% by weight of the pool and / or water treatment composition. In an embodiment, the packet comprises a first coating comprising an acid scavenger provided on at least a portion of the inner surface of the outer wall.

[0162] In an embodiment, a unit dose article disclosed herein comprising a plurality of fibers comprising a blend of fiber-forming materials comprising (i) polyvinylpyrrolidone, and (ii) sulfonate-modified PVOH, carboxyl-modified PVOH, or both, can comprise a pool and / or water treatment composition contained in an inner pouch volume, the pool and / or water treatment composition can comprise calcium hypochlorite in the range of 50% to 100% by weight of the pool and / or water treatment composition. In an embodiment, the packet comprises a first coating comprising an acid scavenger provided on at least a portion of the inner surface of the outer wall.

[0163] Further provided herein is a process for dispensing a composition in bulk water, comprising contacting the bulk water with a water-soluble unit dose article as described herein, whereby at least a portion of the water-soluble nonwoven web dissolves and releases the composition into the bulk water. In an embodiment, the water-soluble unit dose article can include a water-soluble nonwoven web as described herein in the form of a packet defining an inner pouch volume, and a dispensing composition enclosed within the inner pouch volume, the water-soluble nonwoven web can include a water-soluble mixture of PVOH and PVP. In an embodiment, the PVOH and PVP are present in a ratio of about 95%:5% to about 25%:75% by weight, respectively.

[0164] Further provided herein is a process for metering a composition into bulk water, comprising contacting the bulk water with a unit dose article according to the present disclosure. In an embodiment, the bulk water dissolves at least a portion of the nonwoven web, releasing the composition into the bulk water. In an embodiment, the nonwoven web of the unit dose article can include a plurality of fibers comprising a blend of fiber-forming materials including (i) polyvinylpyrrolidone, and (ii) sulfonate-modified polyvinyl alcohol (PVOH), carboxyl-modified PVOH, or both. In an embodiment, the nonwoven web of the unit dose article can include a plurality of fibers comprising a sulfonate-modified PVOH fiber-forming material comprising sulfonated anionic monomer units, the sulfonate-modified PVOH fiber-forming material having a degree of hydrolysis of at least 95%, and the sulfonated anionic monomer is present in an amount ranging from about 1 mol% to about 5 mol%. In general, the bulk water can be any bulk water required to provide a non-household care composition therein. In an embodiment, the bulk water can be a pool or spa. Generally, the temperature of the bulk water can be any temperature sufficient to dissolve or disintegrate at least a portion of the water-soluble nonwoven web. In an embodiment, the bulk water has a temperature of at least about 10°C, for example, in the range of about 10°C to about 100°C, about 10°C to about 70°C, about 10°C to about 60°C, about 20°C to about 50°C, or about 20°C to about 40°C. Generally, the bulk water can have any pH. In an embodiment, the pH of the bulk water can be in the range of about 4 to about 10, about 5 to about 9, or about 6 to about 7.

[0165] Specific contemplated embodiments of the present disclosure herein are set forth in the following numbered paragraphs.

[0166] 1. (a) a blend of fiber-forming materials comprising (i) a carboxyl-modified polyvinyl alcohol (PVOH) and (ii) a sulfonate-modified polyvinyl alcohol, polyvinylpyrrolidone, or both; (b) a blend of fibers comprising (iii) a fiber comprising a carboxyl-modified polyvinyl alcohol fiber-forming material and (iv) a fiber comprising a sulfonate-modified polyvinyl alcohol fiber-forming material, a fiber comprising a polyvinylpyrrolidone fiber-forming material, or both; or (c) a blend of fibers comprising (v) a carboxyl-modified polyvinyl alcohol fiber-forming material, a sulfonate-modified polyvinyl alcohol fiber-forming material, or polyvinylpyrrolidone. 1. A water soluble nonwoven web comprising a plurality of fibers, the water soluble nonwoven web comprising a blend of fibers, the blend comprising: (i) a first fiber comprising a fiber forming material; and (ii) a second fiber comprising a blend of fiber forming materials comprising a carboxyl-modified polyvinyl alcohol fiber forming material, a sulfonate-modified polyvinyl alcohol fiber forming material, a polyvinylpyrrolidone fiber forming material, or a combination thereof, wherein in any of (a), (b), and (c), the weight ratio of the carboxyl-modified PVOH fiber forming material to the sulfonate-modified PVOH and / or the polyvinylpyrrolidone fiber forming material is from about 3:1 to about 19:1 by weight, respectively.

[0167] 2. The water soluble nonwoven web of paragraph 1, wherein the weight ratio of carboxyl modified polyvinyl alcohol fiber forming material to sulfonate and / or polyvinylpyrrolidone fiber forming material is from about 5:1 to about 15:1 by weight, from about 5:1 to about 12:1 by weight, from about 5:1 to about 9:1 by weight, from about 6:1 to about 9:1 by weight, or from about 6.5:1 to about 7.5:1 by weight, respectively.

[0168] 3. The water-soluble nonwoven web of any one of the preceding paragraphs, wherein the carboxyl-modified PVOH comprises maleate monomer units selected from the group consisting of monomethyl maleate, maleic acid, maleic anhydride, alkali salts thereof, and combinations thereof.

[0169] 4. The water soluble nonwoven web of paragraph 3, wherein the maleate monomer units are present in an amount ranging from about 1 mol % to 10 mol %, or from about 1 mol % to 8 mol %, or from about 1 mol % to 5 mol %.

[0170] 5. The water soluble nonwoven web of any one of the preceding paragraphs, wherein the sulfonate-modified PVOH comprises sulfonated anionic monomer units selected from the group consisting of vinyl sulfonic acid, allyl sulfonic acid, ethylene sulfonic acid, 2-acrylamido-1-methylpropanesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid (AMPS), 2-methylacrylamido-2-methylpropanesulfonic acid, 2-sulfoethyl acrylate, alkali salts thereof, or combinations thereof.

[0171] 6. The water-soluble nonwoven web of paragraph 5, wherein the sulfonated anionic monomer is present in an amount ranging from about 1 mol % to 10 mol %, or from about 1 mol % to 8 mol %, or from about 1 mol % to 5 mol %.

[0172] 7. A water-soluble nonwoven web, as described in any one of the preceding paragraphs, wherein the (a) fiber-forming material comprises polyvinylpyrrolidone, the (b) fiber comprises polyvinylpyrrolidone, or the (c) second fiber comprises a polyvinylpyrrolidone fiber-forming material.

[0173] 8. The water-soluble nonwoven web of any one of the preceding paragraphs, wherein the plurality of fibers further comprises a cellulosic modifier, a starch modifier, or both.

[0174] 9. The water-soluble nonwoven web of any one of the preceding paragraphs, further comprising an acid scavenger.

[0175] 10. The water-soluble nonwoven web, of paragraph 9, wherein the acid scavenger is selected from the group consisting of N-vinylpyrrolidone, sodium metabisulfite, activated olefins, allyl-based compounds, ethylene-containing compounds, quaternary ammonium compounds, tertiary amine-containing compounds, and combinations thereof.

[0176] 11. A water soluble nonwoven web according to paragraphs 9 or 10, wherein an acid scavenger is provided in or on the fibers, in or on the nonwoven web, or a combination of the foregoing.

[0177] 12. The water soluble nonwoven web of paragraph 11, wherein the acid scavenger is coated on the fibers, coated on the nonwoven web, or both.

[0178] 13. The water soluble nonwoven web of paragraph 11, wherein the acid scavenger is dispersed throughout the nonwoven web.

[0179] 14. The water-soluble nonwoven web of any one of the preceding paragraphs, further comprising an antioxidant.

[0180] 15. The water-soluble nonwoven web, according to paragraph 14, wherein the antioxidant is selected from the group consisting of propyl gallate, gallic acid, phenolic compounds, hindered amines, sodium metabisulfite, zinc acetate, and combinations thereof.

[0181] 16. A water-soluble nonwoven web according to paragraphs 14 or 15, wherein an antioxidant is provided in or on the fibers, in or on the nonwoven web, or a combination of the foregoing.

[0182] 17. The water soluble nonwoven web of paragraph 16, wherein the antioxidant is coated on the fibers, coated on the nonwoven web, or both.

[0183] 18. The water soluble nonwoven web of paragraph 16, wherein the antioxidant is dispersed throughout the nonwoven web.

[0184] 19. The water-soluble nonwoven web of any one of the preceding paragraphs, further comprising a plasticizer.

[0185] 20. The water soluble nonwoven web, of paragraph 19, wherein the plasticizer is selected from the group consisting of glycerin, diglycerin, sorbitol, ethylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, tetraethylene glycol, propylene glycol, polyethylene glycols up to 400 MW, neopentyl glycol, trimethylolpropane, polyether polyols, 2-methyl-1,3-propanediol, ethanolamine, maltitol, and combinations thereof.

[0186] 21. The water soluble nonwoven web, according to paragraph 20, wherein the plasticizer is selected from the group consisting of glycerol, maltitol, trimethylolpropane, and combinations thereof.

[0187] 22. The water-soluble nonwoven web of any one of the preceding paragraphs, further comprising a filler.

[0188] 23. The water-soluble nonwoven web, according to paragraph 22, wherein the filler is selected from the group consisting of high amylose starch, amorphous silica, hydroxyethylated starch, and combinations thereof.

[0189] 24. The water-soluble nonwoven web of any one of the preceding paragraphs, further comprising a surfactant.

[0190] 25. The water-soluble nonwoven web of paragraph 24, wherein the surfactant comprises a quaternary amine, myristyl dimethylamine oxide, an alkyl polyethylene glycol ether, a cocamide, or a combination thereof.

[0191] 26. The water-soluble nonwoven web of any one of paragraphs 1 to 25, wherein the water-soluble nonwoven web has a disintegration time of not more than 300 seconds in water at 23°C according to MSTM 205 after 8 weeks of exposure to a trichloroisocyanuric acid (TCCA) or sodium bisulfate (SBS) composition at 38°C and 80% RH atmosphere.

[0192] 27. The water soluble nonwoven web of paragraph 26, wherein the surface area of ​​the nonwoven web residue after testing according to MSTM 205 at 23° C. is less than about 50% of the surface area of ​​the nonwoven web before testing according to MSTM 205.

[0193] 28. After a water-soluble nonwoven web is exposed to a TCCA or SBS composition at 38°C and 80% RH for 8 weeks, the water-soluble nonwoven web has a β-dispersion coefficient of 3.5 or less, or less than 3.0 or less than 2.5. * 28. The water-soluble nonwoven web of any one of paragraphs 1 to 27, wherein the water-soluble nonwoven web maintains a water-soluble value.

[0194] 29. The water-soluble nonwoven web of any one of paragraphs 1 to 28, wherein the water-soluble nonwoven web maintains an average elongation of at least 90%, or at least 100%, or at least 120%, or at least 150%, or at least 175%, or at least 200% after 8 weeks of exposure to a TCCA or SBS composition at 38° C. and 80% RH atmosphere.

[0195] 30. A water-soluble unit dose article comprising: a packet including an outer wall, the outer wall having an outer surface and an inner surface defining an inner pouch volume, the outer wall comprising a water-soluble nonwoven web described in any one of the preceding paragraphs; and a composition contained in the inner pouch volume.

[0196] 31. The water-soluble unit dose article of paragraph 30, wherein the composition comprises an irritating chemical.

[0197] 32. The water soluble unit dose article of paragraph 31, wherein the irritating chemical comprises an acid, an oxidizing agent, a base, or a combination thereof.

[0198] 33. The water soluble unit dose article of paragraph 32, wherein the irritating chemical is a chlorine releasing compound.

[0199] 34. The water soluble unit dose article of paragraph 32, wherein the acid comprises sodium bisulfate, cyanuric acid, dichloroisocyanuric acid, trichloroisocyanuric acid, citric acid, hydrochloric acid, or a combination thereof.

[0200] 35. The water soluble unit dose article of paragraphs 32 or 33, wherein the oxidizing material comprises hypochlorous acid, hypochlorite, halogenated isocyanurates, chlorite, chlorate, perchlorate, bromate, perbromate, halogenated hydantoins, perborate, periodate, persulfate, permanganate, chromate, dichromate, nitrate, nitrite, peroxide, ketone peroxide, peroxyacid, inorganic acid, or combinations thereof.

[0201] 36. The water soluble unit dose article of paragraph 32, wherein the base comprises sodium carbonate, sodium bicarbonate, or a combination thereof.

[0202] 37. The water soluble unit dose article of any one of paragraphs 31 to 36, wherein the composition is a non-household care composition.

[0203] 38. The water soluble unit dose article of paragraph 37, wherein the non-household care composition is selected from the group consisting of agricultural compositions, aviation compositions, food and nutritional compositions, industrial compositions, livestock compositions, marine compositions, medical compositions, commercial compositions, military and / or paramilitary compositions, office compositions, recreational and / or park compositions, pet compositions, pool and / or water treatment compositions, and combinations thereof.

[0204] 39. The water soluble unit dose article of paragraph 38, wherein the non-household care composition is a pool and / or water treatment composition.

[0205] 40. The water soluble unit dose article of paragraphs 38 or 39, wherein the concentration of the acid, oxidizing agent, base, or combination thereof in the non-household care composition is in the range of 50% to 100% by weight, or 60% to 100% by weight, or 70% to 100% by weight, or 80% to 100% by weight, or 90% to 100% by weight, based on the total weight of the non-household care composition.

[0206] 41. The water soluble unit dose article of any one of paragraphs 30 to 40, wherein the packet further comprises a first coating comprising an acid scavenger, an antioxidant, or both, the first coating being in contact with the outer wall.

[0207] 42. The water soluble unit dose article of paragraph 41, wherein a first coating comprising an acid scavenger, an antioxidant, or a combination thereof is provided on at least a portion of the inner surface of the outer wall.

[0208] 43. The water-soluble unit dose article of paragraphs 41 or 42, wherein the packet further comprises a second coating comprising an acid scavenger, an antioxidant, or both.

[0209] 44. The water-soluble unit dose article of paragraph 43, wherein a first coating is provided on at least a portion of the inner surface of the outer wall and a second coating is provided on at least a portion of the outer surface of the pouch.

[0210] 45. The water soluble unit dose article of any one of paragraphs 41 to 44, wherein the acid scavenger comprises N-vinylpyrrolidone, sodium metabisulfite, zinc oxide, hydrotalcite, a metal stearate, an activated olefin, an allyl-based compound, a carboxylate compound, an ethylene-containing compound, a quaternary ammonium compound, a tertiary amine-containing compound, or a combination thereof.

[0211] 46. ​​The water soluble unit dose article of any one of paragraphs 41 to 45, wherein the antioxidant comprises propyl gallate, gallic acid, a phenolic compound, a hindered amine, sodium metabisulfite, zinc acetate, or a combination thereof.

[0212] 47. A water-soluble unit dose article comprising the water-soluble nonwoven web of any one of paragraphs 1 to 29 in the form of a packet having an outer wall having an outer surface and an inner surface defining an inner pouch volume, and a pool and / or water treatment composition contained in the inner pouch volume, wherein the concentration of the irritating chemical in the pool and / or water treatment composition is in the range of 50% to 100% by weight; the packet optionally comprising a first coating comprising an acid scavenger provided on at least a portion of the inner surface of the outer wall; A water-soluble unit dose article.

[0213] 48. A process for metering a composition into bulk water, the process comprising contacting the bulk water with a water soluble unit dose article described in any one of paragraphs 30 to 47. Elongation test

[0214] The elongation at break can be analyzed according to ASTM D 882. Briefly, an INSTRON® tensile testing machine (Model 5544 Tensile Tester or equivalent) is used for film data collection. For each measurement, a minimum of three test specimens, each cut using a reliable cutting tool, are tested in the machine direction (MD) (if applicable) to ensure dimensional stability and repeatability. Testing is performed in a standard laboratory atmosphere of 23±2.0°C and 35±5% relative humidity. A 1-inch wide (2.54 cm) sample of a single film sheet with a thickness of 3.0±0.15 mil (i.e., 76.2±3.8 μm) is prepared. The sample is then transferred to the INSTRON® tensile tester and proceeded with testing. The tensile tester is prepared, equipped with a 500 N load cell, and calibrated according to the manufacturer's instructions. Attach the compensating grips and faces (INSTRON® grips with model number 2702-032 faces, rubber coated, 25 mm wide, or equivalent). Mount the sample in the tensile tester and pull at a rate of 508 mm / min until the tensile stress drops by 10%. The elongation at which the 10% drop in tensile stress occurs is the elongation at break.

[0215] Suitable behavior of the films according to the present disclosure is characterized by an elongation value of at least about 90% as measured by an INSTRON® tester. In various embodiments, the films have an elongation value of at least 90%, at least 100%, at least 120%, at least 150%, at least 175%, or at least 200% after 8 weeks of exposure to a TCCA or SBS composition at 38° C. and 80% RH atmosphere. Dissolution, Disintegration and % Residue Test (MSTM 205)

[0216] The nonwoven web can be characterized by or tested for dissolution time and disintegration time according to methods known in the art, MonoSol Test Method 205 (MSTM 205), see, e.g., U.S. Patent No. 7,022,656.

[0217] Equipment and materials:

[0218] 600mL beaker

[0219] Magnetic stirrer (Labline model number 1250 or equivalent)

[0220] Magnetic stirring bar (5cm)

[0221] Thermometer (0~100℃±1℃)

[0222] Mold, stainless steel (3.8cm x 3.2cm)

[0223] Timer (0~300 seconds, accurate to the nearest second)

[0224] Polaroid® 35mm slide mount (or equivalent)

[0225] MonoSol 35mm Slide Mount Holder (or equivalent)

[0226] Distilled water

[0227] For each nonwoven web to be tested, three test specimens are cut from the nonwoven web sample, which are 3.8 cm by 3.2 cm specimens. When cutting from a single nonwoven web, the specimens should be cut from areas of the web that are evenly spaced along the cross direction of the web. Each test specimen is then analyzed using the following procedure.

[0228] Each specimen is mounted on a separate 35 mm slide mount.

[0229] Fill a beaker with 500 mL of distilled water. Use a thermometer to measure the water temperature and heat or cool the water, if necessary, to maintain a temperature of 20° C. (approximately 68° F.).

[0230] Record the height of the water column. Place a magnetic stirrer on the base of the holder. Place the beaker on the magnetic stirrer, add a magnetic stir bar to the beaker, start the stirrer, and adjust the stirring speed until a vortex appears that is approximately 1 / 5 the height of the water column. Record the depth of the vortex.

[0231] Secure the 35 mm slide mount in the alligator clamp of the 35 mm slide mount holder with the long end of the slide mount parallel to the water surface. The holder's depth adjustment should be set so that when lowered, the end of the clamp is 0.6 cm below the water surface. One of the short sides of the slide mount should be adjacent to the side of the beaker and the other directly above the center of the stir bar, so that the nonwoven web surface is perpendicular to the water flow.

[0232] In one motion, lower the secured slide and clamp into the water and start the timer. Disintegration occurs when the nonwoven web breaks apart. When all visible nonwoven web has been released from the slide mount, lift the slide out of the water and continue to monitor the solution for undissolved nonwoven web fragments. Dissolution occurs when all nonwoven web fragments are no longer visible and the solution is clear.

[0233] After 300 seconds, if any nonwoven web residue remained on the frame, the percentage of the surface area of ​​the nonwoven web that remained was estimated by visual inspection.

[0234] Results should include: complete sample identification, individual and average disintegration and dissolution times, and the water temperature in which the sample was tested.

[0235] The nonwoven web disintegration time (I) and the nonwoven web dissolution time (I) can be corrected to a standard or reference nonwoven web thickness using the exponential algorithm shown below in Equation 1 and Equation 2, respectively. I 補正値 =I 測定値 × (reference thickness / measured thickness) 1.93 [1] S補正値 =S 測定値 × (reference thickness / measured thickness) 1.83 [2] CIELab Test

[0236] The CIELab test is used to determine the reference yellowness of a sample using a Ci7600 spectrophotometer or equivalent. Required equipment and material(s)

[0237] X-Rite Ci7600 Benchtop Spectrophotometer

[0238] X-Rite Color Master Software

[0239] Black trap for reflectance calibration

[0240] Aperture plate with white ring

[0241] Sample holder

[0242] A transmission plaque to cover the reflectance aperture plate when completing transmission measurements

[0243] White calibration tile to cover the reflectance aperture plate when completing the calibration

[0244] Scissors for cutting out film samples Calibrating the Ci7600 Spectrophotometer

[0245] Note that for transmission measurements, an aperture plate with a white ring inside must be used. Open the Color Master software found on the desktop. In the Color Master software, go to the "Instruments" tab. Click Calibrate. Place the white calibration tile onto the aperture plate. The UV setting should be set to EXC400. Close the transmission cover by sliding the cover forward while lifting the locking pin. NOTE: You should hear the pin snap into place. Click "OK" on the software calibration prompt. Remove the tile from the aperture plate. Take the black trap from the accessory drawer and place it on the aperture plate. Make sure to leave the transmission cover closed and click "OK" on the software calibration prompt. Remove the black trap from the aperture plate. Place the transmission plaque onto the aperture plate. The calibration LED should be green if the calibration process is successful. Creation of standards (for transmission measurements)

[0246] Be sure to use an aperture plate with a white ring. Place the specimen clamp in the instrument. Place the transmission plaque on the aperture plate. Select the Instrument tab. Click Create Standards. Select Take Measurements using Attached Instrument and hit Next. Select if an average of measurements is required and indicate the number of measurements to take. Example: take 3 measurements for averaging. Place a 2x2 specimen in the transmission specimen clamp. Close the transmission cover by sliding the cover forward while lifting the locking pin. Click Measure and repeat for each sample. Click Next. Type the name of the standard. If selected, type a description for the standard. Click Next. If you want to change the tolerances or illuminant / observer specifications, click Modify and make the desired changes. Otherwise, select Next. If prompted to enter color classification data, select No and select Next. Select Finish. Selection of standards (for transmission measurements)

[0247] Select the "Database" tab. Click "Find Standards". Click on the appropriate standard required. The standard should be highlighted in blue. Then press "Select". The standard is ready to be used. To double check that the correct standard was selected, check the control box in the upper left hand corner of the program. This box should read the appropriate standard selected. Measurement of a sample (for transmission)

[0248] 1. Mount the appropriate aperture plate (with the white reflective ring) onto the measurement port at the front of the instrument. Place the white cap onto the aperture plate. Attach the specimen clamp and stop to the base with the thumbscrews. Select the "Instrument" tab. Click "Measure Trial". A window will pop up on the bottom left hand side of the screen with the name of the standard you are using. Move this window up so you can see it on the screen. If necessary, change the specifications, such as displaying the SPIN (includes specular reflectance) or SPEX (excludes specular reflectance) measurements, and the illuminant / observer specifications. Change the configuration to match the image below by clicking on the hyperlink under "Haze". Next to "Lot ID", type in the sample name of the sample you are measuring. Position the 2" x 2" sample in the center of the transmission sample holder and place it between the stop and clamp, facing the sphere. Always ensure the sample is level and parallel to the opening of the sphere. Close the cover. Hit F8 on your keyboard or click "Measure" in the right corner to take the measurement. You should hear a clicking noise and see a flash of light when the measurement is taken. Once the measurement is complete, remove the sample from the sample holder. If there is another sample, place it in the sample holder. Continue until all samples have been measured. Wait approximately one minute between sample measurements. Once the measurement is complete, exit the "Measure Trial" window. Reporting of test results

[0249] The given numerical data is CIE L * a * b * These values ​​represent various aspects of the color of the measured object. The L value quantifies how light or dark a color is, with black and white being the two extremes. The a value quantifies how red or green a color is, with positive a values ​​being more red and negative a values ​​being more green. The b value quantifies how yellow or blue a color is, with positive b values ​​being more yellow and negative b values ​​being more blue. Under F12 / 10 light source, L * a * b * The Spex numeric data given as the color measurement is recorded. EXAMPLES

[0250] Example 1 Exposure of PVOH nonwoven webs to irritating chemicals

[0251] Water-soluble nonwoven webs containing sulfonate modified PVOH or PVOH homopolymer fibers were formed into pouches containing trichloroisocyanuric acid ("TCCA") and / or calcium hypochlorite ("Cal Hypo"). The pouches were stored for 6 weeks at a temperature of 38°C and 80% RH in secondary packaging prepared from 4 mil HDPE film. Dissolution, disintegration, and / or % residue were measured according to MSTM 205, yellowness was measured according to the CIELab test, and % elongation was measured according to the Elongation Test. The results are provided in Table 1 below.

[0252] Dissolution / Disintegration: Samples were measured at 0, 2, 4, and 6 weeks unless the nonwoven web had not dissolved or disintegrated at those times, at which point the test was stopped. A shorter dissolution or disintegration time indicated that the nonwoven was more stable to irritating chemicals, and a longer dissolution or disintegration time at 6 weeks indicated that the nonwoven was less stable to irritating chemicals. [Table 1-1] [Table 1-2]

[0253] As seen in Table 1, water-soluble nonwoven webs were prepared using fibers containing either 2 mol% AMPS-modified PVOH with a degree of hydrolysis of 99+% or PVOH homopolymer with a viscosity of 23 cPs and a degree of hydrolysis of about 88 as the sole fiber-forming material component to determine the effect of irritating chemicals on various PVOH resins. In general, it was found that the AMPS-modified PVOH fibers and PVOH homopolymer fibers have poor dissolution after two weeks of exposure to acid-mediated oxidants (i.e., TCCA) at a temperature of 38° C. and 80% RH. However, the AMPS-modified PVOH fibers surprisingly showed acceptable disintegration (e.g., the nonwoven web disintegrates in less than 300 seconds according to MSTM 205) and acceptable discoloration (e.g., the nonwoven web has a color b of less than 3.5, and even less than 3.0 according to the CIELab test) after two, four, and even six weeks of exposure to base-mediated oxidants (e.g., calcium hypochlorite). * It was found that the .alpha.-methyl-.alpha.-phenylenediamine derivative had a value of .alpha.-methyl-.alpha.-phenylenediamine.

[0254] The foregoing description is given for clarity of understanding only, and no unnecessary limitations should be understood therefrom, since modifications within the scope of the invention may be apparent to those skilled in the art.

[0255] All patents, publications, and references cited herein are hereby incorporated by reference in their entirety. In the event of a conflict between this disclosure and the incorporated patents, publications, and references, this disclosure shall control. For example, the present invention provides the following: (Item 1) 1. A packet including an outer wall, the outer wall having an exterior surface and an interior surface defining an interior pouch volume, the outer wall comprising: (a) a sulfonate-modified PVOH fiber-forming material comprising sulfonated anionic monomer units, a sulfonate-modified PVOH fiber-forming material, the sulfonate-modified PVOH fiber-forming material having a degree of hydrolysis of at least 95% and the sulfonated anionic monomer is present in an amount ranging from about 1 mol % to about 5 mol %, or (b)(i) polyvinylpyrrolidone, and (ii) a modified polyvinyl alcohol (PVOH) containing sulfonate-modified PVOH, which contains sulfonated anionic monomer units, carboxyl-modified PVOH, which contains carboxylated anionic monomer units, or both; A blend of fiber forming materials comprising a packet comprising a nonwoven web comprising a plurality of fibers comprising and a composition contained in said inner pouch volume. (Item 2) 2. The unit dose article of claim 1, wherein the sulfonated anionic monomer unit is one or more selected from the group consisting of vinyl sulfonic acid, allyl sulfonic acid, ethylene sulfonic acid, 2-acrylamido-1-methylpropanesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid (AMPS), 2-methylacrylamido-2-methylpropanesulfonic acid, 2-sulfoethyl acrylate, and alkali salts of the foregoing. (Item 3) 3. The unit dose article of claim 2, wherein the sulfonated anionic monomer unit is AMPS. (Item 4) 4. The unit dose article of any one of items 1 to 3, wherein the sulfonated anionic monomer is present in an amount ranging from about 1 mol % to about 3 mol %. (Item 5) (a) the plurality of fibers further comprises fibers comprising cellulose, starch, carboxyl-modified PVOH comprising carboxylated anionic monomer units, or combinations thereof; or (b) said plurality of fibers comprising said sulfonate-modified PVOH fiber-forming material further comprises a fiber-forming material comprising cellulose, starch, polyvinylpyrrolidone, a carboxyl-modified PVOH comprising carboxylated anionic monomer units, or a combination thereof; or (c) a combination of (a) and (b); The unit dose article of any one of the preceding items. (Item 6) 7. The unit dose article of any one of the preceding items, wherein the nonwoven web further comprises an acid scavenger. (Item 7) 7. The unit dose article of claim 6, wherein the acid scavenger is one or more selected from the group consisting of N-vinylpyrrolidone, sodium metabisulfite, activated olefins, allyl-based compounds, ethylene-containing compounds, quaternary ammonium compounds, and tertiary amine-containing compounds. (Item 8) 8. The unit dose article of claim 6 or 7, wherein the acid scavenger is provided in or on the fibers, in or on the nonwoven web, or a combination of the foregoing. (Item 9) 9. The unit dose article of claim 8, wherein the acid scavenger is coated on the fibers, coated on the nonwoven web, or both. (Item 10) 9. The unit dose article of claim 8, wherein the acid scavenger is dispersed throughout the nonwoven web. (Item 11) 7. The unit dose article of any one of the preceding items, wherein the nonwoven web further comprises an antioxidant. (Item 12) 12. The unit dose article of claim 11, wherein the antioxidant is one or more selected from the group of propyl gallate, gallic acid, phenolic compounds, hindered amines, sodium metabisulfite, and zinc acetate. (Item 13) 13. The unit dose article of claim 11 or 12, wherein the antioxidant is provided in or on the fibers, in or on the nonwoven web, or a combination of the foregoing. (Item 14) 14. The unit dose article of claim 13, wherein the antioxidant is coated on the fibers, coated on the nonwoven web, or both. (Item 15) 12. The unit dose article of claim 11, wherein the antioxidant is dispersed throughout the nonwoven web. (Item 16) 7. The unit dose article of any one of the preceding items, wherein the nonwoven web further comprises a plasticizer. (Item 17) 17. The unit dose article of claim 16, wherein the plasticizer is one or more selected from the group of glycerin, diglycerin, sorbitol, ethylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, tetraethylene glycol, propylene glycol, polyethylene glycols up to 400 MW, neopentyl glycol, trimethylolpropane, polyether polyols, 2-methyl-1,3-propanediol, ethanolamine, and maltitol. (Item 18) 18. The unit dose article of claim 17, wherein the plasticizer is one or more selected from the group of glycerol, maltitol, and trimethylolpropane. (Item 19) 7. The unit dose article of any one of the preceding items, wherein the nonwoven web further comprises a filler. (Item 20) 20. The unit dose article of claim 19, wherein the filler is one or more selected from the group of high amylose starch, amorphous silica, and hydroxyethylated starch. (Item 21) 7. The unit dose article of any one of the preceding items, wherein the nonwoven web further comprises a surfactant. (Item 22) 22. The unit dose article of claim 21, wherein the surfactant comprises one or more of the group: quaternary amines, myristyl dimethylamine oxide, alkyl polyethylene glycol ethers, and cocamides. (Item 23) The unit dose article of any one of the preceding items, wherein the nonwoven web has a disintegration time of not more than 300 seconds according to MSTM 205 in water at 23° C. after six weeks of exposure to calcium hypochlorite at 38° C. and 80% RH atmosphere. (Item 24) The nonwoven web has a b of not more than 3.5, or not more than 3.0, or not more than 2.5 after being exposed to calcium hypochlorite for 6 weeks at 38° C. and 80% RH. * 8. The unit dose article of any one of the preceding items, which maintains a value. (Item 25) The unit dose article of any one of the preceding items, wherein the composition comprises an irritating chemical. (Item 26) 26. The unit dose article of claim 25, wherein the irritating chemical comprises an oxidizing agent, a base, or a combination thereof. (Item 27) 27. The unit dose article of claim 26, wherein the oxidizing agent is a chlorine-releasing compound. (Item 28) 28. The unit dose article of claim 26 or 27, wherein the oxidizing agent comprises one or more of hypochlorous acid, hypochlorite, halogenated isocyanurates, chlorite, chlorate, perchlorate, bromate, perbromate, halogenated hydantoins, perborate, periodate, persulfate, permanganate, chromate, dichromate, nitrate, nitrite, peroxide, ketone peroxide, peroxyacid, and inorganic acid. (Item 29) 26. The unit dose article of claim 25, wherein the irritating chemical comprises a base-mediated oxidizing agent. (Item 30) 30. The unit dose article of claim 29, wherein the base-mediated oxidizing agent comprises hypochlorite. (Item 31) 27. The unit dose article of claim 26, wherein the base comprises one or more of sodium carbonate and sodium bicarbonate. (Item 32) 32. The unit dose article of any one of items 25 to 31, wherein the composition is a non-household care composition. (Item 33) 33. The unit dose article according to item 32, wherein the non-household care composition is one or more selected from the group of agricultural compositions, aviation compositions, food and nutritional compositions, industrial compositions, livestock compositions, marine compositions, medical compositions, commercial compositions, military and / or paramilitary compositions, office compositions, entertainment and / or park compositions, pet compositions, and pool and / or water treatment compositions. (Item 34) 34. The unit dose article of claim 33, wherein the non-household care composition is a pool and / or water treatment composition. (Item 35) 35. The unit dose article according to item 33 or 34, wherein the concentration of the oxidizing material, the base, or a combination thereof in the non-household care composition is in the range of 50% to 100% by weight, or 60% to 100% by weight, or 70% to 100% by weight, or 80% to 100% by weight, or 90% to 100% by weight, based on the total weight of the non-household care composition. (Item 36) 36. The unit dose article of any one of items 24 to 35, wherein the packet further comprises a first coating comprising an acid scavenger, an antioxidant, or both, the first coating in contact with the exterior wall. (Item 37) 37. The unit dose article of claim 36, wherein the first coating is provided on at least a portion of the inner surface of the outer wall. (Item 38) 38. The unit dose article of claim 36 or 37, wherein the packet further comprises a second coating comprising an acid scavenger, an antioxidant, or both. (Item 39) 39. The unit dose article of claim 38, wherein the first coating is provided on at least a portion of the inner surface of the outer wall and the second coating is provided on at least a portion of the outer surface of the outer wall. (Item 40) 40. The unit dose article of any one of items 36 to 39, wherein the acid scavenger comprises one or more of N-vinylpyrrolidone, sodium metabisulfite, zinc oxide, hydrotalcite, metal stearates, activated olefins, allyl-based compounds, carboxylate compounds, ethylene-containing compounds, quaternary ammonium compounds, and tertiary amine-containing compounds. (Item 41) 41. The unit dose article of any one of items 36 to 40, wherein the antioxidant comprises one or more of propyl gallate, gallic acid, phenolic compounds, hindered amines, sodium metabisulfite, and zinc acetate. (Item 42) 3. The unit dose article of claim 2, wherein the weight ratio of the polyvinylpyrrolidone fiber-forming material to the carboxyl-modified polyvinyl alcohol fiber-forming material, the sulfonate fiber-forming material, or both, is from about 1:1 to about 1:19, 1:3 to about 1:19, from about 1:5 to about 1:15 by weight, from about 1:5 to about 1:12 by weight, from about 1:5 to about 1:9 by weight, from about 1:6 to about 1:9 by weight, or from about 1:6.5 to about 1:7.5 by weight, respectively. (Item 43) 43. The unit dose article of any one of items 2 to 42, wherein the carboxyl-modified PVOH comprises one or more maleate monomer units selected from the group of monomethyl maleate, maleic acid, maleic anhydride, and alkali salts thereof. (Item 44) 44. The unit dose article of item 43, wherein the maleate monomer units are present in an amount ranging from about 1 mol% to 10 mol%, or from about 1 mol% to 8 mol%, or from about 1 mol% to 5 mol%. (Item 45) A pool and / or water treatment composition is contained in the inner pouch volume, the pool and / or water treatment composition contains an oxidizing substance, and the concentration of the oxidizing substance in the pool and / or water treatment composition is in the range of 50% by weight to 100% by weight; 45. The unit dose article of any one of the preceding claims, wherein the oxidizing material comprises calcium hypochlorite and the packet optionally comprises a first coating comprising an acid scavenger provided on at least a portion of the inner surface of the outer wall. (Item 46) A pool and / or water treatment composition is contained in the inner pouch volume, the pool and / or water treatment composition contains an oxidizing substance, and the concentration of the oxidizing substance in the pool and / or water treatment composition is in the range of 50% by weight to 100% by weight; 45. The unit dose article of any one of the preceding claims, wherein the oxidizing material comprises trichloroisocyanuric acid and the packet optionally comprises a first coating comprising an acid scavenger provided on at least a portion of the inner surface of the outer wall. (Item 47) 47. A process for metering a composition into bulk water, the process comprising contacting the bulk water with a unit dose article according to any one of the preceding claims.

Claims

1. 1. A packet comprising an outer wall, the outer wall having an exterior surface and an interior surface defining an interior pouch volume, the outer wall comprising a nonwoven web comprising a plurality of fibers, the plurality of fibers comprising: (a) a sulfonate-modified PVOH fiber-forming material comprising a sulfonated anionic monomer unit, the sulfonated anionic monomer unit being 2-acrylamido-2-methylpropanesulfonic acid (AMPS); a sulfonate-modified PVOH fiber-forming material, wherein the sulfonate-modified PVOH fiber-forming material has a degree of hydrolysis of at least 95% and the sulfonated anionic monomer is present in an amount ranging from 1 mol % to 5 mol %, or (b)(i)(a) of the sulfonate-modified PVOH, (ii) polyvinylpyrrolidone, and / or (iii) modified polyvinyl alcohol (PVOH) containing sulfonate-modified PVOH, containing sulfonated anionic monomer units, carboxyl-modified PVOH, containing carboxylated anionic monomer units, or both. A blend of fiber-forming materials comprising in combination with A packet including: a composition contained in the inner pouch volume, the composition comprising a base-mediated oxidizing agent; and a unit dose article comprising:

2. 10. The unit dose article of claim 1, wherein the sulfonated anionic monomer is present in an amount ranging from 1 mol % to 3 mol %.

3. the plurality of fibers further comprises fibers comprising cellulose, starch, carboxyl-modified PVOH comprising carboxylated anionic monomer units, or combinations thereof; 2. The unit dose article of claim 1.

4. The unit dose article of claim 1 , wherein the nonwoven web further comprises an acid scavenger.

5. 5. The unit dose article of claim 4, wherein the acid scavenger is one or more selected from the group of N-vinylpyrrolidone, sodium metabisulfite, activated olefins, allyl-based compounds, ethylene-containing compounds, quaternary ammonium compounds, and tertiary amine-containing compounds.

6. 6. The unit dose article of claim 4 or 5, wherein the acid scavenger is provided in or on at least one fiber of the plurality of fibers, in or on the nonwoven web, or a combination of the foregoing.

7. 7. The unit dose article of claim 6, wherein the acid scavenger is coated on the fibers, coated on the nonwoven web, or both.

8. The unit dose article of claim 6 , wherein the acid scavenger is dispersed throughout the nonwoven web.

9. The unit dose article of claim 1 , wherein the nonwoven web further comprises an antioxidant.

10. 10. The unit dose article of claim 9, wherein the antioxidant is one or more selected from the group of propyl gallate, gallic acid, phenolic compounds, hindered amines, sodium metabisulfite, and zinc acetate.

11. 11. The unit dose article of claim 9 or 10, wherein the antioxidant is provided in or on at least one fiber of the plurality of fibers, in or on the nonwoven web, or a combination of the foregoing.

12. 12. The unit dose article of claim 11, wherein the antioxidant is coated on the fibers, coated on the nonwoven web, or both.

13. 10. The unit dose article of claim 9, wherein the antioxidant is dispersed throughout the nonwoven web.

14. The unit dose article of claim 1 , wherein the nonwoven web further comprises a plasticizer.

15. 15. The unit dose article of claim 14, wherein the plasticizer is one or more selected from the group of glycerin, diglycerin, sorbitol, ethylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, tetraethylene glycol, propylene glycol, polyethylene glycols up to 400 MW, neopentyl glycol, trimethylolpropane, polyether polyols, 2-methyl-1,3-propanediol, ethanolamine, and maltitol.

16. 16. The unit dose article of claim 15, wherein the plasticizer is one or more selected from the group of glycerol, maltitol, and trimethylolpropane.

17. The unit dose article of claim 1 , wherein the nonwoven web further comprises a filler.

18. 20. The unit dose article of claim 17, wherein the filler is one or more selected from the group of high amylose starch, amorphous silica, and hydroxyethylated starch.

19. The unit dose article of claim 1 , wherein the nonwoven web further comprises a surfactant.

20. 20. The unit dose article of claim 19, wherein the surfactant comprises one or more of the group: quaternary amines, myristyl dimethylamine oxide, alkyl polyethylene glycol ethers, and cocamides.

21. 10. The unit dose article of claim 1, wherein the nonwoven web has a disintegration time of not more than 300 seconds according to MSTM 205 in water at 23°C after six weeks of exposure to calcium hypochlorite in a 38°C and 80% RH atmosphere.

22. The nonwoven web has a b of not more than 3.5 after being exposed to calcium hypochlorite for 6 weeks in an atmosphere of 38° C. and 80% RH. ＊ The unit dose article of claim 1 , wherein the unit dose article maintains a value.

23. 10. The unit dose article of claim 1, wherein the base-mediated oxidizing material comprises hypochlorite.

24. 24. The unit dose article of claim 1 or 23, wherein the composition is a non-household care composition.

25. 25. The unit dose article of claim 24, wherein the non-household care composition is one or more selected from the group of agricultural compositions, aviation compositions, food and nutritional compositions, industrial compositions, livestock compositions, marine compositions, medical compositions, commercial compositions, military and / or paramilitary compositions, office compositions, entertainment and / or park compositions, pet compositions, and pool and / or water treatment compositions.

26. 26. The unit dose article of claim 25, wherein the non-household care composition is a pool and / or water treatment composition.

27. 27. The unit dose article of claim 25 or 26, wherein the concentration of the base-mediated oxidizing material in the non-household care composition ranges from 50% to 100% by weight, based on the total weight of the non-household care composition.

28. 28. The unit dose article of any one of claims 23-27, wherein the packet further comprises a first coating comprising an acid scavenger, an antioxidant, or both, the first coating in contact with the exterior wall.

29. 30. The unit dose article of claim 28, wherein the first coating is provided on at least a portion of the inner surface of the outer wall.

30. 30. The unit dose article of claim 28 or 29, wherein the packet further comprises a second coating comprising an acid scavenger, an antioxidant, or both.

31. 31. The unit dose article of claim 30, wherein the first coating is provided on at least a portion of the inner surface of the outer wall and the second coating is provided on at least a portion of the outer surface of the outer wall.

32. 32. The unit dose article of any one of claims 28-31, wherein the acid scavenger comprises one or more of N-vinylpyrrolidone, sodium metabisulfite, zinc oxide, hydrotalcite, metal stearates, activated olefins, allylic compounds, carboxylate compounds, ethylene-containing compounds, quaternary ammonium compounds, and tertiary amine-containing compounds.

33. 33. The unit dose article of any one of claims 28-32, wherein the antioxidant comprises one or more of propyl gallate, gallic acid, phenolic compounds, hindered amines, sodium metabisulfite, and zinc acetate.

34. 2. The unit dose article of claim 1, wherein a weight ratio of said polyvinylpyrrolidone fiber-forming material of b(ii) to said carboxyl-modified polyvinyl alcohol fiber-forming material of b(iii), said sulfonate-modified PVOH fiber-forming material of b(iii), or both, is from 1:1 to 1:

19.

35. 35. The unit dose article of any one of claims 1 to 34, wherein the carboxyl-modified PVOH comprises one or more maleate monomer units selected from the group of monomethyl maleate, maleic acid, maleic anhydride, and alkali salts thereof.

36. 36. The unit dose article of claim 35, wherein the maleate monomer units are present in an amount ranging from 1 mol % to 10 mol %.

37. a pool and / or water treatment composition is contained in the inner pouch volume, the pool and / or water treatment composition comprises the base-mediated oxidizer, and the concentration of the base-mediated oxidizer in the pool and / or water treatment composition is in the range of 50% to 100% by weight; 37. The unit dose article of any one of claims 1-36, wherein the base-mediated oxidizing material comprises calcium hypochlorite and the packet optionally comprises a first coating comprising an acid scavenger provided on at least a portion of the interior surface of the outer wall.

38. 38. A process for metering a composition into bulk water, comprising contacting the bulk water with a unit dose article according to any one of claims 1 to 37.

Images