Mixed starch / PVOH water soluble film

Abstract

Provided herein are water-soluble films comprising a water-soluble polymer, such as polyvinyl alcohol (PVOH), and a high content of water-soluble starch, as well as related water-soluble film-forming solutions, articles (e.g., pouches or packets) made therefrom, and methods of making and using the same.

Description

[0001] Cross - Reference to Related Applications

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 477,561, filed on Dec. 28, 2022, under 35 U.S.C. § 119(e), and the entire disclosure thereof is incorporated herein by reference. TECHNICAL FIELD

[0003] The present disclosure generally relates to water-soluble films and related solutions for forming water-soluble films, articles including pouches or sachets made therefrom, and methods for their preparation and use. More specifically, the present disclosure relates to water-soluble films that comprise a water-soluble polymer such as polyvinyl alcohol (PVOH) and a high content of starch, and related solutions for forming water-soluble films, articles (e.g., pouches or sachets) made therefrom, and methods for their preparation and use. BACKGROUND ART

[0004] Water-soluble polymeric films are commonly used as packaging materials for facilitating the dispersion, pouring, dissolution, and dispensing of compositions to be delivered. For example, sachets made of water-soluble films are commonly used for packaging household care compositions, such as pouches containing laundry detergents or dishwashing detergents. Consumers can directly add the packaged composition in the sachet to a mixing container such as a bucket, sink, or any container suitable for holding water. Advantageously, this provides precise dosing while eliminating the need for consumers to measure the composition. The packaged composition can also reduce the hassle associated with dispensing the composition from a product container, such as pouring or scooping the material. In summary, soluble pre-measured polymeric film sachets provide convenience for consumers in various applications.

[0005] Currently, consumers are increasingly inclined to use environmentally friendly or renewable products. However, one problem with traditional water-soluble films is that such films are generally not environmentally friendly or non-renewable and typically have a low renewable carbon index (RCI). In addition, due to the very rigid nature of many renewable components and their immiscibility or incompatibility with other polymer components in traditional water-soluble films, their use in these films is limited because mechanical properties suitable for conversion into and use as packaging, such as high levels of elongation, deformation recovery, and strength properties, need to be maintained. SUMMARY OF THE INVENTION

[0006] The embodiments disclosed herein meet the above needs by providing sustainable water-soluble films that can be used with consumer products compositions such as liquid detergents, and sustainable consumer product compositions packaged in the sustainable water-soluble films, thereby producing highly sustainable eco-friendly consumer products. The water-soluble films can have a high renewable carbon index (RCI) of 50% or higher and also have desired physical properties.

[0007] One aspect of the present disclosure provides a water-soluble film comprising: water-soluble polyvinyl alcohol (PVOH); and water-soluble starch, wherein the gelatinization % of the water-soluble starch is at least about 5 WT.%, wherein the water-soluble starch may be present in an amount of about 5-65 WT.% based on the weight of the water-soluble film, and wherein the PVOH and the water-soluble starch are miscible in the water-soluble film or the phase domains are less than 2000 μM. The water-soluble polyvinyl alcohol may be soluble in water at a temperature of about 60 °C or lower in about 60 minutes, or soluble in water at a temperature of about 60 °C in about 60 minutes, soluble in water at a temperature of about 40 °C in about 60 minutes, soluble in water at a temperature of about 20 °C in about 60 minutes or soluble in water at a temperature of about 10 °C in about 60 minutes. The water-soluble polyvinyl alcohol may comprise anionic group-modified polyvinyl alcohol. The water-soluble starch may comprise cationic group-modified starch. The water-soluble starch may comprise neutral group-modified starch.

[0008] Another aspect of the present disclosure provides an aqueous solution suitable for forming the water-soluble film of the present disclosure, the aqueous solution comprising: water-soluble polyvinyl alcohol (PVOH); water-soluble starch; and water, wherein the gelatinization % of the water-soluble starch is at least about 5 WT.%, wherein the total solids content of the aqueous solution is at least 15 WT.% based on the weight of the aqueous solution, wherein the water-soluble starch may be present in an amount of about 5-65 WT.% based on the weight of the total solids content, and wherein the water-soluble polyvinyl alcohol (PVOH) and the water-soluble starch are miscible or have no bulk phase separation in the aqueous solution for at least 24 hours by visual inspection at a temperature in the range of about 20 °C to 100 °C.

[0009] Another aspect of the present disclosure provides a method of forming the water-soluble film of the present disclosure, the method comprising: casting the aqueous solution of the present disclosure onto a substrate to a specified thickness; and drying the water in the cast aqueous solution to form the water-soluble film.

[0010] Another aspect of the present disclosure provides an article comprising a sachet or packet made of the water-soluble film of the present disclosure, the sachet or packet defining an internal sachet volume. The article may further comprise a consumer product or chemical composition contained in the internal sachet volume and encapsulated within the sachet.

[0011] For the water-soluble films, aqueous solutions for forming water-soluble films, and articles described herein, optional features may be envisioned as being selected from the various aspects and embodiments provided herein, including but not limited to components and their compositional ranges, film-forming materials, film-forming solution compositions and features, and / or mechanical properties.

[0012] By reviewing the following detailed description, additional aspects and advantages will become apparent to those of ordinary skill in the art. While the water-soluble films, aqueous solutions, and articles of the present disclosure admit of various forms of embodiments, the following description includes specific embodiments, where it should be understood that the present disclosure is illustrative and not intended to limit the present disclosure to the specific embodiments described herein. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] To further facilitate understanding of the present disclosure, the accompanying drawings are attached herein. The drawings described herein are for illustrative purposes only for the selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

[0014] Figure 1A and 1B respectively show the single-phase aqueous solution images of Sample 2 with Starch A and Resin A at a starch loading level of 55 PHR; and the solution phase separation images of Aqueous Solution Sample 6 with Starch E and Resin A at a starch loading level of 49 PHR.

[0015] Figure 2 The cold water dissolution and disintegration times of the film according to Example 1 are plotted.

[0016] Figures 3A to 3C are micrographs of the stretched and unstretched films as described in Example 2.

[0017] Figure 4 is a graph showing the film moisture content as a function of ambient humidity as described in Example 8.

[0018] Figure 5 is a graph showing the results of the dynamic vapor sorption test as described in Example 8. DETAILED DESCRIPTION

[0019] The foregoing description of the technology is essentially only an example of one or more of the subject matters, manufacture, and use of the present invention, and is not intended to limit the scope, application, or use of any particular invention claimed in this application, or the scope, application, or use of other applications that may claim priority from this application or patents issued therefrom. A non-limiting discussion of terms and phrases is provided at the end of this detailed description, intended to assist in understanding the technology of the present invention.

[0020] Traditional water-soluble films have high raw material costs due to the high content of water-soluble polymers (such as polyvinyl alcohol (PVOH)) in the formulation. PVOH is typically a petroleum-derived polymer product. The increase in oil prices and the consequent petroleum-derived products have led to fluctuations in the prices and supplies of many polymer products. The present invention can be used to replace petroleum-based polymers with polymers derived from renewable sources such as plants, as such materials are relatively cheaper and more environmentally friendly and are thus beneficial both economically and socially. Previously, for processes for forming water-soluble films (e.g., solution casting), it has been challenging to achieve the desired miscibility of water-soluble polymers with high load levels of renewable components such as starch in aqueous solutions, which in turn leads to phase separation of the water-soluble polymer and the renewable component, and in the resulting water-soluble films, either no film can be formed or the degree of phase separation of the water-soluble polymer and the renewable component is unacceptable. Water-soluble films previously employing high levels of renewable components such as starch also have one or more disadvantages, including poor processability, high brittleness, limited flexibility, poor water solubility, low sachet compressive strength, and poor mechanical strength characteristics.

[0021] The present disclosure provides a water-soluble film that includes water-soluble polyvinyl alcohol and a water-soluble starch at a high starch load level, as well as related aqueous solutions for forming the water-soluble film, sachet, or packet, and methods for preparing and using the water-soluble film.

[0022] One aspect of the present disclosure provides a water-soluble film that includes: water-soluble polyvinyl alcohol (PVOH); and water-soluble starch, wherein the gelatinization % of the water-soluble starch is at least about 5 wt.%, wherein the water-soluble starch is present in an amount of about 5 - 65 wt.% based on the weight of the water-soluble film, and wherein the PVOH and the water-soluble starch are miscible in the water-soluble film, or the phase domains are less than about 2000 μm, about 1500 μm, about 1000 μm, about 900 μm, about 800 μm, about 700 μm, about 600 μm, about 500 μm, about 400 μm, about 300 μm, about 200 μm, about 100 μm, about 90 μm, about 80 μm, about 70 μm, about 60 μm, about 50 μm, about 40 μm, about 30 μm, about 20 μm, about 10 μm, or even about 1 μm. The domain size can be measured by various methods such as atomic force microscopy (AFM), time-of-flight secondary ion mass spectrometry (ToF-SIMS), and refractometry (including optical refractometry and X-ray refractometry). In one aspect, the domain size can be measured by AFM.

[0023] As used herein and unless otherwise specified, the term "water-soluble polyvinyl alcohol" refers to polyvinyl alcohol that is soluble in water at a temperature of about 60°C within about 60 minutes, about 50 minutes, about 40 minutes, about 30 minutes, about 20 minutes, about 10 minutes, about 5 minutes, or about 3 minutes. The water-soluble polyvinyl alcohol may be soluble in water at a temperature of about 40°C within about 60 minutes, about 50 minutes, about 40 minutes, about 30 minutes, about 20 minutes, about 10 minutes, about 5 minutes, or about 3 minutes. The water-soluble polyvinyl alcohol may be soluble in water at a temperature of about 10°C within about 60 minutes, about 50 minutes, about 40 minutes, about 30 minutes, about 20 minutes, about 10 minutes, about 5 minutes, or about 3 minutes.

[0024] The water-soluble polyvinyl alcohol may comprise one or more polyvinyl alcohol homopolymers and / or copolymers, for example, one or more homopolymers and / or copolymers selected from unmodified polyvinyl alcohol, polyvinyl alcohol modified with nonionic groups, polyvinyl alcohol modified with anionic groups, and polyvinyl alcohol modified with cationic groups. The water-soluble polyvinyl alcohol may comprise polyvinyl alcohol modified with anionic groups. The water-soluble starch may comprise one or more starches selected from the following: unmodified starch, starch modified with nonionic groups, starch modified with anionic groups, and starch modified with cationic groups. The water-soluble starch may comprise starch modified with cationic groups. The water-soluble polyvinyl alcohol may comprise polyvinyl alcohol modified with anionic groups, and the water-soluble starch may comprise starch modified with cationic groups.

[0025] The water-soluble film may be a free-standing film, i.e., a film that does not require a substrate to maintain the integrity of the film structure, and optionally a film that does not include such a substrate.

[0026] For example, the water-soluble film may have any renewable carbon index (RCI) and is optionally one of the following: at least about 30%, 40%, 50%, 55%, 60%, 65%, 70%, or 80%, or in the range of about 50 - 90% or in the range of about 50 - 80%.

[0027] The water-soluble starch may comprise substantially gelatinized starch.

[0028] For example, the gelatinization % of the water-soluble starch can be at least about 5 wt.%, at least 6 wt.%, at least about 7 wt.%, at least about 8 wt.%, at least about 9 wt.%, at least about 10 wt.%, at least about 11 wt.%, at least about 12 wt.%, at least about 13 wt.%, at least about 14 wt.%, at least about 15 wt.%, at least about 16 wt.%, at least about 17 wt.%, at least about 18 wt.%, at least about 19 wt.%, at least about 20 wt.%, at least about 21 wt.%, at least about 22 wt.%, at least about 23 wt.%, at least about 24 wt.%, at least about 25 wt.%, at least about 26 wt.%, at least about 27 wt.%, at least about 28 wt.%, at least about 29 wt.%, or at least about 30 wt.%, or within a relevant range, such as at least 10 wt.% and at most 40 wt.% or at least 10 wt.% and at most 30 wt.%. The gelatinization % of the water-soluble starch can be at least about 15 wt.%.

[0029] The average molecular weight of the water-soluble starch can be about 10 3 -10 7 g / mol, or about 10 3 -10 6 g / mol or about 10 4 -10 5 g / mol.

[0030] The amylose content contained in the water-soluble starch can be within the range of about 0 - 50 wt.%, about 0 - 40 wt.%, about 0 - 30 wt.%, or about 0 - 25 wt.% of the water-soluble starch.

[0031] The Brookfield viscosity of a 5 wt.% aqueous solution of the water-soluble starch at a shear rate of about 20 rpm and a temperature of about 87.8 °C can be within the range of about 1 - 2000 cP, about 1 - 1500 cP, about 1 - 1000 cP, about 1 - 900 cP, about 1 - 800 cP, about 1 - 700 cP, about 1 - 600 cP, about 1 - 500 cP, about 2 - 400 cP, about 2 - 300 cP, about 2 - 200 cP, or about 2 - 100 cP.

[0032] Based on the weight of the water-soluble film, the water-soluble starch can be present in an amount of about 10 - 65 wt.%, 15 - 65 wt.%, 20 - 60 wt.%, about 25 - 60 wt.%, about 30 - 60 wt.%, about 30 - 55 wt.%, about 30 - 50 wt.%, or about 30 - 45 wt.%.

[0033] According to the accelerated quantitative residue evaluation test method described below, the water-soluble film can dissolve in water at a temperature of about 15 °C, leaving a residue of less than about 10 wt.%, about 5.0 wt.%, about 4.0 wt.%, about 3.0 wt.%, about 2.5 wt.% or about 2.0 wt.% based on the weight of the water-soluble film. The residue at a temperature of about 15 °C can be measured. For example, the residue left at a temperature of about 15 °C is less than 5.0 wt.% based on the weight of the water-soluble film.

[0034] The water-soluble starch may include unmodified starch.

[0035] The water-soluble starch may include starch modified with neutral groups or non-ionic groups, and the modification level is optionally about 0.1-10 mol.% or about 1-5 mol.%.

[0036] The water-soluble starch may include starch modified with cationic groups, and the degree of modification is optionally about 0.01-10 mol.%, about 0.1-5 mol.%, about 0.1-2 mol.% or about 0.1-0.5 mol.%.

[0037] The starch modified with cationic groups may include, for example, starch modified with a cationic quaternary ammonium group having the structure of formula A, where R1, R2 and R3 are each independently H or C1-C 10 alkyl or C1-C 10 hydroxyalkyl, and R4 is a straight-chain or branched C1-C 10 alkylene or C1-C 10 hydroxyalkylene, optionally substituted with one or more heteroatom-containing groups, and where X is an ether or ester bond connecting R4 to the starch, or a hydrocarbon group containing oxygen, nitrogen or sulfur.

[0038]

[0039] R1, R2 and R3 may be the same C1-C4 alkyl, and R4 may be a straight-chain or branched C1-C6 hydroxyalkylene. On the other hand, R4 may be a C3-C6 hydroxyalkylene. On the other hand, R1, R2 and R3 may each be methyl, and R4 may be a C3-C6 hydroxyalkylene.

[0040] The cationic quaternary ammonium group may be a quaternary 2-hydroxy-3-(trimethylammonium)propyl, 2-diethylaminoethyl or 2,3-epoxypropyltrimethylammonium group or a combination thereof.

[0041] The starch modified with cationic groups may include starch modified with a cationic trimethylammonium group.

[0042] The starch modified with cationic groups may include starch modified with the following: 2-diethylaminoethyl salts, 2,3-epoxypropyltrimethylammonium salts, or 2-hydroxy-3-(trimethylammonium)propyl salts, or combinations thereof.

[0043] The 2-diethylaminoethyl salts may include 2-diethylaminoethyl halides, the 2,3-epoxypropyltrimethylammonium salts may include 2,3-epoxypropyltrimethylammonium halides, and the 2-hydroxy-3-(trimethylammonium)propyl salts may include 2-hydroxy-3-(trimethylammonium)propyl halides.

[0044] The 2-diethylaminoethyl salts may include 2-diethylaminoethyl chloride, the 2,3-epoxypropyltrimethylammonium salts may include 2,3-epoxypropyltrimethylammonium chloride, and the 2-hydroxy-3-(trimethylammonium)propyl salts may include 2-hydroxy-3-(trimethylammonium)propyl chloride.

[0045] The water-soluble starch may further include unmodified starch and / or starch modified with non-ionic groups, with a modification level of about 0.05 - 5 mol%, or about 0.5 - 5 mol%, or about 1 - 5 mol%.

[0046] The water-soluble polyvinyl alcohol may include unmodified polyvinyl alcohol, polyvinyl alcohol modified with anionic groups, polyvinyl alcohol modified with cationic groups, or combinations thereof.

[0047] The polyvinyl alcohol may include polyvinyl alcohol modified with anionic groups, with the degree of modification in the range of about 0.1 - 10 mol.% or about 1.0 - 5.0 mol.%.

[0048] The polyvinyl alcohol modified with anionic groups may include polyvinyl alcohol modified with one or more groups derived from the following: itaconic acid, monomethyl maleate (MMM), methyl acrylate (MA), aminopropyl sulfonate, maleic acid, maleic anhydride, vinyl pyrrolidone, vinyl pyrrolidone, vinyl caprolactam, derivatives of any of the foregoing, or combinations thereof.

[0049] The polyvinyl alcohol modified with anionic groups may include the polyvinyl alcohol modified with the following: monomethyl maleate, methyl acrylate, or combinations thereof.

[0050] The water-soluble film may further include a plasticizer, which is present in the range of about 5.0 - 50.0 wt.%, about 5.0 - 40.0 wt.%, or 10.0 - 40.0 wt.% based on the weight of the water-soluble film.

[0051] The plasticizer may include sorbitol, glycerine, glycerol, diglycerol, propylene glycol, dipropylene glycol, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol with a molecular weight of up to 400, 2-methyl-1,3-propanediol, ethanolamine, trimethylolpropane (TMP), polyether polyol, isomaltitol, maltitol, xylitol, erythritol, adonitol, galactitol, pentaerythritol, mannitol, sugar alcohol, or a combination thereof.

[0052] The plasticizer may include a bio-based plasticizer. The bio-based plasticizer may include glycerol and / or sorbitol.

[0053] The water-soluble film may further include a surfactant.

[0054] The surfactant may include a linear aliphatic ethoxylated surfactant. The linear aliphatic ethoxylated surfactant may include lauryl polyether-6 formate, C9-C 15 ethylene oxide, or a combination thereof.

[0055] The water-soluble film may further include one or more additives from the following groups: defoamer, antioxidant, disinfectant, anti-blocking agent, filler, sodium metabisulfite, sodium hydroxide, matting agent, slip agent, dispersant, or a combination thereof.

[0056] According to MSTM-205, at a temperature of about 40°C, the dissolution time of the water-soluble film in water may not exceed 300 seconds or may be in the range of 30 - 300 seconds. At a temperature of about 30°C, or about 20°C, or about 15°C, the dissolution time in water may not exceed 300 seconds or may be in the range of 30 - 300 seconds. At a temperature of about 10°C or alternatively about 5°C, the dissolution time in water may be in the range of 30 - 300 seconds.

[0057] The maximum stress of the water-soluble film may be at least about 10 MPa, about 11 MPa, about 12 MPa, about 13 MPa, about 14 MPa, about 15 MPa, about 16 MPa, about 17 MPa, about 18 MPa, about 19 MPa, or about 20 MPa. The maximum stress is the breaking stress of the water-soluble film.

[0058] The breaking strain of the water-soluble film may be at least about 100%, about 150%, about 160%, about 170%, about 180%, about 190%, about 200%, about 210%, about 220%, about 230%, about 240%, or about 250%.

[0059] The weight ratio of polyvinyl alcohol to water-soluble starch can be in the range of about 10:1 to about 1:8, about 9:1 to about 1:7, about 6:1 to about 1:6, or about 5:1 to about 1:6, or about 4:1 to 1:2 or about 4:1 to about 1:1.

[0060] The degree of hydrolysis of the polyvinyl alcohol can be in the range of about 74 mol.% to about 99 mol.% or about 74 mol.% to about 91 mol.%.

[0061] The water-soluble film may comprise: polyvinyl alcohol modified with water-soluble anionic groups to a degree of about 1-5 mol.%; and starch modified with water-soluble cationic groups to a degree of about 0.05-5 mol.%, and having a Brookfield viscosity of a 5 wt.% aqueous solution at about 20 rpm and about 87.8 °C in the range of about 1-200 cP, wherein the gelatinization % of the cationic group-modified starch is at least about 5 wt.%, wherein the cationic group-modified starch is present in an amount in the range of about 20-60 wt.% based on the weight of the water-soluble film, and wherein the anionic group-modified PVOH and the cationic group-modified starch are miscible in the water-soluble film, or the phase domains are less than 2000 μm, about 1500 μm, about 1000 μm, about 900 μm, about 800 μm, about 700 μm, about 600 μm, about 500 μm, about 400 μm, about 300 μm, about 200 μm, about 100 μm, about 90 μm, about 80 μm, about 70 μm, about 60 μm, about 50 μm, about 40 μm, about 30 μm, about 20 μm, about 10 μm or about 1 μm.

[0062] Another aspect of the present disclosure provides an aqueous solution for forming the water-soluble film of the present disclosure, the aqueous solution comprising: water-soluble polyvinyl alcohol (PVOH); water-soluble starch; and water, wherein the gelatinization % of the water-soluble starch is at least about 5 wt.%, wherein the total solids content of the aqueous solution is at least 15 wt.% based on the weight of the aqueous solution, wherein the water-soluble starch is present in an amount of about 5-65 wt.% based on the weight of the total solids content, and wherein the water-soluble polyvinyl alcohol and the water-soluble starch are miscible or free of bulk phase separation in the aqueous solution for at least 24 hours by visual inspection at temperatures in the range of about 5-100 °C. Aspects of such a film-forming solution will now be described.

[0063] Water-soluble polyvinyl alcohol can be soluble in water at a temperature of about 60°C within about 60 minutes, about 50 minutes, about 40 minutes, about 30 minutes, about 20 minutes, about 10 minutes, about 5 minutes or about 3 minutes. Water-soluble polyvinyl alcohol can be soluble in water at a temperature of about 40°C within about 60 minutes, about 50 minutes, about 40 minutes, about 30 minutes, about 20 minutes, about 10 minutes, about 5 minutes or about 3 minutes. The water-soluble polyvinyl alcohol can be soluble in water at a temperature of about 40°C within about 10 minutes. Water-soluble polyvinyl alcohol can be soluble in water at a temperature of about 20°C within about 60 minutes, about 50 minutes, about 40 minutes, about 30 minutes, about 20 minutes, about 10 minutes, about 5 minutes or about 3 minutes.

[0064] The renewable carbon index (RCI) of the total solid content can be at least about 30%, or about 40%, or about 50%, or about 60%, or about 70%, or about 80%, or about 85% or about 60%, or in the range of about 50 - 90% or about 50 - 80%.

[0065] The water-soluble starch may comprise substantially gelatinized starch.

[0066] The gelatinization % of the water-soluble starch can be at least about 5 wt.%, at least about 6 wt.%, at least about 7 wt.%, at least about 8 wt.%, at least about 9 wt.%, at least about 10 wt.%, at least about 11 wt.%, at least about 12 wt.%, at least about 13 wt.%, at least about 14 wt.%, at least about 15 wt.%, at least about 16 wt.%, at least about 17 wt.%, at least about 18 wt.%, at least about 19 wt.%, at least about 20 wt.%, at least about 21 wt.%, at least about 22 wt.%, at least about 23 wt.%, at least about 24 wt.%, at least about 25 wt.%, at least about 26 wt.%, at least about 27 wt.%, at least about 28 wt.%, at least about 29 wt.% or about 30 wt.%. The gelatinization % of the water-soluble starch is at least about 15 wt.%.

[0067] The average molecular weight of the water-soluble starch can be about 10 3 -10 6 g / mol or about 10 4 -10 5 g / mol in the range.

[0068] The amylose content contained in the water-soluble starch can be in the range of about 0 - 50 wt.%, about 0 - 40 wt.% or about 0 - 30 wt.% of the water-soluble starch.

[0069] The Brookfield viscosity of the aqueous solution of the water-soluble starch at a shear rate of about 20 rpm and a temperature of about 87.8 °C can be in the range of about 1 - 2000 cP, about 1 - 1500 cP, about 1 - 1000 cP, about 1 - 900 cP, about 1 - 800 cP, about 1 - 700 cP, about 1 - 600 cP, about 1 - 500 cP, about 2 - 400 cP, about 2 - 300 cP, about 2 - 200 cP or about 2 - 100 cP.

[0070] By weight of the aqueous solution, the total solids content of the aqueous solution can be at least about 20 wt.%, about 25 wt.% or about 32 wt.%, or in the range of about 15 - 45 wt.%, about 20 - 40 wt.%, about 25 - 38 wt.% or about 28 - 35 wt.%. The total solids content can be in the range of about 25 - 40 wt.% or about 28 - 35 wt.% of the aqueous solution.

[0071] By weight of the total solids content, the water-soluble starch can be present in an amount of about 10 - 65 wt.%, about 15 - 65 wt.%, about 20 - 60 wt.%, about 25 - 60 wt.%, about 30 - 55 wt.%, about 30 - 50 wt.% or about 30 - 45 wt.%.

[0072] The water-soluble starch can include unmodified starch, starch modified with non-ionic groups, starch modified with anionic groups, and / or starch modified with cationic groups.

[0073] The water-soluble starch can include starch modified with cationic groups, and the degree of modification is optionally in the range of about 0.01 - 10 mol.%, about 0.1 - 5 mol.%, about 0.1 - 3 mol.%, about 0.1 - 2 mol.%, about 0.1 - 1 mol.% or about 0.1 - 0.5 mol.%.

[0074] The starch modified with cationic groups can include, for example, starch modified with cationic quaternary ammonium groups having the structure of formula A, where R1, R2, and R3 are each independently H or C1-C 10 alkyl or C1-C 10 hydroxyalkyl, and R4 is a straight-chain or branched C1-C 10 alkylene or C1-C 10 hydroxyalkylene, optionally substituted by one or more heteroatom-containing groups, and where X is an ether or ester bond connecting R4 to the starch, or a hydrocarbon group containing oxygen, nitrogen, or sulfur.

[0075]

[0076] R1, R2, and R3 can be the same C1-C4 alkyl groups, and R4 can be a C1-C6 hydroxyalkylene group. Alternatively, R4 can be a C3-C6 hydroxyalkylene group. Alternatively, R1, R2, and R3 can each be a methyl group, and R4 can be a C3-C6 hydroxyalkylene group.

[0077] The cationic quaternary ammonium group can be a quaternary 2-hydroxy-3-(trimethylammonium)propyl group, 2-diethylaminoethyl group, 2,3-epoxypropyltrimethylammonium group, or a combination thereof.

[0078] The starch modified with the cationic group can include starch modified with a cationic trimethylammonium group. The starch modified with the cationic group can include starch modified with a cationic trimethylammonium salt.

[0079] The starch modified with the cationic group can include starch modified with: a 2-diethylaminoethyl salt, a 2,3-epoxypropyltrimethylammonium salt, or a 2-hydroxy-3-(trimethylammonium)propyl salt, or a combination thereof.

[0080] The 2-diethylaminoethyl salt can include 2-diethylaminoethyl halide, the 2,3-epoxypropyltrimethylammonium salt can include 2,3-epoxypropyltrimethylammonium halide, and the 2-hydroxy-3-(trimethylammonium)propyl salt can include 2-hydroxy-3-(trimethylammonium)propyl halide.

[0081] The 2-diethylaminoethyl salt can include 2-diethylaminoethyl chloride, the 2,3-epoxypropyltrimethylammonium salt can include 2,3-epoxypropyltrimethylammonium chloride, and the 2-hydroxy-3-(trimethylammonium)propyl salt can include 2-hydroxy-3-(trimethylammonium)propyl chloride.

[0082] The water-soluble starch can include a combination of the starch modified with the cationic group and unmodified starch.

[0083] The polyvinyl alcohol (PVOH) can include unmodified polyvinyl alcohol, polyvinyl alcohol modified with a nonionic group, polyvinyl alcohol modified with an anionic group, polyvinyl alcohol modified with a cationic group, or a combination thereof.

[0084] The polyvinyl alcohol can include polyvinyl alcohol modified with an anionic group, with a modification degree of about 0.1-10 mol.%, about 0.5-8 mol.%, about 1-6 mol.%, about 1-5 mol.%, about 1_4 mol.%, or about 1-3.5 mol.%.

[0085] The anion group-modified polyvinyl alcohol may include polyvinyl alcohol modified with one or more groups derived from itaconic acid, monomethyl maleate (MMM), methyl acrylate (MA), aminopropyl sulfonate, maleic acid, maleic anhydride, vinyl pyrrolidone, n-vinyl pyrrolidone, n-vinyl caprolactam, derivatives of any of the foregoing, or combinations thereof.

[0086] The anion group-modified polyvinyl alcohol may include polyvinyl alcohol modified with monomethyl maleate, methyl acrylate, or a combination thereof.

[0087] The aqueous solution may further include a plasticizer, which is present in a range of about 5-40 wt.% based on the weight of the total solids content.

[0088] The plasticizer may include sorbitol, glycerol, glycerin, diglycerol, propylene glycol, dipropylene glycol, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol with a molecular weight of up to 400, 2-methyl-1,3-propanediol, ethanolamine, trimethylolpropane (TMP), polyether polyol, isomaltitol, maltitol, xylitol, erythritol, adonitol, galactitol, pentaerythritol, mannitol, sugar alcohol, or combinations thereof. The plasticizer may not include trimethylolpropane (TMP).

[0089] The plasticizer may include a bio-based plasticizer. The bio-based plasticizer may include glycerol and / or sorbitol.

[0090] The aqueous solution may further include a surfactant.

[0091] The surfactant may include a linear aliphatic ethoxylated surfactant. The linear aliphatic ethoxylated surfactant may include laureth-6 formate, C9-C 15 ethylene oxide, or combinations thereof.

[0092] The aqueous solution may further include at least one auxiliary agent from the following groups: defoamer, antioxidant, disinfectant, anti-blocking agent, filler, sodium metabisulfite, sodium hydroxide, matting agent, slip agent, dispersant, or combinations thereof.

[0093] The weight ratio of polyvinyl alcohol to water-soluble starch may be in the range of about 10:1 to about 1:8, about 9:1 to about 1:7, about 6:1 to about 1:6, or about 5:1 to about 1:6.

[0094] Another aspect of the present disclosure provides a method for forming a water-soluble film of the present disclosure, the method including: casting the aqueous solution of the present disclosure onto a substrate with a specified thickness; and drying the water in the cast aqueous solution to form the water-soluble film.

[0095] Another aspect of the present disclosure provides an article comprising a pouch or sachet made of the water-soluble film of the present disclosure and defining an internal pouch volume.

[0096] The article may further comprise a consumer product or chemical composition contained in the internal pouch volume and encapsulated within the sachet. The chemical composition may be a household care composition. The household care composition may be a laundry detergent or dishwashing detergent in liquid or solid form (e.g., liquid form).

[0097] The compression strength of the sachet may be at least about 300 N, at least about 600 N, at least about 800 N, or at least about 1000 N.

[0098] The sachet may have a matte-to-matte type, matte-to-gloss type, or gloss-to-gloss type seal, such as a matte-to-matte type seal.

[0099] According to the liquid release test described herein, at a temperature of about 20°C, after the sachet is mixed in water, the release time of the chemical composition of the sachet may not exceed 300 seconds. According to the liquid release test described herein, at about 20°C, or alternatively at a temperature of about 5°C or about 15°C, after the sachet is mixed in water, the release time may be in the range of about 30 - 300 seconds, about 30 - 200 seconds, or about 30 - 150 seconds.

[0100] Water-soluble film

[0101] The present disclosure provides a water-soluble film comprising a high loading level of a water-soluble polymer and a bio-based polysaccharide. Such a film may have desired physical properties. The bio-based polysaccharide may comprise homopolysaccharides and heteropolysaccharides. The bio-based polysaccharide may include starch, glycogen, galactogen, inulin, cellulose, chitin, hyaluronic acid, heparin, chondroitin 4-sulfate, gamma globulin, or a combination thereof. The bio-based polysaccharide may be a water-soluble bio-based polysaccharide. The water-soluble bio-based polysaccharide may comprise water-soluble starch. The water-soluble starch may be present in the following amounts by weight of the water-soluble film: about 5 - 65 wt.%, about 10 - 65 wt.%, about 10 - 60 wt.%, about 15 - 60 wt.%, about 20 - 60 wt.%, about 20 - 55 wt.%, about 20 - 50 wt.%, or about 25 - 45 wt.%.

[0102] As used herein, and unless otherwise specified, the term "water-soluble film" refers to a film that dissolves in a time of 300 seconds or less at a temperature of about 40 °C according to the MSTM-205 standard set forth herein. For example, at a temperature of about 80 °C, about 70 °C, about 60 °C, about 50 °C, about 40 °C, about 20 °C, about 10 °C, or about 5 °C, the dissolution time can optionally be 200 seconds or less, 100 seconds or less, 60 seconds or less, or 30 seconds or less. As used herein, and unless otherwise specified, the term "cold water soluble" refers to any film that has a dissolution time of 300 seconds or less at 10 °C as determined according to MSTM-205. For example, at 10 °C, the dissolution time can optionally be 200 seconds or less, 100 seconds or less, 60 seconds or less, or 30 seconds. At a temperature of 80 °C, a "water-soluble film" with a thickness of 1.5 mil can dissolve in 300 seconds or less. Optionally, at a temperature of about 70 °C, about 60 °C, about 50 °C, about 40 °C, about 30 °C, about 20 °C, about 10 °C, or about 5 °C, the dissolution time of a water-soluble film with a thickness of 1.5 mil (about 38 μm) can be 300 seconds or less, 200 seconds or less, 100 seconds or less, 60 seconds or less, 30 seconds or less, or 20 seconds or less.

[0103] As used herein, the term "water-soluble starch" refers to a starch that has a gelatinization percentage of at least about 5 wt.%, such as at least about 6 wt.%, or at least about 7 wt.%, or at least about 8 wt.%, or at least about 9 wt.%, or at least about 10 wt.%, or at least about 11 wt.%, or at least about 12 wt.%, or at least about 13 wt.%, or at least about 14 wt.%, or at least about 15 wt.%, or at least about 16 wt.%, or at least about 17 wt.%, or at least about 18 wt.%, or at least about 19 wt.%, or at least about 20 wt.%. The starch must first be gelatinized in water before it can dissolve in water. Gelatinization refers to the swelling of starch granules by water and the breaking of the intermolecular bonds of starch molecules under the action of heat, thereby destroying the semi-crystalline regions of the starch. The inventors have surprisingly found that starches with a unique combination of low molecular weight, lower amylose content, and / or the chemical modifications disclosed herein are more easily gelatinized and dissolved in water to achieve a gelatinization percentage of at least about 5 wt.%, about 10 wt.%, or about 15 wt.% after heating and mixing in water at about 95 °C for about 30 minutes, and can produce useful solutions for forming water-soluble films and related useful water-soluble films and articles made therefrom.

[0104] The water-soluble starch can be substantially gelatinized starch in the water-soluble film.

[0105] Water-soluble starch can include water-soluble unmodified starch, water-soluble modified starch, or a combination thereof. Water-soluble unmodified starch can include naturally-derived polysaccharides composed of anhydroglucose units with 1-4α and 1-6α glycosidic bonds, forming linear or branched chains. The linear chains are called amylose, and the branched chains are called amylopectin. Generally, starches with lower molecular weight and lower amylose content are more easily gelatinized and soluble in water. Water-soluble unmodified starch can include starches without chemical moieties added to the polysaccharide. For example, unmodified starch can include starches with reduced molecular weight by techniques such as acid hydrolysis.

[0106] Water-soluble modified starch can include physically modified starch, enzymatically modified starch, and chemically modified starch. Chemically modified starch can include chemically decomposed starch, such as acid-treated starch, hypochlorite-oxidized starch, or dimethyl ether starch; and starch modified with non-ionic groups, including esterified starch and etherified starch; and / or starch modified with ionic groups, including anionically modified starch and cationically modified starch. Water-soluble starch can include starches disclosed herein having one or more of the following characteristics, whether unmodified or modified starch, including desired molecular weight, amylose-to-amylopectin ratio, and type and level of modification, to achieve at least about 5 wt.%, or about 10 wt.% or at least about 15 wt.% cooked % under batch cooking conditions (heating and mixing in water at about 95 °C for about 30 minutes).

[0107] The molecular weight, amylose / amylopectin ratio, and type and degree of modification of starch can significantly affect the cooked % (i.e., the maximum weight percentage of starch dissolved in water after heating and mixing in water at 95 °C for 30 minutes, commonly referred to as cooked % in the starch industry), the rheology of the resulting starch solution, and additional interactions and miscibility with polyvinyl alcohol. The cooked % of unmodified starch directly extracted from plants is typically only 1-2%. Starch molecular weight can be reduced by acid hydrolysis, which increases the maximum cooked %. Certain types of chemical modification of starch can increase the cooked %, inhibit retrogradation, and reduce the viscosity of the starch solution. Chemical modification is typically targeted at the 2nd and 3rd carbons of the glucose unit and is achieved by reaction with the secondary alcohol at these sites. Chemical modification includes examples of non-ionic (e.g., hydroxyethyl, hydroxypropyl), anionic (e.g., carboxyl), and cationic (e.g., trimethylammonium) modification of starch.

[0108] The water-soluble starch of the present disclosure can have a desired combination of low molecular weight, amylose / amylopectin ratio, and type and level of modification. The gelatinization % can be at least about 5 wt.%, at least about 10 wt.%, at least about 15 wt.%, at least about 16 wt.%, at least about 17 wt.%, at least about 18 wt.%, at least about 19 wt.%, at least about 20 wt.% or even 25 wt.%, and can have good miscibility with the PVOH of the present disclosure in an aqueous PVOH-based film-forming solution and will not phase-separate from the PVOH. The total solids content of the film-forming solution is in the range of about 5 - 50 wt.%, about 10 - 40 wt.%, about 15 - 35 wt.%, about 20 - 35 wt.%, about 25 - 35 wt.%, about 25 - 32 wt.% or even about 32 - 35 wt.%.

[0109] The water-soluble modified starch can include physically modified starch, such as discrete amylose or amylopectin, or heat-moisture treated starch; enzymatically modified starch, such as hydrolyzed dextrin, enzymatically degraded dextrin or amylose; and / or chemically degraded starch, such as acid-treated starch, hypochlorite oxidized starch or dimethylformamide starch.

[0110] The water-soluble modified starch can include chemically modified starch, including: starch modified with non-ionic groups, such as esterified starch and etherified starch; and / or starch modified with ionic groups, such as starch modified with anionic groups and starch modified with cationic groups. Esterified starch can include acetic acid esterified starch, succinic acid esterified starch, nitric acid esterified starch, phosphoric acid esterified starch, urea-phosphoric acid esterified starch, xanthic acid esterified starch, acetoacetic acid esterified starch, etc. Etherified starch can include allyl etherified starch, methyl etherified starch, carboxymethyl etherified starch, hydroxyethyl etherified starch, hydroxypropyl etherified starch, etc. Non-limiting examples of starch modified with non-ionic groups can include starch modified with hydroxyethyl or hydroxypropyl.

[0111] The water-soluble modified starch can include starch modified with ionic groups, including starch modified with cationic groups or starch modified with anionic groups. The modified starch can include starch modified with anionic groups. Non-limiting examples of starch modified with anionic groups can include starch modified with carboxyl groups.

[0112] The modified starch can include starch modified with cationic groups. The starch modified with cationic groups can include starch modified with cationic amine or ammonium groups, including starch modified with primary amine groups, secondary amine groups, tertiary amine groups, or quaternary amine or ammonium groups. The starch modified with cationic groups can include starch modified with quaternary ammonium groups. Non-limiting examples of the starch modified with quaternary ammonium groups can include starch modified with trimethylammonium groups, starch modified with 2-diethylaminoethyl halide salts, starch modified with 2,3-epoxypropyltrimethylammonium halide salts, etc.

[0113] The modified starch can include chemically modified starch, and the degree of modification of the starch can be in the range of about 0.01 - 10 mol.%, about 0.05 - 5 mol.%, about 0.05_4 mol.%, about 0.05 - 3 mol.%, about 0.05 - 2 mol.%, about 0.05 - 1 mol.%, about 0.1 - 1 mol.%, about 0.1 - 0.5 mol.%, about 0.1 - 0.3 mol.%, about 0.05 - 3.5 mol.%, about 1.0 - 5.0 mol.% or about 1 - 3.5 mol.%, for example, about 0.18 mol.% or 0.21 mol.

[0114] The modified starch can include starch modified with cationic groups, and the degree of modification of the starch can be in the range of about 0.01 - 10 mol.%, about 0.05 - 5 mol.%, about 0.05_4 mol.%, 0.05 - 3.5 mol.%, about 0.05 - 3 mol.%, about 0.05 - 2 mol.%, about 0.05 - 1 mol.%, about 0.1 - 1 mol.%, about 0.1 - 0.5 mol.% or about 0.1 - 0.3 mol.

[0115] Based on the weight of the dry water-soluble film, the loading level of the water-soluble starch in the water-soluble film can be relatively high, for example, at least about 5 wt.%, about 10 wt.%, about 15 wt.%, about 20 wt.%, about 25 wt.%, about 30 wt.%, about 35 wt.%, about 40 wt.%, about 45 wt.%, about 50 wt.%, about 55 wt.%, about 60 wt.%, about 65 wt.%, or even higher than about 65 wt.%, or in the range of about 5 - 70 wt.%, about 10 - 65 wt.%, about 10 - 60 wt.%, about 15 - 60 wt.%, about 20 - 55 wt.%, about 25 - 50 wt.% or about 25_45 wt.

[0116] Even when the loading level of the water-soluble starch is high, the water-soluble film can still exhibit desired physical properties for use in sachets and packets for packaging liquid detergent compositions.

[0117] The water-soluble film may further comprise one or more plasticizers, optionally at least one of which is a bio-based plasticizer. The water-soluble film may have a relatively high renewable carbon index (RCI), which is higher than about 50%. The water-soluble film may further comprise one or more of the following: disinfectants, antioxidants or preservatives, defoamers or antifoaming agents, surfactants, anti-blocking agents, fillers, and matting agents.

[0118] The renewable carbon index (RCI) of the water-soluble film may be higher than about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, or even about 85%, or in the range of about 30 - 85%, 40 - 75%, 45 - 70%, about 50 - 75%, or about 50 - 70%. The water-soluble film may comprise a bio-based plasticizer.

[0119] According to the accelerated quantitative residue evaluation test method described herein, the water-soluble film can dissolve in water at a temperature of about 15°C, wherein the residue (undissolved film), by weight of the water-soluble film, does not exceed about 10 wt.%, for example, does not exceed about 9 wt.%, 8 wt.%, 7 wt.%, 6 wt.%, 5.5 wt.%, 5 wt.%, 4.5 wt.%, 4 wt.%, 3.5 wt.%, 3 wt.%, 2.5 wt.%, 2 wt.%, 1.5 wt.%, 1 wt.%, or 0.5 wt.%, or even 0 wt.% (completely dissolved, no undissolved film). At a temperature of about 90°C, about 80°C, about 70°C, about 60°C, about 50°C, about 40°C, about 30°C, about 20°C, about 10°C, or about 5°C, by weight of the film, the residue of the water-soluble film may not exceed about 7 wt.%, not exceed about 6.0 wt.%, not exceed about 5.0 wt.%, not exceed about 4.0 wt.%, not exceed about 3.0 wt.%, or not exceed about 3.5 wt.%. The water-soluble film, at a temperature in the range of about 5 - 95°C, at a cold water temperature of about 5°C or about 10°C, or at about room temperature, by weight of the film, the residue does not exceed about 5.0 wt.% of the film.

[0120] Water-soluble polyvinyl alcohol (PVOH)

[0121] The water-soluble polymer may include, but is not limited to, polyvinyl alcohol (PVOH), polyacrylamide, poly(acrylic acid), poly(methacrylic acid), polyvinylpyrrolidone, polyacrylate, water-soluble acrylate copolymer, vinylpyrrolidone-modified PVOH, polyethyleneimine, pullulan, cellulose ether, the foregoing copolymers, and any combination of any of the foregoing. Such water-soluble polymers, whether PVOH or others, are commercially available from various sources.

[0122] The water-soluble polymer is or can comprise water-soluble polyvinyl alcohol (PVOH).

[0123] As used herein and unless otherwise specified, the term "water-soluble polyvinyl alcohol" refers to polyvinyl alcohol that is soluble in water at a temperature of about 60 °C within about 60 minutes, about 50 minutes, about 40 minutes, about 30 minutes, about 20 minutes, about 10 minutes, about 5 minutes, or about 3 minutes. The water-soluble polyvinyl alcohol can be soluble in water at a temperature of about 40 °C within about 60 minutes, about 50 minutes, about 40 minutes, about 30 minutes, about 20 minutes, about 10 minutes, about 5 minutes, or about 3 minutes. The water-soluble polyvinyl alcohol can be soluble in cold water at a temperature of about room temperature within about 60 minutes, about 50 minutes, about 40 minutes, about 30 minutes, about 20 °C, about 10 minutes, about 5 minutes, or about 3 minutes. The water-soluble polyvinyl alcohol can be soluble in cold water at a temperature of about 10 °C within about 60 minutes, about 50 minutes, about 40 minutes, about 30 minutes, about 20 minutes, about 10 minutes, about 5 minutes, or about 3 minutes.

[0124] The water-soluble polyvinyl alcohol in the films of the present disclosure can include bio-based polyvinyl alcohol. Bio-based polyvinyl alcohol includes polyvinyl alcohol in which at least a portion of the carbon comprising the polyvinyl alcohol is derived from biomass. Specifically, bio-based polyvinyl alcohol can include polyvinyl alcohol produced by hydrolyzing or saponifying a bio-based polyvinyl acetate or a blend of polyvinyl acetates including a bio-based polyvinyl acetate. Further, the bio-based polyvinyl acetate can include polyvinyl acetate produced by polymerizing a bio-based vinyl acetate or a blend of vinyl acetates including a bio-based vinyl acetate. Generally, bio-based vinyl acetate includes vinyl acetate in which at least a portion of the carbon comprising the vinyl acetate is derived from biomass. For example, vinyl acetate can be obtained by the gas-phase reaction of ethylene, acetic acid, and oxygen; bio-based vinyl acetate can refer to vinyl acetate in which at least a portion of the ethylene and / or acetic acid is derived from biomass. For example, bio-based vinyl acetate includes vinyl acetate obtained by the reaction of ethylene, acetic acid, and oxygen, in which at least a portion of the ethylene and / or at least a portion of the acetic acid is bio-based. Thus, bio-based polyvinyl alcohol includes polyvinyl alcohol in which a portion of the carbon comprising the polyvinyl alcohol is from bio-based ethylene and / or bio-based acetic acid.

[0125] Plants that can be sources of bio-based ethylene and / or bio-based acetic acid include, but are not limited to, potatoes, sweet potatoes, sugar beets, rice, wheat, palm oil, algae, corn, sugar cane, sorghum, and cassava. Similarly, bio-based acetic acid can also be produced via the bioethanol route.

[0126] Bio-based polyvinyl alcohol can be characterized by its carbon-14 ( 14 C) content. Generally, relative to petroleum-derived resources 14C abundance, of biomass-derived resources 14 The C abundance (i.e., 14 the percentage of the amount of C in the total carbon content) is higher. Specifically, relative to the 14 C abundance of petroleum-derived ethylene and acetic acid, the 14 C abundance of bio-based ethylene and acetic acid is generally higher, and further, relative to the 14 C abundance of fully petroleum-derived polyvinyl alcohol, the 14 C abundance of bio-based polyvinyl alcohol is generally higher. Thus, the abundance of 14 C in a polymer (such as a polyvinyl alcohol resin) can serve as a marker of the bio-based content of the polymer. The 14 C content of the material can be measured by known methods, such as by mass spectrometry.

[0127] The membranes of the present disclosure can include bio-based polyvinyl alcohol, as described in U.S. Patent Application Publication No. 2023 / 0257491A1, U.S. Patent Application Publication No. 2023 / 0070770A1, and International Patent Application Publication WO 2022 / 034906A1, the entire contents of which are hereby incorporated by reference in their entirety. The polyvinyl alcohol resin comprising the membranes of the present disclosure can comprise only petroleum-derived polyvinyl alcohol, or only bio-based polyvinyl alcohol, or a blend of petroleum-derived polyvinyl alcohol and bio-based polyvinyl alcohol. For membranes comprising a blend of petroleum-derived (i.e., non-bio-based) polyvinyl alcohol and bio-based polyvinyl alcohol, the ratio (by weight) of the amount of bio-based polyvinyl alcohol to non-bio-based polyvinyl alcohol is not particularly limited and can be, for example, in the range of about 99:1 to about 1:99, or about 95:5 to about 5:99, or about 80:20 to about 20:80, or about 70:30 to about 30:70, or about 60:40 to about 40:60.

[0128] Typically, polyvinyl alcohol may generally be chemically incompatible with starch. However, the inventors have found that by selectively controlling one or more aspects of the membrane and the film-forming solution, such as the properties of water-soluble PVOH and water-soluble starch, the type of plasticizer and other membrane components, the relative amounts between the membrane components, and the process for preparing the water-soluble membrane, phase separation between water-soluble polyvinyl alcohol (PVOH) and water-soluble starch can be eliminated or minimized.

[0129] The present inventors surprisingly found that by selectively using a combination of a water-soluble polymer modified with ionic groups (such as polyvinyl alcohol (PVOH) modified with ionic groups) and starch modified with ionic groups to prepare a water-soluble film, even in the case of a high solid content and / or a high loading level of starch, the phase separation problem of water-soluble PVOH and water-soluble starch in the final water-soluble film and / or the aqueous film-forming solution during the preparation process can be completely eliminated or minimized as needed. For example, a combination of polyvinyl alcohol (PVOH) modified with anionic groups and starch modified with cationic groups can be used, and the resulting water-soluble film has no phase separation problem in both the water-soluble film and the aqueous solution forming the water-soluble film. The PVOH modified with anionic groups and the starch modified with cationic groups are characterized by a single glass transition temperature (Tg) measured by differential scanning calorimetry (DSC) tests shown in Table 11 of Example 7. On the other hand, a combination of polyvinyl alcohol (PVOH) modified with cationic groups and starch modified with anionic groups can be used to prepare a water-soluble film without any phase separation problem.

[0130] The water-soluble polymer may comprise a polyvinyl alcohol (PVOH) resin, which is present in an amount of about 10 wt.% to about 95 wt.%, about 20 wt.% to about 95 wt.%, about 25 wt.% to about 85 wt.%, about 30 wt.% to about 75 wt.%, about 30 wt.% to about 65 wt.%, about 30 wt.% to about 55 wt.%, about 30 wt.% to about 50 wt.%, about 35 wt.% to about 45 wt.% or about 35 wt.% to about 55 wt.% based on the total weight of the water-soluble film.

[0131] The polyvinyl alcohol (PVOH) resin may include a modified polyvinyl alcohol (PVOH) resin and / or an unmodified polyvinyl alcohol (PVOH) resin. The water-soluble polymer may comprise a modified PVOH, which includes a polyvinyl alcohol (PVOH) resin modified with anionic groups or a polyvinyl alcohol (PVOH) resin modified with cationic groups.

[0132] The modified (PVOH) can include an anion group-modified polyvinyl alcohol (PVOH) resin selected from the group consisting of itaconic acid, monomethyl maleate (MMM), maleic anhydride, methyl acrylate (MA), aminopropyl sulfonate, maleic acid, N-vinylpyrrolidone, N-vinylcaprolactam, derivatives of any of the foregoing, or combinations of any of the foregoing. The degree of modification of the PVOH can be about 0.01 - 10 mol.%, about 0.05 - 9 mol.%, about 0.1 - 8 mol.%, about 0.2 - 7 mol.%, about 0.3 - 6 mol.%, about 0.4 - 5 mol.%, about 0.5 - 5 mol.%, about 1 - 5 mol.%, about 1 - 4 mol.%, or about 1 - 3.5 mol.%. Based on the total weight of the water-soluble film, the modified PVOH can be present in the water-soluble film in the following amounts: about 10 - 95 wt.%, about 15 - 95 wt.%, about 20 - 85 wt.%, about 25 - 75 wt.%, about 30 - 65 wt.%, about 30 - 55 wt.%, about 35 - 55 wt.%, or about 30 - 50 wt.%.

[0133] Polyvinyl alcohol is a synthetic polymer, typically prepared by the alcoholysis (commonly referred to as hydrolysis or saponification) of polyvinyl acetate. In the case where almost all acetate groups have been converted to alcohol groups, fully hydrolyzed PVOH is a strongly hydrogen-bonded, highly crystalline polymer that is only soluble in hot water at temperatures greater than about 140°F (about 60°C). If a sufficient number of acetate groups are allowed to remain after the hydrolysis of polyvinyl acetate, i.e., the PVOH polymer is partially hydrolyzed, the polymer has weaker hydrogen bonding, lower crystallinity, and is generally soluble in cold water at temperatures below about 50°F (about 10°C). Thus, the partially hydrolyzed polymer is an ethylene alcohol-vinyl acetate copolymer, which is a PVOH copolymer but is commonly referred to as homopolymer PVOH or unmodified polyvinyl alcohol (PVOH). As used herein, the term "unmodified polyvinyl alcohol" refers to PVOH, which is a fully or partially hydrolyzed polyvinyl acetate and has vinyl alcohol monomer units and optionally vinyl acetate monomer units (when partially hydrolyzed), without any third monomer units.

[0134] Polyvinyl alcohol includes modified polyvinyl alcohol, such as copolymers. As used herein, the term "modified polyvinyl alcohol" refers to a polyvinyl alcohol resin chemically modified by chemical groups and may include copolymers or higher polymers (e.g., terpolymers) that include one or more monomers in addition to vinyl acetate / vinyl alcohol groups. The modification can be neutral, such as provided by ethylene, propylene, N-vinylpyrrolidone, or other uncharged monomer species. In other aspects, the modification can be cationic modification, such as provided by a positively charged monomer species. In other aspects, the modification can be anionic modification, such as provided by a negatively charged monomer species.

[0135] The pyrrolidone comonomer can include a compound having a polymerizable carbon-carbon double bond and a pyrrolidone ring substituent represented by the following formula:

[0136]

[0137] wherein R1, R2, R3, R4, R5, and R6 are each independently selected from a hydrogen atom or an alkyl group, such as an alkyl group having 1 to 8 carbon atoms. Examples of the group represented by the general formula (I) are 2-oxopyrrolidin-1-yl, 3-propyl-2-oxopyrrolidin-1-yl, 5-methyl-2-oxopyrrolidin-1-yl, 5,5-dimethyl-2-oxopyrrolidin-1-yl, 3,5-dimethyl-2-oxopyrrolidin-1-yl, and the like. The carbon-carbon double bond contained in the pyrrolidone comonomer can include vinyl, allyl, styryl, acryloxy, methacryloxy, vinyloxy, allyloxy, and other groups copolymerizable with the vinyl ester of the above fatty acid, and has high alkali resistance when the copolymer is hydrolyzed to form a vinyl alcohol copolymer. Examples of the pyrrolidone comonomer can include N-vinyl-2-pyrrolidone, N-vinyl-3-propyl-2-pyrrolidone, N-vinyl-5-methyl-2-pyrrolidone, N-vinyl-5,5-dimethyl-2-pyrrolidone, N-vinyl-3,5-dimethyl-2-pyrrolidone, N-allyl-2-pyrrolidone, and the like.

[0138] As used herein, the term "cationic group-modified polyvinyl alcohol" refers to a polyvinyl alcohol resin chemically modified by a cationic group and may include a partially or fully hydrolyzed PVOH copolymer that includes cationic monomer units, vinyl alcohol monomer units, and optionally vinyl acetate monomer units (i.e., when not fully hydrolyzed). Examples of cationic polyvinyl alcohol include glycidyl-trimethylammonium chloride-modified polyvinyl alcohol, and those derived from cationic monomers of acrylamide and methacrylamide derivatives, such as N-(1,1-dimethyl-dimethylaminopropyl)acrylamide and N-(dimethylaminopropyl)methacrylamide and their quaternary ammonium salts.

[0139] Polyvinyl alcohol (PVOH) resins may include anion-modified polyvinyl alcohol. As used herein, the term "anion-group-modified polyvinyl alcohol" or "anion-modified polyvinyl alcohol" refers to a polyvinyl alcohol resin chemically modified by an anion group and may include a partially or fully hydrolyzed PVOH copolymer comprising anionic monomer units, vinyl alcohol monomer units, and optionally vinyl acetate monomer units (i.e., when not fully hydrolyzed). The PVOH copolymer may include two or more types of anionic monomer units. General classes of anionic monomer units that may be used in the PVOH copolymer include vinyl polymerization units corresponding to vinyl sulfonic acid monomers and their esters, monocarboxylic acid vinyl monomers, their esters and anhydrides, dicarboxylic acid monomers having a polymerizable double bond, their esters and anhydrides, and alkali metal salts of any of the foregoing. Examples of suitable anionic monomer units include vinyl polymerization units corresponding to vinyl anionic monomers, which include vinyl acetic acid, maleic acid, monoalkyl maleate, dialkyl maleate, monomethyl maleate (MMM), maleic anhydride, dimethyl maleate, methyl acrylate (MA), fumaric acid, monoalkyl fumarate, dialkyl fumarate, monomethyl fumarate, dimethyl fumarate, itaconic acid, monoalkyl itaconate, dialkyl itaconate, monomethyl itaconate, dimethyl itaconate, itaconic anhydride, carboxylic acid, aminopropyl sulfonate, n-vinyl pyrrolidone, n-vinyl-caprolactam, citraconic acid, monoalkyl citraconate, dialkyl citraconate, citraconic anhydride, mesaconic acid, monoalkyl mesaconate, dialkyl mesaconate, glutaconic acid, monoalkyl glutaconate, dialkyl glutaconate, glutaconic anhydride, alkyl acrylate, (alkyl) acrylate, vinyl sulfonic acid, allyl sulfonic acid, ethene sulfonic acid, 2-acrylamido-1-methylpropanesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 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 C1-C4 or C6 alkyl esters), and combinations of the foregoing (e.g., multiple types of anionic monomers or equivalent forms of the same anionic monomer).

[0140] Polyvinyl alcohol (PVOH) can be modified with one or more anionic groups selected from the following: maleic acid, monoalkyl maleate, dialkyl maleate, monomethyl maleate (MMM), maleic anhydride, dimethyl maleate, methyl acrylate (MA), alkali metal salts of any of the foregoing, esters of any of the foregoing, and combinations of any of the foregoing. Polyvinyl alcohol can be modified with anionic groups consisting of the following: maleic acid, monomethyl maleate, dimethyl maleate, maleic anhydride, alkali metal salts of any of the foregoing, esters of any of the foregoing, and combinations of any of the foregoing. The anionic monomer can include one or more of monomethyl maleate and its alkali metal salts (e.g., sodium salt).

[0141] The PVOH copolymer can include two or more types of monomer units selected from neutral, anionic, and cationic monomer units.

[0142] The incorporation level of one or more anionic monomer units in the PVOH copolymer can be in the range of about 0.1 mol.% to about 10 mol.% or about 1 mol.% to about 5 mol.%. (For example, at least about 0.1, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, or 4.0 mol.% and / or at most about 3.0, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.5, 9.0, 9.5, or 10 mol.%).

[0143] The anionic group - modified polyvinyl alcohol can include at least about 0.5 mol.% of modification. The anionic group - modified polyvinyl alcohol can include about 1.0 mol.% to about 5.0 mol.% of modification. The anionic group - modified polyvinyl alcohol can include about 1.0 mol.% to about 3.5 mol.% of modification.

[0144] Based on the weight of the water-soluble film, the amount of the anion group-modified PVOH resin present in the water-soluble film can be at least about 10 wt.%, about 15 wt.%, about 20 wt.%, about 25 wt.%, about 30 wt.%, about 35 wt.%, about 40 wt.%, about 45 wt.%, about 50 wt.%, about 55 wt.%, about 60 wt.%, about 65 wt.%, about 70 wt.%, about 75 wt.%, about 80 wt.%, about 85 wt.% or about 90 wt.% and / or at most about 60 wt.%, about 70 wt.%, about 80 wt.%, about 90 wt.%, about 95 wt.% or about 99 wt.%. Based on the weight of the water-soluble film, the amount of the anion group-modified PVOH resin that can be present in the water-soluble film is in the range of about 10 - 80 wt.%, about 15 - 75 wt.%, about 20 - 70 wt.%, about 25 - 65 wt.%, about 30 - 55 wt.%, about 30 - 50 wt.% or about 30 - 45 wt.%.

[0145] When unmodified PVOH or anion group-modified PVOH is present, the degree of hydrolysis (D.H. or DH) of the total PVOH resin content of the water-soluble film can be about 60 mol.%, at least about 70 mol.%, about 74 mol.%, about 80 mol.%, about 84 mol.%, about 85 mol.%, about 88 mol.%, about 90 mol.%, about 91 mol.% or about 94 mol.% and at most about 99 mol.%, about 98 mol.%, about 96 mol.%, about 95 mol.%, about 94 mol.%, about 93 mol.%, about 92 mol.% or about 91 mol.%, for example, in the range of about 74 mol.% to about 99 mol.% or about 74 mol.% to about 91 mol.%. As used herein, the degree of hydrolysis is expressed as the mole percentage of vinyl acetate units converted to vinyl alcohol units. The degree of hydrolysis of PVOH can be at least about 74 mol%. The degree of hydrolysis of PVOH can be at most 99 mol%. The degree of hydrolysis of PVOH can be at most about 91 mol%. The degree of hydrolysis of PVOH can be in the range of about 74 - 99 mol.% or about 74 - 91 mol.%.

[0146] The solubility characteristics of polyvinyl alcohol may change. Those skilled in the art know that the acetate groups in copolymers (PVOH homopolymers) of vinyl acetate and vinyl alcohol can be hydrolyzed by acid or base hydrolysis. As the degree of hydrolysis increases, the polymer composition made from PVOH homopolymers will have increased mechanical strength and decreased solubility at lower temperatures (e.g., hot water temperature is required for complete dissolution). Therefore, exposing PVOH homopolymers to an alkaline environment (e.g., generated by laundry bleach additives) 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, which may result in undissolved polymer residues at the end of the wash cycle.

[0147] PVOH copolymers with side carboxyl groups, such as vinyl alcohol / sodium hydrolyzed methyl acrylate (MA) polymers, can form lactone rings between adjacent side carboxyl groups and alcohol groups, thereby reducing the water solubility of the PVOH copolymer. In the presence of strong base, the lactone ring can open over the course of several weeks under relatively warm (ambient) and high humidity conditions (e.g., by lactone ring opening reaction to form the corresponding side carboxyl group and alcohol group, while water solubility increases). Therefore, contrary to the effects observed in the case of PVOH homopolymers, it is believed that due to the chemical interaction between the polymer and the alkaline composition within the sachet during storage, such PVOH copolymers can become more soluble. Thus, as they age, the sachets may become increasingly prone to premature dissolution during a hot wash cycle (nominal 40 °C), and due to the presence of bleach and the resulting decrease in pH, the efficacy of certain laundry actives may be reduced.

[0148] Certain sulfonic acids and their derivatives with polymerizable vinyl bonds can be copolymerized with vinyl acetate to provide stable cold-water-soluble PVOH polymers in the presence of strong base. The base-catalyzed alcoholysis products of these copolymers are used to formulate water-soluble films and are rapidly dissolving vinyl alcohol sulfonate copolymers. The sulfonate groups in the PVOH copolymer can revert to sulfonic acid groups in the presence of hydrogen ions, but the sulfonic acid groups still provide excellent cold-water solubility to the polymer. Optionally, the vinyl alcohol - sulfonate copolymer can be free of residual acetate groups (i.e., completely hydrolyzed) and thus cannot be further hydrolyzed by acid or base hydrolysis.

[0149] Typically, as the amount of modification increases, water solubility also increases. Thus, sufficient modification with sulfonate esters or sulfonic acid groups inhibits hydrogen bonding and crystallinity, enabling dissolution in cold water. In the presence of acidic or basic species, the copolymer is generally unaffected, except for sulfonate esters or sulfonic acid groups, which maintain excellent cold water solubility even in the presence of acidic or basic species. Examples of suitable sulfonic acid comonomers (and / or their alkali metal salt derivatives) include vinylsulfonic acid, allylsulfonic acid, ethenesulfonic acid, 2-acrylamido-1-methylpropanesulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid, 2-methylacrylamido-2-methylpropanesulfonic acid, and 2-sulfoethyl acrylate, with the sodium salt of 2-acrylamido-2-methylpropanesulfonic acid (AMPS) being the preferred comonomer.

[0150] Water-soluble polymers, whether polyvinyl alcohol polymers or other polymers, can be blended. When the polymer blend includes a blend of polyvinyl alcohol polymers, the PVOH polymer blend can include a first PVOH polymer ("first PVOH polymer"), which can include a PVOH homopolymer or a PVOH copolymer that includes one or more types of anionic monomer units (e.g., a PVOH ter- (or higher) copolymer polymer), and a second PVOH polymer ("second PVOH polymer"), which can include a PVOH homopolymer or a PVOH copolymer that includes one or more types of anionic monomer units (e.g., a PVOH ter- (or higher) copolymer polymer). In some aspects, the PVOH polymer blend includes only the first PVOH polymer and the second PVOH polymer (e.g., a binary blend of the two polymers). Alternatively or additionally, the PVOH polymer blend or a water-soluble film made therefrom can be characterized by being free or substantially free of other polymers (e.g., typically other water-soluble polymers, especially other PVOH-based polymers, or both). As used herein, "substantially free of" means that the first and second PVOH polymers account for at least 95 wt.%, at least 97 wt.%, or at least 99 wt.% of the total amount of water-soluble polymers in the water-soluble fiber or film.

[0151] In other aspects, the water-soluble film 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, and 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 film can include at least a third (or fourth, fifth, etc.) water-soluble polymer that is not a PVOH polymer (e.g., not a PVOH homopolymer or PVOH copolymer, with or without anionic monomer units).

[0152] The degree of hydrolysis (DH) of the PVOH homopolymer and the modified PVOH copolymer included in the water-soluble film of the present disclosure can be in the range of about 60% to about 99% or about 74% to about 99% (for example, for cold-water-soluble compositions, such as, about 74% to about 91%, about 79% to about 92%, about 80% to about 90%, about 88% to 92%, about 86.5% to about 89%, or about 88%, 90% or 92%; for example, for hot-water-soluble compositions, 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 greater than 99%). As the degree of hydrolysis decreases, the mechanical strength of the water-soluble film made of the polymer will decrease, but the solubility will be faster at temperatures below about 20°C. As the degree of hydrolysis increases, the water-soluble film made of the polymer will tend to have stronger mechanical strength at temperatures below about 20°C, but the solubility will be slower. The degree of hydrolysis of PVOH can be selected such that the water solubility of the polymer depends on temperature, and thus the solubility of the film made of the polymer and other ingredients will also be affected. In one option, the film is cold-water-soluble. For a copolymer (vinyl acetate vinyl alcohol) polymer that does not include any other monomers (e.g., a homopolymer that is not copolymerized with anionic monomers), a cold-water-soluble film that is soluble in water at temperatures below 10°C can include PVOH with a degree of hydrolysis in the range of about 74% to about 91%, or in the range of about 80% to about 90%, or in the range of about 85% to about 90%. In another option, the film is hot-water-soluble. For a copolymer (vinyl acetate vinyl alcohol) polymer that does not include any other monomers (e.g., a homopolymer that is not copolymerized with anionic monomers), a hot-water-soluble film that is soluble in water at temperatures of at least about 60°C can include PVOH with a degree of hydrolysis of at least about 98%.

[0153] When a PVOH polymer is referred to as having a specific degree of hydrolysis, the PVOH polymer will be understood to be a single polyvinyl alcohol polymer having the specified degree of hydrolysis, and a blend of polyvinyl alcohol polymers having a specified average degree of hydrolysis will generally be referred to as having an average (e.g., weight average) degree of hydrolysis.

[0154] The viscosity (μ) of the PVOH polymer is determined by measuring a freshly prepared solution using a Brookfield LV viscometer with a UL adapter, as described in the Brookfield test method in Appendix E of BS EN ISO 15023-2:2006. International practice specifies the viscosity of a 4% aqueous solution of polyvinyl alcohol at 20 °C. Unless otherwise stated, all viscosities specified herein in centipoise (cP) should be understood to refer to the viscosity of a 4% aqueous solution of polyvinyl alcohol at 20 °C. Similarly, when a polymer is described as having (or not having) a specific viscosity, unless otherwise specified, it means that the specified viscosity is the average viscosity of the polymer, which inherently has a corresponding molecular weight distribution. Additionally, when a resin comprises a blend of one or more PVOH polymers and the resin / blend is described as having (or not having) a specific viscosity, unless otherwise specified, it means that the specified viscosity is the weighted average viscosity of the resin / blend, which inherently has a corresponding weighted average molecular weight distribution.

[0155] In embodiments where the water-soluble film comprises PVOH, the average viscosity of the PVOH can be at least about 4 cP, about 5 cP, about 6 cP, about 8 cP, about 10 cP, about 12 cP, about 13 cP, about 13.5 cP, about 14 cP, about 15 cP, about 16 cP, about 17 cP, about 18 cP, about 19 cP, or about 20 cP and at most about 30 cP, about 28 cP, about 27 cP, about 26 cP, about 24 cP, about 22 cP, about 20 cP, about 19 cP, about 18 cP or about 17.5 cP, for example, in the range of about 10 cP to about 30 cP, or about 13 cP to about 27 cP, or about 13.5 cP to about 20 cP, or about 18 cP to about 22 cP, or about 14 cP to about 19 cP, or about 16 cP to about 18 cP or about 17 cP to about 16 cP, for example, 23 cP, or 20 cP or 16.5 cP. It is well known in the art that the viscosity of the PVOH polymer is related to the weight-average molecular weight of the PVOH polymer, and generally the viscosity is used as a surrogate for the weight-average molecular weight.

[0156] Other water-soluble polymers that can be used in the water-soluble film can include, but are not limited to, polyvinyl acetate, ethylene-vinyl alcohol, polyacrylate, poly(meth)acrylate, water-dispersible acrylate copolymer, polyvinylpyrrolidone, polyethyleneimine, polyalkylene oxide, polyacrylamide, polyacrylic acid and its salts, polymethacrylic acid, polycarboxylic acid and its salts, polyamino acid, polyamide, gelatin, quaternary ammonium salt polymer, polymethacrylate, and combinations of any of the foregoing. Water-soluble polymers, whether PVOH or others, are commercially available from various sources.

[0157] Water-soluble starch

[0158] The water-soluble starch of the present disclosure may include modified starch and / or unmodified starch. There are sources of starch having different molecular weights and amylose / amylopectin contents. These starches can be further processed to reduce the molecular weight (e.g., by acid hydrolysis) and by chemical modification. These factors affect the ease of gelatinization (the process by which starch granules dissolve in water during mixing) and the maximum solubility of the starch in water after gelatinization (cooking %). For example, a low molecular weight starch is required, which dissolves in water at a high molecular weight while PVOH is present at a high weight %.

[0159] Examples of unmodified starches include, for example, native starches such as corn starch, potato starch, sweet potato starch, wheat starch, cassava starch, sago starch, tapioca starch, rice starch, bean starch, kudzu starch, bracken starch, lotus seed starch, water chestnut starch, etc. Unmodified starches are naturally derived polysaccharides composed of dehydrated glucose units having 1_4α and 1-6α glycosidic bonds, thus forming linear or branched chains. The linear chains are called amylose, and the branched chains are called amylopectin. The branches in amylopectin typically occur in about 1 / 25 repeating units. Unmodified starches may also include starches to which no chemical moieties have been added to the polysaccharide. For example, unmodified starches may include starches whose molecular weight has been reduced by techniques such as acid hydrolysis.

[0160] By weight of the water-soluble starch, the amylose content in the water-soluble starch may be about 0-50 wt.%, about 0-30 wt.%, or about 0-25 wt.%, or about 1% to about 30% or about 5% to about 30%.

[0161] The water-soluble starch may be included in a water-soluble film and also in an aqueous solution used to form a water-soluble film, which is substantially gelatinized starch. In the water-soluble film and the aqueous solution, the water-soluble starch may be substantially or completely amorphous starch without starch crystalline or semi-crystalline regions.

[0162] The water-soluble starch may have a low molecular weight, for example, an average molecular weight in about 10 3 -10 6 g / mol, 10 3 -5x10 5 g / mol, 10 3 -10 5 g / mol, about 10 3 -5x10 4 g / mol or about 10 3 -10 4within the range of g / mol. The Brookfield viscosity of a 5 wt.% aqueous solution of water-soluble starch at about 20 rpm and about 87.8 °C can be in the range of about 1 - 2000 cP, about 1 - 1000 cP, about 1 - 500 cP, about 1 - 400 cP, about 1 - 300 cP, about 1 - 200 cP or 1 - 200 cP. It is well known in the art that the viscosity of water-soluble starch is related to the weight-average molecular weight of water-soluble starch, and generally viscosity is used as a surrogate for the weight-average molecular weight of water-soluble starch. Table 1 below shows an example of the Brookfield viscosity of two exemplary water-soluble cationic group-modified starches (Starch A and Starch B) at different starch weight percentages at 150 °F and 190 °F (87.8 °C). Starch A is a cationic group-modified starch having about 25 wt.% amylose and a degree of modification of about 0.18 mol.%.

[0163] Table 1. Brookfield viscosities of Starch A and Starch B at a shear rate of 20 rpm at 150 °F (65.5 °C) and 190 °F (87.8 °C).

[0164]

[0165] The modified starch can include ion group-modified starch, including cationic group-modified starch or anionic group-modified starch. Cationic group-modified starch can include cationic ammonium group-modified starch, including quaternary ammonium or amine group-modified starch, for example, trimethylammonium group-modified starch (reaction product of starch and trimethylammonium salt), reaction product of starch and 2-diethylaminoethyl chloride, reaction product of starch and 2,3-epoxypropyltrimethylammonium chloride, reaction product of starch and trimethylammonium.

[0166] The water-soluble film can include unmodified starch with a relatively low molecular weight. The water-soluble film can include neutral-modified starch (non-ion group-modified starch), such as hydroxyethyl starch or hydroxypropyl starch. The water-soluble film can include one or more of the following: unmodified starch, neutral-modified starch, anionic group-modified starch, cationic group-modified starch, or a combination thereof. The low average molecular weight of unmodified starch or neutral-modified starch can be about 10 3 -10 6 g / mol, about 10 3 -10 5 g / mol, about 10 4 -10 5 g / mol or about 10 3 -10 4within the range of g / mol. The amount of amylose in unmodified starch or neutrally modified starch can be about 0 - 50 wt.%, about 0 - 40 wt.%, about 0 - 30 wt.%, about 0 - 25 wt.%, or about 1% to about 40% or about 5% to about 40%.

[0167] An aqueous starch solution is intended to mean a starch solution in which the solvent contains water as the main component, or a starch solution in which water accounts for at least 90%, or at least 95%, or all of the starch solvent. As is well known, starch is a carbohydrate composed of a large number of glucose units linked by glycosidic bonds. The starch of the present disclosure can be obtained from seeds, rhizomes or tubers through wet milling, washing, sieving and drying. Starch is mainly obtained from corn, wheat and potatoes, and secondly from sources such as rice, sweet potatoes, sago and mung beans. Starch can be unmodified or chemically modified so that the starch functions under the conditions encountered during the processing of the present disclosure, such as interacting with the PVOH polymer through ionic and / or hydrogen bonding interactions. Such modifications include, but are not limited to, acid treatment, alkali treatment, bleaching, oxidation, enzyme treatment, acetylation, phosphorylation or combinations thereof. Modified starch can include cationic starch, hydroxyethyl starch, hydroxypropyl starch and carboxymethyl starch. The starch can contain modified starch. The starch can be or can contain starch modified with cationic groups.

[0168] The present inventors have tested various starches and polysaccharides and found that many combinations of starch and PVOH are immiscible, presenting a phase separation problem in the film-forming solution. However, the miscibility of cationic group-modified starch, i.e., starch A, with anion group-modified PVOH resins (e.g., PVOH modified with monomethyl malate and PVOH modified with methyl acrylate) is very high. Starch A is a low-molecular-weight cationic quaternary ammonium group-modified starch with approximately 25 wt.% amylose and a modification degree of approximately 0.18 mol.%. The following polyvinyl alcohol (PVOH) resins are used in each example. Resin A is an anion group-modified polyvinyl alcohol (PVOH), which is polyvinyl alcohol modified with monomethyl maleate (MMM), with a modification degree of approximately 1.5 - 2.0 mol.% and a hydrolysis degree of 89 - 91 mol.%. Resin B is an anion group-modified polyvinyl alcohol (PVOH), which is polyvinyl alcohol modified with methyl acrylate (MA), with a modification degree of approximately 1 - 10 mol.% and a hydrolysis degree of 80 - 99 mol.%. Without being bound by any particular theory, it is believed that the observed high miscibility is the result of the ionic attraction between anion group-modified PVOH and cation group-modified starch; the high miscibility enables the film-forming aqueous solution to have a high solid content, which, based on the weight of the film-forming solution at a high starch loading level, can be higher than 32 wt.% total solids, based on the total solid content in the aqueous solution, the high starch loading level being in the range of approximately 5 - 65 wt.% or approximately 25 - 60 wt.%, and also achieving an RCI higher than 50%. Previous starch and PVOH mixtures were all aqueous dispersions or suspensions, or mixtures of modified starch and homopolymer PVOH at very low loading levels, or starch and PVOH were phase-separated in the mixture. In addition, high-molecular-weight starches that are completely insoluble or only slightly soluble are generally used in polyvinyl alcohol films to reduce film adhesion and modify the coefficient of friction of such films; similarly, for the above purposes, a higher particle size of such starches is also preferred.

[0169] The starch can include neutral charge-modified starch, such as starch C, which is hydroxyethyl-modified starch, having a low molecular weight, approximately 25 wt.% amylose, and a modification degree lower than approximately 3 mol.%. The miscibility of starch C with anionic PVOH is very high. In formulations with an RCI higher than 50%, water-soluble films were successfully prepared using starch C as the main starch. However, although the miscibility between PVOH and starch C is good, at very high starch loading levels, its miscibility is not as good as that of cationic group-modified starch (such as starch A). At a total solid content of approximately 10 wt.% or higher, when the weight ratio of starch C to PVOH is higher than approximately 45:55, PVOH and neutral group-modified starch (starch C) phase-separate in the film-forming solution.

[0170] The modified starch may include starch modified with anionic groups or starch modified with cationic groups. The modified starch includes starch modified with cationic groups. The starch modified with cationic groups may include starch modified with amino or ammonium groups (such as quaternary amine or ammonium groups, primary amino groups, secondary amino groups or tertiary amino groups). The starch modified with cationic groups may include starch modified with quaternary ammonium groups. The degree of modification of the starch modified with cationic groups, such as the starch modified with cationic groups described herein, may be in the range of about 0.05-10 mol.%, about 0.1-8 mol.%, 0.1-5 mol.%, 0.1_4 mol.%, 0.1-3.5 mol.%, 0.1-2 mol.%, 0.1-1 mol.%, 0.2-5 mol.%, 0.2-0.5 mol.%, about 0.1-0.3%, about 0.18 mol.% or about 0.21 mol.%.

[0171] Non-limiting examples of the starch modified with cationic groups may have the structure of formula A as discussed above.

[0172] Non-limiting examples of the starch modified with cationic groups may have structures according to formula B to formula I as shown below, where R1, R2, R3, R5 and R6 are each independently hydrogen (H), C1-C6 alkyl or C1-C6 hydroxyalkyl, where R4 and R7 are independently straight-chain or branched C1-C 10 alkylene or C1-C 10 hydroxyalkylene, or straight-chain or branched C1-C6 alkylene or C1-C6 hydroxyalkylene, optionally substituted with one or more heteroatom-containing groups, and where A is C1-C6 alkylene or C1-C6 hydroxyalkylene, or a hydrocarbon group containing oxygen, nitrogen or sulfur.

[0173]

[0174]

[0175]

[0176] A may be a hydrocarbon group containing one or more heteroatoms selected from the group consisting of oxygen, nitrogen and sulfur. The hydrocarbon group containing oxygen, nitrogen or sulfur may have one of the following formulas:

[0177] -(CR8R9) n 、-O-, where n is 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10; (i)

[0178] -[(CR8R9) n O] m -, where n and m are independently 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10; (ii)

[0179] -(CR8R9) n -S-, where n is 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10; (iii)

[0180] -[(CR8R9) n S] m -,where n and m are independently 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10; (iv)

[0181] -(CR8R9) n -NR 10 -,where n is 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10; (v)

[0182] -[(CR8R9) n NR 10 m -,where n and m are independently 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10; (vi)

[0183] where R8, R9 and R 10 are each independently hydrogen, C1-C6 alkyl, C1-C6 cycloalkyl or aryl.

[0184] As used herein, the terms "cationic group-modified starch" and "cationic starch" are used in the broadest sense herein. In one aspect of the present invention, cationic starch refers to starch that has been chemically modified such that the starch carries a net positive charge in an aqueous solution under acidic conditions (pH below 7, e.g., pH 3). Such chemical modification can include, but is not limited to, adding amino and / or ammonium groups to the starch molecule. Non-limiting examples of such ammonium groups can include the groups or substituents discussed above, such as trimethylhydroxypropylammonium salts (such as halide salts or chloride salts), dimethylstearoylhydroxypropylammonium salts (such as halide salts or chloride salts), dimethyldodecylhydroxypropylammonium salts (such as halide salts or chloride salts), 2-diethylaminoethyl salts (such as halide salts or chloride salts) or 2,3-epoxypropyltrimethylammonium salts (such as halide salts or chloride salts). Non-limiting examples of such ammonium groups can include the groups or substituents discussed above, such as trimethylhydroxypropylammonium chloride, dimethylstearoylhydroxypropylammonium chloride, dimethyldodecylhydroxypropylammonium chloride, 2-diethylaminoethyl chloride or 2,3-epoxypropyltrimethylammonium chloride.

[0185] Non-limiting examples of quaternary ammonium group-modified starch can include the reaction products of starch with one or more of the following: trimethylhydroxypropylammonium salts, dimethylstearoylhydroxypropylammonium salts, dimethyldodecylhydroxypropylammonium salts, 2-diethylaminoethyl salts or 2,3-epoxypropyltrimethylammonium salts.​

[0186] Based on the weight of the water-soluble film, the water-soluble starch can be present in the water-soluble film in an amount within the following ranges: about 5-75 wt.%, about 5-70 wt.%, about 10-65 wt.%, about 10-60 wt.%, about 10-55 wt.%, about 10-50 wt.%, about 15-50 wt.%, about 20-50 wt.%, about 20-45 wt.%, about 25-45 wt.%, about 30-55 wt.%, about 35-55 wt.% or about 30-50 wt.%. The weight ratio of the water-soluble starch to polyvinyl alcohol (PVOH) can be from about 5:95 to about 95:5, from about 10:90 to about 90:10, from about 15:85 to about 85:15, from about 20:80 to about 80:20, from about 30:70 to about 70:30, from about 35:65 to about 65:35, from about 40:60 to about 60:40, from about 45:55 to about 55:45 or from about 30:70 to about 80:20; or about 50:50.

[0187] Based on the total weight of the starch, the amylose of the starch can be in the range of about 0-50 wt.%, about 0-40 wt.%, about 0-30 wt.% or about 0-25 wt.%.

[0188] The film can be free or substantially free of octenyl succinic anhydride-modified starch.

[0189] Plasticizer

[0190] The water-soluble film can further comprise one or more plasticizers.

[0191] A plasticizer is a liquid, solid or semi-solid that is added to a material (usually a resin or an elastomer) to make the material softer, more flexible (by lowering the glass transition temperature and crystallinity of the polymer) and easier to process. Alternatively, the polymer can be internally plasticized by chemically modifying the polymer or the monomer. Additionally or alternatively, the polymer can be externally plasticized by adding a suitable plasticizer. Water is considered a very efficient plasticizer for PVOH and other polymers; the polymers include but are not limited to water-soluble polymers. However, the volatility of water limits its practicality because the polymer film needs to have at least a certain degree of resistance (toughness) to various environmental conditions (including low relative humidity and high relative humidity).

[0192] Suitable non-aqueous plasticizers include, but are not limited to, glycerol (also known as glycerol or glycerin), diglycerol (also known as diglyceryl), sorbitol, ethylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, tetraethylene glycol, propylene glycol, polyethylene glycol up to 400 MW, neopentyl glycol, trimethylolpropane (TMP), polyether polyols, 2-methyl-1,3-propanediol (e.g., MP ), ethanolamine, isomaltitol, maltitol, xylitol, erythritol, adonitol, galactitol, pentaerythritol, mannitol, and combinations of the foregoing.

[0193] The non-aqueous plasticizer can comprise a bio-based plasticizer or a plant-derived plasticizer. The plasticizer can comprise a bio-based water-soluble plasticizer. The plasticizer comprises one or more bio-based water-soluble plasticizers selected from the group consisting of sorbitol, glycerol, ethylene glycol, xylitol, ethanolamine, mannitol, polyethylene glycol up to 400 MW, and propylene glycol. The plasticizer can comprise a mixture of sorbitol and glycerol.

[0194] When present, the total amount of plasticizer present in the water-soluble film can be in the range of up to about 50 wt.%, based on the weight of the water-soluble film, e.g., about 0.01% to about 50 wt.%, about 0.1 wt.% to about 45 wt.%, about 1 wt.% to about 40 wt.%, about 2 wt.% to about 30 wt.%, about 3 wt.% to about 20 wt.%, or about 3 wt.% to about 15 wt.%, e.g., about 5 wt.%. The total amount of plasticizer can also be expressed as parts per hundred parts of polymer of both polyvinyl alcohol (PVOH) and water-soluble starch. Thus, the total amount of plasticizer can be in the range of: about 2 phr to about 70 phr, about 5 phr to about 65 phr, about 10 phr to about 60 phr, about 15 phr to about 50 phr, about 20 phr to about 55 phr, about 25 phr to about 50 phr, about 30 phr to about 45 phr, or about 30 phr to about 40 phr.

[0195] Based on the weight of the water-soluble film, glycerol can be used in the following amounts: about 1 wt.% to about 40 wt.%, about 5 wt.% to about 30 wt.%, 10 wt.% to about 25 wt.%, 15 wt.% to about 25 wt.%, or 16 wt.% to about 20 wt.%, for example, about 18 wt.%. Based on the weight of the water-soluble film, sorbitol can be used in the following amounts: about 1 wt.% to about 30 wt.%, about 1 wt.% to about 20 wt.%, about 2 wt.% to about 15 wt.%, about 3 wt.% to about 13 wt.%, or about 4 wt.% to about 10 wt.%, for example, about 5 wt.%. The plasticizer can comprise a mixture of sorbitol and glycerol in a weight ratio within the following ranges: about 1:10 to about 3:1, about 1:8 to about 2:1, about 1:6 to about 1:1, about 1:5 to about 1:2, or about 1:4 to about 1:2. The plasticizer levels consistent with those in the examples described herein can serve both as representative levels for water-soluble film formulations having various other components herein and as upper and lower bounds for various ranges. In certain embodiments, the specific type and amount of the plasticizer can be selected based on the desired film flexibility and the processing characteristics of the water-soluble film. In the case of low plasticizer levels, the film may become brittle, difficult to process, or prone to breakage. In the case of elevated plasticizer levels, the film may be too soft, too weak, or difficult to process for the desired use.

[0196] Surfactant

[0197] Surfactants for water-soluble films are well known in the art. Surfactants can be included to aid in the dispersion of the resin solution during casting. Suitable surfactants for the water-soluble films of the present disclosure include, but are not limited to, linear aliphatic ethoxylated surfactants, laureth-6 formate, C9-C 15 ethylene oxide, C10-Guerbet alcohol, C10-Guerbet alcohol ethoxylate POE(8), laureth-3, laureth-5, laureth-7, oleth-10 formate, dialkyl sulfosuccinates, lactylated fatty acid esters of glycerol and propylene glycol, lactate esters of fatty acids, sodium alkyl sulfate, polysorbate 20, polysorbate 60, polysorbate 65, polysorbate 80, alkyl polyethylene glycol ethers, lecithin, acetylated fatty acid esters of glycerol and propylene glycol, sodium lauryl sulfate, acetylated esters of fatty acids, myristyl dimethylamine oxide, trimethyl tallow alkyl ammonium chloride, quaternary ammonium compounds, alkali metal salts of higher fatty acids containing from about 8 to 24 carbon atoms, alkyl sulfates, alkyl polyethoxylated sulfates, alkyl benzene sulfonates, monoethanolamine, laureth, propylene glycol, diethylene glycol, their salts, and combinations of any of the foregoing. The linear aliphatic ethoxylated surfactant can comprise laureth-6 formate, C9-C 15 ethylene oxide, or combinations thereof.

[0198] Suitable surfactants can 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 from about 8 to 24 carbon atoms, alkyl sulfates, alkyl polyethoxylated sulfates, and alkylbenzene sulfonates (anionic), and amine oxides, N-alkyl betaines, and sulfobetaines (zwitterionic). Other suitable surfactants include sodium dioctyl sulfosuccinate, lactylated fatty acid esters of glycerin and propylene glycol, lactate esters of fatty acids, sodium alkyl sulfate, 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.

[0199] Based on the weight of the water-soluble film, the amount of surfactant in the water-soluble film can be in the following ranges: about 0.05 wt.% to about 10.0 wt.%, about 0.05 wt.% to about 5.0 wt.%, about 0.1 wt.% to about 2.5 wt.%, about 0.1 wt.% to about 2.0 wt.%, about 0.1 wt.% to about 1.5 wt.%, about 0.1 wt.% to about 1.0 wt.%, about 0.1 wt.% to about 0.8 wt.%, about 0.2 wt.% to about 0.8 wt.%, or about 0.2 wt.% to about 0.4 wt.%. The amount of surfactant in the water-soluble film can be expressed as parts per hundred parts of total polymer (phr) of polyvinyl alcohol (PVOH) and water-soluble starch in the water-soluble film, and can be present in the following ranges: about 0.1 phr to about 5 phr, about 0.1 phr to about 4 phr, about 0.2 phr to about 3.0 phr, about 0.3 phr to about 2.0 phr, about 0.4 phr to about 1.5 phr, about 0.4 phr to about 1.0 phr, about 0.4 phr to about 0.8 phr, about 0.5 to about 0.7 phr, or about 0.3 phr to about 1.0 phr.

[0200] It has been found that blends of surfactants are advantageous for water-soluble films, the blends comprising anionic monomers selected from the group consisting of maleic acid, maleic anhydride, monoalkyl maleates, dialkyl maleates, and combinations thereof. Thus, in one aspect of the present disclosure, the PVOH can comprise anionic monomers selected from the group consisting of maleic acid, maleic anhydride, monoalkyl maleates, monomethyl maleate (MMM), dialkyl maleates, methyl acrylate (MA), and combinations thereof, wherein the total level of anionic side groups from the PVOH can be at least about 1 mol.%, about 2 mol.%, about 3 mol.%, at least about 3.5 mol.%, at least about 4.0 mol.%, at least about 6 mol.%, or at least about 8 mol.%, or in the range of about 1-10 mol.%, about 2-8 mol.%, or about 3-5 mol.%, and the water-soluble film can further comprise a nonionic surfactant, an amine oxide surfactant, an anionic surfactant, a cationic surfactant, or combinations thereof.

[0201] The nonionic surfactant can be selected from the group consisting of polyoxyethylated polyoxypropylene glycols, alcohol ethoxylates, alkylphenol ethoxylates, tertiary alkynediols, alkanolamides, C10-Guerbet alcohols, and combinations thereof. The amine oxide surfactant can be selected from the group consisting of dimethyloctylamine oxide, dimethyldecylamine oxide, dimethyldodecylamine oxide, dimethyltetradecylamine oxide, dimethylhexadecylamine oxide, dimethyloctadecylamine oxide, and combinations thereof. It will be understood that commercially available amine oxide surfactants can be blends of the foregoing, as the source of the amine can include a distribution of amines of various chain lengths. Thus, for example, "dimethyldodecylamine oxide" can include a distribution of amine oxides, wherein the average amine oxide and / or the major portion of the amine oxide can comprise a dodecyl chain. The anionic surfactant can comprise sodium dioctyl sulfosuccinate. The cationic surfactant can be selected from the group consisting of polyoxyethylene amines, quaternary ammonium salts, quaternized polyoxyethylene amines, and combinations thereof.

[0202] Each surfactant present in the water-soluble film can be present in an amount in the range of about 1 wt.% to about 98 wt.%, or about 10 wt.% to about 80 wt.%, or about 15 wt.% to about 70 wt.%, or about 16 wt.% to about 68 wt.%, or about 17 wt.% to about 42 wt.%, or about 30 wt.% to about 40 wt.% of the total amount of surfactant.

[0203] Other additives

[0204] Suitable lubricants / demolding agents may include, but are not limited to, fatty acids and their salts, fatty alcohols, fatty esters, fatty amines, fatty amine acetates, and fatty acid amides. Preferred lubricants / demolding agents are fatty acids, fatty acid salts, and fatty amine acetates. For example, based on the weight of the water-soluble film, the amount of the lubricant / demolding agent in the water-soluble film may be in the range of about 0.02 wt.% to about 1.5 wt.%, optionally about 0.1 wt.% to about 1 wt.%.

[0205] Fillers may be included in the water-soluble film and may include bulking agents, extenders, anti-blocking agents, anti-sticking agents, and combinations thereof. Suitable fillers / bulking agents / extenders / anti-blocking agents / anti-sticking agents include, but are not limited to, water-insoluble starches, water-insoluble modified starches, cross-linked polyvinylpyrrolidone, cross-linked cellulose, microcrystalline cellulose, silica, metal oxides, calcium carbonate, talc, mica, stearic acid, and its metal salts, such as magnesium stearate. Preferred materials are water-insoluble starches, water-insoluble modified starches, silica, and talc powder. The starches and modified starches used as fillers are granular starches and not the water-soluble starches defined in the present disclosure. In one type of embodiment, based on the weight of the water-soluble film, the amount of the filler / extender / anti-blocking agent / anti-sticking agent in the water-soluble film may be in the range of about 0.5 wt.% to about 6 wt.%, about 0.6 wt.% to about 5 wt.%, about 0.7 wt.% to about 4 wt.%, about 0.8 wt.% to about 3 wt.%, about 0.9 wt.% to about 2 wt.%, about 1 wt.% to about 1.8 wt.%, or about 1 wt.% to about 1.5 wt.%, or for example, in the range of about 1 phr to about 6 phr, or about 1 phr to about 5 phr, or about 1 phr to about 4 phr, or about 2 phr to about 4 phr per 100 parts of the total of PVOH and water-soluble starch.

[0206] In some embodiments, the water-soluble film may include 1 or more phr (e.g., 2 phr to 6 phr or 2 phr to 4 phr) of filler. In some embodiments, the film includes 2 or more phr (e.g., 2 phr to 6 phr or 2 phr to 4 phr) of filler, and the filler may include a bulking agent, an anti-blocking agent, or a combination thereof. Without being bound by theory, it is believed that when a plasticizer is included in an amount greater than or equal to 30 phr (e.g., in the range of 30 phr to 50 phr), including 2 or more phr (e.g., 2 phr to 6 phr or 2 phr to 4 phr) of filler may be useful to prevent the plasticizer from exuding or migrating from the film.

[0207] An anti-blocking agent (e.g., SiO2 and / or stearic acid) may be present in the film in the following amounts per 100 parts of the total amount of PVOH and water-soluble starch: at least 0.1 PHR, at least 0.5 PHR or at least 1 PHR or in the range of about 0.1 to 5.0 PHR, about 0.5 to about 5.0 PHR, about 1.0 to 4.0 PHR, about 1.5 to about 4.0 PHR, about 2.0 to about 4.0 PHR, about 2.5 to about 4.0 PHR, about 3.0 to about 4.0 PHR or about 3.0 to 3.5 PHR.

[0208] Suitable median particle sizes of the anti-blocking agent include median sizes in the following ranges: about 3 microns to about 11 microns, or about 4 microns to about 11 microns, or about 4 microns to about 8 microns, or about 5 microns to about 6 microns, such as 5 microns, 6 microns, 7 microns, 8 microns or 9 microns. Suitable SiO2 is untreated synthetic amorphous silica designed for use in aqueous systems.

[0209] The water-soluble film may further have a residual moisture content of at least 4 wt.%, e.g., in the range of about 4 wt.% to about 10 wt.%, as measured by Karl Fischer titration.

[0210] The renewable carbon index (RCI) of the water-soluble film of the present disclosure may be higher than about 30%, about 40%, about 50%, about 55%, about 60%, about 70%, about 80% or about 90%, or in the range of about 30 - 90%, about 40 - 80%, about 40 - 70%, about 45 - 70%, about 45 - 65% or about 50 - 60%.

[0211] Method for preparing an aqueous solution for forming a water-soluble film

[0212] The present disclosure provides a method for preparing an aqueous solution suitable for forming a water-soluble film as discussed above. The method for preparing the aqueous solution may comprise the steps of: 1) heating water in a container to a temperature in the range of about 60 - 95 °C, such as about 85 °C; 2) adding water-soluble starch to the water; 3) continuing to heat and mix for about 0.5 - 20 hours, such as about 0.5 - 3 hours or about 1 hour, at a temperature in the range of about 60 - 95 °C, such as at about 85 °C, to form a gelatinized starch liquid solution; 4) adding water-soluble polyvinyl alcohol (PVOH) to the starch liquid solution; and 5) heating and mixing for about 0.5 - 20 hours at a temperature in the range of about 60 - 95 °C, such as at about 85 °C, to form an aqueous solution of starch and PVOH, wherein the gelatinization % of the water-soluble starch under batch cooking conditions (heating and mixing in water at about 95 °C for about 30 minutes) is at least about 5 wt.%, at least about 10 wt.%, or at least about 15 wt.%, wherein the total solids content of the aqueous solution is at least 15 wt.% by weight of the aqueous solution, wherein the water-soluble starch is present in an amount of about 5 - 65 wt.% by weight of the total solids content, and wherein at about room temperature, by visual observation, the water-soluble polyvinyl alcohol (PVOH) and the water-soluble starch are miscible in the aqueous solution and there is no phase separation for at least 24 hours.

[0213] When preparing an aqueous solution of PVOH and water-soluble starch, it is desirable to have sufficient time, heat, and shear force to gelatinize the starch and completely dissolve it in hot water, and further uniformly mix it with PVOH to form a miscible solution, and thus prevent phase separation between PVOH and water-soluble starch.

[0214] Generally, an aqueous solution can be prepared by: first adding polyvinyl alcohol (PVOH) to hot water, and then adding water-soluble starch; or alternatively, first adding water-soluble starch to hot water, and then adding polyvinyl alcohol. The order of adding polyvinyl alcohol and water-soluble starch to hot water is not particularly limited.

[0215] In some cases, when adding starch to the hopper of a hot water container, due to the steam from the hot water, there may be a problem of starch caking. To avoid starch caking, the starch can first be added to cold water under about ambient conditions to form a cold slurry, and then mixed and heat-treated to gelatinize and completely dissolve the water-soluble starch. Accordingly, the method may comprise first adding the water-soluble starch to water under ambient conditions or cold water in the range of about 5 °C to about 30 °C to form a cold slurry, and then mixing and heat-treating the water-soluble starch to a temperature in the range of about 60 - 95 °C, such as about 85 °C, to gelatinize and completely dissolve the starch, and then adding PVOH.

[0216] Alternatively, the starch sizing agent can be gelatinized by steam injection or jet cooking, i.e., the sizing agent can be heated by a jet cooker and high shear can be applied to the starch. Jet cooking can increase the degree of gelatinization of the starch, which can improve the solubility of the starch and reduce retrogradation. In the jet cooker, steam is continuously injected into the flowing starch sizing agent through an injector coaxial with the starch stream.

[0217] After heat treatment and mixing in hot water at a temperature in the range of about 60 - 95°C, for example, at a temperature of about 85°C, for about 0.5 - 20 hours or about 0.5 - 5 hours, the water-soluble starch gelatinizes and completely dissolves in water.

[0218] Both PVOH and the water-soluble starch can completely dissolve in the aqueous solution, and can be miscible in the aqueous solution without phase separation or bulk phase separation. In the aqueous solution of the present disclosure, the miscibility between PVOH and the water-soluble starch is beneficial to improving the forming or casting processability of the water-soluble film. Further, the obtained aqueous solution can remain stable for a long time, so that the holding time of the aqueous solution can be extended before forming the film. Generally, if PVOH and starch are immiscible in the liquid mixture, once phase separation (e.g., liquid phase separation) occurs between PVOH and the water-soluble starch, it is impractical to remix them into a miscible solution.

[0219] PVOH can include PVOH modified with anionic groups modified by monomethyl maleate (MMM), with a modification degree of about 1 - 5 mol.%, and wherein the water-soluble starch is added to water before PVOH. When preparing the aqueous solution using MMM-modified starch, the starch can be added to and dissolved in hot water at a temperature in the range of about 60 - 95°C before adding PVOH.

[0220] The method can further include: adding a plasticizer and an antifoaming agent to water while mixing before adding the water-soluble starch; adding an anti-sticking agent while adding the water-soluble starch to water; adding an additive (antioxidant) to the gelatinized starch liquid solution after adding the water-soluble starch and before adding PVOH; and adding a surfactant to the aqueous solution and mixing for about 5 - 60 minutes. Alternatively, after dissolving PVOH, any one or more of the plasticizer, antifoaming agent, anti-sticking agent, and other additives can be added to the solution.

[0221] A method for preparing an aqueous solution may comprise the following steps: 1) heating water in a container to a temperature in the range of about 60 - 95 °C, such as about 85 °C; 2) adding water-soluble polyvinyl alcohol (PVOH) to the water; 3) continuing to heat and mix for about 0.5 - 20 hours, such as about 0.5 - 3 hours or about 1 hour, at a temperature of about 60 - 95 °C, such as about 85 °C, to form a liquid solution; 4) adding water-soluble starch to the liquid solution; and 5) heating and mixing for about 0.5 - 20 hours at a temperature in the range of about 60 - 95 °C to form an aqueous solution, wherein the gelatinization % of the water-soluble starch under batch cooking conditions is at least about 10 wt.% (heating, such as using direct steam injection and mixing in water at about 95 °C for about 30 minutes), wherein the total solids content of the aqueous solution is at least 15 wt.% by weight of the aqueous solution, wherein the water-soluble starch is present in an amount of about 5 - 65 wt.% by weight of the total solids content, and wherein by visual observation, after storage at about room temperature to about 90 °C for at least about 24 hours, about 36 hours, about 48 hours, about 60 hours, about 1 week or about 2 weeks, or even more than 2 weeks, the water-soluble polyvinyl alcohol (PVOH) and the water-soluble starch are miscible in the aqueous solution and there is no phase separation.

[0222] For example, the viscosity of the aqueous solution may be at least about 2,000 or 3,000 cps at 185 °F (85 °C), and may be at most about 20,000 cps, about 15,000 cps or about 10,000 cps at 185 °F, such as may be about 3,000 cps to about 10,000 cps at 185 °F (85 °C).

[0223] The PVOH may comprise PVOH modified with anionic groups modified by methyl acrylate (MA), with a modification degree of about 1 - 5 mol.%, and optionally wherein the PVOH is added to the water before the water-soluble starch.

[0224] The PVOH and the water-soluble starch are completely dissolved in the aqueous solution and are miscible, and further there is no phase separation in the aqueous solution.

[0225] The method may further comprise: adding a plasticizer and an antifoaming agent to the water while mixing before adding the PVOH; adding additives (an antioxidant and caustic soda) to the water before adding the PVOH; adding an anti-blocking agent together with the water-soluble starch to the liquid solution; and adding a surfactant to the aqueous solution and mixing for about 5 - 60 minutes.

[0226] Mix and cast an aqueous formulation. Mixing is carried out in a container while heating. The order of ingredient addition can be a plasticizer, an antifoaming agent, water-soluble starch, an additive, PVOH, and finally a surfactant. Sufficient time, heat, and shear force are desired to gelatinize the water-soluble starch and completely dissolve it in hot water and uniformly mix it with the PVOH resin. After mixing, the resulting aqueous solution can be stored in a 90 °C oven overnight for degassing, optionally under reduced pressure. For the control PVOH / starch solutions described below, if the formulation is phase-unstable or immiscible, the PVOH and starch will phase-separate during storage. The phase-separated solution will either not be castable or, once castable, will form a large number of PVOH-rich domains and a large number of starch-rich domains, which will result in poor mechanical properties in the starch-rich regions. Thus, the miscible and phase-stable aqueous solutions of PVOH and water-soluble starch of the present disclosure have advantages such as good film-forming processability and excellent physical properties of the resulting film.

[0227] In a non-limiting example, an aqueous solution of the present disclosure containing cationic group-modified starch (Starch A) and PVOH modified by monomethyl maleate (MMM) (Resin A) is prepared according to the following formation steps: Heat water to about 85 °C; add a plasticizer (e.g., glycerol and sorbitol) and an antifoaming agent while the water is heating; add water-soluble starch to gelatinize it and mix for about 1 hour (and any water-insoluble starch particles can be added together with the water-soluble starch as an anti-blocking agent); add other additives and mix for about 20 minutes (sodium metabisulfite); add Resin A and mix for about 1 hour; add a surfactant and mix for about 10 minutes to form an aqueous solution. After mixing, the resulting aqueous solution can be stored in a 90 °C oven overnight for degassing, optionally under reduced pressure.

[0228] Method for preparing a water-soluble film

[0229] The present disclosure provides a method for forming the water-soluble film discussed above. The method can include casting the aqueous solution discussed above onto a substrate at a specified thickness; and drying the water in the cast aqueous solution to form a water-soluble film. The viscosity of the cast solution can be, for example, at least about 2,000 or about 3,000 cps at 185 °F (85 °C), and can be, for example, at most about 20,000, about 15,000, or about 10,000 cps at 185 °F (85 °C), for example, can be, for example, about 3,000 cps to about 10,000 cps at 185 °F (85 °C).

[0230] One class of contemplated embodiments is characterized in that the water-soluble film is formed by solvent casting of an aqueous solution as discussed above. The solvent casting process for the film-forming aqueous solution is known in the art and will be described in detail below. For example, in the film-forming process, water-soluble polyvinyl alcohol, water-soluble starch, and secondary additives are dissolved in a solvent (usually water) to form an aqueous solution as discussed above, metered onto a surface, diffused on the surface, substantially dried (or forced dried) to form a cast film, and then the resulting cast film is removed from the casting surface. The process can be carried out batchwise and more efficiently in a continuous process.

[0231] In forming a continuous water-soluble film as discussed above, the conventional practice is to meter the aqueous solution onto a moving casting surface, such as a continuously moving metal cylinder or belt, so that the solvent is substantially removed from the liquid, thereby forming a self-supporting cast film, and then peeling the resulting cast film from the casting surface.

[0232] Optionally, the water-soluble film can be a self-supporting film composed of one layer or multiple similar layers.

[0233] In a non-limiting example, a water-soluble film is prepared by the following steps: casting the phase-stable aqueous solution of the present disclosure onto a heated steel substrate and drying the water in the cast aqueous solution to form a water-soluble film, wherein the temperature of the substrate can be heated, and the target thickness of the dried film can be any desired thickness, such as in the range of 5 μm to 200 μm, or 20 μm to 100 μm, or 40 μm to 90 μm, or 50 μm to 80 μm, such as 76 μm.

[0234] Sachet

[0235] The present disclosure provides an article that includes a sachet made of the water-soluble film discussed above, the sachet defining an internal sachet volume. The article can further include a chemical composition contained in the internal sachet volume. The chemical composition can be a household care composition. The household care composition can be a liquid laundry detergent. The advantage of the sachet of the present disclosure can be that the sachet compression strength is increased, being at least about 300 N, at least about 600 N, or at least about 800 N, or at least about 1000 N or at least about 1200 N.

[0236] The residue of an article comprising a sachet and a chemical composition after mixing in water at a temperature of about 15 °C for about 8.5 minutes can be no more than about 10 wt.%, no more than about 5 wt.%, or no more than about 2.5 wt.%. Based on the weight of the sachet, the residue of the article after mixing in water at a temperature of about 15 °C for about 8.5 minutes can be no more than about 10 wt.%, no more than about 5 wt.%, or no more than about 2.5 wt.%. The residue of the article after mixing in water at a temperature of about 10 °C for about 8.5 minutes can be no more than about 10 wt.%, no more than about 5 wt.%, or no more than about 2.5 wt.%. The residue of the article after mixing in water at a temperature of about 5 °C for about 8.5 minutes can be no more than about 10 wt.%, no more than about 5 wt.%, or no more than about 2.5 wt.%.

[0237] The sachets of the present disclosure can include at least one sealed compartment. Thus, the sachet can contain a single compartment or multiple compartments. The water-soluble sachet can be formed from two layers of water-soluble film sealed at the interface, or from a single film that is folded and sealed upon itself. The film defines an internal sachet container volume that contains any desired composition for release into an aqueous environment. The composition is not particularly limited and includes, for example, any one of the various compositions described below.

[0238] The sachet can be of a matte-to-matte seal type. The water-soluble film prepared by the film casting method can have two surfaces. One surface contacts the casting substrate and is generally matte. The other surface that does not contact the casting substrate is smoother, glossier, and may be more aesthetically appealing to the customer. Thus, the seal of the sachet can mate with the matte surface such that the two exposed film surfaces of the sachet are smooth and glossy. The sachet made of the water-soluble film (optionally of the matte-to-matte seal type) exhibits good sealing properties, and the compressive strength of the article can be higher than about 300 N, about 600 N, about 800 N, about 1000 N, or about 1200 N.

[0239] The water-soluble films disclosed herein can be used to produce sachets for containing chemical compositions therein. The chemical composition can be a home care composition, such as a detergent or a liquid laundry detergent. The sachet composition can take any form, such as a powder, gel, paste, liquid, tablet, or any combination thereof. The films according to the present disclosure can also be used in any other applications that require improved wet processing and low cold water residues. The film forms at least one sidewall of the sachet, optionally forms the entire sachet, and preferably forms the outer surface of the at least one sidewall.

[0240] The water-soluble films described herein can also be used to manufacture sachets having two or more compartments, the compartments being made of the same film or in combination with films of other polymeric materials. The additional films can be obtained, for example, by casting, blow molding, extrusion or coextrusion of the same or different polymeric materials, as known in the art.

[0241] In embodiments comprising a plurality of compartments, each compartment can contain the same and / or different compositions. Further, the compositions can take any suitable form, including but not limited to liquids, solids, and combinations thereof (such as solids suspended in liquids). The sachet can comprise a first compartment, a second compartment, and a third compartment, each containing a different first composition, second composition, and third composition, respectively.

[0242] Any suitable equipment and methods can be used to make sachets and packets. For example, single-compartment sachets can be manufactured using vertical form filling, horizontal form filling, or rotary drum filling techniques common in the art. Such processes can be continuous or intermittent. The film can be damped and / or heated to increase its ductility. The method can also use a vacuum to draw the film into a suitable mold. Once the film is on the horizontal portion of the surface, the vacuum for drawing the film into the mold can be applied for about 0.2 to about 5 seconds, or about 0.3 to about 3 seconds, or about 0.5 to about 1.5 seconds. For example, this vacuum can be such that it provides a negative pressure in the range of 10 mbar to 1000 mbar or in the range of 100 mbar to 600 mbar.

[0243] Depending on the desired sachet size, the mold for manufacturing the packet can have any shape, length, width, and depth. If desired, the size and shape of the mold can also be different from each other. For example, the final sachet volume can be about 5 ml to about 300 ml, or about 10 to 150 ml, or about 20 to about 100 ml, and the mold size can be adjusted accordingly.

[0244] The compositions can be selected from the group consisting of: light liquid and heavy liquid detergent compositions, powdered detergent compositions, dishwashing detergents for hand washing and / or machine washing; hard surface cleaning compositions, fabric softeners, detergent gels commonly used for clothing, and bleaches and clothing additives, shampoos and body washes, agricultural compositions, automotive compositions, aviation compositions, food and nutritional compositions, industrial compositions, livestock compositions, marine compositions, medical compositions, commercial compositions, military and paramilitary compositions, office compositions, and entertainment and park compositions, pet compositions, water treatment compositions, including cleaning and detergent compositions suitable for any such use.

[0245] Any suitable method for sealing the sachet and / or its individual compartments can be utilized. Non-limiting examples of such means include heat sealing, solvent welding, solvent or wet sealing, and combinations thereof. Optionally, only the area to be sealed is treated with heat or solvent. Heat or solvent can be applied by any method, typically to the closure material, and optionally only to the area to be sealed. If solvent or wet sealing or welding is used, it may be preferred to also apply heat. The wet sealing or solvent sealing / welding method can include selectively applying the solvent to the area between the dies, or to the closure material, such as by spraying or printing the solvent onto these areas, and then applying pressure to these areas to form a seal. A sealing roller and sealing belt as described above can be used, for example (optionally also providing heat).

[0246] The formed sachets can be cut by a cutting device. Cutting can be accomplished using any suitable method. Cutting can also be carried out continuously, and optionally at a constant speed, and optionally when horizontally positioned. The cutting device can be, for example, a sharp object, or a heated object, or a laser, whereby in the latter case, the heated object or laser 'burns' through the film / sealing area.

[0247] Dissolution and Disintegration Test (MSTM - 205)

[0248] According to the MonoSol Test Method 205 (MonoSol Test Method 205, MSTM205), which is a method known in the art, the film can be characterized or tested for dissolution time and disintegration time. See, for example, U.S. Patent No. 7,022,656. Equipment and Materials:

[0249] 600 mL beaker

[0250] Magnetic stirrer (Labline model 1250 or equivalent)

[0251] Magnetic stir bar (5 cm)

[0252] Thermometer (0 to 100 °C ± 1 °C)

[0253] Stainless steel template (3.8 cm × 3.2 cm)

[0254] Timer (0 - 300 seconds, accurate to the nearest second)

[0255] Polaroid 35 mm slide mount (or equivalent)

[0256] MonoSol 35 mm slide mount holder (or equivalent)

[0257] Distilled water

[0258] All membranes to be tested were conditioned in an environment of 23 °C / 35% relative humidity for at least 24 hours. For each membrane to be tested, three test samples were cut from the membrane sample (i.e., a 3.8 cm × 3.2 cm sample). If cutting from a membrane web, the samples should be cut from areas of the web that are evenly spaced along the transverse direction of the web. Then each test sample was analyzed using the following procedure.

[0259] Lock each sample in a separate 35 mm slide mount.

[0260] Fill a beaker with 500 mL of distilled water. Measure the water temperature with a thermometer and, if necessary, heat or cool the water to keep the temperature at approximately 5 °C (about 41 °F).

[0261] Mark the water column height. Place a magnetic stirrer on the holder base. Place the beaker on the magnetic stirrer, add a magnetic stir bar to the beaker, turn on the stirrer, and adjust the stirring speed until a vortex about one-fifth of the water column height is formed. Mark the vortex depth.

[0262] Fix the 35 mm slide mount in the alligator clip of the 35 mm slide mount holder such that the long end of the slide mount is parallel to the water surface. The depth adjuster of the holder should be set such that when dropped, the end of the clamp will be 0.6 cm below the water surface. One of the short sides of the slide mount should be next to the side of the beaker while the other short side is positioned directly above the center of the stir bar such that the membrane surface is perpendicular to the water flow.

[0263] In one motion, drop the fixed slide and clamp it into the water and start the timer. Disintegration occurs when the membrane ruptures. When all visible membrane is released from the slide mount, lift the slide out of the water while continuing to monitor the undissolved membrane fragments in the solution. Dissolution occurs when all membrane fragments are no longer visible and the solution becomes clear.

[0264] Results should include the following: complete sample identification; individual and average disintegration and dissolution times; and the water temperature at which the sample was tested.

[0265] The membrane disintegration time (I) and the membrane dissolution time (S) can be corrected to a standard or reference membrane thickness using the exponential algorithms shown in Equation 1 and Equation 2 below, respectively.

[0266] I 校正的 = I 测得的 × (reference thickness / measured thickness) 1.93 [1]

[0267] S 校正的 = S 测得的 × (reference thickness / measured thickness) 1.83 [2]

[0268] Tensile Strength Test

[0269] The water-soluble film whose tensile strength (i.e., the maximum stress, the stress required to rupture the film) is to be tested is analyzed as follows. The procedure includes determining the tensile strength according to ASTM D 882 ("Standard Test Method for Tensile Properties of Thin Plastic Sheeting") or an equivalent. Film data is collected using an INSTRON tensile testing device (Model 5544 tensile tester or equivalent). At least three test samples are tested in the machine direction (MD) (if applicable) for each measurement, and each test sample is cut with a reliable cutting tool to ensure dimensional stability and reproducibility. The film to be tested is conditioned in an environment of 23 ± 2.0 °C and 35 ± 5% relative humidity for at least 24 hours; the tensile strength test is also carried out in an environment of 23 ± 2.0 °C and 35 ± 5% relative humidity. For the tensile strength, a single film sheet sample with a width of 1" (2.54 cm) and a thickness of 76 μm is prepared. Then the sample is transferred to the INSTRON tensile testing machine for testing while minimizing the exposure in an environment of 35% relative humidity. The tensile testing machine is prepared according to the manufacturer's instructions, equipped with a 500N load cell, and calibrated. The correct grips and faces are installed (INSTRON grips, with a face of model 2702-032, the face is coated with rubber and has a width of 25 mm, or equivalent). The sample is installed in the tensile testing machine and analyzed to determine the tensile strength (i.e., the stress required to break the film).

[0270] The Young's modulus is determined from the slope of the linear fit of the stress-strain data in the strain range of 1 - 10%.

[0271] Elongation at Break Test

[0272] The determination of the elongation at break (i.e., the maximum strain or elongation at break) is based on ASTM D 882 ("Standard Test Method for Tensile Properties of Thin Plastic Sheeting") or an equivalent. Using a tensile testing device (Model 5544 tensile tester or equivalent) to collect film data. At least three test samples are tested in the machine direction (MD) (if applicable) for each measurement, and each test sample is cut with a reliable cutting tool to ensure dimensional stability and reproducibility. The film to be tested is conditioned in an environment of 23 ± 2.0 °C and 35 ± 5% relative humidity for at least 24 hours; the elongation at break test is also carried out in an environment of 23 ± 2.0 °C and 35 ± 5% relative humidity. For the determination of the elongation at break, a single film sheet sample with a width of 1" (2.54 cm) and a thickness of 1.4 ± 0.15 mil (about 35.6 ± 3.8 μm) is prepared. Then the sample is transferred to Testing is conducted on a tensile testing machine while minimizing exposure in an environment of 35% relative humidity. The tensile testing machine is prepared according to the manufacturer's instructions, equipped with a 500N load cell, and calibrated. The correct grips and faces ( grips, with faces of model number 2702 - 032, the faces being coated with rubber and having a width of 25 mm, or equivalents) are installed. The samples are installed into the tensile testing machine and analyzed to determine the breaking strain (i.e., in cases where Young's modulus is applicable).

[0273] Differential scanning calorimetry (DSC)

[0274] Testing is performed using a TA Instruments Q2000 differential scanning calorimeter (DSC) or equivalent, purged with nitrogen at 50 mL / min and using TZERO aluminum hermetic pans (available from TA Instruments) to avoid weight loss during temperature increase. The membrane samples to be tested are cut into small pieces to provide a total sample of approximately 3 - 5 mg suitable for the pans (e.g., approximately 3 stacked and cut membrane pieces). The DSC test is carried out by equilibrating the sample at -80 °C and then: (1) heating the sample at a rate of 10 °C / min to 75 °C to start generating the first DSC heating curve, (2) maintaining the sample at 75 °C for 15 minutes, (3) heating the sample from 75 °C to 200 °C at a rate of 10 °C / min and maintaining the sample at 200 °C for 1 minute to complete the first DSC heating curve, (4) cooling the sample to -80 °C at a rate of -5 °C / min to generate the DSC cooling curve, and optionally (5) heating the sample again to 200 °C at a rate of 10 °C / min to generate the second DSC heating curve. After generating the curves, transitions, melting, and crystallization attributable to the glass transition are assigned; the glass transition temperature, melting temperature, and crystallization temperature (Tg, Tm, and Tc respectively) are determined; and the melting or crystallization enthalpy is determined according to standard calorimetric analysis.

[0275] Water absorption

[0276] Water absorption is measured using a DVS (Dynamic Vapor Sorption) instrument. The instrument used is the SPS - DVS from ProUmid Corporation (model SPSx - 1μ - high load, with permeability kit). DVS uses gravimetric analysis to determine water absorption / desorption and is fully automated.

[0277] For the RH (relative humidity range) in the range of 0 - 98%, the accuracy of the system is ±0.6%, and at a temperature of 25 °C, the accuracy is ±0.3 °C. The temperature can be in the range of +5 to +60 °C. The microbalance in the instrument can resolve mass changes of 0.1 μg. Two replicates of each membrane are measured and the average water capacity value is reported.

[0278] For the specific conditions of the test, a 6-disk rotating table was used, which allowed the simultaneous testing of 5 membranes (1 disk was used as a reference for the microbalance and needed to remain empty).

[0279] Each disk had an aluminum ring with screws, and the screws were designed to fix the membrane. A piece of membrane was placed on the disk, and after gently stretching, the ring was placed on it, and the membrane was tightly fixed with screws, and the excess membrane was removed. The diameter of the membrane covering the disk surface was 80 mm.

[0280] The temperature was fixed at 20 °C. The relative humidity (RH) was set at 35% for 6 hours, and then gradually increased to 50% within 5 minutes. The RH was maintained at 50% for 12 hours. The total measurement duration was 18 hours.

[0281] The cycle time (=the interval time between measuring each disk) was set to 10 minutes, and the DVS recorded the relationship between each weight result and time, and automatically calculated the moisture % in the membrane as the relative mass change relative to the starting weight of the membrane, i.e., 10% reflected a 10% increase in the membrane weight relative to the starting membrane weight.

[0282] Capsule Compression Test

[0283] The following materials were used to analyze the ability of water-soluble membranes and / or sachets, which are characterized by or to be tested for their resistance to a mechanical compression strength of at least 300 N measured according to the compression test:[[]]

[0284] · Instron 5544 type (or equivalent);

[0285] · At least 5 water-soluble sachets or capsules to be tested; the membrane thickness was 76 μm; the sachets were pre-conditioned at 23 ± 1 °C and 50 ± 4% relative humidity for at least 24 hours;

[0286] · Zip-lock bags;

[0287] · Two flat plates (top plate: 10 kN maximum load T1223-1022 / bottom plate: 100 KN maximum load T489-74);

[0288] · Load cell (static load ±2 kN, maximum spindle torque 20 Nm, bolt torque 25 Nm, and weight 1.2 kg);

[0289] · Marker

[0290] · Allen wrench (6 mm)

[0291] Check the sachets for leaks and then place them in zip-lock bags (about 57 μm thick on each side). Seal the bags to minimize the air inside. Label the packages with the sample name and number.

[0292] Start the compression test method. The ramp speed should be 4 mm / sec.

[0293] Carefully place the sample (thermoformed side down) between the two plates, ensuring that the sachet is centered on the bottom plate. Move the capsules inside the sachet away from any edges.

[0294] Press start to run the test. When the two plates come together, the sachet will rupture. Record the compression strength and the location on the sachet where rupture occurs. Repeat this process for all samples.

[0295] Suitable behavior of the water-soluble film according to the present disclosure is marked by sachets having a compression strength value of at least about 300 N and less than about 2000 N.

[0296] Liquid Release Time Test MSTM-126

[0297] Use the following materials to analyze the water-soluble film and / or sachet characterized by or to be tested for delayed solubility according to the liquid release test as follows:

[0298] · A 2 L beaker and 1.2 liters of deionized (DI) water;

[0299] · The water-soluble sachet to be tested; film thickness is 76 μm; the sachet is pre-conditioned at 38 °C for two weeks;

[0300] · A thermometer;

[0301] · A wire cage;

[0302] · A timer.

[0303] Before running the experiment, ensure there is enough DI water to repeat the experiment five times and ensure that the wire cage and beaker are clean and dry.

[0304] The wire frame cage is a plastic-coated wire cage without sharp edges (4″ x 3.5″ x 2.5″ or about 10 cm x 9 cm x 6 cm) or equivalent. The wire gauge should be about 1.25 mm and the size of the wire openings should be 0.5 square inches (1.27 cm).

[0305] To set up the test, carefully place the water-soluble sachet into the cage without scratching the sachet on the cage and leave free space for the movement of the sachet. Do not tie the sachet tightly with the wire cage while ensuring that the sachet is fixed and will not come out of the cage. The orientation of the sachet in the cage should allow the sachet to have natural buoyancy (if any) (i.e., the side of the sachet that will float to the top should be placed facing up). If the sachet is symmetric, the orientation of the sachet is usually immaterial.

[0306] Next, fill the 2 L beaker with 1200 mL of 20 °C DI water. Water at other temperatures can be used for alternative methods.

[0307] Next, place the wire frame cage with the enclosed sachet into water. Ensure that the cage is 1 inch (2.54 cm) from the bottom of the beaker. Ensure that all sides of the sachet are completely submerged. Ensure that the cage is stable and will not move, and start the timer immediately after the sachet is placed in the water. The position of the cage relative to the water in the beaker can be adjusted and maintained in any suitable manner, such as by using a clamp fixed above the beaker and a rod attached to the top of the cage. The clamp can engage with the rod to fix the position of the cage, and the tension on the clamp can be reduced to lower the cage into the water. In an alternative to the clamp, other friction engagement means can be used, such as a collar with a set screw.

[0308] Liquid content release is defined as the first visual evidence of liquid leaving the submerged sachet.

[0309] Use the timer to record the time of liquid content release into the surrounding water (release time), with sachet failure (liquid release) as the stopping point.

[0310] For each membrane being tested, repeat this process five times with fresh DI water and fresh water-soluble sachets.

[0311] Unless otherwise reported, test a total of at least 3 sachets for each membrane sample type.

[0312] Accelerated Quantitative Residue Assessment

[0313] This test method is used for the quantitative assessment of membrane residues. The test consists of the steps detailed below.

[0314] Clean and Weigh Samples

[0315] Cut the membrane sample into 2″ x 2″ pieces and immerse them directly into a glass jar containing the liquid laundry detergent (LLD) of interest. Confirm that the LLD completely covers the membrane samples. Multiple membrane samples of the same type can be co-conditioned in the same LLD container. Cover the jar and add it to the conditioning environment for the desired time. For each membrane type to be studied, n = 3, and each n should contain two membrane squares.

[0316] Remove the membrane / LLD from the conditioning environment. First, remove the membrane samples from the LLD using forceps and let the LLD drain off, then wash briefly in methanol. Immediately wipe the membrane with a Kimwipe TM to remove residual LLD and methanol (the membrane should not appear greasy).

[0317] The test requires 100% cotton cloth with a diameter of 9 cm and the same color as Espresso Color. Assign a sample identifier (A B C) to the fabric circle and membrane combination.

[0318] Label the weighing boats and use the weighing boats to weigh and transport between test steps. Use address labels to mark the membranes, the detergents used, the time of the samples (7 days, 14 days... 70 days, etc.), the sampling conditions of the samples (38 °C, 80% RH), and the sample identifiers. Mark each sample in duplicate, and mark one "front" and the other "back" so that photos can be taken after the sample dries.

[0319] Weigh and record the weight of the weighing boat. Weigh and record the weight of the clean membrane. Weigh and record the dry weight of the fabric circle. Be sure to separate the fabric from the membrane in the weighing boat.

[0320] Test sample

[0321] Fill 4 1000 ml beakers with 800 mL of tap water at 15 °C.

[0322] Place the stir bar in the beaker, place it on top of the hot plate, and set a timer nearby.

[0323] Set the stirrer on the hot plate to stir at 300 RPM.

[0324] Cut 2 pieces of 2″x2″ membrane into 4 approximately equal pieces by halving, stack two pieces on top of each other, and halve again.

[0325] Place 8 membrane pieces (1″x1) into the water and start the countdown timer simultaneously.

[0326] Prepare a rubber collar for the Buchner funnel (inner diameter 9 cm), a vacuum flask, and a vacuum pump.

[0327] Place the fabric circle inside the Buchner funnel and ensure that all the holes are covered. Water can be used to moisten and stabilize the edges of the fabric.

[0328] When the countdown timer approaches 8 minutes (around 7:50), start the vacuum pump. When the timer approaches 8 minutes, stop the stirring function and start slowly pouring the liquid into the Buchner funnel.

[0329] Pour the dissolved membrane solution in the 1000 ml beaker directly into the center of the fabric and the funnel, not pouring too much so that the fabric filter at the bottom does not shift or the liquid cannot be filtered by the fabric.

[0330] After filtering all the liquid, check the beaker and the stir bar for visible residues. Use the water in the spray bottle and spray the sides of the beaker and the stir bar, rotate the beaker several times, and pour it into the Buchner funnel again.

[0331] If there is a large amount of visible residue, let the vacuum pump run for a longer time to draw out as much moisture as possible.

[0332] Once the vacuum pump is disconnected, use tweezers to lift one edge of the fabric and then the other edge. Clamp the two edges together with the tweezers and transfer to the weighing boat used for the original weighing and shipping.

[0333] Remove the hose from the vacuum flask and pour the filtered liquid in the vacuum flask into the sink. Reattach the hose.

[0334] Dry the sample overnight in an oven at 38 °C and 25% RH. (Minimum 6 hours)

[0335] Preparation and Testing of Samples

[0336] After the sample is dried, weigh and record the weight of the weighing boat and the membrane. Subtract the original weighing boat weight and the fabric weight to obtain the residue weight.

[0337] Report Test Results

[0338] After the sample is dried, weigh and record the weight of the weighing boat and the membrane. Subtract the original weighing boat weight and the fabric weight to obtain the residue weight.

[0339] These calculations describe the results.

[0340] Residue = Final - {Fabric (Initial) + Weighing Boat (Initial)}

[0341] Residue % = (Residue / Membrane (Initial)) * 100

[0342] Dissolution % = 100 - Residue %

[0343] A correction factor of 0.03 is added to the residue results. This accounts for typical fabric losses during filtration.

[0344] The various embodiments of the present disclosure will now be described in more detail below.

[0345] Examples

[0346] The following examples further illustrate the present disclosure.

[0347] Materials

[0348] Water-soluble films of the present disclosure and related aqueous solutions for forming water-soluble films are prepared using different water-soluble polyvinyl alcohol (PVOH) resins and water-soluble starches at different weight ratios and total solid load levels. Control films are also prepared in these studies.

[0349] The following starches were used in the various examples. Starch A is a cationic quaternary ammonium group modified starch with a low average molecular weight of about 10 3 -10 6In the range of g / mol, amylose is about 25 wt.%, and the modification level is 0.18 mol.%. The properties of starch A and other starches used in this study are shown in Table 2 below. Starch B is a starch modified with cationic quaternary ammonium groups, with a low average molecular weight in the range of about 10 3 -10 6 g / mol, containing no amylose (100% amylopectin), and the modification level is 0.18 mol.%. Starch C is hydroxyethylated corn starch (neutrally modified starch), with amylose of about 25 wt.%, and the modification level is less than about 3.0 mol.%. Starch D is an unmodified starch with amylose of about 25 wt.% and no modification. Starch E is an unmodified starch containing no amylose and no modification. Starch F is a waxy starch modified with octenyl succinic acid. Starch G is hydroxyethylated corn starch (neutrally modified starch), with an amylose content of about 25 wt.%, and the modification level is less than about 3.0 mol.%; the average molecular weight of starch G is higher than that of hydroxyethylated starch C. Starch H is a starch modified with cationic groups with amylose of about 25 wt.%. Starch J is a starch modified with cationic groups, containing no amylose (100% amylopectin), and the modification level is about 0.37 mol.%.

[0350] Table 2. Properties of different starches used in this study.

[0351]

[0352]

[0353] In each example, the following polyvinyl alcohol (PVOH) resins were used. Resin A is an anionically modified polyvinyl alcohol (PVOH), which is polyvinyl alcohol modified with monomethyl maleate (MMM), and the degree of modification is about 1.5 - 2.0 mol.%, and the degree of hydrolysis is 89 - 91 mol.%. Resin B is an anionically modified polyvinyl alcohol (PVOH), which is polyvinyl alcohol modified with methyl acrylate (MA), and the degree of modification is about 1 - 10 mol.%, and the degree of hydrolysis is 80 - 99 mol.%. Resin C is an anionically modified polyvinyl alcohol (PVOH), which is polyvinyl alcohol modified with monomethyl maleate (MMM), and the degree of modification is about 3.8 - 4.2 mol.%, and the degree of hydrolysis is 89 - 91 mol.%.

[0354] Two polyvinyl alcohol homopolymer resins, Resin D and Resin E, were also studied. Resin D is a commercially available polyvinyl alcohol homopolymer with a hydrolysis degree specification of 86.7% to 88.7%, a pH of 4.5 - 7, and a specific 4% solution viscosity at 20 °C of 11.4 - 14.5 cP. Resin E is a commercially available polyvinyl alcohol homopolymer with a hydrolysis degree specification of 87% to 89%, a pH of 5 - 7, and a specific 4% solution viscosity at 20 °C of 20.5 - 24.5 cP. However, the present inventors found that when the total solid content in the aqueous film-forming solution of all starches was tested to be 10 wt.% or higher, and the starch loading level was higher than 15 wt.% of the total solid content, the miscibility of these PVOH homopolymers with all starches was very poor and phase separation occurred with all starches. Neither Resin D nor E could be cast into a film in the case of high loading levels of starch.

[0355] Example 1

[0356] Water-soluble film with anionic polyvinyl alcohol (Resin A)

[0357] In this study, polyvinyl alcohol resin A modified with anionic groups (polyvinyl alcohol modified with monomethyl maleate (MMM)) and different types of starches, namely Starches A - E, shown in Table 2 respectively, were used, and different water-soluble films were prepared at different PVOH / starch weight ratios. The formulations of different water-soluble films with different PVOH to starch weight ratios are shown in Table 3 below and are described in terms of their "PHR starch". PHR starch is based on the total amount of 100 parts of PVOH and starch in the formulation, and can also be determined according to PHR starch = 100x starch wt％ / (starch wt％ +PVOH wt％ ). The polyvinyl alcohol used in each formulation in Table 3 is Resin A.

[0358] The method for preparing the water-soluble films and the related aqueous solutions used to form these films are described below. The phase stability, physical properties, and solubility of these water-soluble films were studied. The phase stability of the related aqueous solutions for each water-soluble film used to form the water-soluble films was also studied. The test results are shown in Table 4 below.

[0359] Table 3. Formulations of water-soluble films containing Resin A and various starches at different weight ratios. All percentages are percentages by dry weight of the film. The 33 PHR starch formulation was prepared with two polyvinyl alcohol resins, with Resin A being 37.33 wt.% and Resin C being 15.64 wt.% by weight of the dry film. The remaining formulations (containing 41, 45, 49, 55, and 80 PHR starch) were prepared with anionic polyvinyl alcohol resin A.

[0360]

[0361] In this study, blends of starch A and starch B in a 50:50 weight ratio were also used to prepare water-soluble films. The A:B blends were evaluated in 41 PHR and 49 PHR formulations (Samples 12 and 23 in Table 4, respectively). The phase stability of the aqueous solutions and the physical properties and water-soluble time of the water-soluble films were tested, and the test results are shown in Table 4 and are detailed below.

[0362] Method for preparing an aqueous solution for forming a water-soluble film

[0363] An aqueous solution for forming a water-soluble film is prepared by the following steps: 1) heating the water in a container to a temperature of about 85 °C; 2) adding plasticizers (glycerol and sorbitol) and an antifoaming agent while maintaining the water temperature at about 85 °C; 3) adding one of the starches in Table 2 to the water and mixing for about 1 hour to gelatinize and dissolve the starch, while adding an anti-blocking agent such as Hylon-V starch granules; 4) adding an additive (e.g., sodium metabisulfite) and mixing for about 20 minutes; 5) adding resin A (and resin C for the 33 PHR starch formulation) and mixing for about 1 hour; and 6) adding a surfactant and mixing for about 10 minutes. During the preparation, the water is maintained at a constant temperature of about 85 °C.

[0364] When preparing the aqueous solution, sufficient time, heat, and shear force are applied to the starch to gelatinize it and completely dissolve it in hot water, and further uniformly mix it with PVOH to form a miscible solution, or at least prevent phase separation between the PVOH and the water-soluble starch in the aqueous solution, and also form the resulting water-soluble film.

[0365] After mixing, the aqueous solution is stored overnight in an oven at 90 °C to degas. This also provides time for phase separation of the aqueous solution if the formulation is phase-unstable. After storing at 90 °C for 24 hours, the phase stability of each aqueous solution in the aqueous solution was evaluated by visual inspection, and the test results are shown in Table 4.

[0366] By weight of the aqueous solution, the total solid content of each aqueous solution is in the range of 28 - 35 wt.%. The total solid content of each aqueous solution formulation tested in this study is detailed in Table 4.

[0367] Method for preparing a water-soluble film

[0368] In this study, the samples in Table 4 that formed a single-phase aqueous solution or gel were then cast to form films to further test the physical properties of the resulting films. The method for forming a water-soluble film involves casting the aqueous solution or gel discussed above to a specified thickness onto a substrate; and drying the water in the cast aqueous solution or gel to form a water-soluble film.

[0369] In this study, a water-soluble film was formed by the following steps: setting the casting bed at a temperature of about 205°F (96°C); setting the doctor blade to a desired width (which varies between each formulation as the width is severely affected by viscosity); using a spray bottle to distribute a 1 wt.% release agent solution on the surface of the casting bed; metering an aqueous solution or gel into the casting trough; starting the robotic arm which translates the doctor blade across the bed to cast the aqueous solution onto the surface and spread it over the surface of the casting bed; drying to form a cast film; and removing the resulting cast film from the casting surface to form a free-standing film. The drying time was about 7 - 12 minutes or about 8.5 - 9.5 minutes. After standard conditioning at about 35% RH and 23°C for 24 hours, the mechanical and solubility properties of the resulting film were further tested.

[0370] Phase stability of aqueous solutions with anionic polyvinyl alcohol (Resin A)

[0371] The phase stability of the liquid solution mixtures of all formulations in Table 3 was tested, and the test results are shown in Table 4 below.

[0372] Table 4: Miscibility and total solids content of aqueous solutions of various formulations based on Resin A and different starches, as well as mechanical properties and solubility (at 10°C).

[0373]

[0374]

[0375] As shown in Table 4, starch A (cationic group-modified starch) at all starch load levels (41, 45, 49, 55, and 80 PHR) tested in this study formed a single-phase aqueous solution, where no phase separation or bulk phase separation was visually detected between starch A and Resin A (anionic group-modified PVOH), and no further formation of a high-viscosity gel occurred. By visual inspection, no further phase separation or bulk phase separation occurred between polyvinyl alcohol and starch in the aqueous solution during and after initial preparation and storage at about 90°C for at least 24 hours and at least about 48 hours. The test results indicate that at starch load levels up to about 80 PHR, Resin A and starch A are miscible or at least there is no bulk phase separation in the resulting aqueous solution. Additional tests by differential scanning calorimetry (DSC) showed a single Tg for the resulting water-soluble films with starch A at 41 PHR and 45 PHR, respectively.

[0376] An image of the single-phase solution of Sample 2 is as Figure 1AAs shown, these are representative images of single-phase solutions without phase separation or bulk phase separation for all stable and single-phase formulations described in this disclosure. These images were taken using a hot plate as a light box and a monochromatic filter on the camera. This method allows for easy identification of phase separation through the opacity of the solution. Solutions with different opacities are non-uniform and thus phase separation is carried out using a monochromatic color filter and a light box behind the sample, making it easy to distinguish phases when taking images.

[0377] Cationic starch B has the same type and degree of cationic quaternary ammonium group modification and a similar molecular weight as starch A, but does not contain amylose, while the amylose content of starch A is about 25 wt.%, but a single-phase aqueous solution is only formed at relatively low starch loading levels of 41 PHR (sample 20) and 45 PHR (sample 15) respectively, and these relatively low starch loading levels are still higher than the useful levels that ordinary starches can achieve. When the starch loading level is increased to 49 PHR, slight phase separation is observed in the resulting liquid solution mixture (sample 10). When the starch loading is further increased to 55 PHR, obvious phase separation is observed in the resulting solution (sample 4). Therefore, the test results indicate that the amylose content in cationic starch also affects the phase stability of the liquid solution mixture formed with anionic resin A.

[0378] Aqueous solutions were prepared using blends of cationic starch A and starch B at a 50:50 weight ratio at loading levels of 41 PHR and 49 PHR respectively. Based on the total weight of the starch, the resulting average amylose content was about 12.5 wt.%. In contrast, as described above, for liquid solution mixtures with starch B at the two loading levels, the resulting aqueous solutions are single-phase and no phase separation was observed.

[0379] For starch C modified with non-ionic groups (hydroxyethyl-modified starch with a modification degree lower than 3.0 mol.%), stable aqueous solutions are formed with resin A at relatively low starch loading levels of 41 PHR (sample 19) and 45 PHR (sample 14) tested respectively. At higher starch loading levels of 49 PHR (sample 8) and 55 PHR (sample 3), these liquid solution mixtures with starch C are unstable and phase separate into two layers. An image of the solution phase separation of sample 8 is as Figure 1B shown, which is a representative image of the solution phase separation of all unstable and phase-separated formulations described in this disclosure.

[0380] For unmodified starch D with 25 wt.% amylose, formulations with starch D form stable aqueous solutions with resin A only at relatively low starch load levels of 41 and 45 PHR, respectively. However, for formulations with higher load levels of starch D at 49 PHR and 55 PHR, respectively, the gels formed were observed to have a high viscosity and were thus difficult to subsequently form films. Without wishing to be bound by theory, it is believed that gel formation may be caused by the amount of unmodified amylose (25%) in unmodified starch D. Given that gel formation greatly increases the viscosity of the solution, this indicates that unmodified high amylose starches such as starch D are not preferred for film formation.

[0381] For unmodified starch, starch E contains no amylose, and formulations with starch D form stable aqueous solutions with resin A only at relatively low starch load levels of 41 and 45 PHR, respectively. However, for formulations with higher load levels of starch E at 49 PHR and 55 PHR, respectively, unstable liquid solutions were observed, and resin A and starch E phase-separated into two layers in both formulations. The phase separation behavior was observed to be similar to Figure 1B the solution phase separation images shown.

[0382] The test results of this study clearly show that the combination of the low molecular weight, amylose content, and type and degree of cationic modification of cationic starch A enables starch A to have good interaction with anionic resin A in aqueous solution and form a single-phase stable aqueous solution at a starch load level of up to 80 PHR (or a starch:PVOH weight ratio of up to 4:1). Further, even at a high starch load level of up to 80 PHR, no phase separation or bulk phase separation was observed in any aqueous solution and in the resulting water-soluble films containing resin A and starch A. However, for starch B with 0 wt.% amylose and a similar molecular weight and type and level of cationic modification, phase separation occurred with resin A at high starch load levels of 49 PHR or higher. To study the effect of amylose content on the phase stability of the resulting liquid solutions with the same formulations in Table 3, blends of starch A and starch B at a 50:50 weight ratio (resulting in a starch blend with 12.5 wt.% amylose) were also studied. The test results showed that formulations with the starch blend at 49 PHR formed a stable single-phase aqueous solution, and no phase separation or bulk phase separation was observed in the resulting aqueous solution and water-soluble film. The test results clearly show that the higher the amylose content in cationic starch, the better the interaction with anionic PVOH, and the more stable the phase of the aqueous solution at higher starch load levels.

[0383] The phase stability of formulations of unmodified starch D (25 wt.% amylose) was compared with that of unmodified starch E (0 wt.% amylose). The test results showed that at high starch load levels (such as 49 PHR and higher), unmodified starch with a high amylose content tended to form high-viscosity gels, while unmodified starch with a lower amylose content tended to phase-separate from PVOH. The solution made from the formulation of starch C modified with non-ionic groups was also unstable and tended to phase-separate at high starch load levels (such as 49 PHR or higher).

[0384] The phase stability of an aqueous solution of a blend of two anionic polyvinyl alcohol resins (resin A and resin C) with 33 PHR starch

[0385] Aqueous solutions of formulations of blends of two anionic polyvinyl alcohol resins (33.73 wt.% resin A and 15.64 wt.% resin C) with 33 PHR of different starches were prepared, and the phase stability was further tested. All 33 PHR starch formulations each formed a single-phase aqueous solution, in which there was no phase separation or bulk phase separation between the starch and the polyvinyl alcohol resin by visual observation, and no high-viscosity gel was formed. Further, the aqueous solution was phase-stable and there was no phase separation or bulk phase separation during and after initial preparation and storage in an oven at 90 °C for about 24 hours and about 48 hours.

[0386] The mechanical properties of the resulting water-soluble films

[0387] The mechanical properties and solubility of the resulting water-soluble films were tested, and the test results are shown in Table 4 above.

[0388] As shown in Table 4, at all starch load levels tested in this study, the films formed with cationic starch A had excellent maximum stresses higher than 20 MPa and higher breaking strains, and had the best maximum stress at high starch load levels of 49 PHR and 55 PHR compared to the films with other starches tested. At lower starch load levels of 41 PHR and 45 PHR, both cationic starch A and starch B, as well as starch C modified with non-ionic groups, showed fairly excellent maximum stresses and breaking strains.

[0389] In contrast, compared to the films of other starches tested in this study, the films prepared from unmodified starch D (25 wt.% amylose) showed the worst maximum stress and breaking strain. The films with unmodified starch E (0 wt.% amylose) showed acceptable maximum stresses and breaking strains at low starch load levels of 41 and 45 PHR respectively, but were worse than the maximum stresses and breaking strains of the modified starches A, B, and C.

[0390] Solubility of the resulting water-soluble film

[0391] The water solubility of the resulting different films was tested at 10 °C, and the test results are shown in Table 4. The cold water solubility of the resulting different films was tested at 5 °C, and the test results are as Figure 2 shown.

[0392] As shown in Table 4 and Figure 2 shown, the amylose content and the type and level of starch modification affect the cold water solubility of the corresponding films made from each starch. The films made from cationic starch A have a decreasing water solubility (longer dissolution time) at both 10 °C and 5 °C as the concentration of starch A in the film increases. The films made from cationic starch B at loading levels of 41 and 45 PHR show excellent cold water solubility at both 10 °C and 5 °C and have the best overall mechanical properties. The films made from non-ionic starch C also have excellent cold water solubility at both 10 °C and 5 °C. The films made from unmodified starch D show a slower cold water solubility at 10 °C.

[0393] Effect of amylose on solubility: For cationic starches, namely starch A (25 wt.% amylose), starch B (0 wt.% amylose), and blends of starch A and B with a similar type and degree of cationic modification (average 12.5 wt.% amylose), the lower the amylose content in the starch, the better the cold water solubility of the corresponding film (shorter dissolution time at both 10 °C and 5 °C). For unmodified starches, namely starch D (25 wt.% amylose) and starch E (0 wt.% amylose), the lower the amylose content in the starch, the faster the cold water solubility of the corresponding film at 10 °C.

[0394] Effect of modification on solubility: For starches with the same amylose content (25 wt.%), namely cationic starch A, non-ionic starch C, and unmodified starch D, starch modification enables the corresponding film to obtain a faster cold water solubility at 10 °C. For starches without amylose, namely cationic starch B and unmodified starch E, starch modification also enables the corresponding film to obtain a faster cold water solubility at 10 °C.

[0395] Example 2

[0396] Water-soluble film with anionic polyvinyl alcohol (resin B)

[0397] In this study, various formulations of polyvinyl alcohol and starch with different weight ratios were developed and described in Table 5 in terms of their "PHR" starch. PHR starch is based on the total amount of 100 parts of PVOH and starch in the formulation, and can also be calculated according to PHR starch = 100x starch wt％ / (starch wt％ +PVOHwt％ ) was determined. The polyvinyl alcohol used in all formulations in Table 4 is an anionically modified polyvinyl alcohol resin B (polyvinyl alcohol modified with methyl acrylate (MA)). All starches in Table 2 were studied separately in the formulations of Table 5.

[0398] Table 5. Water-soluble film formulations containing resin B and various starches at different PVOH / starch weight ratios. All percentages are by weight of the dry film.

[0399]

[0400] An aqueous solution for forming a water-soluble film was prepared by dissolving the components in the formulations of Table 5, in a manner similar to that disclosed above in Example 1. The water-soluble films in this study were made by casting the corresponding aqueous solutions, in a manner similar to that disclosed above in Example 1.

[0401] As shown in Table 6 below, the mechanical and solubility properties of the resulting films were further tested.

[0402] Phase stability of aqueous solutions with anionic polyvinyl alcohol (resin B)

[0403] During storage of the aqueous solution at 90 °C for at least about 24 hours, its phase stability was studied by visual inspection. The test results are shown in Table 6 below.

[0404] Table 6. Phase stability of aqueous solutions and mechanical properties and solubility of the resulting water-soluble films with resin B.

[0405]

[0406] As shown in Table 6, the liquid solution mixture of Sample 25 made with 49 PHR of non-ionic starch C was unstable, and phase separation of PVOH and starch occurred in the liquid solution. All other aqueous solutions with resin B were phase-stable at the time of initial preparation and during and after storage at 90 °C for at least about 24 hours.

[0407] Mechanical properties of the resulting water-soluble films

[0408] The mechanical properties of the resulting water-soluble films were tested, and the test results are shown in Table 6 above.

[0409] As shown in Table 6, the films formed with cationic starch A have a relatively high maximum stress above 20 MPa and a relatively high fracture strain at both starch loading levels of 43 and 49 PHR, which is beneficial for packaging applications. At a starch loading level of 49 PHR, the films made with cationic starch A (25 wt.% amylose), cationic starch B (0 wt.% amylose), and unmodified starch E (0 wt.% amylose) all exhibit relatively high maximum stress and maximum fracture strain, which is beneficial for packaging applications, while the film made with unmodified starch D shows the lowest mechanical properties. The test results indicate that unmodified starches with a high amylose content produce water-soluble films with relatively low mechanical properties.

[0410] The water solubility of the obtained water-soluble films

[0411] The water solubility of the obtained different films was tested at 10 °C, and the test results are shown in Table 6 above.

[0412] As shown in Table 6, it is shown that the film (Sample 27) made with unmodified starch D (25 wt.% amylose) is insoluble in water at 10 °C. This again indicates that starch D (unmodified, high amylose) is not preferred for water-soluble films. However, this may be applied to fields other than water-soluble films, such as oxygen barrier films for packaging applications.

[0413] Example 3

[0414] Optical micrographs of the stretched and unstretched films of Sample 31

[0415] In this study, starch F (octenyl succinic anhydride (OSA)-modified starch) was investigated using the formulations in Table 7, and the prepared film samples were labeled as Sample 31.

[0416] Table 7. Water-soluble film formulations containing resin B and 33 PHR starch F. All percentages are by weight of the dry film.

[0417] Composition (WT.%) 33 PHR Starch (Sample 31) Resin B 44.00％ Starch F 21.50％ Sorbitol 8.46％ Glycerol 19.35％ Sodium metabisulfite 0.09％ Defoaming 0.46％ Other Additives 3.63％

[0418] As shown in Table 5, Sample 31 had approximately 33 PHR of starch F (octenyl succinic anhydride (OSA)-modified starch) in its formulation. An aqueous solution of this formulation and the resulting film were prepared by a method similar to the method disclosed in Example 1. The resulting film had many undesirable properties. Over time, the starch in the film was oxidized, which led to roll sticking, and the color of the film changed from transparent to brown. The film also exhibited significant strain whitening when stretched. Micrographs of the stretched and unstretched films are shown in Figure 3. Without wishing to be bound by theory, it is believed that the strain whitening may be due to (solid) phase separation of PVOH and starch in the range of 10 - 100 μm. In other PVOH / starch water-soluble films prepared in this study, this strain whitening behavior was not observed. The test results can indicate that in water-soluble film applications, a high degree of non-polarity and a large amount of OSA modification of starch are not preferred.

[0419] Example 4

[0420] Capsules with sachets made of water-soluble film

[0421] Capsules with sachets made of the water-soluble films prepared in Examples 1 and 2 were prepared. The liquid composition was encapsulated in each of the sachets. The liquid release time (LRT) of the sachets was tested according to the liquid release test described above, and the test results are shown in Table 8 below. As described above, the PHR level of starch is based on the total content of starch and PVOH resin.

[0422] All capsules were molded at a draw ratio of 2.5 (the draw ratio is calculated by the ratio of the final area of the film perpendicular to the draw direction to the original area), and the samples were tested at room temperature and in deionized (D.I.) water. Capsules 1_4 were tested with a first liquid laundry detergent (LLD 1). Only capsule 5 (Sample 7 in Example 1) was tested with a second LLD (LLD 2) different from the first liquid laundry detergent. The capsules were tested within one week of the film-to-capsule conversion.

[0423] Table 8. Liquid release times of capsules with sachets made of different water-soluble films.

[0424]

[0425] As shown in Table 8, the liquid release times of all capsules 1 - 5 made from starch / PVOH films exceeded the 30 - second threshold required by regulatory agencies for liquid laundry detergents. The liquid release times for all capsules were at least 2 minutes but less than 5 minutes. The liquid release time of capsule 5 made from the film of sample 7 in Example 1 (with 51 PHR resin A and 49 PHR starch A) was significantly longer, but this may be due to the use of a different LLD. There was no significant difference between capsule 3 (41 PHR starch A) and capsule 4 (41 PHR starch C), although the starch C formulation is generally more water - soluble.

[0426] Example 5

[0427] Compressive strength of the capsules

[0428] The compressive strength of the capsules with sachets made from the films in Examples 1 and 2 was tested using the above - mentioned capsule compression test. The test results are shown in Table 9.

[0429] Table 9. Compressive strength of the capsules

[0430]

[0431] In this study, early seal failure was defined as failure < 25% of the maximum compressive strength in each sample group. The matte surface of the film refers to the surface of the contact strip and the mold release agent transferred to the film, which sometimes causes a higher seal failure.

[0432] The compressive strength of the capsules depends on the mechanical properties of the film and the seal strength. The average compressive strength of all capsules in this study was in the range of approximately 600 - 1500 N, which is much higher than the typical industry requirement of 300 N. The formulations that achieved the best matte - to - matte seal were capsules 1, 7, 8, and 9 - 10. Seal failure could usually be detected by applying pressure to the capsules by hand.

[0433] Example 6

[0434] Residue test

[0435] Residue tests were performed on the water - soluble films prepared in Examples 1 and 2 according to the above - mentioned accelerated quantitative residue assessment test method. The test results are shown in Table 10 below.

[0436] Table 10. Residue tests on the films prepared in Examples 1 and 2 by scale.

[0437] Film Pilot Scale Film Starch PHR Starch Residue % Dissolution % 1 B Sample 29 Example 2 41 Starch A 2.45％ 97.55％ 2 B Sample 13 Example 1 45 Starch A 18.49％ 81.51％ 3 B Sample 7 Example 1 49 Starch A 9.68％ 90.32％ 4 B New Sample 32 52 Starch A 10.00％ 90.00％ 5 B New Sample 33 80 Starch A 20.72％ 79.28％ 6 B Sample 9 Example 1 49 Starch B 2.60％ 97.40％ 7 L Sample 18 Example 1 41 Starch A 5.73％ 94.27％ 8 L Sample 19 Example 1 41 Starch C 5.62％ 94.38％ 9 L Sample 30 Example 2 43 Starch A 6.82％ 93.18％ 10 S Sample 18 Example 1 41 Starch A 20.34％ 79.66％

[0438] All films were tested without exposure to liquid laundry detergent (LLD). LLD exposure can significantly alter the residue results. All water used was tap water at 14 °C. In Table 10 above, B refers to bench-scale cast film samples; L refers to pilot-scale cast film samples; and S refers to semi-finished test cast film samples.

[0439] As shown in Table 10, the residue of Film 6 (49 PHR starch B) was 7% less than the residue of Film 3 (49 PHR starch A). The data presented in Example 1 confirm that cationic starch A (25 wt.% amylose) is less water-soluble than cationic starch B (0 wt.% amylose). Although Film 4 has 3 more PHR of starch A than Film 3, the residues are very similar. Despite the different starches, there is no significant difference in the residues of Films 7 and 8. The residue of Film 10 is much higher than the residue of Film 7. This may be due to different processing conditions.

[0440] Example 7

[0441] Differential scanning calorimetry (DSC) thermal analysis of selected films

[0442] Some bench-scale cast film samples prepared in Examples 1 and 2 were further analyzed to measure the glass transition temperature (Tg), melting temperature (Tm), crystallization temperature (Tc), and melting and crystallization enthalpies using differential scanning calorimetry (DSC). The results of the thermal analysis tests are shown in Table 11 below.

[0443] Table 11: Summary of DSC data collected for comparison of bench-scale cast starch / PVOH films with a commercial PVOH (Resin A) control film.

[0444]

[0445] Differential scanning calorimetry (DSC) measurements were performed on various starch / PVOH films. The melting enthalpy and crystallization enthalpy of the starch / PVOH blend films were lower than those of the control film (a commercial polyvinyl alcohol (Resin A) film without starch). This indicates that the starch / PVOH films have a lower crystallinity compared to existing commercial films without water-soluble starch. Part of the reason may be the different process conditions at the bench and production scales (i.e., the films typically have a lower crystallinity at the bench scale); however, it is expected that the crystallinity of starch will be lower than that of PVOH. Interestingly, some starches seem to reduce crystallinity more than others. For example, at two different loading levels, the crystallinity of the starch B / resin A films (films 9, 10, 12, and 13) was much higher than that of the starch D / resin A films (films 7, 8, 16, and 17). Among the films tested in this study, films 14 and 15 with starch A and resin B exhibited the highest crystallinity. This indicates that the type of starch used in the formulation can be used to adjust the crystallinity of the final film. This is beneficial because increasing crystallinity improves mechanical properties but may shorten the dissolution time. Therefore, by designing the crystallinity based on the starch selection, the crystallinity can be optimized to balance the effects of dissolution time and mechanical properties. Further, all tested samples showed a single Tg.

[0446] Example 8

[0447] DVS analysis of the selected formulations

[0448] Dynamic vapor sorption (DVS) analysis was performed on some of the samples prepared in Examples 1 and 2, and the test results are shown in Table 12.

[0449] Table 12: Dynamic vapor sorption (DVS) data for measuring the water absorption of the films at 23 °C.

[0450]

[0451] The dynamic vapor sorption (DVS) data show the water uptake and retention at a specific humidity. In this experiment, the relative humidity (RH) was ramped up to 80% RH in 10 steps and then decreased to 0% in the next 10 steps. The RH value was held constant until each sample reached equilibrium moisture, and the moisture percentage was determined by the mass gain. The moisture percentage was calculated based on the minimum mass measured after the film was equilibrated at 0% RH and 25 °C for 16 hours.

[0452] Furthermore, Figure 4Also shown are the test results of the dynamic vapor sorption of Film 5 (59 PHR Resin A and 41 PHR Starch A) and Film 6 (59 PHR Resin A and 41 PHR Starch C) after reaching equilibrium at 23 °C under specified moisture, and compared with the control film of Control M8630 (commercial film with Resin B without water-soluble starch). Figure 5 Shown are the test results of the dynamic vapor sorption over time of Films 1 - 3, 5, 22 and the control film containing Resin A (containing Resin A without water-soluble starch). At Figure 5 about 80 - 90 hours, the order of the data plots from top to bottom is as follows: Film 1, Film 3, Film 2, Film 22 / Film 5 (essentially overlapping), Control.

[0453] Table 12 and Figure 4 and 5 The experimental results in show that the difference in water absorption among the different PVOH / starch films in this study is not significant. The DVS water absorption of Film 5 and Film 6 is very similar to each other at all measured relative humidities, and slightly lower than the DVS water absorption of the Control MonoSol M8630 film at 50% or higher relative humidity.

[0454] However, it can be clearly seen from Figure 5 that when compared with the control film containing Resin A, the behavior of all PVOH / starch films is very different. For this control at each new RH value, the weight percentage of water in the film rises sharply and then falls. Without being bound by any particular theory, it is believed that this is due to the crystallization of the amorphous regions of the film resulting in a reduced water absorption capacity of the film. This effect was not observed in any of the PVOH / starch films, indicating that no additional crystallization occurs at room temperature as the RH% increases.

[0455] Example 9

[0456] Water-soluble films containing PVOH, starch, and adjuvant are prepared according to the methods described herein, and the amounts are shown in Table 13. As shown in Table 13, the total starch content of each composition is 0, 10, 20, 30, or 40 PHR. The PVOH in all films is Resin A. The starch is one of Starch A - E, G, H, or J, or a 1:1 (wt:wt) blend of two cationic starches with the total starch amount as listed in the table below.

[0457] Table 13

[0458] Composition 0 PHR Starch 10 PHR Starch 20 PHR Starch 30 PHR Starch 40 PHR Starch PVOH 73.75％ 66.38％ 59.00％ 51.63％ 43.25％ Starch 0.00％ 7.38％ 14.75％ 22.13％ 28.83％ Sorbitol 5.30％ 5.30％ 5.30％ 5.30％ 5.30％ Glycerol 18.17％ 18.17％ 18.17％ 18.17％ 18.17％ Sodium metabisulfite 0.74％ 0.74％ 0.74％ 0.74％ 0.74％ Defoaming 0.02％ 0.02％ 0.02％ 0.02％ 0.02％ Anti - sticking 1.73％ 1.73％ 1.73％ 1.73％ 1.73％ Surfactant 0.29％ 0.29％ 0.29％ 0.29％ 0.29％

[0459] The breaking strain of the films of the formulations listed in Table 13 (including Starch A, C, E, or G as the starch) was measured according to the methods described herein; the results are shown in Table 14.

[0460] Table 14: Fracture strain values of various PVOH / starch-containing films.

[0461]

[0462] Compared with the same films containing starch E (unmodified starch) or starch A (cationic starch), the films containing starch C (hydroxyethyl-modified starch) remain flexible to a greater extent at a starch loading increased to 40 PHR. Compared with other same films containing starch G, the films containing starch C also remain flexible to a greater extent at a starch loading increased to 40 PHR, where starch G is a hydroxyethyl-modified starch with an average molecular weight higher than that of starch C.

[0463] The Young's modulus of films having the formulations listed in Table 13 and comprising the starches or starch blends listed in Table 15 was measured according to the methods described herein.

[0464] Table 15: Young's modulus values of various PVOH / starch-containing films (in N / mm 2 units).

[0465]

[0466] Films containing unmodified starch exhibit an increase in Young's modulus with an increase in starch loading (i.e., an increase in the starch:PVOH ratio), indicating that the films become more rigid with an increase in starch content. Films containing starch G, i.e., hydroxyethylated starch, also exhibit an increase in Young's modulus with an increase in starch content, although increasing the content of hydroxyethylated starch with an average molecular weight lower than that of starch G does not have the same effect. Specifically, increasing the loading of cationically modified starch, whether as a single starch or as a blend of two cationic starches, generally does not increase the Young's modulus of the resulting films.

[0467] As used herein, the term "gelatinization %" refers to the maximum water solubility after starch gelatinization, i.e., the maximum weight percentage of starch dissolved in water under heated cooking conditions, such as by directly injecting steam and mixing in water at about 95 °C for about 30 minutes.

[0468] As used herein and unless otherwise specified, the term "water-soluble film" refers to any film having a thickness of about 1.5 mils (about 0.038 mm) and having a dissolution time in water at a temperature of about 20 °C (68 °F) of 300 seconds or less according to the MonoSol test method MSTM-205 as set forth herein. For example, at a temperature of about 80 °C, about 70 °C, about 60 °C, about 50 °C, about 40 °C, about 20 °C, about 10 °C, or about 5 °C, the dissolution time can optionally be about 300 seconds or less, about 250 seconds or less, about 200 seconds or less, about 100 seconds or less, about 60 seconds or less, or about 30 seconds or less. At a temperature of about 40 °C (104 °F), the dissolution time can optionally be about 300 seconds or less. In embodiments where the dissolution temperature is not specified, the water-soluble film has a dissolution time of 300 seconds or less at a temperature not exceeding about 80 °C.

[0469] As used herein and unless otherwise specified, the term "cold water-soluble" refers to any film having a thickness of about 1.5 mils (about 0.038 mm) and having a dissolution time at 10 °C of 300 seconds or less as determined according to MSTM-205. For example, at a temperature of about 10 °C, the dissolution time can optionally be 200 seconds or less, 100 seconds or less, 60 seconds or less, or 30 seconds.

[0470] As used herein and unless otherwise specified, the term "5 °C cold water-soluble" refers to any film having a thickness of about 1.5 mils (about 0.038 mm) and having a dissolution time at 5 °C of 300 seconds or less as determined according to MSTM-205. For example, a water-soluble film having a thickness of 1.5 mils (about 38 μm) can have a dissolution time in water at a temperature of about 5 °C of 300 seconds or less, 200 seconds or less, 100 seconds or less, 60 seconds or less, 30 seconds or less, 20 seconds or less.

[0471] As used herein, "comprising" means the different components, ingredients, or steps that can be used together in practicing the present disclosure. Accordingly, the term "comprising" encompasses the more restrictive terms "consisting essentially of" and "consisting of". The compositions of the present invention can comprise, consist essentially of, or consist of any of the essential and optional elements disclosed herein. The present invention illustratively disclosed herein can be practiced appropriately in the absence of any element or step not specifically disclosed herein.

[0472] All percentages, parts, and ratios referred to herein are, where appropriate, based on the total dry weight of the water-soluble film, total solids content, or article of the present disclosure, and all measurements are made at about 25 °C unless otherwise specified.

[0473] All ranges set forth herein include all possible subranges of the range and any combination of such subranges of the range. Unless otherwise stated, by default, a range includes the recited end values. In the case of a range of values being provided, it is understood that each intermediate value between the upper and lower limits of the range and any other recited value or intermediate value within the stated range is covered by the present disclosure. The upper and lower limits of these smaller ranges may independently be included in the smaller ranges and are also covered by the present disclosure, subject to any expressly excluded limits within the stated range. In the case where the stated range includes one or both of the limiting values, ranges excluding any one or both of the included limiting values are also contemplated as part of the present disclosure.

[0474] It is specifically contemplated that for any numerical value described herein, such as as a parameter of the described subject matter or as part of a range associated with the described subject matter, an alternative that forms part of the description is a functionally equivalent range around the specific numerical value (e.g., for a dimension disclosed as “20 cP,” an alternative embodiment contemplated is “about 40 cP”). Similarly, a numerical value described with “about” specifically includes alternative embodiments of the specific numerical value itself (e.g., for an endpoint described as “about 40,” an alternative embodiment contemplated is “40”).

[0475] As used herein and unless otherwise stated, the terms “wt. %” and “wt%” are intended to refer to the composition of the identified element in “dry” (non - aqueous) parts by weight of the entire water - soluble film, total solids content, or article.

[0476] As used herein and unless otherwise stated, the term “PHR” (“phr”) is intended to refer to the composition of the identified element in parts per hundred parts of the total polymer amount or per hundred parts of the total amount of PVOH and water - soluble starch in the water - soluble film or aqueous solution.

[0477] The term “Renewable Carbon Index (“RCI”)” refers to the fraction (or percentage) of carbon atoms derived from feedstocks other than petroleum or natural gas in the average structure of, for example, an anionic surfactant, a hydrophilic synthetic detergent, a hydrophobic synthetic detergent, or optionally a solvent. Typically and desirably, since materials present in nature are used, or feedstocks derived from sustainable sources such as plants, fungi, or algae, products of bacterial fermentation processes, or processed products of plant, fungal, or algal - derived biomass are used, the RCI will generally exceed 0.75 or “75%” when such components of the water - soluble film are made of natural materials or produced in a sustainable manner. The main challenge in formulating water - soluble films with a desirable high RCI is to select several suitable materials that are both economically viable and deliver performance as good as or better than traditional products.

[0478] Starch is a material with an ideal high RCI and is derived from raw material sources such as plants.

[0479] As used herein, the term "substantially" or "essentially" means mainly but not necessarily completely the specified substance, such as an amount of at least about 80 wt.%, at least about 85 wt.%, at least about 90 wt.%, at least about 91 wt.%, at least about 92 wt.%, at least about 93 wt.%, at least about 94 wt.%, at least about 95 wt.%, at least about 96 wt.%, at least about 97 wt.%, at least about 98 wt.%, at least about 99 wt.% or at least about 99.5 wt.% of the specified substance or within the range of about 80 - 100 wt.%, about 90 - 100 wt.%, about 95 - 100 wt.%, about 96 - 100 wt.%, about 97 - 100 wt.%, about 98 - 100 wt.% or about 99 - 100 wt.% of the specified substance.

[0480] As used herein, the term "bulk phase separation" means a phase separation where the phase domains are less than about 2000 μm, or less than about 1000 μm, or less than about 900 μm, or less than about 800 μm, or less than about 700 μm, or less than about 600 μm, or less than about 500 μm, or less than about 400 μm, or less than about 300, or less than about 200 μm, or less than about 100 μm, or less than about 50 μm, or less than about 10 μm or even less than about 1 μm.

[0481] As used herein, the term "consisting essentially of" limits the scope of the claim to the specified materials or steps and those materials or steps that do not materially affect the basic and novel characteristics of the claimed invention.

[0482] As used herein, the term "consisting of" does not include any element, step or ingredient not specified in the claim.

[0483] As used herein, the words "include" and its variants are intended to be non - restrictive, such that the listing of items in a list is not used to exclude other similar items that may also be useful in the materials, compositions, devices and methods of the technology of the present invention. Similarly, the terms "can" and "may" and their variants are intended to be non - restrictive, such that the recitation that an embodiment can / may include certain elements or features does not exclude other embodiments of the technology of the present invention that do not include these elements or features.

[0484] As used herein, the term "comprising" is used when referring to a composition, method, and its corresponding components essential to the present invention, but is still open for including unspecified elements, whether necessary or not. Although the open-ended term "comprising" is used herein as a synonym for non-limiting terms such as "including", "containing", or "having" to describe and claim embodiments of the technology of the present invention, embodiments may alternatively be described using more restrictive terms such as "consisting of" or "consisting essentially of". Thus, for any given embodiment of narrative material, components, or process steps, the technology of the present invention also specifically includes embodiments consisting of or consisting essentially of such material, components, and processes, excluding additional material, components, and processes (for consisting of), and excluding additional material, components, and processes that affect the significant characteristics of the embodiment (for consisting essentially of), even if such additional material, components, and processes are not explicitly recited in this application.

[0485] As used herein, the term "consisting essentially of" refers to those elements required for a given embodiment. The term permits the presence of additional elements that do not substantially affect the basic and novel or functional characteristics of that embodiment of the present invention.

[0486] The term "consisting of" refers to the compositions, methods, and their corresponding components as described herein, which compositions, methods, and their corresponding components do not include any element not recited in the description of that embodiment.

[0487] As used herein, unless otherwise specified, all component percentages are by weight of the total composition. Unless otherwise specified, open ranges include endpoints and include all different values and further divided ranges within the entire range. Thus, for example, a range of "A to B" or "about A to about B" includes A and B. The disclosure of specific values and ranges of values for particular parameters (such as temperature, molecular weight, weight percentage, etc.) does not exclude other values and ranges of values used herein. It is contemplated that two or more specific exemplified values of a given parameter can define the endpoints of a range of values of the parameter that may be claimed. For example, if parameter X is exemplified herein as having a value of A and is also exemplified as having a value of Z, it is contemplated that parameter X can have a range of values from about A to about Z. Similarly, it is contemplated that the disclosure of two or more ranges of values of a parameter (whether such ranges are nested, overlapping, or distinct) encompasses all possible combinations of ranges of values that may be claimed using the endpoints of the disclosed ranges. For example, if parameter X is exemplified herein as having values within the ranges of 1-10, 2-9, or 3-8, it is also contemplated that parameter X can have other ranges of values, including 1-9, 1-8, 1-3, 1-2, 2-10, 2-8, 2-3, 3-10, and 3-9.

[0488] As used herein, "a" and "an" indicate the "at least one" presence of an item; multiple such items may be present where possible.

[0489] When applied to a value, "about" indicates that there is some slight imprecision in the calculation or measurement (to some degree approaching the precision of the value; approximate or reasonably close to the value; close). For some reason, if the imprecision provided by "about" is not understood in this ordinary sense in the art, then "about" as used herein means at least the variation that may be caused by the ordinary methods of measuring or using such a parameter. As used herein, when used in conjunction with a value, the term "about" can refer to a variation of ±10% from the value. Except in operating examples or where otherwise indicated, in all cases, all numbers representing amounts of ingredients or reaction conditions used herein should be understood to be modified by the term "about".

[0490] As used herein, the terms "substantially free", "essentially free", or "basically free" as used in reference to a specific component can mean that any component present constitutes less than 10% by weight, such as less than 9% by weight, less than 8% by weight, less than 7% by weight, less than 6% by weight, less than 5% by weight, less than 4% by weight, less than 3% by weight, less than 2% by weight, less than 1% by weight, less than 0.5% by weight, or less than 0.1% by weight.

[0491] As used herein and unless otherwise indicated, the term "portion" refers to a range greater than 0% and less than 100%.

[0492] As used herein, the term "room temperature" can refer to a temperature in the range of 25°C ± 5°C or 25°C ± 3°C.

[0493] As used herein, the term "substantially unchanged" means that the characteristic value of a process (e.g., a reaction or heating) changes by less than 20%. In an embodiment, "substantially unchanged" means that the change in the characteristic value is less than 20%, less than 10%, less than 5%, less than 1%, less than 0.5%, or less than 0.1% relative to the characteristic value before treatment.

[0494] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0495] As used herein and unless otherwise indicated, in the context of a range, the term "between" includes the endpoints of the range.

[0496] As used herein, the abbreviations "e.g." or "i.e." indicate non-limiting examples. Thus, the abbreviations "e.g." or "i.e." are synonymous with the term "for example". In the context of use herein, the terms "example" and "such as" (especially when followed by a list of terms) are merely exemplary and illustrative and should not be regarded as exclusive or comprehensive.

[0497] The foregoing description has been given for clarity of understanding only and should not be understood to impose unnecessary limitations, as modifications within the scope of the present disclosure may be apparent to those of ordinary skill in the art.

[0498] All patents, publications, and references cited herein are hereby incorporated by reference in their entirety. In the event of a conflict between the present disclosure and the incorporated patents, publications, and references, the present disclosure shall prevail.

Claims

1. A water-soluble film, comprising: Water-soluble polyvinyl alcohol (PVOH); and Water-soluble starch, wherein the gelatinization % of the water-soluble starch is at least about 5 wt.%, wherein the water-soluble starch is present in an amount in the range of about 5-65 wt.% based on the weight of the water-soluble film, and wherein the PVOH and the water-soluble starch are miscible in the water-soluble film or the phase domains are less than 2000 μm.

2. The water-soluble film according to claim 1, wherein the water-soluble polyvinyl alcohol (PVOH) is soluble in water at a temperature of about 60 °C or lower in about 60 minutes, or is soluble in water at a temperature of about 60 °C in about 60 minutes, is soluble in water at a temperature of about 40 °C in about 60 minutes, is soluble in water at a temperature of about 20 °C in about 60 minutes or is soluble in water at a temperature of about 10 °C in about 60 minutes.

3. The water-soluble film according to claim 1, wherein the water-soluble polyvinyl alcohol (PVOH) is soluble in water at a temperature of about 40 °C or lower in about 10 minutes.

4. The water-soluble film according to claim 1, wherein the water-soluble film is a free-standing film.

5. The water-soluble film according to claim 1, wherein the renewable carbon index (RCI) of the water-soluble film is higher than about 50%.

6. The water-soluble film according to claim 1, wherein the water-soluble starch comprises substantially gelatinized starch.

7. The water-soluble film according to claim 1, wherein the gelatinization % of the water-soluble starch is at least about 10 wt.%.

8. The water-soluble film according to claim 1, wherein the gelatinization % of the water-soluble starch is at least about 15 wt.%.

9. The water-soluble film according to claim 1, wherein the average molecular weight of the water-soluble starch is about 10 3 -10 7 g / mol or about 10 3 -10 6 g / mol.

10. The water-soluble film according to claim 9, wherein the average molecular weight of the water-soluble starch is in the range of about 10 4 -10 5 g / mol.

11. The water-soluble film according to claim 1, wherein the amylose content comprised in the water-soluble starch is in the range of 0-50 wt.% of the water-soluble starch.

12. The water-soluble film according to claim 1, wherein the Brookfield viscosity of a 5 wt.% aqueous solution of the water-soluble starch at about 20 rpm and about 87.8 °C is in the range of about 1-2000 cP.

13. The water-soluble film according to claim 1, wherein the Brookfield viscosity of a 5 wt.% aqueous solution of the water-soluble starch at about 20 rpm and about 87.8 °C is in the range of about 2-100 cP.

14. The water-soluble film according to claim 1, wherein the water-soluble starch is present in an amount in the range of about 20-60 wt.% based on the weight of the water-soluble film.

15. The water-soluble film according to claim 1, wherein the water-soluble film dissolves in water at a temperature of about 15 °C, and as determined by the accelerated quantitative residue evaluation test method, the residue at the specified temperature is less than 5.0 wt.% based on the weight of the water-soluble film.

16. The water-soluble film according to claim 1, wherein the water-soluble starch comprises unmodified starch.

17. The water-soluble film according to claim 1, wherein the water-soluble starch comprises starch modified with non-ionic groups, and the modification level is in the range of about 0.1 - 10 mol%.

18. The water-soluble film according to claim 17, wherein the water-soluble starch comprises the starch modified with non-ionic groups, and the modification level is in the range of about 1 - 5 mol%.

19. The water-soluble film according to claim 1, wherein the water-soluble starch comprises starch modified with cationic groups, and the degree of modification is in the range of about 0.01 - 10 mol%.

20. The water-soluble film according to claim 19, wherein the water-soluble starch comprises the starch modified with cationic groups, and the degree of modification is in the range of about 0.1 - 1 mol%.

21. The water-soluble film according to claim 20, wherein the cationic group-modified starch comprises a cationic quaternary ammonium group-modified starch having the structure of formula A, wherein R1, R2 and R3 are each independently H or C1-C 10 alkyl or C1-C 10 hydroxyalkyl, wherein R4 is a straight-chain or branched C1-C 10 alkylene or C1-C 10 hydroxyalkylene, optionally substituted by one or more heteroatom-containing groups, and wherein X is an ether or ester bond connecting R4 to the starch.

22. The water-soluble film according to claim 21, wherein R1, R2, and R3 are the same C1 - C4 alkyl groups, and R4 is a C1 - C6 hydroxyalkylene group.

23. The water-soluble film according to claim 21, wherein R4 is a C3 - C6 hydroxyalkylene group.

24. The water-soluble film according to claim 21, wherein R1, R2, and R3 are each methyl, and R4 is a C3 - C6 hydroxyalkylene group.

25. The water-soluble film according to claim 21, wherein the cationic quaternary ammonium group is a quaternary 2-hydroxy-3-(trimethylammonium)propyl, 2-diethylaminoethyl, or 2,3-epoxypropyltrimethylammonium group or a combination thereof.

26. The water-soluble film according to claim 21, wherein the starch modified with cationic groups comprises starch modified with cationic trimethylammonium groups.

27. The water-soluble film according to claim 21, wherein the starch modified with cationic groups comprises starch modified with: 2-diethylaminoethyl salts, 2,3-epoxypropyltrimethylammonium salts, or 2-hydroxy-3-(trimethylammonium)propyl salts or a combination thereof.

28. The water-soluble film according to claim 27, wherein the 2-diethylaminoethyl salt comprises 2-diethylaminoethyl halide, the 2,3-epoxypropyltrimethylammonium salt comprises 2,3-epoxypropyltrimethylammonium halide, and the 2-hydroxy-3-(trimethylammonium)propyl salt comprises 2-hydroxy-3-(trimethylammonium)propyl halide.

29. The water-soluble film according to claim 27, wherein the 2-diethylaminoethyl salt comprises 2-diethylaminoethyl chloride, the 2,3-epoxypropyltrimethylammonium salt comprises 2,3-epoxypropyltrimethylammonium chloride, and the 2-hydroxy-3-(trimethylammonium)propyl salt comprises 2-hydroxy-3-(trimethylammonium)propyl chloride.

30. The water-soluble film according to claim 19, wherein the water-soluble starch further comprises unmodified starch and / or starch modified with non-ionic groups, and the modification level is in the range of about 0.1 - 10 mol% or about 1 - 5 mol%.

31. The water-soluble film according to claim 1, wherein the water-soluble polyvinyl alcohol comprises unmodified polyvinyl alcohol, polyvinyl alcohol modified with anionic groups, polyvinyl alcohol modified with cationic groups, or a combination thereof.

32. The water-soluble film according to claim 1, wherein the polyvinyl alcohol comprises polyvinyl alcohol modified with anionic groups, and the degree of modification is in the range of about 0.1 - 10 mol%.

33. The water-soluble film according to claim 32, wherein the degree of modification of the polyvinyl alcohol modified with anionic groups is in the range of about 1.0 - 5.0 mol%.

34. The water-soluble film according to claim 33, wherein the polyvinyl alcohol modified with anionic groups comprises polyvinyl alcohol modified with: itaconic acid, monomethyl maleate (MMM), methyl acrylate (MA), aminopropyl sulfonate, maleic acid, maleic anhydride, N-vinylpyrrolidone, N-vinylcaprolactam, derivatives of any of the foregoing, or a combination thereof.

35. The water-soluble film according to claim 34, wherein the polyvinyl alcohol modified with anionic groups comprises the polyvinyl alcohol modified with: monomethyl maleate, methyl acrylate, or a combination thereof.

36. The water-soluble film according to claim 1, which further comprises a plasticizer, and the plasticizer is present in a range of about 5.0 - 40.0 wt% based on the weight of the water-soluble film.

37. The water-soluble film according to claim 36, wherein the plasticizer comprises sorbitol, glycerine, glycerol, diglycerol, propylene glycol, dipropylene glycol, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol with a maximum MW of 400, 2-methyl-1,3-propanediol, ethanolamine, trimethylolpropane (TMP), polyether polyol, isomaltulose, maltitol, xylitol, erythritol, adonitol, galactitol, pentaerythritol, mannitol, sugar alcohol, or a combination thereof.

38. The water-soluble film according to claim 36, wherein the plasticizer comprises a bio-based plasticizer.

39. The water-soluble film according to claim 38, wherein the bio-based plasticizer comprises glycerol and / or sorbitol.

40. The water-soluble film according to claim 1, which further comprises a surfactant.

41. The water-soluble film according to claim 40, wherein the surfactant comprises a linear aliphatic ethoxylated surfactant.

42. The water-soluble film according to claim 41, wherein the linear aliphatic ethoxylated surfactant comprises lauryl polyether-6 formate, C9-C 15 ethylene oxide or a combination thereof.

43. The water-soluble film according to claim 1, which further comprises one or more of the following: defoamer, antioxidant, disinfectant, anti-adhesion agent, filler, sodium metabisulfite, sodium hydroxide, matting agent, slip agent, dispersant, or a combination thereof.

44. The water-soluble film according to claim 1, wherein according to MSTM-205, at a temperature in the range of 5 - 95 °C, the dissolution time of the water-soluble film in water is in the range of 30 - 300 seconds.

45. The water-soluble film according to claim 44, wherein at a temperature of about 10 °C and about 5 °C, the dissolution time is in the range of 30 - 300 seconds.

46. The water-soluble film according to claim 1, wherein the maximum stress of the water-soluble film is at least about 10 MPa.

47. The water-soluble film according to claim 1, wherein the elongation at break of the water-soluble film is at least about 150%.

48. The water-soluble film according to claim 1, wherein the weight ratio of the polyvinyl alcohol to the water-soluble starch is in the range of about 10:1 to about 1:

8.

49. The water-soluble film according to claim 48, wherein the weight ratio of the polyvinyl alcohol to the water-soluble starch is in the range of about 9:1 to about 1:

7.

50. The water-soluble film according to claim 49, wherein the weight ratio of the polyvinyl alcohol to the water-soluble starch is in the range of about 5:1 to about 1:6, or about 4:1 to 1:2 or about 4:1 to about 1:

1.

51. The water-soluble film according to claim 1, wherein the degree of hydrolysis of the polyvinyl alcohol is in the range of about 74 mol.% to about 99 mol.%.

52. The water-soluble film according to claim 51, wherein the degree of hydrolysis of the polyvinyl alcohol is in the range of about 74 mol.% to about 91 mol.%.

53. A water-soluble film comprising: Polyvinyl alcohol (PVOH) modified with a water-soluble anionic group, the degree of modification being in the range of about 1-5 mol.%; and Starch modified with a water-soluble cationic group, the degree of modification being in the range of about 0.05-5 mol.%, and the Brookfield viscosity of a 5 wt.% aqueous solution at 20 rpm and 87.8 °C being in the range of about 1-200 cP, wherein the gelatinization % of the cationic group-modified starch is at least about 5 wt.%, wherein the cationic group-modified starch is present in an amount in the range of about 20-60 wt.% based on the weight of the water-soluble film, and wherein the anionic group-modified PVOH and the cationic group-modified starch are miscible in the water-soluble film or the phase domains are less than 2000 μm.

54. An aqueous solution for forming the water-soluble film according to claim 1, the aqueous solution comprising: Water-soluble polyvinyl alcohol (PVOH); Water-soluble starch; and Water, wherein the gelatinization % of the water-soluble starch is at least about 5 wt.%, wherein the total solid content of the aqueous solution is at least 15 wt.% based on the weight of the aqueous solution, wherein the water-soluble starch is present in an amount in the range of about 5-65 wt.% based on the weight of the total solid content, and wherein the water-soluble polyvinyl alcohol (PVOH) and the water-soluble starch are miscible or have no bulk phase separation in the aqueous solution for at least 24 hours by visual inspection at a temperature in the range of about 20-100 °C.

55. The aqueous solution according to claim 54, wherein the water-soluble polyvinyl alcohol (PVOH) is soluble in water at a temperature of about 60°C or lower within about 60 minutes, or is soluble in water at a temperature of about 60°C within about 60 minutes, is soluble in water at a temperature of about 40°C within about 60 minutes, is soluble in water at a temperature of about 20°C within about 60 minutes, or is soluble in water at a temperature of about 10°C within about 60 minutes.

56. The aqueous solution according to claim 55, wherein the water-soluble polyvinyl alcohol (PVOH) is soluble in water at a temperature of about 40°C or lower within about 10 minutes.

57. The aqueous solution according to claim 54, wherein the renewable carbon index (RCI) of the total solid content is at least about 50%.

58. The aqueous solution according to claim 54, wherein the water-soluble starch comprises substantially gelatinized starch.

59. The aqueous solution according to claim 54, wherein the gelatinization percentage of the water-soluble starch is at least about 10 wt.%.

60. The aqueous solution according to claim 54, wherein the gelatinization percentage of the water-soluble starch is at least about 15 wt.%.

61. The aqueous solution according to claim 54, wherein the average molecular weight of the water-soluble starch is about 10 3 -10 7 g / mol or about 10 3 -10 6 g / mol.

62. The aqueous solution according to claim 61, wherein the average molecular weight of the water-soluble starch is in the range of about 10 4 -10 5 g / mol.

63. The aqueous solution according to claim 54, wherein the amylose content comprised in the water-soluble starch is in the range of 0 - 50 wt.% of the water-soluble starch.

64. The aqueous solution according to claim 63, wherein the amylose content comprised in the water-soluble starch is in the range of 0 - 30 wt.% of the water-soluble starch.

65. The aqueous solution according to claim 54, wherein the Brookfield viscosity of a 5 wt.% aqueous solution of the water-soluble starch at about 20 rpm and about 87.8°C is in the range of about 1 - 2000 cP.

66. The aqueous solution according to claim 54, wherein the Brookfield viscosity of a 5 wt.% aqueous solution of the water-soluble starch at about 20 rpm and about 87.8°C is in the range of about 2 - 100 cP.

67. The aqueous solution according to claim 54, wherein the total solid content of the aqueous solution is at least 25 wt.% by weight of the aqueous solution.

68. The aqueous solution according to claim 54, wherein the total solid content of the aqueous solution is at least 32 wt.% by weight of the aqueous solution.

69. The aqueous solution according to claim 54, wherein the total solid content of the aqueous solution is in the range of about 25 - 40 wt.% by weight of the aqueous solution.

70. The aqueous solution according to claim 54, wherein the water-soluble starch is present in an amount in the range of about 15 - 65 wt.% by weight of the total solid content.

71. The aqueous solution according to claim 70, wherein the water-soluble starch is present in an amount in the range of about 25 - 60 wt.% by weight of the total solid content.

72. The aqueous solution according to claim 54, wherein the water-soluble starch comprises unmodified starch, starch modified with non-ionic groups, starch modified with anionic groups, starch modified with cationic groups, or a combination thereof.

73. The aqueous solution according to claim 54, wherein the water-soluble starch comprises a starch modified with a cationic group, and the degree of modification is in the range of about 0.01 - 10 mol%.

74. The aqueous solution according to claim 54, wherein the water-soluble starch comprises a starch modified with a cationic group, and the degree of modification is in the range of about 0.1 - 1 mol%.

75. The aqueous solution according to claim 54, wherein the cationic group-modified starch comprises a cationic quaternary ammonium group-modified starch having the structure of formula A, wherein R1, R2 and R3 are each independently H or C1-C 10 alkyl or C1-C 10 hydroxyalkyl, wherein R4 is a straight-chain or branched C1-C 10 alkylene or C1-C 10 hydroxyalkylene, optionally substituted by one or more heteroatom-containing groups, and wherein X is an ether or ester bond connecting R4 to the starch.

76. The aqueous solution according to claim 75, wherein R1, R2, and R3 are the same C1-C4 alkyl groups, and R4 is a C1-C6 hydroxyalkylene group.

77. The aqueous solution according to claim 75, wherein R4 is a C3-C6 hydroxyalkylene group.

78. The aqueous solution according to claim 75, wherein R1, R2, and R3 are each methyl, and R4 is a C3-C6 hydroxyalkylene group.

79. The aqueous solution according to claim 75, wherein the cationic quaternary amine group is a quaternary 2-hydroxy-3-(trimethylammonium)propyl, 2-diethylaminoethyl, 2,3-epoxypropyltrimethylammonium group, or a combination thereof.

80. The aqueous solution according to claim 75, wherein the starch modified with a cationic group comprises a starch modified with a cationic trimethylammonium group.

81. The aqueous solution according to claim 75, wherein the starch modified with a cationic group comprises a starch modified with: 2-diethylaminoethyl salt, 2,3-epoxypropyltrimethylammonium salt, or 2-hydroxy-3-(trimethylammonium)propyl salt, or a combination thereof.

82. The aqueous solution according to claim 81, wherein the 2-diethylaminoethyl salt comprises 2-diethylaminoethyl halide, the 2,3-epoxypropyltrimethylammonium salt comprises 2,3-epoxypropyltrimethylammonium halide, and the 2-hydroxy-3-(trimethylammonium)propyl salt comprises 2-hydroxy-3-(trimethylammonium)propyl halide.

83. The aqueous solution according to claim 81, wherein the 2-diethylaminoethyl salt comprises 2-diethylaminoethyl chloride, the 2,3-epoxypropyltrimethylammonium salt comprises 2,3-epoxypropyltrimethylammonium chloride, and the 2-hydroxy-3-(trimethylammonium)propyl salt comprises 2-hydroxy-3-(trimethylammonium)propyl chloride.

84. The aqueous solution according to claim 73, wherein the water-soluble starch comprises a combination of the starch modified with a cationic group and unmodified starch.

85. The aqueous solution according to claim 54, wherein the polyvinyl alcohol (PVOH) comprises unmodified polyvinyl alcohol, polyvinyl alcohol modified with an anionic group, polyvinyl alcohol modified with a cationic group, or a combination thereof.

86. The aqueous solution according to claim 85, wherein the polyvinyl alcohol comprises the polyvinyl alcohol modified with an anionic group, and the degree of modification is in the range of about 0.1 - 10 mol%.

87. The aqueous solution according to claim 85, wherein the polyvinyl alcohol comprises the polyvinyl alcohol modified with an anionic group, and the degree of modification is in the range of about 1 - 5 mol%.

88. The aqueous solution according to claim 87, wherein the anion group-modified polyvinyl alcohol comprises polyvinyl alcohol modified with itaconic acid, monomethyl maleate (MMM), methyl acrylate (MA), aminopropyl sulfonate, maleic acid, maleic anhydride, N-vinylpyrrolidone, N-vinylcaprolactam, derivatives of any of the foregoing, or combinations thereof.

89. The aqueous solution according to claim 87, wherein the anion group-modified polyvinyl alcohol comprises the polyvinyl alcohol modified with monomethyl maleate, methyl acrylate, or combinations thereof.

90. The aqueous solution according to claim 54, further comprising a plasticizer, which is present in a range of about 5 - 40 wt.% based on the weight of the total solids content.

91. The aqueous solution according to claim 90, wherein the plasticizer comprises sorbitol, glycerine, glycerol, diglycerol, propylene glycol, dipropylene glycol, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol with a molecular weight of at most 400, 2-methyl-1,3-propanediol, ethanolamine, trimethylolpropane (TMP), polyether polyol, isomaltitol, maltitol, xylitol, erythritol, adonitol, galactitol, pentaerythritol, mannitol, sugar alcohols, or combinations thereof.

92. The aqueous solution according to claim 90, wherein the plasticizer comprises a bio-based plasticizer.

93. The aqueous solution according to claim 92, wherein the bio-based plasticizer comprises glycerol and / or sorbitol.

94. The aqueous solution according to claim 90, wherein the plasticizer does not include trimethylolpropane (TMP).

95. The aqueous solution according to claim 54, further comprising a surfactant.

96. The aqueous solution according to claim 95, wherein the surfactant comprises a linear aliphatic ethoxylated surfactant.

97. The aqueous solution according to claim 96, wherein the linear aliphatic ethoxylated surfactant comprises laureth-6 formate, C9-C 15 ethylene oxide, or a combination thereof.

98. The aqueous solution according to claim 54, further comprising at least one of the following: defoamer, antioxidant, disinfectant, anti-blocking agent, filler, sodium metabisulfite, sodium hydroxide, matting agent, slip agent, dispersant, or combinations thereof.

99. The aqueous solution according to claim 54, wherein the total solids content is in the range of about 28 - 35 wt.% based on the weight of the aqueous solution.

100. The aqueous solution according to claim 54, wherein the weight ratio of the polyvinyl alcohol to the water-soluble starch is in the range of about 10:1 to about 1:

8.

101. The aqueous solution according to claim 100, wherein the weight ratio of the polyvinyl alcohol to the water-soluble starch is in the range of about 6:1 to about 1:

6.

102. A method of forming the water-soluble film according to claim 1, the method comprising: casting the aqueous solution according to claim 54 onto a substrate with a specified thickness; and drying the water in the cast aqueous solution to form the water-soluble film.

103. An article, comprising: a sachet made of the water-soluble film according to claim 1, the sachet defining an internal sachet volume.

104. The article according to claim 103, further comprising the chemical composition contained in the internal sachet volume.

105. The article according to claim 104, wherein the chemical composition is a household care composition.

106. The article according to claim 105, wherein the household care composition is a liquid laundry detergent or a dishwashing detergent.

107. The article according to claim 103, wherein the compression strength of the sachet is at least about 300 N.

108. The article according to claim 107, wherein the compression strength of the sachet is at least about 600 N.

109. The article according to claim 103, wherein the sachet has a matte-to-matte type of seal.

110. The article according to claim 103, wherein according to MSTM-126, after mixing in water at a temperature of about 15 °C, the release time of the sachet does not exceed 300 seconds.

111. The article according to claim 110, wherein after mixing in water at about room temperature, the release time is in the range of 30 - 150 seconds.

112. The water-soluble film according to claim 17, wherein the non-ionic group-modified starch is a hydroxyethyl-modified starch.

113. The water-soluble film according to claim 112, wherein the hydroxyethyl-modified starch is present in the film in an amount in the range of about 10 PHR to about 80 PHR or about 10 PHR to about 40 PHR.

114. The water-soluble film according to claim 113, wherein When measured according to the fracture strain test, the fracture strain is greater than 300%.

115. The water-soluble film according to claim 1, wherein the water-soluble polyvinyl alcohol comprises bio-based polyvinyl alcohol.

116. The water-soluble film according to claim 115, wherein the ratio of the amount (by weight) of bio-based polyvinyl alcohol to non-bio-based polyvinyl alcohol is in the range of about 99:1 to about 1:99, or about 95:5 to about 5:99, or about 80:20 to about 20:80, or about 70:30 to about 30:70 or about 60:40 to about 40:60.

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