Cosmetic composition containing biodegradable cellulose ester microparticles

Abstract

A cosmetic composition comprising biodegradable microparticles formed from a biodegradable mixed cellulose ester is provided. More specifically, provided are cosmetic compositions containing environmentally friendly cellulose-based microparticles that can be used in a wide variety of cosmetic and personal care applications and provide enhanced cosmetic properties.

Description

BACKGROUND

[0001] Microparticles are particles having a diameter of less than 1 millimeter (mm). These particles are sometimes included in consumer products, such as personal care products and cosmetics. Many of these microparticle-containing products are designed to be applied and then washed or rinsed off the user’s body. When the microparticle-containing products are washed or rinsed off the user’s body, the particles are flushed into the sewer and received at municipal water treatment facilities. In the past, many known microparticles have been formed from plastic or polymeric materials, such as polyethylene, polypropylene, polymethyl methacrylate, nylon, polyurethane, and the like. These materials generally have limited biodegradability. Moreover, the small size of the particles limits their ability to be captured at water treatment facilities, such that the particles can be discharged from the facilities and into larger bodies of water (e.g., rivers, seas, and oceans). Once in these larger bodies of water, the plastic or polymeric microparticles can be ingested by wildlife or cause other environmental problems. Thus, there is a recent interest in exploring the possibility of producing microparticle particles from more environmentally friendly materials. However, consumers often have high expectations for personal care products and / or cosmetics, including those containing microparticles, that they use.

[0002] Accordingly, it would be desirable to develop commercially desirable cosmetic compositions containing biodegradable microparticles that meet the high expectations of the everyday consumer. SUMMARY

[0003] In one aspect, the present technology relates to a cosmetic composition comprising biodegradable microparticles, wherein the biodegradable microparticles comprise a mixed cellulose ester. The biodegradable microparticles further exhibit at least 50% biodegradability at 60 days according to at least one of the OECD 301B, OECD 301C, or OECD 301F test methods. Moreover, the mixed cellulose ester comprises: (a) an average degree of substitution of acetyl substituents (“DS Ac ”) in the range of 0.1 to 2.3, (b) an average degree of substitution of propionyl substituents (“DS Pr ”) or butyryl substituents (“DS Bu ”) in the range of 0.1 to 1.5, and (c) an average degree of substitution of hydroxyl substituents (“DS OH ”) in the range of 0.6 to 2.8.

[0004] In one aspect, the technology relates to a cosmetic composition comprising 0.5% to 15% by weight of biodegradable microparticles, wherein the biodegradable microparticles comprise a mixture of cellulose esters. In an embodiment, the biodegradable microparticles also exhibit at least 50% biodegradability at 60 days according to at least one of the OECD 301B, OECD 301C, or OECD 301F test methods, and have a biodegradability of 0.1 to 100 or 1 to 20 mg / L. 2 The average BET surface area is in the range of / g. Furthermore, in the embodiments, the mixed cellulose ester comprises: (a) an average degree of substitution (“DS”) of acetyl substituents in the range of 0.1 to 2.3 or 1.5 to 2.3. Ac (b) The average degree of substitution of butyryl substituents in the range of 0.1 to 1.5 or 0.1 to 0.3 (“DS”). Bu (c) the average degree of substitution of hydroxyl substituents in the range of 0.6 to 2.8 or 0.6 to 1.0 (“DS”). OH ”).

[0005] In one aspect, the present technology relates to a method for forming a cosmetic composition comprising biodegradable microparticles. Typically, the method includes: (a) providing a plurality of biodegradable microparticles comprising a mixed cellulose ester, wherein the biodegradable microparticles exhibit at least 50% biodegradability at 60 days according to at least one of OECD 301B, OECD 301C, or OECD 301F test methods; (b) combining the biodegradable microparticles with one or more cosmetic additives to form a pre-cosmetic mixture; and (c) forming a cosmetic composition from the pre-cosmetic mixture. Furthermore, the mixed cellulose ester comprises: (a) an average degree of substitution (“DS”) of acetyl substituents in the range of 0.1 to 2.3. Ac (b) Average degree of substitution of propionyl substituents in the range of 0.1 to 1.5 (“DS”) Pr ") or the average degree of substitution of butyryl substituents ("DS") Bu (c) the average degree of substitution of hydroxyl substituents in the range of 0.6 to 2.8 (“DS”). OH ”). Attached Figure Description

[0006] Figure 1 This is a schematic diagram of an example method for manufacturing cellulose ester microparticles.

[0007] Figure 2 This is a more detailed schematic diagram of an example method for manufacturing cellulose ester microparticles.

[0008] Figure 3is a schematic of an alternative method for making cellulose ester microparticles by continuous particle formation.

[0009] Figure 4 is a schematic of an alternative method for making cellulose ester microparticles by emulsion / dispersion formation and particle hardening of separate coating and aqueous mixtures.

[0010] Figure 5 is a schematic of an alternative method for making cellulose ester microparticles by combined emulsion / dispersion formation.

[0011] Figure 6 is a schematic of an alternative method for making cellulose ester microparticles by combined emulsion / dispersion formation and particle hardening.

[0012] Figure 7 is a schematic of an alternative method for making cellulose ester microparticles by solvent flashing prior to particle hardening. DETAILED DESCRIPTION

[0013] The present disclosure relates to cosmetic compositions formed from biodegradable cellulose ester microparticles that exhibit superior properties relative to conventional microparticles. The methods disclosed herein enable control of the robustness of the microparticles produced, such that microparticles with desired properties can be obtained. Alternatively, microparticles produced from bulk cellulose ester (produced) by mechanical micronization or size reduction can also provide the desired properties for CE microparticles. These qualities, along with the biodegradability of the CE, make the CE microparticles produced herein highly suitable for use in cosmetic compositions.

[0014] The application can be more easily understood by reference to the following detailed description and examples provided herein. It is to be understood that the present disclosure is not limited to the specific methods, formulations, and conditions described, as such can vary. It is also to be understood that the terminology used herein is for the purpose of describing particular aspects of the disclosed embodiments and is not intended to be limiting.

[0015] Values can be expressed as "about" or "approximately" a given value. Similarly, ranges can be expressed herein as from "about" one particular value and / or to "about" another particular value. When such ranges are expressed, another aspect includes from the one particular value and / or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent "about," it will be understood that the particular value forms another aspect.

[0016] As used herein, the terms "one," "a," and "the" mean one or more.

[0017] As used herein, the term "and / or," when used in a list of two or more items, means that any one of the listed items can be employed by itself, or any combination of two or more of the listed items can be employed. For example, if a composition is described as containing components A, B, and / or C, the composition can contain A alone; B alone; C alone; A and B in combination; A and C in combination; B and C in combination; or A, B, and C in combination.

[0018] As used herein, the terms "comprising," "comprises" and "comprise" are open-ended transitional phrases used to transition from a preceding clause to one or more elements that the clause describes, wherein the one or more elements listed after the transitional phrase are not necessarily the only elements that make up the subject of the clause.

[0019] As used herein, the terms "having," "has," and "have" have the same open-ended meaning as "comprising," "comprises," and "comprise" provided above.

[0020] As used herein, the terms "including," "include," and "included" have the same open-ended meaning as "comprising," "comprises," and "comprise" provided above.

[0021] As used herein, "mixed cellulose ester" shall mean a cellulose ester having at least two different ester substituents on a single cellulose ester polymer chain.

[0022] "Degree of substitution" is used to describe the average level of substitution of substituents per anhydroglucose unit ("AGU"). Generally, conventional cellulose contains three hydroxyl groups that can be substituted per AGU unit. Thus, the DS can have a value between 0 and 3. However, a low molecular weight cellulose mixed ester can have a total degree of substitution slightly higher than 3 resulting from end group contributions. Low molecular weight cellulose mixed esters are discussed in more detail later in the present disclosure. Since the DS is a statistical average, a value of 1 does not guarantee that every AGU has one substituent. In some cases, there can be unsubstituted anhydroglucose units, some with two substituents and some with three substituents, and typically the value will be a non-integer. "Total DS" is defined as the average number of all substituents per anhydroglucose unit. The degree of substitution can also refer to a specific substituent per AGU, such as, for example, a hydroxyl group, an acetyl group, a butanoyl group, or a propionyl group. Further, the degree of substitution can specify a particular hydroxyl group based on the carbon units of the anhydroglucose unit.

[0023] When the degree of substitution refers to hydroxyl groups, i.e., DS OH OH

[0024] This specification uses numerical ranges to quantify certain parameters related to the present application. It should be understood that when numerical ranges are provided, these ranges are to be construed as providing literal support for every number within the range. For example, a range provided of 10 to 100 should be construed as providing literal support for a claim reciting 10, a claim reciting 100, and claims reciting any number between 10 and 100, e.g., 73.5.

[0025] This specification uses specific numerical values to quantify certain parameters related to the present application, where the specific numerical values do not explicitly belong to a part of a numerical range. It should be understood that each specific numerical value provided herein should be read as providing literal support for a broad, intermediate, and narrow range. The broad range associated with each specific numerical value is the numerical value (rounded to two significant figures) plus or minus 60% of the numerical value. The intermediate range associated with each specific numerical value is the numerical value (rounded to two significant figures) plus or minus 30% of the numerical value. The narrow range associated with each specific numerical value is the numerical value (rounded to two significant figures) plus or minus 15% of the numerical value. For example, if the specification describes a specific temperature of 62 °F, such description provides literal support for a broad numerical range of 25 °F to 99 °F (62 °F + / - 37 °F), an intermediate numerical range of 43 °F to 81 °F (62 °F + / - 19 °F), and a narrow numerical range of 53 °F to 71 °F (62 °F + / - 9 °F). These broad, intermediate, and narrow numerical ranges apply not only to specific values, but also to differences between such specific values. Thus, if the specification describes a first pressure of 110 psia and a second pressure of 48 psia (a difference of 62 psi), the broad, intermediate, and narrow ranges for the pressure difference between these two streams would be 25 to 99 psi, 43 to 81 psi, and 53 to 71 psi, respectively.

[0026] Throughout this application, where publications are referenced, the disclosures of these publications in their entireties are hereby incorporated by reference into this application, to the extent that the referenced publications are not inconsistent with the present application, so as to more fully describe the state of the art to which the present application pertains.

[0027] In certain aspects, the CE microparticles can be produced via a solvent or emulsion method. Reference is now made to Figure 1 ​​The cellulose ester (CE) 100, solvent 102, water 104, hydrocolloid 106, and surfactant 108 can be combined in one or more units to make the CE microparticles 112. In the illustrated example, the CE 100, solvent 102, water 104, hydrocolloid 106, and surfactant 108 are combined at unit 110 to form an initial emulsion therein. The initial emulsion includes a dispersed phase and a continuous phase. The dispersed phase includes at least a portion of the CE 100 and at least a portion of the solvent 102. The continuous phase includes at least a portion of the water 104, at least a portion of the hydrocolloid 106, and at least a portion of the surfactant 108.

[0028] Once the initial emulsion is combined, the initial emulsion can be agitated at unit 110 to form a pre-hardened dispersion including a solid phase and a liquid phase. The solid phase includes initial microparticles including at least a portion of the CE 100 and at least a portion of the solvent 102. The liquid phase includes at least a portion of the water 104, at least a portion of the hydrocolloid 106, and at least a portion of the surfactant 108. Additional water 104 (i.e., drowning liquid / extractant) can be added to the pre-hardened dispersion to increase the water concentration around the initial microparticles. An initial hardened dispersion including the initial microparticles and the drowning liquid is thereby formed. The initial hardened dispersion can be agitated at unit 110 to facilitate solvent transfer from the initial microparticles to the drowning liquid. This solvent transfer facilitates hardening of the initial microparticles, resulting in hardened CE microparticles 112 that are entrained in the solvent-laden drowning liquid.

[0029] The CE microparticles 112 can be recovered from this dispersion 114 initially by processing at a solid / liquid separation unit 116. A solid stream 118 including the CE microparticles 112 can be directed to a solid processing unit 120 where the CE microparticles 112 are washed with water 122 and then dried to recover the CE microparticles 112, as will be described in greater detail below. A liquid stream 124 formed from the solvent-laden drowning liquid can be directed to a liquid processing unit 126. Optionally, an excess liquid stream 128 directed from unit 110 and a wash water stream 130 from unit 120 can also be received at unit 126 for processing therein.

[0030] At unit 126, the liquid received therein can be separated into at least a water-rich stream 132 and a solvent-rich stream 134. In some embodiments, the water-rich stream 132 can be recovered and used, for example, at least in part, in unit 110. Further, the solvent-rich stream 134 can be recycled and used as at least a portion of the solvent used in unit 110 to form the CE microparticles 112. The recovery of water and / or the reuse of solvent facilitates improved economics of the CE microparticle formation process described herein.

[0031] In certain aspects, the CE microparticles can be produced from a mixed cellulose ester (e.g., cellulose acetate butyrate CAB) by subjecting a bulk cellulose ester (CE) form to a mechanical micronization or size reduction process. In embodiments, the mechanical micronization or size reduction process is a comminution process that uses one or more high velocity gas or liquid jets to comminute and reduce the size of the bulk CE material. In embodiments, the comminution process is a jet milling process that uses one or more high velocity gas jets (e.g., air or inert gas) to reduce the size of the bulk CE material. In embodiments, the jet milling process utilizes a fluid bed opposed jet mill. In embodiments, the mechanical size reduction process provides CE microparticles having an average sphericity of less than 60%, or less than 50%, or less than 40%, or less than 30%. In embodiments, the mechanical size reduction process provides CE microparticles having a D[4,3] average particle size of less than 40, or less than 30, or less than 20 microns.

[0032] mixed cellulose ester

[0033] In one embodiment or in combination with any of the embodiments mentioned herein, the CE 100 can be a mixed cellulose ester.

[0034] Generally, the cellulose esters described herein, such as the CE 100, can be produced by any method known in the art. Examples of methods for producing cellulose esters are taught in Kirk-Othmer, Encyclopedia of Chemical Technology, 5thEdition, Volume 5, Wiley-Interscience, New York (2004), pages 394-444, the disclosure of which is incorporated by reference in its entirety into the present specification. Cellulose is the starting material for producing cellulose esters, which can be obtained in different grades and from sources such as, for example, lignocellulosic sources (e.g., softwood pulp, hardwood pulp), cotton linters, corn fiber and other agricultural sources, and sources of bacterial cellulose.

[0035] One method of producing cellulose esters is by esterification. In this method, cellulose is mixed with an appropriate organic acid, acid anhydride, and / or catalyst, and then converted to a cellulose triester. Ester hydrolysis is then performed by adding a water-acid mixture to the cellulose triester, which can then be filtered to remove any gelled particles or fibers. Water is added to the mixture to precipitate the cellulose ester. The cellulose ester can then be washed with water to remove reaction byproducts, followed by dewatering and drying.

[0036] Suitable acylating agents for use herein can include, but are not limited to, alkyl or aryl carboxylic acid anhydides, carboxylic acid halides, and / or carboxylic acid esters containing the above-described alkyl or aryl groups suitable for the acyl substituents of the substituted cellulose esters described herein. Examples of suitable carboxylic acid anhydides include, but are not limited to, acetic anhydride, propionic anhydride, butyric anhydride, pivalic anhydride, benzoic anhydride, and naphthoic anhydride. Examples of carboxylic acid halides include, but are not limited to, acetyl, propionyl, butyryl, pivaloyl, benzoyl, and naphthoyl chloride or bromide. Examples of carboxylic acid esters include, but are not limited to, acetyl, propionyl, butyryl, pivaloyl, benzoyl, and naphthoyl methyl ester. In one or more embodiments, the acylating agent can be one or more carboxylic acid anhydides selected from the group consisting of acetic anhydride, propionic anhydride, butyric anhydride, pivalic anhydride, benzoic anhydride, and naphthoic anhydride.

[0037] In various embodiments, the cellulose triester that is hydrolyzed can have three substituents independently selected from alkylacyl groups having from 2 to 12 carbon atoms. Examples of cellulose triesters include cellulose triacetate, cellulose tripropionate, cellulose tributyrate, or mixed triesters of cellulose such as cellulose acetate propionate and cellulose acetate butyrate. These cellulose triesters can be prepared by a number of methods known to those skilled in the art. For example, cellulose triesters can be prepared by heterogeneous acylation of cellulose in a mixture of carboxylic acids and anhydrides in the presence of a catalyst such as H2SO4 4) In various embodiments, the cellulose triester that is hydrolyzed can have three substituents independently selected from alkylacyl groups having from 2 to 12 carbon atoms. Examples of cellulose triesters include cellulose triacetate, cellulose tripropionate, cellulose tributyrate, or mixed triesters of cellulose such as cellulose acetate propionate and cellulose acetate butyrate. These cellulose triesters can be prepared by a number of methods known to those skilled in the art. For example, cellulose triesters can be prepared by heterogeneous acylation of cellulose in a mixture of carboxylic acids and anhydrides in the presence of a catalyst such as H2SO4

[0038] After esterification of the cellulose to a triester, a portion of the acyl substituents can be removed by hydrolysis or alcoholysis to give a secondary cellulose ester. Secondary cellulose esters can also be prepared directly without hydrolysis by using a limited amount of acylating agent. This method is particularly useful when the reaction is carried out in a solvent that dissolves the cellulose.

[0039] The cellulose esters thus prepared generally comprise the following structure:

[0040]

[0041] where R 2 , R 3 , and R 6 are hydrogen (provided that R 2 , R 3 , and R 6 cannot all be hydrogen), alkyl-acyl and / or aryl-acyl groups bound to the cellulose via ester linkages such as those described above.

[0042] The cellulose ester prepared by these methods can have a degree of polymerization ("DP") of at least 10. In other embodiments, the DP of the cellulose ester can be at least 50, at least 100, or at least 250. In other embodiments, the DP of the cellulose ester can be in the range of from about 5 to about 100, or in the range of from about 10 to about 50.

[0043] Suitable acylating agents for use herein can include, but are not limited to, alkyl or aryl carboxylic acid anhydides, carboxylic acid halides, and / or carboxylic acid esters containing the above-described alkyl or aryl groups suitable for acyl substitution of the substituted cellulose esters described herein. Examples of suitable carboxylic acid anhydides include, but are not limited to, acetic anhydride, propionic anhydride, butyric anhydride, pivalic anhydride, benzoic anhydride, and naphthoic anhydride. Examples of carboxylic acid halides include, but are not limited to, acetyl, propionyl, butyryl, pivaloyl, benzoyl, and naphthoyl chloride or bromide. Examples of carboxylic acid esters include, but are not limited to, acetyl, propionyl, butyryl, pivaloyl, benzoyl, and naphthoyl methyl ester. In one or more embodiments, the acylating agent can be one or more carboxylic acid anhydides selected from acetic anhydride, propionic anhydride, butyric anhydride, pivalic anhydride, benzoic anhydride, and naphthoic anhydride.

[0044] In a first aspect, the present application discloses a mixed ester cellulose ester ("MCE") comprising: (1) a plurality of acetyl substituents; (2) a plurality of propionyl substituents; and (3) a plurality of hydroxyl substituents, wherein: the MCE has an average degree of substitution ("DS Ac ") of the acetyl substituents of from 0.1 to 2.3, the MCE has an average degree of substitution ("DS Pr ") of the propionyl substituents of from 0.1 to 1.5, and the MCE has an average degree of substitution ("DS OH ") of the hydroxyl substituents of from 0.6 to 2.8.

[0045] In one embodiment or in combination with any other embodiment, class, or subclass of this first aspect, the DS Ac is at least 0.1, at least 0.2, at least 0.3, at least 0.4, at least 0.5, at least 0.6, at least 0.7, at least 0.8, at least 0.9, at least 1.0, at least 1.1, at least 1.2, at least 1.3, at least 1.4, at least 1.5, at least 1.6, at least 1.7, at least 1.8, at least 1.9, or at least 2.0. Additionally, or in the alternative, the DS Ac is less than 2.3, less than 2.2, less than 2.1, less than 2.0, less than 1.9, less than 1.8, less than 1.7, less than 1.6, less than 1.5, less than 1.4, less than 1.3, less than 1.2, less than 1.1, less than 1.0, less than 0.9, less than 0.8, less than 0.7, less than 0.5, less than 0.4, or less than 0.3.

[0046] In an embodiment, or in combination with any other embodiment, category or subcategory of this first aspect, wherein DS Ac is 0.6 to 2.2, or 0.6 to 2.1, or 0.6 to 2.0, or 0.6 to 1.9, or 0.6 to 1.8, or 0.7 to 2.3, or 0.7 to 2.2, or 0.7 to 2.1, or 0.7 to 2.0, or 0.7 to 1.9, or 0.8 to 2.3, or 0.8 to 2.2, or 0.8 to 2.1, or 0.8 to 2.0, or 0.8 to 1.9, or 0.9 to 2.3, or 0.9 to 2.2, or 0.9 to 2.1, or 0.9 to 2.0, or 0.9 to 1.9, or 1.0 to 2.3, or 1.0 to 2.2, or 1.0 to 2.1, or 1.0 to 2.0, or 1.0 to 1.9, or 1.1 to 2.3, or 1.1 to 2.2, or 1.1 to 2.1, or 1.1 to 2.0, or 1.1 to 1.9, or 1.2 to 2.3, or 1.2 to 2.2, or 1.2 to 2.1, or 1.2 to 2.0, or 1.2 to 1.9, or 0.6 to 1.5, or 0.6 to 1.3, or 0.6 to 1.1, or 0.6 to 0.9, or 0.7 to 1.5, or 0.7 to 1.3, or 0.7 to 1.1, or 0.7 to 0.9.

[0047] In an embodiment, or in combination with any other embodiment, category or subcategory of this first aspect, wherein DS Pr is at least 0.05, at least 0.1, at least 0.15, at least 0.2, at least 0.3, at least 0.4, at least 0.5, at least 0.6, at least 0.7, at least 0.8, at least 0.9, at least 1.0, at least 1.1, at least 1.2, at least 1.3, or at least 1.4. Additionally, or in the alternative, DS Pr is less than 1.5, less than 1.4, less than 1.3, less than 1.2, less than 1.1, less than 1.0, less than 0.9, less than 0.8, less than 0.7, less than 0.5, less than 0.4, less than 0.35, less than 0.3, or less than 0.25.

[0048] In an embodiment, or in combination with any other embodiment, category or subcategory of this first aspect, wherein DS Pr0.05 to 0.9, or 0.05 to 0.85, or 0.05 to 0.8, or 0.05 to 0.75, or 0.05 to 0.7, or 0.05 to 0.6, or 0.05 to 0.5, or 0.05 to 0.4, or 0.05 to 0.35, or 0.05 to 0.3, or 0.05 to 0.25, or 0.1 to 0.9, or 0.1 to 0.85, or 0.1 to 0.8, or 0.1 to 0.75, or 0.1 to 0.7, or 0.1 to 0.6, or 0.1 to 0.5, or 0.1 to 0.4, or 0.1 to 0.35, or 0.1 to 0.3, or 0.1 to 0.25, or 0.15 to 0.95, or 0.15 to 0.9, or 0.15 to 0.85, or 0.15 to 0.8, or 0.15 to 0.75, or 0.15 to 0.7, or 0.15 to 0.65, or 0.15 to 0.6, or 0.15 to 0.5, or 0.15 to 0.4, or 0.15 to 0.35, or 0.15 to 0.3, or 0.15 to 0.25, or 0.2 to 0.95, or 0.2 to 0.9, or 0.2 to 0.85, or 0.2 to 0.8, or 0.2 to 0.75, or 0.2 to 0.7, or 0.2 to 0.65, 0.25 to 0.95, or 0.25 to 0.9, or 0.25 to 0.85, or 0.25 to 0.8, or 0.25 to 0.75, or 0.25 to 0.7, or 0.25 to 0.65, or 0.3 to 0.95, or 0.3 to 0.9, or 0.3 to 0.85, or 0.3 to 0.8, or 0.3 to 0.75, or 0.3 to 0.7, or 0.3 to 0.65, or 0.35 to 0.95, or 0.35 to 0.9, or 0.35 to 0.85, or 0.35 to 0.8, or 0.35 to 0.75, or 0.35 to 0.7, or 0.35 to 0.65, or 0.4 to 0.95, or 0.4 to 0.9, or 0.4 to 0.85, or 0.4 to 0.8, or 0.4 to 0.75, or 0.4 to 0.7, or 0.4 to 0.65, or 0.45 to 0.95, or 0.45 to 0.9, or 0.45 to 0.85, or 0.45 to 0.8, or 0.45 to 0.75, or 0.45 to 0.7, or 0.45 to 0.65, or 0.5 to 0.95, or 0.5 to 0.9, or 0.5 to 0.85, or 0.5 to 0.8, or 0.5 to 0.75, or 0.5 to 0.7, or 0.5 to 0.65, or 0.1 to 0.9, or 0.1 to 0.85, or 0.1 to 0.8.

[0049] In one embodiment, or in combination with any other embodiment, category or subcategory of this first aspect, the DS is OHat least 0.5, at least 0.55, at least 0.6, at least 0.65, at least 0.7, at least 0.75, at least 0.8, at least 0.85, at least 0.9, at least 1.0, at least 1.1, at least 1.2, at least 1.3, at least 1.4, at least 1.5, at least 1.6, at least 1.7, at least 1.8, at least 1.9, at least 2.0, at least 2.1, at least 2.2, at least 2.3, at least 2.4, at least 2.5, or at least 2.6. Additionally, or in the alternative, DS OH less than 2.8, less than 2.7, less than 2.6, less than 2.5, less than 2.4, less than 2.3, less than 2.2, less than 2.1, less than 2.0, less than 1.9, less than 1.8, less than 1.7, less than 1.6, less than 1.5, less than 1.4, less than 1.3, less than 1.2, less than 1.15, less than 1.1, less than 1.05, less than 1.0, less than 0.95, less than 0.9, less than 0.85, or less than 0.8.

[0050] In an embodiment, or in combination with any other embodiment, class or subclass of this first aspect, wherein DS OH0.5 to 1.5, or 0.5 to 1.45, or 0.5 to 1.40, or 0.5 to 1.35, or 0.5 to 1.30, or 0.5 to 1.25, or 0.5 to 1.2, or 0.5 to 1.15, or 0.5 to 1.1, or 0.5 to 1.05, or 0.5 to 1.0, or 0.5 to 0.95, or 0.5 to 0.9, or 0.5 to 0.85, or 0.5 to 0.8, or 0.55 to 1.5, or 0.55 to 1.45, or 0.55 to 1.40, or 0.55 to 1.35, or 0.55 to 1.30, or 0.55 to 1.25, or 0.55 to 1.2, or 0.55 to 1.15, or 0.55 to 1.1, or 0.55 to 1.05, or 0.55 to 1.0, or 0.55 to 0.95, or 0.55 to 0.9, or 0.55 to 0.85, or 0.55 to 0.8, or 0.6 to 1.5, or 0.6 to 1.45, or 0.6 to 1.40, or 0.6 to 1.35, or 0.6 to 1.30, or 0.6 to 1.25, or 0.6 to 1.2, or 0.6 to 1.15, or 0.6 to 1.1, or 0.6 to 1.05, or 0.6 to 1.0, or 0.6 to 0.95, or 0.6 to 0.9, or 0.6 to 0.85, or 0.6 to 0.8, or 0.65 to 1.5, or 0.65 to 1.45, or 0.65 to 1.40, or 0.65 to 1.35, or 0.65 to 1.30, or 0.65 to 1.25, or 0.65 to 1.2, or 0.65 to 1.15, or 0.65 to 1.1, or 0.65 to 1.05, or 0.65 to 1.0, or 0.65 to 0.95, or 0.65 to 0.9, or 0.65 to 0.85, or 0.65 to 0.8, or 0.7 to 1.5, or 0.7 to 1.45, or 0.7 to 1.40, or 0.7 to 1.35, or 0.7 to 1.30, or 0.7 to 1.25, or 0.7 to 1.2, or 0.7 to 1.15, or 0.7 to 1.1, or 0.7 to 1.05, or 0.7 to 1.0, or 0.7 to 0.95, or 0.7 to 0.9, or 0.7 to 0.85, or 0.7 to 0.8, or 0.75 to 1.5, or 0.75 to 1.45, or 0.75 to 1.40, or 0.75 to 1.35, or 0.75 to 1.30, or 0.75 to 1.25, or 0.75 to 1.2, or 0.75 to 1.15, or 0.75 to 1.1, or 0.75 to 1.05, or 0.75 to 1.0, or 0.75 to 0.95, or 0.75 to 0.9, or 0.8 to 1.5, or 0.8 to 1.45, or 0.8 to 1.40, or 0.8 to 1.35, or 0.8 to 1.30, or 0.8 to 1.25, or 0.8 to 1.2, or 0.8 to 1.15, or 0.8 to 1.1, or 0.8 to 1.05, or 0.8 to 1.0, or 0.8 to 0.95, or 0.8 to 0.9, or 0.8 to 0.85, or 0.8 to 0.8, or 0.9 to 1.5, or 0.9 to 1.45, or 0.9 to 1.40, or 0.9 to 1.35, or 0.9 to 1.30, or 0.9 to 1.25, or 0.9 to 1.2, or 0.9 to 1.15, or 0.9 to 1.1, or 0.9 to 1.05, or 0.9 to 1.0, or 0.9 to 0.95, or 0.9 to 0.9, or 0.9 to 0.85, or 0.9 to 0.8, or 1.0 to 1.5, or 1.0 to 1.45, or 1.0 to 1.40, or 1.0 to 1.35, or 1.0 to 1.30, or 1.0 to 1.25, or 1.0 to 1.2, or 1.0 to 1.15, or 1.0 to 1.1, or 1.0 to 1.05, or 1.0 to 1.0, or 1.0 to 0.95, or 1.0 to 0.9, or 1.0 to 0.85, or 1.0 to 0.8, or 1.0 to 0.95, or 0.8 to 0.9, or 0.85 to 1.5, or 0.85 to 1.45, or 0.85 to 1.40, or 0.85 to 1.35, or 0.85 to 1.30, or 0.85 to 1.25, or 0.85 to 1.2, or 0.85 to 1.15, or 0.85 to 1.1, or 0.85 to 1.05, or 0.85 to 1.0, or 0.85 to 0.95, or 0.85 to 0.9.

[0051] In an embodiment, or in combination with any other embodiment, category or subcategory of this first aspect, wherein the DS Pr and the sum of DS Ac is 1.9 to 2.44, or 1.9 to 2.0, or 1.9 to 2.1, or 1.9 to 2.2, or 1.9 to 2.3, or 2.0 to 2.44, or 2.0 to 2.1, or 2.0 to 2.2, or 2.0 to 2.3, or 2.1 to 2.44, or 2.1 to 2.2, or 2.1 to 2.3, or 2.2 to 2.44, or 2.2 to 2.3.

[0052] In an embodiment, or in combination with any other embodiment, category or subcategory of this first aspect, wherein the mixed cellulose ester has a ratio of hydroxyl substituents to acetyl substituents of at least 0.4:1, at least 0.45:1, at least 0.5:1, at least 0.6:1, at least 0.7:1, at least 0.8:1, at least 0.9:1, at least 1:1, at least 1.1:1, at least 1.2:1, at least 1.3:1, at least 1.4:1, at least 1.5:1, at least 1.6:1, at least 1.7:1, at least 1.8:1, at least 1.9:2, or at least 2:1. Additionally, in the alternative, the mixed cellulose ester has a ratio of hydroxyl substituents to acetyl substituents of less than 2:1, less than 1.9:1, less than 1.8:1, less than 1.7:1, less than 1.6:1, less than 1.5:1, less than 1.4:1, less than 1.3:1, less than 1.2:1, less than 1.1:1, or less than 1:1.

[0053] In an embodiment or in combination with any other embodiment, class or subclass of this first aspect, wherein the ratio of hydroxyl substituents to propionyl substituents of the MCE is at least 0.4:1, at least 0.45:1, at least 0.5:1, at least 0.6:1, at least 0.7:1, at least 0.8:1, at least 0.9:1, at least 1:1, at least 1.1:1, at least 1.2:1, at least 1.3:1, at least 1.4:1, at least 1.5:1, at least 1.6:1, at least 1.7:1, at least 1.8:1, at least 1.9:2, or at least 2:1. Additionally or in the alternative, the ratio of hydroxyl substituents to propionyl substituents of the MCE is less than 2:1, less than 1.9:1, less than 1.8:1, less than 1.7:1, less than 1.6:1, less than 1.5:1, less than 1.4:1, less than 1.3:1, less than 1.2:1, less than 1.1:1, or less than 1:1; or less than 0.9:1; or less than 0.8:1; or less than 0.7:1; or less than 0.6:1; or less than 0.5:1.

[0054] In an embodiment or in combination with any other embodiment, class or subclass of this first aspect, wherein the MCE exhibits biodegradability of at least 40%, biodegradability of at least 45%, or biodegradability of at least 50%, or biodegradability of at least 55%, biodegradability of at least 60%, or biodegradability of at least 65%, or biodegradability of at least 70%, or biodegradability of at least 75%, or biodegradability of at least 80%, or biodegradability of at least 85% according to at least one of the OECD 301B, OECD 301C, or OECD 301F test methods at 56 days.

[0055] In an embodiment or in combination with any other embodiment, class or subclass of this first aspect, wherein the MCE exhibits biodegradability of at least 40%, biodegradability of at least 45%, or biodegradability of at least 50%, or biodegradability of at least 55%, biodegradability of at least 60%, or biodegradability of at least 65%, or biodegradability of at least 70%, or biodegradability of at least 75%, or biodegradability of at least 80%, or biodegradability of at least 85% according to at least one of the OECD 301B, OECD 301C, or OECD 301F test methods at 60 days.

[0056] In an embodiment or in combination with any other embodiment, class or subclass of this first aspect, the MCE has a weight average molecular weight in the range of 5,000 to 100,000 Da, or 5,000 to 50,000 Da, or 5,000 to 25,000 Da, or 15,000 to 100,000 Da, or 15,000 to 50,000 Da, or 15,000 to 25,000 Da, or 50,000 to 100,000 Da, or 75,000 to 100,000 Da, or 15,000 to 250,000 Da.

[0057] In a second aspect, the present application discloses a mixed cellulose ester (“MCE”) comprising: (1) a plurality of acetyl substituents; (2) a plurality of propionyl substituents; and (3) a plurality of hydroxyl substituents, wherein: the MCE has an average degree of substitution (“DS Ac ”) of the acetyl substituents of 0.1 to 2.3, or 0.1 to 1.9, or 1.5 to 2.3, the MCE has an average degree of substitution (“DS Pr ”) of the propionyl substituents of 0.1 to 1.5, or 0.1 to 0.6, or 0.1 to 0.3, and the MCE has an average degree of substitution (“DS OH ”) of the hydroxyl substituents of 0.7 to 2.8 or 0.7 to 1.2.

[0058] In an embodiment or in combination with any other embodiment, class or subclass of this second aspect, the DS Ac is at least 0.1, at least 0.2, at least 0.3, at least 0.4, at least 0.5, at least 0.6, at least 0.7, at least 0.8, at least 0.9, at least 1.0, at least 1.1, at least 1.2, at least 1.3, at least 1.4, at least 1.5, at least 1.6, at least 1.7, at least 1.8, at least 1.9, or at least 2.0. Additionally, or in the alternative, the DS Ac is less than 2.3, less than 2.2, less than 2.1, less than 2.0, less than 1.9, less than 1.8, less than 1.7, less than 1.6, less than 1.5, less than 1.4, less than 1.3, less than 1.2, less than 1.1, less than 1.0, less than 0.9, less than 0.8, less than 0.7, less than 0.5, less than 0.4, or less than 0.3.

[0059] In an embodiment or in combination with any other embodiment, class or subclass of this second aspect, the DS Ac0.6 to 0.7, or 0.6 to 0.8, or 0.6 to 0.9, or 0.6 to 1.0, or 0.6 to 1.1, or 0.6 to 1.2, or 0.6 to 1.3, or 0.6 to 1.4, or 0.6 to 1.5, or 0.6 to 1.6, or 0.6 to 1.7, or 0.6 to 1.8, or 0.6 to 1.9, or 0.6 to 2.0, or 0.6 to 2.1, or 0.7 to 0.9, or 0.7 to 1.0, or 0.7 to 1.1, or 0.7 to 1.2, or 0.7 to 1.3, or 0.7 to 1.4, or 0.7 to 1.5, or 0.7 to 1.6, or 0.7 to 1.7, or 0.7 to 1.8, or 0.7 to 1.9, or 0.7 to 2.0, or 0.7 to 2.1, or 0.8 to 0.9, or 0.8 to 1.0, or 0.8 to 1.1, or 0.8 to 1.2, or 0.8 to 1.3, or 0.8 to 1.4, or 0.8 to 1.5, or 0.8 to 1.6, or 0.8 to 1.7, or 0.8 to 1.8, or 0.8 to 1.9, or 0.8 to 2.0, or 0.8 to 2.1, or 0.9 to 1.0, or 0.9 to 1.1, or 0.9 to 1.2, or 0.9 to 1.3, or 0.9 to 1.4, or 0.9 to 1.5, or 0.9 to 1.6, or 0.9 to 1.7, or 0.9 to 1.8, or 0.9 to 1.9, or 0.9 to 2.0, or 0.9 to 2.1, or 1.0 to 1.1, or 1.0 to 1.2, or 1.0 to 1.3, or 1.0 to 1.4, or 1.0 to 1.5, or 1.0 to 1.6, or 1.0 to 1.7, or 1.0 to 1.8, or 1.0 to 1.9, or 1.0 to 2.0, or 1.0 to 2.1, or 1.1 to 1.2, or 1.1 to 1.3, or 1.1 to 1.4, or 1.1 to 1.5, or 1.1 to 1.6, or 1.1 to 1.7, or 1.1 to 1.8, or 1.1 to 1.9, or 1.1 to 2.0, or 1.1 to 2.1.

[0060] In one embodiment, or in combination with any other embodiment, category or subclass of this second aspect, the DS Pr is at least 0.1, at least 0.2, at least 0.3, at least 0.4, at least 0.5, at least 0.6, at least 0.7, at least 0.8, at least 0.9, at least 1.0, at least 1.1, at least 1.2, at least 1.3, or at least 1.4. Additionally, or in the alternative, the DS Pr is less than 1.5, less than 1.4, less than 1.3, less than 1.2, less than 1.1, less than 1.0, less than 0.9, less than 0.8, less than 0.7, less than 0.5, less than 0.4, or less than 0.3.

[0061] In one embodiment, or in combination with any other embodiment, category or subclass of this second aspect, the DSPr 1.05 to 1.35, or 1.05 to 1.3, or 1.05 to 1.25, or 1.05 to 1.2, or 1.05 to 1.15, or 1.05 to 1.1, or 1.1 to 1.4, or 1.1 to 1.35, or 1.1 to 1.3, or 1.1 to 1.25, or 1.1 to 1.2, or 1.1 to 1.15, or 1.15 to 1.4, or 1.15 to 1.35, or 1.15 to 1.3, or 1.15 to 1.25, or 1.15 to 1.2, or 1.2 to 1.4, or 1.2 to 1.35, or 1.2 to 1.3, or 1.2 to 1.25, or 1.25 to 1.4, or 1.25 to 1.35, or 1.25 to 1.3, or 1.3 to 1.4, or 1.3 to 1.35.

[0062] In one embodiment, or in combination with any other embodiment, category or subcategory of this second aspect, the DS OH at least 0.6, at least 0.7, at least 0.8, at least 0.9, at least 1.0, at least 1.1, at least 1.2, at least 1.3, at least 1.4, at least 1.5, at least 1.6, at least 1.7, at least 1.8, at least 1.9, at least 2.0, at least 2.1, at least 2.2, at least 2.3, at least 2.4, at least 2.5, or at least 2.6. Additionally, or in the alternative, the DS OH less than 2.8, less than 2.7, less than 2.6, less than 2.5, less than 2.4, less than 2.3, less than 2.2, less than 2.1, less than 2.0, less than 1.9, less than 1.8, less than 1.7, less than 1.6, less than 1.5, less than 1.4, less than 1.3, less than 1.2, less than 1.1, less than 1.0, less than 0.9, or less than 0.8.

[0063] In one embodiment, or in combination with any other embodiment, category or subcategory of this second aspect, the DS OH0.7 to 1.35, or 0.7 to 1.3, or 0.7 to 1.25, or 0.7 to 1.2, or 0.7 to 1.15, or 0.7 to 1.1, or 0.7 to 1.05, or 0.7 to 1.0, or 0.7 to 0.95, or 0.7 to 0.9, or 0.7 to 0.85, or 0.7 to 0.8, or 0.7 to 0.75, or 0.75 to 1.4, or 0.75 to 1.35, or 0.75 to 1.3, or 0.75 to 1.25, or 0.75 to 1.2, or 0.75 to 1.15, or 0.75 to 1.1, or 0.75 to 1.05, or 0.75 to 1.0, or 0.75 to 0.95, or 0.8 to 1.4, or 0.8 to 1.35, or 0.8 to 1.3, or 0.8 to 1.25, or 0.8 to 1.2, or 0.8 to 1.15, or 0.8 to 1.1, or 0.8 to 1.05, or 0.85 to 1.4, or 0.85 to 1.35, or 0.85 to 1.3, or 0.85 to 1.25, or 0.85 to 1.2, or 0.85 to 1.15, or 0.85 to 1.1, or 0.85 to 1.05, or 0.9 to 1.4, or 0.9 to 1.35, or 0.9 to 1.3, or 0.9 to 1.25, or 0.9 to 1.2, or 0.9 to 1.15, or 0.9 to 1.1, or 0.9 to 1.05.

[0064] In an embodiment, or in combination with any other embodiment, category or subclass of this second aspect, wherein DS Pr and the sum of DS Ac 1.65 to 2.3, or 1.65 to 2.2, or 1.65 to 2.1, or 1.65 to 2.0, or 1.65 to 1.9, or 1.65 to 1.8, or 1.7 to 2.3, or 1.7 to 2.2, or 1.7 to 2.1, or 1.7 to 2.0, or 1.7 to 1.9, or 1.7 to 1.8, or 1.75 to 2.3, or 1.75 to 2.2, or 1.75 to 2.1, or 1.75 to 2.0, or 1.75 to 1.9, or 1.8 to 2.3, or 1.8 to 2.2, or 1.8 to 2.1, or 1.8 to 2.0, or 1.8 to 1.9, or 1.9 to 2.3, or 1.9 to 2.2, or 1.9 to 2.1, or 1.9 to 2.0, or 2.0 to 2.3, or 2.0 to 2.2, or 2.0 to 2.1.

[0065] In an embodiment, or in combination with any other embodiment, category or subclass of this second aspect, wherein DS OH0.6 to 0.7, or 0.7 to 1.35, or 0.7 to 1.3, or 0.7 to 1.25, or 0.7 to 1.2, or 0.7 to 1.15, or 0.7 to 1.1, or 0.7 to 1.05, or 0.7 to 1.0, or 0.7 to 0.95, or 0.7 to 0.9, or 0.7 to 0.85, or 0.7 to 0.8, or 0.7 to 0.75, or 0.75 to 1.4, or 0.75 to 1.35, or 0.75 to 1.3, or 0.75 to 1.25, or 0.75 to 1.2, or 0.75 to 1.15, or 0.75 to 1.1, or 0.75 to 1.05, or 0.75 to 1.0, or 0.75 to 0.95, or 0.8 to 1.4, or 0.8 to 1.35, or 0.8 to 1.3, or 0.8 to 1.25, or 0.8 to 1.2, or 0.8 to 1.15, or 0.8 to 1.1, or 0.8 to 1.05, or 0.85 to 1.4, or 0.85 to 1.35, or 0.85 to 1.3, or 0.85 to 1.25, or 0.85 to 1.2, or 0.85 to 1.15, or 0.85 to 1.1, or 0.85 to 1.05, or 0.9 to 1.4, or 0.9 to 1.35, or 0.9 to 1.3, or 0.9 to 1.25, or 0.9 to 1.2, or 0.9 to 1.15, or 0.9 to 1.1, or 0.9 to 1.05.

[0066] In one embodiment, or in combination with any other embodiment, aspect or subclass of this second aspect, the mixed cellulose ester has a ratio of hydroxyl substituents to acetyl substituents of at least 0.4:1, at least 0.5:1, at least 0.6:1, at least 0.7:1, at least 0.8:1, at least 0.9:1, at least 1:1, at least 1.1:1, at least 1.2:1, at least 1.3:1, at least 1.4:1, at least 1.5:1, at least 1.6:1, at least 1.7:1, at least 1.8:1, at least 1.9:2, or at least 2:1. Additionally, in alternatives, the mixed cellulose ester has a ratio of hydroxyl substituents to acetyl substituents of less than 2:1, less than 1.9:1, less than 1.8:1, less than 1.7:1, less than 1.6:1, less than 1.5:1, less than 1.4:1, less than 1.3:1, less than 1.2:1, less than 1.1:1, or less than 1:1.

[0067] In an embodiment or in combination with any other embodiment, aspect, or subaspect of this second aspect, wherein the ratio of hydroxyl substituents to propionyl substituents of the MCE is at least 0.4: 1, at least 0.5: 1, at least 0.6: 1, at least 0.7: 1, at least 0.8: 1, at least 0.9: 1, at least 1: 1, at least 1.1: 1, at least 1.2: 1, at least 1.3: 1, at least 1.4: 1, at least 1.5: 1, at least 1.6: 1, at least 1.7: 1, at least 1.8: 1, at least 1.9: 2, or at least 2: 1, or at least 3: 1, or at least 4: 1. Additionally or in the alternative, the ratio of hydroxyl substituents to propionyl substituents of the MCE is less than 6: 1, less than 5: 1, less than 4: 1, less than 3: 1, less than 2: 1, less than 1.9: 1, less than 1.8: 1, less than 1.7: 1, less than 1.6: 1, less than 1.5: 1, less than 1.4: 1, less than 1.3: 1, less than 1.2: 1, less than 1.1: 1, or less than 1: 1.

[0068] In an embodiment or in combination with any other embodiment, aspect, or subaspect of this second aspect, wherein the MCE exhibits biodegradability of at least 40%, biodegradability of at least 45%, or biodegradability of at least 50%, or biodegradability of at least 55%, biodegradability of at least 60%, or biodegradability of at least 65%, or biodegradability of at least 70%, or biodegradability of at least 75%, or biodegradability of at least 80%, or biodegradability of at least 85% at 56 days according to at least one of the OECD 301B, OECD 301C, or OECD 301F test methods.

[0069] In an embodiment or in combination with any other embodiment, aspect, or subaspect of this second aspect, wherein the MCE exhibits biodegradability of at least 40%, biodegradability of at least 45%, or biodegradability of at least 50%, or biodegradability of at least 55%, biodegradability of at least 60%, or biodegradability of at least 65%, or biodegradability of at least 70%, or biodegradability of at least 75%, or biodegradability of at least 80%, or biodegradability of at least 85% at 60 days according to at least one of the OECD 301B, OECD 301C, or OECD 301F test methods.

[0070] In an embodiment or in combination with any other embodiment, class or subclass of this second aspect, the MCE has a weight average molecular weight in the range of 5,000 to 100,000 Da, or 5,000 to 50,000 Da, or 5,000 to 25,000 Da, or 15,000 to 100,000 Da, or 15,000 to 50,000 Da, or 15,000 to 25,000 Da, or 50,000 to 100,000 Da, or 75,000 to 100,000 Da, or 15,000 to 250,000 Da.

[0071] In a third aspect, the present application also discloses a mixed cellulose ester ("MCE") comprising: (1) a plurality of acetyl substituents; (2) a plurality of butyryl substituents; and (3) a plurality of hydroxyl substituents, wherein: the MCE has an average degree of substitution ("DS Ac ") of the acetyl substituents of 0.1 to 2.4, or 1.0 to 2.4, or 1.5 to 2.4, the MCE has an average degree of substitution ("DS Bu ") of the butyryl substituents of 0.1 to 1.5, or 0.1 to 0.6, or 0.1 to 0.3, and the MCE has an average degree of substitution ("DS OH ") of the hydroxyl substituents of 0.6 to 2.8, or 0.6 to 1.5, or 0.6 to 1.2.

[0072] In an embodiment or in combination with any other embodiment, class or subclass of this first aspect, the DS Ac is at least 0.1, at least 0.2, at least 0.3, at least 0.4, at least 0.5, at least 0.6, at least 0.7, at least 0.8, at least 0.9, at least 1.0, at least 1.1, at least 1.2, at least 1.3, at least 1.4, at least 1.5, at least 1.6, at least 1.7, at least 1.8, at least 1.9, or at least 2.0. Additionally, or in the alternative, the DS Ac is less than 2.3, less than 2.2, less than 2.1, less than 2.0, less than 1.9, less than 1.8, less than 1.7, less than 1.6, less than 1.5, less than 1.4, less than 1.3, less than 1.2, less than 1.1, less than 1.0, less than 0.9, less than 0.8, less than 0.7, less than 0.5, less than 0.4, or less than 0.3.

[0073] In an embodiment or in combination with any other embodiment, class or subclass of this third aspect, the DS Ac0.9 to 2.4, 0.9 to 2.3, or 0.9 to 2.2, or 0.9 to 2.1, or 0.9 to 2.0, or 0.9 to 1.9, or 0.9 to 1.8, or 0.9 to 1.7, or 0.9 to 1.6, or 0.9 to 1.4, 0.9 to 1.3, or 0.9 to 1.2, or 0.9 to 1.1, or 0.9 to 1.0, or 0.92 to 2.4, 0.92 to 2.3, or 0.92 to 2.2, or 0.92 to 2.1, or 0.92 to 2.0, or 0.92 to 1.9, or 0.92 to 1.8, or 0.92 to 1.7, or 0.92 to 1.6, or 0.92 to 1.4, 0.92 to 1.3, or 0.92 to 1.2, or 0.92 to 1.1, or 0.92 to 1.0, or 0.94 to 2.4, 0.94 to 2.3, or 0.94 to 2.2, or 0.94 to 2.1, or 0.94 to 2.0, or 0.94 to 1.9, or 0.94 to 1.8, or 0.94 to 1.7, or 0.94 to 1.6, or 0.94 to 1.4, 0.94 to 1.3, or 0.94 to 1.2, or 0.94 to 1.1, or 0.94 to 1.0, or 0.96 to 2.4, 0.96 to 2.3, or 0.96 to 2.2, or 0.96 to 2.1, or 0.96 to 2.0, or 0.96 to 1.9, or 0.96 to 1.8, or 0.96 to 1.7, or 0.96 to 1.6, or 0.96 to 1.4, 0.96 to 1.3, or 0.96 to 1.2, or 0.96 to 1.1, or 0.96 to 1.0, or 0.98 to 2.4, 0.98 to 2.3, or 0.98 to 2.2, or 0.98 to 2.1, or 0.98 to 2.0, or 0.98 to 1.9, or 0.98 to 1.8, or 0.98 to 1.7, or 0.98 to 1.6, 0.98 to 1.4, 0.98 to 1.3, or 0.98 to 1.2, or 0.98 to 1.1, or 0.98 to 1.0, or 1.0 to 2.4, 1.0 to 2.3, or 1.0 to 2.2, or 1.0 to 2.1, or 1.0 to 2.0, or 1.0 to 1.9, or 1.0 to 1.8, or 1.0 to 1.7, or 1.0 to 1.6, or 1.0 to 1.4, 1.0 to 1.3, or 1.0 to 1.2, or 1.0 to 1.1, or 1.1 to 2.4, or 1.1 to 2.3, or 1.1 to 2.2, or 1.1 to 2.1, or 1.1 to 2.0, or 1.1 to 1.9, or 1.1 to 1.8, or 1.1 to 1.7, or 1.1 to 1.6, 1.1 to 1.4, or 1.1 to 1.3, or 1.1 to 1.2, or 1.2 to 2.4, or 1.2 to 2.3, or 1.2 to 2.2, or 1.2 to 2.1, or 1.2 to 2.0, or 1.2 to 1.9, or 1.2 to 1.8, or 1.2 to 1.7, or 1.2 to 1.6, or 1.2 to 1.4, or 1.2 to 1.3, or 1.3 to 2.4, or 1.3 to 2.3, or 1.3 to 2.2, or 1.3 to 2.1, or 1.3 to 2.0, or 1.3 to 1.9, or 1.3 to 1.8, or 1.3 to 1.7, or 1.3 to 1.6, or 1.3 to 1.4, or 1.4 to 2.4, or 1.4 to 2.3, or 1.4 to 2.2, or 1.4 to 2.1, or 1.4 to 2.0, or 1.4 to 1.9, or 1.4 to 1.8, or 1.4 to 1.7, or 1.4 to 1.6, or 1.5 to 2.4, or 1.5 to 2.3, or 1.5 to 2.2, or 1.5 to 2.1, or 1.5 to 2.0, or 1.5 to 1.9, or 1.5 to 1.8, or 1.5 to 1.7, or 1.5 to 1.6, or 1.6 to 2.4, or 1.6 to 2.3, or 1.6 to 2.2, or 1.6 to 2.1, or 1.6 to 2.0, or 1.6 to 1.9, or 1.6 to 1.8, or 1.6 to 1.7, or 1.7 to 2.4, or 1.7 to 2.3, or 1.7 to 2.2, or 1.7 to 2.1, or 1.7 to 2.0, or 1.7 to 1.9, or 1.7 to 1.8, or 1.8 to 2.3, or 1.8 to 2.1, or 1.8 to 2.0, or 1.8 to 1.9, or 1.9 to 2.3, or 1.9 to 2.2, or 1.9 to 2.1, or 1.9 to 2.0, or 2.0 to 2.4, or 2.0 to 2.3, or 2.0 to 2.2, or 2.0 to 2.1, or 2.1 to 2.4, or 2.1 to 2.3, or 2.1 to 2.2, or 2.2 to 2.3.

[0074] In one embodiment, in combination with any other embodiment, class or subclass of this third aspect, wherein DS Bu is at least 0.05, at least 0.1, at least 0.15, at least 0.2, at least 0.3, at least 0.4, at least 0.5, at least 0.6, at least 0.7, at least 0.8, at least 0.9, at least 1.0, at least 1.1, at least 1.2, at least 1.3, or at least 1.4. Additionally, or in the alternative, DS Bu is less than 1.5, less than 1.4, less than 1.3, less than 1.2, less than 1.1, less than 1.0, less than 0.9, less than 0.8, less than 0.7, less than 0.5, less than 0.4, less than 0.35, less than 0.3, or less than 0.25.

[0075] In one embodiment, in combination with any other embodiment, class or subclass of this third aspect, wherein DS Bu0.1 to 1.35, or 0.1 to 1.3, or 0.1 to 1.25, or 0.1 to 1.2, or 0.1 to 1.15, or 0.1 to 1.1, or 0.1 to 1.0, or 0.1 to 0.8, or 0.1 to 0.6, or 0.1 to 0.5, or 0.1 to 0.4, or 0.1 to 0.3, or 0.1 to 0.25, or 0.15 to 1.35, or 0.15 to 1.3, or 0.15 to 1.25, or 0.15 to 1.2, or 0.15 to 1.15, or 0.15 to 1.1, or 0.15 to 1.0, or 0.15 to 0.8, or 0.15 to 0.6, or 0.15 to 0.5, or 0.15 to 0.4, or 0.15 to 0.3, or 0.15 to 0.25, or 0.2 to 1.35, or 0.2 to 1.3, or 0.2 to 1.25, or 0.2 to 1.2, or 0.2 to 1.15, or 0.2 to 1.1, or 0.2 to 1.0, or 0.2 to 0.8, or 0.2 to 0.6, or 0.2 to 0.4, or 0.3 to 1.35, or 0.3 to 1.3, or 0.3 to 1.25, or 0.3 to 1.2, or 0.3 to 1.15, or 0.3 to 1.1, or 0.3 to 1.0, or 0.3 to 0.8, or 0.3 to 0.6, or 0.3 to 0.5, or 0.4 to 1.35, or 0.4 to 1.3, or 0.4 to 1.25, or 0.4 to 1.2, or 0.4 to 1.15, or 0.4 to 1.1, or 0.4 to 1.0, or 0.4 to 0.8, or 0.4 to 0.6, or 0.5 to 1.35, or 0.5 to 1.3, or 0.5 to 1.25, or 0.5 to 1.2, or 0.5 to 1.15, or 0.5 to 1.1, or 0.5 to 1.0, or 0.5 to 0.8, or 0.5 to 0.7, or 0.6 to 1.35, or 0.6 to 1.3, or 0.6 to 1.25, or 0.6 to 1.2, or 0.6 to 1.15, or 0.6 to 1.1, or 0.6 to 1.0, or 0.6 to 0.8, or 0.7 to 1.35, or 0.7 to 1.3, or 0.7 to 1.25, or 0.7 to 1.2, or 0.7 to 1.15, or 0.7 to 1.1, or 0.7 to 1.0, or 0.8 to 1.35, or 0.8 to 1.3, or 0.8 to 1.25, or 0.8 to 1.2, or 0.8 to 1.15, or 0.8 to 1.1, or 0.8 to 1.0, or 0.9 to 1.35, or 0.9 to 1.3, or 0.9 to 1.25, or 0.9 to 1.2, or 0.9 to 1.15, or 0.9 to 1.1, or 1.0 to 1.35, or 1.0 to 1.3, or 1.0 to 1.25, or 1.0 to 1.2, or 1.0 to 1.15, or 1.0 to 1.1, or 1.05 to 1.35, or 1.05 to 1.3, or 1.05 to 1.25, or 1.05 to 1.2, or 1.05 to 1.15, or 1.05 to 1.1, or 1.1 to 1.4, or 1.1 to 1.35, or 1.1 to 1.3, or 1.1 to 1.25, or 1.1 to 1.2, or 1.1 to 1.15, or 1.15 to 1.4, or 1.15 to 1.35, or 1.15 to 1.3, or 1.15 to 1.25, or 1.15 to 1.2, or 1.2 to 1.4, or 1.2 to 1.35, or 1.2 to 1.3, or 1.2 to 1.25, or 1.25 to 1.4, or 1.25 to 1.35, or 1.25 to 1.3, or 1.3 to 1.4, or 1.3 to 1.35.

[0076] In one embodiment, or in combination with any other embodiment, class or subclass of this third aspect, the DS OH at least 0.5, at least 0.55, at least 0.6, at least 0.7, at least 0.8, at least 0.9, at least 1.0, at least 1.1, at least 1.2, at least 1.3, at least 1.4, at least 1.5, at least 1.6, at least 1.7, at least 1.8, at least 1.9, at least 2.0, at least 2.1, at least 2.2, at least 2.3, at least 2.4, at least 2.5, or at least 2.6. Additionally, or in the alternative, the DS OH less than 2.8, less than 2.7, less than 2.6, less than 2.5, less than 2.4, less than 2.3, less than 2.2, less than 2.1, less than 2.0, less than 1.9, less than 1.8, less than 1.7, less than 1.6, less than 1.5, less than 1.4, less than 1.3, less than 1.2, less than 1.1, less than 1.0, less than 0.9, less than 0.85, or less than 0.8.

[0077] In one embodiment, or in combination with any other embodiment, class or subclass of this third aspect, the DS OH0.5 to 1.3, 0.5 to 1.2, 0.5 to 1.1, 0.5 to 1.0, or 0.5 to 0.95, or 0.5 to 0.9, or 0.5 to 0.85, or 0.5 to 0.8, or 0.5 to 0.75, or 0.5 to 0.7, or 0.5 to 0.65, or 0.5 to 0.6, or 0.5 to 0.55, or 0.55 to 1.0, or 0.55 to 0.95, or 0.55 to 0.9, or 0.55 to 0.85, or 0.55 to 0.8, or 0.55 to 0.75, or 0.55 to 0.7, or 0.55 to 0.65, or 0.55 to 0.6, or 0.6 to 0.65, or 0.6 to 0.7, or 0.6 to 0.75, or 0.6 to 0.8, or 0.6 to 0.85, or 0.6 to 0.9, or 0.6 to 0.95, or 0.6 to 1.0, or 0.65 to 0.7, or 0.65 to 0.75, or 0.65 to 0.8, or 0.65 to 0.85, or 0.65 to 0.9, or 0.65 to 0.95, or 0.65 to 1.0.

[0078] In one embodiment, or in any other embodiment, class or subclass in combination herewith, wherein DS Bu and the sum of DS Ac is 1.65 to 2.3, or 1.65 to 2.2, or 1.65 to 2.1, or 1.65 to 2.0, or 1.65 to 1.9, or 1.65 to 1.8, or 1.7 to 2.3, or 1.7 to 2.2, or 1.7 to 2.1, or 1.7 to 2.0, or 1.7 to 1.9, or 1.7 to 1.8, or 1.75 to 2.3, or 1.75 to 2.2, or 1.75 to 2.1, or 1.75 to 2.0, or 1.75 to 1.9, or 1.8 to 2.3, or 1.8 to 2.2, or 1.8 to 2.1, or 1.8 to 2.0, or 1.8 to 1.9, or 1.9 to 2.3, or 1.9 to 2.2, or 1.9 to 2.1, or 1.9 to 2.0, 2.0 to 2.4, or 2.0 to 2.3, or 2.0 to 2.2, or 2.0 to 2.1.

[0079] In one embodiment, or in combination with any other embodiment, class or subclass of this third aspect, the mixed cellulose ester has a ratio of hydroxyl substituents to acetyl substituents of at least 0.4:1, at least 0.45:1, at least 0.5:1, at least 0.6:1, at least 0.7:1, at least 0.8:1, at least 0.9:1, at least 1:1, at least 1.1:1, at least 1.2:1, at least 1.3:1, at least 1.4:1, at least 1.5:1, at least 1.6:1, at least 1.7:1, at least 1.8:1, at least 1.9:2, or at least 2:1. Additionally, in the alternative, the mixed cellulose ester has a ratio of hydroxyl substituents to acetyl substituents of less than 2:1, less than 1.9:1, less than 1.8:1, less than 1.7:1, less than 1.6:1, less than 1.5:1, less than 1.4:1, less than 1.3:1, less than 1.2:1, less than 1.1:1, less than 1:1, less than 0.9:1, less than 0.8:1, less than 0.7:1, less than 0.6:1, or less than 0.5:1.

[0080] In one embodiment, or in combination with any other embodiment, class or subclass of this third aspect, the mixed cellulose ester has a ratio of hydroxyl substituents to butyryl substituents of at least 0.4:1, at least 0.5:1, at least 0.6:1, at least 0.7:1, at least 0.8:1, at least 0.9:1, at least 1:1, at least 1.1:1, at least 1.2:1, at least 1.3:1, at least 1.4:1, at least 1.5:1, at least 1.6:1, at least 1.7:1, at least 1.8:1, at least 1.9:2, at least 2:1, at least 3:1, or at least 4:1. Additionally, or in the alternative, the mixed cellulose ester has a ratio of hydroxyl substituents to butyryl substituents of less than 6:1, less than 5:1, less than 4:1, less than 3:1, less than 2:1, less than 1.9:1, less than 1.8:1, less than 1.7:1, less than 1.6:1, less than 1.5:1, less than 1.4:1, less than 1.3:1, less than 1.2:1, less than 1.1:1, or less than 1:1.

[0081] In one embodiment, or in combination with any other embodiment, class or subclass of this third aspect, the MCE exhibits biodegradability of at least 40% according to at least one of the OECD 301B, OECD 301C, or OECD 301F test methods at 56 days, biodegradability of at least 45%, or biodegradability of at least 50%, or biodegradability of at least 55%, or biodegradability of at least 60%, or biodegradability of at least 65%, or biodegradability of at least 70%, or biodegradability of at least 75%, or biodegradability of at least 80%, or biodegradability of at least 85%.

[0082] In an embodiment, or in combination with any other embodiment, class or subclass mentioned herein, the MCE exhibits biodegradability of at least 40%, biodegradability of at least 45%, or biodegradability of at least 50%, or biodegradability of at least 55%, biodegradability of at least 60%, or biodegradability of at least 65%, or biodegradability of at least 70%, or biodegradability of at least 75%, or biodegradability of at least 80%, or biodegradability of at least 85% according to at least one of the OECD 301B, OECD 301C, or OECD 301F test methods at 60 days.

[0083] In an embodiment, or in combination with any other embodiment, class or subclass of the third aspect mentioned herein, the MCE has a weight average molecular weight in the range of 5,000 to 100,000 Da, or 5,000 to 50,000 Da, or 5,000 to 25,000 Da, or 15,000 to 100,000 Da, or 15,000 to 50,000 Da, or 15,000 to 25,000 Da, or 50,000 to 100,000 Da, or 75,000 to 100,000 Da, or 15,000 to 250,000 Da.

[0084] In an embodiment, or in combination with any embodiment mentioned herein, the mixed cellulose ester of the first aspect, second aspect, and / or third aspect (including any class or subclass of these aspects) has a butyric acid content of less than 500, 400, 300, 200, 100, 50, 20, 10, 7.5, 5, 2.5, or 1 ppmw.

[0085] In an embodiment, or in combination with any embodiment mentioned herein, the mixed cellulose ester of the first aspect, second aspect, and / or third aspect (including any class or subclass of these aspects) has an acetic acid content of less than 500, 400, 300, 200, 100, 50, 20, 10, 7.5, 5, 2.5, or 1 ppmw.

[0086] In an embodiment, or in combination with any embodiment mentioned herein, the mixed cellulose ester of the first aspect, second aspect, and / or third aspect (including any class or subclass of these aspects) has a propionic acid content of less than 500, 400, 300, 200, 100, 50, 20, 10, 7.5, 5, 2.5, or 1 ppmw.

[0087] In an embodiment or in combination with any of the embodiments mentioned herein, the mixed cellulose ester of the first aspect, the second aspect, and / or the third aspect (including any category or subcategory of these aspects) has a sulfuric acid content of less than 500, 400, 300, 200, 100, 50, 20, 10, 7.5, 5, 2.5, or 1 ppmw.

[0088] In an embodiment or in combination with any of the embodiments mentioned herein, the CE 100 can be a mixed cellulose ester of the first aspect, the second aspect, and / or the third aspect (including any category or subcategory of these aspects).

[0089] Solvent system

[0090] The solvent system (e.g., solvent 102) is generally capable of dissolving the CE to produce the dispersed phase / solid phase of the emulsion / dispersion as described herein. In an embodiment or in combination with any of the embodiments mentioned herein, the solvent 102 can consist of a single solvent component, or can be a solvent system including multiple solvent components. The multiple solvent components can include at least two solvent components, at least three solvent components, or a total of three solvent components.

[0091] In an embodiment or in combination with any of the embodiments mentioned herein, the solvent 102 includes at least one, at least two, or all three of a C1-C4 alkyl acetate, a C1-C4 alcohol, and water. The C1-C4 alkyl acetate can include one or more of methyl acetate, ethyl acetate, n-propyl acetate, isopropyl acetate, n-butyl acetate, isobutyl acetate, sec-butyl acetate. The C1-C4 alcohol can include one or more of methanol, ethanol, propanol (e.g., isopropyl alcohol, n-propanol, and isopropyl alcohol), and butanol (e.g., n-butyl alcohol, isobutyl alcohol, sec-butyl alcohol, and t-butyl alcohol).

[0092] In an embodiment or in combination with any of the embodiments mentioned herein, when the solvent 102 includes more than one solvent component, the C1-C4 alkyl acetate can be present in one or more of the following amounts: (1) at least 10 wt%, 25 wt%, 50 wt%, 60 wt%, or 70 wt%; (2) no more than 99 wt%, 95 wt%, 90 wt%, 85 wt%, or 80 wt%; and (3) in a range of 10-99 wt%, 25-95 wt%, 50-90 wt%, 70-85 wt%.

[0093] In an embodiment or in combination with any of the embodiments mentioned herein, when solvent 102 comprises more than one solvent component, the C1-C4 alcohol is present in one or more of the following amounts: (1) at least 1 wt.%, 2 wt.%, 4 wt.%, 6 wt.%, 8 wt.%, or 10 wt.%; (2) no more than 80 wt.%, 60 wt.%, 40 wt.%, 30 wt.%, 20 wt.%, or 15 wt.%; and (3) in a range of 1-80 wt.%, 2-60 wt.%, 4-40 wt.%, 6-30 wt.%, 8-20 wt.%, or 10-15 wt.%.

[0094] In an embodiment or in combination with any of the embodiments mentioned herein, when solvent 102 comprises more than one solvent component, water is present in one or more of the following amounts: (1) at least 1 wt.%, 2 wt.%, 4 wt.%, 6 wt.%, or 8 wt.%; (2) no more than 50 wt.%, 25 wt.%, 20 wt.%, or 15 wt.%; and (3) in a range of 1-50 wt.%, 2-25 wt.%, 4-30 wt.%, 6-20 wt.%, or 8-15 wt.%.

[0095] In an embodiment or in combination with any of the embodiments mentioned herein, solvent 102 includes at least one, at least two, or all three of ethyl acetate, n-propanol, and water. In such an embodiment, ethyl acetate is present in an amount in a range of 50-90 wt.%, 55-90 wt.%, 60-90 wt.%, 65-90 wt.%, 65-85 wt.%, 70-85 wt.%, or 75-85 wt.%, n-propanol is present in an amount in a range of 4-40 wt.%, 5-35 wt.%, 6-30 wt.%, 7-25 wt.%, 8-20 wt.%, 10-20 wt.%, or 10-15 wt.%, and water is present in an amount in a range of 4-30 wt.%, 5-25 wt.%, 6-20 wt.%, 7-15 wt.%, 8-12 wt.%, or 9-12 wt.%.

[0096] Surprisingly, it has been discovered that water aids in and / or is capable of dissolving certain mixed cellulose esters. In particular, it has been discovered that water aids in and / or is capable of dissolving mixed cellulose esters having a high degree of biodegradability, such as those associated with a DS OH values greater than a determined threshold. These discoveries are disclosed in the Examples section below.

[0097] Hydrocolloids

[0098] A hydrocolloid, such as the hydrocolloid 106, as described herein, functions as a colloidal protectant and / or a viscosity builder. In an embodiment or in combination with any embodiment mentioned herein, the hydrocolloid 106 is a lyophilic colloid. For example, the hydrocolloid 106 can include at least one of a gelatin, a natural gum, a protein, or a cellulose derivative. The cellulose derivative can include one or both of methyl cellulose and carboxymethyl cellulose.

[0099] A hydrocolloid, such as carboxymethyl cellulose, can be selected based on a desired viscosity of the resulting aqueous mixture. In an embodiment or in combination with any embodiment mentioned herein, a "low" viscosity hydrocolloid has a viscosity in a range of between 10-50 cps, a "moderate" viscosity hydrocolloid has a viscosity in a range of between 400-800 cps, and a "high" viscosity hydrocolloid has a viscosity in a range of between 1500-3000 cps.

[0100] Surfactant system

[0101] In an embodiment or in combination with any embodiment mentioned herein, the surfactant 108 includes two or more separate emulsifiers. The separate emulsifiers can be distinguished based on their hydrophilic-lipophilic balance (HLB) values. For example, when the surfactant 108 includes two separate emulsifiers, the emulsifiers can include a lower HLB emulsifier and a higher HLB emulsifier.

[0102] In an embodiment or in combination with any embodiment mentioned herein, the higher HLB emulsifier has an HLB value of at least 6, 8, 10, 12, 14, 16, or 18, and the lower HLB emulsifier has an HLB value of no more than 12, 10, 8, 6, or 4.

[0103] In an embodiment or in combination with any embodiment mentioned herein, the higher HLB emulsifier has an HLB value that is at least one of the following higher than the HLB value of the lower HLB emulsifier: (1) at least 2, 4, 8, 10, 12, or 14; (2) no more than 25, 20, or 15; or (3) in a range of 2-25, 8-20, or 12-15.

[0104] In an embodiment or in combination with any embodiment mentioned herein, the lower HLB emulsifier is a glyceryl ester of stearic acid. In an embodiment or in combination with any embodiment mentioned herein, the higher HLB emulsifier is a secondary alcohol ethoxylate.

[0105] In one embodiment or in combination with any of the embodiments mentioned herein, the surfactant 108 further includes a third emulsifier. The third emulsifier has an HLB value that is greater than the HLB value of the lower HLB emulsifier. In one embodiment or in combination with any of the embodiments mentioned herein, the third emulsifier is a polyethylene glycol ester of stearic acid.

[0106] When the surfactant 108 is formed from all three emulsifiers, the lower HLB emulsifier and the third emulsifier can be present in a ratio of at least 0.25: 1, 0.5: 1, 0.75: 1, 1: 1, 1.25: 1, 1.5: 1, 1.75: 1, or 2: 1 and / or no more than 5: 1, 4: 1, 3: 1, 2: 1, 1.75: 1, 1.5: 1, or 1.25: 1. The lower HLB emulsifier and the third emulsifier can be defined as a combined emulsifier. Additionally, the higher HLB emulsifier and the combined emulsifier can be present in the surfactant 108 in a ratio of at least 0.25: 1, 0.5: 1, 0.75: 1, 1: 1, 1.25: 1, 1.5: 1, 1.75: 1, or 2: 1 and / or no more than 5: 1, 4: 1, 3: 1, 2: 1, 1.75: 1, 1.5: 1, or 1.25: 1.

[0107] Referring now to Figure 2 , the illustrated method for manufacturing the CE microparticles 112 includes separately forming the CE coating 136 and the aqueous mixture 138. The CE coating 136 and the aqueous mixture 138 are then combined to form the CE microparticles 112. For example, the CE coating 136 can be formed at unit 140 and the aqueous mixture 138 can be formed at unit 142. The CE coating 136 and the aqueous mixture 138 can then be combined at unit 144 to form an emulsion and / or dispersion, as will be described in greater detail below.

[0108] In one embodiment or in combination with any of the embodiments mentioned herein, the CE coating 136 is formed from the CE 100, the solvent 102, the water 104, and, in some embodiments, the recycled solvent 146 derived from the solvent-rich stream 134.

[0109] In one embodiment or in combination with any of the embodiments mentioned herein, the CE 100 is present in the CE coating in one or more of the following: (1) at least 1 wt.%, 2 wt.%, 4 wt.%, 6 wt.%, 8 wt.%, or 10 wt.%; (2) no more than 80 wt.%, 60 wt.%, 40 wt.%, 30 wt.%, 20 wt.%, or 15 wt.%; and (3) in a range of 1-80 wt.%, 2-60 wt.%, 4-40 wt.%, 6-30 wt.%, 8-20 wt.%, or 10-15 wt.%.

[0110] In an embodiment or in combination with any of the embodiments mentioned herein, when solvent 102 comprises a C1-C4 alkyl acetate, the C1-C4 alkyl acetate is present in the CE coating 136 in one or more of the following amounts: (1) at least 10, 25, 50, 60, or 65 weight percent; (2) no more than 95, 90, 85, 80, or 75 weight percent; and (3) in a range of 10-95, 25-90, 50-85, or 65-75 weight percent.

[0111] In an embodiment or in combination with any of the embodiments mentioned herein, when solvent 102 comprises a C1-C4 alcohol, the C1-C4 alcohol is present in the CE coating 136 in one or more of the following amounts: (1) at least 1, 2, 4, 6, or 8 weight percent; (2) no more than 50, 25, 20, or 15 weight percent; and (3) in a range of 1-50, 2-25, 4-30, 6-20, or 8-15 weight percent.

[0112] In an embodiment or in combination with any other embodiment, the ratio of solvent used to dissolve to form the CE coating 136 to the CE is at least 1:1, 2:1, 3:1, 4:1, or 5:1 and / or no more than 100:1, 50:1, 25:1, or 10:1.

[0113] In an embodiment or in combination with any of the embodiments mentioned herein, when solvent 102 comprises water, the water is present in the CE coating 136 in one or more of the following amounts: (1) at least 0.5, 1, 2, 4, or 6 weight percent; (2) no more than 40, 25, 15, or 10 weight percent; and (3) in a range of 0.5-40, 1-25, 2-15, 4-20, or 6-10 weight percent.

[0114] In a particular embodiment, the CE coating 136 is formed from the CE 100, the solvent 102 comprising ethyl acetate and n-propanol, and the water 104. In such an embodiment, the CE is present in the CE coating 136 in an amount in the range of 6-30 wt.%, 7-25 wt.%, 8-20 wt.%, 9-20 wt.%, 10-15 wt.%, or 12-15 wt.%, the ethyl acetate is present in the CE coating 136 in an amount in the range of 50-85 wt.%, 55-85 wt.%, 60-85 wt.%, 65-85 wt.%, 70-85 wt.%, or 75-85 wt.%, the n-propanol is present in the CE coating 136 in an amount in the range of 4-30 wt.%, 6-25 wt.%, 8-20 wt.%, 10-20 wt.%, or 12-15 wt.%, and the water is present in the CE coating 136 in an amount in the range of 4-20 wt.%, 5-18 wt.%, 6-16 wt.%, 7-14 wt.%, or 8-12 wt.%.

[0115] In one embodiment or in combination with any of the embodiments mentioned herein, the CE 100, the solvent 102, and the water 104 are combined at the unit 140 until substantially homogeneous to produce the CE coating 136. In one embodiment or in combination with any of the embodiments mentioned herein, the components are mixed at room temperature (e.g., at least 15°C, 20°C, 25°C, or 30°C and / or not more than 45°C, 40°C, 35°C, 30°C, 25°C, or 20°C) for a duration of at least 1, 2, 5, 10, 15, 20, 25, 30, 45, 60, 120, or 240 minutes and / or for a time necessary to produce a substantially homogeneous mixture.

[0116] In one embodiment or in combination with any of the embodiments mentioned herein, the aqueous mixture 138 is formed from the water 104, the hydrocolloid 106, the surfactant 108, and, in some embodiments, the recycled solvent 146 derived from the solvent-rich stream 134. Optionally, additional solvent 148 can be added to the units 140 and / or 142 as needed to maintain the concentration of the solvent components at a suitable level.

[0117] In one embodiment or in combination with any of the embodiments mentioned herein, the ratio of recycled solvent portion to fresh solvent portion used in the units 140 and / or 142 is at least 2.5: 1, 10: 1, 25: 1, 50: 1, 75: 1, 90: 1, 95: 1, or 99: 1 by weight and / or not more than 1000: 1, 500: 1, 200: 1, or 100: 1 by weight.

[0118] In an embodiment or in combination with any of the embodiments mentioned herein, the compositional make-up of the recycled solvent differs from the compositional make-up of the fresh solvent by no more than 10 wt%, 5 wt%, 2 wt%, or 1 wt% in total.

[0119] In an embodiment or in combination with any of the embodiments mentioned herein, the fresh solvent and the recycled solvent portion have substantially the same composition.

[0120] In an embodiment or in combination with any of the embodiments mentioned herein, water is present in the aqueous mixture 138 in one or more of the following amounts: (1) at least 40 wt%, 60 wt%, 70 wt%, 80 wt%, or 85 wt%; (2) no more than 99 wt%, 97 wt%, 95 wt%, 94 wt%, or 92 wt%; and (3) in a range of 40-99 wt%, 70-95 wt%, or 85-92 wt%.

[0121] In an embodiment or in combination with any of the embodiments mentioned herein, hydrocolloid is present in the aqueous mixture 138 in one or more of the following amounts: (1) at least 0.001 wt%, 0.005 wt%, 0.01 wt%, 0.05 wt%, or 0.1 wt%; (2) no more than 15 wt%, 10 wt%, 5 wt%, 2 wt%, or 1 wt%; and (3) in a range of 0.001-15 wt%, 0.01-5 wt%, or 0.1-2 wt%.

[0122] In an embodiment or in combination with any of the embodiments mentioned herein, surfactant is present in the aqueous mixture 138 in one or more of the following amounts: (1) at least 0.005 wt%, 0.01 wt%, 0.05 wt%, 0.1 wt%, or 0.5 wt%; (2) no more than 15 wt%, 10 wt%, 5 wt%, 2 wt%, or 1.5 wt%; and (3) in a range of 0.005-15 wt%, 0.05-5 wt%, or 0.5-1.5 wt%.

[0123] As described above, the surfactants described herein can include a higher HLB emulsifier and a lower HLB emulsifier. In such embodiments, the higher HLB emulsifier and the lower HLB emulsifier are present in the aqueous mixture 138 in a high HLB emulsifier to low HLB emulsifier ratio in a range of at least 0.25: 1, 0.5: 1, 1: 1, 1.5: 1, or 1.75: 1 and / or no more than 10: 1, 5: 1, 3: 1, or 2.5: 1 and / or in a range of 0.25: 1-10: 1, 0.5: 1-5: 1, or 1: 1-3: 1.

[0124] Reference is again made to Figure 2 In some embodiments, additional solvent 148 and / or recycled solvent 146 is received at unit 142. In such embodiments, the solvent used to form the CE coating 136 and aqueous mixture 138 is a common C1-C4 alkyl acetate. The use of at least one common component in the solvent system received at units 140 and 142 facilitates simplification of the separation, recovery, and reuse of solvents as described herein.

[0125] In one embodiment or in combination with any of the embodiments mentioned herein, when the aqueous mixture 138 comprises a C1-C4 alkyl acetate, the C1-C4 alkyl acetate is present in the aqueous mixture 138 in one or more of the following amounts: (1) at least 1 wt.%, 2 wt.%, 4 wt.%, 6 wt.%, or 8 wt.%; (2) no more than 50 wt.%, 40 wt.%, 30 wt.%, 20 wt.%, or 15 wt.%; and (3) in a range of 1-50 wt.%, 2-40 wt.%, or 6-20 wt.%.

[0126] In one embodiment or in combination with any of the embodiments mentioned herein, the C1-C4 alkyl acetate is present in the aqueous mixture 138 in an amount (in wt.%) that is within 25 wt.%, 20 wt.%, 15 wt.%, 10 wt.%, 5 wt.%, or 2 wt.% (in wt.%) of the solubility of the C1-C4 alkyl acetate in water at 20 °C (in wt.%).

[0127] The C1-C4 alkyl acetate can be one or both of methyl acetate and ethyl acetate. In one embodiment or in combination with any of the embodiments mentioned herein, when the C1-C4 alkyl acetate is ethyl acetate, the ethyl acetate is present in the aqueous mixture in an amount in a range of 2-25 wt.%, 4-20 wt.%, 6-15 wt.%, or 8-10 wt.%. In one embodiment or in combination with any of the embodiments mentioned herein, when the C1-C4 alkyl acetate is methyl acetate, the methyl acetate is present in the aqueous mixture in an amount in a range of 5-50 wt.%, 10-40 wt.%, 15-35 wt.%, or 20-30 wt.%.

[0128] In a particular embodiment, the aqueous mixture 138 is formed from water 104, hydrocolloid 106, surfactant 108, and C1-C4 alkyl acetate. In such an embodiment, the water is present in the aqueous mixture 138 in an amount in the range of 70-95 wt.%, 75-95 wt.%, 80-95 wt.%, 85-95 wt.%, or 87.5-92.5 wt.%, the hydrocolloid is present in the aqueous mixture 138 in an amount in the range of 0.01-5 wt.%, 0.1-4 wt.%, 0.5-3 wt.%, 0.6-2 wt.%, 0.7-1 wt.%, or 0.8-0.9 wt.%, the surfactant is present in the aqueous mixture 138 in an amount in the range of 0.05-5 wt.%, 0.1-5 wt.%, 0.1-4 wt.%, 0.5-3 wt.%, 0.6-2 wt.%, 0.7-1 wt.%, or 0.8-1 wt.%, and the C1-C4 alkyl acetate is present in the aqueous mixture 138 in an amount in the range of 2-40 wt.%, 3-35 wt.%, 4-30 wt.%, 5-25 wt.%, 5-20 wt.%, 5-15 wt.%, 5-10 wt.%, or 6-10 wt.%.

[0129] In an embodiment or in combination with any of the embodiments mentioned herein, the water 104, hydrocolloid 106, surfactant 108, and optional C1-C4 alkyl acetate are combined at unit 142 to produce the aqueous mixture 138. In an embodiment or in combination with any of the embodiments mentioned herein, the components are mixed at a temperature of at least 15°C, 20°C, 25°C, 30°C, 35°C, 40°C, 45°C, or 50°C and / or no more than 100°C, 75°C, 50°C, 40°C, 35°C, 30°C, 25°C, or 20°C for a duration of at least 1, 2, 5, 10, 15, 20, 25, 30, 45, 60, 120, or 240 minutes and / or for a time necessary to produce a substantially homogenous mixture, depending on the viscosity of the hydrocolloid used.

[0130] Emulsion / dispersion formation

[0131] Once formed, the CE coating 136 and the aqueous mixture 138 can be combined at unit 144 to produce an emulsion and / or dispersion, as described above.

[0132] In an embodiment or in combination with any of the embodiments mentioned herein, the ratio of the CE coating 136 to the aqueous mixture 138 combined at unit 144 to form the initial emulsion is at least 0.05:1 to 10:1, 0.1:1 to 5:1, 0.2:1 to 2:1, or 0.4:1 to 0.8:1.

[0133] In an embodiment or in combination with any of the embodiments mentioned herein, the initial emulsion comprises water in an amount of at least 10 wt.%, 20 wt.%, 30 wt.%, 40 wt.%, 50 wt.% or 60 wt.% and / or not more than 90 wt.%, 80 wt.%, 70 wt.%, 60 wt.%, 50 wt.% or 40 wt.%.

[0134] Once combined, the initial emulsion is converted to a pre-hardened dispersion comprising a solid phase and a liquid phase. This conversion can be performed by at least one of shearing, spraying (ultrasonic or electric) and membrane emulsification.

[0135] In an embodiment or in combination with any of the embodiments mentioned herein, the combined CE coating and aqueous mixture are circulated through a high shear mixer to disperse the solid phase within the liquid phase and to promote hardening of the solid phase to produce initial microparticles. This shearing can be performed as the CE coating 136 and aqueous mixture 138 are fed into the unit 144 and / or can be performed after a predetermined amount of CE coating 136 and aqueous mixture 138 are within the unit 144.

[0136] In an embodiment or in combination with any of the embodiments mentioned herein, the combined CE coating and aqueous mixture are circulated through a high shear mixer for at least 1, 2, 3, 4 or 5 residence times and / or not more than 20, 15, 10, 9 or 8 residence times (based on the total volume of the high shear mixer used). In addition, the high shear mixing is performed for a duration of at least 1, 2, 5, 10, 15, 20, 25, 30, 45, 60, 120 or 240 minutes and / or for up to the time required to circulate the volume of the mixture a predetermined number of residence times.

[0137] To produce the initial microparticles that will form the CE microparticles as described herein, the combined CE coating and aqueous mixture is agitated in unit 144. The agitation performed at unit 144 can be quantified by at least one of: (1) impeller tip speed, (2) impeller Reynolds number, and (3) power mass ratio. In one embodiment or in combination with any embodiment mentioned herein, the high shear mixing is performed at an impeller tip speed of at least 25, 50, 75, 100, 150, 200, 250, or 300 cm / s, and / or no more than 1000, 500, 400, 300, 200, or 100 cm / s. In one embodiment or in combination with any embodiment mentioned herein, the high shear mixing is performed at an impeller Reynolds number of at least 500, 1000, 1500, 2000, 3000, 4000, 5000, or 6000, and / or no more than 15000, 10000, 8000, 6000, 5000, 4000, or 3000. In one embodiment or in combination with any embodiment mentioned herein, the high shear mixing is performed at a power mass ratio of at least 0.01, 0.02, 0.03, 0.1, 0.5, 1.0, 1.5, 2.0, 2.5, or 3.0, and / or no more than 10.0, 7.5, 5.0, 4.0, 3.0, 2.5, 2.0, 1.5, 1.0, 0.5, or 0.1.

[0138] As used herein, terms such as "solid," "solid phase," "particles," and "microparticles" refer to a semi-solid material that does not lose its discrete nature (i.e., flow together) when the aqueous phase / continuous phase surrounding the material is removed.

[0139] Hardening with an extractant

[0140] The pre-hardened dispersion 150 formed at unit 144 and comprising the initial microparticles (i.e., solid phase) can be directed to a hardening unit 152 to convert the initial particles to hardened CE microparticles 112. At unit 152, the initial microparticles contained within the pre-hardened dispersion 150 are contacted with an extractant 154 (i.e., a drowning liquid) to produce a hardened dispersion 156. That is, the contacting step facilitates desolvation and hardening of the initial microparticles into CE microparticles. In one embodiment or in combination with any embodiment mentioned herein, the extractant is water. Alternatively, the extractant can be methanol, ethanol, and combinations thereof.

[0141] In one embodiment or in combination with any embodiment mentioned herein, the pre-hardened dispersion and the extractant are combined at unit 152 at an extractant to dispersion weight ratio of at least 0.5: 1, 1: 1, 1.5: 1, 2: 1, or 1.5: 1, and / or no more than 10: 1, 8: 1, 6: 1, 4: 1, or 3: 1.

[0142] In an embodiment or in combination with any of the embodiments mentioned herein, the weight ratio of the extractant used in the contacting step to the pre-hardened particles is at least 2: 1, 5: 1, 10: 1, 20: 1, 30: 1, or 40: 1, and / or no more than 200: 1, 100: 1, 80: 1, 60: 1, or 50: 1.

[0143] Thus, in an embodiment or in combination with any of the embodiments mentioned herein, the hardened dispersion 156 has water in an amount of one or more of: (1) at least 25 wt%, 50 wt%, 60 wt%, 70 wt%, 80 wt%, 85 wt%, or 90 wt%; (2) no more than 99 wt%, 97.5 wt%, 95 wt%, 92.5 wt%, 90 wt%, 80 wt%, 70 wt%, 60 wt%, or 50 wt%; and (3) in a range of 50-99 wt%, 70-95 wt%, or 80-92.5 wt%.

[0144] In an embodiment or in combination with any of the embodiments mentioned herein, the hardened dispersion 156 has water in an amount of one or more of: (1) at least 25 wt%, 50 wt%, 60 wt%, 70 wt%, 80 wt%, 85 wt%, or 90 wt%; (2) no more than 99 wt%, 97.5 wt%, 95 wt%, 92.5 wt%, 90 wt%, 80 wt%, 70 wt%, 60 wt%, or 50 wt%; and (3) in a range of 50-99 wt%, 70-95 wt%, or 80-92.5 wt%.

[0145] In an embodiment or in combination with any of the embodiments mentioned herein, the hardening of the microparticles is performed under agitation. The agitation performed at unit 152 can be quantified by at least one of: (1) an impeller tip speed, (2) an impeller Reynolds number, and (3) a power mass ratio. In an embodiment or in combination with any of the embodiments mentioned herein, the conversion / hardening is performed at an impeller tip speed of at least 25, 50, 75, 100, 150, 200, 250, or 300 cm / s, and / or no more than 1000, 500, 400, 300, 200, or 100 cm / s. In an embodiment or in combination with any of the embodiments mentioned herein, the conversion / hardening is performed at an impeller Reynolds number of at least 500, 1000, 1500, 2000, 3000, 4000, 5000, or 6000, and / or no more than 15000, 10000, 8000, 6000, 5000, 4000, or 3000. In an embodiment or in combination with any of the embodiments mentioned herein, the conversion / hardening is performed at a power mass ratio of at least 0.01, 0.02, 0.03, 0.1, 0.5, 1.0, 1.5, 2.0, 2.5, or 3.0, and / or no more than 10.0, 7.5, 5.0, 4.0, 3.0, 2.5, 2.0, 1.5, 1.0, 0.5, or 0.1.

[0146] Further, the converting / hardening is performed for a period of at least 0.1, 0.5, 1, 2, 4, 6, 8, 10, or 20 minutes, and / or no more than 12, 8, 6, 4, or 2 hours, and at a temperature of at least 0°C, 5°C, or 10°C, and / or no more than 100°C, 75°C, 50°C, or 25°C.

[0147] In one embodiment or in combination with any of the embodiments mentioned herein, the converting / hardening is performed in a single vessel or multiple vessels. Multiple vessels can be required based on the yield of CE microparticles to be produced and the volumetric capacity of the available vessels for hardening. In embodiments where multiple vessels are used, a first portion of the pre-hardened dispersion 150 can be received at a first hardening unit, and a second portion of the pre-hardened dispersion can be received at a second hardening unit. Flow communication can then be provided between the separate hardening units to enhance mass transfer, such that desolvation of the initial microparticles is accelerated.

[0148] In one embodiment or in combination with any of the embodiments mentioned herein, the pre-hardened dispersion 150 has a solids content of at least 0.5 wt.%, 1 wt.%, 2 wt.%, 3 wt.%, or 4 wt.%, and / or no more than 40 wt.%, 30 wt.%, 20 wt.%, 10 wt.%, or 6 wt.%.

[0149] As a result of the hardening, in one embodiment or in combination with any of the embodiments mentioned herein, the hardened dispersion 156 has a solids content of at least 0.05 wt.%, 0.1 wt.%, 0.5 wt.%, or 1 wt.%, and / or no more than 20 wt.%, 10 wt.%, 5 wt.%, 2 wt.%, or 1 wt.%.

[0150] In one embodiment or in combination with any of the embodiments mentioned herein, the solids content of the pre-hardened dispersion is at least 1.5, 2, 3, or 4 times, and / or no more than 20, 10, 8, or 6 times, the solids content of the hardened dispersion. In other words, at unit 152, solvent is extracted from the initial microparticles to produce a hardened dispersion 156 comprising hardened CE microparticles 112 and a solvent-saturated drowning liquid.

[0151] CE microparticle isolation / separation

[0152] Any suitable technique can be employed at unit 158 to separate and recover the CE particulates 112 from the hardened dispersion 156. In one embodiment or in combination with any embodiment mentioned herein, the separation can be performed by at least one, at least two, or all three of: (1) flashing one or more liquid components out of the hardened CE particulates; (2) filtering the hardened CE particulates out of one or more liquid components; and (3) centrifuging, redispersing, and drying the hardened particulates.

[0153] Solid processing and / or CE particulate separation can be performed in a single unit as illustrated in Figure 1 or in multiple units as illustrated in Figure 2 . See Figure 2 , a wet solid stream 160 and a separated mother liquor stream 162 are discharged from unit 158. The wet solid stream 160 contains the hardened CE particulates and residual liquid. In one embodiment or in combination with any embodiment mentioned herein, the wet solid stream 160 has a solids content of at least 10 wt.%, 20 wt.%, 25 wt.%, 30 wt.%, 35 wt.%, 40 wt.%, or 45 wt.% and / or no more than 60 wt.%, 65 wt.%, 50 wt.%, 45 wt.%, or 40 wt.%. This enables the wet solid stream 160 to be passed to downstream units while reducing clogging and processing issues.

[0154] The wet solid stream 160 can then be optionally processed in a washing unit 164 and a second solid / liquid separation unit 166. At unit 164, the hardened CE particulates are washed with water 122 to produce a washed solid stream 168. The washed solid stream 168 is then processed at unit 166 by at least one, at least two, or all three of: (1) flashing one or more liquid components out of the hardened CE particulates; (2) filtering the hardened CE particulates out of one or more liquid components; and (3) centrifuging, redispersing, and drying the hardened particulates. This second solid / liquid separation step facilitates reducing the solvent content in the liquid surrounding the hardened CE particulates.

[0155] The wash liquid 130 can be recovered from the second solid / liquid separation step and then recycled for use as at least a portion of the aqueous mixture in unit 142 and / or for use as at least a portion of the flooding liquid in unit 152.

[0156] In one embodiment or in combination with any embodiment mentioned herein, at least 1 wt.%, 5 wt.%, or 10 wt.% and / or no more than 90 wt.%, 50 wt.%, 20 wt.%, or 10 wt.% of the aqueous mixture 138 is recycled wash liquid.

[0157] In one embodiment or in combination with any of the embodiments mentioned herein, at least 1 wt.%, 5 wt.% or 10 wt.% and / or no more than 90 wt.%, 50 wt.%, 20 wt.% or 10 wt.% of the flooding liquid 154 used in the unit 152 is the recycled wash liquid.

[0158] The wet solids stream 172 exiting the unit 166 is then received at a drying unit 170. In one embodiment or in combination with any of the embodiments mentioned herein, the drying is conducted at the unit 170 under agitation and with the addition of heat. Such agitation is beneficial to reduce the aggregation of the recovered CE particulates 112. The properties of the recovered CE particulates 112 will be described in greater detail below.

[0159] In one embodiment or in combination with any of the embodiments mentioned herein, the drying unit 170 is a rotary cone dryer.

[0160] Liquid processing and recycling

[0161] The separated mother liquor stream 162 exiting the unit 164 can be processed to recover water and / or solvent. The recovered water and / or solvent can then be recycled to Figure 2 one or more of the units shown in to improve the economic efficiency of the particulate formation process described herein.

[0162] Figure 1 The liquid processing can be conducted in a single unit as illustrated in Figure 2 or in multiple units as illustrated in Figure 2 See, for example, the mother liquor stream 162 contains at least a portion of the water introduced at the units 140 and / or 142 and at least a portion of the solvent. The mother liquor stream 162 can also contain residual amounts of hydrocolloid, surfactant and any components used to manufacture the mixed cellulose ester.

[0163] The mother liquor stream 162 can be heated 174 and then separated at a unit 176 into at least two separate streams, such as the solvent-rich stream 134 and the water-rich (solvent-lean) stream 132. The mother liquor stream 162 can be separated at the unit 176 using any suitable technique. In one embodiment or in combination with any of the embodiments mentioned herein, the liquid separation can be conducted by distillation or the like.

[0164] In one embodiment or in combination with any of the embodiments mentioned herein, the water-rich stream 132 comprises one or more of: (1) water; (2) surfactant; (3) hydrocolloid; and (4) C1-C4 alkyl acetate.

[0165] Accordingly, the water-rich stream 132 can be cooled 181 and then recycled to Figure 2one or more units illustrated in FIG. 1. For example, the composition of the water-rich stream 132 enables it to be recycled as stream 178 to at least one of the units 142 for forming the aqueous mixture 138 and / or as stream 180 to the unit 152 for desolvation of the initial particulates, thereby reducing the amount of water required for such a process. For example, any excess material not required by these processes can be purged from the system and subjected to waste water treatment.

[0166] In an embodiment or in combination with any embodiment mentioned herein, the ratio of recycled water in stream 180 used in the hardening step to recycled water in stream 178 used in forming the aqueous mixture 138 is at least 1 : 1, 1.5: 1, 2: 1, 3: 1, 4: 1, and / or no more than 20: 1, 10: 1, 8: 1, or 6: 1.

[0167] In an embodiment or in combination with any embodiment mentioned herein, the ratio of recycled water in stream 180 used in the hardening step to purified water is at least 1 : 1, 1.5: 1, 2: 1, 3: 1, 4: 1, and / or no more than 20: 1, 10: 1, 8: 1, or 6: 1.

[0168] In an embodiment or in combination with any embodiment mentioned herein, at least 75 wt%, 90 wt%, 95 wt%, 98 wt%, 99 wt%, or 100 wt% of the extractant used in the unit 152 is recycled water recovered downstream from the unit 152, such as the water contained in the water-rich stream 132 recycled to the unit 152.

[0169] In an embodiment or in combination with any embodiment mentioned herein, fresh water 154 is added to the unit 152 for the hardening step.

[0170] In an embodiment or in combination with any embodiment mentioned herein, the ratio of the total amount of fresh water added to the total amount of purified water is at least 0.25: 1, 0.5: 1, 0.75: 1, or 0.9: 1, and / or no more than 4: 1, 2: 1, 1.5: 1, 1.25: 1, or 1.1: 1.

[0171] In an embodiment or in combination with any embodiment mentioned herein, the solvent-rich stream 134 comprises one or more of: (1) a C1-C4 alkyl acetate; (2) a C1-C4 alcohol; and (3) water.

[0172] Accordingly, the solvent-rich stream 134 can be recycled to Figure 2one or more units illustrated in the middle. For example, the composition of the solvent-rich stream 134 enables it to be recycled to at least one of the units 140 for use as part of the solvent in the formation of the CE coating 136 and / or to the unit 142 for use in forming the aqueous mixture 138. Any excess material not required by these processes can be purged from the system.

[0173] In one embodiment or in combination with any of the embodiments mentioned herein, at least 75 wt%, 90 wt%, 95 wt%, 98 wt%, 99 wt%, or 100 wt% of the solvent used in the unit 140 for forming the CE coating 136 is recycled solvent 146.

[0174] In one embodiment or in combination with any of the embodiments mentioned herein, fresh water 104 is added to the unit 142 for forming the aqueous mixture 138.

[0175] In one embodiment or in combination with any of the embodiments mentioned herein, the ratio of the combined amount of water in streams 178 and 180 to the total amount of fresh water 104 added in the unit 142 is at least 2: 1, 4: 1, 6: 1, or 8: 1.

[0176] In one embodiment or in combination with any of the embodiments mentioned herein, the aqueous mixture 138 comprises azeotropes of water and C1-C4 alkyl acetate and / or azeotropes of water and C1-C4 alcohol derived from the water-rich stream 132.

[0177] Hydroxyl groups are typically strong hydrogen bonders. Thus, as the DS OH of a given material increases, the opportunity for hydrogen bonding also increases. The cosolvent alcohols of the solvent systems described herein are also strong hydrogen bonders. Surprisingly, however, it was found that the ability of the cosolvent alcohols to form hydrogen bonds decreases as the number of carbon atoms (i.e., C1-C4) increases. Thus, it was found that lower carbon number binary solvent systems without water were able to dissolve cellulose esters having a DS OH greater than a biodegradability threshold (e.g., a DS OH greater than 0.8). In contrast, it was found that higher carbon number binary solvent systems without water were not able to dissolve cellulose esters having a DS OH greater than the same biodegradability threshold. Thus, it has been found that the presence of a strong hydrogen bonder (i.e., water) with essentially no steric hindrance is beneficial to the dissolution of the mixed CE in the solvent systems described herein in solvent systems containing higher carbon number alcohols.

[0178] In an embodiment or in combination with any of the embodiments mentioned herein, the recycled solvent 146 contains water in an amount of at least 1 wt%, 2 wt%, 4 wt%, 6 wt%, or 8 wt%, and / or no more than 50 wt%, 40 wt%, 30 wt%, 20 wt%, or 10 wt%.

[0179] In an embodiment or in combination with any of the embodiments mentioned herein, the recycled solvent 146 contains at least one azeotrope, wherein the azeotrope contains water and another component.

[0180] In an embodiment or in combination with any of the embodiments mentioned herein, the azeotrope can be in the recycled solvent 146, can be a water / alcohol azeotrope, a water / alkyl acetate azeotrope, or both a water / alcohol azeotrope and a water / alkyl acetate azeotrope.

[0181] In an embodiment or in combination with any of the embodiments mentioned herein, the recycled solvent 146 contains multiple azeotropes. In an embodiment or in combination with any of the embodiments mentioned herein, the multiple azeotropes include multiple binary azeotropes. In an embodiment or in combination with any of the embodiments mentioned herein, the components of the solvent system are selected such that the recycled solvent 146 does not contain any ternary azeotropes, thereby simplifying the recovery and recycling of the solvent.

[0182] In an embodiment or in combination with any of the embodiments mentioned herein, the rich solvent stream 134 contains less than 10 wt%, less than 1 wt%, less than 0.1 wt%, or 0.0 wt% of a ternary azeotrope.

[0183] In an embodiment or in combination with any of the embodiments mentioned herein, the recycled solvent 146 contains a total of three binary azeotropes, such as a water / alcohol azeotrope, a water / alkyl acetate azeotrope, and an alcohol / alkyl acetate azeotrope.

[0184] Additional embodiments

[0185] Reference is now made to Figure 3 , the CE microparticles 112 are produced by continuous particle formation. In an example embodiment, particle formation begins at unit 142, where water 104, hydrocolloid 106, surfactant 108, and, in some embodiments, recycled solvent 146 derived from rich solvent stream 134 are combined to form aqueous mixture 138.

[0186] The aqueous mixture 138 is discharged from unit 142 and received at a dispersion formation unit 182. At unit 182, the aqueous mixture 138 is combined with the CE 100, the solvent 102, and optionally the recycled solvent 146 from the solvent-rich stream 134. Thus, rather than forming the CE coating 136 and the aqueous mixture 138 in separate units, the aqueous mixture 138, the CE 100, and the solvent 102 are combined in a common unit to form an initial emulsion.

[0187] In one embodiment or in combination with any embodiment mentioned herein, the aqueous mixture 138, the CE 100, and the solvent 102 are agitated in unit 182, and the combined CE coating and aqueous mixture is circulated through a high shear mixer to disperse the solid phase within the liquid phase of the initial emulsion and to promote solid phase hardening to produce the initial microparticles.

[0188] To produce the initial microparticles, the combined aqueous mixture 138, the CE 100, and the solvent 102 are agitated at unit 182. The agitation performed at unit 182 can be quantified by at least one of: (1) an impeller tip speed, (2) an impeller Reynolds number, and (3) a power mass ratio. In one embodiment or in combination with any embodiment mentioned herein, the high shear mixing is performed at an impeller tip speed of at least 25, 50, 75, 100, 150, 200, 250, or 300 cm / s, and / or no more than 1000, 500, 400, 300, 200, or 100 cm / s. In one embodiment or in combination with any embodiment mentioned herein, the high shear mixing is performed at an impeller Reynolds number of at least 500, 1000, 1500, 2000, 3000, 4000, 5000, or 6000, and / or no more than 15000, 10000, 8000, 6000, 5000, 4000, or 3000. In one embodiment or in combination with any embodiment mentioned herein, the high shear mixing is performed at a power mass ratio of at least 0.01, 0.02, 0.03, 0.1, 0.5, 1.0, 1.5, 2.0, 2.5, or 3.0, and / or no more than 10.0, 7.5, 5.0, 4.0, 3.0, 2.5, 2.0, 1.5, 1.0, 0.5, or 0.1.

[0189] The pre-hardened dispersion 150 is then discharged from unit 182 and the hardened CE microparticles 112 are recovered therefrom as described above.

[0190] Reference is made to Figure 4 The CE microparticles 112 are produced by separate coating and aqueous mixture formation and combined emulsion / dispersion formation and particle hardening. In example embodiments, the particle formation is as described in U.S. Patent No. 9, 1 1 1, 1 10, which is incorporated by reference herein in its entirety. Figure 2Formation is initiated in the middle, where CE coating 136 and aqueous mixture 138 are formed in separate units.

[0191] However, in Figure 4 In the middle, CE coating 136 and aqueous mixture 138 are fed into a common emulsion / dispersion formation and particle hardening unit 184. At unit 184, CE coating 136 and aqueous mixture 138 are combined and agitated to form an initial emulsion as described herein. Once the initial emulsion is formed, extractant 154 is fed directly into unit 184 to desolvate the initial microparticles.

[0192] Referring to Figure 5 , CE microparticles 112 are produced by combined emulsion / dispersion formation. In an example embodiment, particle formation is initiated by combining CE 100, solvent 102, water 104, hydrocolloid 106, surfactant 108, and optionally recycled solvent 146 and recycled water 178 all in a common unit 186. This mixture is agitated as described herein to produce a pre-hardened dispersion 150 containing initial microparticles. The pre-hardened dispersion is received at unit 152 to desolvate the initial microparticles as described herein.

[0193] Referring to Figure 6 , CE microparticles 112 are produced by combined emulsion / dispersion formation and particle hardening. In an example embodiment, particle formation is initiated by combining CE 100, solvent 102, water 104, hydrocolloid 106, surfactant 108, and optionally recycled solvent 146 and recycled water 178 all in a common unit 188. At unit 188, these components are combined and agitated to form an initial emulsion as described herein. Once the initial emulsion is formed, extractant 154 is fed directly into unit 188 to desolvate the initial microparticles.

[0194] Referring to Figure 7 , CE microparticles 112 are produced by solvent flashing prior to particle hardening. In an example embodiment, pre-hardened dispersion 150 discharged from unit 144 is received at a flashing unit 190 instead of being received at particle hardening unit 152. At unit 144, at least some of the solvent of pre-hardened dispersion 150 is removed from its liquid phase, thereby forming a solvent-depleted dispersion 192 having a reduced solvent content. Solvent-depleted dispersion 192 is received at unit 152 to harden the pre-hardened microparticles contained therein as described above. Flashed solvent stream 194 discharged from unit 190 can be directed to unit 176 for liquid processing and recycling thereof.

[0195] In an embodiment or in combination with any of the embodiments mentioned herein, removal at unit 144 is by pervaporation, cross-flow membrane filtration (ultrafiltration or nanofiltration), flash tank, spray tank, or wiped film evaporation.

[0196] In an embodiment or in combination with any of the embodiments mentioned herein, removal at unit 144 reduces the solvent in the dispersion by at least 30 wt%, at least 50 wt%, at least 75 wt%, at least 90 wt%, between 30 wt% and 90 wt%, or between 50 wt% and 75 wt%.

[0197] In an embodiment or in combination with any of the embodiments mentioned herein, the solvent-depleted dispersion 192 has a solids content of at least 3 wt%, 4 wt%, 5 wt%, or 6 wt%, and / or no more than 40 wt%, 30 wt%, 20 wt%, or 10 wt%.

[0198] In an embodiment or in combination with any of the embodiments mentioned herein, the volume ratio of the submerging liquid used in unit 152 to the dispersion is less than 2.5: 1, 2: 1, 1.75: 1, 1.5: 1, 1.25: 1, or 1: 1.

[0199] Hardened CE microparticles

[0200] Hardened CE microparticles produced by the methods disclosed herein exhibit desirable tactile and / or optical qualities, for example, tactile and / or optical qualities that make them suitable for use in personal care products, cosmetics, and the like. As used herein, the term “beads,” “microparticles,” or “CE microparticles” can be used interchangeably with the term “hardened CE microparticles,” but it is understood that “hardened CE microparticles” are made via a wet solvent / emulsion method, and that microbeads can also be produced from larger CE form factors via a mechanical milling process (e.g., jet milling) that includes dry milling or size reduction methods (as described herein).

[0201] In an embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles are produced at a rate of at least 50, 100, 250, 500, 1000, 2500, 5000, or 10000 kilograms per day, and / or no more than 100000, 75000, or 50000 kilograms per day. To achieve these production rates, the CE, solvent, and / or water are provided within the system at one or more of the following corresponding rates.

[0202] In an embodiment or in combination with any of the embodiments mentioned herein, the CE is provided at unit 140 at a rate of at least 50, 100, 250, 500, 1000, 2500, 5000, or 10000 kilograms per day, and / or no more than 100000, 75000, or 50000 kilograms per day.

[0203] In an embodiment or in combination with any of the embodiments mentioned herein, the solvent is provided at unit 140 at a rate of at least at least 50, 100, 250, 500, 1000, 2500, 5000, or 10000 kilograms per day, and / or no more than 100000, 75000, or 50000 kilograms per day.

[0204] In an embodiment or in combination with any of the embodiments mentioned herein, the water is provided at unit 152 at a rate of at least at least 500, 1000, 2500, 5000, 10000, 25000, 50000, or 100000 kilograms per day, and / or no more than 1000000, 750000, or 500000 kilograms per day.

[0205] In an embodiment or in combination with any of the embodiments mentioned herein, the hardened CE microparticles have a hardness at 20°C that is greater than the hardness at 20°C of the initial microparticles contained within the pre-hardened dispersion 150 and / or formed in any of the processes described herein.

[0206] In an embodiment or in combination with any of the embodiments mentioned herein, the hardened CE microparticles have a hardness that is at least 1.1, 1.25, 1.5, 1.75, or 2 times the hardness of the initial microparticles.

[0207] In an embodiment or in combination with any of the embodiments mentioned herein, the hardened CE microparticles have a solvent content that is less than 100, 50, 25, or 10 ppm.

[0208] In an embodiment or in combination with any of the embodiments mentioned herein, the hardened CE microparticles have a solvent content that is less than the solvent content of the initial microparticles.

[0209] In an embodiment or in combination with any of the embodiments mentioned herein, the hardened CE microparticles have a solvent content that is less than 0.99, 0.95, 0.9, 0.8, 0.7, 0.6, or 0.5 of the solvent content of the initial microparticles.

[0210] In an embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have a D50 volume-based particle size that is within 50%, 25%, 15%, 10%, 5%, or 2% of the D50 particle size of the initial microparticles.

[0211] In an embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have a D50 volume-based particle size that is less than 0.99, 0.95, 0.9, 0.8, 0.7, 0.6, or 0.5 of the D50 volume-based particle size of the initial microparticles.

[0212] In an embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have a D50 volume-based particle size in the range of 1 to 100, 1 to 80, 1 to 70, 1 to 60, 1 to 50, 1 to 40, 1 to 35, 1 to 30, 1 to 25, 1 to 20, 1 to 15, 1 to 10, 2 to 100, 2 to 80, 2 to 70, 2 to 60, 2 to 50, 2 to 40, 2 to 35, 2 to 30, 2 to 25, 2 to 20, 2 to 15, 2 to 10, 3 to 100, 3 to 80, 3 to 70, 3 to 60, 3 to 50, 3 to 40, 3 to 35, 3 to 30, 3 to 25, 3 to 20, 3 to 15, 3 to 10, 5 to 100, 5 to 80, 5 to 70, 5 to 60, 5 to 50, 5 to 40, 5 to 35, 5 to 30, 5 to 25, 5 to 20, 5 to 15, 5 to 10, 10 to 100, 10 to 80, 10 to 70, 10 to 60, 10 to 50, 10 to 40, 10 to 35, 10 to 30, 10 to 25, 10 to 20, 10 to 15, 15 to 100, 15 to 80, 15 to 70, 15 to 60, 15 to 50, 15 to 40, 15 to 35, 15 to 30, 15 to 25, 15 to 20, 20 to 100, 20 to 80, 20 to 70, 20 to 60, 20 to 50, 20 to 40, 20 to 35, 20 to 30, 25 to 100, 25 to 80, 25 to 70, 25 to 60, 25 to 50, 25 to 40, 25 to 35, 25 to 30, 30 to 100, 30 to 80, 30 to 70, 30 to 60, 30 to 50, 30 to 40, or 30 to 35 microns. For example, the CE microparticles can have a D50 volume-based particle size of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100 microns.

[0213] As used herein, the term“D50 volume-based” means that 50% of the beads / particles by volume have a maximum dimension less than or equal to the value noted (e.g., 10 microns). This D50 value can also be considered a median particle size. To ensure that a representative D50 value is obtained, the sample size of beads / particles should be at least 0.5 grams. The sample size of particles is then dispersed and mixed in 1.5 ounces of isopropyl alcohol. The testing of D50 is performed by laser diffraction and computer algorithms using the Mie theory for generating particle size distributions. One suitable particle size analyzer for determining D50 values is the Malvern Mastersizer 3000 from Malvern Panalytical. When using the Malvern Mastersizer, the obscuration rate can be set between 2% and 5%, and the sample measurement time for both red and blue light measurements is set to three seconds. The dispersed sample is added until the desired obscuration rate is reached (about 4%), and then the measurement is taken. After the first measurement, the sample is sonicated at 50% power for 120 seconds. Subsequently, after sonication, the dispersed sample is measured again once the light energy has stabilized (typically less than one minute).

[0214] In one embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have a D10 volume-based particle size of 0.5 to 20, 0.5 to 15, 0.5 to 12, 0.5 to 10, 0.5 to 5, 0.5 to 4, 0.5 to 3, 0.5 to 2, 0.5 to 1, 1 to 20, 1 to 15, 1 to 12, 1 to 5, 1 to 3, 2 to 20, 2 to 10, 2 to 5, 3 to 20, 3 to 15, 3 to 10, 4 to 20, 4 to 15, 4 to 10, 5 to 20, 5 to 15, 5 to 10, 10 to 20, or 10 to 15 microns. For example, the CE microparticles can have a D10 volume-based particle size of 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 microns.

[0215] As used herein, the term“based on D10 volume” means that 10% of the beads / particles have a maximum dimension less than or equal to the noted value (e.g., 10 microns) on a volume basis. To ensure that a representative D10 value is obtained, the sample size of the beads / particles should be at least 0.5 grams. The particle sample size is then dispersed and mixed in 1.5 ounce isopropyl alcohol. The D10 is tested by laser diffraction and computer algorithm using the Mie theory for generating particle size distributions. One suitable particle size analyzer for determining D10 values is the Malvern Mastersizer 3000 from Malvern Panalytical. When using the Malvern Mastersizer, the obscuration rate can be set between 2% and 5%, and the sample measurement time for both red and blue light measurements is set to three seconds. The dispersed sample is added until the desired obscuration rate is reached (about 4%), and then the measurement is taken. After the first measurement, the sample is sonicated at 50% power for 120 seconds. Subsequently, after sonication, the dispersed sample is measured again once the light energy has stabilized (typically less than one minute).

[0216] In one embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have a particle size based on D90 volume in the range of 1 to 100, 1 to 80, 1 to 70, 1 to 60, 1 to 50, 1 to 40, 1 to 35, 1 to 30, 1 to 25, 1 to 20, 1 to 15, 1 to 10, 5 to 100, 5 to 80, 5 to 70, 5 to 60, 5 to 50, 5 to 40, 5 to 35, 5 to 30, 5 to 25, 5 to 20, 5 to 15, 5 to 10, 10 to 100, 10 to 80, 10 to 70, 10 to 60, 10 to 50, 10 to 40, 10 to 35, 10 to 30, 10 to 25, 10 to 20, 10 to 15, 15 to 100, 15 to 80, 15 to 70, 15 to 60, 15 to 50, 15 to 40, 15 to 35, 15 to 30, 15 to 25, 15 to 20, 20 to 100, 20 to 80, 20 to 70, 20 to 60, 20 to 50, 20 to 40, 20 to 35, 20 to 30, 25 to 100, 25 to 80, 25 to 70, 25 to 60, 25 to 50, 25 to 40, 25 to 35, 25 to 30, 30 to 100, 30 to 80, 30 to 70, 30 to 60, 30 to 50, 30 to 40, or 30 to 35 microns. For example, the CE microparticles can have a particle size based on D90 volume of 100, 90, 80, 70, 60, 50, 49, 48, 47, 46, 45, 44, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, or 20 microns.

[0217] As used herein, the term "based on D90 volume" means that, based on volume, 90% of the beads / particles have a maximum dimension that is less than or equal to the noted value (e.g., 10 microns). To ensure that a representative D90 value is obtained, the sample size of the beads / particles should be at least 0.5 grams. The particle sample size is then dispersed and mixed in 1.5 ounces of isopropyl alcohol. The test for D90 is performed by laser diffraction and computer algorithm using the Mie theory for generating particle size distributions. One suitable particle size analyzer for determining D90 values is the Malvern Mastersizer 3000 from Malvern Panalytical. When using the Malvern Mastersizer, the obscuration rate can be set between 2% and 5%, and the sample measurement time for both red and blue light measurements is set to three seconds. The dispersed sample is added until the desired obscuration rate is reached (about 4%), and then the measurement is taken. After the first measurement, the sample is sonicated at 50% power for 120 seconds. Subsequently, the dispersed sample is measured again after sonication once the light energy has stabilized (typically less than one minute).

[0218] In one embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have a D100 volume-based particle size in the range of 1 to 100, 1 to 80, 1 to 70, 1 to 60, 1 to 50, 1 to 40, 1 to 35, 1 to 30, 1 to 25, 1 to 20, 1 to 15, 1 to 10, 5 to 100, 5 to 80, 5 to 70, 5 to 60, 5 to 50, 5 to 40, 5 to 35, 5 to 30, 5 to 25, 5 to 20, 5 to 15, 5 to 10, 10 to 100, 10 to 80, 10 to 70, 10 to 60, 10 to 50, 10 to 40, 10 to 35, 10 to 30, 10 to 25, 10 to 20, 10 to 15, 15 to 100, 15 to 80, 15 to 70, 15 to 60, 15 to 50, 15 to 40, 15 to 35, 15 to 30, 15 to 25, 15 to 20, 20 to 100, 20 to 80, 20 to 70, 20 to 60, 20 to 50, 20 to 40, 20 to 35, 20 to 30, 25 to 100, 25 to 80, 25 to 70, 25 to 60, 25 to 50, 25 to 40, 25 to 35, 25 to 30, 30 to 100, 30 to 80, 30 to 70, 30 to 60, 30 to 50, 30 to 40, or 30 to 35 microns. For example, the CE microparticles can have a D100 volume-based particle size of 100, 90, 80, 70, 60, 50, 49, 48, 47, 46, 45, 44, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, or 20 microns.

[0219] As used herein, the term "based on D100 volume" means that, on a volume basis, 100% of the beads / particles have a maximum dimension less than or equal to the value noted (e.g., 10 microns). To ensure that a representative D100 value is obtained, the sample size of the beads / particles should be at least 0.5 grams. The particle sample size is then dispersed and mixed in 1.5 ounces of isopropyl alcohol. The testing of D100 is done by laser diffraction and computer algorithms using the Mie theory for generating particle size distributions. One suitable particle size analyzer for determining D100 values is the Malvern Mastersizer 3000 from Malvern Panalytical. When using the Malvern Mastersizer, the obscuration rate can be set between 2% and 5%, and the sample measurement time for both red and blue light measurements is set to three seconds. The dispersed sample is added until the desired obscuration rate is reached (about 4%), and then the measurement is taken. After the first measurement, the sample is sonicated at 50% power for 120 seconds. Subsequently, after sonication, the dispersed sample is measured again once the light energy has stabilized (typically less than a minute).

[0220] In one embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have a D[4,3] mean particle size in the range of 1 to 100, 1 to 80, 1 to 70, 1 to 60, 1 to 50, 1 to 40, 1 to 35, 1 to 30, 1 to 25, 1 to 20, 1 to 15, 1 to 10, 1 to 8, 1 to 6, 1 to 5, 2 to 40, 2 to 35, 2 to 30, 2 to 25, 2 to 20, 2 to 15, 2 to 10, 2 to 8, 2 to 6, 2 to 5, 3 to 40, 3 to 35, 3 to 30, 3 to 25, 3 to 20, 3 to 15, 3 to 10, 3 to 8, 3 to 6, 3 to 5, 4 to 40, 4 to 35, 4 to 30, 4 to 25, 4 to 20, 4 to 15, 4 to 10, 4 to 8, 4 to 6, 5 to 100, 5 to 80, 5 to 70, 5 to 60, 5 to 50, 5 to 40, 5 to 35, 5 to 30, 5 to 25, 5 to 20, 5 to 15, 5 to 10, 10 to 100, 10 to 80, 10 to 70, 10 to 60, 10 to 50, 10 to 40, 10 to 35, 10 to 30, 10 to 25, 10 to 20, 10 to 15, 15 to 100, 15 to 80, 15 to 70, 15 to 60, 15 to 50, 15 to 40, 15 to 35, 15 to 30, 15 to 25, 15 to 20, 20 to 100, 20 to 80, 20 to 70, 20 to 60, 20 to 50, 20 to 40, 20 to 35, 20 to 30, 25 to 100, 25 to 80, 25 to 70, 25 to 60, 25 to 50, 25 to 40, 25 to 35, 25 to 30, 30 to 100, 30 to 80, 30 to 70, 30 to 60, 30 to 50, 30 to 40, or 30 to 35 microns. For example, the CE microparticles can have a D100 volume-based particle size of 100, 90, 80, 70, 60, 50, 49, 48, 47, 46, 45, 44, 43, 42, 41, 40, 39, 38, 37, 36, 35, 34, 33, 32, 31, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, or 20 microns.

[0221] As used herein, the term "D[4,3] average particle size" means the D[4,3] average as described in ASTM E 799, and also known as the De Brouckere average, which is the sum of the fourth power of the individual diameters multiplied by the percentage, divided by the same calculation for the third power. To ensure that a representative D[4,3] value is obtained, the sample size of the beads / particles should be at least 0.5 grams. The particle sample size is then dispersed and mixed in 1.5 ounces of isopropyl alcohol. One suitable particle size analyzer for determining D100 values is the Malvern Mastersizer 3000 from Malvern Panalytical. When using the Malvern Mastersizer, the obscuration rate can be set between 2% and 5%, and the sample measurement time for both red and blue light measurements are set to three seconds. The dispersed sample is added until the desired obscuration rate is reached (about 4%), and then the measurement is taken. After the first measurement, the sample is sonicated at 50% power for 120 seconds. Subsequently, after sonication, the dispersed sample is measured again once the light energy has stabilized (typically less than one minute).

[0222] In one embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have an average sphericity of at least at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95%, 95%, 97%, 98%, or 99%. Additionally or in the alternative, the CE microparticles can have an average sphericity of no more than 99%, 95%, 90%, 80%, 70%, 60%, 50%, 40%, or 30%. In certain embodiments, the CE microparticles have an average sphericity in the range of 5% to 60%, or 5% to 50%, or 5% to 40%, or 5% to 30%, or 5% to 25%, or 5% to 20%, or 10% to 60%, or 10% to 50%, or 10% to 40%, or 10% to 30%, or 10% to 25%, or 10% to 20%. In embodiments, the CE microparticles are produced via a mechanical size reduction method (as described herein), such as jet milling, and have an average sphericity in the range of 5% to 40%, or 5% to 30%, or 5% to 25%, or 5% to 20%, or 10% to 40%, or 10% to 30%, or 10% to 25%, or 10% to 20%.

[0223] In certain embodiments, the CE microparticles have an average sphericity in the range of 70% to 100%, or 70% to 90%, or 70% to 80%, or 75% to 100%, or 75% to 90%, or 75% to 80%, or 80% to 100%, or 80% to 90%. In embodiments, the CE microparticles are produced via a solvent or emulsion method (as described herein) and have an average sphericity in the range of 70% to 100%, or 70% to 90%, or 70% to 80%.

[0224] The average sphericity is determined by (1) acquiring a secondary emission / ETD detector scanning electron microscopy (SEM) image of a representative sample of at least 40 microparticles, (2) on the SEM image, selecting a square sample window centered on the SEM center that contains exactly 30 microparticles with their entire outer perimeters clearly visible (i.e., not obscured), (3) measuring the maximum and minimum diameters of the 30 clearly visible microparticles in the sample window (each diameter extends through the centroid of the particle and is not necessarily perpendicular to the other), (4) for each of the 30 particles, dividing the minimum diameter by the maximum diameter and multiplying the result by 100% to obtain 30 individual particle sphericities, and (5) averaging the 30 individual particle sphericities to obtain the average sphericity. As used herein, the term “spherical” with respect to describing the shape of a CE microparticle means that the CE microparticle has an average sphericity of at least 70%. As used herein, the term “spheroidal” with respect to describing the shape of a CE microparticle means that the CE microparticle has an average sphericity of less than 70%.

[0225] In one embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles exhibit a monomodal particle size distribution with a span of at least 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, 0.95, 1.0, 1.05, 1.1, 1.15, 1.2, 1.25, 1.3, or 1.4, and / or less than 3.0, 2.9, 2.8, 2.7, 2.6, 2.5, 2.4, 2.3, 2.2, 2.1, 2.0, 1.9, 1.8, 1.7, 1.6, or 1.5. In certain embodiments, the CE microparticles exhibit a monomodal particle size distribution with a span of 1.0 to 3.0, 1.0 to 2.5, 1.0 to 2.0, 1.0 to 1.8, 1.0 to 1.6, 1.2 to 3.0, 1.2 to 2.5, 1.2 to 2.0, 1.2 to 1.8, 1.2 to 1.6, 1.3 to 3.0, 1.3 to 2.5, 1.3 to 2.0, 1.3 to 1.8, or 1.3 to 1.6. As used herein, a “monomodal particle size distribution” refers to a particle size distribution of a material having only a single significant peak of the size distribution. This is in contrast to a multimodal particle size distribution, which has two or more peaks of the particle size distribution. The “span” of a monomodal peak can be measured using the D10, D50, and D90 values of the particles using the following equation:

[0226] (D x (90)-D x (10)) / D x (50),

[0227] where “x” is the specified particle size.

[0228] In one embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have an average smoothness of at least 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95%, 95%, 97%, 98%, or 99%. Additionally or in the alternative, the CE microparticles can have an average smoothness of no more than 99%, 95%, 90%, 80%, 70%, 60%, 50%, 40%, or 30%.

[0229] The average smoothness is determined by: (1) acquiring a secondary emission / EDT detector scanning electron microscopy (SEM) image of a representative sample of at least 20 particles, (2) on the SEM, selecting a square sample window centered on the SEM center that contains exactly 10 particles with their entire outer perimeter clearly visible (i.e., not obscured), (3) binarizing the sample window by hand binarization, selecting upper and lower threshold values to match the precise shape of the darker regions of the particles, (4) for each of the 10 particles, selecting a square window at or near the center of the particle that is approximately 1 / 3 the length and width of the particle diameter (prior to binarizing the particle), (5) dividing the area of the dark regions in the square window by the total area of the square window and multiplying the result by 100% to obtain 10 individual particle smoothness values, and (5) averaging the 10 individual particle smoothness values to obtain the average smoothness.

[0230] In one embodiment or in combination with any of the embodiments mentioned herein, the CE particles have an average BET surface area of at least 0.1, 0.5, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0, 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9, 5.0, 5.1, 5.2, 5.3, 5.4, 5.5, 5.6, 5.7, 5.8, 5.9, 6.0, 6.1, 6.2, 6.3, 6.4, 6.5, 6.7, 6.8, 6.9, 7.0, 7.1, 7.2, 7.3, 7.4, 7.5, 7.6, 7.7, 7.8, 7.9, or 8.0 m2 / g, and / or no more than 100, 95, 90, 85, 80, 75, 70, 65, 60, 55, 50, 45, 40, 35, 30, 29, 28, 27, 26, 25, 24, 23, 22, 21, 20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2.5, 2, 1.9, 1.8, 1.7, 1.6, 1.5, 1.4, or 1.3 m2 / g, measured according to ISO 9277 using a Micromeritics ASAP 2020 instrument and krypton.

[0231] In an embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have a BET average pore size of at least 25, 30, 35, 40, 45, 50, 55, 56, 57, 58, or 59 angstroms, and / or less than 75, 70, 65, or 60 angstroms, measured according to ISO 9277 and ISO 15901-02 using a Micromeritics ASAP 2020 instrument and nitrogen.

[0232] In an embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have a BJH average pore size of at least 50, 60, 70, 80, 90, 100, 110, 120, 125, or 130 angstroms, and / or less than 200, 190, 180, 170, 160, 150, 140, or 130 angstroms, measured according to ISO 15901-02 using a Micromeritics ASAP 2020 instrument and nitrogen.

[0233] In an embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have a BJH surface area of pores from 17 to 3,000 angstroms of at least 0.5, 1.0, 1.1, 1.2, 1.3, 1.4, or 1.5, and / or less than 2.5, 2.0, 1.9, 1.8, 1.7, 1.6, 1.5, 1.4, or 1.3 m2 / g, measured according to ISO 15901-02 using a Micromeritics ASAP 2020 instrument and nitrogen. 2 In an embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have a BJH surface area of pores from 17 to 3,000 angstroms of at least 0.5, 1.0, 1.1, 1.2, 1.3, 1.4, or 1.5, and / or less than 2.5, 2.0, 1.9, 1.8, 1.7, 1.6, 1.5, 1.4, or 1.3 m2 / g, measured according to ISO 15901-02 using a Micromeritics ASAP 2020 instrument and nitrogen.

[0234] In an embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have a BJH volume of pores from 17 to 3,000 angstroms of at least 0.001, 0.002, 0.003, or 0.004, and / or less than 0.1, 0.05, or 0.01 mL / g, measured according to ISO 15901-02 using a Micromeritics ASAP 2020 instrument and nitrogen.

[0235] In an embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have a true specific gravity of at least 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9, and / or not more than 1.5, 1.4, 1.3, 1.2, 1.1, 1.0, 0.9, 0.8, 0.7, or 0.6, measured by JIS Z 8807-1976.

[0236] In an embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have a bulk specific gravity of at least 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, or 0.8, and / or not more than 1.4, 1.3, 1.2, 1.1, 1.0, 0.9, 0.8, 0.7, 0.6, or 0.5, as measured by JIS 1201-1.

[0237] In an embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have a polydispersity index of less than 0.8, 0.7, 0.6, 0.5, 0.4, or 0.3.

[0238] In an embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have a surfactant content of less than 200, 150, 100, 50, 20, 10, 7.5, 5, 2.5, or 1 ppmw.

[0239] In an embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have a plasticizer content of less than 200, 150, 100, 50, 20, 10, 7.5, 5, 2.5, or 1 ppmw.

[0240] In an embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have a butyric acid content of less than 500, 400, 300, 200, 100, 50, 20, 10, 7.5, 5, 2.5, or 1 ppmw.

[0241] In an embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have an acetic acid content of less than 500, 400, 300, 200, 100, 50, 20, 10, 7.5, 5, 2.5, or 1 ppmw.

[0242] In an embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have a propionic acid content of less than 500, 400, 300, 200, 100, 50, 20, 10, 7.5, 5, 2.5, or 1 ppmw.

[0243] The butyric acid, acetic acid, and propionic acid content of the CE microparticles can be measured by gas chromatography ("GC"). Under one GC method, the butyric acid, acetic acid, and propionic acid content can be measured by adding about 100 mg of CE microparticles to a tared 4 dram vial, followed by the addition of an internal standard solution comprising nonane in a 90:10 mixture of dichloromethane / methanol. A magnetic stir bar is placed in the vial, and the sample is stirred for two hours. After stirring, 8.0 mL of n-heptane is added dropwise to precipitate the polymer, and the sample is then vortexed. Approximately 100 mg of the supernatant is transferred to a GC vial with 100 μΐ^of pyridine and 450 μΐ^of BSTFA. The sample is heated at 80 °C for 30 minutes, and then cooled to room temperature prior to injection. The sample is chromatographed using programmed temperature and flame ionization detection simultaneously on a 100% dimethylpolysiloxane and 14% cyanopropyl-phenyl-methylpolysiloxane column. Alternatively, a second GC method involves preparing the sample by adding about 30 mg of CE microparticles to a tared GC vial, followed by the addition of 200 μΐ^of an internal standard solution comprising decane in pyridine and 1.0 mL of BSTFA. The vial is heated at 80 °C for 30 minutes, and then cooled to room temperature prior to injection. The sample is then chromatographed using programmed temperature and flame ionization detection simultaneously on a 100% dimethylpolysiloxane and 6% cyanopropyl-phenyl-methylpolysiloxane column.

[0244] In one embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have a sulfuric acid content of less than 500, 400, 300, 200, 100, 50, 20, 10, 7.5, 5, 2.5, or 1 ppmw. The sulfuric acid content of the CE microparticles can be measured by the following method. First, the sample being tested is added to a titration cell and dissolved in solvent to a total volume of 70 mL. A solvent blank is also prepared for comparison. The sample and blank are then titrated with 0.05 N potassium hydroxide in methanol using an automatic titrator equipped with a combination glass potentiometric electrode. The acid value is calculated based on the sample weight and KOH consumed in the sample minus KOH consumed in the blank.

[0245] In an embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles have a CE content of mixed cellulose esters of the first aspect, the second aspect, and / or the third aspect (including any category or subcategory of these aspects) of at least 50 wt.%, 55 wt.%, 60 wt.%, 65 wt.%, 70 wt.%, 75 wt.%, 80 wt.%, 85 wt.%, 90 wt.%, 91 wt.%, 92 wt.%, 93 wt.%, 94 wt.%, 95 wt.%, 96 wt.%, 97 wt.%, 98 wt.%, or 99 wt.%. Additionally, or in the alternative, the CE microparticles can have a CE content of mixed cellulose esters of the first aspect, the second aspect, and / or the third aspect (including any category or subcategory of these aspects) of less than 99.9 wt.%, 99.5 wt.%, 99 wt.%, 98 wt.%, 97 wt.%, 96 wt.%, 95 wt.%, 94 wt.%, 93 wt.%, 92 wt.%, 91 wt.%, 90 wt.%, 89 wt.%, 88 wt.%, 87 wt.%, 86 wt.%, or 85 wt.%. In certain embodiments, the CE microparticles can consist essentially of mixed cellulose esters of the first aspect, the second aspect, and / or the third aspect (including any category or subcategory of these aspects).

[0246] In an embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles can contain additional biodegradable cellulose esters that are different from the mixed cellulose esters of the first aspect, the second aspect, and / or the third aspect. In such embodiments, this additional cellulose ester can be cellulose acetate that exhibits at least 40% biodegradability, at least 45% biodegradability, or at least 50% biodegradability, or at least 55% biodegradability, at least 60% biodegradability, or at least 65% biodegradability, or at least 70% biodegradability, or at least 75% biodegradability, or at least 80% biodegradability, or at least 85% biodegradability at 60 days according to at least one of the OECD 301B, OECD 301C, or OECD 301F test methods.

[0247] In an embodiment or in combination with any of the embodiments mentioned herein, the CE microparticles can contain at least 1 wt.%, 2 wt.%, 3 wt.%, 4 wt.%, 5 wt.%, 6 wt.%, 7 wt.%, 8 wt.%, 9 wt.%, or 10 wt.% of additional biodegradable cellulose esters that are different from the mixed cellulose esters of the first aspect, the second aspect, and / or the third aspect. Additionally, or in the alternative, the CE microparticles can contain less than 50 wt.%, 45 wt.%, 40 wt.%, 35 wt.%, 30 wt.%, 25 wt.%, 20 wt.%, 15 wt.%, 10 wt.%, or 5 wt.% of additional biodegradable cellulose esters that are different from the mixed cellulose esters of the first aspect, the second aspect, and / or the third aspect.

[0248] In an embodiment or in combination with any other embodiment mentioned herein, the CE microparticles have a moisture content of one or more of the following amounts: (1) greater than 0 wt.%; (2) no more than 10 wt.%, 9 wt.%, 8 wt.%, 7 wt.%, 6 wt.%, 5 wt.%, 4 wt.%, 3 wt.%, 2 wt.%, 1 wt.%, or 0.05 wt.%; and (3) in a range of 0-10 wt.%, 0-5 wt.%, 0-4 wt.%, 0-3 wt.%, or 1.3 wt.%.

[0249] In an embodiment or in combination with any other embodiment mentioned herein, the CE microparticles exhibit biodegradability of at least 40%, biodegradability of at least 45%, or biodegradability of at least 50%, or biodegradability of at least 55%, biodegradability of at least 60%, or biodegradability of at least 65%, or biodegradability of at least 70%, or biodegradability of at least 75%, or biodegradability of at least 80%, or biodegradability of at least 85% at 56 days according to at least one of the OECD 301B, OECD 301C, or OECD 301F test methods.

[0250] In an embodiment or in combination with any other embodiment mentioned herein, the CE microparticles exhibit biodegradability of at least 40%, biodegradability of at least 45%, or biodegradability of at least 50%, or biodegradability of at least 55%, biodegradability of at least 60%, or biodegradability of at least 65%, or biodegradability of at least 70%, or biodegradability of at least 75%, or biodegradability of at least 80%, or biodegradability of at least 85% at 60 days according to at least one of the OECD 301B, OECD 301C, or OECD 301F test methods.

[0251] In an embodiment or in combination with any other embodiment mentioned herein, the CE microparticles exhibit an oil uptake of at least 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100 mL / 100 g (or alternatively, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, or 100 g oil / 100 g microparticles) measured using test method ASTM D281, wherein mineral oil is used in place of castor oil.

[0252] In an embodiment or in combination with any other embodiment mentioned herein, the CE microparticles exhibit a zeta potential of at least -95, at least -90, at least -85, at least -80, at least -75, at least -70, at least -65, at least -60, at least -55, at least -50, or at least -45 mV. Additionally, or in the alternative, the CE microparticles can exhibit a zeta potential of less than -5, less than -10, less than -15, less than -20, less than -25, less than -30, less than -35, less than -40, less than -45, less than -50, less than -55, less than -60, or less than -65 mV.

[0253] The zeta potential was measured by dispersing the microparticles in water for 30 seconds via vortex mixing. The microparticle concentration was controlled at 0.5 mg / ml. The zeta potential test was performed on a Zetasizer Nano Series ZEN 3600 instrument from Malvern Panalytical, equipped with a DTS1070 sample cell. The zeta potential calculation was then performed using the Smoluchowski model.

[0254] In an embodiment or in combination with any other embodiment mentioned herein, the CE microparticles exhibit a haze transmittance of at least 20%, at least 25%, at least 30%, at least 35%, at least 40%, or at least 45%. Additionally, or in the alternative, the CE microparticles can exhibit a haze transmittance of less than 90%, less than 85%, less than 80%, less than 75%, less than 70%, less than 65%, less than 60%, less than 55%, less than 50%, less than 45%, less than 40%. The haze transmittance can be measured using a BYK Glossmeter and a BYK Haze Gard I by forming an aqueous emulsion comprising 5 wt% of the biodegradable beads / microparticles.

[0255] The detailed procedure for measuring haze is as follows. The W / O emulsion used to measure the % haze was prepared using the following procedure. The emulsion was prepared using two phases. Phase A was made from water, magnesium sulfate heptahydrate (Merck), and Euxyl PE9010 (Ashland) at the following weight concentrations, respectively, 59:2:1. Phase B was made from caprylic / capric triglyceride (Making Cosmetics), C1215 alkyl benzoate (Making Cosmetics), Emullium Illustro (Gattefosse), bentone Gel ISD V (Elementis), and microparticulate powder at the following weight concentrations, respectively, 12.5:12.5:5:3:5. Phase A was prepared by mixing the listed components. Phase B was prepared by top stirring in the absence of microparticulate powder until all components were dissolved. Phase A was then added to Phase B while stirring at 1000 rpm until fully mixed. The microparticulate powder was then added to the mixture while mixing at 1000 rpm for 5 minutes. The resulting mixture was homogenized with an Ultra Turax at 10,000 rpm for 5 minutes. The haze transmittance of a draw down film (38 um) after 5 min drying at 50 °C was measured using a BYK Haze Gard I.

[0256] In one embodiment or in combination with any other embodiment mentioned herein, the CE microparticles exhibit a total transmittance of at least 50%, at least 60%, at least 70%, at least 75%, at least 80%, at least 85%, at least 86%, at least 87%, at least 88%, or at least 89% measured using the procedure disclosed herein using a BYK Haze-Gard I unit.

[0257] Cosmetic Formulation

[0258] The hardened CE microparticles produced by the methods disclosed herein (e.g., the emulsion method) or the CE microparticles produced by the physical size reduction method (e.g., jet milling) can be used to produce a variety of cosmetic compositions. The cosmetic composition can be produced by: (1) providing a plurality of CE microparticles; (2) combining the CE beads / microparticles with one or more cosmetic additives, thereby forming a cosmetic precursor mixture; and (3) forming a cosmetic composition from the cosmetic precursor mixture.

[0259] In an embodiment, or in combination with any other embodiment mentioned herein, the cosmetic composition can include at least 0.1 wt.%, 0.5 wt.%, 1 wt.%, 2 wt.%, 3 wt.%, 4 wt.%, 5 wt.%, 6 wt.%, 7 wt.%, 8 wt.%, 9 wt.%, 10 wt.%, 11 wt.%, 12 wt.%, 13 wt.%, 14 wt.%, or 15 wt.% of the CE microparticles. Additionally, or in the alternative, the cosmetic composition can include less than 99 wt.%, 90 wt.%, 80 wt.%, 70 wt.%, 60 wt.%, 50 wt.%, 40 wt.%, 30 wt.%, 25 wt.%, 20 wt.%, 15 wt.%, 10 wt.%, or 5 wt.% of the CE microparticles. For example, the cosmetic composition can include 0.1 wt.% to 90 wt.%, 0.1 wt.% to 50 wt.%, 0.1 wt.% to 30 wt.%, 0.1 wt.% to 20 wt.%, 0.1 wt.% to 15 wt.%, 0.1 wt.% to 10 wt.%, 0.1 wt.% to 5 wt.%, 1 wt.% to 90 wt.%, 1 wt.% to 50 wt.%, 1 wt.% to 30 wt.%, 1 wt.% to 20 wt.%, 1 wt.% to 15 wt.%, 1 wt.% to 10 wt.%, or 1 wt.% to 5 wt.% of the CE microparticles.

[0260] In an embodiment, or in combination with any other embodiment mentioned herein, the cosmetic composition can be a foundation, a sunscreen, a lipstick, a mascara, an eye shadow, a lotion, a dry shampoo, a liquid shampoo, a body wash, a cream, a hair conditioner, a skin moisturizer, a facial cleanser, a tablet, a foot powder, a baby powder, a shaving cream, or a shaving gel.

[0261] In an embodiment, or in combination with any other embodiment mentioned herein, the cosmetic composition can be a loose powder, a pressed powder, a gel, an emulsion, a liquid, or an aerosol.

[0262] In an embodiment, or in combination with any other embodiment mentioned herein, the cosmetic composition comprises at least 1%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 99% by weight of at least one, two, three, four, or five cosmetic additives. Additionally, or in the alternative, the cosmetic composition can comprise less than 99%, 95%, 90%, 85%, 80%, 75%, 70%, 65%, 60%, 55%, or 50% by weight of at least one, two, three, four, or five cosmetic additives. For example, the cosmetic composition can comprise 1% to 99%, 1% to 95%, 1% to 90%, 1% to 85%, 1% to 80%, 5% to 99%, 5% to 95%, 5% to 90%, 5% to 85%, 10% to 99%, 10% to 95%, 10% to 85%, 10% to 80%, 15% to 99%, 15% to 95%, 15% to 90%, 15% to 85%, or 15% to 80% by weight of at least one, two, three, four, or five cosmetic additives.

[0263] Generally, the cosmetic additives can include solvents, colorants, oils, waxes, fatty acids, alcohols, esters, hydrocarbons, silicone oils, surfactants, metallic soaps, humectants, thickening agents, UV absorbers, antioxidants, oil absorbers, exfoliants, water, or combinations thereof.

[0264] In an embodiment, or in combination with any other embodiment mentioned herein, the colorant includes pigments (e.g., organic pigments and / or inorganic pigments) and / or dyes.

[0265] In an embodiment, or in combination with any other embodiment mentioned herein, the oil includes triglycine, soybean oil, cocoa butter, palm oil, palm kernel oil, hardened oil, and / or hardened castor oil.

[0266] In an embodiment, or in combination with any other embodiment mentioned herein, the wax includes carnauba wax, candelilla wax, lanolin, lanolin, candelilla wax, cotton wax, montan wax, kapok wax, acetylated lanolin, lanolin, and / or lanolin fatty acid isopropyl.

[0267] In an embodiment, or in combination with any other embodiment mentioned herein, the fatty acid comprises lauric acid, myristic acid, palmitic acid, stearic acid, isostearic acid, behenic acid, oleic acid, undecylenic acid, linoleic acid, eicosapentaenoic acid (EPA), and / or docosahexaenoic acid.

[0268] In an embodiment, or in combination with any other embodiment mentioned herein, the alcohol comprises cetyl alcohol, stearyl alcohol, isostearyl alcohol, 2-octyldodecanol, lauryl alcohol, behenyl alcohol, myristyl alcohol, oleyl alcohol, and / or cetearyl alcohol.

[0269] In an embodiment, or in combination with any other embodiment mentioned herein, the ester comprises isopropyl myristate, 2-octyldodecyl myristate, cetyl 2-ethylhexanoate, diisostearyl malate, tripropyleneglycol dineopentanoate, isononyl isononanoate, isotorideyl isononanoate, cetyl octanoate, isocetyl palmitate, butyl stearate, hexyl laurate, myristyl myristate, decyl oleate, dimethyl octanoate hexyl decyl ester, cetyl lactate, myristyl lactate, lanolin acetate, isocetyl stearate, isocetyl isostearate, cholesteryl 12-hydroxystearate, ethylene glycol di-2-ethylhexanoate, fatty acid dipentaerythritol ester, mono isostearate N-alkyl glycol ester, neopentyl glycol dicaprate, glycerol di-2-heptylundecanoate, trimethylpropane tris-2-ethylhexanoate, trimethylpropane tris-hydroxymethylpropane triisostearate, pentaerythritol tetra-2-ethylhexanoate, glycerol tri-2-ethylhexanoate, glycerol trioctanoate, glycerol triisopalmitate, trimethylpropane trihydroxymethylpropane triisostearate, ethylhexyl palmitate, glycerol trimyristate, glycerol tri-2-heptylundecanoate, methyl ricinoleate, oleyl oleate, acetylglycerides, 2-heptylundecyl palmitate, diisobutyl adipate, N-lauroyl-L-glutamic acid hexyldecyl ester, hexyldecyl adipate, diisopropyl sebacate, ethylhexyl succinate, and / or triethyl citrate.

[0270] In an embodiment, or in combination with any other embodiment mentioned herein, the hydrocarbon comprises paraffin, petrolatum, and / or microcrystalline wax.

[0271] In an embodiment, or in combination with any other embodiment mentioned herein, the surfactant comprises an anionic surfactant, a cationic surfactant, and / or a non-ionic surfactant.

[0272] In an embodiment, or in combination with any other embodiment mentioned herein, the thickening agent comprises guar gum, pectin, starch, gelatin, collagen, cellulose derivatives, and / or mannan.

[0273] Examples

[0274] The following examples include the preparation of cellulose esters, the preparation of microparticles, the preparation of cosmetic formulations containing microparticles, and the testing of these compositions.

[0275] Preparation of cellulose ester

[0276] Example 1-1:

[0277] Cellulose acetate butyrate (CAB) was prepared as follows:

[0278] A mixture of cellulose and acid [cellulose (4.3 parts) and acetic acid (AcOH) (11.8 parts)] was added to an agitated reactor and the mixture was heated to 55°C without heating. A few amounts of sulfuric acid were added and the reactor was cooled to 30°C. Subsequently, a mixture of acetic anhydride (Ac2O) (8.9 parts) and butyric anhydride (Bu2O) (5.6 parts) was added and the mixture was cooled to about 9°C under agitation. Additional sulfuric acid was added to a total of 0.6 parts and the resulting reaction mixture was warmed to 50°C until the acylation reaction was complete and the desired molecular weight was obtained. To this reaction mixture was added a mixture of butyric acid (BuOH) (18 parts) and H2O (7.4 parts). The mixture was then stirred at 68°C for 1020 min, but after 80 min a mixture of magnesium acetate (Mg(OAc)2) (0.61 parts), BuOH (6.9 parts), and H2O (2.7 parts) was added. After the entire time period, the mixture was completely neutralized with a solution of Mg(OAc)2(0.86 parts), BuOH (1.5 parts), and H2O (4.8 parts). The mixture was then precipitated in water by conventional methods, washed, and dried to recover the CAB.

[0279] The degree of substitution (DS) and molecular weight (Mw) of the CAB of Example 1-1 was determined. The DS and Mw results are as follows:

[0280] Example 1-1: Cellulose acetate butyrate (DS Ac = 1.87, DS Bu = 0.22, DS OH = 0.91 and M w = 90766)

[0281] General procedure for preparing cellulose esters Examples 1-2 to 1-8

[0282] The cellulose mixture [cellulose and AcOH] ("cellulose mixture") and sulfuric acid, Ac20 and Bu20 ("acylation solution") were cooled to 30 °C in an agitated reactor and the reaction mixture was cooled to about 7 °C with agitation. Additional sulfuric acid was added to the target amount and the resulting reaction mixture was warmed to 45-65 °C with agitation until the acylation reaction was complete and the desired molecular weight was achieved. The reaction mixture was treated with AcOH and BuOH in water ("hydrolysis solution") and stirred at 68 °C under hydrolysis conditions. The reaction mixture was then quenched, neutralized, precipitated, washed, and dried by conventional methods. The relative amounts and reaction conditions for Examples 1-2 to 1-8 are listed in Table 1.1 below.

[0283] Table 1.1

[0284]

[0285] *Blend of 2-4 CAB lots

[0286] Characterization of cellulose ester

[0287] The results showing the DS and Mw for Examples 1-2 to 1-8 are listed in Table 1.2 below.

[0288] DS and Mw were calculated as follows:

[0289] Degree of Substitution

[0290] The degree of substitution of the substituents on the cellulose ester backbone was calculated using proton nuclear magnetic resonance spectroscopy. The cellulose ester was subjected to gel permeation chromatography in stabilized tetrahydrofuran. The instrument was an Agilent 1260 consisting of a degasser, an isocratic pump with a flow rate of 1.0 milliliter per minute, an autosampler with an injection volume of 25 microliters, a column oven set to 28 °C, and a refractive index detector at 28 °C. The column set consisted of an Agilent PLgel 5-micron guard column, Mixed-C, and Oligopore in series. The system was calibrated with monodisperse polystyrene standards with molecular weights ranging from approximately 4 million to 162. The sample was prepared as follows: approximately 25 milligrams of sample was weighed in 10 milliliters of solvent with the addition of 10 microliters of toluene to be used as a flow rate marker, a stir bar was added to an 8-cc screw cap vial, and stirred until dissolved.

[0291] Molecular Weight

[0292] Molecular weights were determined by gel permeation chromatography. Gel permeation chromatography was performed on cellulose esters in stabilized tetrahydrofuran. The instrument was an Agilent 1260 consisting of a degasser, an isocratic pump at a flow rate of 1.0 mL / min, an autosampler with an injection volume of 25 μL, a column oven set at 28 °C, and a refractive index detector at 28 °C. The column set consisted of an Agilent PLgel 5 micron guard column, Mixed-C, and Oligopore in series. The system was calibrated with monodisperse polystyrene standards ranging from approximately 4 million to 162. The sample was prepared as follows: approximately 25 mg of sample was weighed in 10 mL of solvent with the addition of 10 μL of toluene to be used as a flow rate marker, a stir bar was added to an 8 dram screw cap vial, and stirred until dissolved.

[0293] Preparation of microparticles

[0294] Examples 2-1 to 2-13:

[0295] Microparticles were prepared from the cellulose esters of Examples 1-2 to 1-8. Examples 2-1 to 2-11 were made by jet milling as described below, while Examples 2-12 and 2-13 were made by the emulsion method.

[0296] Comparative Examples 1 to 3:

[0297] Microparticles were also prepared from commercial cellulose esters by jet milling as described below.

[0298] The results for each microparticle, including which cellulose ester was used, particle size (PS), oil uptake, and surface area (SSA / BET), are listed in Table 1.2 below.

[0299] Jet Milling

[0300] There are a variety of jet milling configurations that can be used to reduce the size of particles. Such configurations are discussed in A. Chamayou and J. A. Dodds, Air Jet Milling, Handbook of Powder Technology, Vol. 12, Chapter 8, 2007 (“Chamayou”). The discussion of Chamayou is incorporated herein by reference in its entirety. Figure 7An example of a fluid bed opposed jet mill that can be used to reduce the size of the cellulose ester particles described in Table 1 below (for use as identified as microparticles produced by jet milling) is provided. A jet milling process is used to reduce the particle size of the cellulose ester from 300-900 μιη to about 10 μιη. The operation of this basic jet mill is as follows: The cellulose ester is placed into a hopper and introduced into the top of the mill ("FEED IN") typically through a double valve arrangement (or through a syringe). The cellulose ester particles fall under the influence of gravity to the bottom of the mill where they are entrained into one of three high pressure air streams that are geometrically oriented toward each other, creating a so-called "attrition zone". Within the attrition zone, the size of the cellulose ester particles is reduced via inter-particle collisions. The size-reduced particles are then transported upward by mass transport in the vertical air stream (fluid bed) to be ultimately carried into a classifier. The classifier enables particles below a desired minimum size to be removed from the mill ("FINE OUT"). Particles that exceed a maximum size will be excluded from the classifier and sent back to the fluid bed to ultimately fall back into the attrition zone for further size reduction. Particles that fall within the desired size range are ejected from the classifier into an appropriate product container. There are many control parameters for optimizing production rate, particle size, and particle size distribution shape, including but not necessarily limited to, classifier rotor speed, air nozzle pressure, and bed level.

[0301] Emulsion process

[0302] A clean, dry 3-liter kettle flask (with a baffle) equipped with two overhead mechanical stirrers and a bottom drop valve is prepared. The kettle is charged with 700-1,300 g of deionized water, 6-13 g of Tergitol 15-S-40, and 0-1.0 g of PEG-100 stearate. 7-12 g of a colloidal protective agent (low, medium, or high viscosity carboxymethylcellulose or methylcellulose) is added to the stirred aqueous mixture over 15 minutes. The mixture is stirred at ambient temperature for one hour or until homogeneous.

[0303] A separate clean, dry 2-liter kettle flask equipped with an overhead mechanical stirrer and a bottom drop valve is prepared. A coating solution consisting of 10-100% cellulose ester is prepared using 0-5.0 parts of a C1-C4 alkyl acetate, 0-1.0 parts of a C1-C3 alcohol, and 0-0.80 parts of deionized water (based on the mass of cellulose ester used). The mixture is stirred at ambient temperature until homogeneous.

[0304] The coating solution was added to a 3 liter kettle under vigorous agitation (250-500 rpm) over 30 minutes. After the addition was complete, the emulsion was circulated through a flow cell containing a high shear mixer (0-12,000 rpm) at a rate of 100-300 mL / min for 45-60 minutes.

[0305] After the high shear mixing time was complete, the emulsion was pumped into a 5 gallon drum containing 4000-6000 g of deionized water equipped with a single layer of overhead mechanical agitation at 250-500 rpm for 0-16 hours. After the hold time, centrifugation was performed to isolate the spherical microparticles. The microparticles were suspended in 1-2 L of deionized water and centrifuged again. This washing process was repeated once.

[0306] The microparticles were placed in a mixer with sigma blades and dried under vacuum (100-400 mm Hg) at 50-100 °C for 16 hours. The recovery yield was about 75-85%. Typical / target particle size data was as follows: D(10) = 3.07 pm; D(50) = 8.20 pm; D(90) = 22.6 pm; the volume-based average particle size was about 11.3 pm.

[0307] Characterization of microparticles

[0308] The microparticles were characterized by measuring particle size (PS), oil uptake, and surface area (SSA / BET).

[0309] Particle Size

[0310] The particle size distribution and mean / average particle size were determined by analyzing the microparticles using light scattering according to the following procedure using a Malvern Mastersizer 3000 (Hydro MV dispersion unit):

[0311] 1. Sample Preparation

[0312] a. Pour 1.5 ounces of isopropyl alcohol into a 2.5 ounce glass jar.

[0313] b. Scoop 0.5 grams of sample into the jar and shake vigorously

[0314] 2. Instrument Initialization

[0315] a. Fill the Hydro MV dispersion unit completely with isopropyl alcohol and set the stirrer speed to 3,500 RPM.

[0316] b. Allow the isopropyl alcohol to circulate for about one minute, then open the bleed valve to release the liquid to the waste bucket.

[0317] c. Repeat steps a and b (dispersion unit needs to be rinsed twice).

[0318] d. Fill the Hydro MV dispersion unit with isopropyl alcohol to half full and set the stirrer speed to 3,500 RPM. Allow the isopropyl alcohol to circulate for 5 minutes until the energy on the detector has stabilized.

[0319] e. Set the stirrer speed to 3,000 RPM, then initialize the instrument and measure the background.

[0320] 3. Sample Measurement

[0321] a. Set the obscuration between 2% and 5%. Set the sample measurement time for both red and blue light measurements to 3 seconds.

[0322] b. Add the sample suspension dropwise until the desired obscuration is reached (approximately 4%).

[0323] c. Measure the sample.

[0324] d. After the first measurement, sonicate the sample at 50% power for 120 seconds.

[0325] e. After sonication, wait for the light energy to stabilize (usually less than a minute) and then measure the sample again.

[0326] 4. Cleanup

[0327] a. Open the bleed valve to release the liquid containing the sample into the waste bucket.

[0328] b. Repeat steps 2a through 2c to rinse the dispersion unit.

[0329] c. After all of the cellulose ester samples have been measured, rinse the Hydro MV dispersion unit twice with Millipore water.

[0330] d. Place the lid on the Hydro MV dispersion unit and close the software.

[0331] The above procedure can be used to determine the D10, D50, and D90 particle sizes, as well as the D[4,3] mean particle size. Unless otherwise noted in the examples, the particle size (PS) refers to the D[4,3] mean particle size.

[0332] Oil Uptake

[0333] Oil uptake was measured using ASTM D281 standard test method to determine the oil uptake capacity of the particulate being tested. In this method, a known amount of particulate was weighed in a glass vial and olive oil was carefully added dropwise to the absorbing particulate with a plastic pipette. After every two drops of oil was added, the particulate was thoroughly mixed with the oil by mixing with a steel spatula with a sharp edge. The test was completed when sufficient oil was incorporated with the particles to produce a very hard, putty-like paste that would not break apart and separate. The dropper vial containing the oil was accurately weighed. The oil uptake capacity or oil absorption of the particulate was calculated by the following equation: where A = initial weight of the dropper vial with oil, B = final weight of the dropper vial with oil, and W = weight of the starting particulate sample (grams). Oil uptake (g / g or g / 100g) = (A-B) / W

[0334] SSA / BET

[0335] The surface area of the particulate was measured using a Micrometrics ASAP 2020 instrument according to ISO 9277 using the gas adsorption BET method.

[0336] The measurement was performed using the following procedure:

[0337] 1) 0.5-1 gram of sample was degassed overnight at 60°C. If the degassing was not sufficient, the temperature was increased by 10°C, but below 100°C, to avoid irreversible changes on the surface.

[0338] 2) The sample mass was obtained by the difference in weight of the empty sample tube and the sample tube filled with sample after degassing.

[0339] 3) The specific surface area analysis was performed using krypton adsorption at 77K

[0340] 4) Seven relative pressures from 0.06 to 0.20 were collected and fitted for BET specific surface area analysis.

[0341] The test results for PS, oil uptake, and surface area of the particulate being tested are contained in Table 1.2 below.

[0342] Table 1.2: Particulate

[0343]

[0344]

[0345] * Pre-milled to 300 microns in a mechanical mill prior to jet milling

[0346] Biodegradability test

[0347] Certain of the cellulose esters and microparticles in the above examples were tested for biodegradability according to test method OECD 301B or OECD 301F.

[0348] OECD 301B Test Description

[0349] A measured volume of mineral medium is inoculated with a known concentration of test substance, which acts as a nominal source of organic carbon. The medium is placed in a closed flask and agitated at a constant temperature (+1 °C or closer) for up to 60 days.

[0350] The degradation of the test substance is monitored over a 60-day period by measuring the amount of carbon dioxide produced. The carbon dioxide is captured using barium hydroxide or sodium hydroxide and quantified by titration of the remaining hydroxide or by measuring inorganic carbon.

[0351] The amount of carbon dioxide produced by the test substance, after adjustment for any carbon dioxide produced by the blank inoculum, is expressed as a percentage of theoretical carbon dioxide (ThCO2). In addition, the extent of biodegradation can be calculated by analyzing the change in dissolved organic carbon (DOC) levels at the beginning and end of the incubation period.

[0352] OECD 301F Test Description

[0353] A measured volume of mineral medium is inoculated with a known concentration of test substance, which acts as a nominal source of organic carbon. The medium is placed in a closed flask and agitated at a constant temperature (+1 °C or closer) for up to 60 days.

[0354] The amount of oxygen consumed is determined using one of two methods: either by measuring the amount of oxygen required to maintain a constant gas volume in a respirometer flask (generated by electrolysis), or by monitoring changes in volume or pressure in the apparatus (or a combination of both).

[0355] Any carbon dioxide produced during the process is absorbed using a potassium hydroxide solution or another suitable absorbent. The amount of oxygen utilized by the microbial population during biodegradation of the test substance is calculated by subtracting the amount of oxygen consumed by the blank inoculum (run in parallel). This value is expressed as a percentage of theoretical oxygen demand (ThOD) or, less desirably, chemical oxygen demand (COD).

[0356] These tests were performed on cellulose ester Examples 1-3, 1-4, 1-5, 1-6, and CA-398-6, and microparticle Examples 2-1, 2-2, and Comparative Example 1. The results are listed in Table 1.3 below.

[0357] Table 1.3: Biodegradability Tests

[0358] Examples Form Test method Biodegradation (%) Example 2-1 Microparticles OECD 301 B 83.4 Example 2-2 Microparticles OECD 301 F 67.9 Example 1-3 CAB OECD 301 F 60 Example 1-4 CAB OECD 301 F 67 Example 1-5 CAB OECD 301 F 62.7 Example 1-6 CAB OECD 301 F 62.9 Comparative Example 1 Microparticles OECD 301 F 76 CA-398-6 CA OECD 301 F 32.5

[0359] A review of Table 1.3 reveals that the percentage biodegradability of the microparticles is higher compared to the source cellulose ester used to make the microparticles, and Examples 1-4 have the highest percentage biodegradability among the cellulose esters tested.

[0360] Cosmetic formulation

[0361] The cosmetic formulations prepared and tested include a water / oil (W / O) liquid foundation, a W / O sunscreen, a lipstick, and a W / O emulsion.

[0362] Water / Oil (W / O) Liquid Foundation

[0363] The ingredients used to prepare the W / O liquid foundation formulation are listed in Table 2.

[0364] Table 2: Ingredients for W / O Liquid Foundation

[0365]

[0366] Preparation of W / O Liquid Foundation

[0367] The formulation for the W / O liquid foundation was prepared according to the following method:

[0368] 1. Combine Phase A (melt polyhydroxy stearic acid first) and pass through 3 roll mills 3 times;

[0369] 2. Combine Phase B and mix with overhead stirrer (large dissolver / 400 RPM);

[0370] 3. Add Phase A to Phase B and homogenize with Ultra Turax (5k RPM) for 5 minutes;

[0371] 4. Combine Phase C and stir with magnetic stir bar until dissolved;

[0372] 5. Slowly add Phase C to A-B phase while mixing with Ultra Turax (10k RPM);

[0373] 6. Homogenize at 10k rpm for 10 min;

[0374] 7. Add ingredients of Phase D one at a time to emulsion while mixing at 5k RPM;

[0375] 8. Add microparticles while mixing with Ultra Turax at 10k rpm.

[0376] Testing

[0377] The W / O liquid foundation test includes an optical effect test and a sensory panel evaluation.

[0378] The optical effect is evaluated using an in vitro skin mimicking substrate in the form of synthetic textured leather with a topography pattern. The application procedure of the formulation product on this substrate is as follows.

[0379] 1. Cut a large piece of synthetic leather into 5 x 5 cm 2 squares with scissors;

[0380] 2. Gently mix the cosmetic formulation with a pipette or a wooden stick;

[0381] 3. Weigh 0.05 g of the cosmetic formulation in total on an analytical balance and drop it evenly on 9 different points on the textured leather substrate;

[0382] 4. Rub and spread the product with a circular motion with fingers wearing safety gloves for 1 min;

[0383] 5. Let the cosmetic product dry for 5 min, visually evaluate the sample (at an angle of about 45 degrees) and grade the optical effect and coverage (1-5), ensuring that all the lighting conditions for the evaluation are the same;

[0384] 6. Take a picture for documentation purposes.

[0385] Table 3: Particulate in W / O liquid foundation

[0386] Microparticles Optical effect rating (1-5) No microparticles 2.5 5 wt% Nylon-12 3.5 5 wt% polymethyl methacrylate 3.5 5 wt% Example 2-2 4 5 wt% cellulose 3.25 5 wt% cellulose acetate 3.75 5 wt% boron nitride 3 5 wt% silica 3.75

[0387] The optical effect test was also performed on commercial liquid foundation products. The results are shown in Table 4 below.

[0388] Table 4: Particulate in commercial products

[0389]

[0390] The sensory panel test is performed by 5-10 panelists. The products are randomly assigned a number or letter for blind testing. A small amount (10-30 mg) of product is applied to the back of the hand and then massaged with the fingertips, spreading in a circular motion. Each person is asked to rank from 1 to 5 the order of intensity for each of the following sensory attributes:

[0391] Spreadability: evaluation of the ability of the sample to spread out and continue to provide consistent coverage when applied to the skin in a wet state, with 1 indicating difficult to spread out consistently and 5 indicating very easy to spread out consistently;

[0392] Smoothness: evaluation of the degree of slip or ease of movement (or glide) of the sample when applied to the skin, with 1 indicating difficult to move and 5 indicating very easy to move;

[0393] Smoothness: evaluation of how smooth the sample feels to the touch after it has been applied and dried, where 1 indicates rough and 5 indicates very smooth;

[0394] Covering power: evaluation of how uniform the colour / pigmentation is after the sample has been applied and dried, where 1 indicates uneven and 5 indicates highly uniform;

[0395] Blurring: evaluation of how diffuse the covered area appears and the effect of optically blurring / concealing blemishes / defects by manipulating light scattering to hide imperfections, where 1 indicates poor blurring / concealing ability and 5 indicates very good blurring / concealing effect;

[0396] Oil light reduction: evaluation of how much the applied sample reduces the oil light (or shine) and how low the contrast with the skin is, where 1 indicates an oily or shiny and high contrast appearance and 5 indicates a very matte (no oil light) and low contrast appearance.

[0397] After each evaluation, the skin was cleaned of residual product with a wipe and the next product was evaluated. The results as an average rating for each attribute are shown in Table 5 below.

[0398] Table 5: Effect of particle size on sensory attributes: ratings 1-5

[0399]

[0400] The shape of certain microparticles has been identified and is listed in Table 6 below. The effect of shape on sensory testing was evaluated. The results are shown in Table 7 below.

[0401] Table 6: Shape: Spherical vs. Spheroidal

[0402] Microparticles INCI Shape Example 2-2 Cellulose acetate butyrate Non-spherical (spheroid) Comparative Example 2 Cellulose acetate Non-spherical (spheroid) Example 2-12 Cellulose acetate butyrate Spherical Example 2-13 Cellulose acetate butyrate Spherical

[0403] Table 7: Effect of shape on sensory attributes: ratings 1-5

[0404]

[0405] A review of Tables 5 to 7 reveals that larger particle sizes generally result in higher ratings for spreadability, slipperiness and smoothness, but have less impact on ratings for blurring effect and oil light reduction effect (see Table 5); while spherical particles result in higher ratings for spreadability, slipperiness and smoothness, but generally have lower ratings for covering power, blurring effect and oil light reduction effect (see Tables 6 and 7).

[0406] Water / oil (W / O) sunscreen

[0407] The ingredients used to prepare the W / O sunscreen formulation are listed in Table 8.

[0408] Table 8: Ingredients for W / O sunscreen

[0409]

[0410]

[0411] Preparation of W / O sunscreen

[0412] The formulation of the W / O sunscreen was prepared according to the following method:

[0413] 1. Combine Phase B (oil phase) and mix with overhead stirrer using large dissolver at 400 RPM;

[0414] 2. Heat oil phase to 50°C;

[0415] 3. Combine Phase C (water phase) and stir with magnetic stir bar until well mixed;

[0416] 4. Add zinc oxide dispersion (Phase A) to oil phase;

[0417] 5. Once Phase A is well mixed into Phase B, transfer to Silverson mixer and mix at 5K RPM for 5 minutes;

[0418] 6. Slowly add Phase C-D to Phase A-B while mixing with Silverson (10K RPM);

[0419] 7. Homogenize at 10K RPM for 10 minutes;

[0420] 8. Post-add Phase E (microparticles) while mixing with Silverson at 10K RPM.

[0421] Testing

[0422] The W / O sunscreen testing included determining the sun protection factor (SPF) and absorbance at different wavelengths. The SPF was determined according to standard industry practices for measuring in vitro SPF. Additional formulations similar to the above were prepared, but without the zinc oxide dispersion paste (UV filter) in the formulation, to test the absorbance with and without the UV filter. The absorbance was measured using a spectrophotometer. The formulations tested and results are shown in Tables 9 and 10 below.

[0423] Table 9: In vitro SPF results

[0424]

[0425] Table 10: Absorbance

[0426]

[0427]

[0428] A review of Tables 9 and 10 found that formulations containing Example 2-1 microparticles had higher SPF than formulations containing nylon-12 or PMMA, and that the inclusion of Example 2-1 microparticles increased UV absorption when a UV filter was present.

[0429] Lipstick

[0430] The ingredients used to make the lipstick formulations are listed in Table 11.

[0431] Table 11: Lipstick Ingredients

[0432]

[0433] Preparation of Lipstick

[0434] The lipstick formulations were prepared according to the following method:

[0435] Lipstick base :

[0436] 1. Heat Part A to 80°C under propeller mixing.

[0437] 2. Add Part B. Mix for 10 minutes until uniform.

[0438] 3. Add Part C. Mix until uniform.

[0439] 4. Cool.

[0440] Incorporation of different microparticles / powders in lipstick base:

[0441] 1. Weigh the required amount of lipstick base;

[0442] 2. Heat to 80°C under propeller mixing;

[0443] 3. Add microparticles to the melted lipstick base and mix for 10 minutes until uniform;

[0444] 4. Pour the formulation into a lipstick mold and cool.

[0445] Testing

[0446] The lipstick testing included determining the ability of the lipstick to color a substrate by measuring the change in color with microparticle / powder loading.

[0447] Microparticles / powders tested:

[0448] Lipstick samples were made with 0%, 1%, 3%, 6%, 9% loading of the microparticles / powders incorporated into the lipstick base. The microparticles / powders used are listed in Table 12.

[0449] Table 12: Microparticles / powders used in lipstick testing

[0450]

[0451]

[0452] Color test procedure:

[0453] Lipstick was applied to silicone substrates (to mimic skin). To compare different formulations, a consistent application method was used for the substrate coupons. A handheld spectrophotometer (Konica Minolta 2600d) was used to measure the L*a*b* color values of the colored coupons. From these values, AL* and Da* were calculated with the 0% loading as the starting value. Decreasing L* values reflect the coupons getting darker (or more intense color) and increasing Da* values reflect the enhancement of the red color (pigment used for the lipstick base is Red 40 Lake). The coupons were evaluated visually and rated for the evenness of coverage on a scale of 0 to 5 (5 = best color uniformity). Results are shown in Tables 13-15 below.

[0454] Table 13: AL* as a function of loading

[0455]

[0456] A review of Table 13 finds that the addition of the Example 2-1 microparticles results in a decrease in AL* values, similar to nylon-12, both of which result in a darker applied lipstick color (or more intense color and desired effect). The best performance is achieved at 6% loading. Example 2-1 outperforms silica, PMMA, and starch in terms of color intensity, and cellulose is the most significant in enhancing color intensity.

[0457] Table 14: Da* as a function of loading

[0458]

[0459] A review of Table 14 finds that the addition of the Example 2-1 microparticles results in an enhancement of the red color (or an increase in Da* values), similar to nylon-12. The best performance is achieved at 6% loading. Example 2-1 outperforms silica, PMMA, and starch in terms of red color enhancement, and cellulose is the most significant in enhancing red color.

[0460] Table 15: Visual evaluation of evenness of coverage

[0461]

[0462] A review of Table 15 reveals that Example 2-1 and silica exhibited the best pigment distribution and best hiding balance, followed by nylon-12 and PMMA. Cellulose and starch exhibited the worst hiding balance.

[0463] W / O emulsion

[0464] The ingredients used to prepare the non-polar oil-based simplex W / O emulsion formulation are listed in Table 16.

[0465] Table 16: Ingredients for W / O emulsion

[0466]

[0467] Preparation of W / O emulsion

[0468] The W / O emulsion formulation was prepared according to the following method:

[0469] 1. Combine Phase A and stir with an overhead mixer (500 rpm) until homogeneous;

[0470] 2. Combine Phase B and stir until dissolved (use a magnetic stir bar);

[0471] 3. Add Phase B to Phase A while mixing with high shear (10 k rpm Ultra Turax mixer);

[0472] 4. Homogenize at 10 k rpm for 5 minutes.

[0473] Testing

[0474] The W / O emulsion testing included gloss reduction testing. Gloss reduction was evaluated by using a BYK micro-TRI gloss meter. Sample preparation and gloss reduction measurements were performed according to the following procedure.

[0475] 1. Cut a template to match the bottom of the gloss meter using painter’s tape and tape it to the bottom of the gloss meter before making any measurements (to prevent seepage into the components of the gloss meter);

[0476] 2. Draw down the formulation sample on Leneta paper using a 4 mil squaredown bar by pulling the bar from top to bottom at a constant speed / pressure while moving the Leneta paper down;

[0477] 3. Gloss is measured initially at three angles (20°, 60° and 85°) and then every 5 minutes for 30 minutes, as high gloss surfaces with a gloss unit (GU) of 70 or higher should be measured using the 20° angle, while semi-gloss surfaces with a GU ranging from 10-70 should be measured using the 60° angle;

[0478] 4. After the initial measurement, ensure that the gloss meter is placed back in the same position for subsequent measurements to obtain accurate data, noting that the gloss meter will leave an imprint on the drawdown film showing where the previous measurement was taken;

[0479] 5. Read the readings three times for each sample without moving the gloss meter and take the average reading, and perform 2 drawdowns for each sample material;

[0480] 6. For comparison and reporting, use the GU values at 60° and report the data every 30 minutes.

[0481] Gloss reduction values are calculated with a 0% loading (or base emulsion) as a starting value, and gloss reduction is reported as a percentage change (reduction) in GU. The microparticles used in the test formulations and the gloss reduction are shown in Table 17.

[0482] Table 17: Gloss Results for W / O Emulsions

[0483] Microparticles Gloss reduction (%) Example 2-1 85 Cellulose (and) zinc stearate 54 Nylon-12 31 Boron nitride 16 Silica 83

[0484] A review of Table 17 finds that the emulsion formulation containing the microparticles of Example 2-1 has the highest gloss reduction.

[0485] Cellulose Ester Solubility Test

[0486] CE coatings were prepared as shown in Table 18 below to determine the solubility of a CE (such as cellulose acetate butyrate (CAB), Example 1-1) in a solvent system containing ethyl acetate (EA), n-propanol (nPrOH), and water. The preparation of Example 3-1 is shown below.

[0487] Preparation of CE Coatings

[0488] CE coatings are prepared as follows: The corresponding amounts of solvent system shown in Table 18 are loaded into a dry 250 mL one-necked round-bottom flask equipped with a magnetic stirrer. The solvent system is stirred, and then the corresponding amount / type of CAB is loaded into the flask. The CAB is loaded into the flask by slowly metering the solid at a controlled rate, such that the stirring vortex moves the solid particles into the solvent system without forming large clumps of powder on the top of the liquid phase. This mixture of solvent and CAB is stirred at room temperature for 45 minutes. If the mixture becomes homogeneous within this time period, the coating is determined to be "soluble". If the solid particles are still not dissolved in the solvent system after 60 minutes, the coating is determined to be "insoluble".

[0489] In coatings 3-1, 3-2, and 3-3, the solvent systems contain varying amounts of ethyl acetate and n-propanol, but no water. In coatings 3-1a, 3-2a, and 3-3a, water is added to the solvent system. That is, the solvent systems of coatings 3-1 and 3-1a, 3-2 and 3-2a, and 3-3 and 3-3a contain the same amounts of ethyl acetate and n-propanol, and the only difference between the respective coatings is the addition of water.

[0490] In coatings 3-4, the amount of CAB contained in the CE coating is increased so that its CAB mass % matches that of the anhydrous coatings (i.e., coatings 3-1, 3-2 and 3-3).

[0491] Table 18

[0492]

[0493]

[0494] It is worth noting that anhydrous CE coatings cannot dissolve the CE they contain. For example, coating 3-1 provides a blocky and heterogeneous mixture, while coatings 3-2 and 3-3 initially provide a stirable slurry, but become blocky and heterogeneous after a few minutes.

[0495] In contrast, coating 3-1a provides a stirable slurry, rather than a blocky slurry. Coatings 3-2a and 3-3a provide homogeneous mixtures in which CE dissolves in the solvent system within 3 minutes.

[0496] As shown in coatings 3-4, increasing the mass of CE in the CE coating also provides a homogeneous mixture in which CE dissolves in the solvent system within 3 minutes. In other words, increasing the CAB% of the CE coating does not appear to have a negative impact on the solubility of CE in the solvent system.

Claims

1. A cosmetic composition comprising biodegradable microparticles, wherein the biodegradable microparticles comprise mixed cellulose ester, wherein the biodegradable microparticles exhibit biodegradability of at least 50% at 60 days according to at least one of the OECD 301B, OECD 301C, or OECD 301F test methods, wherein the mixed cellulose ester comprises (a) an average degree of substitution ("DS") of acetyl substituents in the range of 0.1 to 2.3 Ac , (b) an average degree of substitution ("DS Pr ") of propionyl substituents in the range of 0.1 to 1.5 or an average degree of substitution ("DS Bu ") of butyryl substituents in the range of 0.1 to 1.5, and (c) an average degree of substitution ("DS") of hydroxyl substituents in the range of 0.6 to 2.

8. OH ​ 2. The cosmetic composition of claim 1, wherein the cosmetic composition comprises at least 0.1 wt.%, at least 0.5 wt.%, at least 1 wt.%, at least 2 wt.%, at least 3 wt.%, at least 4 wt.%, at least 5 wt.%, at least 6 wt.%, at least 7 wt.%, at least 8 wt.%, at least 9 wt.%, at least 10 wt.%, at least 11 wt.%, at least 12 wt.%, at least 13 wt.%, at least 14 wt.%, or at least 15 wt.% of the biodegradable microparticles.

3. The cosmetic composition of claim 1 or 2, wherein the biodegradable microparticles have an average sphericity of less than 50% or less than 40%.

4. The cosmetic composition of any one of claims 1-3, wherein the cosmetic composition is a foundation, a sunscreen, a lipstick, a mascara, an eye shadow, a lotion, a dry shampoo, a liquid shampoo, a body wash, a lotion, a hair conditioner, a skin moisturizer, a facial cleanser, a tablet, a foot powder, a baby powder, a shaving cream, or a shaving gel.

5. The cosmetic composition of any one of claims 1-4, wherein the cosmetic composition comprises at least 1 wt.% and less than 60 wt.% of at least one, two, three, four, or five cosmetic additives, wherein the cosmetic additives comprise a colorant, an oil, a wax, a fatty acid, an alcohol, an ester, a hydrocarbon, a silicone oil, a surfactant, a metallic soap, a humectant, a thickening agent, a UV absorber, an antioxidant, an oil absorber, an exfoliant, water, or a combination thereof.

6. The cosmetic composition of any one of claims 1-5, wherein the biodegradable microparticles exhibit a unimodal particle size distribution with a span of at least 0.5 and / or less than 3.0, and wherein the biodegradable microparticles have a D[4,3] particle size in the range of 1 to 50 microns.

7. The cosmetic composition of any one of claims 1-6, wherein the biodegradable microparticles have a butyric acid content of less than 100 ppmw, and / or wherein the biodegradable microparticles have an acetic acid content of less than 500 ppmw.

8. The cosmetic composition of any one of claims 1-7, wherein the biodegradable microparticles exhibit biodegradability of at least 55% or at least 60% at 60 days according to at least one of the OECD 301B, OECD 301C, or OECD 301F test methods.

9. The cosmetic composition of any one of claims 1-8, wherein the mixed cellulose ester exhibits biodegradability of at least 45%, at least 50%, at least 55%, at least 60% at 60 days according to at least one of the OECD 301B, OECD 301C, or OECD 301F test methods.

10. The cosmetic composition of any one of claims 1-9, wherein the DS Ac is at least 1.

5.

11. The cosmetic composition of any one of claims 1-10, wherein the DS Ac less than 2.

3.

12. The cosmetic composition of any one of claims 1-11, wherein the DS Pr is at least 0.

1.

13. The cosmetic composition of any one of claims 1-12, wherein the DS Pr less than 0.

5.

14. The cosmetic composition of any one of claims 1-13, wherein the DS Bu is at least 0.1 or at least 0.

2.

15. The cosmetic composition of any one of claims 1-14, wherein the DS Bu less than 0.5 or less than 0.

3.

16. The cosmetic composition of any one of claims 1-15, wherein the DS OH is at least 0.

7.

17. The cosmetic composition of any one of claims 1-16, wherein the DS OH less than 1.

2.

18. The cosmetic composition of any one of claims 1-17, wherein the biodegradable microparticles comprise at least 75% by weight of the mixed cellulose ester.

19. The cosmetic composition of any one of claims 1-18, wherein the biodegradable microparticles consist essentially of the mixed cellulose ester.

20. The cosmetic composition of any one of claims 1-19, wherein the biodegradable microparticles have a polydispersity index of less than 0.

8.

21. The cosmetic composition of any one of claims 1-20, wherein the biodegradable microparticles have a sphericity of at least 10%.

22. The cosmetic composition of any one of claims 1-21, wherein the biodegradable microparticles exhibit an oil absorption of at least 50 mL / 100 g measured using test method ASTM D281, wherein mineral oil is used in place of castor oil.

23. A cosmetic composition comprising 0.5% to 15% by weight of biodegradable microparticles, wherein the biodegradable microparticles comprise a mixed cellulose ester, wherein the biodegradable microparticles exhibit biodegradability of at least 50% at 60 days according to at least one of the OECD 301B, OECD 301C, or OECD 301F test methods, wherein the biodegradable microparticles have an average BET surface area in the range of 0.1 to 15 m 2 / g. wherein the mixed cellulose ester comprises (a) an average degree of substitution ("DSac") of acetyl substituents in the range of 1.5 to 2.3 Ac ”, (b) an average degree of substitution ("DS") of butyryl substituents in the range of 0.1 to 0.3 Bu ”) of 0.1 to 0.3, and (c) an average degree of substitution ("DS") of hydroxyl substituents in the range of 0.7 to 1.

1. OH ”) of 0.7 to 1.

1.

24. The cosmetic composition of claim 23, wherein the biodegradable microparticles consist essentially of the mixed cellulose ester.

25. The cosmetic composition of any one of claims 23-24, wherein the DS OH in the range of 0.7 to 1.

0.

26. A method for forming a cosmetic composition, the method comprising: (a) providing a plurality of biodegradable microparticles comprising a mixed cellulose ester, wherein the biodegradable microparticles exhibit biodegradability of at least 50% at 60 days according to at least one of the OECD 301B, OECD 301C, or OECD 301F test methods, wherein the mixed cellulose ester comprises (i) an average degree of substitution ("DSac") of acetyl substituents in the range of 1.5 to 2.3 Ac ”, (ii) an average degree of substitution ("DS Pr ") of propionyl substituents in the range of 0.1 to 0.3 or an average degree of substitution ("DS Bu ") of butyryl substituents in the range of 0.1 to 0.3, and (iii) an average degree of substitution ("DS") of hydroxyl substituents in the range of 0.7 to 1.1 OH ”) ; and (b) combining the biodegradable microparticles with one or more cosmetic additives, thereby forming a cosmetic precursor mixture; and (c) forming the cosmetic composition from the cosmetic precursor mixture, wherein the cosmetic composition comprises at least 2% by weight of the biodegradable microparticles.

27. The method of claim 26, wherein the biodegradable microparticles are produced by jet milling and have an average sphericity in the range of 5% to 30%.

28. The method of any one of claims 26-27, wherein the cosmetic composition is a foundation, a sunscreen, a lipstick, a mascara, an eye shadow, a lotion, a dry shampoo, a liquid shampoo, a body wash, a lotion, a hair conditioner, a skin moisturizer, a facial cleanser, a tablet, a foot powder, a baby powder, a shaving cream, or a shaving gel.

29. The method of any one of claims 26-28, wherein the biodegradable microparticles have a D[4,3] average particle size in the range of 1 to 10 microns.

30. The method of any one of claims 1-29, wherein the biodegradable microparticles exhibit a biodegradability of at least 60% at 60 days according to the OECD 301F test method.

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