WO2023108326A1

WO2023108326A1 - Use of C20-36 fatty alcohol in preparation of O/W emulsions with low viscosity

Info

Publication number: WO2023108326A1
Application number: PCT/CN2021/137382
Authority: WO
Inventors: Guangyuan MA; Jiejun TONG; Qisong ZHANG; Yexiang Zhang; Jianmin Xu; Hans Henning Wenk; Chen Liu
Original assignee: Evonik Operations Gmbh
Priority date: 2021-12-13
Filing date: 2021-12-13
Publication date: 2023-06-22

Abstract

Use of a C20-36 fatty alcohol to prepare an O/W emulsion with lower viscosity compared with the O/W emulsion wherein the C20-36 fatty alcohol is replaced by a C16-18 fatty alcohol. An O/W emulsion and a method to produce an O/W emulsion with lower viscosity was also provided.

Description

Use of C20-36 fatty alcohol in preparation of O/W emulsions with low viscosity

Technical Field

The invention relates to the application of C20-36 fatty alcohols in oil-in-water (O/W) emulsions.

Background art

It is well known that when formulating O/W emulsions, long chain fatty alcohols with a carbon chain length of 16-18 are often added to stabilize the emulsion, to increase the viscosity and to obtain a better texture. Adding approximately 1-3 wt. %long straight chain fatty alcohols to the emulsification system increases the viscosity of the formulation and makes the emulsion formulation more stable.

However, low-viscosity emulsions are also in demand in the market. Formulators are facing high viscosity issues by using (C16-C18) alkyl alcohol (cetyl stearyl alcohol) to stabilize low-viscosity emulsions. Furthermore, the high viscosity will make the preparation process difficult and will make it impossible to prepare a low-viscosity emulsion product.

Summary of the invention

The purpose of the invention is to overcome at least partly the viscosity issue due to the use of C16-18 fatty alcohols in O/W emulsions.

According to prior art, it is believed that C20-36 fatty alcohol has higher melting point than C16-C18 fatty alcohol, and thus should have a higher viscosity building effect. However, the inventors surprisingly found that when the carbon number of fatty alcohols increases e.g. from C16-18, to C20-36, the effect of viscosity building is much lower than for conventional long chain fatty alcohols, but the effects of the long chain fatty alcohols such as stabilizing the emulsion, are kept. Therefore, such C20-36 fatty alcohol is particularly suitable to prepare an O/W emulsion with relatively low viscosity.

The invention provides use of a C20-36 fatty alcohol to prepare an O/W emulsion with lower viscosity compared with the O/W emulsion wherein the C20-36 fatty alcohol is replaced by a C16-18 fatty alcohol.

Therefore, the invention provides a method to produce an O/W emulsion with lower viscosity than an O/W emulsion with C16-18 fatty alcohol, wherein the O/W emulsion is prepared using a C20-36 fatty alcohol, preferably to replace the C16-18 fatty alcohol.

It is obvious, that the term “replacement” in the aforementioned term refers to replacement of the same amount of C16-18 fatty alcohol in terms of weight.

The C16-18 fatty alcohol to be replaced in this context is a mixture consisting of 50 wt. -%C16-and 50 wt. %C18 straight chained alkanol.

The invention provides an O/W emulsion, which comprises:

a) 0.5 wt. %-10 wt. %of a C20-36 fatty alcohol, based on the total weight of the emulsion.

The C20-36 fatty alcohol may be a mixture of fatty alcohols having numbers of carbon atoms from 20 to 36, for example from 20 to 34, from 20 to 32, from 20 to 30, from 24-36. A mixture of fatty alcohols may result in even lower viscosity in emulsions than separate fatty alcohols. The C20-36 fatty alcohol preferably is a mixture of fatty alcohols having numbers of carbon atoms selected from 20 to 36, and the amount of C20-30 fatty alcohol is more than 30 wt. %, 40 wt. %, or 50 wt. %, preferably more than 60 wt. %, more than 70 wt. %, more preferably more than 80 wt. %, more than 90 wt. %, more than 95 wt. %, more than 99 wt. %, with the weight percentages referring to all fatty alcohols comprised in the C20-36 fatty alcohol. The C20-36 fatty alcohol more preferably is a mixture of fatty alcohols having numbers of carbon atoms selected from 20 to 36, and the amount of C20-28 fatty alcohol is more than 15 wt. %, 18 wt. %, or 20 wt. %, preferably more than 30 wt. %, more than 40 wt. %, more preferably more than 50 wt. %, more than 60 wt. %, more than 70 wt. %, more than 80 wt. %, more than 90 wt. %, more than 95 wt. %, or more than 99 wt. %with the weight percentages referring to all fatty alcohols comprised in the C20-36 fatty alcohol.

Both mixtures of fatty alcohols having numbers of carbon atoms selected from 20 to 36 described above preferably comprise at least 3, more preferably at least 4 different fatty alcohols having numbers of carbon atoms selected from 20 to 30 or 20 to 28 respectively.

The emulsion preferably comprises at least 90 wt. %, preferably at least 95 wt. %more preferably at least 95 wt. %C20-36 fatty alcohol with the weight percentages referring to all fatty alcohols comprised in the total emulsion.

The emulsion is preferably free of C16-18 fatty alcohols. In some embodiments, the emulsion is free of other long chain fatty alcohols except the C20-36 fatty alcohol used.

Preferably the emulsion is free of monounsaturated linear or saturated branched acids having at least 18 carbon atoms.

Preferably the emulsion is free of other viscosity builders.

Preferably the emulsion comprises 1 wt. %-5 wt. %of an O/W emulsifier, based on the total weight of the emulsion.

The term “C20-36 fatty alcohol” in the context of the present invention means at least one fatty alcohol selected from the group consisting of fatty alcohols with a number of carbon atoms in the range of from 20 to 36. Thus, for example, a pure C24 fatty alcohol is considered a “C20-36 fatty alcohol” .

The term “fatty alcohol” in the context of the present invention preferably refers to primary branched and straight chained alkanols and alkenols, preferably straight chained alkanols.

The C20-36 fatty alcohol may have a carbon chain length of 20-35, 20-34, 20-33, 20-32, 20-31, preferably 20-30, for example, 20-29, 20-28, more preferably 20-26, for example, 20-24, or 20-22. Accordingly, the C20-36 fatty alcohol may comprise any C X-Y fatty alcohol (s) wherein X and Y are integers from 20 to 36, X is >=20, Y is <=36 and X<Y. When a C20-36 fatty alcohol has a carbon chain length Z that is less than 36, for example 20-26, it may also be described as C20-Z fatty alcohol, for example C20-26 fatty alcohol. Specific examples of the C20-36 fatty alcohol include, eicosanol (C20) , docosanol (C22) , tricosanol (C23) , tetracosanol (C24) , pentacosanol (C25) , hexacosanol (C26) , heptacosanol (C27) , octacosanol (C28) and triacontanol (C30) , dotriacontanol (C32) , psyllostearyl alcohol (C33) , inearnatyl alcohol (C34) , hexatriacontan-1-ol (C36) and any mixtures thereof. In some embodiments, 1-eicosanol, 1-docosanol, 1-tetracosanol, 1-hexacosanol, 1-octacosanol, triacontanol, 1-triacontanol or mixtures thereof are used as the C20-36 fatty alcohol.

Preferably the C20-36 fatty alcohol in the context of the instant invention is a mixture containing tetracosanol, hexacosanol, octacosanol, triacontanol, dotriacontanol and inearnatyl alcohol, with octacosanol, triacontanol and dotriacontanol accounting for at least 50 wt. -%of all C20-36 fatty alcohol.

The term “long chain fatty alcohol” in the invention refers to the fatty alcohol having a number of carbon atoms equal to 14 or higher.

The emulsifiers of the O/W emulsion may be selected from conventional emulsifiers suitable to prepare an O/W emulsion. The emulsifiers may be selected from e.g., polyglycerol ester emulsifiers, anion emulsifiers, polyethylene glycol (PEG) emulsifiers and sugar-based emulsifiers.

Polyglycerol ester emulsifiers may be selected from esters with a degree of polymerization of the polyglycerol in the range of from 2 to 16, preferably 3 to 10. The polyglycerol in the polyglycerol ester emulsifier preferably is esterified with carbon acids comprising at least one fatty acid, preferably with a carbon chain length selected from 6 to 30 carbon atoms, preferably 10 to 18 carbon atoms. The degree of esterification of the polyglycerol ester emulsifier preferably is in the range of from 1 to 12, preferably of from 1 to 6.

The polyglycerol ester emulsifiers may preferably be selected from long chained polyglycerol esters with fatty acid moiety out of the chemical class of linear or branched, saturated or unsaturated fatty acids with a chain length of C14-C30, preferable of C15-C24, especially preferable of C16-C20; and short chained polyglycerol esters prepared from linear or branched, saturated or unsaturated fatty acids with a chain length of C8-C12, preferably C10-C12.

Alternatively preferred the polyglycerol ester emulsifier is a polyglycerol esterified with a mixture of fatty acid containing at least 70 wt. -%docosanoic acid and lignoceric acid, wherein the weight percentages refer to all carbon acids esterified with the polyglycerol. Preferably in this context the weight ratio of docosanoic acid to lignoceric acid is in the range of 1: 1 to 1: 3, preferably of 1: 1.5 to 1: 2.

This alternatively preferred polyglycerol ester emulsifier has preferably a degree of esterification in the range of from 1 to 3, preferably of from 1.2 to 2.0, more preferably of from 1.3 to 1.8.

Examples of the polyglycerol ester emulsifier can be any one or more selected from the group consisting of:

polyglyceryl-6 stearate, polyglyceryl-6 behenate such as

CARE PBS 6 from Evonik Industries AG (Polyglyceryl-6 Stearate (and) Polyglyceryl-6 Behenate) , polyglyceryl-3 distearate, such as

NC MB from Evonik Industries AG (Polyglyceryl-3 Distearate; Glyceryl Stearate Citrate) , candelilla/jojoba/rice bran polyglyceryl-3 esters such as Emulium Kappa MB from Gatteforsse (Candelilla/Jojoba/Rice Bran Polyglyceryl-3 Esters (and) Glyceryl Stearate (and) Cetearyl Alcohol (and) Sodium Stearoyl Lactylate) , polyglyceryl-4 laurate (commercially available from Evonik with commercial name

CARE PL4) , polyglyceryl-6 laurate, polyglyceryl -6 caprylate/caprate, and polyglyceryl -3 caprylate/caprate.

Anion emulsifiers in the instant invention are preferably selected from the group of alkyl sulphates, alkyl ether sulphates, optionally alkoxylated sulphosuccinates, optionally alkoxylated methylsulphosuccinates, optionally alkoxylated sulphonates, optionally alkoxylated glycinates, optionally alkoxylated glutamates, optionally alkoxylated isethionates, optionally alkoxylated carboxylates, optionally alkoxylated anisates, optionally alkoxylated levulinates, optionally alkoxylated tartrates, optionally alkoxylated lactylates, optionally alkoxylated taurates, optionally alkoxylated alaninates, optionally alkoxylated phosphates, optionally alkoxylated sulphoacetates, optionally alkoxylated sulphosuccinamates, optionally alkoxylated sarcosinates and optionally alkoxylated phosphonates, preferably optionally alkoxylated sulphonates, alkyl sulphates, alkyl phosphates and alkyl ether sulphates.

Examples of the anion emulsifier can be any one or more selected from the group consisting of:

potassium cetyl phosphate (such as

CK 100 from Clariant or

K from DSM) , sodium lauryl sulfate, sodium cetearyl sulfate, such as

SX from BASF (Cetearyl Alcohol (and) Sodium Lauryl Sulfate (and) Sodium Cetearyl Sulfate) .

PEG emulsifiers are preferably selected from ethoxylated fatty acids and ethoxylated fatty alcohols.

Examples of the PEG emulsifier can be any one or more selected from the group consisting of:

PEG-100 stearate such as SIMULSOL ^TM 165 from SEPPIC (PEG-100 Stearate (and) Glyceryl Stearate) .

Sugar-based emulsifiers may be selected from alkyl polyglucosides, alkyl glucosides, sorbitan esters, sorbitol esters, sucrose esters, methyl glucoside esters and fatty acid gucamides. The esters listed above are preferably fatty acid esters.

Alkyl polyglucosides include alkyl polyglucosides with alkyl modifications selected from the chemical class of linear or branched, saturated or unsaturated fatty alcohols with a chain length of C12 to C22, preferable of C16 to C18; and preferably the alkyl polyglucoside has a glucoside polymerization degree of >1 and ≤ 2, more preferable of 1.0 to 1.7.

Examples of the sugar-based emulsifier can be any one or more selected from the group consisting of:

cetearyl glucoside (commercially available from Evonik with commercial name

Care CG 90) , coco-glucoside, such as MOTANOV ^TM S from SEPPIC (Coco-Glucoside (and) Coconut Alcohol) , and myristyl glucoside, such as MOTANOV ^TM 14 from SEPPIC (Myristyl Alcohol (and) Myristyl Glucoside) .

The amount of C20-36 fatty alcohol is 0.5-10 wt. %, for example, 0.5-9 wt. %, 0.5-8 wt. %, 0.5-7 wt. %, 0.5-6 wt. %, 0.5-5 wt. %, 0.5-4 wt. %, 0.5-3.5 wt. %, 0.8-9 wt. %, 0.8-8 wt. %, 0.8-7 wt. %, 0.8-6 wt. %, 0.8-5 wt. %, 0.8-4 wt. %, 0.8-3.5 wt. %, 1-9 wt. %, 1-8 wt. %, 1-7 wt. %, 1-6 wt. %, 1-5 wt. %, 1-4 wt. %, 1-3.5 wt. %, preferably 0.5-3 wt. %, 0.8-3 wt. %, or 1-3 wt. %, for example, 0.5-2.5 wt. %, 0.5-2 wt. %, 0.8-2.5 wt. %, 0.8-2 wt. %, 1-2.5 wt. %, 1-2 wt. %, based on the total weight of the emulsion.

Preferably the weight ratio of the C20-36 fatty alcohol to the emulsifier is in the range of from 2: 1 to 0.5: 1, more preferably of from 1.5: 1 to 1: 1 and most preferably of from 1.35: 1 to 1.1: 1.

In some embodiments, the O/W emulsion comprises by mass percentage of the following components:

1%-5%of an O/W emulsifier,

1%-10%of a C20-36 fatty alcohol,

5%-30%of a moisturizing fat,

60%-80%of water,

0.1%-5%of a preservative, and

1%-10%of glycerol.

The emulsions according to the invention can comprise e.g. at least one additional component selected from the group of

emollients,

emulsifiers,

thickeners/viscosity regulators/stabilizers,

UV light protection filters,

antioxidants,

hydrotropes (or polyols) ,

solids and fillers,

film formers,

pearlescence additives,

deodorant and antiperspirant active ingredients,

insect repellents,

self-tanning agents,

preservatives,

conditioners,

perfumes,

dyes,

odour absorbers,

cosmetic active ingredients,

care additives,

superfatting agents,

solvents.

Substances which can be used as exemplary representatives of the individual groups are known to the person skilled in the art and can be found for example in the German application DE 102008001788.4. This patent application is herewith incorporated as reference and thus forms part of the disclosure.

As regards further optional components and the amounts of these components used, reference is made expressly to the relevant handbooks known to the person skilled in the art, e.g. K. Schrader, “Grundlagen und Rezepturen der Kosmetika [Fundamentals and Formulations of Cosmetics] ” , 2nd edition, pages 329 to 341, Hüthig Buch Verlag Heidelberg.

The emulsion according to the invention preferably comprises free fatty acids or their salts, preferably long chained fatty acids, more preferably a mixture of C22 and C24 fatty acid, even more preferred as salt. The amount of fatty acid comprised in the emulsion of the instant invention is preferably in the range of 10 to 20 wt. %, wherein the weight percentages refer to the total emulsion. If the free fatty acid is comprised as a salt the weight percentages are calculated without the cation accounting for the weight.

For the preparation process of the emulsion according to the instant invention, due to the high melting point of C20-36 fatty alcohol (about 80-90 degrees Celsius) , it is necessary to add the melted C20-36 fatty alcohol to the oil phase to make it completely dissolved, and then carry out subsequent routine of O/W emulsion preparation process.

Therefore, according to the invention, compared with C16-18 fatty alcohols, C20-36 fatty alcohols have a reduced the viscosity building effect but can stabilize O/W emulsions, offer co-emulsifying capability and viscosity building effect.

Other advantages of the present invention would be apparent for a person skilled in the art upon reading the specification.

Brief Description of Drawings

Figure 1 shows the viscosity of the emulsions prepared in the Examples and Comparative Examples.

Detailed description of the invention

The invention is now described in detail by the following examples. The scope of the invention should not be limited to the embodiments of the examples.

The emulsion in the description was prepared according to the method as follows,

1) add ingredients of phase A according to the listed formulation into a beaker, heat the ingredients of phase A to 85℃,

2) add ingredients of phase B into another beaker, heat the ingredients of phase B to around 85℃,

3) mix the phase A and the phase B, and homogenize at a high speed with a homogenizer for 3 minutes,

4) add the ingredients of phase C and stir for 3 minutes, and

5) cool down with stirring, add the ingredients of phase Z (and phase D, if any) below 40℃, stir for a while until a uniform emulsion is obtained.

The viscosity of the prepared emulsions was measured with the measurement using Brookfield RVT, S93, 10rpm, 10s.

In the examples,

Care CG 90 was used as cetearyl glucoside, which is commercially available from Evonik Industries AG.

1-Eicosanol (C ₂₀H ₄₂O >95 wt. %) was used as C20 fatty alcohol, which is commercially available from Tokyo Chemical Industry.

1-Docosanol (C ₂₂H ₄₆O >98 wt. %) was used as C22 fatty alcohol, which is commercially available from Tokyo Chemical Industry.

1-Octacosanol (C ₂₈H ₅₈O >90 wt. %) was used as C28 fatty alcohol, which is commercially available from Ourchem (Sinopharm Chemical Reagent Co., Ltd. ) .

Triacontanol (C ₃₀H ₆₂O >90 wt. %) was used as C30 fatty alcohol, which is commercially available from Shanghai Aladdin Biochemical Technology Co., Ltd. (Shanghai, China) .

The policosanol commercially purchased from Huzhou Shengtao Biotech LLC (Zhejiang, China) was used as a mixed C20-C36 fatty alcohol. According to GC-MS measurement, the policosanol comprises C24-C34 fatty alcohols as main components, and it also comprises a small amount of C36 fatty alcohol.

Alkanol 1618 was used as cetearyl alcohol, which is commercially available from Evonik Industries AG.

PC was used as a preservative, which is commercially available from Evonik Dr. Straetmans GmbH.

NC MB was used as a O/W emulsifier, which is commercially available from Evonik Industries AG.

CG-SFT was used as a xanthan gum, which is commercially available from CP Kelco.

Examples 1-5

O/W emulsions using C20, C22, C28, C30 fatty alcohol and a policosanol respectively were prepared in Examples 1-5, according to the formulations as described in Table 1. In the formulation, cetearyl glucoside was used as a co-emulsifier.

Comparative Examples 1-4

O/W emulsions using C16, C18 and C16/C18 fatty alcohol respectively were prepared in Comparative Examples 1-3, and O/W emulsion without using any C16-C18 fatty alcohol were prepared in Comparative Example 4 ( “control” in Figure 1) , according to the formulations as described in Table 1.

The viscosity of the emulsions prepared in the Examples and Comparative Examples were tested and the results were also summarized in Table 1 below and Figure 1.

Table 1

CE*=Comparative Example

E**= Example

The test results of viscosity in the Table 1 and Figure 1 indicate a significant trend that the viscosity of the emulsion varies with the length of the carbon chain of the fatty alcohol. Particularly, emulsions with C20, C22, C28 and C30 fatty alcohol and policosanol have a lower viscosity than emulsions with C16-C18 fatty alcohol.

Example 6

An O/W emulsion with glycoside emulsifier was prepared according to the formulation of Table 2.

Table 2

Comparative Example 6

An O/W emulsion with glycoside emulsifier was prepared according to the formulation of Table 2. The formulation is the same as that of Example 6 except that a C16-18 fatty alcohol was used to replace the policosanol.

Example 7

An O/W emulsion with PEG emulsifier was prepared according to the formulation of Table 3.

Table 3

Comparative Example 7

An O/W emulsion with PEG emulsifier was prepared according to the formulation of Table 3. The formulation is the same as that of Example 7 except that the C16-18 fatty alcohol was used to replace the policosanol.

Example 8

An O/W emulsion with anion emulsifier was prepared according to the formulation of Table 4.

Table 4

Comparative Example 8

An O/W emulsion with anion emulsifier was prepared according to the formulation of Table 4. The formulation is the same as that of Example 8 except that the C16-18 fatty alcohol was used to replace the policosanol.

Example 9

An O/W emulsion with polyglyceride emulsifier was prepared according to the formulation of Table 5.

Table 5

Comparative Example 9

An O/W emulsion with polyglyceride emulsifier was prepared according to the formulation of Table 5. The formulation is the same as that of Example 9 except that the C16-18 fatty alcohol was used to replace the policosanol.

The viscosity of the emulsions prepared in the Examples 6-9 and Comparative Examples 6-9 were determined and the results were summarized in Table 6 below.

Table 6

Examples	Viscosity (cP)
Example 6	10738
Comparative Example 6	27400

Example 7	51589
Comparative Example 7	90581
Example 8	23275
Comparative Example 8	49905
Example 9	31300
Comparative Example 9	39800

As shown in Table 6, when cetearyl alcohol was replaced by policosanol, which is a mixed C24-C36 fatty alcohol, the viscosities of the different O/W emulsions were greatly reduced.

As used herein, terms such as “comprise (s) ” and the like as used herein are open terms meaning “including at least” unless otherwise specifically noted.

All references, tests, standards, documents, publications, etc. mentioned herein are incorporated herein by reference. Where a numerical limit or range is stated, the endpoints are included. Also, all values and subranges within a numerical limit or range are specifically included as if explicitly written out.

The above description is presented to enable a person skilled in the art to make and use the invention and is provided in the context of a particular application and its requirements. Various modifications to the preferred embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the invention. Thus, this invention is not intended to be limited to the embodiments shown but is to be accorded the widest scope consistent with the principles and features disclosed herein. In this regard, certain embodiments within the invention may not show every benefit of the invention, considered broadly.

Claims

Use of a C20-36 fatty alcohol to prepare an O/W emulsion with lower viscosity compared with the O/W emulsion wherein the C20-36 fatty alcohol is replaced by a C16-18 fatty alcohol.
The use of claim 1, wherein the C20-36 fatty alcohol has a carbon chain length of 20-35, 20-34, 20-33, 20-32, 20-31, 20-30, preferably 20-30, for example, 20-29, 20-28, more preferably 20-26, for example, 20-24, or 20-22.
The use of claim 1, wherein the amount of C20-36 fatty alcohol is 0.5-10 wt. %, for example, 0.5-9 wt. %, 1-9 wt. %, 1-8 wt. %, 1-7 wt. %, 1-6 wt. %, 1-5 wt. %, 1-4 wt. %, 1-3.5 wt. %, preferably 0.5-3 wt. %, 0.8-3 wt. %, or 1-3 wt. %, for example, 0.5-2.5 wt. %, 0.5-2 wt. %, 0.8-2.5 wt. %, 0.8-2 wt. %, 1-2.5 wt. %, 1-2 wt. %, based on the total weight of the emulsion.
The use of claim 1, wherein the O/W emulsion contains at least one emulsifier selected from polyglycerol ester emulsifiers, anion emulsifiers, PEG emulsifiers and sugar-based emulsifiers.
An O/W emulsion, which comprises

a) 0.5 wt. %-10 wt. %, preferably 1-3 wt. %of a C20-36 fatty alcohol, based on the total weight of the emulsion.
The emulsion of claim 5, wherein the emulsion comprises 1 wt. %-5 wt. %of an O/W emulsifier, based on the total weight of the emulsion.
The emulsion of claim 6, wherein the emulsifier is selected from polyglycerol ester emulsifiers, anion emulsifiers, PEG emulsifiers and sugar-based emulsifiers.
The emulsion of claim 5, wherein the emulsion comprises at least 90 wt. %, preferably at least 95 wt. %more preferably at least 95 wt. %C20-36 fatty alcohol with the weight percentages referring to all fatty alcohols comprised in the total emulsion.
The emulsion of claim 5, wherein the C20-36 fatty alcohol has a carbon chain length of 20-35, 20-34, 20-33, 20-32, 20-31, 20-30, preferably 20-30, for example, 20-29, 20-28, more preferably 20-26, for example, 20-24, or 20-22.
The emulsion of claim 5, wherein the C20-36 fatty alcohol is a mixture and the amount of C20-30 fatty alcohol is more than 30 wt. %, 40 wt. %, or 50 wt. %, preferably more than 60 wt. %, more than 70 wt. %, more preferably more than 80 wt. %, more than 90 wt. %, more than 95 wt. %, more than 99 wt. %in the C20-36 fatty alcohol.
The emulsion of claim 5, wherein the amount of C20-36 fatty alcohol is 0.5-9 wt. %, 0.5-8 wt. %, 0.5-7 wt. %, 0.5-6 wt. %, 0.5-5 wt. %, 0.5-4 wt. %, 0.5-3.5 wt. %, 0.8-9 wt. %, 0.8-8 wt. %, 0.8-7 wt. %, 0.8-6 wt. %, 0.8-5 wt. %, 0.8-4 wt. %, 0.8-3.5 wt. %, 1-9 wt. %, 1-8 wt. %, 1-7 wt. %, 1-6 wt. %, 1-5 wt. %, 1-4 wt. %, or 1-3.5 wt. %, preferably 0.5-3 wt. %, 0.8-3 wt. %, or 1-3 wt. %, for example, 0.5-2.5 wt. %, 0.5-2 wt. %, 0.8-2.5 wt. %, 0.8-2 wt. %, 1-2.5 wt. %, 1-2 wt. %, based on the total weight of the emulsion.
A method to produce an O/W emulsion with lower viscosity than an O/W emulsion with a C16-18 fatty alcohol, wherein the O/W emulsion is prepared using a C20-36 fatty alcohol, preferably to replace the C16-18 fatty alcohol.