Cosmetic wax composition

Abstract

[Problem] To provide a cosmetic wax composition that, when incorporated into cosmetics, can suppress changes in the gloss and application feel of cosmetics due to environmental changes. [Solution] A cosmetic wax composition containing two or more monoesters M represented by the following structural formula (1), wherein the two or more monoesters M include monoester MA, which has the highest content, and one or more monoesters MB, which have 4 or more carbon atoms in the molecule than monoester MA, and per 100 parts by mass of the wax composition, monoester M is 90 to 99 parts by mass, monoester MA is 50 to 98 parts by mass, and monoester MB is 1 to 15 parts by mass, and the melting point is 60 to 80°C. R1CO-O-R2(1) [In formula (1), R1CO represents a linear saturated acyl group having 16 to 34 carbon atoms, and R2 represents a linear alkyl group having 16 to 34 carbon atoms.] [Selected Figure] None

Description

[Technical Field]

[0001] This invention relates to a wax composition used in cosmetics. [Background technology]

[0002] Waxes, such as hydrocarbons and fatty acid esters that are solid at room temperature, are used to thicken or solidify cosmetics. Examples of cosmetics in which such waxes are suitably used include non-aqueous oil-based cosmetics such as lipsticks and cleansing balms, oil-in-water emulsion cosmetics such as hand creams and face creams, and water-in-oil emulsion cosmetics such as sunscreens. Improvements are being made to the appearance of these cosmetics, including gloss, and the feel during application, and consequently, the development of waxes is progressing rapidly.

[0003] For example, Patent Document 1 discloses a solid cosmetic composition that contains a non-polar wax, a polar wax, and a liquid oil in a specific mass ratio, and is characterized in that the penetration hardness of the mixture of the non-polar wax, polar wax, and liquid oil is lower than the penetration hardness of the mixture of only the non-polar wax and liquid oil, and it is stated that this solid cosmetic composition achieves both a smooth application feel and a matte finish.

[0004] Furthermore, Patent Document 2 discloses an oily gel composition containing a specific polyglycerin fatty acid ester and a plant wax, and describes that this oily gel composition is excellent in gel strength, high temperature stability, surface smoothness, and gloss, and is used in oily solid cosmetics.

[0005] In recent years, cosmetics have been rapidly gaining popularity in emerging countries. Countries classified as emerging countries often have much hotter and more humid environments, or colder and less humid environments, compared to developed countries. However, Patent Document 1 does not examine whether the desired appearance and application feel can be obtained even under high temperature and high humidity or low temperature and less humidity conditions. Furthermore, Patent Document 2 shows that an oily gel composition exhibits excellent high-temperature stability due to its high melting point and excellent gloss due to its high gloss, but it does not examine whether gloss and application feel are maintained under high temperature and high humidity or low temperature and less humidity conditions. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2023-62540 [Patent Document 2] Japanese Patent Publication No. 2024-115779 [Overview of the project] [Problems that the invention aims to solve]

[0007] The present invention aims to provide a wax composition for cosmetics that, when incorporated into cosmetics, can suppress changes in the glossiness and application feel of cosmetics due to changes in the environment. [Means for solving the problem]

[0008] The inventors of the present invention have discovered that by incorporating a specific wax composition into a cosmetic, it is possible to obtain a cosmetic that is less prone to changes in glossiness under various environmental conditions and less prone to changes in application feel due to changes in the usage environment, thereby completing the present invention.

[0009] In other words, the present invention is as follows: [1] A wax composition comprising two or more monoester M represented by the following structural formula (1), Of the two or more types of monoester M, the monoester M with the highest content is... Aand a monoester M having 4 or more carbon atoms in the molecule than the monoester M A including one or more kinds, B with respect to 100 parts by mass of the wax composition, the total content of the monoester M is 90 to 99 parts by mass, and the content of the monoester M A is 50 to 98 parts by mass, and the total content of the monoester M B is 1 to 15 parts by mass, a wax composition for cosmetics, wherein the melting point of the wax composition is 60°C to 80°C. R 1 CO-O-R 2 (1) 〔In the formula (1), R 1 CO represents a linear saturated acyl group having 16 to 34 carbon atoms, and R 2 represents a linear alkyl group having 16 to 34 carbon atoms.〕

[0010] [2] When the number of carbon atoms of the R A CO in the monoester M is C1 and the number of carbon atoms of the R 1 is C2, the wax composition for cosmetics according to [1], which satisfies the following formula (2). 2 C1≠C2(2)

Advantages of the Invention

[0011] By incorporating the wax composition of the present invention into cosmetics, it is possible to suppress changes in the glossiness of cosmetics in a low-temperature and low-humidity environment and a high-temperature and high-humidity environment, and further reduce the difference between the application feeling of cosmetics in a normal-temperature and normal-humidity environment and the application feeling of cosmetics in a low-temperature and low-humidity environment and a high-temperature and high-humidity environment.

Embodiments for Carrying Out the Invention

[0012]

[0013] The wax composition of the present invention is typically used as a solidifying agent in oil-based cosmetics. Cosmetics containing the wax composition of the present invention do not show significant changes in gloss under a variety of environmental conditions, including low temperature and low humidity environments and high temperature and high humidity environments. By including the wax composition of the present invention, the difference in application feel between normal temperature and humidity environments and low temperature and low humidity environments is reduced, and further, the difference in application feel between normal temperature and humidity environments and high temperature and high humidity environments is also reduced, meaning that the difference in application feel due to differences in usage environment is small.

[0013] The embodiments of the present invention will be described below, but the present invention is not limited to the embodiments described herein and can be modified in various ways without departing from the spirit of the invention. The "cosmetic wax composition" of the present invention may sometimes be simply referred to as "wax composition." Furthermore, in this invention, the "feel of application" of a cosmetic refers to the sensation a person feels when applying the cosmetic to their skin. Specific examples include softness, non-stickiness, and ease of application. Furthermore, in this invention, a numerical range defined using the symbol "~" includes the numerical values ​​at both ends (upper and lower limits) of "~". For example, "2~10" represents the range of 2 to 10. Furthermore, within the numerical range described in the present invention, the upper or lower limit of that numerical range can be replaced with the values ​​shown in the examples or values ​​uniquely derived from the examples.

[0014] [Monoester M] The monoester M contained in the wax composition of the present invention is a compound represented by the following structural formula (1). R 1 CO-OR 2 (1) [In formula (1), R 1 CO represents a straight-chain saturated acyl group with 16 to 34 carbon atoms, R 2 This represents a linear alkyl group with 16 to 34 carbon atoms.

[0015] R in the above structural formula (1) 1The linear saturated acyl group represented by CO has 16 to 34 carbon atoms, and R in the above structural formula (1) 2 The linear saturated alkyl group represented by has 16 to 34 carbon atoms, and as a result, the wax composition of the present invention has good affinity with base oils and can effectively suppress changes in the gloss and application feel of cosmetics due to environmental changes. Furthermore, because the wax composition of the present invention has good affinity with base oils, it can be suitably used as a solidifying agent for base oils. From this viewpoint, in the monoester M used in the present invention, R 1 The number of carbon atoms in the linear saturated acyl group represented by CO is preferably 18 to 32, more preferably 18 to 26. 2 The number of carbon atoms in the linear saturated alkyl group represented by is preferably 18 to 32, more preferably 18 to 26.

[0016] In the present invention, the above monoester M is defined as R in the above structural formula (1). 1 The number of carbon atoms in the straight-chain saturated acyl group represented by CO is denoted as "C1", and in the above structural formula (1), R 2 The number of carbon atoms in a linear saturated alkyl group represented by is sometimes denoted as "C2". Also, the structure of the above monoester M is sometimes denoted as "CC1-CC2". For example, stearyl stearate is denoted as "C18-C18".

[0017] Examples of the above monoester M include stearyl stearate "C18-C18" and behenyl behenate "C22-C22", R 1 The carbon number C1 and R of CO 2 Compounds with the same number of carbon atoms (C2), such as arachidyl behenate "C22-C20" and triacontanyl lignocerate "C24-C30", 1 The carbon number C1 and R of CO 2 Examples include compounds with different carbon atoms (C2). In the present invention, any of these can be used, but from the viewpoint of suppressing changes in the glossiness and application feel of the cosmetic due to environmental changes, the above monoester M is R 1 The carbon number C1 and R of CO 2Compounds with different carbon number C2s are preferably used. Also, from the same viewpoint as above, the monoester M used in the present invention preferably has a difference between C1 and C2 (|C1-C2|) of 1 or more, more preferably 2 or more, with an upper limit of preferably 10 or less, more preferably 6 or less, and even more preferably 4 or less.

[0018] The synthesis method for the above monoester M can be any known method and is not particularly limited. Examples include the dehydration condensation reaction of a linear saturated fatty acid having 16 to 34 carbon atoms and a linear saturated aliphatic alcohol having 16 to 34 carbon atoms, and the reaction of a linear saturated fatty acid chloride having 16 to 34 carbon atoms and a linear saturated aliphatic alcohol having 16 to 34 carbon atoms. Catalysts may be used in these reactions. Furthermore, the above monoester M can also be obtained by extraction from natural waxes such as candelilla wax, carnauba wax, rice wax, or sunflower wax.

[0019] [Wax composition] The wax composition of the present invention contains the most abundant monoester M as the above monoester M. A , and the number of carbon atoms in the molecule of the monoester M A Monoester M, which is 4 or more more than that. B It contains one or more types, and the total content of the above monoester M is 90 to 99 parts by mass per 100 parts by mass of the wax composition, and the above monoester M A The content is 50 to 98 parts by mass, and the above monoester M BThe total content is 1 to 15 parts by mass. Because the wax composition of the present invention has such a composition, it is less susceptible to changes in crystallinity due to changes in the environment. As a result, cosmetics containing the wax composition of the present invention have suppressed changes in gloss due to changes in the environment, and further suppressed changes in the feel of application due to changes in the environment in which the cosmetics are used. In addition, by including a small amount of material other than the monoester M in the wax composition of the present invention, changes in crystallinity due to changes in the environment become even less likely to occur. As a result, cosmetics containing the wax composition of the present invention have even more suppressed changes in gloss and feel due to changes in the environment.

[0020] The wax composition of the present invention has a total content of 90 to 99 parts by mass of the monoester M per 100 parts by mass of the wax composition. The sufficiently high total content of the monoester M makes it suitable for use as a solidifying agent for solidifying base oils, and it can effectively suppress changes in the gloss and application feel of cosmetics due to environmental changes. From this viewpoint, the total content of the monoester M per 100 parts by mass of the wax composition is preferably 92 to 99 parts by mass, more preferably 94 to 99 parts by mass.

[0021] The wax composition of the present invention uses the monoester M that has the highest content among the monoester M contained in the wax composition. A And the number of carbon atoms in the molecule is the same as the above monoester M A Monoester M, which is 4 or more more than that. B It contains one or more of the above monoester M. That is, the wax composition of the present invention contains two or more of the above monoester M. The monoester M with the highest content is A There is only one type. The above monoester M A The content is 50 to 98 parts by mass per 100 parts by mass of the wax composition. This makes it possible to easily set the melting point of the wax composition of the present invention to 60°C to 80°C, and also suppresses changes in gloss and application feel of cosmetics containing the wax composition of the present invention due to changes in the environment. From this viewpoint, the above monoester M AThe content of is preferably 55 parts by mass or more, more preferably 60 parts by mass or more, and even more preferably 80 parts by mass or more, as a lower limit, while the upper limit is preferably 98 parts by mass or less, more preferably 96 parts by mass or less, and even more preferably 95 parts by mass or less.

[0022] The most abundant monoester M A This is a compound corresponding to the above monoester M, and is not particularly limited, but from the viewpoint of obtaining the effects of the present invention more significantly, R in the above structural formula (1) 1 The number of carbon atoms in CO is C1, R 2 When the number of carbon atoms is C2, it is preferable that the following formula (2) is satisfied. C1 ≠ C2 (2)

[0023] The above monoester M A When the above formula (2) is satisfied, that is, when the linear saturated acyl group R 1 The number of carbon atoms in CO and the linear saturated alkyl group R 2 When the number of carbon atoms differs, the crystal formation of the wax composition of the present invention in the base oil is moderately suppressed, making it difficult for coarse crystals to form. Therefore, in cosmetics containing the wax composition of the present invention, the effect of suppressing changes in gloss and application feel due to environmental changes is easily exhibited.

[0024] On the other hand, from the viewpoint of ensuring a certain level of crystallinity in the wax composition of the present invention, the above monoester M A It is preferable that C1 and C2 further satisfy the following formula (3). 2 ≤ |C1 - C2| ≤ 4 (3) |C1-C2| in formula (3) above is R in structural formula (1) above. 1 The number of carbon atoms in the straight-chain saturated acyl group represented by CO, and R in the above structural formula (1) 2 This is the difference from the number of carbon atoms of the linear saturated alkyl group represented by the above monoester M. A When the above formula (3) is satisfied, the wax composition of the present invention is likely to maintain appropriate crystallinity even when the environment changes, and therefore, in cosmetics containing the wax composition of the present invention, the effect of suppressing changes in gloss and application feel due to environmental changes is likely to be exhibited.

[0025] Furthermore, from the viewpoint of setting the melting point of the wax composition to 60°C to 80°C, the above monoester M A The number of carbon atoms is preferably 38 or more at the lower limit, more preferably 40 or more, and even more preferably 42 or more, and is preferably 54 or less at the upper limit, more preferably 48 or less, and even more preferably 44 or less. The above monoester M A Preferred examples include, for example, stearyl behenate "C22-C18", arachidyl behenate "C22-C20", behenyl stearate "C18-C22", behenyl arachidate "C20-C22", behenyl behenate "C22-C22", arachidyl stearate "C18-C20", and behenyl palmitate "C16-C22", among which stearyl behenate "C22-C18", arachidyl behenate "C22-C20", behenyl stearate "C18-C22", and behenyl arachidate "C20-C22".

[0026] The wax composition of the present invention has a number of carbon atoms in the molecule that is the above monoester M A Monoester M, which is 4 or more more than that. B It contains one or more of these. As a result, the wax composition of the present invention is less susceptible to changes in crystallinity due to environmental changes, and therefore, in cosmetics containing the wax composition of the present invention, changes in gloss and application feel due to environmental changes are suppressed. The above monoester M B When comparing the number of carbon atoms in one molecule, the above monoester M A The compound represented by the above structural formula (1) has 4 or more carbon atoms than the above monoester M. A The number of carbon atoms and the above monoester M B The difference from the carbon number should be 4 or more, but from the viewpoint of suppressing changes in the glossiness and application feel of the cosmetic due to environmental changes, it is preferably 4 to 20, more preferably 4 to 18, even more preferably 4 to 16, and even more preferably 4 to 14.

[0027] The wax composition of the present invention contains the above monoester M B The number of types is not particularly limited, and may be one or more. For example, from the standpoint of ease of manufacture, it may be between 1 and 30 types.

[0028] The above monoester M B The above monoester M A The above monoester M is selected appropriately depending on the number of carbon atoms and is not particularly limited, but in a cosmetic composition containing the wax composition of the present invention, the effect of suppressing changes in gloss and application feel due to environmental changes is easily exhibited. B Preferably, it contains at least one selected from the group consisting of behenyl behenate "C22-C22", behenyl lignocerate "C24-C22", lignoceryl behenate "C22-C24", octacosanyl behenate "C22-C28", triacontanyl behenate "C22-C30", octacosanyl lignocerate "C24-C28", and triacontanyl lignocerate "C24-C30". Furthermore, the wax composition of the present invention contains monoester M B When incorporating it, a chemically synthesized monoester M B It may also be added, or monoester M B Natural waxes with as the main component, such as carnauba wax, rice wax, sunflower wax, etc., may be added, or monoester M A and monoester M B A mixture containing the following may be added.

[0029] The above monoester M B The total content is 1 to 15 parts by mass per 100 parts by mass of the wax composition. The above monoester M B Because the total content of is within the above range, the wax composition of the present invention is less susceptible to changes in crystallinity due to environmental changes, and therefore, in cosmetics containing the wax composition of the present invention, changes in gloss and application feel due to environmental changes can be suppressed. From this viewpoint, the above monoester M BThe total content of is preferably 2 parts by mass or more, 10 parts by mass or less, and more preferably 5 parts by mass or less, per 100 parts by mass of the wax composition.

[0030] The wax composition of the present invention has a number of carbon atoms in the molecule that is the above monoester M A Compared to monoester M, it is the same, less, or 1-3 times more. C It may further contain the above monoester M C The total content of is preferably 30 parts by mass or less, more preferably 10 parts by mass or less, and even more preferably 5 parts by mass or less, per 100 parts by mass of the wax composition, from the viewpoint of not impairing the effects of the present invention. The wax composition of the present invention is the above monoester M C It is not necessary to include the above monoester M, but from the viewpoint of ease of manufacture, C The total content may be 1 part by mass or more. The composition of the wax composition and the content of each component can be confirmed, for example, by gas chromatography (GC). Furthermore, in the present invention, the total content of monoester M per 100 parts by mass of the wax composition, and monoester M A Content of monoester M B The total content, and monoester M C The total content of [the substance] shall be an integer value rounded to the first decimal place.

[0031] In a cosmetic composition containing the wax composition of the present invention, the wax composition of the present invention preferably has a melting point of 60 to 80°C, and more preferably 65 to 75°C, as determined by differential scanning calorimetry (DSC), in order to improve the feel when applied and to further suppress changes in the feel when applied due to changes in the usage environment, and to improve the gloss.

[0032] Furthermore, the wax composition of the present invention preferably has a difference (ΔTc) between the crystallization start temperature (Tca) and the crystallization end temperature (Tcb), determined by differential scanning calorimetry (DSC), of 10 to 25°C. The above ΔTc represents the crystallinity of the wax composition. When the above ΔTc is within this range, that is, when the wax composition exhibits a specific crystallinity, the wax composition of the present invention is likely to form crystals uniformly in the base oil. As a result, in cosmetics containing the wax composition of the present invention, changes in application feel and gloss due to environmental changes can be further suppressed. From this viewpoint, the above ΔTc is more preferably 10 to 20°C, and even more preferably 10 to 15°C.

[0033] The wax composition of the present invention contains 1 to 10 parts by mass of component X, which is different from the monoester M mentioned above, per 100 parts by mass of the wax composition. This makes it possible to further suppress changes in gloss and application feel due to environmental changes in cosmetics containing the wax composition of the present invention. From this viewpoint, the content of component X is preferably 1 to 5 parts by mass per 100 parts by mass of the wax composition. The above component X preferably contains at least one selected from linear saturated fatty acids having 16 to 34 carbon atoms and linear saturated aliphatic alcohols having 16 to 34 carbon atoms, and more preferably contains at least one selected from linear saturated fatty acids and linear saturated aliphatic alcohols that can serve as raw materials for monoester M contained in the wax composition. The total content of such linear saturated fatty acids and linear saturated aliphatic alcohols is preferably 90% by mass or more, more preferably 95% by mass or more, and even more preferably 99% by mass or more, based on 100% by mass of the total amount of component X. Furthermore, the total content of linear saturated fatty acids having 16 to 34 carbon atoms and linear saturated aliphatic alcohols having 16 to 34 carbon atoms is preferably 1 to 10 parts by mass, and more preferably 1 to 5 parts by mass, per 100 parts by mass of the wax composition. Furthermore, the linear saturated fatty acids and linear saturated aliphatic alcohols included as component X may be unreacted raw materials or impurities derived from the raw materials that remain in the wax composition, or they may be intentionally added.

[0034] The acid value of the wax composition of the present invention is preferably 0.1 to 5.0 mg KOH / g, more preferably 0.1 to 1.0 mg KOH / g, and even more preferably 0.1 to 0.5 mg KOH / g. When the acid value of the wax composition is within the above range, the changes in gloss and application feel due to environmental changes can be further reduced in a cosmetic composition containing the wax composition of the present invention. Furthermore, the hydroxyl value of the wax composition of the present invention is preferably 0.1 to 10.0 mg KOH / g, more preferably 0.5 to 5.0 mg KOH / g, and even more preferably 1.0 to 3.0 mg KOH / g. When the hydroxyl value of the wax composition is within the above range, changes in gloss and application feel due to environmental changes can be further suppressed in cosmetics containing the wax composition of the present invention.

[0035] Since the wax composition of the present invention is typically used by being melted and mixed with a base oil or the like during the manufacture of cosmetics, the wax composition of the present invention before being added to cosmetics may be a composition obtained by pre-melting and mixing uniformly, or it may be a composition obtained by physically mixing finely ground materials of each component constituting the wax composition of the present invention.

[0036] The method for producing the wax composition of the present invention is not particularly limited, as long as it is a method that yields the wax composition of the present invention as described above. For example, a method can be given that includes the steps of preparing a plurality of types of monoester M and mixing these plurality of types of monoester M. In this method, when mixing the plurality of types of monoester M, a component X different from monoester M may be further mixed. Furthermore, the monoester M used in the production of the wax composition may be a single compound, or a monoester mixture containing monoester M as the main component may be used. In other words, the above method may include a step of preparing several types of monoester mixtures and a step of mixing these several types of monoester mixtures. The above monoester mixture contains monoester M as the main component, and may contain a small amount of component X, which is at least one selected from fatty acids and aliphatic alcohols that are raw materials for monoester M, and may also contain monoester M different from the main component monoester M. In order to easily obtain the wax composition of the present invention, the above monoester mixture preferably contains 90% by mass or more of monoester M per 100% by mass of the monoester mixture, more preferably contains 90-99% by mass of monoester M with the remainder being impurities (component X) derived from the raw materials, and even more preferably contains 94-98% by mass of monoester M with the remainder being impurities (component X) derived from the raw materials. Furthermore, in the above monoester mixture, the content of the main component monoester M is preferably 90% by mass or more, and may be 95-99% by mass, per 100% by mass of the total content of monoester M contained in the monoester mixture (including monoester M other than the main component). Such monoester mixtures are preferably used from the viewpoint of ease of manufacture of the wax composition of the present invention. For example, the monoester mixture can be obtained by performing a purification treatment to achieve the desired purity in the above-described method for synthesizing monoester M. Also, when obtaining monoester M by extraction from natural wax as described above, the monoester mixture can be obtained by repeatedly extracting with an organic solvent to achieve the desired purity, and then recrystallizing. Alternatively, the monoester mixture can be obtained by melt-mixing monoester M and component X. Commercially available monoesters with a purity of less than 100% may also be used as the monoester mixture. When mixing multiple types of monoester M or a monoester mixture, the formulation should be such that the total content of monoester M is 90 to 99 parts by mass per 100 parts by mass of the resulting wax composition. A The content of the above monoester M is 50 to 98 parts by mass. BThe total content should be adjusted to 1 to 15 parts by mass. For example, when obtaining the wax composition of the present invention by mixing multiple types of monoester mixtures, the total amount of monoester M should be adjusted to 100 parts by mass of the monoester mixture. A The amount of one type of monoester mixture containing as the main component is 60 to 99 parts by mass, monoester M B The wax composition of the present invention can be easily obtained by using a total amount of 1 to 15 parts by mass of one or more monoester mixtures containing as the main component. Furthermore, the mixing of multiple types of monoester M or monoester mixtures may be done by melt mixing, as described above, or by physical mixing of finely ground materials. Furthermore, the melting point of the wax composition tends to be higher as the content of monoester M with a large number of carbon atoms increases, and the most abundant monoester M A It is greatly affected by the number of carbon atoms. Therefore, monoester M is used so that the melting point of the resulting wax composition is 60°C to 80°C. A It is preferable to adjust the number and content of carbon atoms.

[0037] In addition, as a method for producing the wax composition of the present invention, for example, the total content of monoester M is 90 to 99 parts by mass per 100 parts by mass of the wax composition, and the above monoester M A The content of the above monoester M is 50 to 98 parts by mass. B Another method involves adjusting the composition of the raw materials, fatty acids and aliphatic alcohols, so that the total content is 1 to 15 parts by mass, and the melting point of the wax composition is 60°C to 80°C, before carrying out the esterification reaction.

[0038] The use of the wax composition of the present invention in cosmetics is not particularly limited, and it can be used, for example, in solid or creamy oil-based cosmetics, or emulsified cosmetics. Since the effects of the present invention are easily obtained, the wax composition of the present invention is preferably used in oil-based cosmetics, and more preferably in oil-based solid cosmetics such as lip cosmetics and cleansing balms. In other words, the wax composition of the present invention is preferably used as a wax for oil-based cosmetics, and more preferably as a wax for oil-based solid cosmetics.

[0039] There are no particular limitations on the method for producing a cosmetic product containing the wax composition of the present invention, and it can be produced by known methods. Examples of production methods are shown below, but are not limited thereto. For example, first, the wax composition of the present invention is heated and melted. Base oil and other components are added to the resulting solution. The mixture thus obtained is filled into a container and, if necessary, molded to obtain a cosmetic product containing the wax composition of the present invention.

[0040] The amount of the wax composition of the present invention added to the cosmetic is not particularly limited, but in order to easily obtain the effects of the present invention, the mass ratio of the base oil to the wax composition of the present invention (base oil:wax composition) is preferably in the range of 97:3 to 70:30, and more preferably in the range of 95:5 to 80:20.

[0041] Furthermore, the wax composition of the present invention is preferably used by adding it to a base oil containing at least one selected from hydrocarbon oils and ester oils. This makes it easier to obtain the effects of the wax composition of the present invention. Examples of hydrocarbon oils include straight-chain alkanes such as decane, dodecane, and tetradecane, and branched alkanes such as hydrogenated polyisobutene and squalane. Examples of ester oils include vegetable oils such as olive oil, as well as synthetic oils such as tri(caprylic / caprin), cetyl ethylhexanoate, hexyl laurate, polyglycerin isostearate, and medium-chain triglyceride. [Examples]

[0042] Hereinafter, the present invention will be described more specifically with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples. Note that parts and % are based on mass unless otherwise specified.

[0043] Hereinafter, the acid value was measured in accordance with JOCS (Japan Oil Chemists' Society) 2.3.1-1996, and the hydroxyl value was measured in accordance with JOCS (Japan Oil Chemists' Society) 2.3.6.2-1996. Also, the conditions for gas chromatography (GC) were as follows. <GC Conditions> Gas chromatograph: Nexis GC-2030 manufactured by Shimadzu Corporation Column: MXT (registered trademark)-1HT Sim Dist manufactured by RESTEK Column temperature: The temperature was raised from an initial temperature of 100°C to 430°C at a rate of 10°C / min and held at 430°C for 10 minutes. Injection temperature: 430°C Detection temperature: 430°C

[0044] <Synthesis Example> Using the raw material fatty acids and raw material aliphatic alcohols shown in Table 1, monoester mixtures M-1 to M-10 shown in Table 2 were obtained by the method shown in the following Synthesis Example. The raw material fatty acids shown in Table 1 contain a plurality of types of linear saturated fatty acids with different carbon numbers. In the fatty acids shown in Table 1, C16, C18, C20, C22, and C24 represent the carbon numbers of the linear saturated fatty acids, respectively, and correspond to the carbon number C1 of R 1 CO in the above structural formula (1). Table 1 shows the mass ratio (mass %) of the linear saturated fatty acids constituting each raw material fatty acid. Each raw material aliphatic alcohol shown in Table 1 contains a plurality of types of linear saturated aliphatic alcohols with different carbon numbers. In the aliphatic alcohols shown in Table 1, C16, C18, C20, C22, C24, C28, C30, and C32 represent the carbon numbers of the linear saturated aliphatic alcohols, respectively, and correspond to the carbon number C1 of R 2This corresponds to the number of carbon atoms C2. Table 1 shows the mass percentage (mass%) of the linear saturated aliphatic alcohols that make up each raw material aliphatic alcohol.

[0045] [Table 1]

[0046] (Synthesis Example 1) Synthesis of Monoester Mixture M-1 In a 300 mL four-necked flask equipped with a thermometer, nitrogen inlet tube, stirring blade, and condenser, 120.0 g (0.41 mol) of fatty acid FA-1 and 139.4 g (0.40 mol) of aliphatic alcohol AL-1 were added and reacted at 220 °C under a nitrogen stream. The resulting crude ester product was 252.5 g with an acid value of 5.0 mg KOH / g. To the crude ester product, 70 g of toluene and 15 g of 2-propanol were added, and a 10% by mass potassium hydroxide aqueous solution containing an amount equivalent to 2.0 times the residual acid value of the crude ester product was further added. The mixture was stirred at 70°C for 30 minutes. After that, it was allowed to stand for 30 minutes to separate and remove the aqueous layer (lower layer). The mixture was washed with water four times until the pH of the wastewater became neutral. The solvent in the remaining ester layer was removed by distillation under reduced pressure of 1 kPa at 180°C, and the mixture was filtered to obtain 230.1 g of monoester mixture M-1.

[0047] (Synthesis Example 2) Synthesis of Monoester Mixture M-2 To 10.0 g of the monoester mixture M-1 obtained in Synthesis Example 1, 48 mg of FA-1 was added and melt-mixed at 100°C to obtain monoester mixture M-2.

[0048] (Synthesis Example 3) Synthesis of Monoester Mixture M-3 To 10.0 g of the monoester mixture M-1 obtained in Synthesis Example 1, 49 mg of FA-1 and 150 mg of AL-1 were added, and the mixture was melt-mixed at 100°C to obtain monoester mixture M-3.

[0049] (Synthesis Example 4) Synthesis of Monoester Mixture M-4 Monoester mixture M-4 was obtained in the same manner as in Synthesis Example 1, except that the same molar amount of FA-2 was used instead of FA-1.

[0050] (Synthesis Example 5) Synthesis of Monoester Mixture M-5 Monoester mixture M-5 was obtained in the same manner as in Synthesis Example 1, except that the same molar amount of FA-2 was used instead of FA-1, and the same molar amount of AL-2 was used instead of AL-1.

[0051] (Synthesis Example 6) Synthesis of Monoester Mixture M-6 Monoester mixture M-6 was obtained in the same manner as in Synthesis Example 1, except that the same molar amount of FA-4 was used instead of FA-1, and the same molar amount of AL-2 was used instead of AL-1.

[0052] (Synthesis Example 7) Synthesis of Monoester Mixture M-7 Monoester mixture M-7 was obtained in the same manner as in Synthesis Example 1, except that the same molar amount of AL-2 was used instead of AL-1.

[0053] (Synthesis Example 8) Synthesis of Monoester Mixture M-8 Monoester mixture M-8 was obtained in the same manner as in Synthesis Example 1, except that the same molar amount of FA-3 was used instead of FA-1, and the same molar amount of AL-3 was used instead of AL-1.

[0054] (Synthesis Example 9) Synthesis of Monoester Mixture M-9 Monoester mixture M-9 was obtained in the same manner as in Synthesis Example 1, except that the same molar amount of FA-4 was used instead of FA-1.

[0055] (Synthesis Example 10) Synthesis of Monoester Mixture M-10 10.0 g of monoester mixture M-1 obtained in Synthesis Example 1 was dissolved at 80°C in a mixture of 90 g of toluene and 10 g of isopropyl alcohol. After standing and cooling, the precipitate was collected by filtration. The same procedure was repeated five times to obtain 2 g of monoester mixture M-10.

[0056] Table 2 below shows the raw material fatty acids and raw material alcohols used in the synthesis of the monoester mixture, the structure of the main component monoester M (main component M) of the obtained monoester mixture, the acid value and hydroxyl value of the monoester mixture, the total content of monoester M (M purity (mass%)) when the monoester mixture (including impurities) is set to 100% by mass, and the content of the most abundant monoester M (main component purity (mass%)) when the total content of monoester M in the monoester mixture (including monoester M other than the main component) is set to 100% by mass. The total content of monoester M in the monoester mixture (M purity) was calculated by determining the fatty acid content (mass%) and aliphatic alcohol content (mass%) from the acid value and hydroxyl value of the monoester mixture, and then subtracting the sum of these values ​​from the total amount of the monoester mixture (100 mass%). The content of the most abundant monoester M (main component purity) was determined by calculating the content (mass%) of each monoester M when the total content of monoester M was set to 100 mass%, based on the ratio of peak areas of the GC chart obtained by gas chromatography (GC) under the above GC conditions and the total content of monoester M (M purity), and then identifying the maximum amount among them.

[0057] [Table 2]

[0058] <Preparation of Wax Composition> According to Table 3, the above monoester mixtures M-1 to M-10 or fatty acid FA-1 were weighed out to a total of 20g and placed on an aluminum dish. By heating to 120°C, the monoester M and other components X were completely dissolved. After that, these were mixed until homogeneous and cooled and solidified to obtain wax compositions W-1 to W-19.

[0059] Table 3 shows the mass ratios (mass %) of the monoester mixtures M-1 to M-10 and the fatty acid FA-1 used in the preparation of each wax composition. This corresponds to the contents (parts by mass) of the monoester mixtures M-1 to M-10 and the fatty acid FA-1 with respect to 100 parts by mass of the wax composition.

[0060] Table 4 shows the compositions and physical properties of each of the wax compositions W-1 to W-19. As the composition of the wax composition, the total content of the monoester M, the monoester M having the highest content among the various monoesters M contained in the wax composition A regarding the structure, content, and difference between C1 and C2 (|C1 - C2|), and the monoester M A and the total content of the monoester M having 4 or more carbon atoms more in the molecule than the monoester M B are shown.

[0061] Note that the monoester M is a single compound represented by the above structural formula (1). The structure and content of each monoester M contained in the wax composition, and the component X other than the monoester M contained in the wax composition were specified by gas chromatography (GC) under the above GC conditions. The total content of the monoester M, the content of the monoester M A and the total content of the monoester M B shown in Table 4 are the contents (parts by mass) when the entire wax composition is 100 parts by mass.

[0062] In addition to the monoester M, the wax compositions W-1 to W-13 and W-15 to W-19 contained at least one selected from linear saturated fatty acids having 16 to 34 carbon atoms and linear saturated aliphatic alcohols having 16 to 34 carbon atoms, which are derived from any of the raw materials of the monoester mixtures M-1 to M-10 used in the preparation of the wax composition, as a component X different from the monoester M. The wax composition W-13 further contained the separately added fatty acid FA-1.

[0063] Table 4 shows the physical properties of the wax composition, including the melting point of the wax composition determined by DSC, the difference between the crystallization start temperature (Tca) and the crystallization end temperature (Tcb) of the wax composition determined by DSC (ΔTc), and the acid value and hydroxyl value of the wax composition. DSC was performed using a differential scanning calorimeter (DSC7000, manufactured by Hitachi High-Tech Science Corporation). The analysis of the DSC measurement results was performed using the standard analysis software included with the DSC7000. The specific procedure for DSC was as follows:

[0064] To determine the melting point of the wax composition, a DSC (Dynamic Stem Cell) was first performed by weighing 10 mg of the sample into an aluminum sample pan. The weighed sample was heated to 200°C at a rate of 10°C per minute in a measurement folder into which nitrogen was blown at a flow rate of 60 ml per minute, and then cooled to 30°C at a rate of 2°C per minute to ensure a uniform thermal history of the sample. Subsequently, the sample was heated from 30°C to 200°C at a rate of 10°C per minute to obtain a DSC curve during cooling. The obtained DSC curve showed an endothermic peak during melting when the sample was heated. The temperature of the endothermic peak in the DSC curve was defined as the melting point of the sample. If two or more endothermic peaks were observed, the temperature of the peak showing the largest endothermic value was defined as the melting point.

[0065] To determine the crystallization start temperature (Tca) and crystallization end temperature (Tcb) of a wax composition, a 10 mg sample was first weighed into an aluminum sample pan. The weighed sample was heated to 200°C at a rate of 10°C per minute in a measurement folder into which nitrogen was blown at a flow rate of 60 ml per minute, and then held at 200°C for 1 minute to ensure uniform thermal history between samples. Subsequently, the sample was cooled from 200°C to 30°C at a rate of 10°C per minute to obtain a DSC curve during cooling. The obtained DSC curve showed an exothermic peak (crystallization peak) when the sample was cooled. From the exothermic peak (crystallization peak) of the DSC curve, the extracorporeal crystallization start temperature and extracorporeal crystallization end temperature were determined and defined as the crystallization start temperature (Tca) and crystallization end temperature (Tcb), respectively, and the difference between the crystallization start temperature (Tca) and the crystallization end temperature (Tcb) (ΔTc) was calculated. The extrapolation start temperature and extrapolation end temperature were determined from the DSC curve in accordance with JIS K 7121 as follows. Extrapolation crystallization initiation temperature: This temperature was defined as the temperature at the intersection of a straight line extending the high-temperature baseline toward the low-temperature side and a tangent line drawn at the point where the slope of the high-temperature side curve of the crystallization peak is maximum. Extracorporeal crystallization termination temperature: This temperature was defined as the temperature at the intersection of a straight line extending the baseline on the low-temperature side towards the high-temperature side and a tangent line drawn at the point where the slope of the crystallization peak curve on the low-temperature side is maximum.

[0066] [Table 3]

[0067] [Table 4]

[0068] The wax compositions W-1 to W-12 shown in Tables 3 and 4 contain two or more monoester M represented by the above structural formula (1), with the most abundant monoester M being... A And, the number of carbon atoms in the molecule is the same as the monoester M AMore than 4 monoester M B is included, and based on 100 parts by mass of the wax composition, the total content of monoester M is 90 to 99 parts by mass, and the content of monoester M A is 50 to 98 parts by mass, and the total content of monoester M B is 1 to 15 parts by mass, and the melting point of the wax composition is 60°C to 80°C. This was the wax composition of the present invention. On the other hand, the wax compositions W-13 to W-19 were not the wax compositions of the present invention in the following points. In the wax composition W-13, the total content of monoester M was less than 90 parts by mass based on 100 parts by mass of the wax composition. In the wax composition W-14, the total content of monoester M exceeded 99 parts by mass based on 100 parts by mass of the wax composition. In the wax composition W-15, the content of monoester M A was less than 50 parts by mass. In the wax composition W-16, the total content of monoester M B was less than 1 part by mass. In the wax compositions W-17 and W-18, the total content of monoester M B exceeded 15 parts by mass based on 100 parts by mass of the wax composition. The wax composition W-19 had a melting point of less than 60°C.

[0069] <Examples 1 to 16 and Comparative Examples 1 to <7>: Preparation of Model Samples> According to Table 5, the wax compositions W-1 to W-19 were selected and mixed with the base oil. The obtained mixture was melt-mixed at 100°C on a hot plate in an aluminum pan and then allowed to cool at room temperature for 30 minutes to obtain model samples O-1 to O-23 of the oily solid cosmetic. Note that "Pearl Rim EX" shown in Table 5 is hydrogenated polyisobutene (product name: Pearl Rim (registered trademark) EX) manufactured by NOF Corporation. "Panacetate 810S" is medium-chain fatty acid triglyceride (product name: Panacetate (registered trademark) 810S) manufactured by NOF Corporation.

[0070] [Evaluation of gloss stability] For the obtained model samples, the gloss value was measured in 10 areas using a HORIBA IG-320 gloss checker under normal temperature and humidity conditions of 25°C and 50% relative humidity, with an incident angle of 60°C. The average value was then defined as the gloss value G. B The model sample was then left to stand for one week in a low-temperature, low-humidity environment at 0°C and 40% relative humidity, and then left to stand for another week in a high-temperature, high-humidity environment at 40°C and 80% relative humidity. After returning to room temperature (25°C and 50% relative humidity), the average gloss value of the model sample was calculated using the same method as above, and the gloss value G was calculated. C That's what I decided. The gloss value G is calculated using the following formula (4). C and gloss value G B Based on the absolute value ΔG of the difference, gloss stability was evaluated according to the following evaluation criteria. A smaller ΔG indicates less change in gloss after storage in low-temperature, low-humidity and high-temperature, high-humidity environments, and is considered to have superior gloss stability against environmental changes. ΔG = |G C -G B (4) <Evaluation Criteria> ◎ (Excellent gloss stability): 1.0≧ΔG ○ (Excellent gloss stability): 1.0 < ΔG ≤ 2.0 × (Poor gloss stability): 2.0 < ΔG

[0071] [Evaluation of application feel] A panel of 20 experts evaluated the application feel of model samples after they had been left standing for one week in a low-temperature, low-humidity environment (0°C, 40% relative humidity) and a high-temperature, high-humidity environment (40°C, 80% relative humidity) for the same period. Additionally, the application feel of a model sample left standing for one week in a normal temperature, normal-humidity environment (25°C, 50% relative humidity) was also evaluated and used as the baseline application feel. For both the low-temperature, low-humidity and high-temperature, high-humidity environments, a score of 0 to 3 was assigned based on whether there was a difference compared to the baseline application feel, according to the evaluation criteria below. Furthermore, for "application feel," we evaluated the softness of the model sample when applied to the skin, how easily it blended into the skin, and the degree of stickiness after it had been absorbed. <Evaluation Criteria> (Rating): (Evaluation result) 3 points: The application feel under both environmental conditions (low temperature, low humidity and high temperature, high humidity) is completely identical to the standard application feel. Two points: In one of two environments—low temperature and low humidity—the application feel is no different from the standard application feel. However, in the other environment, there is a slight difference in the application feel compared to the standard application feel. 1. There is a slight difference in the application feel under both environmental conditions (low temperature, low humidity and high temperature, high humidity) compared to the standard application feel. 0 points: The application feel in either a low-temperature, low-humidity environment or a high-temperature, high-humidity environment, or both, is clearly different from the standard application feel.

[0072] Furthermore, using the average score of all panelists' ratings, we determined the differences in application feel due to differences in the environment in which the cosmetics were used, according to the following criteria. <Judgment criteria> (Judgment): (Average score) ◎: 2.6 or higher ○: 2.0 or higher and less than 2.6 ×: Less than 2.0

[0073] [Table 5]

[0074] Model samples O-1 to O-16 containing the wax compositions W-1 to W-12 of the present invention showed little change in gloss after storage in low-temperature, low-humidity and high-temperature, high-humidity environments, demonstrating excellent gloss stability against environmental changes. Furthermore, the difference in application feel between normal temperature and humidity environments and low-temperature, low-humidity environments, as well as the difference in application feel between normal temperature and humidity environments and high-temperature, high-humidity environments, was small, indicating that differences in application feel due to differences in usage environments were reduced. On the other hand, model samples O-17 to O-23 containing wax compositions W-13 to W-19, which are not the wax compositions of the present invention, showed significant differences in application feel between normal temperature and humidity environments and low temperature and low humidity environments, and also significant differences in application feel between normal temperature and humidity environments and high temperature and high humidity environments, or both. Furthermore, model samples O-17, O-19, and O-21 to O-23 showed significant changes in gloss after storage in low temperature and low humidity environments and high temperature and high humidity environments, and exhibited poor gloss stability against environmental changes.

Claims

1. A wax composition containing two or more monoester Ms represented by the following structural formula (1), Of the two or more types of monoester M, the monoester M with the highest content is... Ａ , and the number of carbon atoms in the molecule is the same as the monoester M Ａ Monoester M, which is 4 or more more than that. Ｂ Includes one or more types, The total content of the monoester M is 90 to 99 parts by mass per 100 parts by mass of the wax composition, and the monoester M Ａ The content of is 50 to 98 parts by mass, and the monoester M Ｂ The total content is 1 to 15 parts by mass, A wax composition for cosmetic use, wherein the melting point of the wax composition is 60°C to 80°C. R １ C--R ２ (1) [In formula (1), R １ CO represents a linear saturated acyl group having 16 to 34 carbon atoms, and R ２ represents a linear alkyl group having 16 to 34 carbon atoms.]

2. The aforementioned monoester M Ａ However, the aforementioned R １ The number of carbon atoms in CO is C １ , the R ２ The number of carbon atoms C ２ The cosmetic wax composition according to claim 1, wherein the following formula (2) is satisfied. C １ ≠C ２ (2)

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