COSMETIC COMPOSITIONS CONTAINING LOW MOLECULAR WEIGHT AMORPHOUS GRADE POLYLACTIC ACID RESIN

Abstract

Cosmetic compositions contain certain polylactic acid resins as film-formers. The polylactic acid resin is effective at low levels in the composition and is compatible with many organic ingredients commonly used in cosmetic compositions. The cosmetic composition can be formulated as a spray, a lotion, a cream or a paste.

Claims

1. A cosmetic composition for applying a film on lips, skin, or eyelashes, the cosmetic composition comprising (component 1) at least one of (i) a water-immiscible organic compound having a molecular weight of up to 1000 g/mol, a melting temperature no greater than 60° C., and a boiling temperature at 101 kPa pressure of at least 100° C., and (ii) a water-immiscible silicone compound; and (2) an amorphous grade polylactic acid resin containing at least 70% by weight of lactic repeating units and having a glass transition temperature of no greater than 65° C., wherein the polylactic acid resin has a number-average molecular weight of 1000 to 12,000 g/mol and contains a residue after removal of hydroxyl groups of a hydroxyl-containing initiator compound having 2 to 24 carbon atoms and 1 to 8 hydroxyl groups, the polylactic acid resin constituting 0.1 to 10% of the total weight of the cosmetic composition and being dissolved in component 1 or an oil phase in which component 1 also is dissolved.

2. (canceled)

2. The cosmetic composition of claim 1 wherein the polylactic acid resin is a polymer of meso-lactide or a copolymer of a lactide mixture containing at least 75% meso-lactide and at most 25% of another lactide.

3. The cosmetic composition of claim 2 wherein the polylactic acid resin furthers contain repeating units of at least one other monomer that is copolymerizable with lactide or lactic acid.

4. The cosmetic composition of claim 1 wherein the polylactic acid resin is represented by the structure: ##STR00002## wherein y is 1 to 8, x is a positive number such that the polylactic acid resin has a number-average molecular weight of 1000 to 12,000 g/mol and R is the residue after removal of hydroxyl groups of a hydroxyl-containing initiator compound having y hydroxyl groups.

5. The cosmetic composition of claim 1 wherein the polylactic acid resin has a number average molecular weight of 2000 to 8000 g/mol.

6. The cosmetic composition of claim 1 wherein the hydroxyl-containing initiator compound is a linear or branched aliphatic monoalcohol having 6 to 20 carbon atoms.

7. The cosmetic composition of claim 1 wherein the hydroxyl-containing initiator compound is a linear or branched aliphatic alcohol having 3 to 9 carbon atoms and 2 to 4 hydroxyl groups.

8. The cosmetic composition of claim 1 wherein component 1 includes one or more of a fatty acid ester, a fatty alcohol, or an organic sunscreen.

9. The cosmetic composition of claim 1 which is an oil-in-water or water-in-oil emulsion.

10. The cosmetic composition of claim 9 that contains 5% to 90% by weight water.

11. The cosmetic composition of claim 10 which further comprises at least one water-soluble polymer.

12. The cosmetic composition of claim 1 which further comprises at least one emulsifier.

13. The cosmetic composition of claim 1 which further contains at least one particulate pigment.

14. The cosmetic composition of claim 1 which further comprises at least one of zinc oxide and titanium dioxide.

15. The cosmetic composition of claim 1 which further comprises at least one polyalcohol having 3 to 6 carbon atoms and a molecular weight of up to 125 g/mol.

16. The cosmetic composition of claim 1 which contains at least one organic UV absorber.

17. The cosmetic composition of claim 1 which is a sunscreen having a sun protection factor of at least 5 as measured according to the method described in 21 CFR § 201.357(i) (2011).

18. The cosmetic composition of claim 1 which is a sunscreen having a sun protection factor of at least 20 as measured according to the method described in 21 CFR § 201.357(i) (2011).

19. The cosmetic composition of claim 1 wherein the polylactic acid resin contains 20% to 80% of one lactic acid enantiomer and correspondingly 80% to 20% of the other lactic acid enantiomer, based on the total weight of lactic units in the polylactic acid resin.

Description

Examples 1 and 2 and Comparative Sample A

[0061] Oil-in-water sunscreens containing organic and inorganic UV absorbers (Comparative Sample A and Examples 1 and 2) are prepared as follows:

[0062] A water-dispersible premix is prepared by combining 10 parts by weight of 1,3-propanediol, 0.2 parts of xanthan gum, 0.2 parts of guar gum, 2 parts of ensulizole, 0.5 part of L-arginine, 1 part of a phenylpropanol/caprylyl glycol/1,3-propanediol mixture (Sensiva PA 40 from Schulke, Inc., Fairfield, N.J. USA), and (for Comparative Sample A only) 2 parts of maltodextrin (a water-soluble film-former) to form a viscous, homogeneous mixture. The premix then is heated to 70° C. and added to 49.1 parts of water and homogenized to produce an aqueous phase.

[0063] An oil/surfactant premix is prepared separately by combining 7.5 parts of homosalate, 2.5 parts of octisalate, 5 parts of octocrylene, 5 parts of di(ethylhexyl)naphthanate, 2 parts of an anionic surfactant (Dracorin GOC, from Symrise AG), 3 parts of a polyoxyethylene (20) sorbitan monolaurate, and (for Examples 1 and 2 only) 2 parts of a test film former at 70° C. 20 parts of zinc oxide are combined with the oil/surfactant premix, and the resulting dispersion is combined with the aqueous phase described above and homogenized to produce a white, sunscreen formulation.

[0064] The film-former in Example 1 is a 2296 g/mol M.sub.n polymer made by polymerizing a mixture of about 90% meso-lactide and 10% L-lactide onto pentaerythritol (“PLA-1”). PLA-1 has a glass transition temperature of 26° C. and contains about 94% lactic units. About 55% of the lactic units are L-lactic units.

[0065] The film-former in Example 2 is a 3614 g/mol M.sub.n polymer made by polymerizing a mixture of about 90% meso-lactide and 10% L-lactide onto 1-octadecanol (“PLA-2”). PLA-2 has a glass transition temperature of 14° C. and contains about 93% lactic units. About 55% of the lactic units are L-lactic units. (See Table 2 for additional physical property data on PLA 1 and PLA 2.)

[0066] Each of the sunscreens is subjected to SPF (sun protection factor) testing according to the method set forth in 21 CFR § 201.357(i) (2011). 0.05 gram of the test sunscreen is applied to a polymethyl methacrylate plate. It is spread using a circular motion for 30 seconds, using a vertical motion for 15 seconds, and then using a horizontal motion for 15 seconds. The coated plate is placed in a dark drawer for 15 minutes prior to SPF testing.

[0067] After the initial SPF testing, the coated plates are placed in an agitated 30° C. water bath for 20 minutes. The plates are then removed and allowed to dry in air. The dry plate are then again subjected to SPF testing. Results of the SPF testing are as indicated in Table 1.

TABLE-US-00004 TABLE 1 SPF Test Results Sample Film Former Before Washing After Washing A* Maltodextrin 97.8 48.7 1 PLA-1 90.0 66.2 2 PLA-2 138.2 68.4 *Comparative

[0068] Examples 1 and 2 perform comparably or better than the comparative sample before washing. Good performance on SPF testing is indicative of film formation when the sunscreen is applied; much poorer results are obtained when good film formation does not take place. Examples 1 and 2 perform much better than the comparative sample after the plates have been washed. The better wash-off resistance again is indicative of good film formation.

Examples 3-9

[0069] Oil-in-water sunscreen Examples 3-9 are made in the following general manner. A water-dispersible premix is made by combining 20 parts of 1,3-propane diol, 0.5 parts of a xanthan gum/guar gum mixture, 2 parts of ensulizole, 0.5 parts of L-arginine, 1.0 part of Sensive PA 40, and 2 parts of maltodextrin. The resulting mixture is combined with 47 parts of 80° C. water and maintained at 80° C. This produces an aqueous phase.

[0070] An oil/surfactant/zinc oxide phase is made by mixing at 75° C. 10 parts of a 50% dispersion of zinc oxide in a caprylic/capric triglyceride carrier, 7.5 parts of homosalate, 2.5 parts of octisalate, 5 parts of octocrylene, 5 parts of ethylhexyl palmitate, 2 parts of sorbitan oleate, 3 parts of poly(propylene glycol)60 sorbitan monolaurate, and 2 parts of a film former. The film former in each case is a polylactic acid resin made by polymerizing a mixture of about 90% meso-lactide and 10% L-lactide onto an initiator, as described in Table 2. The sunscreen is then made by adding the 75° C. oil/surfactant/zinc oxide phase into the 80° C. aqueous phase and homogenizing.

TABLE-US-00005 TABLE 2 PLA % Lactide Example sample Initiator M.sub.n, g/mol T.sub.g, ° C. Units 3 PLA-3 Lauryl alcohol 2907 16.4 93.6 4 PLA-4 1-Octadecanol 5256 25 94.9 5 PLA-5 Capryl alcohol 5261 33 97.5 6 PLA-6 Capryl alcohol 2588 17 95.0 7 PLA-7 Capryl alcohol 1134 −6.5 88.5 8 PLA-8 1-Octadecanol 1165 11 76.9 9 PLA-2 1-Octadecanol 3615 14.1 92.6

[0071] The Brookfield viscosities of each of sunscreen Examples 3-9 are determined at 23° C. using a Varispeed method with a #27 spindle. SPF is measured in each case as described before. Results are as indicated in Table 3.

TABLE-US-00006 TABLE 3 Example PLA sample Viscosity, cP SPF 3 PLA-3 271 22.3 4 PLA-4 2550 30.9 5 PLA-5 1965 14.4 6 PLA-6 2350 7.9 7 PLA-7 515 9.8 8 PLA-8 2940 18.9 9 PLA-2 9780 22.7

[0072] The SPF data in Table 3 reveals a correlation between the length of the initiator of the polylactic acid resin and SPF values. In general, longer initiator chain length corresponds to better SPF values. PLA molecular weight affects viscosity but has little effect on SPF values.

Examples 10 and 11

[0073] Foundation Examples 10 and 11 are made in the following general manner. 40 parts 1,3-propanediol, 2 parts of a styrene maleic anhydride copolymer (MSA 1800 from Cray Valley), 6 parts of ensulizole, 16 parts titanium dioxide particles, and 2 parts of Sensive PA 40 are combined. Separately, 0.4 parts of xanthan gum, 6 parts of modified cornstarch (ICB 3000 from Tate and Lyle), and 3 parts of a sodium starch octenylsuccinate/cucurbturils mixture (Aqstar M1, Aqdot Company, Cambridge, UK) are combined. The two mixtures are then homogenized together. To the homogenized materials is added a mixture of 1.4 parts iron oxide red, 4.2 parts of iron oxide yellow, and 0.4 parts iron oxide black (available from Making Cosmetic Color) followed by further homogenization. The resulting mixture is then blended with 71.6 parts of 80° C. water. The result is a dispersion of the pigments in an aqueous phase.

[0074] Separately, 30 parts of a diacetylated monoglyceride prepared from soy feedstocks, 2.5 parts of cetyl alcohol, 1.5 part of the sodium starch octenylsuccinate/cucurbturils mixture, 4 parts of a mixture of glyceryl oleate citrate and caprylic/capric triglyceride, 1 part of fumed silica, and 4 parts of a polylactic acid resin are combined at 75° C. to produce an oil/surfactant phase. The 75° C. oil/surfactant phase is then blended into the 80° C. aqueous pigment dispersion and homogenized to produce the foundation.

[0075] The polylactic acid resins in Examples 10 and 11 are PLA-1 and PLA-2, respectively.

[0076] Examples 10 and 11 are evaluated SPF rating as before, both before and after washing. Results are as indicated in Table 4.

TABLE-US-00007 TABLE 4 SPF Test Results Sample Film Former Before Washing After Washing 10 PLA-1 12.7 9.3 11 PLA-2 10.6 7.4

[0077] Both PLA film-formers impart good wash-off resistance to the foundation formulations.

Examples 12-18 and Comparative Sample B

[0078] Foundation compositions (Examples 12-18) are made in the following general manner. A premix is made by combining 20 parts of 1,3-propanediol, 1 part of an SMA/MA copolymer, 0.7 parts of a hydroxypropyl starch phosphate, 0.3 parts of guar gum, and 2 parts of maltodextrin. Separately, a pigment mixture containing 0.3 parts of iron oxide red, 1 part of iron oxide yellow, 0.1 part of iron oxide black, and 8 parts of titanium dioxide is formed. The pigment mixture and premix are combined until uniform, and then combined with 42.5 parts of 85° C. water. This produces an aqueous phase in which the pigments are dispersed.

[0079] An oil/surfactant phase is made by mixing 5 parts of a diheptyl succinate/capryloyl glycerin sebacic acid copolymer mixture (LexfeelN50, Inolex, Inc.), 2 parts of cetyl alcohol, 1 part of a sodium starch octenylsuccinate/cucurbturils mixture (Aqstar M1, Aqdot Company, Cambridge, UK), 10 parts of a triheptanoin/C13-16 paraffin mixture (Lexfeel from Inolex), 2.0 parts of sorbitan oleate, 2.0 parts of a polyethyleneglycol 60 sorbitan monolaurate, 0.1 part of fumed silica, and 2 parts of a film former (except in Comparative Sample B, in which the film former is omitted). The film former in each case is a polylactic acid resin as indicated in Table 5. The sunscreen is then made by combining the 85° C. aqueous phase with the 75° C. oil/surfactant phase and homogenizing.

[0080] Viscosity and SPF rating are determined on each sample in the manner described before. Transfer resistance is determined by applying a preweighed sample of the foundation onto a 2 cm×2 cm square section of a human subject's forearm using a doe foot applicator and allowed to dry for one minute. The applicator is reweighed to calculate the amount of foundation applied to the skin. A weighed 3 cm×3 cm tissue is then applied to the applied foundation and dragged 3 cm. The tissue is then re-weighed to measure the amount of foundation removed. The amount transferred is then calculated as 100%×(wt. removed÷wt. applied).

[0081] Results of the testing are as indicated in Table 5.

TABLE-US-00008 TABLE 5 Example PLA resin Viscosity, cP SPF rating Transfer, % 12 PLA-3 514 4.3 14.9 13 PLA-4 2355 5.8 17.6 14 PLA-5 1058 4.6 15.7 15 PLA-6 290 2.9 17.0 16 PLA-7 526 3.0 21.4 17 PLA-8 2655 3.8 26.3 18 PLA-2 1465 3.9 21.8 B* none 2155 3.4 43% *Comparative.

[0082] All of the polylactic acid resins are shown to be effective film-formers, as indicated especially by the excellent transfer resistance compared with the control (Comparative Sample B). For comparison, 43.1% of the mass transfers when an otherwise identical foundation formulation, but lacking film-former, is tested.

Examples 19-20 and Comparative Sample C

[0083] Water-in-oil sunscreen formulations are prepared as follows: 10 parts propane diol, 1 part of caprylhydroxamic acid, 0.5 parts zinc lactate, and 0.2 parts of L-arginine are mixed at room temperature with 49.3 parts of water to form an aqueous phase. Separately, an oil/surfactant/zinc oxide phase is prepared by mixing 19 parts of a C15-C19 alkane mixture (Emogreen L15, Seppic S.A.), 1 part of Dracorin GOC, and 1 part of tri(Polyglyceryl-3/Lauryl) Hydrogenated Trilinoleate. 15 parts of zinc oxide are added to the mixture and dispersed until homogenous. The oil/surfactant/zinc oxide phase is warmed to 75° C., 3 parts of a film former (as indicated in Table 6) are added, and mixed until uniform. The aqueous phase is combined with the oil phase at 75° C. and is mixed until homogenized to produce a white lotion. Viscosity and SPF both before and after washing are measured as before. Results are as in Table 6.

TABLE-US-00009 TABLE 6 SPF rating Example PLA resin Viscosity, cP Before Washing After Washing 19 PLA-1 1350 9.6 10.5 20 PLA-2 1830 13.3 12.0 C* none 2920 7.7 8.0 *Comparative.

[0084] The increase in SPF rating seen with Examples 19 and 20 relative to Comparative Sample C indicates the PLA resins are effective film-formers in this formulation.

Examples 21-22

[0085] Oil-in-water sunscreen formulations containing only an inorganic sunscreen are prepared as follows: 0.3 parts of xanthan gum, 10 parts propanediol, 1 part of a caprylhydroxamic acid/glyceryl caprylate mixture, 0.5 parts of L-arginine, and 1 part of hydrolyzed corn starch hydroxy ethyl ether are mixed with 43.2 parts of water until homogenized to form an aqueous phase. The aqueous phase is heated to 75° C. An oil/surfactant/zinc oxide phase is prepared by combining 20 parts of an isoparaffin mixture (Lexfeel WOW), 15 parts of zinc oxide, 3 parts of a film-former as indicated in Table 7, 1 part of Dracorin GOC), 3 parts of sodium behenoyl lactylate are combined at 75° C. and mixed until homogenous. The phases are mixed and homogenized. Viscosity and SPF (before and after washing) are measured as before, with results as reported in Table 7.

TABLE-US-00010 TABLE 7 SPF rating Example PLA resin Viscosity, cP Before Washing After Washing 19 PLA-1 21500 9.0 10.6 20 PLA-2 5900 9.7 6.7

Examples 23 and 24

[0086] Lipstick formulations are produced as follows: 30.8 parts of castor oil, 16 parts of caprylic/capric triglyceride, 17 parts of isoeicosane, 5 parts of meadowfoam seed oil, 3.5 part of microcrystalline wax, 3.5 part of ozokerite wax, 7 parts of candelilla wax, 3 parts of carnauba wax, and 1 part of a film-former as indicated in Table 8 are combined at 80-95° C. to form a molten wax phase. Separately, 1 part of Red No. 7 D&C Lake and 11 parts of mica are combined, and then mixed into the molten wax phase. 0.2 parts of tocopherol and 1 part of paraben-DU (mixture of 56% propylene glycol, 3% propylparaben, 11% methylparaben and 30% diazolidinyl urea) are mixed and then combined with the molten wax phase. The resulting lipstick formulations are poured into a lipstick mold and solidified in a freezer.

[0087] The lipsticks are tested for transfer resistance in the manner described before. Hardness and penetration force are measured according to ASTM D1321-10. Results are as indicated in Table 8.

TABLE-US-00011 TABLE 8 Hardness (g- Penetration Force Sample % Transfer force) for 7 mm PLA-1 12 442 131 PLA-2 13 380 126

Examples 24-33 and Comparative Sample A

[0088] Comparative Sample A: 20 parts of coconut oil and 3 parts of PLA-1 are heated separately to 90° C. and mixed by hand. The resulting mixture is homogeneous upon visual inspection at that temperature. When this experiment is repeated at 80° C. the mixture is only partially homogeneous and is entirely heterogeneous when the mixture is made at 70° C. When the coconut oil and PLA-1 are mixed at a 3:1 ratio at 80° C., the resulting mixture is completely heterogenous.

[0089] Example 24: Glycerol monostearate and coconut oil are combined at a 68/32 weight ratio. Entirely homogeneous mixtures are obtained when 20 grams of that mixture and 3 parts of PLA-1 are separately heated to 70° C. and combined. Similar results are obtained when the mix ratio is 3:1. Upon cooling, these mixtures partially phase separate but are easily combined with an aqueous phase at 70° C. to produce a cosmetic formulation.

[0090] Example 25: Glycerol monooleate and coconut oil are combined at a 84/16 ratio. Partially heterogeneous mixtures are obtained when 20 grams of that mixture and 3 parts of PLA-1 are separately heated to 70° C. and combined; at 80° C. the mixtures are entirely homogeneous. When the mix ratio is 3:1, partially heterogeneous mixtures are obtained at both the 70° C. and 80° C. mixing temperatures. Upon cooling, these mixtures partially phase separate but are easily combined with an aqueous phase at 70° C. to 80° C. to produce a cosmetic formulation.

[0091] Example 26: Glycerol monooleate and glycerol monolaurate are combined at a 63/37 ratio. Partially heterogeneous mixtures are obtained when 20 grams of that mixture and 3 parts of PLA-1 are separately heated to 70° C. and combined; at 80° C. the mixtures are entirely homogeneous. When the mix ratio is 3:1, completely homogeneous mixtures are obtained at both the 70° C. and 80° C. mixing temperatures. Upon cooling, these mixtures partially phase separate but are easily combined with an aqueous phase at 70° C. to 80° C. to produce a cosmetic formulation.

[0092] Example 27: Propylene glycol monooleate and coconut oil are combined at a 99/1 ratio. Fully homogeneous mixtures are obtained when 20 grams of that mixture and 3 parts of PLA-1 are separately heated to 80° C. and combined. Upon cooling, these mixtures partially phase separate but are easily combined with an aqueous phase at 80° C. to produce a cosmetic formulation.

[0093] Example 28: Glycerol monostearate and coconut oil are combined at a 63/37 ratio. Partially heterogeneous mixtures are obtained when 20 grams of that mixture and 3 parts of PLA-1 are separately heated to 80° C. and combined. Upon cooling, these mixtures partially phase separate but are easily combined with an aqueous phase at 70° C. to 80° C. to produce a cosmetic formulation.

[0094] Example 29: Propylene glycol monooleate and coconut oil are combined at a 55/45 ratio. Partially heterogeneous mixtures are obtained when 20 grams of that mixture and 3 parts of PLA-1 are separately heated to 80° C. and combined. Upon cooling, these mixtures partially phase separate but are easily combined with an aqueous phase at 80° C. to produce a cosmetic formulation.

[0095] Example 30: Glycerol monostearate and coconut oil are combined at a 68/32 ratio. Partially heterogeneous mixtures are obtained when 20 grams of that mixture and 3 parts of PLA-4 are separately heated to 80° C. and combined. When the mix ratio is 3:1, partially heterogenous mixtures are obtain at both 70° C. and 80° C. Upon cooling, these mixtures partially phase separate but are easily combined with an aqueous phase at 70° C.-80° C. to produce a cosmetic formulation.

[0096] Example 31: Glycerol monooleate and coconut oil are combined at a 84/16 ratio. Partially heterogeneous mixtures are obtained when 20 grams of that mixture and 3 parts of PLA-4 are separately heated to 70° C. and combined; at 80° C. the mixtures are entirely homogeneous. Upon cooling, these mixtures partially phase separate but are easily combined with an aqueous phase at 70° C. to 80° C. to produce a cosmetic formulation.

[0097] Example 32: Glycerol monooleate and glycerol monolaurate are combined at a 63/37 ratio. Partially heterogeneous mixtures are obtained when 20 grams of that mixture and 3 parts of PLA-4 are separately heated to 80° C. Similar results are obtained when the mix ratio is 3:1. Upon cooling, these mixtures partially phase separate but are easily combined with an aqueous phase at 80° C. to produce a cosmetic formulation.

[0098] Example 33: Propylene glycol monooleate and coconut oil are combined at a 99/1 ratio. Fully homogeneous mixtures are obtained when 20 grams of that mixture and 3 parts of PLA-4 are separately heated to 80° C. and combined. Upon cooling, these mixtures partially phase separate but are easily combined with an aqueous phase at 80° C. to produce a cosmetic formulation.

Examples 34 and 35

[0099] Example 34: 6.0 parts of coconut oil, 10.2 parts of glycerol monostearate and 5.4 parts of PLA-4 are combined, heated to 80° C. for one hour, and cooled to room temperature to form a premix.

[0100] Separately, a water phase is prepared by mixing 44.55 parts water, 0.55 parts xanthan gum and 9.9 parts of 1,3-propanediol.

[0101] A lotion is prepared by heating the premix to 80° C. and combining it with 18 parts of coconut oil, 1.8 parts of glyceryl oleate citrate and 3.6 parts of steareth-21 surfactant to produce an oil phase. The water phase is heated separately to the same temperature. The oil phase is poured slowly into the water phase under mild agitation conditions of about 400 rpm. The agitation rate is increased to 1000 rpm and is continued for 5 minutes after the phases are combined. The resulting product is a homogeneous lotion that is resistant to phase separation.

[0102] Example 35 is made in the same manner, except PLA-4 is replaced with PLA-1. Similar results are obtained.