CA2013669C - Stable emulsions of perfluoropolyethers - Google Patents

Abstract

Stable diphase emulsions consisting of :
a) perfluoropolyethers having perfluoroalkyl end groups;
b) a conventional surfactant, dispersed in c) a continuous dispersing phase consisting of glycerol or of a polyhydroxylated compound containing at least three hydroxyl groups, selected from polyalcohols and saccharides, dissolved in a hydrophile solvent and/or water.

Description

"STABLE E;dULS:O~~S OF PERFLUOROPOLYETHERS"
The present invention relates to stable emulsions of perfluoropolyethers.
In particular, the present invention relates to stable diphase emulsions comprising a liquid perfluoroether component and an organic hydroxylated hydrating and/or wet-ting agent.
The emulsions of the present invention may be utilized in several known industrial applicative fields for perfluoropolyethers, and in particular in the field of the cosmetic and dermatological specialities and fur-thermore as so-called premixes in the preparation of the above-said specialities.
The use of perfluoropolyethers as ingredients of various cosmetic and dermatological preparations is Kno:~;n in itself, owing to the possibility of obtaining a protective film on the skin, which film does not represent a hindrance to the physiological functions tsuch as transpiration, etc.).
~~evertheless, difficulties are encountered in the production of cosmetics, which are due to the fact that perfluoropoly-ethers are in general insoluble in the raw materials utiliz-ed in the cosmetic industry, or, at least, it can happen that the performances of the product are jeopardized by a non-homo-geneous distribution of the perfluoropolyethers in the cosme-tic preparation. In fact, the perfluoropolyethers are fully insoluble in all the organic matters, except in those having a high fluorine content, wherefore the technology has to face the general problem of obtaining dispersions of perfluoropoly-ethers in organic or aqueous-organic liquids, as the perfluoro-polyethers are liquids.
In literature is known the preparation of oil/water emul si ons i n whi ch the of 1 consi sts of a perfluorinated compound.
These emulsions have been prepared essentially to the pur-pose of having available synthetic plasma, utilizing the high - 3 - ~~~.~~ ~~"
solubility of oxygen and carbon dioxide in the perfluorinat-ed cor~pounds which, in such manner, acted as oxygen trans-ferors. The utilized perfluorinated compounds belong to the class of the perfluororinated cycloal~<anes (preferably having two or r~ore con-densed cycles), of the perfluorinated heterocyclic compounds and of the perfluorinated amines. As emulsifiers, the best ones have proven to be the non-ionic emulsifiers and part-icularly the so-called pluronic emulsifiers (non-ionic emsul-sifiers having a chemical structure of polyalkyloxanes and prepared starting from mixtures of ethylene oxide and pro-pylene oxide in a proper ratio). As an alternative, pex-fluorinated er;~ulsifiers have been used with the possibility of obtaining e~-nulsions and microemulsions; the uses thereof, however, are limited just by the presence of said surfactants.
This technology has not been particularly suitable for the compounds having the structure of perfluoropoly-ethers, especially if their molecular weight is higher than 1000. In the preparation of emulsions of the latter, two main difficulties were encountered, which were represented by the choi ce of an eff ective emul si f i er and by the ob-tainment of sufficiently stable products.
On the other hand it is known to prepare cos-metic three-phase emulsions in which the perfluoropoly-ether is dispersed in an oil/water or water-oil emulsion or in a cross-linking solid phase suspended in an organic liquid ~~~.~

phase.
To the Applicant's knowledge, no di phase systeir~s have Seen described heretofore, which consist of two liquids, one of which consisLS of a peofluoropolyether and the other of an organic optionally aqueous substance, in the form of a dispersion of one in the other in order to form a stable emulsion, with the addition of cor~~mon surfactants, and in particular of non-fluorinated surfactants.
Thus, i~ is an object of the present invention to prov i de a diphase e~aul si on i n the forr;~ of a fi ne and homo-geneous dispersion of perfluoropolyethers in an organic subs-Lance, nationally in the presence of vrater, which acts as a continuous phase, in the presence of conventional surfactants or e;~,ulsifiers.
~noth,er object is that of providing the correspond-ing ~,~ethod of preparation, while further objects are the con-positions containing the abovesaid stable emulsions and the use thereof in the cosmetic and dermatological field.
Accordingly, the present invention provides stable emulsions of perfluoropolyether liquids having perfluoroalkyl end groups in a continuous phase of a polyhydroxylated compound selected from glycerol and solutions in hydrophile solvents of polyalcohols,other than glycerol, or saccharides, as described hereinafter, (, J!

in the presence of conventional surfactants. In this way s~a5le, also anhydrous, emulsions are obtained, which are utiliza5le in she industrial applicative fields which are known for the perfluoropolyethers. In particular, due to ~he filr~-forming characteristics of the perfluoropolyether component, the emulsions of the present invention,~y ~ ~~ uycompositions, creams, pastes, pseudo--solid e~;,ulsions, and the like, to which they impart the pro-perty of forming a transparent, water-repellent and lipo-re-pellent liquid fil,o, also endowed with permeability .to oxygen and other gases, which remains on the surface, on which it is aaplicai:ed, for rela~ively long periods of time.
The characteristic water-and lipo-repellentproperties of the liquid film, make the compositions particularly suitable for appliances in the protective prepa-rations field and for highly effective appliances in the cosmetics and/or dermatological treatments range. In comparison with conventional preparations, those having a water- and lipo-repellent action afford the weighty advantage of keeping a last during effectiveness. In the skin re-hydration treatments it is highly desiderable to have available stable, cosmetically acceptable (non-greasy, non-tacky, etc.! compositions, which, besides exhibiting the property of maintaining in the subcutaneous layers such water amounts as are sufficient to retain the elasticity, are also capable of exerting a "barrier" effect towards the outside without, however, adversely affect the skin transpiration.
The compositions of the invention, due to the perfluoropolyether component contained therein as a stable emulsion, according to the object of the present invention, allow to achieve these objects.

a.~ - 6 _ As mentioned hereinbefore, the stable diphase emul-sions of the present invention, consist of a fine and homogeneous stable dispersion of at least a per-fluoropolyether,having perfluoroalkyl end groups, inside a con-tinuous phase of a polyhydroxylated compound selected from glycerol and solutions of polyalcohols or saccharides in hydro-phile solvents or water, in the presence of usual surfactants or emulsifiers. The perfluoropolyethers having perfluoroalkyl end groups, i.e. free from functional groups, are well-known cor~~;~ounds, which are described, along with the method for pre-paring them, in several documents, among which British patent 1,104,482, U.S. patents 3,242,218, 3,665,041, 3,715,378, 4,523,039, European patent applications 148,482, 151,877 and 191,490 and international patent applications ~JO 87/00533 and :JO 37/02992.
Suitable perfluoropolyethers are, for example, the ones characterized by the presence of one or more repeating perfluoro-oxyalkylene units a) (CF2-CF20) b) (CF20) c) (C3F60), simplified formula for (CF2-CF-0) CF

d) (CF20-CFZ-CF20) e) (CF2-CF2-CF20) f ) ( CFO ) CFA
J
IF3 Rf~ ~ ~ Rf g ) C-0 C C 0 F
f f wherein groups P f"' , 1 i ke or di fferent fror~ one another, are a fluorine atop or a perfluoroalkyl group.
Preferably the perfluoropolyethers suitable for the present invention exhibit the following individual per-fluoro-oxyalkylene units or the following conbinat~ions of perfluoro-oxyalkylene units:
I) (CF2-CF20) and (CF20), said units being statistical-ly distributed along the perfluoropolyether chain; or I I ) ( CF2-CFC ) and ( CFXG ) , wherein X i s F or CF3 , said units being statistically distributed along the chain; or III) (CF2-CF20), (CF2-CFO) and (CFXO) in which X is F or CF3, said units being statistically distributed along the chain; or IVi (CF-CF20) .
or V) (CFZ-CF2-CF20); or VI) (CF2-CF20); or _8_ vI I ) ", R ", I F3 Rf .f C - 0 -.--1C .~-~.- C T--0 CF R rn ~ ", 3 f f w~~erein groups R f' ' ' , 1 i ke or di fferent from one another, are a fluorine ato~~ or a perfluoroalkyl group; or 'J I i I ) ( C. z0-CF2-CFZO ) .
Suitable perfluoropolyethers are also the ones which contain perfluorooxetane rings -C -C- or -C C-R
in which i, B and R, like or different from one another, are perfluoro-cxyalkyl, perfluoropolyoxyalkyl or perfluoroalkyl radicals and ;; is a perfluorooxyalkyl, perfluoropolyoxyalkyl or perfluoroalkyl radical.
Exa~ples of suitable perfluoropolyethers having re-peating aerfluorooxyalkylene units are the ones belonging to the following classes:
Rf-0-(C3F60)a(IF-0)b(CF20)c-R'f wherein . Rf and R' f, like or different from each other, are selec'~ed fro~~ the group consisting of CF3, C2FS and C3F~;
units C3~'60 (oxytrifluoromethyltrifluoroethylene), CF-0 and ~~~3~~

C~2-0 are statistically distributed along the chain;
a .s an integer;
and C are i n;,e5er~s or zero;
d when tine sure ( a+c ) i s other than zero, the b+c ratio ranges fror~ 5 to ~0;
B) CF30-(C2F40)d(CF20)e-CFJ
wherein units CZ; TO and CF20 are statistically distributed along the chain; d and a are integers; the d/e ratio rang-ir;g frog 0.3 tc ~;
C) CF~O-(CJFUJ)~tC,,r40) (CrXO)h-CFJ .

wherein un i :s ~.,; ~, C F ~ and CFXO are statist ical ly di s-~~~i~u~ec' along the chain;
i s F or f, g and h are integers;
;:«e g+r ratio varies from 1 to 50, and ;,he h ratio varies from 1 to 10;
C) f:3f0-(C~'2CF2CF20)jZ4f wherein ~' f and R~' f, 1 i ke or di fferent from each other, are -CF3 or -C2F5 and j is an integer.
The perfluoropolyethers suited to be used in the present i nven ti on typically have a number average mol ecul ar weight ranging from 500 to 20,000 and, more usually, from 1,000 to 10,000.
As r~entioned above, the perfluoropolyethers - to - 20~.~
according to ~I;e present invention are dispersed in emulsion i ns i de a c;;r;ti nuous abase of a polyhydroxyl a;.ed cor,~pound se-t ec ~ed facr:~ glycerol as such and polyal cohol s and sacchari des in concentrated solution in a hydrophile solvent or water, containing at least tree hydroxyl groups, preferably in the a5sence of i;ydrogenated carbon atoms.
hs regards glycerol, it is the preferred conpound and i~ can 5e used just as it is available i~ conmerce, ge-nerally containing up to 5a of water.
~;ny ;,olyalcohol can be utilized provided t~;a~ it shoula be liquid in ambient conditions or that it ;h~ouln ~e s;,lu;;le in the hydrophile solvent or in water ~~r~il o~:ain;;~ent ;:f concentrated solutions.
Sui~aSle a~lyalcohols are for example the ones '.:hic~ con:ain freu.; 3 to 12 carbon atoms with at least 3 hy-c~-ox~1 groups other than glycerol. In like manner, under the Sa~~ie condi~ions of solubility in the hydrophile solvent it is possi5le ~o use the saccharides (from mono- to tri-sacchar-ides) C~-Cla and/or nixtures thereof like the ones obtainable fro~;~ the hydrolytic demolition of polysaccharides such as cellulose and starch.
Suitable hydrophile solvents are, for example, glycols, glycerol itself, lower alcohols, ethereal solvents, diglymesetc., also if acqueous.
However, it is usually operated with water.

The hydrophile solvent is used in the lowest amount sufficient to obtain a concentrated solution (syrup) of the polyalcohol or saccharide compound.
However, the concentrated aqueous solutions (syrups) of polyalcohols and saccharides (sugars) available on the market are utilizable.
The concentration of the solutions usually amounts to a value ranging from 50 % to 80 % by weight. Glycerol is used as such because it is already in the liquid state.
The following polyalcohols and saccharides have proved to be particularly effective: glycerol, xylitol, mannitol, sorbitol, glucose, fructose, saccharose, maltitol, dimer compounds of glycerol (di-glycerol or bis(2,3-di-hydroxypropyl) ether, solid water soluble polyhydroxylated compounds as sugars and glycerol condensation products as tryglycerol and tetraglycerol.
These are known compounds which are in the form of crystalline powders soluble both in water and in hydroxylated solvents.
The dispersion in emulsion is carried out, last, in the presence of conventional surfactants, preferably of the cosmetic type. The surfactants of the cationic, anionic, amphoteric and non-ionic type have proved to be useful compounds, the preferred ones being those of the ionic type.
Among the others, the following ones have proved to be effective:
- sodium lauryl sulphate (solution at 28 % ) Texapon N40~ (Henkel), - sulphosuccinate (sulphosuccinic hemiester) (solution at 30 % ) Texapon SB 3~ (Henkel), - coco-amphocarboxyglycinate (solution at 40 % ) Dehyton D~ (Henkel), - potassium cetyl phosphate (solid product) Amphisol K~ (Givaudan), - sodium alkyl-polyoxyethylene-ether carboxylate Nikkol ECTD-3NEX~ (Nikko Chemicals), - potassium benzalconium chloride (solution at 50 % ) (purchased from trade company Res Pharma), - alkyl amidopropyl betaine (solution at 40 % ) Dehyton K~ (Henkel).
As already mentioned, sufficiently stable emulsions have been prepared also with non-ionic emulsifiers such as:
- cetyl-stearilic ethoxylated alcohol Emulgin Bl~ (Henkel), - sorbitan-ethoxylate(20)-mono-oleate Tween 20~ (ICI Speciality Chemicals).
The quantitative ratios of the components of the stable emulsion according to the present invention can be defined as follows:
1. In the case of using glycerol as the continuous phase:
a) perfluoropolyether: from 0.01 % to 99.9 % , preferably from 0.1 % to 75 % , by weight referred to the total weight of the emulsion;

..._... s~; ~-a. r~ ~, b) surfactant: fron 0.01% to 30%, preferably from 0.01%
to 5;0, by weight referred to the total weight of the emulsion and at any rate the lowest possible amount;
c) glycerol: the balance to 100% by weight.
2. In the case of using polyalcohols or saccharides (in the solid state) dissolved in the least hydrophile solvent a~TOUnt necessary to obtain a concentrated solution (sy-rup in N20):
a) perfluoropolyether: frorn 0.01% to 30%, preferably from 0.01 ',o to 50%, by weight referred to the total weight of the e;~ulsion;
b) surfactant: fro"~ 0.01% to 30%, preferably from 0.01%
to 5'0, by weight referred to the total weight of the emulsion;
c) polyhydroxylated compound (polyalcohol or saccharide) exNressed at 100ro in the form of concentrated solution in the hydrophile solvent: the balance to 100%.
In the limits of the preferred per cent composi-Lions it is possible to obtain emulsion of the Newtonian type with particles of the order of 0.5-0.8 microns.
The emulsions of the present invention are prepared by adding a perfluoropolyether to a solution of a preferably ionic surfactant or emulsifier, as defined hereinbefore, in glycerol or in the polyalcohol or saccharide in concentrated solution (syrup in H20) in the above-specified ratios, main-taining the system under stirring, for example by means of a turboemulsifier Silverson L/2R~ at room temperature.
As already mentioned, the emulsions of the invention exhibit remarkable film-forming effects: the obtained liquid film is transparent and permeable to gases. A
significant proof of the waterproof effect is provided by applicating a cream according to the invention on the hands and then by washing the hands. After washing, water glides away leaving the skin dry.
Thanks to the above-mentioned properties, the emulsions of the invention are particularly suitable for applications in the field of cosmetology and dermatology.
Examples of these applications are:
a) as barrier creams and other protecting preparations (hand creams, ointments or pastes to prevent contact irritations and dermatitis; creams against dermatitis caused by household or work surfactants);
b) in the paedo-cosmetology as protective creams or pastes for children;
c) in the sun products to prolong the action thereof;
d) as anti-wrinkle products and for the decorative cosmetology, for example in products such as make-up foundation products eyeshadows and the like. In this case, the presence of the fluorinated compound promotes the flowability and therefore facilitates the spreadability of the products, thereby preventing or minimizing antiaesthetic caking of the product on the skin; in lipsticks and lip-;eu ~gcst:aw°

-glosses, for example, an improvement of both flowabili-ty and gloss is obtained;
e) as creams for :passages; since the fluorinated compound is not absorbed by the skin, it permits also prolonged mas-sages, thereby allowing the penetration of "active mat-tern", if any;
f) in der;patological applications, as a vehicle for the medicarnents.
The per cent ar~ount of perfluoropolyether in the cosmetic emulsions varies as a function of the type of end use, of the number of daily applications and of the application t i me . This amo a n t general ly ranges from 0.2-0.5% for the anti-wrinkle creams to be utilized every day, up to 3-5% for high-ly protective creams. The persistence of the perfluoropoly-ether on the skin is rather long: the elimination occurs either by washing or by diffusion on the clothes of by natur-al desquamation of the skin.
The following examples are given for illustrative purposes and are not to be considered as a limitation of the invention. Unless otherwise specified, all the parts are parts by weight.
Furthermore, the parts of polyalcohols or of sac-charides and of surfactant are indicated as such according to the indicated concentration.
The following perfluoropolyethers have been used:

- Fomblin HC/25~ (Montefluos S.p.A.) (number average molecular weight) M.W. =3200; kinematic viscosity=250 cSt (20°C.);
- Fomblin HC/R~ (Montefluos S.p.A.) M.W. =6600; kinematic viscosity=1500 cSt (20°C.);
- Galden D 03~ (Montefluos S.p.A.) M.W.=870; kinematic viscosity=2.4 cSt (25°C.);
- Galden D 10~ (Montefluos S.p.A.) M.W.=1320; kinematic viscosity=9 cSt (25°C.), all of them having the chemical structure:

CF3 [(O - CF - CFZ)" -(O - CFZ)m ] - OCF3 wherein n/m=20-40.
- Fomblin Z/25~ (Montefluos S.p.A.) M.W.=9400; kinematic viscosity=255 cSt (20°C.), having chemical structure:
CF3 [(O - CFZ - CFZ)P -(O - CFZ)q ] - OCF3 wherein p/q = 0. 6-0. 7.
- Fomblin M30~ (Montefluos S.p.A.) M.W. = 9400; kinematic viscosity=310 cSt (20°C.), having chemical structure like the one of Fomblin Z/25 with p/q=1.2.
- Krytox 1525~ (Du Pont) M.W.=4600; kinematic viscosity=261 cSt (20°C.), having chemical structure:

F (CFCF20) n - CFZCF3 wherein n=25-30.
- Demnum S-100~ (Daikin) M.W.=5600; kinematic viscosity=250 cSt (20°C.), having chemical structure:
F(CFZ CFZ CFZ O)~ CFZ CF3 wherein n=30-35.
These is dealt with trade names.
The stability was measured on the individual emulsions prepared in a centrifuge operating at 4000 r.p.m., during 1 hour, and then subjected to an ageing test at room temperature during 3 months on a shelf, then in an oven at 100°C.
during 1 week and at 180 °C. during 3 hours.

An emulsion was prepared by stirring in a Silverson L/2R turboemulsifier at 5000/6000 r.p.m. 20 parts of perfluoropolyether Fomblin HC/25 in 80 parts of glycerol, in the presence of 2 parts of emulsifying surfactant Texapon N40, solution at 28 % . It was operated as follows: the emulsifier was dissolved in glycerol and then the perfluoropolyether was added while stirring at room temperature for a few instants. An emulsion was obtained, which, subjected to the above-described stability tests, proved to be stable.

,...
_ 18 _ Examples 2-5 Example 1 was repeated under the same conditions and with the sane ingredients, but varying the amounts in the formulation as is indicated in the following Table 1 along with the results.

Example I Glycerol IFomblin HC/25 I Stability I I ( part s ) I ( art s ) 2 I 9o I to I yes I
I 3 ( 50 I 50 I
I
I 4 I 30 I 70 I ~~ I
~~

Examples 6-11 Examples 1 to 6 were repeated, but substituting Fomblin tiC,~R for Fomblin HC/25, thereby obtaining the resulis reported in the following Table 2.

I Example I Glycerol IFomblin HC/R I Stability I
I I ( parts ) I ( parts ) I I

6 I 90 I 10 I yes I

7 I 80 I 20 I ~~ I
I 8 I 70 I 30 ( ~~ I
9 I 50 I 50 I ~~ I
I 30 I 70 I ~~ I
11 I 25 I 75 I ~~ I

- lg - 20~v~~~
Examples 12-16 It was operated as is described in example 2, but varying the emulsifier amount as indicated in Table 3.

I Example I Glycerol IFomblin HC/25 Texapon N40 I
I

I I ( parts ) I ( part s ) I ( ~nrts ) I

I 12 I 90 I 10 I 0,5 I

I 13 . I " I " I 0.25 I

I 14 I " I " I 0,10 I

I 15 I " I " I 0,05 i (16 I " I " I 0.025 I

Stable emulsions were ob~ained.
Examples 17-20 Example 1 was repeated, but glycerol was substituted by the following polyhydroxylated compounds (poly-ols or saccharides) in aqueous solution, according to the formulations indicated in Table 4.

201300 ..

I I Polyhydroxylated IFomblin HC/25 Texapon N40 I
I

I Example) ~ compound ( I I

I I (parts) I (parts) ~ (parts) I

I 17 IMaltitol 90 I 10 I 0,025 ( I I (solu tion at 74%) ( I . I

I 18 ISorbitol 90 ( 10 I 2 I

I ((solution at 70%) ( I I

19 (Glucose 90 I 10 I '2 I

I ((solution at 70%) I I I

I 20 ISaccharose 90 I 10 I ((solution at 70%) I ~ I I

The emulsions obtained were stable.
Analogous results were obtained when using xylitol and man-nitol syrups.
Exar~pl es 21 -23 Example 1 was repeated, substituting other ionic emulsifiers for Texapon P~40, according to the formulations indicated in Table 5.

Example Glycerol Fomblin HC/25 Emulsifier (parts) (parts) 21 90 10 Amphisol K 0.25 (solid) 22 80 20 Nikkol ECTD-3NEX

(semisolid) 1 23 90 10 Benzalconium 25~

chloride K

(solution at 50 Stable emulsions were obtained.
Analogous results were obtained when using the following ionic surfactants:
Dehyton D; Texapon SB3 and Dehyton K.

Example 1 was repeated using the following formulation:
- Maltitol (solution at 74 % ) 40 parts Fomblin HC/25 20 parts - Dehyton K (solutin at 40 % ) 2 parts A stable emulsion was obtained.

Example 1 was repeated using the following formulations comprising a non-ionic emulsifier, according to Table 6.

I Examale I Glycerol IFomblin HC/25 I Emulsifier I
I I ( parts ) I ( parts ) I ( paLrt s) I
I 25 I 90 I 10 ITween 20 1 I
I 26 I 90 I 10 IEmulgin B1 2 I
Shelf-stable emulsions were obtained.
Examples 27-32 Example 1 was repeated but substituting other per-fluoropolyethers for Fo~blin HC/25, according to the form-ulations indicated in Table 7.

I Glycerol (Texapon N40 IPerfluoropolyether~

Example ( part s) I ( part s) I ( parts ) I

I 27 I 90 I 2 ( Demnum S/100 2 I 28 I 90 I 2 I Krytox 1525 10 29 I 90 I 1 I Galden D03 10 I

I 30 I 74 I 1 I Galden 010 25 i I 31 ( 90 I 2 I Fomblin Z/25 10 I

( 32 I 90 I 2 ( Fomblin 30M 10 I

Stable emulsions were obtained.
examples 33-36 Example 1 was repeated, according to the formulations indicated in Table 3.

2~~

I Exam;~le I Glycerol IFomblin HC/25 Texapon N40 I
I

( parts ) ( ( parts ) I ( parts ) ( 33 I 38 ( 60 I 2 I

Stable emulsions were obtained.
Exar~pl a 37 Example 1 was repeated, according to the following formulation:
- t~altitol 58 parts - Fomblin HC/25 40 "
- Texaaon ";40 2 (solution at 28a).
A stable emulsion was obtained.
Example 38 Example 1 was repeated, a c c o r d i n g t o t h a f o 1 1 o w i n g formulation:
- di-glycerol 70 parts - Fomblin HC/R 2g ~~
- Texapon N40 2 ~~
a stable emulsion was obtained.

-23a-It was operated as in Example 1, according to the following formulation:
- glycerol 50 parts - propylene glycol 28 parts - Fomblin HC/25 20 parts - Texapon N40 2 parts a stable emulsion was obtained.

Preparation of Creams According to the Perfluoropolyether Pre-Emulsification Technology Hydrating cream ( % by weight) PEG-8~ C,z_,$ alkyl ester 6.0 PEG-20~ methyl-glucose sesquistearate 1.2 Isoporpyl stearate 5.0 Cetyl alcohol 3.0 Stearic acid 1.0 Octyl stearate 6.0 Alc~ond of l 2.0 Antioxidants as sufficient b) lJater, oalance to 100,0 Natural hydrating factors 1.0 c) Emulsion (example 1) 4:0 d) Perfume, preserving agents and sequestering agents as sufficient Procedure The emulsion of Fomblin HC/25 in glycerol, as specified in example 1,(c), was utilized.
a) and b) were separately heated to 75°C. b) was added to a) under stirring.
Emulsion c) was added at room temperature, stirring was car-ried on and d) was added.
A centrifugation-stable cream was obtained, in which Fomblin HC/25 was present in a finely dispersed form (below 1 mi-crony.
Example 41 Sun emulsion (% by weight) a) Stearic acid 4.0 Cetyl alcohol 1.0 Caprylic acid/capric acid ester-ified with coco alcohol 6.0 Tocopherol acetate 2.5 Dimethicone 0.3 Octyl methoxycinnamate 6.0 Butylmethoxybenzoyl methane 1.5 b) Potassium cetyl phosphate (Amphisol K) 2.0 c) Potassium hydroxide 0.15 0.15 Pantenol (aminoalcohol) 2.0 d) Gelling agent (acrylic polymer:

Carbomer 940)~ as sufficient Water, balance to 100.0 e) Emulsion (example 1) 7.0 f) Perfume, sequestering agents and preserving agents as sufficient Procedure a) was heated to 85°C. in a (planetary type) mixer, then b) was added.
After a homogeneous solution was obtained, c), preheated to 75°C., was added and mixing was continued. The whole was allowed to cool to 40°C. d) was added.
The emulsion of Fomblin HC/25 in glycerol, as specified in example 1 (e), was utilized.
e) was added under stirring until reaching the room temperature. f) was then added.

2~~~

Barrier cream (% by weight) a) PEG-8 C12-1B alkyl ester 10.0 Glyceryl stearate and PEG-100 stearate 3.0 Octyl stearate 10.0 Cetyl alcohol 3,0 b) Mater, balance to 100.0 c) Er;~ulsion (example 9) 6.0 d) Perfume, areserving agents and sequestering agents as sufficient The emulsion of Fomblin HC/R in glycerol, as specified in example 9 (c), was utilized.
a) and b) v~ere heated separately to 75°C. b) was added to a) under stirring.
At room temperature (or indifferently also in hot conditions) emulsion c) was added. Stirring was carried on and d) was ad-ded.
Example 43 Antiwrinkle cream based on retinol (% by weight) a) Cetylstearylic alcohol 12 OE 1.5 Cetylstearylic alcohol 20 OE 1.5 Stearic acid mono-diglyceride 10.0 Cetylstearylic alcohol 2,0 Caprylic/capric acids triglyceride 6.0 Acetylstearyl isononanoate 5.0 _ 27 _ Silicone oil 350 cps 0.5 Retinol palnvtate 1,000,000 UI/mL 1.0 Antioxidants as sufficient b ) tJa ter, bal ance to 1 00.0 c) Emulsion (example 1) 7.0 d) Perfume, preserving agents and seques-tering agents as sufficient The aqueous phase and the oily phase were heated separately to 75°C, emulsifying them by means of a turbine an~f cooling them under stirring. The thermolabile components, the Fom-blip emulsion and the perfume were added at 40°C, and mix-ing was carried on until reaching the room temperature.

Claims (22)

1. Stable emulsions of perfluoropolyethers having perfluoroalkyl end groups, consisting of:
a) from 0.1 to 75% by weight of a perfluoropolyether;
b) from 0.01 % to 5% of a surfactant; and c) from 20% to 99.89% of glycerol.

2. Stable emulsions of perfluoropolyethers having perfluoroalkyl end groups, consisting of:
a) from 0.01 % to 50% by weight of a perfluoropolyether;
b) from 0.01 % to 5% of a surfactant; and c) from 45% to 99.98% of a solution in a hydrophilic solvent of a polyhydroxylated compound selected from the group consisting of polyalcohols other than glycerine and the saccharides containing at least three hydroxylic groups, said hydrophilic solvent being selected from the group consisting of glycols, glycerol, lower alcohols, ethers, diglymes and mixtures thereof.

3. The emulsions according to claim 1 or 2, wherein the perfluoropolyether is selected from the group consisting of the perfluoropolyethers containing one or more of the following repeating perfluorooxyalkylene units:
a) (CF2-CF20) b) (CF2O) c) d) (CF2O-CF2-CF2O) e) (CF2-CF2-CF2O) f) and g) wherein groups Rf'~, like or different from one another, are a fluorine atom or a perfluoroalkyl group.

4. The emulsions according to claim 1 or 2, wherein the perfluoropolyether is selected from the group consisting of perfluoropolyethers containing the following perfluorooxyalkalene units either singly or combined with one another:
I) (CF2-CF2O) and (CF2O), said units being statistically distributed along the perfluoropolyether chain;
and CFXO
wherein X is F or CF3, said units being statistically distributed along the chain;
and CFXO
wherein X is F or CF3, said units being statistically distributed along the chain;

IV) V) (CF2-CF2-CF2O);
VI) (CF2-CF2O);

wherein groups Rf~ are the same or different and represent a fluorine atom or a perfluoroalkyl group and VIII) (CF2O-CF2-CF2-O).

5. The emulsions according to claim 1 or 2, wherein the perfluoropolyether is selected from the group consisting of perfluoropolyethers containing perfluorooxetane rings of the formula:
wherein T, B and R, are the same or different from one another, and are selected from the group consisting of a perfluorooxylalkyl, perfluoropolyoxylalkyl and perfluoroalkyl radicals and A is selected from the group consisting of a perfluorooxyalkyl, perfluoropolyoxyalkyl and perfluoroalkyl radical.

6. The emulsions according to claim 1 or 2, wherein in the perfluoropolyether is selected from the group consisting of perfluoropolyethers belonging to the following classes:
wherein R f and R' f are alike or different from each other, are selected from the group consisting of CF3, C2F5 and C3F7; units C3F6O
(oxytrifluoromethyltrifluoroethylene), and CF2-O being statistically distributed along the chain; a is an integer;
be and c are integers or zero; when the sum (b+c) is other than zero, the ratio ranges from 5 to 40;
B) CF3O-(C2F4O)d(CF2O)e-CF3 wherein units C2F4O and CF2O are statistically distributed along the chain;
d and a are integers; the d/e ratio ranges from 0.3 to 5;
C) CF3O-(C3F6O)f(C2F4O)g(CFXO)h-CF3 wherein units C3F6O, C2F4O and CFXO are statistically distributed along the chain;
X is F or Ch3;
f, g and h are integers;
the ratio ranges from 1 to 50, and the g/h ration ranges from 1 to 10;
D) R3fO-(CF2CF2O)jR4f wherein R3f and R4F, like or different from each other, are -CF3 or -C2F5 and j is an integer.

7. The emulsions according to claim 1 or 2, wherein the perfluoropolyether has a number average molecular weight ranging from 500 to 20,000.

8. The emulsions according to claim 1 or 2, wherein the perfluoropolyether has a number average molecular weight ranging from 1,000 to 10,000.

9. The emulsions according to claim 1 or 2, wherein the surfactant is selected from the group consisting of cationic anionic, amphoteric and non-ionic emulsifiers.

10. The emulsion according to claim 2, wherein polyalcohols other than glycerine are selected from the group consisting of polyalcohols containing from 3 to 12 carbon atoms and the saccharides are selected from the group consisting of saccharides containing from 4 to 18 carbon atoms and mixtures thereof obtained from hydrolytic demolition of polysaccharides.

11. The emulsion according to claim 2 wherein the polyhydroxylated compound is selected from the group consisting of xylitol, mannitol, sorbitol, glucose, maltitol, saccharose, fructose, di-glycerol, triglycerol and tetraglycerol.

12. The emulsion according to claim 2, wherein the solution of the polyhydroxylated compound in the hydrophilic solvent has a concentration from 50% to 80% by weight of polyhydroxylated compound.

13. Stable emulsions of perfluoropolyethers having perfluoroalkyl end groups, consisting of:
a) from 0.01% to 50% by weight of a perfluoropolyether;
b) from 0.01% to 5% of a surfactant; and c) from 45 to 99.98% of a solution in water of a polyhydroxylated compound selected from the group consisting of polyalcohols other than glycerine and the saccharides containing at least three hydroxylic groups;

i) said solution in water is a syrup (a concentrated solution) containing 50 to 80% by weight of the polyhydroxylated compound;
ii) the polyhydroxylated compounds are crystalline powders soluble in water;
iii) the surfactant is an ionic surfactant or emulsifier used for cosmetics.

14. The emulsions according to claim 13, wherein the perfluoropolyether is selected from the group consisting of perfluoropolyethers containing one or more of the following repeating perfluorooxyalkylene units;
a) b) (CF20);
c) d) (CF2O-CF2 CF2O);
e) (CF2-CF2-CF2O);
f) and g) wherein the group R f"' are alike or different, and are a fluorine atom or a perfluoroalkyl group.

15. The emulsions according to claim 13, wherein the perfluoropolyether is selected from the group consisting of perfluoropolyethers containing the following perfluorooxyalkylene units either singly or combined with one another;

I) (CF2 and CF2O) and (CF2O), said units being statistically distributed along the perfluoropolyether chain;
wherein X is F or CF3, said units being statistically distributed along the chain;
wherein X is F or CF3, said units being statistically distributed along the chain;
V) (CF2-CF2-CF2O);
VI) (CF2-CF2O);
wherein groups R f'", are the same or different and represent a fluorine atom or a perfluoroalkyl group and VIII) (CF2O-CF2-CF2-O).

16. The emulsions according to claim 13, wherein the perfluoropolyether is selected from the group consisting of perfluoropolyethers containing perfluorooxetane rings of the formula:
wherein T, B and R, are the same or different from one another, and are selected from the group consisting of a perfluorooxylalkyl, perfluoropolyoxylalkyl and perfluoroalkyl radicals and A is selected from the group consisting of a perfluorooxyalkyl, perfluoropolyoxyalkyl and perfluoroalkyl radical.

17. The emulsion according to claim 13 wherein the perfluoropolyether is selected from the group consisting of A) wherein R f and R'f are alike or different from each other, are selected from the group consisting of CF3, C2F5 and C3F7; units C3F6O
(oxytrifluoromethyltrifluoroethylene), and CF2-O being statistically distributed along the chain; a is an integer;
be and c are integers or zero; when the sum (b+c) is other than zero, the ratio a/b + c is from 5 to 40;

B) CF3O-(C2F4O)d(CF2O)c-CF3 wherein units C2F4O and CF2O are statistically distributed along the chain;
d and e are integers; the d/e ratio ranges from 0.3 to 5;
C) CF3O-(C3F6O)f(C2F4O)g(CFXO)h-CF3 wherein units C3F6O, C2F4O and CFXO are statistically distributed along the chain; X is F or CF3; f, g and h are integers; the ratio f/g+h is from 1 to 50, and the ratio g/h is from 1 to 10;
D) R3f O-(CF2CF2O)j R4f wherein R3f and R4F, like or different from each other, are -CF3 or -C2F5 and j is an integer.

18. The emulsion according to claim 13 wherein the perfluoropolyether has a number average molecular weight ranging from 500 to 20,000.

19. The emulsions according to claim 13, wherein the perfluoropolyether has a number average molecular weight ranging from 1,000 to 10,000.

20. The emulsion according to claim 13, wherein the polyalcohols other than glycerine are selected from the group consisting of polyalcohols containing from 3 to 12 carbon atoms and the saccharides are obtained from the hydrolytic demolition of polysaccharides and contain from 4 to 18 carbons and mixtures thereof.

21. The emulsions according to claim 13, wherein the polyhydroxylated compound is selected from the group consisting of xylitol, mannitol, sorbitol, glucose, maltitol, saccharose, fructose, di-glycerol, triglycerol and tetraglycerol.

22. The emulsion according to claim 13, wherein the surfactant is selected from the group consisting of cationic, anionic and amphoteric emulsifiers.