CA1039655A - Cosmetic base and composition - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
A cosmetic base comprising the saturated hydrocarbons prepared by subjecting a synthetic polyisoprene rubber to a thermally destructive distillation under a reduced pressure, fractionally distilling the distillate to recover a fraction boiling at 155 to 240°C/l mmHg, and catalytically reducing the fraction,and cosmetic composition containing the cosmetic base.

Description

-~03965S

1 Field of the Invention ' The present invention relates generally to an excellent cosmetic and more particularly it relates to a cosmetic con-taining as the base the saturated hydrocarbons obtained from a synthetic polyisoprene rubber.
An object of this invention is to provide an excellent base for cosmetics, which can be used in place of natural squalane.

2. Description of the Prior Art ,~ .
Squalane is obtained by reducing squalane which is recovered from shark liver oil, etc., and is widely used as bases for cosmetics. However, since natural squalane has a specific odor, which increases in strength during the storage of the material degrading the quality of cosmetic, and since it is a natural product the supply varies widely, the discovery of substitutes for squalane has been desired.
A process of producing a substitute for squalane by polymerizing dipentene is disclosed in the specification of Japanese Patent Publication No. 11,446/'63 but the yield of the polymer obtained by the process is only about 24~ to the raw material dipentene and thus such a process is economically dis-advantageous.

SUMMARY OF THE INVENTION

Therefore, various investigations for discovering a -substitute for squalane have been made and as the result thereof it has been discovered that the saturated hydrocarbons obtained by reducing the hydrocarbons formed by the thermal decomposition of a synthetic polyisoprene rubber have properties similar to ~39655 1 that of squalane and also are quite excellent as bases for cosmetics and that in addition these saturated hydrocarbons are obtained with a high yield of about 65%.
Therefore, according to the present invention there is provided a cosmetic base comprising the saturated hydrocarbons prepared by subjecting a synthetic polyisoprene rubber to a thermally destructive distillation under a reduced pressure, -~
fractionally distilling the distillate thus obtained to provide a fraction boiling at 155 to 240C/l mmHg, and then catalytically reducing the fraction and a cosmetic composition including the cosmetic base.

DETAILED DESCRIPTION OF THE INVENTION

A synthetic polyisoprene rubber is a synthetic rubber similar to natural rubber and having 92 to 97% cis-type double bonds prepared by polymerizing isoprene in the presence of a Ziegler catalyst or a lithium-type catalyst and recently such a synthetic polyisoprene rubber has become commercially available easily and at a low cost.

It is well known that low-polymer hydrocarbons are obtained by thermally decomposing natural rubber and, in particular, as a method of thermally decomposing natural rubber under a reduced pressure, a method is reported in which natural rubber is subjected to a thermally destructive distillation under a pressure of 0.1 mmHg to provide a distillate fraction in an amount of 63.5% and a resinous material in an amount of 36.5~ as disclosed in Staudinger & Fritschi; Helv. Chim. Acta.;
Vol. 5, 785 (1922). :
The thermal decomposition of natural rubber has also been investigated and almost the same results as those obtained by Staudinyer et al have been obtained. That is, by the thermal ~039655 1 decomposition, a distillate in an amount of 60% and a resinous material in an amount of 40% were obtained but the content of the hydrocarbons having 25 to 35 carbon atoms in the dis-tillate was only 20%. Furthermore, the hydrocarbons have a bad odor caused by impurities such as protein, etc., contained in the natural rubber raw material and the removal of the bad odor -was quite difficult. On the other hand, it has been found that when a synthetic polyisoprene rubber is thermally decomposed, the product is composed of almost 100% distillate and contains almost no resinous material, the content of the hydrocarbons having 25 to 35 carbon atoms in the;distillate is about 65%, the hydrocarbons have less of a bad odor, and further the reduction product of the hydrocarbons is a colorless oil having a fragrance and have no unstable color and odor as is the ~
situation with natural squalane. -The polyisoprene rubber as used in this invention has 92 to 97% cis-type double bonds, has a degree of polymerization of about 220,000 and has the following general formula for ~-repeating units contained in the polyisoprene rubber;

IC 3 ;
[ CH2 - C = CH - CH2 ]n wherein n is about 220,000. Typical commercial examples of the synthetic polyisoprene rubber are"IR2200", which is a common trademark of Japan Synthetic Rubber Co., Ltd., Kuraray Co., Ltd., Nippon Zeon Co., Ltd., etc. The synthetic polyisoprene rubber can be prepared as described in F.W. Stravely, Industrial and Engineering Chemistry 48, No. 4, 778-783 (1956), etc. by poly-merizing isoprene in the presence of a Ziegler type catalyst or a lithium-type catalyst.

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1'039655 1 The saturated hydrocarbons used in this invention can be obtained using the process described in Canadian patent application serial number 213,438, filed on November 12, 1974, :.
in which small pieces of synthetic polyisoprene rubber are uniformly heated to temperatures of about 300 to 400C, preferably 340 to 350C, under a pressure of about 0.1 to 5 mmHg, preferably 0.1 to 1.0 mmHg. The thermally distructive distillation can be suitably accomplished for about 30 minutes at about 350C when 1 kg of the starting material rubber is used. Then, by distllling the distillate thus obtained and collecting a fraction boiling at 155 to 240C/l.mmHg, hydrocarbons having about 25 to 35 carbon atoms are obtained. Subsequently, by catalytically reducing the hydrocarbons under normal pressure-or at high pressure using hydrogen in the presence of a catalyst such as palladium, nickel, platinum, etc., using a conventional catalytic reduction method, the saturated hydrocarbons are obtained. The catalytic reduction is generally conducted at about room temperature (e.g., 20 to 30& ) to about 300C. When palladium and platinum are used as catalyst, a suitable temperature generally 20 ranges from about room temperature to about 100C, and, when :
nickel is used as catalyst, a suitable temperature generally ranges from about 100 to about 300Cj preferably about 250C. .
A suitable amount of the catalyst generally ranges from about 3 to 10% by weight based on the raw materials. When nickel is used as a catalyst, the reaction generally is completed in about 5 to 10 hours at about 250C.
The detailed chemical structures of the saturated hydro-carbons have not yet been determined but are as.sumed to have structures similar to chain terpene compounds formed by the 1,4-bond of isoprene. Moreover, since squalane is a chain terpene ~ .
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1(039655 1 compound having isopropyl groups at the both ends of the molecule, it may be considered that the properties of the saturated hydrocarbons quite resemble the properties of squalane but as the result of experiments, it has been confirmed that the saturated hydrocarbons are similar to squalane in fluidity as a base for cosmetics, but in addition the oily feeling, solubility and emulsification are superior to squalane in the point that they exhibit no irritation to skin and that they are quite stable. Also, the saturated hydrocarbons used in this invention are stable as to raw material sources and cost and the industrial significance as the bases for cosmetics is quite important. For example, the cosmetic base of this invention can be widely employed as an oil base in compositions such as cold creams, tissue creams, hygienic creams, nourishing creams, hand creams, massage creams, modern face creams, cleansing creams, shaving creams, after-shaving creams, sunburn preventives, sun tan oils, -lipsticks, foundation sticks, etc. It is to be emphasiæed that the utility of the cosmetic base of this invention is not limited to these examples.
The properties of the saturated hydrocarbons used in this invention are shown in the following table together with those of squalane.

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Property Saturated Saturated Squalane Hydrocarbon Hydrocarbon (mainly C30) (C25 C35) Boiling Point (1 mmHg) 195-215 155-240 205-215 Gravity ( 20) 0.8988 0.8729 0.8106 Freezing Point * about -70C about -70C about -55C

Iodine Value 0 0 0 (*): Simple measurement in an acetone-dry ice bath.

1~3965S
1 The following reference example shows an embodiment of the process of producing the saturated hydrocarbons used in this invention.
REFERENCE EXAMPLE

In a decomposition flask were charged 100 g of small pieces of a synthetic polyisoprene rubber and after displacing the inside atmosphere of the flask with nitrogen and evacuating the flask, the polyisoprene rubber was heated to 340 to 350C

under a pressure of 0.1 mmHg, whereby the deccmposition began in 17 minutes and 100 g of a decomposed oil was obtained 13 minutes later. In this case almost no residue was observed in the flask. By fractionally distilling the decomposed oil under a reduced pressure, 65 g of a fraction boiling at 155 to 240C/l mmHg was obtained. The fraction thus obtained was subjected to a hydrogenation in an autoclave at a temperature of 100C and at a hydrogen pressure of 100 kg/cm2 in the presence of 10 g of Raney nickel. The hydrogenation was finished after two hours. Then, the hydrogenated oil was cooled, with-drawn from the autoclave, and after removing the catalyst by 20filtration, was distilled under a reduced pressure to provide 63 g of saturated hydrocarbons. The properties of these hydro-carbons were the same as those shown in Table 1.
The invention is illustrated in greater detail by reference to the following examples.

Preparation of Cold Cream (w/o type) %
Beeswax 12.0 Lanolin 3.0 Vaseline 10.0 Saturated Hydrocarbons of This Invention 38.0 Solid Paraffin 7.0 1~39655 1 Sorbitan Sesquioleate 3.8 Polyoxyethylene Sorbitan Sesquioleate 0.2 Distilled Water 25.5 Perfume 0.5 Antioxidant and Antiseptic Suitable amounts Distilled water was heated to 70C. A mixture of the -other components shown above was melted by heating and maintained at 70C. Distilled water was gradually added to the molten mixture and emulsified. Then, the mixture was cooled under stirring, placed in a vessel at 40C and allowed to cool to provide a cold cream. -Preparation of Foundation Stick:
% ~:~

Saturated Hydrocarbons of This Invention 25.0 Carnauba Wax 7.0 Solid Paraffin lO.0 Isopropyl Myristate 5.0 Sorbitan Sesquioleate 3.0 Powdered Coloring Matter 50.0 Perfume Suitable amounts Antioxidant Suitable amounts -The saturated hydrocarbons of this invention were mixed with isopropyl myristate and after adding thereto sorbitan sesquioleate and the powdered coloring matter, the mixture was mixed well. A mixture of carnauba wax and solid paraffin was melted by heating and after uniformly dispersing the oily mixture prepared above in the molten mixture, the mixture was stirred well and solidified by quenching in a mold to provide a foundation stick.

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~39f~55 Preparation of Sun Tan Oil:
Saturated Hydrocarbons of This Invention 60 Olive Oil 37 Ultraviolet Absorbent 3 Antioxidant Suitable amounts Perfume Suitable amounts These components were mixed well to provide a sun tan oil.
While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skillèd in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.

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Claims (5)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A cosmetic base comprising the saturated hydrocarbons prepared by subjecting a synthetic polyisoprene rubber to a thermally destructive distillation under a reduced pressure, fractionally distilling the distillate thus obtained to provide a fraction boiling at 155 to 240°C/l mmHg, and then catalytically reducing the fraction with hydrogen, said saturated hydrocarbons having a boiling point at a temperature of between 155° and 240°C/l mmHg and having an iodine value of 0.

2. A cosmetic composition including as a cosmetic base the cosmetic base as claimed in claim 1.

3. The cosmetic composition as claimed in claim 2, wherein said cosmetic composition is a cold cream.

4. The cosmetic composition as claimed in claim 2, wherein said cosmetic composition is a foundation stick.

5. The cosmetic composition as claimed in claim 2, wherein said cosmetic composition is a sun tan oil.