Organic compounds -- part of the class 532-570 series – Organic compounds – Silicon containing
Patent
1993-01-07
1995-04-04
Shaver, Paul F.
Organic compounds -- part of the class 532-570 series
Organic compounds
Silicon containing
C07F 708
Patent
active
054039444
DESCRIPTION:
BRIEF SUMMARY
This invention is concerned with novel organosilicon compounds which are effective in absorbing ultra violet radiation and is also concerned with a process of preparing such compounds.
A number of organic compounds, generally organic acids and derivatives thereof, are known to be chromophores having U.V.-absorbing properties and are employed on a commercial scale as ingredients in sunscreen preparations or as plastic additives. Although such materials function adequately they are easily removed from the substrate to which they have been applied. For example, cosmetic sunscreen preparations can be removed during bathing thus requiring repeated applications if protection is to be maintained. It is also desirable that the active ingredient remain on the surface of the skin rather than penetrate into or through the skin.
Compounds which overcome this problem to a certain extent are disclosed for example in European Patent Specification 305 059, which provides organosilicon compounds having at least one unit of the general formula ##STR1## any other units present in the said siloxanes being those represented by the general formula ##EQU3## wherein R represents a C.sub.1-18 alkyl group, R' is a divalent alkylene or oxyalkylene group having from 2 to about 20 carbon atoms, or a divalent alkenylene or oxyalkenylene group having from 2 to 20 carbon atoms, wherein the carbon-carbon double bond is adjacent to the silicon atom, R" is a halogen atom, an alkyl, aryl, alkoxy or alkoxyalkoxy group having less than 9 carbon atoms, Q represents a hydrogen atom, a monovalent C.sub.1-18 hydrocarbon or halogenated hydrocarbon group, Z is an alkyl or an alkoxy group having from 1 to 8 carbon atoms or a hydroxyl group, a and b each have a value of 0, 1, 2 or 3 and c is 0 or 1, provided that at least one of Z and R' is linked to the multivalent aryl group via an ether linkage.
It was found, however, that although the materials described above were, in comparison with the prior art, less susceptible to hydrolysis at the ester linkage, for example by enzymatic hydrolysis on the skin when these materials were used as cosmetic sunscreen agents, they were not sufficiently photostable when exposed to UV irradiation.
EP publication 392 882 discloses the use of diorganopolysiloxanes with a benzalmalonate functionality in cosmetic applications. The diorgano-polysiloxanes which are useful in said application have the average general formula ##STR2## wherein R is C.sub.1-10 alkyl, phenyl or trifluoropropyl, B is R or A, r is from 0 to 200, s is from 0 to 50, u is from 1 to 20, t is from 0 to 20, t+u is at least 3, there being at least one group A per molecule and A denotes a structure of the general formula ##STR3## wherein R.sup.1 is H, OH, trimethylsiloxy, C.sub.1-6 alkoxy or a divalent group --(O).sub.n --(CH.sub.2).sub.p --CH(R")--CH.sub.2 --, n is 0 or 1, p is 1 to 10, R" is H or C.sub.1-4 alkyl, R.sup.2 is H, C.sub.1-6 alkyl or C.sub.1-6 alkoxy, R.sup.3 is C.sub.1-8 alkyl, at least one of the R.sup.1 groups being the divalent group.
We have found that although the materials described in both above identified references perform well in many applications, and although there is a reduction in the amount of chromophore which penetrates through the skin when applied thereto in comparison with the amount of chromophore which penetrates when it has been applied as a pure compound (i.e. not linked to an organosilicon compound), there is still a need to further reduce the amount of penetration through the skin.
We have now found that if certain novel chromophores are used in the preparation of organosilicon compounds, improved cosmetic preparations, effective in absorbing ultra violet radiation can be obtained.
According to a first aspect of the invention there is provided an organosiloxane compound having at least one unit of the general formula ##EQU4## any other units present in the said siloxanes being those represented by the general formula ##EQU5## wherein R represents a C.sub.1-8 alkyl or an aryl group, R.sup.1 is a hydrogen atom or a
REFERENCES:
patent: 3718681 (1973-02-01), Adams
patent: 3962299 (1976-06-01), Stackman
patent: 4176124 (1979-11-01), Darms et al.
patent: 4924020 (1990-05-01), Okawa et al.
patent: 4992261 (1991-02-01), Colas et al.
patent: 5053290 (1991-10-01), Canivenc et al.
patent: 5077422 (1991-12-01), Colas et al.
patent: 5138012 (1992-08-01), Riding et al.
Frater Georg
Schwarzenbach Rolf
Van Oycke Stephane F. M.
Givaudan-Roure Corporation
Gould George M.
Johnston George W.
Shaver Paul F.
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