U.S. patent application number 09/916560 was filed with the patent office on 2001-12-27 for coal tar extract with a reduced content of hydrocarbons and dermatological and cosmetic compositions containing the same.
Invention is credited to Navarro, Roger.
Application Number | 20010054574 09/916560 |
Document ID | / |
Family ID | 9504586 |
Filed Date | 2001-12-27 |
United States Patent
Application |
20010054574 |
Kind Code |
A1 |
Navarro, Roger |
December 27, 2001 |
Coal tar extract with a reduced content of hydrocarbons and
dermatological and cosmetic compositions containing the same
Abstract
The invention concerns a coal tar extract with reduced
polycyclic aromatic hydrocarbon content and a method for obtaining
same using two sequentially linked distillation systems. The
invention also concerns cosmetic and dermatological preparations
containing said resulting coal tar extract.
Inventors: |
Navarro, Roger; (Pamiers,
FR) |
Correspondence
Address: |
THE FIRM OF HUESCHEN AND SAGE
500 COLUMBIA PLAZA
350 EAST MICHIGAN AVENUE
KALAMAZOO
MI
49007
US
|
Family ID: |
9504586 |
Appl. No.: |
09/916560 |
Filed: |
July 27, 2001 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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09916560 |
Jul 27, 2001 |
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09380958 |
Sep 10, 1999 |
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Current U.S.
Class: |
208/401 ;
424/400; 424/401 |
Current CPC
Class: |
A61K 35/04 20130101;
A61K 8/9767 20170801; A61Q 19/00 20130101; A61Q 5/006 20130101;
B60K 15/05 20130101; Y10S 514/88 20130101; C10C 3/06 20130101; Y10S
514/861 20130101; Y10S 514/863 20130101; Y10S 514/881 20130101;
Y10S 514/864 20130101; C10C 1/16 20130101; A61K 8/9794 20170801;
A61K 8/9789 20170801 |
Class at
Publication: |
208/401 ;
424/400; 424/401 |
International
Class: |
C10G 001/00; A61K
007/00 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 11, 1997 |
FR |
97 02835 |
Claims
1. Coal tar extract, characterized in that its maximum content of
polycyclic aromatic hydrocarbons is about ten parts per million
(ppm) and its maximum content of benzo(a)pyrene is about a few
ppm.
2. Coal tar extract according to claim 1, characterized in that its
content of polycyclic aromatic hydrocarbons is less than about 4
ppm and its content of benzo(a)pyrene is less than about 1 ppm.
3. Process for obtaining a coal tar extract according to claim 1 or
2, from crude coal tar, characterized in that it uses at least two
distillation systems connected in series.
4. Process according to claim 3, characterized in that the first
system is a thin-film evaporator and/or the second system is a
distillation column.
5. Process according to claim 4, characterized in that the
distillation on a thin-film evaporator is carried out under a
pressure of 5 to 7 mmHg, between 198.degree. C. and 200.degree. C.,
and at a crude coal tar feed rate equal to 18 to 19 kg/h.
6. Process according to claim 5, characterized in that the
distillation on a distillation column following distillation on a
thin-film evaporator is carried out at from 260.degree. C. to
320.degree. C.
7. Cosmetic or dermatological compositions containing a coal tar
extract according to claim 1 or 2 or obtained by the process
according to one of claims 3 to 6.
8. Cosmetic or dermatological compositions according to claim 7,
characterized in that they contain 0.1 to 10% by weight of coal tar
extract.
Description
[0001] The present invention relates to a coal tar extract with a
reduced content of polycyclic aromatic hydrocarbons, to a process
for obtaining it and to dermocosmetic compositions containing
it.
[0002] The term "coal tar" means the by-product of the destructive
distillation of bituminous coal distilling between at 300 and
370.degree. C. This is a black viscous liquid whose characteristic
odor resembles that of naphthalene.
[0003] The term "coal pitch" means the residue from the
distillation of coal tar.
[0004] Crude coal tar contains a large proportion of polycyclic
aromatic hydrocarbons (PAH) of the order of 100,000 ppm. Among the
predominant PAHs which have been identified are fluoranthene,
pyrene, anthracene, phenanthrene, fluorene, 1,2-benzofluorene,
2,3-benzofluorene, 1,2-benzanthracene, chrysene,
benzo(k)-fluoranthene, benzo(a)fluoranthene, benzo(b)fluoranthene,
benzo(e)pyrene, benzo(a)pyrene (BaP), indeno(1,2,3,c,d)pyrene,
1,2,5,6-dibenzanthracene, benzo(6)chrysene and
benzo(g,h,i)perylene, the last thirteen compounds having toxic
properties.
[0005] Coal tar is commonly used in antidandruff treatment, in the
treatment of certain types of dermatitis such as eczema,
lichenification and psoriasis. Before being incorporated into
dermatological compositions, coal tar undergoes a purification
intended to make it colorless, odorless and substantially free of
irritant properties.
[0006] Many processes for purifying coal tar are described in the
literature.
[0007] Patent U.S. Pat. No. 3,766,052 (Warner Lambert Co.)
published on Oct. 16, 1973 describes a process for purifying
commercially available coal tar, which comprises mixing the said
coal tar with a C.sub.15-C.sub.22 fatty acid ester, adding squalane
or squalene, and recovering the purified coal tar in the form of
the supernatant liquid. The coal tar obtained has a viscosity of
between 10 and 50 mPa.s and a density at 25.degree. C. of between
0.88 and 0.95. It is used as an active ingredient in dermatological
compositions in a proportion from 1 to 10% by weight.
[0008] Patent U.S. Pat. No. 3,928,579 (Warner Lambert Co.)
published on Dec. 23, 1975 describes a process for purifying crude
coal tar, which consists:
[0009] 1) of an extraction with a volatile solvent or mixture of
solvents whose kauri butanol number is less than 75 and whose
boiling point is less than 80.degree. C.,
[0010] 2) of a filtration, and then
[0011] 3) of an evaporation of the volatile solvent(s).
[0012] The solvents used are C.sub.3-C.sub.6 alkanes or CFCs.
[0013] The purified coal tar is incorporated in the dermatological
composition.
[0014] Patent application JP-55 153 710 (Fujunaga Seiyaku)
published on Nov. 30, 1980 describes a cosmetic skin composition
containing, as active ingredient, purified tar obtained by
distillation of mineral, animal or plant tar under reduced
pressure, by diazotization and then by hydrolysis or heating. The
tars used are coal tar and soybean tar.
[0015] The distillation carried out from 50 to 120.degree. C. under
a vacuum of 5-10 mmHg allows the mutagenic properties of the tar to
be reduced by a factor of 20. Diazotization with an excess of
nitrite followed by an increase in temperature and optionally a
hydrolysis makes it possible to reduce the mutagenic properties of
the tar by a factor of 90.
[0016] Among the PAHs contained in coal tar whose toxic properties
have been recognized, it has been found that BaP exhibits
carcinogenic properties in the event of prolonged use.
[0017] Patent application EP-A-465,434 describes tar oil obtained
by fractional distillation of naphthalene oil on three
rectification columns in series between 230 and 330.degree. C. The
naphthalene oil itself is obtained from the distillation of coal
pitch.
[0018] At the experimental stage, this extract can contain a BaP
percentage of less than 2 ppm (parts per million). However, at the
industrial scale, a BaP percentage of about 20 ppm will be
selected.
[0019] The present invention relates to a coal tar extract with a
reduced content of both PAH and BaP.
[0020] The coal tar extract according to the invention is
characterized by a maximum PAH content of about ten ppm and by a
maximum BaP content of about a few ppm.
[0021] The coal tar extracted according to the invention is
preferably characterized by a PAH content of less than about 4 ppm
and a BaP content of less than about 1 ppm.
[0022] The present invention also relates to a process for
obtaining the said coal tar extract from crude coal tar which uses
at least two distillation systems connected in series.
[0023] A thin-film evaporator is advantageously chosen as the first
distillation system, and/or a distillation column as the second
system.
[0024] The distillation on a thin-film evaporator is carried out
under a pressure of 5 to 7 mmHg, at a temperature of between 198
and 200.degree. C., and at a crude coal tar feed rate equal to 18
to 19 kg/h.
[0025] The column distillation following distillation on a
thin-film evaporator is carried out at between 260 and 320.degree.
C.
[0026] The distillation yield according to the invention using a
thin-film evaporator coupled to a distillation column is between 20
and 25% by weight.
[0027] Crude coal tar is commercially available and corresponds to
the definition in the French Pharmacopea and/or in the US
Pharmacopea. Its respective contents of PAH and of BaP are about
93,000 and 2000-10,000 ppm.
[0028] The present invention relates to cosmetic or dermatological
compositions containing the coal tar extract according to the
invention, preferably in a proportion of from 0.1 to 10% by
weight.
[0029] A cosmetic or dermatological composition containing 0.5% of
coal tar extract with 1 ppm of BaP has respective contents of PAH
and BaP of about 15 and 2 ppb (parts per billion).
[0030] The said compositions are proposed under the same
therapeutic indications as crude coal tar.
[0031] The examples which follow illustrate the invention without
limiting its scope.
1 Example 1: SHAMPOO PURIFIED WATER qs 100 g PULVERIZED SALICYCLIC
ACID 1.50 g UNDECYLENIC DERIVATIVE 1 to 3 g QUATERNARY POLYMER 0.5
to 1 g ETHOXYLATED SODIUM ALKYL SULFATE 9 g POLYSORBATE-20 5 to 7 g
FATTY ACID ETHANOLAMIDE PEG-6000 DISTEARATE 5 g ALKYLAMIDO BETAINE
1.5 g COCOAMPHODIACETATE 3.5 g DISODIUM EDTA 0.2 g 20 POE SORBITAN
MONOLAURATE 5 g FRAGRANCE QS DYE QS COAL TAR 0.1 .fwdarw. g 2.50
Example 2: SHAMPOO WATER qs 100 g SODIUM LAURETH SULFATE 8 g
POLYSORBATE 7 g PEG-150 DISTEARATE 4 g SODIUM UNDECYLENAMIDO
MEA-SULFOSUCCINATE 3 g SODIUM COCOAMPHODIACETATE 3 g SALICYCLIC
ACID 1.5 g FRAGRANCE 0.5 g T.E.A.-HYDROLYZED COCOYL-COLLAGEN 1 g
COAL TAR 0.1 .fwdarw. 1 g Example 3: LOTION WATER qs 100 ml
SD-ALCOHOL 39-C 63 ml FRAGRANCE 0.20 g VINYL ACETATE/CROTONIC ACID
COPOLYMER 0.15 g PEG-13 OCTANOATE 0.10 g LAURYLPYRIDINIUM CHLORIDE
0.05 g COAL TAR 0.1 .fwdarw. 1 g Example 4: CREAM WATER qs 100 g
PEG-40 SORBITAN LANOLATE 7.5 g PARAFFIN 5 g PROPYLENE GLYCOL 5 g
CETYL ALCOHOL 3 g POLYSORBATE 3 g LANOLIN 2 g SALICYCLIC ACID 1.5 g
FRAGRANCE 0.4 g COAL TAR 0.1 .fwdarw. 3 g Example 5: OIL MINERAL
OIL qs 100 g DIBUTYL ADIPATE 15 g CAPRYLIC/CAPRIC TRIGLYCERIDE 10 g
COAL TAR 0.1 .fwdarw. 2 g Example 6: SYNDET SODIUM
HEMISULFOSUCCINATE qs 100 g SODIUM ISOTHIONATE 20 g WAX OF MINERAL
ORIGIN 12 g CETYL ALCOHOL 13 g WHEAT STARCH 20 g PINE TAR 0.3 g
CADE TAR 0.3 g SALICYCLIC ACID 2 g ZINC OXIDE 5 g COAL TAR 0.1
.fwdarw. 2 g Example 7: MOUSSE DEMINERALIZED WATER qs 100 g GUAR
GUM 0.10 g JOJOBA OIL 2 g ETHYLHEXYL P-METHOXYCINNAMATE 1 g
VINYLPYRROLIDONE/DMAE METHACRYLATE 1 g PVP HEXADECENE COPOLYMER 2 g
DIMETHYL/TRIMETHYL-POLYSILOXANE 1 g CETRIMONIUM BROMIDE 0.40 g
FRAGRANCE 0.15 g COAL TAR 0.1 .fwdarw. 2 g Example 8: EMOLLIENT
SOLUTION PROPYLENE GLYCOL qs 100 g CADE TAR 10 g PINE TAR 10 g
POLYSORBATE 20 g POLYETHOXYLATED COCONUT FATTY ESTERS 10 g
POLYETHOXYLATED ALKYLPHENOL 10 g FRAGRANCE 1 g COAL TAR 0.1
.fwdarw. 5 g Example 9: GELLED BODY OIL CAPRYLIC/CAPRIC
TRIGLYCERIDE 20 .fwdarw. 30 g MINERAL OIL 36 g PETROLATUM 15 g
PEG-40 SORBITOL HEXAOLEATE 8 g QUATERNIUM-18 HECTORITE 5 g
HYDROGENATED TALLOWETH-60 MYRISTYL GLYCOL 5 g FRAGRANCE 0.5 g
BENZOIC ACID 0.3 g PROPYL GALLATE 0.02 g COAL TAR 0.1 .fwdarw. 2
g
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