Note: Descriptions are shown in the official language in which they were submitted.
WO 94/18933 ~ ~ ~ PCT/US94/02135
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SUNSCREENS CONTAINING PLANT EXTRACTS
FIELD OF THE INVENTION
The invention relates to sunscreen compositions.
More particularly, the invention relates to sunscreen
compositions that employ extracts of cereal plants
such as oats.
BACKGROUND OF THE INVENTION
Excessive exposure of human skin to either the
rays of the sun or to sun lamps which emit ultraviolet
radiation similar to natural sunlight can result in
sunburn or erythema solars as the condition is
medically defined.
In order to substantially reduce or prevent
sunburn, various sunscreen compositions have been
proposed which contain sunscreen agents which scatter
the sunlight, or which absorb the ultraviolet portion
of the sun's radiant energy, i.e., energy radiation
equivalent to about 2800 to about 4000 angstrom units.
For topical application, sunscreen compositions
must be non-toxic and non-irritating to the skin, and
capable of application to the skin as a uniform
continuous film. In addition, the active sunscreening
agents in the sunscreen compositions must be
chemically stable. In particular, the sunscreening
agents must be resistant to chemical and
photodegradation when on the skin, as well as
resistant to absorption through the skin.
3o A wide variety of sunscreen preparations are
available. Sunscreens which have both functional and
aesthetic characteristics, however, are nevertheless
sought. Typically, the sunscreen preparations of the
art have been chemically-based compositions that
employ synthetic materials such as para-aminobenzoic
WO 94/18933 _ PCT/US94/02135 ~ '
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acid (PABA) derivatives as the sunscreen agent.
Although the chemically-based sunscreen compositions
of the art have been effective in reducing sunburn,
many users suffer allergic reactions to these
products. Also, uncertainty exists over the effects
of long term exposure of the skin to chemically-based
sunscreen compositions.
A need therefore exists for sunscreen
formulations that employ a minimum of synthetic
chemical ingredients but yet provide effective
protection against ultraviolet light absorption.
SUMMARY OF THE INVENTION
Improved sunscreen compositions and their methods
of manufacture are provided. The sunscreen
compositions include extracts of cereal plants, and a
vehicle for enabling the mixture to be applied to
skin. The sunscreen compositions can further include
sunscreen blocking agents such as Ti02. The
compositions further may include dihydroxycinnamic
acid derivatives such as ferulic acid and ethyl
ferulate.
The present invention involves the discovery that
extracts of cereal plants such as oat plants
advantageously can be incorporated into sunscreen
formulations to provide sunscreen compositions. In
accordance with the invention, aqueous extracts of
cereal plants, or hydroalcoholic extracts of cereal
plants, such as aqueous ethanol cereal extracts,
aqueous methanol cereal extracts, and the like, are
employed with a vehicle to provide sunscreen
compositions. These compositions further can be
combined with well known sunscreen agents such as Ti02
to provide compositions with an SPF that is
surprisingly larger than the SPF provided by
WO 94/18933 ~ ~ ~ 6 ~ 3 ~ PCT/US94/02135
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compositions which employ only a sunscreen agent.
Useful extracts may be obtained from cereal plants
such as oats, corn, wheat, barley, rye, rice, and
mixtures thereof. Useful vehicles may include any of
water, water-based liquids, oils, gels, emulsions,
dispersions, or mixtures thereof, especially water.
The sunscreen compositions may be employed in a
variety of cosmetic formulations such as creams, gels,
powders, lotions, and the like.
to
DETAINED DESCRIPTION OF THE INVENTION
The sunscreen compositions of the invention are
produced by combining extracts of cereal plants and a
vehicle for enabling the sunscreen composition to be
applied to the skin. Useful cereal plant extracts
such as those of oats, corn, wheat, barley, rye, rice,
and mixtures thereof, especially those containing
oats, may be employed. These cereal plant extracts
may include, but are not limited to, water-soluble
extracts such as those of water, water-alcohol
mixtures, glycols, water-glycol mixtures and the like,
hydroalcoholic extracts such as water-ethanol extracts
and the like, most especially oat water-ethanol
extracts; oil extracts such as those of mineral oil,
silicones, and the like; alcohol-soluble extracts such
as those of ethanol, methanol, propanol, and the like,
especially ethanol. Sunscreen agents which may be
employed in the invention include but are not limited
to well known sunscreen agents such as aminobenzoic
acid, cinoxate, diethanolamine p-methoxycinnamate,
digalloyl trioleate, dioxybenzone, ethyl 4-
[bis(hydroxypropyl)] aminobenzoate, 2-ethylhexyl 2-
cyano-3,3-diphenylacrylate, 2-ethylhexyl p-
methoxycinnamate, 2-ethylhexyl salicylate, glyceryl
aminobenzoate, homosalate, lawsone with
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dihydroxyacetone, menthyl anthranilate, oxybenzone,
padimate A, padimate O, 2-phenylbenzimidazole-5-
sulfonic acid, red petrolatum, sulisobenzone, titanium
dioxide, triethanolamine salicylate, preferably
titanium dioxide.
In a preferred embodiment, the oat plant extract
is present in an amount of about 1.0 to 50~ by
weight, preferably from about 0.5 to 15~ by weight.
Cereal plant extracts for use in the invention
generally can be made by treating portions of cereal
plants such as oats with extraction agents by methods
known in the art to provide corresponding extracts
thereof. See F.M. Webster, Oats: Chemistry a,~
Technoloav, 1986. Useful extraction agents generally
may include water, mineral oil, hydrocarbons,
silicones, fatty acids, fatty acid derivatives, waxes,
and mixtures thereof, especially water and an
aliphatic alcohol, most preferably water and ethanol.
Hydrophobic extraction agents as well as hydrophilic
extraction agents also may be employed. Useful
hydrophobic extraction agents may include fatty acids
such as myristic acid and the~like; esters such as
isopropyl myristate and the like; diesters such as
diisopropyl adipate and the like; triesters such as
caprylic/capric triglyceride and the like;
hydrocarbons such as isododecane, petrolatum and the
like; waxes such as beeswax and the like; silicones
such as cyclomethicone, dimethicone, and derivatives
thereof such as dimethicone copolyol.
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In a preferred embodiment, the oat plant extract is
obtained by treating an oat plant with an extraction agent
selected from the group consisting of myristic acid, stearic
acid, cetyl alcohol, stearyl alcohol, isopropyl myristate,
diisopropyl adipate, caprylic/capric triglyceride,
isododecane, petrolatum, beeswax, cyclomethicone,
dimethicone, or dimethicone copolyol.
Hydrophilic extraction agents which may be
employed include water, lower molecular weight
aliphatic alcohols such as ethanol, methanol, propanol
and the like; diols such as propylene glycol, butylene
glycol and the like; polyols such as glycerine and the
like; polyol-derived materials such as polyoxyethylene
(7) glyceryl triacetate; and polymers of ethylene
oxide such as.~polyethylene glycol 200.
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Useful extraction agents also may include
volatile liquids. Such liquids are in the liquid
state at room temperature (above 22°C) and evaporate
completely from the skin within thirty minutes after
application. Volatile liquid vehicles that may be
employed as extraction agents include but are not
limited to trichlorofluoromethane, isopropanol and Coo
C,6 isoparaffins, C12-C" isoparaffins, and volatile
silicones. The amount of volatile liquid vehicles
io readily may be determined by the art skilled. Other
extraction agents will be apparent to those skilled in
the art.
Preferably in the present invention, the plant
extract is derived by washing plant material in the
form of ground or groats of cereal plants in a
solution of chloroform and methanol. The plant
material is separated from the solution. dried, and
preferably treated with a 1:1 mixture of water and ethanol to
provide a water-ethanol composition containing the
plant extract and undissolved plant material. The
water-ethanol composition containing the extract then
is separated from the plant material. The resulting
mixture is concentrated, preferably under reduced
pressure, and taken to dryness to provide a residue.
The residue is preferably washed with absolute ethanol or 99%
ethanol, and filtered to provide the plant extract.
The plant extract then is dried. The foregoing
procedure may be applied to a variety of cereal plants
such as oats, corn, wheat, barley, rye, rice, and
mixtures thereof to yield extracts. Water extracts of
oats, water-ethanol extracts of oats, and ethanol
extracts of oats, however, are preferred.
The extract of the cereal plant may be used in
the sunscreens of the invention in the form in which
it initially is derived. Alternatively, the extract
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may be concentrated to remove a portion or
substantially all of its liquid content. For example,
the extract may be concentrated under reduced pressure
via well known equipment such as a rotary evaporator,
flash evaporator, rising film evaporator, thin film
evaporator, or contherm evaporator to provide a liquid '
concentrate which can be blended with a vehicle.
Alternatively, the concentrate thoroughly can be dried
using well known equipment such as a rotary
i0 evaporator, spray dryer, or freeze dryer to yield a
' powder which can be blended with a vehicle.
The vehicle employed in the sunscreen
compositions may be any suitable material such as
gases, water, water-based liquids, lotion,
dispersion, emulsion, oil, oil-based solutions, gel or
powder mixtures thereof. The amount of vehicle in the sunscreen ,
composition readily can be determined by those skilled
in the art,_depending on composition.
In a preferred embodiment, the vehicle is selected from
water, glycols, alcohols, or mixtures thereof.
Gels useful as vehicles for the sunscreen
compositions of the invention conveniently can be
produced by mixing an oil with an organoclay. The
resulting gel may be combined with a desired amount of
the sunscreen agents and cereal plant extracts
according to the SPF desired. The specific amount of
sunscreen agent and cereal plant extract for providing
a desired SPF readily can be determined by those
skilled in the art.
Hydrophobic vehicles as well as hydrophilic
vehicles may be employed in the sunscreen compositions
of the invention. Useful hydrophobic vehicles may
include fatty acids such as myristic acid, stearic
acid and the like; fatty alcohols such as cetyl
alcohol, stearyl alcohol and the like; esters such as
isopropyl myristate; diesters such as diisopropyl
adipate; triesters such as caprylic/capric
~WO 94/18933 - 7 ~ ~ ~ ~ ~ ~ ~ PCT/US94/02135
,~ k. s.. ~ ,
triglycerides; hydrocarbons such as isododecane and
petrolatum; waxes such as beeswax; silicones such as
cyclomethicone and dimethicone, and derivatives
thereof such as dimethicone copolyol, and mixtures
thereof .
Hydrophilic vehicles which may be used in the
sunscreen compositions of the invention include water,
lower molecular weight aliphatic alcohols such as
ethanol, methanol and propanol; diols such as
propylene glycol and butylene glycol; polyols such as
glycerine; polyol-derived materials such as
polyoxyethylene(7) glyceryl triacetate; and polymers
of ethylene oxide such as polyethylene glycol 200, and
mixtures thereof.
Useful vehicles also may include volatile
liquids. Such liquids are in the liquid state at room
temperature (about 22C) and evaporate completely from
the skin within thirty minutes after application.
Volatile liquid vehicles that may be employed include
but are not limited to trichlorofluoromethane,
isopropanol and Clo C16 isoparaffins, C12 C~4
isoparaffins, and volatile silicones. The amount of
volatile liquid vehicles readily may be determined by
the art skilled.
The sunscreen compositions further may include a
preservation agent such as an anti-microbial agent to
inhibit growth, reproduction or activity of
contaminating organisms that may be present in the
composition. Other additives which may be combined
with the sunscreen compositions include moisturizers,
humectants, emollients, emulsifiers, thickeners,
stabilizers, fragrances, colorants, skin treatment
materials such as vitamin E, and the like.
As indicated, the sunscreen compositions of the
invention are made by formulating a composition
WO 94/18933 PCT/US94102135
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incorporating cereal plant extracts, optionally one or
more sunscreen agents, and a vehicle. Preferably, oat
extracts, most preferably aqueous oat extracts,
ethanol oat extracts, and aqueous oat ethanol
extracts, are employed. The oat extracts may be used
in sunscreen formulations in amounts of from 0.1 to
50% by weight, preferably 0.5 to 15%, more preferably
0.5 to 5%, most preferably 2%. The specific amounts
of sunscreen agent employed with the extract to
to achieve a desired SPF readily can.be determined by
those skilled in the art.
Dihydroxycinnamic acid derivatives such as
ferulic acid and ferulic acid esters, particularly
ethyl ferulate, may be included in the sunscreen
compositions of the invention. The dihydroxycinnamic
acid derivatives may be present in amounts of 0.05-25%
by weight, preferably 0.5 to 10%, most preferably 0.5
to 5%. Ferulic acid and ethyl ferulate may be
purchased from Aldrich Chemical Co., and ICN
Biomedicals, Inc., Cleveland, Ohio.
The sunscreen compositions conveniently may be
provided in a variety of forms, such as liquids,
creams, and sprays. Useful sprays may include any
conventional hydrocarbon propellant. The propellant
typically may be present in an amount within the range
of 5 to 15% by weight of the total composition.
Hydrocarbon propellants may include a mixture of
isobutane and propane. Other mixtures of hydrocarbon
propellants which may be employed include butane,
propane, and dimethyl ether.
The sunscreen compositions of the invention also
may be combined with cosmetic preparations, such as
skin lotions, cold creams, lipsticks, and the like
which when applied to the skin are directly exposed to '
ultraviolet ("UV") light. Methods of formulating
CA 02156930 2004-04-22
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cosmetic preparations are known. The sunscreens of
the invention, when combined with moisturizing creams,
lotions and the like, therefore, may be used to
provide protection from W light absorption as well as
to impart a soft, smooth residual feel to the skin.
The SPF of the sunscreen formulations of the
invention is evaluated by the in vivo method as
described in the Federal Register, 43(166), pp38206-
38269, Friday, August 25, 1978, Part II (full title:
Dept. of Health, Education, and Welfare, Food and Drug
Admin. - "Sunscreen Products for Over-The-Counter
Human Drugs, Proposed Safety, Effective and Labeling
Conditions").
,EXAMPLE 1
Master Batch (1) is formulated by combining the
components thereof at room temperature with a
SilversonT'"~type homogenizing mixer. Master Batch (1)
then is heated to 80°C while mixing with a Lightnin"'
propeller mixer. Master Batch (2) likewise is formed
by combining the ingredients thereof at 78°C and
mixing with a Lightnin"' propeller mixer. Master
batches (1) and (2) then are combined and mixed with a
SilversonT"'~type homogenizing mixer, mixed for 5
minutes, and cooled to 32°C to provide a first blend.
Master batch (3) is formed by mixing the components
thereof with a Lightnin"' propeller mixer at room
temperature, and the resulting mixture is added to the
first blend to provide a second blend that is cooled
to 30°C. Master batch (4), formed by mixing the
components thereof in a Lightnin'"' propeller mixer at
room temperature, then is added to the second blend.
The compositions of master batches (1)-(4) are given
in Tables 1-4, respectively.
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TABLE 1
COMPONENT PERCEI1T
Hetester PHATMl 10.00
Finsolv TNTMZ 10.00
SAT-UFTRTM Ti023 7.00
lFrom Bernel Chemical Co.
zFrom FineTex Chemical
3From U.S. Cosmetics Co.
l0
TABLE 2
COMPONENT ~ PERCENT
Deionized water 59:65
VeegumTM R4 . 0.70
' KeltrolTM FS 0.30
Methylparaben6 0.15
,From R.T. Vanderbilt Co.
6From Kelco Chemical Co.
From Nipa Chemical Co., Japan
TABLE 3
COMPONENT PERCENT
Deionized water 2.00
Ge rma l l 115TM~ 0 . 2 0
7From Sutton Laboratories
3 0 TABLE 4
COMPONENT PERCENT
Deionized Water 8.00
Water'ethanol Oat Extract 2.00
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The resulting composition is given in Table 5.
The SPF, as measured by the in vivo method, is 9Ø
TABLE 5
INGREDIENT PERCENT
Hetester PHATM 10.00
Finsolv TNTM 10.00
SAT-UFTRTM Ti02 7.00
Deionized Water 61.65
VeegumTM R 0.70
KeltrolTM F 0.30
Methylparaben 0.15
Deionized Water 8.00
Water-ethanol Oat Extract 2.00
Germall 115TM 0.20
EXAMPLE 2
The procedure of Example 1 is followed except
that SAT-UFTRTM Ti02 is not included in master batch (1)
and the amount of deionized water in master batch (2)
is increased by 7%.
EXAMPLE 3
A control example is prepared by the procedure of
Example 1 except that the water ethanol oat extract is
not included in master batch (4) and the amount of
deionized water in batch (2) is increased by 2%. The
SPF of the composition, as measured by the in vivo
method, is 5Ø
EXAMPLE 4
Following the procedure of Example 1, a
composition including ethyl ferulate in combination
with the water ethanol oat extract is prepared by
including 3% ethyl ferulate in master batch (1) and
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reducing the amount of deionized water in master batch
(2) by three percent.
EXAMPLE 5
Following the procedure of Example 2, a
composition including ethyl ferulate is provided by
including 4% ethyl ferulate in master batch (1) and
reducing the amount of deionized water in master batch
(2) by 4%.
As mentioned, the sunscreen compositions of the
io invention conveniently may be employed in cosmetic
preparations. Examples of cosmetic preparations are
provided below, where weight percents are based on the
total weight of the composition.
EXAMPLE 6
i5 A cosmetic preparation in the form of a lipstick
which employs the sunscreens of the invention is
provided. The lipstick is produced by combining the
compositions of Phase 1 and Phase 2 given below where
weight percents are based on the total weight of the
2o composition:
Phase 1 . Weiaht Percent
D&C RedTM No . 71 3 . 0
Castor oih 10.0
Phase 2
Candelilla Wax; 12.0
25 Carnauba Wax; 10.0
Beeswax; 10.0
LantrolTM~16744 20.7
CrodamolTM BS5 ~ 14.0
Castor Oilz 10.0
Propylparabenb 0.3
Ethanol Oat Extract 5.0
30 Ethyl Ferulate~ 5.0
Warner-Jenkinson Co.
2CasChem
;Frank B. Ross
~Henkel Corp.
SCroda Surfactants Ltd
6Nipa Chemical Co., Japan
35 ~Aldrich Chemical Co.
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Phase 1 ingredients are ground on a Ross three
roller mill until smooth. The resulting material is
combined with phase 2 ingredients using a Lightning'
stirrer, heated to 80°C, poured into a mold, and
cooled to room temperature.
EXAMPLE 7
A cosmetic formulation in the form of a eye
treatment gel employing the sunscreens of the
l0 invention is provided. The eye treatment gel is
produced by combining Phases 1,2, and 3 given below:
Phasq, 1 Weiaht Percent
.CarbopolTM 9401 1.25
Deionized water 61.95
Methylparaben2 0.30
Triethanolamine4 1.00
Phase 2
LubragelTM MS3 30.00
Phase 3
Aqueous oat extract 0.50
Deionized water 5.00
B.F. Goodrich
ZNipa Chemical Co., Japan
3Guardian Chemical Co.
4BASF Co.
Phase 1 is prepared by combining the components
thereof with a Lightnin"' mixer, and heating to 70°C.
The resulting mixture is cooled to 50°C, at which time
Phase 2 is added and the resulting composition is
mixed with a Lightnin'"' mixer. This composition is
further cooled to 30°C at which time Phase 3 is added,
and the resulting mixture is mixed with the Lightning'
mixer and cooled to room temperature.
EXAMPLE 8
A cosmetic formulation in the form of a sun
protection cream that employs the sunscreens of the
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invention is provided. The sun protection cream is
produced by combining Phases 1,2, and 3 given below:
Phase 1 Weight Percent
ArlacelTM 1651 5.0
ParsolTM MCX2 5.0
RobaneTM3 16 . 25
Propylparaben4 0.15
ghase 2
Deionized Water . 51.05
TweenTM 201 0.50
VeegumTM Regulars 1.75
Methylparaben4 0.30
Phase 3
Water Ethanol Oat Extract 5.0
Deionized water 15.0
ICI Americas Inc.
ZGivaudan Corp.
'Robeco Chemicals Inc.
4Nipa Chemical Co., Japan .
SR.T. Vanderbilt Co., Inc. ~
Phase 1 ingredients are combined with a Lightnin'"
Z0
mixer while heated to 78°C. Phase 2 ingredients are
combined with a Lightning' mixer while heated to 75°C.
Phases 1 and 2 are combined with a Lightnin"' mixer,
and cooled to 30°C to provide a blend. Phase 3 then
is combined with the blend with the Lightnin"' mixer.
EXAMPLE 9
A cosmetic formulation in the form of a
moisturizing cream that employs the sunscreens of the
invention is provided. The moisturizing cream is
produced by combining the compositions of Phases 1-3
.
given below:
Phase 1 Weiaht Percent
PromulgenTM Dl 3.00
Petrolatum2 5.00
Stearic Acid3 4.00
TriventTM OC-16~ 23.00
Propylparabens 0.15
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Phase 2
Deionized Water 53.40
CarbopolTM 9346 0.40
Methylparabens 0.30
Triethanolamine~ 0.75
Phase 3
Water Ethanol Oat Extract 1.50
Deionized Water 8.50
Amerchol Corp.
~Penreco
3Henkel Corp.
lo~ sTrivent Chemical Company Inc.
Nipa Chemical Co. Japan
6B.F. Goodrich Co.
'BASF Corp.
Phase 1 ingredients are combined with a Lightning"
mixer while heated to 72°C. Phase 2 ingredients are
combined with a Lightnin''~ mixer while heated to 72°C.
Phases 1 and 2 are combined with a Lightnin"" mixer and
cooled to 30°C to provide a blend. Phase 3 then is
added to the blend and further mixed with a Lightning'
Zo mixer and cooled to.room temperature to produce the
sun protection, cream.
Other useful cosmetic compositions which may be
prepared and which incorporate the sunscreen agents of
this invention include skin cleansers, tonics,
moisturizers, sun care preparations, shampoos, hair
conditioners, hair sprays, lip treatment preparations,
color cosmetics, eye area treatment preparations,
mascaras and nail treatment preparations.
While the present invention has been set forth in
terms.of specific embodiments thereof, it will be
understood that numerous variations are now enabled to
those skilled in the art. Accordingly, the invention
is to be broadly construed and limited only by the
scope of the appended claims.
